導(dao)語：如何才(cai)能寫好一篇變壓(ya)器的(de)繼電(dian)保護，這(zhe)就(jiu)需要搜集整理更多的(de)資料和文(wen)獻(xian)，歡(huan)迎閱讀(du)由公務(wu)員之家整理的(de)十(shi)篇范文(wen)，供你借鑒。

篇1

關鍵詞 電力變壓器；二次回(hui)路；瓦(wa)斯保(bao)護；定時(shi)限過(guo)電流

中圖分類號：TM4 文(wen)獻標識(shi)碼：A 文(wen)章(zhang)編號：1671—7597（2013）021-085-02

電力變壓器是電力系統變配電的重要設備，它的故障對配電的穩定、可靠和系統的正常運行都有明顯且比較嚴重的影響，同時，電力變壓器也是非常昂貴的設備，由此，提供對電力變壓器的繼電保護尤(you)為重要(yao)。變(bian)壓器(qi)通常需要(yao)的保(bao)(bao)護(hu)裝置有瓦斯(si)保(bao)(bao)護(hu)、縱差動保(bao)(bao)護(hu)或電流(liu)速斷保(bao)(bao)護(hu)、相(xiang)間短(duan)路的后備保(bao)(bao)護(hu)、接地保(bao)(bao)護(hu)、過負(fu)荷保(bao)(bao)護(hu)、過勵磁(ci)保(bao)(bao)護(hu)等等。下面就電力變(bian)壓器(qi)常用的典(dian)型保(bao)(bao)護(hu)做分析(xi)。

對于(yu)輸電(dian)線路高壓側為(wei)(wei)110 kV及(ji)(ji)以上(shang)的(de)工廠(chang)總(zong)降壓的(de)主(zhu)變壓器(qi)來說(shuo)，應(ying)裝設過(guo)(guo)流(liu)(liu)(liu)保(bao)(bao)(bao)(bao)護(hu)(hu)、速(su)斷(duan)(duan)保(bao)(bao)(bao)(bao)護(hu)(hu)和瓦斯(si)保(bao)(bao)(bao)(bao)護(hu)(hu)。過(guo)(guo)流(liu)(liu)(liu)保(bao)(bao)(bao)(bao)護(hu)(hu)作(zuo)為(wei)(wei)電(dian)流(liu)(liu)(liu)速(su)斷(duan)(duan)保(bao)(bao)(bao)(bao)護(hu)(hu)的(de)后備保(bao)(bao)(bao)(bao)護(hu)(hu)，在(zai)(zai)有可(ke)能超過(guo)(guo)電(dian)力(li)負荷(he)時，也需(xu)裝設過(guo)(guo)負荷(he)裝置(zhi)(zhi)。但(dan)是如(ru)果單(dan)臺運行的(de)電(dian)力(li)變壓器(qi)容量在(zai)(zai)10000千(qian)伏(fu)安及(ji)(ji)以上(shang)和并列運行的(de)電(dian)力(li)變壓器(qi)每臺容量在(zai)(zai)6300千(qian)伏(fu)安及(ji)(ji)以上(shang)時，則(ze)要求裝設縱聯差動(dong)(dong)裝置(zhi)(zhi)保(bao)(bao)(bao)(bao)護(hu)(hu)來取代電(dian)流(liu)(liu)(liu)速(su)斷(duan)(duan)保(bao)(bao)(bao)(bao)護(hu)(hu)。由于(yu)主(zhu)電(dian)源出口(kou)處繼電(dian)保(bao)(bao)(bao)(bao)護(hu)(hu)裝置(zhi)(zhi)動(dong)(dong)作(zuo)時限為(wei)(wei) 2 s，則(ze)變壓器(qi)保(bao)(bao)(bao)(bao)護(hu)(hu)的(de)過(guo)(guo)電(dian)流(liu)(liu)(liu)保(bao)(bao)(bao)(bao)護(hu)(hu)動(dong)(dong)作(zuo)時限可(ke)整定為(wei)(wei)1.5 s。

1 裝設瓦斯保護

當(dang)變壓(ya)器油箱內故(gu)障(zhang)產(chan)(chan)生輕微瓦斯(si)或(huo)油面(mian)下降時(shi)，瞬時(shi)動作于信號；當(dang)產(chan)(chan)生大量瓦斯(si)時(shi)，應(ying)動作于高(gao)壓(ya)側斷路器。

2 裝設定時限過電流(liu)保護

2.3.2 過負荷保護動作時(shi)限

上(shang)述(shu)設(she)計(ji)的電(dian)流及電(dian)壓回路、保護操(cao)作回路的繼(ji)電(dian)保護回路圖設(she)計(ji)情(qing)況如(ru)下：

1）電流(liu)回路：A相第一(yi)個(ge)繞組(zu)(zu)頭端與尾端編號1A1，1A2，如果是第二個(ge)繞組(zu)(zu)則用2A1，2A2，其他同理。

2）電(dian)壓(ya)(ya)回路(lu)：母線電(dian)壓(ya)(ya)回路(lu)的(de)星形接線采用單相二次額定電(dian)壓(ya)(ya)57V的(de)繞組，變電(dian)站高壓(ya)(ya)側母線電(dian)壓(ya)(ya)接線，如圖2。

①為了(le)(le)保證PT二次回路在莫端發(fa)生短路時也能迅速將故障切除，采用(yong)了(le)(le)快速動作自動開關ZK替代保險(xian)。

②采用(yong)了PT刀閘輔(fu)助接(jie)點(dian)G來切換電壓(ya)(ya)。當PT停用(yong)時G打(da)開(kai)，自動斷開(kai)電壓(ya)(ya)回路，防(fang)止(zhi)(zhi)PT停用(yong)時由二次(ci)側向一次(ci)側反饋電壓(ya)(ya)造成人身和設備事故，N600不(bu)經(jing)過ZK和G切換，是為了N600有永久接(jie)地點(dian)，防(fang)止(zhi)(zhi)PT運行時因為ZK或(huo)者G接(jie)觸不(bu)良，PT二次(ci)側失(shi)去(qu)接(jie)地點(dian)。

③1JB是擊(ji)穿保(bao)險，擊(ji)穿保(bao)險實際上是一個放(fang)(fang)電(dian)間(jian)隙，正常時(shi)不放(fang)(fang)電(dian)，當加在其上的電(dian)壓(ya)(ya)超過一定數值(zhi)后，放(fang)(fang)電(dian)間(jian)隙被擊(ji)穿而接(jie)地(di)(di)，起到保(bao)護(hu)接(jie)地(di)(di)的作用(yong)，這樣萬一中性點接(jie)地(di)(di)不良(liang)，高(gao)電(dian)壓(ya)(ya)侵(qin)入二次回(hui)路也有保(bao)護(hu)接(jie)地(di)(di)點。

④傳統回路中(zhong)，為了防止在三(san)相(xiang)斷線(xian)時斷線(xian)閉鎖裝(zhuang)置(zhi)因為無電(dian)(dian)源拒(ju)絕動作(zuo)，必須在其中(zhong)一相(xiang)上并聯一個電(dian)(dian)容器C，在三(san)相(xiang)斷線(xian)時候電(dian)(dian)容器放(fang)電(dian)(dian)，供(gong)給斷線(xian)裝(zhuang)置(zhi)一個不對稱的電(dian)(dian)源。

⑤因(yin)母(mu)(mu)線PT是接在同一母(mu)(mu)線上所有元(yuan)件(jian)公用(yong)的，為(wei)了減(jian)少電纜(lan)聯(lian)系(xi)，設計了電壓(ya)小母(mu)(mu)線1YMa，1YMb，1YMc，YMN（前面數值(zhi)“1”代表I母(mu)(mu)PT。）PT的中性點接地JD選在主控制室小母(mu)(mu)線引入處。

⑥PT二次(ci)電壓(ya)回路并不是(shi)(shi)直(zhi)接由刀閘輔助接點(dian)G來切換，而是(shi)(shi)由G去啟(qi)動(dong)一個中(zhong)間(jian)繼(ji)電器(qi)，通過(guo)這個中(zhong)間(jian)繼(ji)電器(qi)的常開接點(dian)來同時切換三(san)相電壓(ya)，該中(zhong)間(jian)繼(ji)電器(qi)起重動(dong)作用，裝設在(zai)主(zhu)控制室的輔助繼(ji)電器(qi)屏上。

3）保(bao)護操作回路(lu)：

繼電(dian)保(bao)護操(cao)作(zuo)(zuo)回(hui)路(lu)(lu)(lu)是二次回(hui)路(lu)(lu)(lu)的(de)(de)(de)基本回(hui)路(lu)(lu)(lu)，110 kV操(cao)作(zuo)(zuo)回(hui)路(lu)(lu)(lu)構成該回(hui)路(lu)(lu)(lu)的(de)(de)(de)主要部(bu)分(fen)，220 kV操(cao)作(zuo)(zuo)電(dian)壓回(hui)路(lu)(lu)(lu)也(ye)是應用(yong)同樣(yang)的(de)(de)(de)原(yuan)理設計(ji)形成的(de)(de)(de)，傳統(tong)電(dian)氣保(bao)護的(de)(de)(de)閥值、開關量進行邏輯計(ji)算(suan)后，提交給操(cao)作(zuo)(zuo)回(hui)路(lu)(lu)(lu)。對微機裝置(zhi)進行保(bao)護。因(yin)此微機裝置(zhi)保(bao)護僅僅是將傳統(tong)的(de)(de)(de)操(cao)作(zuo)(zuo)回(hui)路(lu)(lu)(lu)小型化，板塊化。下面的(de)(de)(de)操(cao)作(zuo)(zuo)回(hui)路(lu)(lu)(lu)見圖3。

1）當開(kai)(kai)關(guan)閉合(he)時(shi)(shi)，DL1立即斷開(kai)(kai)，然后DL2閉合(he)。HD、HWJ、TBJI繞組、TQ組成回路，點亮HD，HWJ開(kai)(kai)始操(cao)作，但是由于線圈(quan)的(de)各個繞組有較大的(de)電(dian)阻(zu)阻(zu)值，致(zhi)使TQ上(shang)獲得的(de)電(dian)壓(ya)不至于讓其執行跳開(kai)(kai)動(dong)作，保護跳閘出口時(shi)(shi)，TJ、TYJ、TBJI線圈(quan)、TQ直接連通，TQ上(shang)線圈(quan)電(dian)流變大，獲得較大電(dian)壓(ya)后開(kai)(kai)始工作，由于TBJI接點動(dong)作自(zi)保持，所以TBJI繞組線圈(quan)一直等待所有斷路器斷開(kai)(kai)后，TBJI才返(fan)回（即DL2斷開(kai)(kai)）。

2）二次(ci)保護合閘回路原理(li)與二次(ci)保護跳閘回路相(xiang)同。

3）在(zai)二次回路合(he)(he)閘(zha)繞(rao)組(zu)線(xian)(xian)(xian)圈上并聯了(le)TBJV回路，這個保護回路是為了(le)防(fang)(fang)止在(zai)線(xian)(xian)(xian)圈失(shi)去電(dian)壓(ya)跳閘(zha)過程中(zhong)又有(you)電(dian)壓(ya)合(he)(he)閘(zha)命(ming)令，由于短時(shi)間(jian)內的(de)繁復跳合(he)(he)閘(zha)而損壞(huai)機(ji)構。例如合(he)(he)閘(zha)后(hou)繞(rao)組(zu)充(chong)放(fang)電(dian)的(de)延遲效應，及容(rong)易(yi)造成合(he)(he)閘(zha)接點(dian)HJ或者KK的(de)5，8粘連，當開(kai)關(guan)在(zai)跳閘(zha)過程中(zhong)，使(shi)得(de)TBJI閉合(he)(he)，HJ、TBJV繞(rao)組(zu)、TBJI接通，TBJV動作時(shi)TBJV繞(rao)組(zu)線(xian)(xian)(xian)圈自(zi)保持(chi)，相當于將合(he)(he)閘(zha)線(xian)(xian)(xian)圈短路了(le)（同時(shi)TBJV閉觸點(dian)斷開(kai)，合(he)(he)閘(zha)繞(rao)組(zu)線(xian)(xian)(xian)圈被屏蔽）。這個回路叫防(fang)(fang)躍(yue)回路，防(fang)(fang)止開(kai)關(guan)跳躍(yue)的(de)意思，簡稱防(fang)(fang)躍(yue)。

4）D1、D2兩(liang)個二極管的(de)單(dan)相連通讓(rang)KKJ合(he)閘(zha)后的(de)繼電器(qi)開始工(gong)作(zuo)，KKJ的(de)工(gong)作(zuo)通過手動(dong)合(he)閘(zha)來(lai)完成，手動(dong)跳閘(zha)的(de)目(mu)的(de)是讓(rang)KKJ復(fu)歸(gui)，KKJ是電磁保持繼電器(qi)，動(dong)作(zuo)后并不是自動(dong)返回(hui)(hui)的(de)，所以KKJ又稱手動(dong)合(he)閘(zha)繼電器(qi)，廣(guang)泛(fan)用(yong)于“備自投”、“重合(he)閘(zha)”，“不對應”等(deng)的(de)二次回(hui)(hui)路(lu)設計。

5）HYJ與TYJ是(shi)感壓(ya)型的(de)跳(tiao)合(he)閘壓(ya)力繼電器，它一(yi)般(ban)接(jie)(jie)入斷(duan)路(lu)器機構的(de)氣(qi)壓(ya)接(jie)(jie)點(dian)，根據SF6產生(sheng)的(de)氣(qi)體(ti)所造(zao)(zao)(zao)成的(de)氣(qi)體(ti)壓(ya)力而(er)動作，所在(zai)以SF6為絕(jue)緣介(jie)質的(de)滅(mie)弧開(kai)關量中，若氣(qi)體(ti)發(fa)生(sheng)泄露(lu)，那(nei)么當(dang)氣(qi)體(ti)壓(ya)力降到不能(neng)(neng)夠(gou)滅(mie)弧的(de)時(shi)(shi)侯，接(jie)(jie)點(dian)J1和(he)J2連通(tong)，將操作回(hui)路(lu)斷(duan)開(kai)，防止(zhi)操作發(fa)生(sheng)，造(zao)(zao)(zao)成火災隱患。在(zai)設計和(he)施工中，值得注意的(de)是(shi)當(dang)氣(qi)壓(ya)低閉(bi)鎖電氣(qi)操作時(shi)(shi)候，不能(neng)(neng)夠(gou)在(zai)現場直(zhi)接(jie)(jie)用機械方法使(shi)開(kai)關斷(duan)開(kai)，氣(qi)壓(ya)低閉(bi)鎖是(shi)因為滅(mie)弧氣(qi)壓(ya)已不能(neng)(neng)滅(mie)弧，這(zhe)個(ge)時(shi)(shi)候任何將開(kai)關斷(duan)開(kai)的(de)方法都(dou)容易(yi)造(zao)(zao)(zao)成危(wei)險，容易(yi)讓滅(mie)弧室炸裂，造(zao)(zao)(zao)成設備損毀(hui)，正確的(de)方法是(shi)先把負(fu)荷斷(duan)路(lu)器的(de)負(fu)荷去掉之后，再手動把開(kai)關跳(tiao)開(kai)，保證(zheng)電氣(qi)的(de)安全特性。

6）輔助(zhu)的(de)位置(zhi)繼電器HWJ，TWJ，主要用于顯示二(er)次回路當前開(kai)關的(de)合(he)跳閘位置(zhi)和跳合(he)閘線圈的(de)工(gong)作(zuo)狀況。例如，在運(yun)行時，只有(you)TQ完好，TWJ才動作(zuo)。

所有保護及安控裝置作用于該(gai)斷(duan)路(lu)器的(de)出口接(jie)(jie)(jie)點都必(bi)須通過該(gai)斷(duan)路(lu)器的(de)操(cao)作系統(tong)，不允(yun)許出口接(jie)(jie)(jie)點直接(jie)(jie)(jie)接(jie)(jie)(jie)入斷(duan)路(lu)器。

目(mu)前的保(bao)護裝置都已(yi)經(jing)采用微(wei)機(ji)式(shi)保(bao)護方(fang)式(shi)，但從電氣操作(zuo)的靈敏性、快速(su)性、安全性考量(liang)，機(ji)電式(shi)保(bao)護在許多電廠及變電站被廣泛(fan)的使用著。

參考文獻

[1]熊為群，陶然.繼電保護(hu)、自動裝置及二次回(hui)路第二版[J].中國電力出版社.

[2]李瑞榮.電(dian)氣二次回路(lu)識圖與(yu)常見(jian)故障處理[J].中國電(dian)力出版(ban)社.

[3]程逢科，李公(gong)靜.電(dian)氣二次回路應用入門[J].中(zhong)國電(dian)力出版社.

篇2

關鍵詞：電(dian)力(li)系統 變(bian)壓器 常(chang)見故障 繼電(dian)保護

電力(li)(li)(li)變壓器(qi)(qi)是電力(li)(li)(li)系(xi)統(tong)中輸配電的(de)主要設備，如果(guo)發生故障將會給電力(li)(li)(li)系(xi)統(tong)的(de)正(zheng)常運(yun)行及供電可靠(kao)性帶來嚴(yan)重的(de)影響(xiang)。為了(le)保證(zheng)電力(li)(li)(li)變壓器(qi)(qi)的(de)安(an)全運(yun)行，防止事故擴大，確保電力(li)(li)(li)系(xi)統(tong)安(an)全穩定的(de)運(yun)行，可根據變壓器(qi)(qi)的(de)容量(liang)、結構及故障類(lei)型裝設相(xiang)應的(de)繼(ji)電保護裝置。

1、電(dian)力變壓器常(chang)見故(gu)障及不正常(chang)運行狀態

變壓(ya)器(qi)油(you)(you)箱(xiang)內(nei)部原副邊繞(rao)組可能發生相間(jian)短(duan)路(lu)(lu)、匝間(jian)短(duan)路(lu)(lu)、中性點直接(jie)(jie)接(jie)(jie)地(di)(di)系(xi)統側(ce)繞(rao)組的(de)(de)單相接(jie)(jie)地(di)(di)短(duan)路(lu)(lu)以及(ji)原副繞(rao)組之間(jian)的(de)(de)絕(jue)緣擊(ji)穿(chuan)等故障(zhang)。油(you)(you)箱(xiang)內(nei)部故障(zhang)產生電弧(hu)，引(yin)起絕(jue)緣油(you)(you)的(de)(de)劇烈氣化，可能導致(zhi)變壓(ya)器(qi)油(you)(you)箱(xiang)的(de)(de)爆炸。油(you)(you)箱(xiang)外部套(tao)管和引(yin)出線(xian)也可能發生相間(jian)短(duan)路(lu)(lu)和接(jie)(jie)地(di)(di)短(duan)路(lu)(lu)。

2、根據(ju)情況及異常運行方式(shi)，變壓器一(yi)般需(xu)要配(pei)置(zhi)以(yi)下保護(hu)

2.1差(cha)動(dong)保護(hu)或(huo)電流速斷保護(hu)

利(li)用(yong)變壓(ya)(ya)器(qi)高、低壓(ya)(ya)側電(dian)(dian)(dian)流大(da)小和相(xiang)位，可實(shi)現差(cha)(cha)動(dong)保(bao)(bao)(bao)(bao)(bao)護(hu)。反應變壓(ya)(ya)器(qi)引出線(xian)、套管(guan)及內(nei)部短路(lu)(lu)故障的(de)(de)縱聯(lian)(lian)差(cha)(cha)動(dong)保(bao)(bao)(bao)(bao)(bao)護(hu)或電(dian)(dian)(dian)流速斷保(bao)(bao)(bao)(bao)(bao)護(hu)。保(bao)(bao)(bao)(bao)(bao)護(hu)變壓(ya)(ya)器(qi)繞組或引出線(xian)各(ge)相(xiang)的(de)(de)相(xiang)間短路(lu)(lu)、大(da)接(jie)地電(dian)(dian)(dian)流系(xi)統的(de)(de)接(jie)地短路(lu)(lu)以及繞組匝間短路(lu)(lu)，保(bao)(bao)(bao)(bao)(bao)護(hu)瞬時動(dong)作于斷開變壓(ya)(ya)器(qi)的(de)(de)各(ge)側斷路(lu)(lu)器(qi)。差(cha)(cha)動(dong)保(bao)(bao)(bao)(bao)(bao)護(hu)不僅(jin)能夠(gou)正確區(qu)(qu)分區(qu)(qu)內(nei)外故障，還可以在無(wu)(wu)其他元(yuan)件的(de)(de)保(bao)(bao)(bao)(bao)(bao)護(hu)配(pei)合的(de)(de)情況下無(wu)(wu)延時的(de)(de)切除(chu)區(qu)(qu)內(nei)各(ge)種(zhong)故障，因此差(cha)(cha)動(dong)保(bao)(bao)(bao)(bao)(bao)護(hu)經常作為電(dian)(dian)(dian)氣(qi)(qi)主設(she)(she)備(bei)的(de)(de)主保(bao)(bao)(bao)(bao)(bao)護(hu)被廣泛應用(yong)于各(ge)種(zhong)電(dian)(dian)(dian)氣(qi)(qi)主設(she)(she)備(bei)和線(xian)路(lu)(lu)的(de)(de)保(bao)(bao)(bao)(bao)(bao)護(hu)中。《繼電(dian)(dian)(dian)保(bao)(bao)(bao)(bao)(bao)護(hu)和安全自動(dong)裝(zhuang)置技術規程(cheng)》中對裝(zhuang)設(she)(she)縱聯(lian)(lian)差(cha)(cha)動(dong)保(bao)(bao)(bao)(bao)(bao)護(hu)和電(dian)(dian)(dian)流速斷保(bao)(bao)(bao)(bao)(bao)護(hu)有如下規定：

2.1.1對6.3MVA以(yi)下(xia)(xia)廠用(yong)變壓(ya)器(qi)和(he)并列運行的變壓(ya)器(qi)，以(yi)及10MVA以(yi)下(xia)(xia)廠用(yong)備用(yong)變壓(ya)器(qi)和(he)單獨運行的變壓(ya)器(qi)，當后備保(bao)護(hu)時(shi)間大于0.5s時(shi)，應裝設電流速斷保(bao)護(hu)。

2.1.2對(dui)6.3MVA及(ji)以(yi)上廠用(yong)工作變(bian)(bian)壓(ya)器(qi)(qi)和(he)并列運行(xing)的(de)(de)變(bian)(bian)壓(ya)器(qi)(qi)，10MVA及(ji)以(yi)上廠用(yong)備用(yong)變(bian)(bian)壓(ya)器(qi)(qi)和(he)單獨運行(xing)的(de)(de)變(bian)(bian)壓(ya)器(qi)(qi)，以(yi)及(ji)2MVA及(ji)以(yi)上用(yong)電(dian)流速斷(duan)保護靈敏性不符合要求(qiu)的(de)(de)變(bian)(bian)壓(ya)器(qi)(qi)，應裝設縱(zong)聯差動保護。

2.1.3對高(gao)壓側電壓為(wei)330kV及以(yi)上變(bian)壓器，可裝設(she)雙(shuang)重縱聯差動保護。

2.2過電流保護

電(dian)(dian)(dian)(dian)(dian)(dian)網中發生相(xiang)間(jian)短路(lu)(lu)故障時，電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)會突(tu)然(ran)(ran)增大(da)，電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)突(tu)然(ran)(ran)下降(jiang)，過(guo)流(liu)保(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(hu)就是(shi)按線路(lu)(lu)選擇(ze)性的(de)要(yao)求(qiu)(qiu)(qiu)，整定(ding)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)繼電(dian)(dian)(dian)(dian)(dian)(dian)器的(de)動作電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)的(de)。過(guo)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)保(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(hu)可(ke)作為瓦斯保(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(hu)和(he)差動保(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(hu)或電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)速(su)斷保(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(hu)的(de)后(hou)備(bei)保(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(hu)，反應變(bian)(bian)(bian)(bian)壓(ya)器外部相(xiang)間(jian)短路(lu)(lu)。一般過(guo)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)保(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(hu)宜(yi)用于降(jiang)壓(ya)變(bian)(bian)(bian)(bian)壓(ya)器；復合電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)起動的(de)過(guo)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)保(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(hu)，宜(yi)用于升(sheng)壓(ya)變(bian)(bian)(bian)(bian)壓(ya)器、系統(tong)聯絡變(bian)(bian)(bian)(bian)壓(ya)器和(he)過(guo)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)保(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(hu)不(bu)滿足靈敏性要(yao)求(qiu)(qiu)(qiu)的(de)降(jiang)壓(ya)變(bian)(bian)(bian)(bian)壓(ya)器；負(fu)序電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)和(he)單相(xiang)式低電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)起動過(guo)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)保(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(hu)，可(ke)用于63MVA及以(yi)上升(sheng)壓(ya)變(bian)(bian)(bian)(bian)壓(ya)器；對于升(sheng)壓(ya)變(bian)(bian)(bian)(bian)壓(ya)器、系統(tong)聯絡變(bian)(bian)(bian)(bian)壓(ya)器，當采(cai)用過(guo)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)保(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(hu)不(bu)能滿足靈敏性和(he)選擇(ze)性要(yao)求(qiu)(qiu)(qiu)時，可(ke)采(cai)用阻抗(kang)保(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(hu)。

2.3零序電流保護

反應大接(jie)地電(dian)(dian)流(liu)系統(tong)中(zhong)變壓(ya)器(qi)(qi)外部接(jie)地短路(lu)的(de)零序電(dian)(dian)流(liu)保護(hu)(hu)。110kV及以上大接(jie)地電(dian)(dian)流(liu)系統(tong)中(zhong)，如果變壓(ya)器(qi)(qi)中(zhong)性點可能接(jie)地運行，對(dui)于兩側或三側電(dian)(dian)源的(de)升(sheng)壓(ya)變壓(ya)器(qi)(qi)或降壓(ya)變壓(ya)器(qi)(qi)應裝設(she)零序電(dian)(dian)流(liu)保護(hu)(hu)，作變壓(ya)器(qi)(qi)主保護(hu)(hu)的(de)后(hou)備(bei)保護(hu)(hu)，并(bing)作為相鄰元件的(de)后(hou)備(bei)保護(hu)(hu)。

利用(yong)接(jie)(jie)地時產生的(de)零(ling)序(xu)(xu)(xu)電(dian)(dian)(dian)流(liu)(liu)(liu)使保(bao)(bao)(bao)護動作的(de)裝置(zhi)，叫(jiao)零(ling)序(xu)(xu)(xu)電(dian)(dian)(dian)流(liu)(liu)(liu)保(bao)(bao)(bao)護。在(zai)(zai)電(dian)(dian)(dian)纜線路上都采用(yong)專門的(de)零(ling)序(xu)(xu)(xu)電(dian)(dian)(dian)流(liu)(liu)(liu)互(hu)感(gan)(gan)器(qi)(qi)來實現接(jie)(jie)地保(bao)(bao)(bao)護。將零(ling)序(xu)(xu)(xu)電(dian)(dian)(dian)流(liu)(liu)(liu)互(hu)感(gan)(gan)器(qi)(qi)套地三芯(xin)電(dian)(dian)(dian)纜上，電(dian)(dian)(dian)流(liu)(liu)(liu)繼電(dian)(dian)(dian)器(qi)(qi)接(jie)(jie)在(zai)(zai)互(hu)感(gan)(gan)器(qi)(qi)的(de)二(er)次(ci)線圈(quan)上，在(zai)(zai)正常運行或無接(jie)(jie)地故(gu)障時，由(you)于電(dian)(dian)(dian)纜三相(xiang)電(dian)(dian)(dian)流(liu)(liu)(liu)的(de)向量之和等于零(ling)，零(ling)序(xu)(xu)(xu)互(hu)感(gan)(gan)器(qi)(qi)二(er)次(ci)線圈(quan)的(de)電(dian)(dian)(dian)流(liu)(liu)(liu)也為零(ling)(只有很小的(de)不(bu)平衡電(dian)(dian)(dian)流(liu)(liu)(liu)），故(gu)電(dian)(dian)(dian)流(liu)(liu)(liu)繼電(dian)(dian)(dian)器(qi)(qi)不(bu)動作。當發生接(jie)(jie)地故(gu)障時，零(ling)序(xu)(xu)(xu)互(hu)感(gan)(gan)器(qi)(qi)二(er)次(ci)線圈(quan)將出現較大的(de)電(dian)(dian)(dian)流(liu)(liu)(liu)，使電(dian)(dian)(dian)流(liu)(liu)(liu)繼電(dian)(dian)(dian)器(qi)(qi)動作，以便發出信號(hao)或切(qie)除(chu)故(gu)障。

2.4過負荷保護

反應變壓器(qi)對稱過負荷的過負荷保護，僅作(zuo)用于信(xin)號

對于(yu)400kVA及以上(shang)的(de)變(bian)壓(ya)器(qi)(qi)(qi)，當數臺并(bing)(bing)列運行(xing)或單獨運行(xing)并(bing)(bing)作為其他負(fu)(fu)荷(he)(he)的(de)備用電(dian)(dian)(dian)源時，應根據可能過(guo)(guo)負(fu)(fu)荷(he)(he)的(de)情(qing)(qing)況裝設過(guo)(guo)負(fu)(fu)荷(he)(he)保護。對自耦變(bian)壓(ya)器(qi)(qi)(qi)和多繞組變(bian)壓(ya)器(qi)(qi)(qi)，保護裝置(zhi)應能反應公共繞組及各(ge)側過(guo)(guo)負(fu)(fu)荷(he)(he)的(de)情(qing)(qing)況。變(bian)壓(ya)器(qi)(qi)(qi)的(de)過(guo)(guo)負(fu)(fu)荷(he)(he)電(dian)(dian)(dian)流，在大多數情(qing)(qing)況下，都是三(san)相對稱的(de)，故(gu)過(guo)(guo)負(fu)(fu)荷(he)(he)保護只要接入一相電(dian)(dian)(dian)流，電(dian)(dian)(dian)流繼電(dian)(dian)(dian)器(qi)(qi)(qi)來實現，并(bing)(bing)進過(guo)(guo)一定(ding)的(de)延(yan)時作用于(yu)信(xin)號。選擇保護安裝在哪(na)一側時，要考慮(lv)它能夠反映變(bian)壓(ya)器(qi)(qi)(qi)所有各(ge)側線圈過(guo)(guo)負(fu)(fu)荷(he)(he)情(qing)(qing)況。在無經常(chang)值班人(ren)員的(de)變(bian)電(dian)(dian)(dian)所，必要時過(guo)(guo)負(fu)(fu)荷(he)(he)保護可動作于(yu)跳閘(zha)或斷開部分負(fu)(fu)荷(he)(he)。

2.5過勵磁保護

目前的(de)(de)大型變壓(ya)器設(she)計中，為了節省材料(liao)，降(jiang)低造價(jia)，減少(shao)運輸重量，鐵(tie)心的(de)(de)額定工(gong)作磁(ci)通密度(du)都設(she)計得較高(gao)，接近(jin)飽(bao)和(he)磁(ci)密，因此(ci)在過(guo)電(dian)壓(ya)情況下，很容(rong)易產生(sheng)過(guo)勵(li)磁(ci)。在過(guo)勵(li)磁(ci)時，由于(yu)鐵(tie)心飽(bao)和(he)，勵(li)磁(ci)阻抗(kang)下降(jiang)，勵(li)磁(ci)電(dian)流(liu)增加的(de)(de)很快，當工(gong)作磁(ci)密達到正常磁(ci)密的(de)(de)1.3~1.4倍時，勵(li)磁(ci)電(dian)流(liu)可達到額定電(dian)流(liu)水(shui)平(ping)。其次由于(yu)勵(li)磁(ci)電(dian)流(liu)是非正弦波，含有(you)許多高(gao)次諧波分(fen)量，而鐵(tie)心和(he)其他(ta)金屬構件(jian)的(de)(de)渦流(liu)損耗與頻率的(de)(de)平(ping)方成正比(bi)，可引起鐵(tie)心、金屬構件(jian)、絕緣材料(liao)的(de)(de)嚴重過(guo)熱，若過(guo)勵(li)磁(ci)倍數較高(gao)，持(chi)續(xu)時間(jian)過(guo)長(chang)，可能使(shi)變壓(ya)器損壞。因此(ci)，高(gao)壓(ya)側為500kV的(de)(de)變壓(ya)器宜裝設(she)過(guo)勵(li)磁(ci)保護。

裝設變壓(ya)器過(guo)(guo)勵磁(ci)(ci)(ci)保護的(de)目(mu)的(de)是為(wei)了檢測(ce)變壓(ya)器的(de)過(guo)(guo)勵磁(ci)(ci)(ci)情況，及時發出(chu)信(xin)號或(huo)動作于跳閘，使變壓(ya)器的(de)過(guo)(guo)勵磁(ci)(ci)(ci)不超過(guo)(guo)允許的(de)限度，防(fang)止變壓(ya)器因過(guo)(guo)勵磁(ci)(ci)(ci)而損壞。

2.6瓦斯保護

瓦(wa)斯(si)保(bao)護是(shi)反(fan)應變壓(ya)器(qi)內部氣體的(de)(de)(de)數量和流(liu)動(dong)的(de)(de)(de)速度而動(dong)作(zuo)的(de)(de)(de)保(bao)護，保(bao)護變壓(ya)器(qi)油(you)(you)(you)箱內各種短路(lu)(lu)故障，特別是(shi)繞組的(de)(de)(de)相間(jian)短路(lu)(lu)和匝間(jian)短路(lu)(lu)。當(dang)(dang)油(you)(you)(you)箱內故障產生輕微瓦(wa)斯(si)或油(you)(you)(you)面下降(jiang)(jiang)時，應瞬時動(dong)作(zuo)于信號；當(dang)(dang)油(you)(you)(you)箱內故障嚴(yan)重時，產生的(de)(de)(de)氣體量非常大，氣體流(liu)和油(you)(you)(you)流(liu)相互(hu)夾(jia)雜著(zhu)沖向(xiang)油(you)(you)(you)枕上(shang)部，由于壓(ya)強的(de)(de)(de)作(zuo)用(yong)，繼電(dian)器(qi)內部的(de)(de)(de)油(you)(you)(you)面降(jiang)(jiang)低，瓦(wa)斯(si)保(bao)護啟動(dong)，瞬時斷(duan)開變壓(ya)器(qi)各側的(de)(de)(de)斷(duan)路(lu)(lu)器(qi)。《繼電(dian)保(bao)護和安全(quan)自動(dong)裝置技術規程》規定，0.4MVA及(ji)以上(shang)車間(jian)內油(you)(you)(you)浸(jin)式變壓(ya)器(qi)和0.8MVA及(ji)以上(shang)油(you)(you)(you)浸(jin)式變壓(ya)器(qi)，均應裝設瓦(wa)斯(si)保(bao)護。

瓦(wa)斯(si)保護(hu)具有可靠(kao)、靈敏和速動(dong)性，但只能(neng)反(fan)應(ying)油箱內部的(de)(de)故障(zhang)，不能(neng)反(fan)應(ying)引出線的(de)(de)故障(zhang)。有時還會受到一些外界因素的(de)(de)影響，所(suo)以(yi)還需要設置其他后備(bei)保護(hu)。

2.7壓力保護

壓力保護也是變壓器(qi)油(you)箱內部故障的主保護，當(dang)變壓器(qi)內部故障時(shi)，溫度(du)升高(gao)，油(you)膨脹壓力增高(gao)，彈簧帶動繼電器(qi)觸點(dian)(dian)，使觸點(dian)(dian)閉合，作用于(yu)切除(chu)變壓器(qi)。

篇3

關鍵詞：電力系統；變壓(ya)器(qi)；繼電保護(hu)裝置；油沉式(shi)變壓(ya)器(qi)；斷路器(qi)保護(hu)

電(dian)力(li)(li)變(bian)壓(ya)器的(de)正常(chang)運(yun)行可以保(bao)(bao)(bao)(bao)證(zheng)電(dian)力(li)(li)的(de)有(you)效運(yun)輸，而保(bao)(bao)(bao)(bao)證(zheng)電(dian)力(li)(li)變(bian)壓(ya)器正常(chang)發揮功能的(de)關鍵是繼電(dian)保(bao)(bao)(bao)(bao)護，其工作能否完成將影響著電(dian)力(li)(li)體系的(de)完整(zheng)度。只有(you)對(dui)電(dian)力(li)(li)變(bian)壓(ya)器的(de)繼電(dian)保(bao)(bao)(bao)(bao)護進(jin)行科學分析，才能在電(dian)力(li)(li)變(bian)壓(ya)器續電(dian)出(chu)現(xian)故障時做出(chu)合理應對(dui)，更好地處理電(dian)力(li)(li)運(yun)輸過程(cheng)中可能出(chu)現(xian)的(de)各種意外狀況(kuang)，從而保(bao)(bao)(bao)(bao)證(zheng)電(dian)力(li)(li)系統的(de)穩定性(xing)(xing)和安全性(xing)(xing)。

1 繼電保護基本(ben)概念(nian)

在研究(jiu)電(dian)力(li)系統故障和危及(ji)安全運行的異常工(gong)況時，需要探討應對事故的自動化措(cuo)施。由于這些(xie)措(cuo)施主要用帶(dai)有觸(chu)點(dian)(dian)或輔(fu)助觸(chu)點(dian)(dian)的繼(ji)電(dian)器來(lai)保護電(dian)力(li)系統及(ji)其(qi)元件，例如線(xian)路、發電(dian)機、變(bian)壓器和母線(xian)等，使之免遭損(sun)害，所(suo)以稱其(qi)為(wei)繼(ji)電(dian)保護。

2 電力變(bian)壓器的繼電保(bao)護

GB/T50062―2008《電力(li)裝置的(de)(de)繼電保(bao)護和自動裝置設(she)計規范(fan)》中第4.0.3條，針對變(bian)壓器(qi)引出(chu)線、套管及(ji)內(nei)部短路故(gu)障的(de)(de)保(bao)護范(fan)圍已經(jing)有了詳(xiang)細的(de)(de)說明，結(jie)合《工業與民用配電設(she)計手冊》第三(san)版(ban)第七(qi)章的(de)(de)內(nei)容(rong)，電力(li)變(bian)壓器(qi)的(de)(de)繼電保(bao)護配置（容(rong)量在5000kV?A以下(xia)的(de)(de)電力(li)變(bian)壓器(qi)）如下(xia)表所示。

通過上表不難看出，除容量小于400kV?A的(de)(de)變壓器(qi)外，目前大多數的(de)(de)設(she)計(ji)中(zhong)，高壓側均采用斷路器(qi)，變壓器(qi)均需(xu)要裝(zhuang)設(she)帶時(shi)限的(de)(de)過電(dian)流(liu)(liu)保(bao)護，并(bing)且當過電(dian)流(liu)(liu)保(bao)護時(shi)限大于0.5s時(shi)，還(huan)需(xu)要加(jia)裝(zhuang)電(dian)流(liu)(liu)速斷保(bao)護；對于2000～5000kV?A的(de)(de)變壓器(qi)，當電(dian)流(liu)(liu)速斷保(bao)護不能(neng)滿足靈敏(min)性時(shi)，還(huan)需(xu)要裝(zhuang)設(she)縱聯差(cha)動(dong)保(bao)護。

3 電力(li)變(bian)壓器繼電保(bao)護實例

某大型(xing)(xing)研發(fa)中心項目，兩(liang)路10kV高壓(ya)(ya)(ya)進線(xian)(xian)(xian)，高壓(ya)(ya)(ya)母(mu)(mu)線(xian)(xian)(xian)采(cai)用(yong)單(dan)母(mu)(mu)線(xian)(xian)(xian)分段運行方式(shi)，高壓(ya)(ya)(ya)開關柜采(cai)用(yong)斷(duan)路器保護；選用(yong)兩(liang)臺10/0.4kV的油沉(chen)式(shi)變(bian)壓(ya)(ya)(ya)器，容(rong)量(liang)為1250kV?A，變(bian)壓(ya)(ya)(ya)器型(xing)(xing)號為SCB11-10/0.4kV-1250//Dyn11。低壓(ya)(ya)(ya)側母(mu)(mu)線(xian)(xian)(xian)采(cai)用(yong)單(dan)母(mu)(mu)線(xian)(xian)(xian)分段運行方式(shi)。10kV母(mu)(mu)線(xian)(xian)(xian)上短路容(rong)量(liang)假定(ding)為300MV?A。

本案例中，過電(dian)流繼(ji)電(dian)器(qi)(qi)選用GL感應型，是(shi)(shi)考慮到(dao)GL型繼(ji)電(dian)器(qi)(qi)的反時(shi)(shi)(shi)(shi)限(xian)特性。反時(shi)(shi)(shi)(shi)限(xian)過電(dian)流繼(ji)電(dian)器(qi)(qi)的動(dong)作(zuo)根據(ju)電(dian)流的大(da)小決定，電(dian)流上升(sheng)越快動(dong)作(zuo)時(shi)(shi)(shi)(shi)間(jian)越短，上升(sheng)慢時(shi)(shi)(shi)(shi)間(jian)就長(chang)。而DL定時(shi)(shi)(shi)(shi)限(xian)過電(dian)流繼(ji)電(dian)器(qi)(qi)是(shi)(shi)根據(ju)電(dian)流的大(da)小變化(hua)，在大(da)于整定值時(shi)(shi)(shi)(shi)發出(chu)信(xin)號，通過時(shi)(shi)(shi)(shi)間(jian)繼(ji)電(dian)器(qi)(qi)延(yan)時(shi)(shi)(shi)(shi)，到(dao)時(shi)(shi)(shi)(shi)間(jian)就發出(chu)跳閘信(xin)號。所以(yi)對短路這種情況來說用GL型是(shi)(shi)最理想的，可以(yi)做到(dao)瞬(shun)時(shi)(shi)(shi)(shi)保(bao)護，而DL型一定要在時(shi)(shi)(shi)(shi)間(jian)繼(ji)電(dian)器(qi)(qi)延(yan)時(shi)(shi)(shi)(shi)時(shi)(shi)(shi)(shi)間(jian)到(dao)才能動(dong)作(zuo)。

3.1 過(guo)電流(liu)保護

根(gen)據短路電(dian)流(liu)的(de)(de)計算方法（或查《工業與民用配電(dian)設計手冊》第(di)三版P.169）不(bu)難得(de)出：在(zai)變壓(ya)器低(di)壓(ya)側(ce)發生三相短路時，變壓(ya)器出口(kou)端的(de)(de)三相短路電(dian)流(liu)為Ik=25.22kA，流(liu)過高(gao)壓(ya)側(ce)的(de)(de)超瞬態電(dian)流(liu)為：

（1）

正(zheng)常(chang)運行時(shi)，變壓器的額定電流（高壓側）為

（2）

因此，裝(zhuang)設三個(ge)GL型(xing)過電(dian)流(liu)(liu)繼電(dian)器和三個(ge)電(dian)流(liu)(liu)比為100/5的電(dian)流(liu)(liu)互感器TA1～TA3，即

nTA=100/5 （3）

繼電(dian)器接線方式如圖(tu)2所示，采用(yong)接于相(xiang)電(dian)流的方式。

根據《工業與民(min)用(yong)配電(dian)設計(ji)手冊》第(di)三(san)版第(di)7章(zhang)表7-3可以查出，過電(dian)流(liu)保護時，保護裝置的(de)動(dong)作電(dian)流(liu)按(an)下式(shi)計(ji)算（應躲過可能出現的(de)過負荷電(dian)流(liu)）

（4）

式中，Krel為(wei)可靠系(xi)數，取1.3；Kjx為(wei)接線系(xi)數，取1；Kgh為(wei)過(guo)負(fu)荷系(xi)數，取3；Kr為(wei)繼(ji)電器返回系(xi)數，取0.85。

將(jiang)以上(shang)數(shu)值(zhi)及式（2）、式（3）代入式（4），得(de)保護裝置(zhi)的動(dong)作(zuo)電流Iop.K=16.52A，取17A。

繼續校驗保護裝置(zhi)的靈敏系數，應(ying)滿足（按電(dian)(dian)力系統最小(xiao)運行方式下(xia)，低壓(ya)側兩相短路時流過高壓(ya)側的短路電(dian)(dian)流校驗）

（5）

為(wei)省略計(ji)算，依然假(jia)定電(dian)力系統最小運(yun)行方式下，10kV母線(xian)上短路容(rong)量(liang)為(wei)300MV?A（實際應(ying)(ying)用時應(ying)(ying)從電(dian)力部門獲(huo)取相關數(shu)據），即

（6）

則(ze)最小(xiao)運行(xing)方式下(xia)變壓(ya)器低壓(ya)側兩相短路時，流(liu)過高(gao)壓(ya)側的穩態電流(liu)

（7）

式(shi)中，2/ 為(wei)變(bian)壓器低壓側發生(sheng)兩相短路時，流過(guo)高壓側的電流分布系(xi)數，其取值根據變(bian)壓器連接組(zu)別、繼電器接線(xian)方式(shi)、短路故障形式(shi)以及(ji)保護方式(shi)的不(bu)同(tong)略(lve)有不(bu)同(tong)。

3.2 電(dian)流速(su)斷(duan)保護

同理，假定電(dian)力系統最(zui)大運行(xing)方(fang)式下，變(bian)壓(ya)器低壓(ya)側三(san)相短路時，流過高壓(ya)側的超瞬態電(dian)流為 （8）

則保護裝置的(de)動作(zuo)電流（應躲過(guo)低(di)壓側短路時，流過(guo)保護裝置的(de)最大短路電流）為 （9）

式中，Krel為(wei)可靠系數，取1.5；Kjx為(wei)接線(xian)系數，取1。

將式(shi)(shi)（3）、式(shi)(shi)（8）代入式(shi)(shi)（9），得

（10）

取76A。瞬(shun)動電流倍(bei)數為76A/17A=4.47，取5倍(bei)。

3.3 低(di)壓側單(dan)相接(jie)地故障保護

擬(ni)利用高壓(ya)(ya)側三(san)相式過電(dian)流(liu)保(bao)(bao)(bao)護(hu)完成低壓(ya)(ya)側的(de)單相接地保(bao)(bao)(bao)護(hu)，保(bao)(bao)(bao)護(hu)裝置的(de)過電(dian)流(liu)和動作時限與過電(dian)流(liu)保(bao)(bao)(bao)護(hu)相同(tong)，校(xiao)驗保(bao)(bao)(bao)護(hu)裝置的(de)靈敏性。則保(bao)(bao)(bao)護(hu)裝置的(de)靈敏系數(shu)為(wei)（11）

最小運行方式(shi)下，變壓(ya)器低壓(ya)側母(mu)線(xian)或母(mu)干線(xian)末端單(dan)相接地(di)短(duan)路時，流過高壓(ya)側的(de)穩態電流為I2k1.min。

4 結束語

總之，電(dian)(dian)(dian)(dian)(dian)力(li)(li)變(bian)(bian)壓(ya)(ya)器(qi)(qi)是現代電(dian)(dian)(dian)(dian)(dian)力(li)(li)系(xi)統(tong)的(de)(de)(de)重要組成(cheng)部分，如果它出現故障(zhang)，將會極大(da)的(de)(de)(de)影響(xiang)電(dian)(dian)(dian)(dian)(dian)力(li)(li)系(xi)統(tong)的(de)(de)(de)正(zheng)(zheng)常(chang)運轉。而(er)電(dian)(dian)(dian)(dian)(dian)力(li)(li)變(bian)(bian)壓(ya)(ya)器(qi)(qi)的(de)(de)(de)繼(ji)(ji)電(dian)(dian)(dian)(dian)(dian)保(bao)護是電(dian)(dian)(dian)(dian)(dian)力(li)(li)變(bian)(bian)壓(ya)(ya)器(qi)(qi)最重要的(de)(de)(de)保(bao)護體系(xi)和(he)設備，同(tong)時也是保(bao)護電(dian)(dian)(dian)(dian)(dian)力(li)(li)變(bian)(bian)壓(ya)(ya)器(qi)(qi)的(de)(de)(de)有效手段(duan)，不僅可以保(bao)證(zheng)電(dian)(dian)(dian)(dian)(dian)力(li)(li)變(bian)(bian)壓(ya)(ya)器(qi)(qi)的(de)(de)(de)正(zheng)(zheng)常(chang)運行，而(er)且還(huan)可以將發(fa)生故障(zhang)的(de)(de)(de)可能性(xing)降到最低。因(yin)此，為了能夠發(fa)揮電(dian)(dian)(dian)(dian)(dian)力(li)(li)變(bian)(bian)壓(ya)(ya)器(qi)(qi)繼(ji)(ji)電(dian)(dian)(dian)(dian)(dian)保(bao)護工(gong)(gong)作的(de)(de)(de)最大(da)價(jia)值，必須對(dui)電(dian)(dian)(dian)(dian)(dian)力(li)(li)變(bian)(bian)壓(ya)(ya)器(qi)(qi)的(de)(de)(de)繼(ji)(ji)電(dian)(dian)(dian)(dian)(dian)保(bao)護技術進(jin)行分析，從而(er)保(bao)障(zhang)電(dian)(dian)(dian)(dian)(dian)力(li)(li)變(bian)(bian)壓(ya)(ya)器(qi)(qi)繼(ji)(ji)電(dian)(dian)(dian)(dian)(dian)保(bao)護工(gong)(gong)作的(de)(de)(de)正(zheng)(zheng)常(chang)進(jin)行，保(bao)證(zheng)電(dian)(dian)(dian)(dian)(dian)力(li)(li)系(xi)統(tong)的(de)(de)(de)安全(quan)性(xing)和(he)穩定性(xing)，減少電(dian)(dian)(dian)(dian)(dian)力(li)(li)系(xi)統(tong)故障(zhang)發(fa)生的(de)(de)(de)概率。

參考文獻

篇4

Abstract:The short circuit impedance of 35kV high-capacity transformers is relatively small, resulting in over-current protection 35kV and 35kV lines 10 kV side of transformer backup protection could not coordinate with each other, through the example of substation protection setting calculations, the problems are analyzed by the definite value cases of transformer relay protection calculation. The methods of add 10 kV side of the outlet sections with a sensitivity of back-up to 35kV transformer are proposed which could solve the problems of non-coordination and could improve reliability.

關(guan)鍵詞:大容量(liang)變(bian)壓器;繼電保護;后備保護;整(zheng)定;配合(he)

Key words:high capacity transformer; relay protection; back up protection; coordination

中圖分類號:TM77 文獻標(biao)識碼:A文章編(bian)號:1006-4311(2010)03-0063-01

0引言

針對35kV大(da)容量變壓器的相關繼電保(bao)護(hu)整定計算進行分析(xi),并提(ti)出在35kV變壓器10kV側增加一段后備保(bao)護(hu)的方法(fa),可(ke)實現10kV母線或(huo)10kV線路(lu)故障時動作的選擇性,提(ti)高(gao)了用戶變電站的供電可(ke)靠性。

1保護的整定計算

計算(suan)以一條(tiao)110kV變(bian)電(dian)(dian)站的35kV線路所連(lian)接變(bian)電(dian)(dian)站的20MVA變(bian)壓(ya)器為例。已知(zhi)35kV線路長度為4km,35kV變(bian)壓(ya)器型號為SFZ11-20MVA,阻(zu)抗電(dian)(dian)壓(ya)為8%,變(bian)35kV系統母線阻(zu)抗為0.28/0.36。按(an)照DL/T584-2007《110kV電(dian)(dian)網繼電(dian)(dian)保護裝(zhuang)置運行整定規(gui)(gui)程》(以下簡稱《整定規(gui)(gui)程》),延時(shi)電(dian)(dian)流(liu)(liu)速斷(duan)定值應對本(ben)線路末(mo)端故障有足夠(gou)的靈敏度,DZ≤10min/KLM;KLM為靈敏系數,KLM≥1.5;IDmin為本(ben)線路末(mo)端兩相短路最小電(dian)(dian)流(liu)(liu)。

為保(bao)(bao)(bao)(bao)(bao)(bao)(bao)證(zheng)選擇性(xing),35kV線路(lu)(lu)延時(shi)(shi)(shi)(shi)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)速斷保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)應躲(duo)過(guo)(guo)35kV變(bian)(bian)(bian)(bian)(bian)(bian)電(dian)(dian)(dian)(dian)(dian)站(zhan)10kV母(mu)(mu)線短路(lu)(lu),即應滿足(zu)(zu),IDmax為35kV變(bian)(bian)(bian)(bian)(bian)(bian)電(dian)(dian)(dian)(dian)(dian)站(zhan)10kV母(mu)(mu)線短路(lu)(lu)時(shi)(shi)(shi)(shi)流(liu)(liu)(liu)過(guo)(guo)35kV線路(lu)(lu)三(san)相(xiang)(xiang)短路(lu)(lu)最(zui)(zui)(zui)大(da)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu);對(dui)于35kV中(zhong)、小容量變(bian)(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)其35kV供(gong)(gong)電(dian)(dian)(dian)(dian)(dian)線路(lu)(lu)延時(shi)(shi)(shi)(shi)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)速斷保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)定(ding)(ding)(ding)值(zhi)一(yi)般能(neng)同時(shi)(shi)(shi)(shi)滿足(zu)(zu)要(yao)求,這樣的(de)(de)定(ding)(ding)(ding)值(zhi)既可(ke)(ke)對(dui)全(quan)線路(lu)(lu)故障有足(zu)(zu)夠(gou)靈敏度,又能(neng)可(ke)(ke)靠躲(duo)過(guo)(guo)對(dui)側(ce)(ce)10kV母(mu)(mu)線故障。變(bian)(bian)(bian)(bian)(bian)(bian)35kV母(mu)(mu)線兩(liang)相(xiang)(xiang)短路(lu)(lu)最(zui)(zui)(zui)小電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)為:IDmin=23(0.3165+600.12)=2702A;變(bian)(bian)(bian)(bian)(bian)(bian)10kV母(mu)(mu)線短路(lu)(lu)流(liu)(liu)(liu)過(guo)(guo)35kV線路(lu)(lu)的(de)(de)三(san)相(xiang)(xiang)短路(lu)(lu)最(zui)(zui)(zui)大(da)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)為:IDmax=(0.28+10.51620+0.375)=2012A;很(hen)顯然(ran),同時(shi)(shi)(shi)(shi)滿足(zu)(zu)以(yi)上兩(liang)式(shi)的(de)(de)定(ding)(ding)(ding)值(zhi)是不存(cun)在(zai)的(de)(de)。從以(yi)上計(ji)算不難(nan)看(kan)出(chu),正是由于大(da)容量變(bian)(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)的(de)(de)投入(ru),使變(bian)(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)的(de)(de)阻抗值(zhi)變(bian)(bian)(bian)(bian)(bian)(bian)小,35kV變(bian)(bian)(bian)(bian)(bian)(bian)電(dian)(dian)(dian)(dian)(dian)站(zhan)10kV母(mu)(mu)線短路(lu)(lu)時(shi)(shi)(shi)(shi)流(liu)(liu)(liu)過(guo)(guo)35kV線路(lu)(lu)短路(lu)(lu)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)較大(da),是造成保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)不配(pei)合的(de)(de)重要(yao)原(yuan)因。因此,35kV主(zhu)變(bian)(bian)(bian)(bian)(bian)(bian)后備保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)按照GB/T14285-2006《繼電(dian)(dian)(dian)(dian)(dian)保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)和安全(quan)自動裝置技(ji)術規(gui)(gui)程》第4.3.5.1條及《整定(ding)(ding)(ding)規(gui)(gui)程》第6.2.9條的(de)(de)規(gui)(gui)定(ding)(ding)(ding),供(gong)(gong)電(dian)(dian)(dian)(dian)(dian)區35kV主(zhu)變(bian)(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)后備保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)整定(ding)(ding)(ding)計(ji)算的(de)(de)一(yi)般原(yuan)則為:①高(gao)、低(di)(di)壓(ya)(ya)側(ce)(ce)均(jun)采用過(guo)(guo)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu):②過(guo)(guo)流(liu)(liu)(liu)保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)定(ding)(ding)(ding)值(zhi)按躲(duo)過(guo)(guo)最(zui)(zui)(zui)大(da)負荷電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)整定(ding)(ding)(ding);③對(dui)用戶變(bian)(bian)(bian)(bian)(bian)(bian)電(dian)(dian)(dian)(dian)(dian)站(zhan)一(yi)臺主(zhu)變(bian)(bian)(bian)(bian)(bian)(bian)運行一(yi)臺備用(或單臺主(zhu)變(bian)(bian)(bian)(bian)(bian)(bian))的(de)(de)運行方式(shi),高(gao)、低(di)(di)壓(ya)(ya)側(ce)(ce)過(guo)(guo)流(liu)(liu)(liu)保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)均(jun)采用以(yi)較短時(shi)(shi)(shi)(shi)限跳(tiao)(tiao)低(di)(di)壓(ya)(ya)側(ce)(ce)分段,以(yi)較長時(shi)(shi)(shi)(shi)限跳(tiao)(tiao)變(bian)(bian)(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)兩(liang)側(ce)(ce)開關,跳(tiao)(tiao)兩(liang)側(ce)(ce)開關時(shi)(shi)(shi)(shi)間(jian)(jian)與35kV線路(lu)(lu)過(guo)(guo)流(liu)(liu)(liu)保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)動作(zuo)時(shi)(shi)(shi)(shi)間(jian)(jian)采用相(xiang)(xiang)同。根據以(yi)上原(yuan)則,對(dui)35kV變(bian)(bian)(bian)(bian)(bian)(bian)主(zhu)變(bian)(bian)(bian)(bian)(bian)(bian)高(gao)、低(di)(di)壓(ya)(ya)側(ce)(ce)后備保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)整定(ding)(ding)(ding)如下:高(gao)壓(ya)(ya)側(ce)(ce)后備保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)KKI=0.95×330=451A;低(di)(di)壓(ya)(ya)側(ce)(ce)后備保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu):DZkPH.maxPHf中(zhong):kPH為配(pei)合系(xi)數,低(di)(di)壓(ya)(ya)側(ce)(ce)后備保(bao)(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)動作(zuo)時(shi)(shi)(shi)(shi)限及跳(tiao)(tiao)閘(zha)開關與高(gao)壓(ya)(ya)側(ce)(ce)相(xiang)(xiang)同。

2 保護整定計算(suan)中存在的問題

保(bao)(bao)(bao)護(hu)整(zheng)定計(ji)算中存(cun)在(zai)(zai)的(de)(de)(de)問(wen)題。根據《整(zheng)定規(gui)程》規(gui)定,35kV線(xian)路(lu)(lu)(lu)延(yan)時(shi)電(dian)(dian)流(liu)(liu)速斷(duan)保(bao)(bao)(bao)護(hu)必(bi)須保(bao)(bao)(bao)證靈敏度(du)要求,即(ji)(ji)定值(zhi)必(bi)須進(jin)行計(ji)算取值(zhi),這樣35kV線(xian)路(lu)(lu)(lu)延(yan)時(shi)電(dian)(dian)流(liu)(liu)速斷(duan)保(bao)(bao)(bao)護(hu)的(de)(de)(de)保(bao)(bao)(bao)護(hu)范(fan)圍延(yan)伸至10kV母線(xian)。為保(bao)(bao)(bao)證電(dian)(dian)網故(gu)障時(shi)有選擇性(xing)地保(bao)(bao)(bao)護(hu)動作,根據《整(zheng)定規(gui)程》4.3.4條(tiao)規(gui)定,35kV線(xian)路(lu)(lu)(lu)延(yan)時(shi)電(dian)(dian)流(liu)(liu)速斷(duan)保(bao)(bao)(bao)護(hu)可按(an)與10kV出線(xian)靈敏度(du)段(duan)的(de)(de)(de)電(dian)(dian)流(liu)(liu)保(bao)(bao)(bao)護(hu)進(jin)行配(pei)合,按(an)10kV線(xian)路(lu)(lu)(lu)靈敏度(du)段(duan)的(de)(de)(de)保(bao)(bao)(bao)護(hu)時(shi)限(xian)(xian)為0.3s考慮(lv),35kV線(xian)路(lu)(lu)(lu)限(xian)(xian)時(shi)電(dian)(dian)流(liu)(liu)速斷(duan)保(bao)(bao)(bao)護(hu)可按(an)延(yan)長一個時(shi)限(xian)(xian)級(ji)差即(ji)(ji)0.6s考慮(lv)。此時(shi),在(zai)(zai)35kV變電(dian)(dian)站10kV母線(xian)發生(sheng)短路(lu)(lu)(lu)故(gu)障時(shi),如(ru)發生(sheng)短路(lu)(lu)(lu),此時(shi)在(zai)(zai)變壓(ya)器后(hou)(hou)備(bei)保(bao)(bao)(bao)護(hu)動作前(1.1s跳(tiao)10kV分段(duan)后(hou)(hou)恢復10kV另一段(duan)母線(xian)正常(chang)供電(dian)(dian)),35kV線(xian)路(lu)(lu)(lu)延(yan)時(shi)電(dian)(dian)流(liu)(liu)速斷(duan)保(bao)(bao)(bao)護(hu)(0.6s)可能(neng)已經(jing)先(xian)動作跳(tiao)開35kV線(xian)路(lu)(lu)(lu),在(zai)(zai)經(jing)過不少(shao)于1.0s延(yan)時(shi)重合閘(zha)動作后(hou)(hou)將再次重合于永(yong)久性(xing)故(gu)障而(er)跳(tiao)閘(zha)。同樣,所在(zai)(zai)母線(xian)10kV線(xian)路(lu)(lu)(lu)故(gu)障,10kV開關(guan)拒動時(shi),同樣會發生(sheng)上述越級(ji)跳(tiao)閘(zha)現象。這種在(zai)(zai)35kV大(da)容量變壓(ya)器系統中按(an)常(chang)規(gui)的(de)(de)(de)整(zheng)定配(pei)合方法(fa)在(zai)(zai)故(gu)障時(shi)擴(kuo)大(da)了(le)停電(dian)(dian)范(fan)圍(多停了(le)一段(duan)10kV母線(xian)),而(er)且(qie)可能(neng)使變壓(ya)器后(hou)(hou)備(bei)保(bao)(bao)(bao)護(hu)因時(shi)限(xian)(xian)較長在(zai)(zai)母線(xian)故(gu)障時(shi)沒有動作機(ji)會。

3 解決不配合問題的措施

為(wei)解決所(suo)(suo)出現(xian)的(de)(de)不配(pei)(pei)合問(wen)題,可以考慮在(zai)(zai)現(xian)有(you)接線(xian)(xian)(xian)(xian)方式的(de)(de)情況下(xia),探(tan)索(suo)新的(de)(de)整(zheng)(zheng)定配(pei)(pei)合方案,以滿足保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)配(pei)(pei)合關(guan)(guan)系(xi),提高供電(dian)(dian)(dian)(dian)(dian)的(de)(de)可靠性。(1)35kV線(xian)(xian)(xian)(xian)路(lu)(lu)限時(shi)(shi)(shi)電(dian)(dian)(dian)(dian)(dian)流(liu)速(su)斷(duan)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)按保(bao)(bao)(bao)(bao)(bao)(bao)證線(xian)(xian)(xian)(xian)路(lu)(lu)末(mo)(mo)端故(gu)障(zhang)(zhang)靈(ling)(ling)(ling)敏(min)度(du)整(zheng)(zheng)定,并考慮和(he)10kV線(xian)(xian)(xian)(xian)路(lu)(lu)有(you)靈(ling)(ling)(ling)敏(min)度(du)段(duan)電(dian)(dian)(dian)(dian)(dian)流(liu)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(0.3s)配(pei)(pei)合,保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)時(shi)(shi)(shi)限按比(bi)10kV線(xian)(xian)(xian)(xian)路(lu)(lu)電(dian)(dian)(dian)(dian)(dian)流(liu)有(you)靈(ling)(ling)(ling)敏(min)度(du)段(duan)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)長一個(ge)時(shi)(shi)(shi)限段(duan)(0.6s)整(zheng)(zheng)定,10kV線(xian)(xian)(xian)(xian)路(lu)(lu)有(you)靈(ling)(ling)(ling)敏(min)度(du)段(duan)電(dian)(dian)(dian)(dian)(dian)流(liu)定值(zhi);ID Z.10≤103.55IDZ.35/KPH中:IDZ.10為(wei)10kV線(xian)(xian)(xian)(xian)路(lu)(lu)有(you)靈(ling)(ling)(ling)敏(min)度(du)段(duan)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)電(dian)(dian)(dian)(dian)(dian)流(liu)定值(zhi);IDZ.35為(wei)35kV線(xian)(xian)(xian)(xian)路(lu)(lu)延時(shi)(shi)(shi)電(dian)(dian)(dian)(dian)(dian)流(liu)速(su)斷(duan)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)電(dian)(dian)(dian)(dian)(dian)流(liu)定值(zhi);kPH為(wei)配(pei)(pei)合系(xi)數,kPH≥1.1。(2)考慮在(zai)(zai)35kV變壓(ya)(ya)器10kV側后(hou)備(bei)(bei)(bei)(bei)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)中增加(jia)(jia)一段(duan)過流(liu)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu),保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)電(dian)(dian)(dian)(dian)(dian)流(liu)定值(zhi)按10kV母(mu)(mu)(mu)線(xian)(xian)(xian)(xian)故(gu)障(zhang)(zhang)又不低于1.5倍的(de)(de)靈(ling)(ling)(ling)敏(min)度(du)整(zheng)(zheng)定,動作時(shi)(shi)(shi)限按與10kV線(xian)(xian)(xian)(xian)路(lu)(lu)有(you)靈(ling)(ling)(ling)敏(min)度(du)段(duan)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)的(de)(de)一個(ge)時(shi)(shi)(shi)限整(zheng)(zheng)定。10kV母(mu)(mu)(mu)線(xian)(xian)(xian)(xian)短路(lu)(lu)流(liu)過主(zhu)(zhu)變低壓(ya)(ya)側開關(guan)(guan)的(de)(de)兩相短路(lu)(lu)最(zui)小(xiao)電(dian)(dian)(dian)(dian)(dian)流(liu)為(wei):ID.min=23(0.36+05.51020+0.375)=5570A,DZ(2)D.minLM5570I≤IK=1.5=3713A動作時(shi)(shi)(shi)限:與10kV線(xian)(xian)(xian)(xian)路(lu)(lu)有(you)靈(ling)(ling)(ling)敏(min)度(du)段(duan)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)配(pei)(pei)合,0.6s跳10kV母(mu)(mu)(mu)線(xian)(xian)(xian)(xian)分(fen)段(duan)開關(guan)(guan),0.9s跳主(zhu)(zhu)變10kV側開關(guan)(guan)。主(zhu)(zhu)變10kV側增加(jia)(jia)一段(duan)后(hou)備(bei)(bei)(bei)(bei)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu),當(dang)所(suo)(suo)在(zai)(zai)母(mu)(mu)(mu)線(xian)(xian)(xian)(xian)及(ji)其所(suo)(suo)連設(she)備(bei)(bei)(bei)(bei)發(fa)生故(gu)障(zhang)(zhang)時(shi)(shi)(shi)或本(ben)段(duan)母(mu)(mu)(mu)線(xian)(xian)(xian)(xian)上10kV線(xian)(xian)(xian)(xian)路(lu)(lu)故(gu)障(zhang)(zhang)開關(guan)(guan)拒動時(shi)(shi)(shi),后(hou)備(bei)(bei)(bei)(bei)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)0.6s跳開10kV母(mu)(mu)(mu)線(xian)(xian)(xian)(xian)分(fen)段(duan)開關(guan)(guan)切(qie)除故(gu)障(zhang)(zhang)點,同(tong)時(shi)(shi)(shi)35kV線(xian)(xian)(xian)(xian)路(lu)(lu)延時(shi)(shi)(shi)電(dian)(dian)(dian)(dian)(dian)流(liu)速(su)斷(duan)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)動作后(hou)重合成功(gong),恢復對(dui)10kV另一段(duan)母(mu)(mu)(mu)線(xian)(xian)(xian)(xian)供電(dian)(dian)(dian)(dian)(dian)。這(zhe)樣可以很好(hao)地(di)解決10kV母(mu)(mu)(mu)線(xian)(xian)(xian)(xian)及(ji)其連接設(she)備(bei)(bei)(bei)(bei)故(gu)障(zhang)(zhang)及(ji)10kV線(xian)(xian)(xian)(xian)路(lu)(lu)故(gu)障(zhang)(zhang)開關(guan)(guan)拒動時(shi)(shi)(shi)的(de)(de)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)配(pei)(pei)合問(wen)題,保(bao)(bao)(bao)(bao)(bao)(bao)留原(yuan)后(hou)備(bei)(bei)(bei)(bei)保(bao)(bao)(bao)(bao)(bao)(bao)護(hu)(hu)(hu)(hu)(hu)(電(dian)(dian)(dian)(dian)(dian)流(liu)定值(zhi)較(jiao)小(xiao)),可對(dui)10kV線(xian)(xian)(xian)(xian)路(lu)(lu)末(mo)(mo)端故(gu)障(zhang)(zhang)起后(hou)備(bei)(bei)(bei)(bei)作用。

4結語

對(dui)(dui)于35kV大容(rong)量變壓(ya)器由(you)于阻抗(kang)較小造成(cheng)的(de)保護(hu)不能相互配合問(wen)題,本文(wen)通過分析計算,提出(chu)了(le)采用(yong)35kV主(zhu)變壓(ya)器10kV側(ce)增(zeng)加一段后備(bei)(bei)保護(hu)的(de)方法,可有效解決10kV母線(xian)及(ji)其連接設(she)備(bei)(bei)故(gu)障和10kV線(xian)路(lu)故(gu)障開關(guan)拒動時的(de)保護(hu)配合問(wen)題,防(fang)止出(chu)現越級跳閘擴大事(shi)故(gu)停電(dian)范圍,保留(liu)原后備(bei)(bei)保護(hu),可對(dui)(dui)10kV線(xian)路(lu)末端故(gu)障起到(dao)很好(hao)的(de)后備(bei)(bei)作用(yong),保護(hu)方案做到(dao)了(le)較好(hao)配合,提高了(le)供電(dian)可靠性(xing)。

參考文獻:

篇5

關鍵詞：繼電(dian)保護；供電(dian)系(xi)統；電(dian)力(li)變壓器故障(zhang)

中圖分類號：TM7文獻標識碼： A

一、電力變壓器的常見故障和非正常運行狀態

電力變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)的(de)故(gu)(gu)障(zhang)(zhang)分為內(nei)部(bu)和(he)(he)外(wai)(wai)部(bu)兩種(zhong)故(gu)(gu)障(zhang)(zhang)。內(nei)部(bu)故(gu)(gu)障(zhang)(zhang)指變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)油箱里面發生(sheng)的(de)各種(zhong)故(gu)(gu)障(zhang)(zhang)，主要(yao)(yao)(yao)靠瓦(wa)斯和(he)(he)差動(dong)(dong)(dong)保(bao)(bao)(bao)護(hu)(hu)動(dong)(dong)(dong)作切除(chu)變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)；外(wai)(wai)部(bu)故(gu)(gu)障(zhang)(zhang)指油箱外(wai)(wai)部(bu)絕緣套管及其引出(chu)(chu)線(xian)(xian)上發生(sheng)的(de)各種(zhong)故(gu)(gu)障(zhang)(zhang)，一般(ban)情況下(xia)由差動(dong)(dong)(dong)保(bao)(bao)(bao)護(hu)(hu)動(dong)(dong)(dong)作切除(chu)變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)。速(su)動(dong)(dong)(dong)保(bao)(bao)(bao)護(hu)(hu)（瓦(wa)斯和(he)(he)差動(dong)(dong)(dong)）無延時(shi)動(dong)(dong)(dong)作切除(chu)故(gu)(gu)障(zhang)(zhang)變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)，設備(bei)是否(fou)(fou)損壞(huai)(huai)主要(yao)(yao)(yao)取決于變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)的(de)動(dong)(dong)(dong)穩定(ding)性。而在變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)各側母線(xian)(xian)及其相連間(jian)(jian)隔的(de)引出(chu)(chu)設備(bei)故(gu)(gu)障(zhang)(zhang)時(shi)，若故(gu)(gu)障(zhang)(zhang)設備(bei)未配保(bao)(bao)(bao)護(hu)(hu)（如低壓(ya)(ya)側母線(xian)(xian)保(bao)(bao)(bao)護(hu)(hu)）或保(bao)(bao)(bao)護(hu)(hu)拒動(dong)(dong)(dong)時(shi)，則只能靠變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)后(hou)備(bei)保(bao)(bao)(bao)護(hu)(hu)動(dong)(dong)(dong)作跳開相應(ying)開關使變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)脫(tuo)離故(gu)(gu)障(zhang)(zhang)。因后(hou)備(bei)保(bao)(bao)(bao)護(hu)(hu)帶延時(shi)動(dong)(dong)(dong)作，所以變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)必(bi)(bi)然要(yao)(yao)(yao)承受一定(ding)時(shi)間(jian)(jian)段(duan)內(nei)的(de)區(qu)外(wai)(wai)故(gu)(gu)障(zhang)(zhang)造成的(de)過電流，在此時(shi)間(jian)(jian)段(duan)內(nei)變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)是否(fou)(fou)損壞(huai)(huai)主要(yao)(yao)(yao)取決于變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)的(de)熱穩定(ding)性。因此，變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)后(hou)備(bei)保(bao)(bao)(bao)護(hu)(hu)的(de)定(ding)值整(zheng)定(ding)與(yu)變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)自身的(de)熱穩定(ding)要(yao)(yao)(yao)求(qiu)之間(jian)(jian)存(cun)在著必(bi)(bi)然的(de)聯系(xi)。

變(bian)壓(ya)器的(de)(de)(de)(de)(de)(de)不正常運行(xing)狀態(tai)(tai)即變(bian)壓(ya)器在(zai)故(gu)障狀態(tai)(tai)運行(xing)的(de)(de)(de)(de)(de)(de)狀態(tai)(tai)，變(bian)壓(ya)器在(zai)不正常的(de)(de)(de)(de)(de)(de)運行(xing)狀態(tai)(tai)運行(xing)，會加快(kuai)絕緣(yuan)材料老化(hua)、使(shi)得鐵芯、繞(rao)組(zu)和其他(ta)金(jin)屬構件熱(re)量過高，從而降低絕緣(yuan)強度，減(jian)少變(bian)壓(ya)器的(de)(de)(de)(de)(de)(de)使(shi)用壽命，導致其他(ta)故(gu)障的(de)(de)(de)(de)(de)(de)發(fa)生(sheng)。因此(ci)，電(dian)力(li)變(bian)壓(ya)器要(yao)裝設繼電(dian)保(bao)護(hu)裝置(zhi)，以及(ji)時(shi)將短(duan)路(lu)故(gu)障切斷，防止更(geng)大的(de)(de)(de)(de)(de)(de)損(sun)壞的(de)(de)(de)(de)(de)(de)發(fa)生(sheng)。

二(er)、電力變壓(ya)器常見(jian)故(gu)障(zhang)

電(dian)力(li)變壓(ya)(ya)(ya)(ya)(ya)器(qi)在(zai)運(yun)行(xing)過程中，一般(ban)常(chang)(chang)出現(xian)(xian)的(de)(de)(de)(de)(de)(de)(de)故(gu)(gu)障(zhang)(zhang)主(zhu)要(yao)(yao)(yao)(yao)分為(wei)內(nei)部(bu)(bu)故(gu)(gu)障(zhang)(zhang)和外部(bu)(bu)故(gu)(gu)障(zhang)(zhang)兩種。內(nei)部(bu)(bu)故(gu)(gu)障(zhang)(zhang)的(de)(de)(de)(de)(de)(de)(de)危(wei)險(xian)性(xing)要(yao)(yao)(yao)(yao)大(da)于外部(bu)(bu)故(gu)(gu)障(zhang)(zhang)，曾(ceng)有內(nei)部(bu)(bu)故(gu)(gu)障(zhang)(zhang)在(zai)嚴(yan)重情(qing)(qing)況(kuang)下導(dao)致(zhi)(zhi)變壓(ya)(ya)(ya)(ya)(ya)器(qi)油箱爆炸，造(zao)成(cheng)(cheng)整個供電(dian)系統癱瘓(huan)。電(dian)力(li)變壓(ya)(ya)(ya)(ya)(ya)器(qi)常(chang)(chang)見的(de)(de)(de)(de)(de)(de)(de)故(gu)(gu)障(zhang)(zhang)主(zhu)要(yao)(yao)(yao)(yao)分為(wei)芯體(ti)(ti)、變壓(ya)(ya)(ya)(ya)(ya)器(qi)油、磁(ci)(ci)路(lu)等方(fang)面(mian)的(de)(de)(de)(de)(de)(de)(de)故(gu)(gu)障(zhang)(zhang)。芯體(ti)(ti)故(gu)(gu)障(zhang)(zhang)主(zhu)要(yao)(yao)(yao)(yao)就(jiu)是(shi)集中在(zai)絕(jue)緣層(ceng)老化或(huo)(huo)者線圈受(shou)潮導(dao)致(zhi)(zhi)的(de)(de)(de)(de)(de)(de)(de)短(duan)路(lu)方(fang)面(mian)，短(duan)路(lu)會使繞組造(zao)成(cheng)(cheng)的(de)(de)(de)(de)(de)(de)(de)機械損傷，影(ying)響變壓(ya)(ya)(ya)(ya)(ya)器(qi)的(de)(de)(de)(de)(de)(de)(de)使用。變壓(ya)(ya)(ya)(ya)(ya)器(qi)油故(gu)(gu)障(zhang)(zhang)主(zhu)要(yao)(yao)(yao)(yao)是(shi)絕(jue)緣油長(chang)時(shi)間的(de)(de)(de)(de)(de)(de)(de)高溫運(yun)行(xing)，導(dao)致(zhi)(zhi)氧化或(huo)(huo)吸(xi)收空氣中的(de)(de)(de)(de)(de)(de)(de)水分使絕(jue)緣性(xing)能(neng)下降，進而導(dao)致(zhi)(zhi)一定(ding)的(de)(de)(de)(de)(de)(de)(de)閃絡(luo)放電(dian)情(qing)(qing)況(kuang)。也有部(bu)(bu)分的(de)(de)(de)(de)(de)(de)(de)變壓(ya)(ya)(ya)(ya)(ya)器(qi)油故(gu)(gu)障(zhang)(zhang)是(shi)由于油泥(ni)沉積(ji)阻塞油道，進而使變壓(ya)(ya)(ya)(ya)(ya)器(qi)的(de)(de)(de)(de)(de)(de)(de)散熱性(xing)能(neng)變差(cha)，長(chang)時(shi)間運(yun)行(xing)導(dao)致(zhi)(zhi)危(wei)險(xian)發(fa)生。磁(ci)(ci)路(lu)故(gu)(gu)障(zhang)(zhang)是(shi)變壓(ya)(ya)(ya)(ya)(ya)器(qi)最常(chang)(chang)見故(gu)(gu)障(zhang)(zhang)，磁(ci)(ci)路(lu)的(de)(de)(de)(de)(de)(de)(de)芯體(ti)(ti)絕(jue)緣老化，導(dao)致(zhi)(zhi)漏磁(ci)(ci)漏電(dian)情(qing)(qing)況(kuang)，或(huo)(huo)磁(ci)(ci)路(lu)的(de)(de)(de)(de)(de)(de)(de)螺絲碰(peng)接鐵(tie)芯導(dao)致(zhi)(zhi)磁(ci)(ci)路(lu)不能(neng)正常(chang)(chang)工作(zuo)，或(huo)(huo)壓(ya)(ya)(ya)(ya)(ya)鐵(tie)松動引起(qi)電(dian)磁(ci)(ci)鐵(tie)振動和噪聲等。這些(xie)故(gu)(gu)障(zhang)(zhang)有的(de)(de)(de)(de)(de)(de)(de)能(neng)夠通過異常(chang)(chang)現(xian)(xian)象發(fa)現(xian)(xian)并(bing)及時(shi)排除，但更多(duo)的(de)(de)(de)(de)(de)(de)(de)是(shi)隱(yin)形故(gu)(gu)障(zhang)(zhang)，平時(shi)很(hen)難發(fa)現(xian)(xian)，使在(zai)變壓(ya)(ya)(ya)(ya)(ya)器(qi)故(gu)(gu)障(zhang)(zhang)狀(zhuang)態運(yun)行(xing)是(shi)很(hen)危(wei)險(xian)的(de)(de)(de)(de)(de)(de)(de)，需要(yao)(yao)(yao)(yao)及時(shi)的(de)(de)(de)(de)(de)(de)(de)發(fa)現(xian)(xian)并(bing)且排除故(gu)(gu)障(zhang)(zhang)。

三、繼電保護

（一）繼電保(bao)護的特(te)點與要求

繼電保護裝(zhuang)置是目前人(ren)們采用(yong)的(de)最普遍(bian)的(de)裝(zhuang)置，自繼電保護裝(zhuang)置應用(yong)開始，短時間內就得到(dao)廣泛利用(yong)，主要是由其特(te)點決定的(de)。繼電保護的(de)特(te)點是可(ke)靠性高、

實用(yong)(yong)性(xing)強(qiang)，并且(qie)能夠實現(xian)(xian)(xian)遠程監控(kong)。繼電(dian)(dian)(dian)保護(hu)(hu)應用(yong)(yong)的(de)(de)(de)裝(zhuang)置(zhi)是配置(zhi)合理(li)并且(qie)科(ke)學技(ji)術(shu)(shu)含(han)量高的(de)(de)(de)繼電(dian)(dian)(dian)保護(hu)(hu)裝(zhuang)置(zhi)。繼電(dian)(dian)(dian)保護(hu)(hu)的(de)(de)(de)信(xin)息(xi)(xi)管(guan)理(li)技(ji)術(shu)(shu)采用(yong)(yong)方(fang)法庫與(yu)數據庫，整個(ge)(ge)信(xin)息(xi)(xi)管(guan)理(li)系統(tong)(tong)由傳統(tong)(tong)的(de)(de)(de)分(fen)散(san)式傳輸轉(zhuan)變(bian)為集中式運輸。各種新技(ji)術(shu)(shu)與(yu)新系統(tong)(tong)的(de)(de)(de)使(shi)用(yong)(yong)使(shi)繼電(dian)(dian)(dian)保護(hu)(hu)的(de)(de)(de)可(ke)靠(kao)性(xing)增強(qiang)。繼電(dian)(dian)(dian)保護(hu)(hu)信(xin)息(xi)(xi)系統(tong)(tong)的(de)(de)(de)應用(yong)(yong)，使(shi)供(gong)電(dian)(dian)(dian)系統(tong)(tong)中出現(xian)(xian)(xian)的(de)(de)(de)實際問(wen)題，能夠通(tong)過(guo)系統(tong)(tong)有效的(de)(de)(de)對(dui)各個(ge)(ge)部分(fen)中的(de)(de)(de)各類(lei)數據及時(shi)使(shi)用(yong)(yong)和共(gong)享，更方(fang)便工作(zuo)人員的(de)(de)(de)操(cao)作(zuo)，因此繼電(dian)(dian)(dian)保護(hu)(hu)的(de)(de)(de)實用(yong)(yong)性(xing)也得(de)到增強(qiang)。隨著電(dian)(dian)(dian)子技(ji)術(shu)(shu)與(yu)信(xin)息(xi)(xi)化(hua)技(ji)術(shu)(shu)在各個(ge)(ge)領(ling)域的(de)(de)(de)推廣(guang)與(yu)應用(yong)(yong)，供(gong)電(dian)(dian)(dian)系統(tong)(tong)也及時(shi)的(de)(de)(de)根據實際情況采用(yong)(yong)了新的(de)(de)(de)信(xin)息(xi)(xi)化(hua)技(ji)術(shu)(shu)。通(tong)過(guo)電(dian)(dian)(dian)子信(xin)息(xi)(xi)技(ji)術(shu)(shu)的(de)(de)(de)應用(yong)(yong)，能夠對(dui)供(gong)電(dian)(dian)(dian)系統(tong)(tong)的(de)(de)(de)電(dian)(dian)(dian)力(li)變(bian)壓(ya)器的(de)(de)(de)運行狀(zhuang)態，進行二十四小時(shi)無人監控(kong)。最先進的(de)(de)(de)是通(tong)過(guo)運行狀(zhuang)態分(fen)析，能夠發現(xian)(xian)(xian)電(dian)(dian)(dian)力(li)變(bian)壓(ya)器的(de)(de)(de)隱形(xing)故(gu)(gu)(gu)障，及時(shi)的(de)(de)(de)在大的(de)(de)(de)故(gu)(gu)(gu)障產生前(qian)把(ba)隱形(xing)故(gu)(gu)(gu)障排(pai)除(chu)，保障了供(gong)電(dian)(dian)(dian)系統(tong)(tong)的(de)(de)(de)安(an)全平穩(wen)運行，減少了經濟損失。

現代的(de)(de)繼(ji)(ji)電(dian)(dian)保(bao)(bao)護(hu)(hu)雖然(ran)有(you)著非(fei)常好的(de)(de)優勢，但(dan)是對(dui)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)的(de)(de)要(yao)求(qiu)(qiu)更(geng)高，沒有(you)好的(de)(de)繼(ji)(ji)電(dian)(dian)保(bao)(bao)護(hu)(hu)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)，繼(ji)(ji)電(dian)(dian)保(bao)(bao)護(hu)(hu)的(de)(de)特點與(yu)(yu)性能就不能完全(quan)發揮。繼(ji)(ji)電(dian)(dian)保(bao)(bao)護(hu)(hu)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)最基本的(de)(de)要(yao)求(qiu)(qiu)就是靈敏性與(yu)(yu)可靠(kao)(kao)性。供電(dian)(dian)系(xi)統(tong)(tong)一般(ban)要(yao)求(qiu)(qiu)繼(ji)(ji)電(dian)(dian)保(bao)(bao)護(hu)(hu)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)的(de)(de)設計原理、整定計算、安裝(zhuang)(zhuang)(zhuang)調(diao)試等全(quan)部要(yao)正(zheng)確(que)無(wu)誤，還要(yao)求(qiu)(qiu)組(zu)成(cheng)繼(ji)(ji)電(dian)(dian)保(bao)(bao)護(hu)(hu)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)的(de)(de)各元件(jian)的(de)(de)質(zhi)量(liang)可靠(kao)(kao)。繼(ji)(ji)電(dian)(dian)保(bao)(bao)護(hu)(hu)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)也需(xu)要(yao)定期的(de)(de)進行運行維護(hu)(hu)檢查與(yu)(yu)保(bao)(bao)養，盡量(liang)提高供電(dian)(dian)系(xi)統(tong)(tong)變壓器繼(ji)(ji)電(dian)(dian)保(bao)(bao)護(hu)(hu)的(de)(de)可靠(kao)(kao)性。

（二）繼電保護措施

1.瓦斯保護

瓦(wa)斯(si)保(bao)護(hu)是供電(dian)(dian)系(xi)(xi)統(tong)(tong)電(dian)(dian)力(li)(li)變(bian)(bian)(bian)(bian)(bian)壓(ya)器(qi)油(you)(you)(you)箱(xiang)的(de)主要保(bao)護(hu)措(cuo)施，能(neng)(neng)(neng)夠在變(bian)(bian)(bian)(bian)(bian)壓(ya)器(qi)油(you)(you)(you)箱(xiang)發生內部(bu)故障(zhang)的(de)時候自(zi)動(dong)啟動(dong)。變(bian)(bian)(bian)(bian)(bian)壓(ya)器(qi)油(you)(you)(you)箱(xiang)內部(bu)發生故障(zhang)一般(ban)會(hui)引起(qi)油(you)(you)(you)面降低，瓦(wa)斯(si)繼電(dian)(dian)器(qi)的(de)能(neng)(neng)(neng)夠平衡錘的(de)力(li)(li)矩會(hui)發生變(bian)(bian)(bian)(bian)(bian)化而(er)降落，從而(er)接通上下觸點，自(zi)動(dong)發出(chu)報(bao)警(jing)(jing)信(xin)號。供電(dian)(dian)系(xi)(xi)統(tong)(tong)的(de)電(dian)(dian)力(li)(li)變(bian)(bian)(bian)(bian)(bian)壓(ya)器(qi)發生突發性(xing)的(de)嚴重(zhong)事(shi)故的(de)時候，也會(hui)有相應應對(dui)措(cuo)施。變(bian)(bian)(bian)(bian)(bian)壓(ya)器(qi)的(de)最(zui)嚴重(zhong)故障(zhang)為油(you)(you)(you)箱(xiang)漏(lou)油(you)(you)(you)，油(you)(you)(you)箱(xiang)漏(lou)油(you)(you)(you)會(hui)使(shi)變(bian)(bian)(bian)(bian)(bian)壓(ya)器(qi)發生爆炸(zha)，導致整(zheng)個(ge)供電(dian)(dian)系(xi)(xi)統(tong)(tong)癱瘓(huan)。漏(lou)油(you)(you)(you)使(shi)電(dian)(dian)力(li)(li)變(bian)(bian)(bian)(bian)(bian)壓(ya)器(qi)的(de)液面會(hui)發生較(jiao)大的(de)變(bian)(bian)(bian)(bian)(bian)化，繼電(dian)(dian)器(qi)的(de)上下觸點也能(neng)(neng)(neng)夠接觸，初步實現(xian)自(zi)動(dong)報(bao)警(jing)(jing)。隨(sui)著(zhu)漏(lou)油(you)(you)(you)的(de)繼續，油(you)(you)(you)位降低到一定(ding)數值，繼電(dian)(dian)器(qi)能(neng)(neng)(neng)夠自(zi)動(dong)跳閘(zha)保(bao)護(hu)整(zheng)個(ge)供電(dian)(dian)系(xi)(xi)統(tong)(tong)，避免大的(de)損失(shi)產生。供電(dian)(dian)系(xi)(xi)統(tong)(tong)的(de)電(dian)(dian)力(li)(li)變(bian)(bian)(bian)(bian)(bian)壓(ya)器(qi)大多在0.8MVA以上，都應該配備瓦(wa)斯(si)保(bao)護(hu)裝置(zhi)。

2.差動保護

供(gong)電(dian)(dian)系(xi)統的(de)(de)變壓(ya)器內(nei)部(bu)引出(chu)(chu)線短路(lu)，絕緣(yuan)套管相間(jian)短路(lu)故(gu)障(zhang)(zhang)發生(sheng)(sheng)(sheng)(sheng)時(shi)(shi)，變壓(ya)器內(nei)的(de)(de)匝間(jian)出(chu)(chu)現問(wen)題時(shi)(shi)，繼(ji)電(dian)(dian)系(xi)統都會及時(shi)(shi)啟動(dong)(dong)(dong)電(dian)(dian)流速斷保(bao)護(hu)(hu)(hu)(hu)(hu)。電(dian)(dian)流速斷保(bao)護(hu)(hu)(hu)(hu)(hu)的(de)(de)主要優(you)勢(shi)是能夠準(zhun)確(que)的(de)(de)定位(wei)故(gu)障(zhang)(zhang)發生(sheng)(sheng)(sheng)(sheng)的(de)(de)位(wei)置，及時(shi)(shi)分析(xi)出(chu)(chu)發生(sheng)(sheng)(sheng)(sheng)故(gu)障(zhang)(zhang)的(de)(de)類型，然后馬上(shang)調用內(nei)部(bu)已經(jing)編(bian)訂好的(de)(de)程(cheng)序，根據故(gu)障(zhang)(zhang)的(de)(de)情況(kuang)發出(chu)(chu)相應的(de)(de)預警措施。如(ru)果故(gu)障(zhang)(zhang)程(cheng)度(du)比(bi)較輕，差動(dong)(dong)(dong)保(bao)護(hu)(hu)(hu)(hu)(hu)可以預警后并延長故(gu)障(zhang)(zhang)繼(ji)續發生(sheng)(sheng)(sheng)(sheng)的(de)(de)時(shi)(shi)間(jian)，為專業人員(yuan)的(de)(de)維(wei)修提供(gong)一定的(de)(de)時(shi)(shi)間(jian)差，同時(shi)(shi)差動(dong)(dong)(dong)保(bao)護(hu)(hu)(hu)(hu)(hu)還可以利用已經(jing)編(bian)好的(de)(de)程(cheng)序，對小型故(gu)障(zhang)(zhang)進(jin)行自動(dong)(dong)(dong)的(de)(de)排除等。如(ru)果故(gu)障(zhang)(zhang)程(cheng)度(du)比(bi)較嚴重(zhong)，差動(dong)(dong)(dong)保(bao)護(hu)(hu)(hu)(hu)(hu)會直接報(bao)警并且斷電(dian)(dian)，避(bi)免短路(lu)后經(jing)濟損失情況(kuang)的(de)(de)發生(sheng)(sheng)(sheng)(sheng)。由于差動(dong)(dong)(dong)保(bao)護(hu)(hu)(hu)(hu)(hu)具(ju)有以上(shang)的(de)(de)優(you)勢(shi)，目前供(gong)電(dian)(dian)系(xi)統廣泛采(cai)用該技術，它將成為未(wei)來繼(ji)電(dian)(dian)保(bao)護(hu)(hu)(hu)(hu)(hu)的(de)(de)一種趨勢(shi)。

3. 過電流保護

過(guo)(guo)電(dian)(dian)(dian)流(liu)保(bao)(bao)(bao)(bao)護(hu)(hu)(hu)是(shi)作為瓦斯保(bao)(bao)(bao)(bao)護(hu)(hu)(hu)和差動保(bao)(bao)(bao)(bao)護(hu)(hu)(hu)后(hou)備保(bao)(bao)(bao)(bao)護(hu)(hu)(hu)，可(ke)以(yi)(yi)(yi)(yi)準確反(fan)應出變(bian)壓器(qi)(qi)短(duan)路所導致(zhi)的(de)(de)過(guo)(guo)電(dian)(dian)(dian)流(liu)。過(guo)(guo)電(dian)(dian)(dian)流(liu)保(bao)(bao)(bao)(bao)護(hu)(hu)(hu)裝(zhuang)置(zhi)一(yi)(yi)般(ban)是(shi)裝(zhuang)在(zai)電(dian)(dian)(dian)力變(bian)壓器(qi)(qi)的(de)(de)電(dian)(dian)(dian)源側，并且根據變(bian)壓器(qi)(qi)的(de)(de)要求裝(zhuang)配(pei)(pei)(pei)不(bu)(bu)同的(de)(de)保(bao)(bao)(bao)(bao)護(hu)(hu)(hu)裝(zhuang)置(zhi)。升(sheng)降壓變(bian)壓器(qi)(qi)處(chu)可(ke)以(yi)(yi)(yi)(yi)裝(zhuang)配(pei)(pei)(pei)復(fu)合電(dian)(dian)(dian)壓起動的(de)(de)過(guo)(guo)電(dian)(dian)(dian)流(liu)保(bao)(bao)(bao)(bao)護(hu)(hu)(hu)，大接地電(dian)(dian)(dian)流(liu)系(xi)統中，可(ke)以(yi)(yi)(yi)(yi)在(zai)變(bian)壓器(qi)(qi)外部裝(zhuang)配(pei)(pei)(pei)零序電(dian)(dian)(dian)流(liu)保(bao)(bao)(bao)(bao)護(hu)(hu)(hu)，作為主變(bian)壓器(qi)(qi)保(bao)(bao)(bao)(bao)護(hu)(hu)(hu)的(de)(de)后(hou)備保(bao)(bao)(bao)(bao)護(hu)(hu)(hu)。過(guo)(guo)電(dian)(dian)(dian)流(liu)保(bao)(bao)(bao)(bao)護(hu)(hu)(hu)的(de)(de)具體啟動方式應該根據相(xiang)配(pei)(pei)(pei)備的(de)(de)變(bian)電(dian)(dian)(dian)器(qi)(qi)的(de)(de)相(xiang)應數據進行(xing)合理選擇，沒有統一(yi)(yi)的(de)(de)標準，可(ke)以(yi)(yi)(yi)(yi)根據供電(dian)(dian)(dian)系(xi)統的(de)(de)不(bu)(bu)同需求裝(zhuang)配(pei)(pei)(pei)不(bu)(bu)同的(de)(de) 過(guo)(guo)電(dian)(dian)(dian)流(liu)保(bao)(bao)(bao)(bao)護(hu)(hu)(hu)裝(zhuang)置(zhi)。

4.過勵磁保護

現(xian)代供電(dian)系統由(you)與工作電(dian)壓(ya)過高(gao)(gao)(gao)，電(dian)力變(bian)壓(ya)器的(de)額定(ding)磁密接近飽和。頻率降低時(shi)與電(dian)壓(ya)升(sheng)高(gao)(gao)(gao)時(shi)，變(bian)壓(ya)器都很容易出(chu)現(xian)過勵(li)磁，導致鐵心的(de)溫度上(shang)升(sheng)影(ying)響絕緣性(xing)能。安裝勵(li)磁保(bao)護裝置，可(ke)將變(bian)壓(ya)器的(de)過勵(li)磁引起(qi)的(de)過電(dian)流反映出(chu)來，從而可(ke)防止變(bian)壓(ya)器絕緣老化，提高(gao)(gao)(gao)變(bian)壓(ya)器的(de)使(shi)用效能。

5.過負荷保護

過(guo)(guo)負(fu)荷(he)保(bao)護能(neng)夠反應變壓(ya)器(qi)正(zheng)常運行(xing)時(shi)所(suo)出現的過(guo)(guo)負(fu)荷(he)情況。過(guo)(guo)負(fu)荷(he)裝置僅在(zai)變壓(ya)器(qi)有可(ke)能(neng)過(guo)(guo)負(fu)荷(he)的情況下才裝設，通常能(neng)夠檢(jian)測出過(guo)(guo)負(fu)荷(he)的信號(hao)(hao)。它的基本工作(zuo)原理為：一(yi)相上進行(xing)一(yi)個電(dian)流繼電(dian)器(qi)的裝設，并經過(guo)(guo)一(yi)定時(shi)間延(yan)長動(dong)作(zuo)于信號(hao)(hao)來進行(xing)過(guo)(guo)負(fu)荷(he)保(bao)護

四、結論

供(gong)電(dian)(dian)系統的(de)電(dian)(dian)力變壓器由于運行時的(de)各種(zhong)因素產生(sheng)故(gu)障(zhang)，對供(gong)電(dian)(dian)系統的(de)安全(quan)與穩(wen)定(ding)造(zao)成影響(xiang)。許(xu)多隱性的(de)故(gu)障(zhang)人工(gong)排(pai)除比較(jiao)困難，突發(fa)性的(de)嚴(yan)重(zhong)故(gu)障(zhang)會造(zao)成巨(ju)大的(de)經濟損失，必(bi)須要有好的(de)繼電(dian)(dian)保(bao)護(hu)促(cu)使(shi)才能避免損失。而事實證(zheng)明，繼電(dian)(dian)保(bao)護(hu)裝置(zhi)措施(shi)可以(yi)改善(shan)變壓器嚴(yan)重(zhong)故(gu)障(zhang)發(fa)生(sheng)概率，對于隱性故(gu)障(zhang)能夠起到(dao)報(bao)警(jing)作用。研究(jiu)和(he)應(ying)用繼電(dian)(dian)保(bao)護(hu)措施(shi)，可以(yi)促(cu)進供(gong)電(dian)(dian)系統的(de)穩(wen)定(ding)與安全(quan)。

參考文獻：

[1] 丁(ding)永生(sheng). 10kV供電(dian)(dian)系統中變壓(ya)器繼電(dian)(dian)保護分析(xi)[J],中國新技術產品,2009（23）

篇6

【關鍵(jian)詞】變壓器故障 繼電(dian)保護(hu)(hu)技術(shu) 電(dian)氣量保護(hu)(hu)配(pei)置(zhi)

電(dian)(dian)力變(bian)壓(ya)(ya)(ya)器(qi)(qi)(qi)(qi)(qi)(qi)作為電(dian)(dian)力系統中的(de)(de)(de)(de)關鍵(jian)設(she)備，是保(bao)證電(dian)(dian)力系統安(an)全運行的(de)(de)(de)(de)基礎，如(ru)果變(bian)壓(ya)(ya)(ya)器(qi)(qi)(qi)(qi)(qi)(qi)出現故障時，保(bao)護裝置不能(neng)(neng)再規定(ding)的(de)(de)(de)(de)時間(jian)內快(kuai)速完(wan)成動作，有可能(neng)(neng)會(hui)導致變(bian)壓(ya)(ya)(ya)器(qi)(qi)(qi)(qi)(qi)(qi)被(bei)(bei)損壞，嚴(yan)重時會(hui)導致變(bian)壓(ya)(ya)(ya)器(qi)(qi)(qi)(qi)(qi)(qi)被(bei)(bei)燒毀(hui)，由于變(bian)壓(ya)(ya)(ya)器(qi)(qi)(qi)(qi)(qi)(qi)工作過程中有一定(ding)的(de)(de)(de)(de)局限性，當斷路器(qi)(qi)(qi)(qi)(qi)(qi)和互感器(qi)(qi)(qi)(qi)(qi)(qi)之間(jian)出現故障且無(wu)法及時消(xiao)除(chu)時，會(hui)對(dui)變(bian)壓(ya)(ya)(ya)器(qi)(qi)(qi)(qi)(qi)(qi)造(zao)成比(bi)較大的(de)(de)(de)(de)影(ying)響，對(dui)于這(zhe)種(zhong)情況可以選擇低壓(ya)(ya)(ya)開(kai)關輔助(zhu)的(de)(de)(de)(de)方(fang)法來(lai)對(dui)外(wai)部結構進行更改，進而達到消(xiao)除(chu)故障的(de)(de)(de)(de)目的(de)(de)(de)(de)。

1 電(dian)(dian)力變壓器(qi)繼電(dian)(dian)保護裝(zhuang)置的基本含義(yi)

電(dian)(dian)(dian)力變壓器(qi)(qi)繼電(dian)(dian)(dian)保(bao)護裝置的(de)主要(yao)作用(yong)是(shi)確保(bao)電(dian)(dian)(dian)力系(xi)統穩(wen)定運行，給予(yu)用(yong)戶提供可靠和安(an)全(quan)的(de)供電(dian)(dian)(dian)服務(wu)，其中電(dian)(dian)(dian)力變壓器(qi)(qi)繼電(dian)(dian)(dian)保(bao)護的(de)主要(yao)功能(neng)有以下幾點。

（1）一旦電力變壓器系(xi)統產生動(dong)作信(xin)(xin)號或者故障(zhang)信(xin)(xin)息就能夠快速做出回應，確保繼電保護功能和設計能力能夠充分發揮出來。

（2）若是變壓器(qi)產生(sheng)異常問(wen)(wen)(wen)題或(huo)者(zhe)故(gu)障(zhang)問(wen)(wen)(wen)題時，能夠(gou)迅(xun)速命(ming)令繼電(dian)保護(hu)動作(zuo)將(jiang)電(dian)力變壓器(qi)切點，并隔離線路異常問(wen)(wen)(wen)題和故(gu)障(zhang)問(wen)(wen)(wen)題，減(jian)少故(gu)障(zhang)事故(gu)帶來的影(ying)響。

（3）電力(li)變壓器繼(ji)電保護能夠減少異常問題(ti)或者(zhe)故障問題(ti)帶來(lai)的(de)(de)經濟損(sun)失，確保電網和電力(li)變壓器運行的(de)(de)經濟性和穩定性。

電(dian)力變壓器繼(ji)電(dian)保(bao)護裝置主要具有(you)四種性(xing)(xing)(xing)能，即靈敏(min)、快(kuai)速、可(ke)靠(kao)(kao)以及(ji)選擇等多種性(xing)(xing)(xing)質(zhi)。其中靈敏(min)性(xing)(xing)(xing)是指繼(ji)電(dian)保(bao)護對于設(she)備(bei)設(she)定(ding)的(de)動作(zuo)故(gu)障和(he)相關異(yi)(yi)常情況能夠及(ji)時可(ke)靠(kao)(kao)的(de)完成中斷動作(zuo)。而繼(ji)電(dian)保(bao)護裝置的(de)快(kuai)速性(xing)(xing)(xing)則是指設(she)備(bei)在發(fa)生故(gu)障時能夠以最快(kuai)的(de)速度促(cu)使斷路器跳閘，從而斷開故(gu)障，終止(zhi)異(yi)(yi)常狀(zhuang)態。繼(ji)電(dian)保(bao)護裝置的(de)可(ke)靠(kao)(kao)性(xing)(xing)(xing)則主要劃分為兩種形式，即可(ke)信(xin)賴性(xing)(xing)(xing)和(he)安全性(xing)(xing)(xing)，其中可(ke)信(xin)賴性(xing)(xing)(xing)是指繼(ji)電(dian)保(bao)護在正常動作(zuo)過程(cheng)中出現異(yi)(yi)常或者(zhe)故(gu)障時，能夠及(ji)時準確的(de)完成既定(ding)動作(zuo)，安全性(xing)(xing)(xing)是要求繼(ji)電(dian)保(bao)護在非設(she)計(ji)狀(zhuang)態下，能夠立即停止(zhi)動作(zuo)，從而將損失降(jiang)至最低。

2 電(dian)氣量保護配置分析

2.1 差動保護

在變壓器的(de)諧波閉(bi)鎖(suo)差動保(bao)(bao)護中，涉及到的(de)絕(jue)大(da)多數都是啟動和差動元件，其主(zhu)要(yao)囊括諧波制動和異(yi)常判定(ding)以及其他(ta)等多種(zhong)元件。而繼(ji)電保(bao)(bao)護裝(zhuang)置的(de)保(bao)(bao)護過程主(zhu)要(yao)劃分為以下(xia)幾個方面：

（1）對于啟(qi)(qi)動(dong)(dong)元件(jian)的使(shi)(shi)用(yong)，其(qi)主要包含差流突(tu)變(bian)量(liang)和(he)超(chao)限(xian)兩種元件(jian)，在實際使(shi)(shi)用(yong)過(guo)程中如果差電流產生變(bian)動(dong)(dong)并且持續性的超(chao)過(guo)啟(qi)(qi)動(dong)(dong)電流時(shi)(shi)，便(bian)是(shi)立即(ji)激發啟(qi)(qi)動(dong)(dong)保護(hu)動(dong)(dong)作。而朝(chao)鮮元件(jian)在差動(dong)(dong)電流在差動(dong)(dong)電流超(chao)過(guo)超(chao)限(xian)啟(qi)(qi)動(dong)(dong)電流并且超(chao)過(guo)5ms時(shi)(shi)，則會(hui)立即(ji)啟(qi)(qi)動(dong)(dong)保護(hu)動(dong)(dong)作。

（2）對于差動(dong)元(yuan)件的使用(yong)，其主要作用(yong)時在變壓器產生故障(zhang)或者線路異常時，能(neng)夠實現快速切斷電(dian)路的基本(ben)功能(neng)。

（3）而(er)(er)諧(xie)波(bo)元件的(de)基(ji)本(ben)(ben)作用時(shi)變壓(ya)器在空投狀態是能夠有(you)效避免勵磁涌流(liu)所產(chan)生的(de)差動(dong)保護錯誤動(dong)作，而(er)(er)動(dong)作產(chan)生的(de)依據其實是差流(liu)中二(er)次諧(xie)波(bo)分量電流(liu)和基(ji)波(bo)分量電流(liu)的(de)基(ji)本(ben)(ben)比例。

（4）比率(lv)制動(dong)(dong)(dong)部(bu)件。比率(lv)制動(dong)(dong)(dong)部(bu)件的(de)主要作用是指變壓器外部(bu)產生(sheng)故(gu)障，差動(dong)(dong)(dong)保護便(bian)能夠立即啟動(dong)(dong)(dong)制動(dong)(dong)(dong)功能，減少故(gu)障問題的(de)影響范(fan)圍，并(bing)且比率(lv)制動(dong)(dong)(dong)部(bu)件對于內部(bu)故(gu)障具有較(jiao)高的(de)靈(ling)敏度(du)。

（5）過(guo)負荷(he)通過(guo)泠卻器產生的(de)變壓器負荷(he)，能夠準(zhun)確(que)的(de)檢測到高壓側的(de)電流。

2.2 波形差動保護

波(bo)形(xing)(xing)差(cha)動(dong)保護和諧(xie)波(bo)制動(dong)的主要區(qu)別(bie)在(zai)于二(er)次諧(xie)波(bo)，在(zai)變(bian)壓器空(kong)載運行的狀態(tai)下，利用波(bo)形(xing)(xing)算法，計(ji)算合閘(zha)生成的勵磁涌流與(yu)故障電(dian)流。如(ru)果空(kong)載合閘(zha)產生內部故障或者外部故障，波(bo)形(xing)(xing)差(cha)動(dong)保護會(hui)立即啟動(dong)，并確保電(dian)力系統的安全和穩定(ding)。

而差(cha)動保(bao)(bao)護(hu)則(ze)主(zhu)(zhu)要(yao)囊括有流互感器(qi)(qi)中的(de)各種設備(bei)，在內部產生(sheng)故障時(shi)(shi)則(ze)會(hui)(hui)立即跳開主(zhu)(zhu)變(bian)兩側(ce)(ce)的(de)斷路(lu)器(qi)(qi)。而兩側(ce)(ce)的(de)后(hou)背(bei)保(bao)(bao)護(hu)則(ze)主(zhu)(zhu)要(yao)包(bao)括差(cha)動后(hou)背(bei)保(bao)(bao)護(hu)和(he)母線保(bao)(bao)護(hu)，在保(bao)(bao)護(hu)指令(ling)和(he)動作(zuo)過程中會(hui)(hui)延時(shi)(shi)跳開斷路(lu)器(qi)(qi)。在主(zhu)(zhu)變(bian)經過投產和(he)檢修之后(hou)，為(wei)了快(kuai)速和(he)有效的(de)斷開主(zhu)(zhu)變(bian)，應(ying)當(dang)嚴格按照(zhao)相關(guan)設備(bei)操作(zuo)要(yao)求進行。

2.3 后備保護

后備(bei)保護(hu)在實際運行中由于受到主變(bian)阻(zu)抗的(de)影(ying)響，當低壓(ya)側(ce)產生(sheng)異常問題或者(zhe)故障時，則高(gao)壓(ya)側(ce)電壓(ya)可能變(bian)小，因此(ci)導致難以迅速(su)啟(qi)(qi)動(dong)電壓(ya)閉(bi)鎖。通常情況下使(shi)用高(gao)、低壓(ya)側(ce)的(de)并(bing)聯方式來提高(gao)故障狀態下啟(qi)(qi)動(dong)動(dong)作(zuo)的(de)靈敏性和快速(su)性，確保低壓(ya)側(ce)產生(sheng)故障過程(cheng)中能夠迅速(su)啟(qi)(qi)動(dong)保護(hu)動(dong)作(zuo)。此(ci)外還可以通過高(gao)、低壓(ya)側(ce)電壓(ya)，高(gao)低兩側(ce)動(dong)作(zuo)都可以快速(su)啟(qi)(qi)動(dong)閉(bi)鎖回路。

2.4 零序過(guo)流保護

在接地故障產(chan)生時，借助零序(xu)過(guo)(guo)流保(bao)(bao)(bao)護能夠對(dui)變壓器形成后背保(bao)(bao)(bao)護，而(er)交流應當選(xuan)擇專有接線，并且電(dian)(dian)壓和電(dian)(dian)流分別采取該(gai)(gai)側的(de)TV和TA。而(er)TV如果產(chan)生斷線情況，零序(xu)過(guo)(guo)流保(bao)(bao)(bao)護將會即(ji)刻關閉(bi)。在電(dian)(dian)壓恢復正常(chang)(chang)之(zhi)后，零序(xu)過(guo)(guo)流保(bao)(bao)(bao)護則會立(li)即(ji)恢復正常(chang)(chang)，并投入使用。借助該(gai)(gai)種(zhong)方式能夠將間(jian)隙(xi)保(bao)(bao)(bao)護的(de)作用發揮到(dao)最大。

3 分析主(zhu)變保護的主(zhu)要故障(zhang)

3.1 分析變壓器操作過程中產生的(de)主(zhu)要(yao)故障

變(bian)(bian)(bian)(bian)壓(ya)(ya)器(qi)在(zai)(zai)工作(zuo)過程(cheng)中(zhong)，其檢修復役的(de)主要操作(zuo)過程(cheng)為(wei)：當(dang)低(di)(di)壓(ya)(ya)側(ce)(ce)斷路(lu)(lu)器(qi)斷開時(shi)，則合上(shang)(shang)高壓(ya)(ya)側(ce)(ce)斷路(lu)(lu)器(qi)迅(xun)(xun)速沖(chong)擊(ji)主變(bian)(bian)(bian)(bian)，完成主變(bian)(bian)(bian)(bian)沖(chong)擊(ji)之(zhi)后會迅(xun)(xun)速合上(shang)(shang)低(di)(di)壓(ya)(ya)側(ce)(ce)斷路(lu)(lu)器(qi)，然后再送(song)出負荷。若在(zai)(zai)沖(chong)擊(ji)主變(bian)(bian)(bian)(bian)過程(cheng)中(zhong)低(di)(di)壓(ya)(ya)側(ce)(ce)斷路(lu)(lu)器(qi)與電(dian)(dian)流互(hu)感器(qi)產生短路(lu)(lu)故障，則差動(dong)保護(hu)無(wu)法正(zheng)(zheng)常啟動(dong)跳(tiao)閘命令(ling)。并(bing)且高壓(ya)(ya)側(ce)(ce)后備保護(hu)的(de)高壓(ya)(ya)側(ce)(ce)母(mu)(mu)線電(dian)(dian)壓(ya)(ya)因(yin)為(wei)主變(bian)(bian)(bian)(bian)阻抗相對較大，所以難以正(zheng)(zheng)常啟動(dong)跳(tiao)閘命令(ling)，而低(di)(di)壓(ya)(ya)側(ce)(ce)母(mu)(mu)線因(yin)為(wei)電(dian)(dian)壓(ya)(ya)正(zheng)(zheng)常所以也無(wu)法利(li)用并(bing)聯啟動(dong)回路(lu)(lu)保護(hu)高壓(ya)(ya)側(ce)(ce)，無(wu)法迅(xun)(xun)速切除線路(lu)(lu)故障，從而產生主變(bian)(bian)(bian)(bian)燒毀損壞的(de)現象，這就是主變(bian)(bian)(bian)(bian)保護(hu)的(de)盲(mang)區，如圖1所示。

3.2 對變壓(ya)器(qi)運行中所產生的(de)故障進(jin)行分(fen)析

變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)器(qi)在(zai)實(shi)(shi)際運行中，如(ru)果低壓(ya)(ya)(ya)(ya)(ya)(ya)側(ce)斷(duan)(duan)路(lu)器(qi)與電(dian)(dian)流(liu)互感器(qi)之間產生故(gu)障(zhang)問題或者異常狀況，變(bian)(bian)(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)器(qi)低壓(ya)(ya)(ya)(ya)(ya)(ya)側(ce)保護必須在(zai)低壓(ya)(ya)(ya)(ya)(ya)(ya)側(ce)母線(xian)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)降低與電(dian)(dian)流(liu)增大(da)兩個條件下，通(tong)過較短(duan)時延動(dong)作跳開主變(bian)(bian)(bian)低壓(ya)(ya)(ya)(ya)(ya)(ya)側(ce)斷(duan)(duan)路(lu)器(qi)，確保低壓(ya)(ya)(ya)(ya)(ya)(ya)側(ce)母線(xian)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)穩定和正常。而實(shi)(shi)際上故(gu)障(zhang)點(dian)沒(mei)有(you)得到隔離，并(bing)且短(duan)路(lu)電(dian)(dian)流(liu)由高(gao)(gao)壓(ya)(ya)(ya)(ya)(ya)(ya)側(ce)母線(xian)經(jing)過主變(bian)(bian)(bian)向故(gu)障(zhang)點(dian)進行輸送，盡(jin)管高(gao)(gao)壓(ya)(ya)(ya)(ya)(ya)(ya)側(ce)故(gu)障(zhang)電(dian)(dian)流(liu)相對大(da)，但是高(gao)(gao)壓(ya)(ya)(ya)(ya)(ya)(ya)側(ce)電(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)受到主變(bian)(bian)(bian)阻抗(kang)影響，難(nan)以啟動(dong)可靠動(dong)作，因(yin)此無法快速清除故(gu)障(zhang)，從而產生保護盲區。

4 有(you)效(xiao)避免主變故障的方法

4.1 不(bu)斷優化高(gao)壓側后備保護動作(zuo)邏輯

為了有(you)效(xiao)減少主(zhu)變(bian)故障可(ke)以(yi)不斷(duan)優化(hua)高壓(ya)(ya)側(ce)后(hou)備保護(hu)動作(zuo)，在(zai)兩(liang)圈變(bian)壓(ya)(ya)器主(zhu)變(bian)高壓(ya)(ya)后(hou)備保護(hu)中添加與門(men)電路(lu)(lu)，動作(zuo)邏輯(ji)是：若低壓(ya)(ya)側(ce)斷(duan)路(lu)(lu)器已經斷(duan)開時，高壓(ya)(ya)側(ce)電流比規定數值較大，則根(gen)據規定時間跳(tiao)高壓(ya)(ya)側(ce)斷(duan)路(lu)(lu)器，動作(zuo)邏輯(ji)電路(lu)(lu)如圖(tu)2。

同時(shi)，在三圈變(bian)壓(ya)器主變(bian)高壓(ya)后(hou)備保(bao)護中添加與(yu)門電路，動作邏(luo)輯是：若低(di)壓(ya)側(ce)斷(duan)路器或(huo)者(zhe)中壓(ya)側(ce)斷(duan)路器已經斷(duan)開時(shi)，而(er)高壓(ya)側(ce)電流比規定值大，那么就需要(yao)根據固定時(shi)間跳高、中、低(di)壓(ya)斷(duan)路器。

4.2 不斷優化(hua)中(zhong)低壓側后備保護(hu)動(dong)作(zuo)邏(luo)輯

在(zai)兩圈變(bian)壓(ya)(ya)器(qi)(qi)主(zhu)變(bian)低壓(ya)(ya)后備保(bao)護(hu)中(zhong)(zhong)添加(jia)與門(men)電(dian)(dian)路(lu)(lu)，動(dong)作(zuo)邏(luo)輯是：若低壓(ya)(ya)側斷(duan)(duan)路(lu)(lu)器(qi)(qi)已經(jing)(jing)斷(duan)(duan)開，而(er)(er)低壓(ya)(ya)側電(dian)(dian)流比規(gui)定(ding)值(zhi)大(da)，那么就(jiu)需要根(gen)據規(gui)定(ding)時(shi)間跳高(gao)壓(ya)(ya)側斷(duan)(duan)路(lu)(lu)器(qi)(qi)；然后再在(zai)三圈變(bian)壓(ya)(ya)器(qi)(qi)主(zhu)變(bian)中(zhong)(zhong)壓(ya)(ya)后備保(bao)護(hu)中(zhong)(zhong)添加(jia)與門(men)電(dian)(dian)路(lu)(lu)，動(dong)作(zuo)邏(luo)輯是：若中(zhong)(zhong)壓(ya)(ya)側斷(duan)(duan)路(lu)(lu)器(qi)(qi)已經(jing)(jing)斷(duan)(duan)開，而(er)(er)中(zhong)(zhong)壓(ya)(ya)側電(dian)(dian)流比規(gui)定(ding)值(zhi)大(da)，那么就(jiu)需要根(gen)據規(gui)定(ding)時(shi)間跳高(gao)、中(zhong)(zhong)壓(ya)(ya)側斷(duan)(duan)路(lu)(lu)器(qi)(qi)。

5 注意(yi)事項(xiang)與應對策略

（1）在兩圈變壓(ya)器(qi)中，當檢修(xiu)低(di)壓(ya)側(ce)(ce)斷路器(qi)時，高(gao)壓(ya)側(ce)(ce)斷路器(qi)與主變正(zheng)在運行(xing)，需要(yao)在高(gao)壓(ya)側(ce)(ce)斷路器(qi)安裝(zhuang)低(di)壓(ya)側(ce)(ce)斷路器(qi)位置輸入(ru)壓(ya)板，以免低(di)壓(ya)側(ce)(ce)斷路器(qi)位置產生變化導致高(gao)壓(ya)側(ce)(ce)出現誤判(pan)現象。

（2）在(zai)三圈變壓器中(zhong)，不僅需(xu)(xu)要對低(di)(di)壓側斷(duan)路器冷備用和檢修(xiu)問題進行考慮，還(huan)需(xu)(xu)要對高中(zhong)低(di)(di)壓側斷(duan)路器運行狀(zhuang)態進行綜(zong)合(he)考慮，同(tong)時中(zhong)低(di)(di)壓側斷(duan)路器熱(re)備用狀(zhuang)態極易產生線路短(duan)路狀(zhuang)況，迫使高壓側保護過流動作，迅速做(zuo)出跳(tiao)開動作。其(qi)中(zhong)，改變中(zhong)低(di)(di)壓側保護邏輯與接線能夠(gou)有(you)效實現變壓器動作的時限配合(he)。

6 結論

綜上所述(shu)，為(wei)了(le)保(bao)證變(bian)(bian)壓器(qi)安(an)全穩定的(de)(de)運行，在原有(you)的(de)(de)變(bian)(bian)電(dian)系統中(zhong)除(chu)了(le)要安(an)裝繼電(dian)保(bao)護設備以外，還需(xu)要增設門(men)電(dian)路輔助或復(fu)合電(dian)壓閉鎖，通過對對變(bian)(bian)壓器(qi)內部邏輯判據和變(bian)(bian)壓器(qi)外部接線(xian)進行調整來達到消除(chu)故障的(de)(de)目的(de)(de)，保(bao)證電(dian)力系統可以穩定、安(an)全的(de)(de)運行。

參考文獻

[1]陳新，呂飛鵬，蔣科，等.基于多技術的(de)智能電(dian)網繼(ji)電(dian)保(bao)護在線整定系(xi)統[J].電(dian)力系(xi)統保(bao)護與(yu)控制，2010，38（18）：167-173.

[2]龍波，艾昶(chang)恩，曹揚(yang).變(bian)壓器(qi)(qi)繼電保護技術(shu)及配置(zhi)方案研究[J].儀器(qi)(qi)儀表用戶，2014（05）：37-40.

[3]王世閣，鐘洪(hong)壁.電(dian)力變(bian)壓器故障分析與技術改進(jin)[M].北京：中(zhong)國電(dian)力出版社，2004.

作者簡介

王海峰(feng)（1979-），男，山東省濟南市人。大學(xue)本科學(xue)歷。現為(wei)華(hua)電章丘發電有限公司助理工程師(shi)，從(cong)事發電設(she)備(bei)管理工作。

篇7

關鍵詞(ci)：110kV變電(dian)站 接地變壓器(qi)保護 誤動(dong)原因 措施

近年(nian)來，城市(shi)110kV變(bian)電(dian)(dian)(dian)站(zhan)10kV饋(kui)線大量采(cai)用地(di)下電(dian)(dian)(dian)纜，導(dao)致系(xi)統電(dian)(dian)(dian)容(rong)量大大增加(jia)。而當兩條(tiao)饋(kui)線同一相先后發(fa)生(sheng)高阻接地(di)時(shi)，電(dian)(dian)(dian)流(liu)(liu)的(de)疊加(jia)會造成(cheng)(cheng)變(bian)壓器零序(xu)電(dian)(dian)(dian)流(liu)(liu)保(bao)(bao)護誤動(dong)，目前電(dian)(dian)(dian)力部門解決保(bao)(bao)護誤動(dong)的(de)思路是加(jia)裝接地(di)變(bian)壓器來構成(cheng)(cheng)低阻接地(di)接線方式，形成(cheng)(cheng)一條(tiao)零序(xu)電(dian)(dian)(dian)流(liu)(liu)的(de)通道，以(yi)便(bian)當10kV系(xi)統發(fa)生(sheng)接地(di)時(shi)，根據接地(di)點所在(zai)位置，由相應零序(xu)保(bao)(bao)護有選擇(ze)性動(dong)作將接地(di)故障隔離，以(yi)防電(dian)(dian)(dian)弧重燃(ran)引發(fa)過電(dian)(dian)(dian)壓，保(bao)(bao)證電(dian)(dian)(dian)網設備安全供電(dian)(dian)(dian)。

本文選(xuan)取的(de)(de)某城市(shi)電(dian)(dian)(dian)網(wang)改(gai)造中實施(shi)了(le)(le)低阻接地接線(xian)方式，加裝了(le)(le)接地變(bian)壓(ya)(ya)器(qi)和接地變(bian)壓(ya)(ya)器(qi)保護設備，確(que)保了(le)(le)10kV系(xi)統(tong)任意饋線(xian)發生接地故障(zhang)時能快速切除故障(zhang)，降低對(dui)電(dian)(dian)(dian)網(wang)沖擊的(de)(de)可能性。不過(guo)，隨著用(yong)電(dian)(dian)(dian)負荷加大以(yi)及后(hou)期維護方面原因(yin)，該電(dian)(dian)(dian)網(wang)系(xi)統(tong)陸續出現(xian)多(duo)次接地變(bian)壓(ya)(ya)器(qi)保護誤動事故，干擾到了(le)(le)電(dian)(dian)(dian)網(wang)系(xi)統(tong)的(de)(de)穩定運行，給周圍用(yong)戶帶來的(de)(de)麻煩。本文筆者結合多(duo)年的(de)(de)電(dian)(dian)(dian)力系(xi)統(tong)工作(zuo)經驗，以(yi)選(xuan)取上述城市(shi)變(bian)壓(ya)(ya)器(qi)系(xi)統(tong)改(gai)造為例分(fen)析(xi)了(le)(le)接地變(bian)壓(ya)(ya)器(qi)保護誤動發生的(de)(de)原因(yin)及解決措施(shi)，具有一定的(de)(de)借鑒價值(zhi)。

1、接地變壓器(qi)發生保(bao)護誤(wu)動原因

我們先看10KV饋線(xian)零序保(bao)護工作原理，流程圖如下(xia)：

從以上流程圖分析(xi)來看，三個節(jie)點(dian)零序CT、饋線保護和開關決定著接地變壓器能(neng)夠正常(chang)工(gong)作，倘若一(yi)個節(jie)點(dian)出現故障(zhang)，將導致(zhi)保護誤動事故發生，據(ju)此從以上三個節(jie)點(dian)來分析(xi)：

1.1 零序CT誤(wu)差(cha)引(yin)發保(bao)護誤(wu)動(dong)

當10KV饋(kui)(kui)(kui)(kui)線(xian)(xian)發生接(jie)地(di)短路故障時，故障線(xian)(xian)路零(ling)序(xu)CT檢測到(dao)故障電(dian)(dian)流(liu)，對應的饋(kui)(kui)(kui)(kui)線(xian)(xian)零(ling)序(xu)保(bao)護(hu)首先啟動切除(chu)故障線(xian)(xian)路，同時接(jie)地(di)變壓(ya)器(qi)的零(ling)序(xu)CT也檢測到(dao)故障電(dian)(dian)流(liu)，保(bao)護(hu)啟動，為了遵(zun)循選擇(ze)性的原則，實現(xian)10KV饋(kui)(kui)(kui)(kui)線(xian)(xian)保(bao)護(hu)優先動作，10KV饋(kui)(kui)(kui)(kui)線(xian)(xian)零(ling)序(xu)保(bao)護(hu)電(dian)(dian)流(liu)和(he)時間整定(ding)值要比接(jie)地(di)變壓(ya)器(qi)保(bao)護(hu)小(xiao)。根(gen)據現(xian)行變電(dian)(dian)站運(yun)行數(shu)據可知，接(jie)地(di)變：一次電(dian)(dian)流(liu)75A、1.5S切10KV分段(duan)、1.8S閉鎖10KV自投、2.0S切變低、2.5S切兩側；10KV饋(kui)(kui)(kui)(kui)線(xian)(xian)：一次電(dian)(dian)流(liu)60A、1.0S切開關。

但由于各(ge)種原因，CT難免有誤(wu)差(cha)(cha)(cha)，如果接(jie)地(di)變(bian)壓器的(de)零(ling)序CT-10%誤(wu)差(cha)(cha)(cha)，饋線的(de)零(ling)序CT+10%誤(wu)差(cha)(cha)(cha)，兩者的(de)實際(ji)電流動(dong)(dong)作值為(wei)67.5A和66A，幾乎相等，只依(yi)靠時間選擇，當(dang)發生(sheng)10KV饋線接(jie)地(di)時，就很容易造成接(jie)地(di)變(bian)零(ling)序過流越(yue)級動(dong)(dong)作。

1.2 電纜屏蔽(bi)層接地線錯誤引(yin)發保護誤動(dong)

110KV變(bian)電(dian)(dian)(dian)站(zhan)10KV饋線(xian)都采用帶屏(ping)(ping)蔽(bi)層的(de)電(dian)(dian)(dian)纜(lan)，且電(dian)(dian)(dian)纜(lan)屏(ping)(ping)蔽(bi)層在(zai)(zai)兩端同(tong)時接(jie)地，這是一(yi)種有(you)效的(de)電(dian)(dian)(dian)磁抗干擾措施(shi)，10KV饋線(xian)零(ling)序(xu)(xu)CT都是用穿(chuan)心式，零(ling)序(xu)(xu)CT穿(chuan)過(guo)電(dian)(dian)(dian)纜(lan)安(an)裝于開(kai)關(guan)柜(ju)電(dian)(dian)(dian)纜(lan)出線(xian)處(chu)，利用電(dian)(dian)(dian)磁感(gan)應(ying)原理，接(jie)地短路故障時產生的(de)不(bu)(bu)(bu)平衡電(dian)(dian)(dian)流，在(zai)(zai)零(ling)序(xu)(xu)CT上感(gan)應(ying)到電(dian)(dian)(dian)流從而(er)使保(bao)護裝置(zhi)動(dong)作，然而(er)，電(dian)(dian)(dian)纜(lan)屏(ping)(ping)蔽(bi)層兩端接(jie)地后(hou)，流過(guo)電(dian)(dian)(dian)纜(lan)屏(ping)(ping)蔽(bi)層的(de)感(gan)應(ying)電(dian)(dian)(dian)流也將會在(zai)(zai)零(ling)序(xu)(xu)CT上感(gan)應(ying)到電(dian)(dian)(dian)流，如果(guo)不(bu)(bu)(bu)采取措施(shi)，將影響到饋線(xian)零(ling)序(xu)(xu)保(bao)護不(bu)(bu)(bu)能正確動(dong)作，從而(er)引起接(jie)地變(bian)壓(ya)器(qi)保(bao)護越級動(dong)作見圖1。

1.3 10KV饋(kui)線保護(hu)拒動導致(zhi)保護(hu)誤動

目前電(dian)網系統廣泛應用微機(ji)型保(bao)(bao)護(hu)(hu)裝(zhuang)置，保(bao)(bao)護(hu)(hu)性(xing)能大(da)(da)大(da)(da)提高，但保(bao)(bao)護(hu)(hu)裝(zhuang)置生產廠商和型號也(ye)比較多(duo)，產品質量(liang)和技術參差不一(yi)，散熱(re)能力差也(ye)是其一(yi)大(da)(da)弊端(duan)，裝(zhuang)置故障(zhang)(zhang)(zhang)時(shi)有發生，從110KV變電(dian)站(zhan)保(bao)(bao)護(hu)(hu)設備故障(zhang)(zhang)(zhang)統計表(biao)明，10KV饋線保(bao)(bao)護(hu)(hu)裝(zhuang)置的電(dian)源插(cha)件、采樣插(cha)件、CPU插(cha)件和跳閘出口插(cha)件最容易出現故障(zhang)(zhang)(zhang)。所以一(yi)旦它們出現故障(zhang)(zhang)(zhang)又未即時(shi)處(chu)理(li)，保(bao)(bao)護(hu)(hu)有可能拒動，造成接地變壓器(qi)保(bao)(bao)護(hu)(hu)誤動。

1.4 10KV饋線開關(guan)拒動導致(zhi)保護誤動

近年來(lai)，由于(yu)使(shi)用時限長、操(cao)作(zuo)次數多或(huo)是本(ben)身(shen)的(de)質量問題(ti)，發(fa)生在(zai)10KV開(kai)關(guan)柜上(shang)的(de)故(gu)(gu)障(zhang)(zhang)越(yue)來(lai)越(yue)多，其中開(kai)關(guan)控制回路的(de)故(gu)(gu)障(zhang)(zhang)尤其突(tu)出，特別是一些(xie)欠發(fa)達的(de)山區，由于(yu)還有部分舊式開(kai)關(guan)柜（GG-1A型）仍在(zai)運行和發(fa)生接(jie)地故(gu)(gu)障(zhang)(zhang)機率較多。如果在(zai)開(kai)關(guan)柜故(gu)(gu)障(zhang)(zhang)期間出現饋(kui)線(xian)(xian)接(jie)地故(gu)(gu)障(zhang)(zhang)，即使(shi)零序(xu)保(bao)護正(zheng)確啟動(dong)，由于(yu)開(kai)關(guan)拒動(dong)也會造成接(jie)地變壓器保(bao)護誤動(dong)，從事故(gu)(gu)調查分析，饋(kui)線(xian)(xian)接(jie)地故(gu)(gu)障(zhang)(zhang)零序(xu)保(bao)護動(dong)作(zuo)，命(ming)令跳(tiao)開(kai)饋(kui)線(xian)(xian)開(kai)關(guan)，同時跳(tiao)閘線(xian)(xian)圈燒壞(huai)，開(kai)關(guan)不能(neng)動(dong)作(zuo)，是開(kai)關(guan)拒動(dong)的(de)主要原因。

1.5 10KV兩(liang)條饋線高(gao)阻接地(di)

當兩(liang)條(tiao)10KV饋(kui)線(xian)(xian)同(tong)相高(gao)阻接(jie)地(di)(di)(di)(di)時，兩(liang)條(tiao)10KV饋(kui)線(xian)(xian)保(bao)護(hu)(hu)只達(da)到(dao)告警值(zhi)，零(ling)(ling)序(xu)保(bao)護(hu)(hu)不動(dong)作，但有可能達(da)到(dao)接(jie)地(di)(di)(di)(di)變壓器(qi)(qi)(qi)保(bao)護(hu)(hu)動(dong)作值(zhi)，引起接(jie)地(di)(di)(di)(di)變壓器(qi)(qi)(qi)保(bao)護(hu)(hu)誤動(dong)，例如一(yi)(yi)饋(kui)線(xian)(xian)單相高(gao)阻接(jie)地(di)(di)(di)(di)，零(ling)(ling)序(xu)電(dian)(dian)(dian)流(liu)(liu)達(da)到(dao)40A，饋(kui)線(xian)(xian)零(ling)(ling)序(xu)保(bao)護(hu)(hu)不動(dong)作（動(dong)作值(zhi)為60A）；接(jie)著另一(yi)(yi)饋(kui)線(xian)(xian)也同(tong)一(yi)(yi)相高(gao)阻接(jie)地(di)(di)(di)(di)，零(ling)(ling)序(xu)電(dian)(dian)(dian)流(liu)(liu)達(da)到(dao)50A，零(ling)(ling)序(xu)電(dian)(dian)(dian)流(liu)(liu)未達(da)到(dao)60A，饋(kui)線(xian)(xian)零(ling)(ling)序(xu)保(bao)護(hu)(hu)也不動(dong)作；但電(dian)(dian)(dian)流(liu)(liu)疊加達(da)到(dao)90A，超過(guo)接(jie)地(di)(di)(di)(di)變壓器(qi)(qi)(qi)保(bao)護(hu)(hu)動(dong)作值(zhi)（動(dong)作值(zhi)為75A），將造成接(jie)地(di)(di)(di)(di)變壓器(qi)(qi)(qi)保(bao)護(hu)(hu)零(ling)(ling)序(xu)過(guo)流(liu)(liu)越級動(dong)作。

2、防(fang)止接地變壓(ya)器保護誤動(dong)的解(jie)決措施

2.1 防止零(ling)序CT誤差

（1）零序CT質(zhi)量(liang)要過硬；（2）實現嚴格校驗零序CT性能(neng)，5%及以上(shang)誤差率(lv)放棄；（3）10KV饋(kui)線(xian)零序保護動(dong)作(zuo)電(dian)流整定值和接地變壓器零序保護動(dong)作(zuo)電(dian)流整定值均(jun)應(ying)按一次(ci)值整定，保護校驗時(shi)應(ying)從零序CT一次(ci)升流檢(jian)驗其正確性。

2.2 確保電纜屏蔽層接地線(xian)一(yi)次成功率

（1）電(dian)(dian)纜(lan)(lan)屏(ping)(ping)蔽(bi)(bi)層(ceng)接地(di)線必(bi)須由上(shang)向下穿(chuan)(chuan)過零(ling)(ling)序CT，并與(yu)電(dian)(dian)纜(lan)(lan)支架絕(jue)緣，在穿(chuan)(chuan)過零(ling)(ling)序CT前不應有碰(peng)地(di)現象。電(dian)(dian)纜(lan)(lan)屏(ping)(ping)蔽(bi)(bi)層(ceng)接地(di)線頭、尾留(liu)出部(bu)分(fen)金屬導體，用于一次(ci)升(sheng)流，其余(yu)部(bu)分(fen)用絕(jue)緣材料可(ke)靠包扎。當電(dian)(dian)纜(lan)(lan)屏(ping)(ping)蔽(bi)(bi)層(ceng)接地(di)線引出點(dian)(dian)低于零(ling)(ling)序CT時(shi)，電(dian)(dian)纜(lan)(lan)屏(ping)(ping)蔽(bi)(bi)層(ceng)接地(di)線不能(neng)穿(chuan)(chuan)過零(ling)(ling)序CT。盡量(liang)避免電(dian)(dian)纜(lan)(lan)屏(ping)(ping)蔽(bi)(bi)層(ceng)接地(di)線引出點(dian)(dian)位于零(ling)(ling)序電(dian)(dian)流互感器的中間位置；（2）加強專業(ye)技能(neng)培訓，使各相關班(ban)組人員(yuan)清楚零(ling)(ling)序CT安(an)裝方法(fa)。特別是(shi)繼(ji)電(dian)(dian)保護專業(ye)和電(dian)(dian)纜(lan)(lan)專業(ye)的人員(yuan)，必(bi)須要掌握零(ling)(ling)序CT安(an)裝方法(fa)和電(dian)(dian)纜(lan)(lan)屏(ping)(ping)蔽(bi)(bi)層(ceng)接地(di)線安(an)裝方法(fa)，并嚴格執行；（3）加強驗收管(guan)理，繼(ji)保、運行、電(dian)(dian)纜(lan)(lan)等(deng)專業(ye)班(ban)組共同(tong)把好零(ling)(ling)序CT安(an)裝接線關。

2.3 消除饋線保(bao)護拒動隱患

（1）選用質量可(ke)靠，運行(xing)成熟、故障(zhang)率少的保(bao)護(hu)裝置；（2）對運行(xing)年限長和(he)經常故障(zhang)的保(bao)護(hu)裝置，要計劃更換(huan)；（3）加強保(bao)護(hu)裝置的運行(xing)維護(hu)，發(fa)現故障(zhang)馬上(shang)處理；（4）安裝空(kong)調和(he)通(tong)風系統，改善保(bao)護(hu)裝置運行(xing)環境，防止元件長期在高(gao)溫條件下(xia)運行(xing)。

2.4 消(xiao)除饋(kui)線開(kai)關拒動(dong)隱患(huan)

（1）配置質量可靠，運(yun)行成(cheng)熟、故障(zhang)率少的(de)(de)開(kai)關設備(bei)；（2）對運(yun)行年限長(chang)的(de)(de)開(kai)關設備(bei)和(he)經常(chang)故障(zhang)的(de)(de)開(kai)關設備(bei)，要(yao)計劃(hua)更換(huan)逐步淘汰舊(jiu)式開(kai)關柜(ju)，更換(huan)成(cheng)電動儲(chu)能型(xing)或(huo)彈簧儲(chu)能型(xing)的(de)(de)密(mi)封(feng)式開(kai)關柜(ju)；（3）加強開(kai)關控制回路的(de)(de)維護，發現故障(zhang)馬上處理；（4）對于跳閘線圈(quan)經常(chang)燒(shao)壞的(de)(de)問題，應采(cai)用(yong)性能優良的(de)(de)線圈(quan)。

2.5 杜絕饋線(xian)高阻接地

變(bian)電(dian)器往往會(hui)安裝零序保護接地報警(jing)系統，一旦發(fa)生饋(kui)線(xian)(xian)高(gao)祖接地，信號(hao)會(hui)發(fa)生，此(ci)時可(ke)沿(yan)著信號(hao)指示(shi)來進行排查。此(ci)外(wai)，加強對10KV饋(kui)線(xian)(xian)線(xian)(xian)路改造，盡量減少(shao)線(xian)(xian)路供(gong)電(dian)半徑，合理調節(jie)各相負荷(he)平(ping)均分布，以(yi)此(ci)減少(shao)正常運行的電(dian)容電(dian)流。

3、結語

近(jin)年來，在(zai)電力(li)系統中各地(di)區(qu)電網都基(ji)本(ben)加裝了(le)接(jie)(jie)地(di)變壓(ya)(ya)器(qi)及(ji)相關保護(hu)設備，以此達到改善(shan)電網結構和(he)提高電網安全穩(wen)定運行(xing)的目的，然(ran)而，在(zai)陸續發(fa)生的接(jie)(jie)地(di)變壓(ya)(ya)器(qi)保護(hu)誤(wu)動事(shi)故中，加強變電站(zhan)接(jie)(jie)地(di)變壓(ya)(ya)器(qi)保護(hu)誤(wu)動的措(cuo)施勢在(zai)必(bi)行(xing)。

參考文獻

[1]王勇.110kV變電站接地變壓器(qi)保(bao)護誤動原因的分析與解(jie)決(jue)措施[J].農村電氣化，2010，（09）.

篇8

關(guan)鍵詞(ci) 變壓器保護(hu)；雙重化(hua)配(pei)置(zhi)；保護(hu)配(pei)置(zhi)

中圖(tu)分(fen)類(lei)號TM310 文獻標識碼A 文章編號 1674-6708（2011）49-0167-02

1 保護配置

根據GB/14285-2006《繼電(dian)(dian)(dian)(dian)(dian)保(bao)(bao)護(hu)(hu)和(he)(he)安全(quan)自動(dong)裝置(zhi)(zhi)技術(shu)規(gui)程》的(de)(de)(de)要求，容(rong)量(liang)(liang)(liang)(liang)和(he)(he)電(dian)(dian)(dian)(dian)(dian)壓(ya)等級(ji)各不(bu)相同(tong)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)力變壓(ya)器(qi)(qi)(qi)(qi)(qi)(qi)配置(zhi)(zhi)不(bu)盡相同(tong)的(de)(de)(de)保(bao)(bao)護(hu)(hu)。#7、#8主(zhu)(zhu)(zhu)變壓(ya)器(qi)(qi)(qi)(qi)(qi)(qi)包(bao)括(kuo)差(cha)動(dong)整斷(duan)、穩態比率差(cha)動(dong)等全(quan)部電(dian)(dian)(dian)(dian)(dian)氣(qi)量(liang)(liang)(liang)(liang)主(zhu)(zhu)(zhu)保(bao)(bao)護(hu)(hu)，瓦(wa)斯(si)等非電(dian)(dian)(dian)(dian)(dian)氣(qi)量(liang)(liang)(liang)(liang)主(zhu)(zhu)(zhu)保(bao)(bao)護(hu)(hu)和(he)(he)其他(ta)常(chang)規(gui)電(dian)(dian)(dian)(dian)(dian)氣(qi)量(liang)(liang)(liang)(liang)保(bao)(bao)護(hu)(hu)，另外，還包(bao)括(kuo)主(zhu)(zhu)(zhu)變壓(ya)器(qi)(qi)(qi)(qi)(qi)(qi)220kV側(ce)(ce)、110kV側(ce)(ce)、10kV發電(dian)(dian)(dian)(dian)(dian)機(ji)側(ce)(ce)和(he)(he)6kV高廠變側(ce)(ce)的(de)(de)(de)零序(xu)方向過(guo)流、間隙(xi)零序(xu)過(guo)流、零序(xu)過(guo)壓(ya)、復合電(dian)(dian)(dian)(dian)(dian)壓(ya)閉鎖等后備保(bao)(bao)護(hu)(hu)及(ji)各類報警信號。在國家電(dian)(dian)(dian)(dian)(dian)力公司2000年9月的(de)(de)(de)《防止電(dian)(dian)(dian)(dian)(dian)力生產重(zhong)(zhong)(zhong)大事故的(de)(de)(de)二十五項重(zhong)(zhong)(zhong)點要求》中(zhong)(zhong)明確提出，220kV主(zhu)(zhu)(zhu)變壓(ya)器(qi)(qi)(qi)(qi)(qi)(qi)的(de)(de)(de)微機(ji)保(bao)(bao)護(hu)(hu)必(bi)須雙重(zhong)(zhong)(zhong)化(hua)。因此，熱電(dian)(dian)(dian)(dian)(dian)廠#7、#8主(zhu)(zhu)(zhu)變壓(ya)器(qi)(qi)(qi)(qi)(qi)(qi)保(bao)(bao)護(hu)(hu)裝置(zhi)(zhi)均采用(yong)雙重(zhong)(zhong)(zhong)化(hua)配置(zhi)(zhi)，包(bao)括(kuo)RCS-978E電(dian)(dian)(dian)(dian)(dian)氣(qi)量(liang)(liang)(liang)(liang)保(bao)(bao)護(hu)(hu)裝置(zhi)(zhi)和(he)(he)RCS-974非電(dian)(dian)(dian)(dian)(dian)氣(qi)量(liang)(liang)(liang)(liang)保(bao)(bao)護(hu)(hu)裝置(zhi)(zhi)。而#7、#8主(zhu)(zhu)(zhu)變壓(ya)器(qi)(qi)(qi)(qi)(qi)(qi)220kV側(ce)(ce)采用(yong)內(nei)橋型接(jie)線(xian)，GIS中(zhong)(zhong)的(de)(de)(de)斷(duan)路(lu)器(qi)(qi)(qi)(qi)(qi)(qi)分(fen)別具(ju)有兩組跳閘(zha)線(xian)圈，該(gai)兩套(tao)保(bao)(bao)護(hu)(hu)裝置(zhi)(zhi)分(fen)別動(dong)作于斷(duan)路(lu)器(qi)(qi)(qi)(qi)(qi)(qi)中(zhong)(zhong)的(de)(de)(de)一(yi)組跳閘(zha)線(xian)圈。#7、#8主(zhu)(zhu)(zhu)變壓(ya)器(qi)(qi)(qi)(qi)(qi)(qi)差(cha)動(dong)保(bao)(bao)護(hu)(hu)電(dian)(dian)(dian)(dian)(dian)流分(fen)別取(qu)自220kV斷(duan)路(lu)器(qi)(qi)(qi)(qi)(qi)(qi)側(ce)(ce)和(he)(he)橋聯(lian)側(ce)(ce)、110kV側(ce)(ce)、發電(dian)(dian)(dian)(dian)(dian)機(ji)10kV側(ce)(ce)、高廠變6kV側(ce)(ce)電(dian)(dian)(dian)(dian)(dian)流互感器(qi)(qi)(qi)(qi)(qi)(qi)的(de)(de)(de)專用(yong)次級(ji)線(xian)圈，具(ju)體接(jie)入(ru)方式如圖1所(suo)示。

雙重化的(de)保(bao)護采(cai)用同(tong)一廠(chang)家、相同(tong)原理和相同(tong)接線方式，對變壓器發生各類復(fu)雜故(gu)障時(shi)可靠切除故(gu)障和日常設備運(yun)行維護更加有利。

2 保護整定

2.1 差動(dong)速斷(duan)保護

整定原(yuan)則：按躲過勵(li)磁(ci)涌流(liu)，最嚴重外部(bu)故障時的(de)不平衡電流(liu)及互感器(qi)飽和，并保證在最小運行方(fang)式下(xia)最小短路電流(liu)有足夠靈敏度(du)整定。

2.2 啟動和報警值

差動(dong)啟動(dong)電(dian)流(liu)值：為防止運行中變(bian)壓(ya)器的(de)CT短線和涌流(liu)造成誤動(dong)，按(an)躲過變(bian)壓(ya)器額定負(fu)荷下的(de)不平衡電(dian)流(liu)整定：

TA報(bao)警差(cha)流定值：按躲過最大(da)負荷下由于CT誤(wu)差(cha)造成(cheng)的不平衡電流和(he)最大(da)分接頭誤(wu)差(cha)。

2.3 比率(lv)差(cha)動定值

穩(wen)態比(bi)率差動動作方程：

其(qi)中Ie為變壓(ya)器額定電流(liu)；

Im1.分(fen)別為變(bian)壓器各(ge)側電流(liu)；

Icdqd為穩態比率差動起(qi)動定值(zhi)；

Id為差動電流；

Ir為制動電流。

另外，變(bian)壓器(qi)220kV、110kV、發(fa)電機、高廠變(bian)各側后備保護(hu)均(jun)按(an)照裝置技術(shu)說明書進行整定。

3 結論

采用保護雙重化后，保護的(de)運行方式變(bian)得靈活(huo)，但由(you)于各類壓板較(jiao)多(duo)，操作變(bian)得復雜，與傳(chuan)統的(de)主(zhu)變(bian)保護有許多(duo)不同之處。

總而言之，石化電網(wang)#7、#8主(zhu)(zhu)變壓(ya)器采用保(bao)(bao)(bao)(bao)護(hu)(hu)雙重化后(hou)，增(zeng)加(jia)了(le)(le)保(bao)(bao)(bao)(bao)護(hu)(hu)裝(zhuang)置運行的(de)靈(ling)活性與(yu)可(ke)靠性，保(bao)(bao)(bao)(bao)護(hu)(hu)的(de)出(chu)(chu)現(xian)是一(yi)種(zhong)進步。 從微機變壓(ya)器保(bao)(bao)(bao)(bao)護(hu)(hu)發(fa)展趨勢(shi)看，微機變壓(ya)器保(bao)(bao)(bao)(bao)護(hu)(hu)選擇雙主(zhu)(zhu)雙后(hou)、主(zhu)(zhu)后(hou)一(yi)體的(de)配置，即保(bao)(bao)(bao)(bao)護(hu)(hu)功能由彼此獨立(li)的(de)不同(tong)CPU插件實(shi)現(xian)，出(chu)(chu)口(kou)跳閘回(hui)路分開，這種(zhong)結構和原則突(tu)出(chu)(chu)地體現(xian)了(le)(le)微機＝保(bao)(bao)(bao)(bao)護(hu)(hu)構成(cheng)的(de)特點及(ji)優越性，既多CPU并行處理，整體結構緊湊，數據共(gong)享，又組屏相對(dui)簡(jian)單、回(hui)路清晰、對(dui)外連(lian)線(xian)簡(jian)單，投(tou)退方便、獨立(li)性強(qiang)，是今后(hou)主(zhu)(zhu)變微機保(bao)(bao)(bao)(bao)護(hu)(hu)發(fa)展的(de)方向。

參考文獻

篇9

關(guan)鍵詞：變壓器，過(guo)電壓，保護措(cuo)施

 

變(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)器運行時，如果電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)超過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)它的(de)(de)(de)最大(da)允許工作(zuo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)，稱(cheng)(cheng)為(wei)(wei)變(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)器的(de)(de)(de)過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)。過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)往(wang)往(wang)對變(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)器的(de)(de)(de)絕(jue)緣(yuan)有很(hen)大(da)的(de)(de)(de)危害，甚至使(shi)絕(jue)緣(yuan)擊穿。過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)分(fen)(fen)為(wei)(wei)內(nei)部(bu)過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)和大(da)氣(qi)過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)兩種。輸(shu)電(dian)(dian)(dian)(dian)(dian)(dian)線(xian)路直接(jie)遭雷(lei)擊或(huo)雷(lei)云放電(dian)(dian)(dian)(dian)(dian)(dian)時，電(dian)(dian)(dian)(dian)(dian)(dian)磁場的(de)(de)(de)劇烈變(bian)化所引起(qi)的(de)(de)(de)過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)稱(cheng)(cheng)為(wei)(wei)大(da)氣(qi)過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)(外部(bu)過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya))；當變(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)器或(huo)線(xian)路上的(de)(de)(de)開關合閘或(huo)拉(la)閘時，因系統中電(dian)(dian)(dian)(dian)(dian)(dian)磁能量振(zhen)蕩(dang)和積(ji)聚而產生(sheng)的(de)(de)(de)過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)稱(cheng)(cheng)為(wei)(wei)內(nei)部(bu)過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)。變(bian)壓(ya)(ya)(ya)(ya)(ya)(ya)器的(de)(de)(de)這兩種過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)都是作(zuo)用時間短促的(de)(de)(de)瞬(shun)變(bian)過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)程。科技論文。內(nei)部(bu)過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)一般為(wei)(wei)額定電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)的(de)(de)(de)3.0－4.5倍，而大(da)氣(qi)過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)數值很(hen)高，可達額定電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)的(de)(de)(de)8－12倍，并(bing)且繞組(zu)中電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)分(fen)(fen)布極不均(jun)勻(yun)，端頭部(bu)分(fen)(fen)線(xian)匝受到的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)很(hen)高。因此，必須采取必要的(de)(de)(de)措施，防止過(guo)(guo)(guo)(guo)(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)(ya)的(de)(de)(de)發生(sheng)和進行有效的(de)(de)(de)保護。

過(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)在變(bian)(bian)壓(ya)(ya)器中(zhong)破壞絕(jue)緣(yuan)有兩種情況，一(yi)(yi)是將繞(rao)(rao)(rao)組(zu)與(yu)鐵心(或(huo)油箱)之間的(de)(de)(de)(de)絕(jue)緣(yuan)高壓(ya)(ya)繞(rao)(rao)(rao)組(zu)與(yu)低(di)壓(ya)(ya)繞(rao)(rao)(rao)組(zu)之間的(de)(de)(de)(de)絕(jue)緣(yuan)(這些(xie)絕(jue)緣(yuan)稱(cheng)為(wei)(wei)主絕(jue)緣(yuan))擊穿(chuan)(chuan)；另(ling)一(yi)(yi)種是在同(tong)一(yi)(yi)繞(rao)(rao)(rao)組(zu)內將匝(za)與(yu)匝(za)之間或(huo)一(yi)(yi)段(duan)繞(rao)(rao)(rao)組(zu)與(yu)另(ling)一(yi)(yi)段(duan)繞(rao)(rao)(rao)之間的(de)(de)(de)(de)絕(jue)緣(yuan)(這些(xie)絕(jue)緣(yuan)稱(cheng)為(wei)(wei)縱絕(jue)緣(yuan))擊穿(chuan)(chuan)。由(you)于過(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)時(shi)(shi)(shi)間極短，電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)從(cong)零上(shang)升到(dao)最(zui)大值再(zai)下降到(dao)零均在極短的(de)(de)(de)(de)時(shi)(shi)(shi)間內完(wan)成(cheng)，因而具有高頻(pin)(pin)振蕩的(de)(de)(de)(de)特性，其(qi)頻(pin)(pin)率(lv)可達100kHZ以上(shang)。在正常運(yun)行時(shi)(shi)(shi)，電(dian)(dian)(dian)(dian)(dian)網的(de)(de)(de)(de)頻(pin)(pin)率(lv)是50HZ，變(bian)(bian)壓(ya)(ya)器的(de)(de)(de)(de)容(rong)(rong)抗很(hen)大，而感擴ωL很(hen)小(xiao)，因此可以忽略電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)的(de)(de)(de)(de)影(ying)響，認為(wei)(wei)電(dian)(dian)(dian)(dian)(dian)流(liu)完(wan)全從(cong)繞(rao)(rao)(rao)組(zu)內部流(liu)過(guo)(guo)(guo)。但對高頻(pin)(pin)過(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)波(bo)來說(shuo)，變(bian)(bian)壓(ya)(ya)器的(de)(de)(de)(de)容(rong)(rong)抗變(bian)(bian)成(cheng)很(hen)小(xiao)，而感抗變(bian)(bian)成(cheng)很(hen)大，此時(shi)(shi)(shi)電(dian)(dian)(dian)(dian)(dian)流(liu)主要由(you)電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)流(liu)過(guo)(guo)(guo)，所以必(bi)須考(kao)慮(lv)(lv)電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)的(de)(de)(de)(de)影(ying)響。科技論文。考(kao)慮(lv)(lv)電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)影(ying)響后，變(bian)(bian)壓(ya)(ya)器的(de)(de)(de)(de)分(fen)布參數電(dian)(dian)(dian)(dian)(dian)路（見后面圖1）。

其中：CFe——繞(rao)(rao)組(zu)每(mei)(mei)單位(wei)(wei)(wei)(wei)長(chang)度上(shang)(shang)的對(dui)地電(dian)容；C’——高(gao)低壓繞(rao)(rao)組(zu)之間每(mei)(mei)單位(wei)(wei)(wei)(wei)長(chang)度上(shang)(shang)的電(dian)容；Ct——繞(rao)(rao)組(zu)每(mei)(mei)單位(wei)(wei)(wei)(wei)長(chang)度上(shang)(shang)的匝間電(dian)容；L’——過電(dian)壓時繞(rao)(rao)組(zu)每(mei)(mei)單位(wei)(wei)(wei)(wei)長(chang)度上(shang)(shang)的漏電(dian)感；R’——繞(rao)(rao)組(zu)每(mei)(mei)單位(wei)(wei)(wei)(wei)長(chang)度上(shang)(shang)的電(dian)阻(zu)。

下(xia)面簡單說(shuo)明兩種不(bu)同類型過(guo)電壓產生的原因：

1.內部過電(dian)(dian)壓(ya)我(wo)市電(dian)(dian)網中，絕大多數是降(jiang)壓(ya)變壓(ya)器(qi)(qi)，下面(mian)就以降(jiang)壓(ya)變壓(ya)器(qi)(qi)空載(zai)拉閘為例說明內部電(dian)(dian)壓(ya)產生的原因(yin)

根據(ju)變壓(ya)(ya)器(qi)(qi)(qi)參(can)數的(de)(de)(de)(de)(de)(de)(de)折算(suan)(suan)法(fa)可(ke)知，把二(er)次側(ce)(ce)(低壓(ya)(ya)側(ce)(ce))電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)折算(suan)(suan)到(dao)一(yi)次側(ce)(ce)(高壓(ya)(ya)側(ce)(ce))時(shi)(shi)(shi)(shi)(shi)，電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)折算(suan)(suan)值(zhi)(zhi)(zhi)為(wei)實際(ji)值(zhi)(zhi)(zhi)的(de)(de)(de)(de)(de)(de)(de)(1/K2)倍(bei)(bei)，所(suo)以(yi)二(er)次側(ce)(ce)電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)的(de)(de)(de)(de)(de)(de)(de)影(ying)響可(ke)以(yi)略(lve)去不(bu)計。這就(jiu)是(shi)說，空載(zai)時(shi)(shi)(shi)(shi)(shi)可(ke)以(yi)忽略(lve)二(er)次側(ce)(ce)的(de)(de)(de)(de)(de)(de)(de)影(ying)響。就(jiu)一(yi)次繞(rao)組(zu)來說，由(you)(you)于(yu)(yu)每(mei)單位長度(du)上(shang)的(de)(de)(de)(de)(de)(de)(de)對地電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)CFe是(shi)并聯的(de)(de)(de)(de)(de)(de)(de)，故(gu)對地總電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)為(wei)CFe=ΣCFe由(you)(you)于(yu)(yu)一(yi)次側(ce)(ce)單位長度(du)上(shang)的(de)(de)(de)(de)(de)(de)(de)匝間(jian)(jian)(jian)電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)Ct是(shi)串聯的(de)(de)(de)(de)(de)(de)(de)，故(gu)它的(de)(de)(de)(de)(de)(de)(de)匝間(jian)(jian)(jian)總電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)為(wei)Ct=1/(Σ1/Ct)在電(dian)(dian)(dian)(dian)(dian)力(li)變壓(ya)(ya)器(qi)(qi)(qi)中(zhong)，通常CFe＞＞Ct，所(suo)以(yi)定性分析(xi)時(shi)(shi)(shi)(shi)(shi)，匝間(jian)(jian)(jian)電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)的(de)(de)(de)(de)(de)(de)(de)影(ying)響也可(ke)略(lve)去不(bu)計。當再忽略(lve)繞(rao)組(zu)電(dian)(dian)(dian)(dian)(dian)阻R1時(shi)(shi)(shi)(shi)(shi)，可(ke)得空載(zai)拉(la)閘(zha)過電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)時(shi)(shi)(shi)(shi)(shi)的(de)(de)(de)(de)(de)(de)(de)簡化等效電(dian)(dian)(dian)(dian)(dian)路(lu)（見后面(mian)圖2）：其中(zhong)L1是(shi)一(yi)次繞(rao)組(zu)的(de)(de)(de)(de)(de)(de)(de)全(quan)自(zi)感。把空載(zai)變壓(ya)(ya)器(qi)(qi)(qi)從電(dian)(dian)(dian)(dian)(dian)網上(shang)拉(la)閘(zha)時(shi)(shi)(shi)(shi)(shi)，如果空載(zai)電(dian)(dian)(dian)(dian)(dian)流(liu)的(de)(de)(de)(de)(de)(de)(de)瞬時(shi)(shi)(shi)(shi)(shi)值(zhi)(zhi)(zhi)不(bu)等于(yu)(yu)零而是(shi)某(mou)一(yi)數值(zhi)(zhi)(zhi)Ia，這時(shi)(shi)(shi)(shi)(shi)相應(ying)的(de)(de)(de)(de)(de)(de)(de)外施電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)瞬時(shi)(shi)(shi)(shi)(shi)值(zhi)(zhi)(zhi)為(wei)Ua。于(yu)(yu)是(shi)在拉(la)閘(zha)瞬間(jian)(jian)(jian)，電(dian)(dian)(dian)(dian)(dian)感L1中(zhong)儲(chu)藏的(de)(de)(de)(de)(de)(de)(de)磁場能量(liang)(liang)為(wei)1/2L1i2a，電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)CFe上(shang)儲(chu)藏的(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)場能量(liang)(liang)為(wei)1/2CFeU2a。由(you)(you)于(yu)(yu)這時(shi)(shi)(shi)(shi)(shi)變壓(ya)(ya)器(qi)(qi)(qi)的(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)路(lu)是(shi)由(you)(you)電(dian)(dian)(dian)(dian)(dian)感L1和(he)電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)CFe并聯的(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)路(lu)，故(gu)在拉(la)閘(zha)瞬間(jian)(jian)(jian)，回路(lu)內將發生電(dian)(dian)(dian)(dian)(dian)磁振蕩過程(cheng)。在振蕩過程(cheng)中(zhong)，當某(mou)一(yi)瞬間(jian)(jian)(jian)電(dian)(dian)(dian)(dian)(dian)流(liu)等于(yu)(yu)零時(shi)(shi)(shi)(shi)(shi)，此時(shi)(shi)(shi)(shi)(shi)磁場能量(liang)(liang)全(quan)部轉化為(wei)電(dian)(dian)(dian)(dian)(dian)場能量(liang)(liang)，由(you)(you)電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)吸收，電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)上(shang)的(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)便升高到(dao)最(zui)大(da)值(zhi)(zhi)(zhi)Ucmax。當不(bu)考慮能量(liang)(liang)損失時(shi)(shi)(shi)(shi)(shi)，根據(ju)能量(liang)(liang)守恒原理有(you)CFeU2cmax= L1i2a＋CFeU2a故(gu)得上(shang)式表明，當拉(la)閘(zha)電(dian)(dian)(dian)(dian)(dian)流(liu)和(he)電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)上(shang)的(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)一(yi)定時(shi)(shi)(shi)(shi)(shi)，繞(rao)組(zu)的(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)感愈大(da)，對地電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)(rong)(rong)愈小，則(ze)拉(la)閘(zha)時(shi)(shi)(shi)(shi)(shi)過電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)愈高。電(dian)(dian)(dian)(dian)(dian)力(li)系統中(zhong)，拉(la)閘(zha)過電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)通常不(bu)超過額定電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)的(de)(de)(de)(de)(de)(de)(de)3.0－4.5倍(bei)(bei)。

2.大(da)氣(qi)過電(dian)壓(ya)大(da)氣(qi)過電(dian)壓(ya)是輸(shu)電(dian)線(xian)路直接(jie)遭受雷(lei)擊(ji)或雷(lei)云放電(dian)時，電(dian)磁場(chang)的(de)劇烈變(bian)化所引(yin)起的(de)

當輸(shu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)線(xian)(xian)(xian)路直接遭受雷(lei)(lei)(lei)擊(ji)(ji)(ji)時(shi)，雷(lei)(lei)(lei)云所(suo)帶的(de)(de)(de)(de)(de)(de)(de)(de)(de)大(da)(da)量電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)荷(he)(設(she)為(wei)正電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)荷(he))通過(guo)(guo)放電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)渠道落到(dao)(dao)(dao)輸(shu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)線(xian)(xian)(xian)上(shang)，大(da)(da)量的(de)(de)(de)(de)(de)(de)(de)(de)(de)自由(you)(you)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)荷(he)向(xiang)輸(shu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)線(xian)(xian)(xian)路的(de)(de)(de)(de)(de)(de)(de)(de)(de)兩端傳播，就在輸(shu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)線(xian)(xian)(xian)上(shang)引(yin)起沖擊(ji)(ji)(ji)過(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)波(bo)(bo)，稱(cheng)為(wei)雷(lei)(lei)(lei)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)波(bo)(bo)。雷(lei)(lei)(lei)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)波(bo)(bo)向(xiang)輸(shu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)線(xian)(xian)(xian)兩端傳播的(de)(de)(de)(de)(de)(de)(de)(de)(de)速度接近(jin)于(yu)(yu)光速，持續(xu)的(de)(de)(de)(de)(de)(de)(de)(de)(de)時(shi)間(jian)(jian)(jian)(jian)只(zhi)(zhi)有幾十(shi)微(wei)秒，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)由(you)(you)零(ling)上(shang)升到(dao)(dao)(dao)最(zui)(zui)大(da)(da)值的(de)(de)(de)(de)(de)(de)(de)(de)(de)時(shi)間(jian)(jian)(jian)(jian)只(zhi)(zhi)有幾微(wei)秒。雷(lei)(lei)(lei)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)波(bo)(bo)的(de)(de)(de)(de)(de)(de)(de)(de)(de)典型波(bo)(bo)形為(wei)曲線(xian)(xian)(xian)由(you)(you)零(ling)上(shang)升到(dao)(dao)(dao)最(zui)(zui)大(da)(da)值這一(yi)段稱(cheng)為(wei)波(bo)(bo)頭，下(xia)降部(bu)分稱(cheng)為(wei)波(bo)(bo)尾。如果把波(bo)(bo)頭所(suo)占時(shi)間(jian)(jian)(jian)(jian)看成(cheng)是周(zhou)期(qi)波(bo)(bo)的(de)(de)(de)(de)(de)(de)(de)(de)(de)四分之一(yi)周(zhou)期(qi)，則(ze)雷(lei)(lei)(lei)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)波(bo)(bo)可看成(cheng)是頻率極(ji)高(gao)(gao)(gao)(gao)的(de)(de)(de)(de)(de)(de)(de)(de)(de)周(zhou)期(qi)性波(bo)(bo)。這樣(yang)，當過(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)波(bo)(bo)到(dao)(dao)(dao)達(da)變(bian)壓(ya)(ya)器出線(xian)(xian)(xian)端時(shi)，相當于(yu)(yu)給變(bian)壓(ya)(ya)器加(jia)上(shang)了一(yi)個頻率極(ji)高(gao)(gao)(gao)(gao)的(de)(de)(de)(de)(de)(de)(de)(de)(de)高(gao)(gao)(gao)(gao)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)。這一(yi)瞬變(bian)過(guo)(guo)程(cheng)很(hen)(hen)快，一(yi)開始，由(you)(you)于(yu)(yu)高(gao)(gao)(gao)(gao)頻下(xia)，ωL很(hen)(hen)大(da)(da)的(de)(de)(de)(de)(de)(de)(de)(de)(de)，1/ωC很(hen)(hen)小(xiao)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)只(zhi)(zhi)從高(gao)(gao)(gao)(gao)壓(ya)(ya)繞(rao)(rao)組(zu)(zu)的(de)(de)(de)(de)(de)(de)(de)(de)(de)匝(za)(za)(za)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)和對(dui)地(di)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)中流(liu)(liu)(liu)(liu)過(guo)(guo)。由(you)(you)于(yu)(yu)低(di)壓(ya)(ya)繞(rao)(rao)組(zu)(zu)靠近(jin)鐵心，它的(de)(de)(de)(de)(de)(de)(de)(de)(de)對(dui)地(di)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)很(hen)(hen)大(da)(da)，(即容(rong)(rong)(rong)抗很(hen)(hen)小(xiao))，可近(jin)似(si)地(di)認為(wei)低(di)壓(ya)(ya)繞(rao)(rao)組(zu)(zu)接地(di)。科技(ji)論(lun)文。可雷(lei)(lei)(lei)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)波(bo)(bo)襲擊(ji)(ji)(ji)時(shi)，沿繞(rao)(rao)組(zu)(zu)高(gao)(gao)(gao)(gao)度上(shang)的(de)(de)(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)分布取決于(yu)(yu)匝(za)(za)(za)間(jian)(jian)(jian)(jian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)Ct和對(dui)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)CFe的(de)(de)(de)(de)(de)(de)(de)(de)(de)比例。在一(yi)般情況下(xia)，由(you)(you)于(yu)(yu)兩種電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)都(dou)存在，過(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)時(shi)，一(yi)部(bu)分電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)由(you)(you)對(dui)地(di)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)分流(liu)(liu)(liu)(liu)，故每個匝(za)(za)(za)間(jian)(jian)(jian)(jian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)流(liu)(liu)(liu)(liu)的(de)(de)(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)不(bu)相等，上(shang)面(mian)的(de)(de)(de)(de)(de)(de)(de)(de)(de)匝(za)(za)(za)間(jian)(jian)(jian)(jian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)(rong)流(liu)(liu)(liu)(liu)過(guo)(guo)的(de)(de)(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)最(zui)(zui)大(da)(da)愈(yu)往下(xia)面(mian)則(ze)愈(yu)小(xiao)，隨著電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)沿繞(rao)(rao)組(zu)(zu)高(gao)(gao)(gao)(gao)度的(de)(de)(de)(de)(de)(de)(de)(de)(de)分布變(bian)為(wei)不(bu)均勻(yun)，見(jian)下(xia)圖：(圖3是過(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)波(bo)(bo)加(jia)在變(bian)壓(ya)(ya)器兩端的(de)(de)(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya))從圖中可見(jian)，起始電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)分布很(hen)(hen)不(bu)均勻(yun)，靠近(jin)輸(shu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)線(xian)(xian)(xian)A端的(de)(de)(de)(de)(de)(de)(de)(de)(de)頭幾匝(za)(za)(za)間(jian)(jian)(jian)(jian)出現很(hen)(hen)大(da)(da)的(de)(de)(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)梯度，因此，在頭幾個線(xian)(xian)(xian)匝(za)(za)(za)里，匝(za)(za)(za)間(jian)(jian)(jian)(jian)絕緣和線(xian)(xian)(xian)餅之間(jian)(jian)(jian)(jian)的(de)(de)(de)(de)(de)(de)(de)(de)(de)絕緣都(dou)受到(dao)(dao)(dao)很(hen)(hen)大(da)(da)的(de)(de)(de)(de)(de)(de)(de)(de)(de)威脅，這時(shi)最(zui)(zui)高(gao)(gao)(gao)(gao)匝(za)(za)(za)間(jian)(jian)(jian)(jian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)可能(neng)高(gao)(gao)(gao)(gao)達(da)額定電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)的(de)(de)(de)(de)(de)(de)(de)(de)(de)50－200倍(bei)。

3.過電(dian)壓(ya)(ya)保護為了防止變壓(ya)(ya)器繞組(zu)絕緣在(zai)過電(dian)壓(ya)(ya)時(shi)被擊穿，必須采取適當的過電(dian)壓(ya)(ya)保護措施(shi)，目前主要采用(yong)下列措施(shi)

3.1避雷器保護

在變壓(ya)器的出線端裝設避雷器，當雷電波從(cong)輸電線侵入(ru)時，避雷器的保護(hu)間隙被(bei)擊穿，過電壓(ya)波對地放電，這樣雷電波就(jiu)不會侵入(ru)變壓(ya)器，從(cong)而保護(hu)了(le)變壓(ya)器。

3.2加強絕緣

除了加強變壓器(qi)高(gao)壓繞組對(dui)地絕緣(yuan)外，針對(dui)雷電(dian)波作用(yong)的(de)(de)(de)特性，還要加強首端及(ji)末端部分(fen)線(xian)匝(za)的(de)(de)(de)絕緣(yuan)，以承受由于(yu)起(qi)始電(dian)壓分(fen)布不(bu)均勻而出現的(de)(de)(de)較高(gao)的(de)(de)(de)匝(za)間電(dian)壓。這種方法效(xiao)果有限，而且加厚絕緣(yuan)使散熱(re)困難(nan)，同時(shi)減(jian)少了匝(za)間電(dian)容(rong)，增大了匝(za)間電(dian)壓梯度(du)。目前只在35kV及(ji)以下的(de)(de)(de)變壓器(qi)中采用(yong)。

3.3增大匝(za)間電容

匝間(jian)(jian)電(dian)(dian)(dian)(dian)容相(xiang)對(dui)于對(dui)地電(dian)(dian)(dian)(dian)容愈(yu)大時，則電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)的(de)(de)(de)起始分布愈(yu)均勻，電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)梯度越小(xiao)，因此增(zeng)加(jia)匝間(jian)(jian)電(dian)(dian)(dian)(dian)容是(shi)有效的(de)(de)(de)過電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)保(bao)護措(cuo)施(shi)。過去常采用(yong)加(jia)裝靜電(dian)(dian)(dian)(dian)板或靜電(dian)(dian)(dian)(dian)屏(ping)的(de)(de)(de)方法，現在(zai)在(zai)110kV以上的(de)(de)(de)高(gao)壓(ya)(ya)(ya)(ya)變(bian)壓(ya)(ya)(ya)(ya)器上，廣泛采用(yong)糾(jiu)結式線圈。糾(jiu)結式線圈制造工藝簡單(dan)，不增(zeng)加(jia)材料，與連續式線圈相(xiang)比能顯著增(zeng)大匝間(jian)(jian)電(dian)(dian)(dian)(dian)容，所以現在(zai)高(gao)壓(ya)(ya)(ya)(ya)大型(xing)電(dian)(dian)(dian)(dian)力(li)變(bian)壓(ya)(ya)(ya)(ya)器的(de)(de)(de)高(gao)壓(ya)(ya)(ya)(ya)繞組大多數采用(yong)了這種(zhong)繞線法。結束(shu)語造成(cheng)變(bian)壓(ya)(ya)(ya)(ya)器過電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)的(de)(de)(de)原因多種(zhong)多樣(yang)，針對(dui)不同(tong)的(de)(de)(de)過電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)，有不同(tong)的(de)(de)(de)過電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)保(bao)護措(cuo)施(shi)。在(zai)實際工作中，我們應進行經濟上和技術上的(de)(de)(de)全面研究，選擇有效的(de)(de)(de)過電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)保(bao)護措(cuo)施(shi)，確保(bao)變(bian)壓(ya)(ya)(ya)(ya)器的(de)(de)(de)安全穩(wen)定運行。

篇10

關鍵(jian)詞：城(cheng)市(shi)地(di)鐵；供(gong)電系統(tong)；變壓器故障

中圖分類號：U231文獻標識碼： A

地鐵是(shi)靠(kao)電(dian)(dian)力牽引的(de)(de)(de)電(dian)(dian)動列車，地鐵上(shang)的(de)(de)(de)一些輔助設(she)施(shi)如照(zhao)明、空(kong)調、通(tong)風、排水、通(tong)信、自動扶梯和防災報替等，都依靠(kao)電(dian)(dian)能才(cai)能運行，而(er)電(dian)(dian)能是(shi)靠(kao)供(gong)電(dian)(dian)系統(tong)提(ti)供(gong)的(de)(de)(de)，電(dian)(dian)力系統(tong)中(zhong)的(de)(de)(de)重要電(dian)(dian)氣設(she)備就是(shi)變(bian)壓(ya)器，一旦(dan)發(fa)生故障(zhang)后果將不堪設(she)想。因此，本課題(ti)通(tong)過對地鐵供(gong)電(dian)(dian)系統(tong)變(bian)壓(ya)器故障(zhang)分析(xi)和研(yan)究，找(zhao)出其(qi)中(zhong)的(de)(de)(de)薄弱環(huan)節，摸索總結出系統(tong)中(zhong)一定的(de)(de)(de)故障(zhang)規(gui)律，以便指導(dao)地鐵的(de)(de)(de)日常維(wei)護來確(que)保地鐵安全可靠(kao)地運行。

1 地(di)鐵電(dian)力系統主(zhu)要能(neng)源

1.1 高壓供電

1.3 混合(he)供電方式

即集中(zhong)式(shi)(shi)和分散式(shi)(shi)兩者(zhe)結(jie)合(he)的(de)供電(dian)(dian)方(fang)式(shi)(shi)，其中(zhong)以(yi)集中(zhong)式(shi)(shi)供電(dian)(dian)方(fang)式(shi)(shi)為主，分散供電(dian)(dian)方(fang)式(shi)(shi)為輔，兩者(zhe)的(de)完(wan)美結(jie)合(he)使供電(dian)(dian)系統更加完(wan)善、更加可(ke)靠。

1.4 地鐵內(nei)部(bu)供電(dian)

地(di)(di)鐵內部供(gong)電(dian)是由(you)牽引和動(dong)力照(zhao)明的(de)(de)供(gong)電(dian)系統組成，首先將牽引變電(dian)所產生的(de)(de)三相(xiang)高壓交流電(dian)轉換(huan)成適(shi)合(he)實(shi)際需(xu)(xu)要(yao)的(de)(de)低壓直(zhi)流電(dian)，然后再經過(guo)饋電(dian)線(xian)送到接觸網上，最后就可以供(gong)地(di)(di)鐵車輛使用。像車站和區間的(de)(de)各類照(zhao)明、風機、扶梯、信(xin)號(hao)等自動(dong)化設(she)備都需(xu)(xu)要(yao)依賴此方式供(gong)電(dian)才能運行。

2 變壓器故障分(fen)析(xi)與保護

2.1 故障類型

內部故(gu)障：包(bao)含相(xiang)(xiang)間(jian)、單相(xiang)(xiang)接(jie)地和(he)繞組(zu)匝間(jian)三種(zhong)短路(lu)方式(shi)。這些故(gu)障帶(dai)來的危害非常大，發生故(gu)障產生的高溫電(dian)弧(hu)很容(rong)易(yi)燒毀鐵芯，而且使變壓(ya)器的油絕(jue)緣因受熱分解生成大量的氣體(ti)，從而引發油箱爆炸。

2.2 變壓器保護

為避免這些故障的(de)發生就需要對變壓器進行保(bao)護，具(ju)體實施方法如(ru)下：

（1）瓦斯保(bao)護：適用于(yu)高于(yu)0.8MVA油(you)(you)浸式變壓(ya)(ya)器和(he)高于(yu)0.4MVA戶內變壓(ya)(ya)器保(bao)護，瓦斯保(bao)護可(ke)防止繞組的(de)相間短路和(he)匝間短路故障的(de)發生，變壓(ya)(ya)器油(you)(you)絕緣因(yin)受熱分解產生大量氣(qi)體(ti)從(cong)油(you)(you)箱經連(lian)通(tong)管(guan)流(liu)向油(you)(you)枕(zhen)，通(tong)過反應(ying)變壓(ya)(ya)器油(you)(you)箱內部氣(qi)體(ti)的(de)數(shu)量和(he)流(liu)動的(de)速(su)度構成瓦斯保(bao)護。

（2）縱差保(bao)護(hu)或電流速斷(duan)(duan)保(bao)護(hu)：此方法(fa)可(ke)避免變(bian)壓器繞(rao)組和(he)引出線的(de)(de)相間(jian)(jian)短路(lu)、中性點直接接地電網側繞(rao)組短路(lu)、引線接地短路(lu)以及(ji)繞(rao)組匝間(jian)(jian)短路(lu)問(wen)題。裝設差動保(bao)護(hu)適用于并列運行(xing)變(bian)壓器（6.3MVA以上(shang)）和(he)單獨運行(xing)的(de)(de)變(bian)壓器（含10MVA及(ji)10MVA以上(shang)）也適用于6.3MVA及(ji)以上(shang)的(de)(de)廠用變(bian)壓器，而對于變(bian)壓器（10MVA以下(xia)）過流大于0.5時則采用電流速斷(duan)(duan)進行(xing)保(bao)護(hu)。

（3）安(an)裝過電(dian)(dian)流(liu)(liu)保(bao)(bao)(bao)(bao)護可(ke)以(yi)把因相間(jian)短路所造成的(de)過電(dian)(dian)流(liu)(liu)等問(wen)題進行有效地解決，還(huan)可(ke)以(yi)當成縱差(cha)保(bao)(bao)(bao)(bao)護及瓦斯(si)的(de)后(hou)備(bei)(bei)保(bao)(bao)(bao)(bao)護措(cuo)施(shi)。一般為變壓器選取在反應相間(jian)上短路電(dian)(dian)流(liu)(liu)加強(qiang)時(shi)(shi)會做出動(dong)(dong)作(zuo)的(de)那種電(dian)(dian)流(liu)(liu)保(bao)(bao)(bao)(bao)護當作(zuo)后(hou)備(bei)(bei)保(bao)(bao)(bao)(bao)護措(cuo)施(shi)。同時(shi)(shi)如果安(an)裝阻抗保(bao)(bao)(bao)(bao)護、復合電(dian)(dian)壓在啟動(dong)(dong)時(shi)(shi)過電(dian)(dian)流(liu)(liu)保(bao)(bao)(bao)(bao)護、過電(dian)(dian)流(liu)(liu)保(bao)(bao)(bao)(bao)護、負序(xu)時(shi)(shi)過電(dian)(dian)流(liu)(liu)保(bao)(bao)(bao)(bao)護與(yu)低(di)壓啟動(dong)(dong)時(shi)(shi)過電(dian)(dian)流(liu)(liu)保(bao)(bao)(bao)(bao)護可(ke)較好(hao)達(da)到其對靈敏(min)度的(de)需求。

（4）對大(da)于110kV的中(zhong)性(xing)(xing)點(dian)直接(jie)接(jie)地系(xi)統(tong)中(zhong)的變壓(ya)(ya)器，應裝設零(ling)序電流對其(qi)進行保(bao)護。在裝設過程(cheng)中(zhong)要注意(yi)其(qi)電流的大(da)小(xiao)和系(xi)統(tong)中(zhong)變壓(ya)(ya)器中(zhong)性(xing)(xing)點(dian)接(jie)地臺數(shu)和位置關系(xi)，從而有效避免大(da)接(jie)地電流系(xi)統(tong)中(zhong)單項(xiang)和兩(liang)相(xiang)接(jie)地所發生的短路(lu)現(xian)象。

（5）裝(zhuang)設過勵磁保(bao)護(hu)：勵磁涌(yong)流對變壓(ya)器(qi)(qi)的(de)(de)危害性不大，這種沖(chong)擊電流發(fa)生的(de)(de)時間(jian)相(xiang)當(dang)短暫，帶(dai)(dai)來的(de)(de)影響可(ke)(ke)忽(hu)略不計，但對變壓(ya)器(qi)(qi)進(jin)行(xing)多次連續(xu)合閘充電所帶(dai)(dai)來的(de)(de)大電流沖(chong)擊對繞組間(jian)的(de)(de)機械力作用會帶(dai)(dai)來影響，一般會造成(cheng)該固定物松(song)動。同時，勵磁通流還能引起變壓(ya)器(qi)(qi)的(de)(de)差動保(bao)護(hu)，其發(fa)生的(de)(de)故(gu)障(zhang)(zhang)(zhang)(zhang)類型較多，按照回路進(jin)行(xing)劃分可(ke)(ke)分為電路故(gu)障(zhang)(zhang)(zhang)(zhang)、油(you)路故(gu)障(zhang)(zhang)(zhang)(zhang)和(he)磁路故(gu)障(zhang)(zhang)(zhang)(zhang)。以變壓(ya)器(qi)(qi)所構成(cheng)主體結構為基礎，可(ke)(ke)將故(gu)障(zhang)(zhang)(zhang)(zhang)劃分成(cheng)鐵(tie)芯、繞組、附件及油(you)質四(si)種故(gu)障(zhang)(zhang)(zhang)(zhang)形式(shi)。

3地鐵供電系(xi)統中變壓(ya)器(qi)的保(bao)護(hu)

3.1電流(liu)速斷保護(hu)與縱聯差動保護(hu)

我們通(tong)過對變壓(ya)器(qi)(qi)安(an)裝(zhuang)電流速(su)斷(duan)保護(hu)(hu)或者(zhe)縱(zong)(zong)聯(lian)差(cha)(cha)動(dong)(dong)保護(hu)(hu)，來解(jie)決(jue)變壓(ya)器(qi)(qi)中性點直(zhi)接接地電網側繞組(zu)和引線(xian)接地短(duan)路(lu)、引出線(xian)和繞組(zu)造成的(de)(de)相(xiang)間(jian)短(duan)路(lu)以(yi)及繞組(zu)匝間(jian)短(duan)路(lu)等故障(zhang)。一(yi)般來說，電流速(su)斷(duan)保護(hu)(hu)應安(an)裝(zhuang)在(zai)過流時(shi)限大于(yu)0.5s的(de)(de)10MVA以(yi)下(xia)變壓(ya)器(qi)(qi)；縱(zong)(zong)聯(lian)差(cha)(cha)動(dong)(dong)保護(hu)(hu)應安(an)裝(zhuang)在(zai)10MVA及以(yi)上單獨(du)運行的(de)(de)變壓(ya)器(qi)(qi)和6.3MVA以(yi)上并列運行的(de)(de)變壓(ya)器(qi)(qi)。縱(zong)(zong)聯(lian)差(cha)(cha)動(dong)(dong)保護(hu)(hu)包括在(zai)暫態(tai)(tai)情況下(xia)、穩態(tai)(tai)情況下(xia)、帶制動(dong)(dong)特性的(de)(de)差(cha)(cha)動(dong)(dong)保護(hu)(hu)。縱(zong)(zong)聯(lian)差(cha)(cha)動(dong)(dong)保護(hu)(hu)反應被保護(hu)(hu)變壓(ya)器(qi)(qi)流出電流和隔斷(duan)流入(ru)的(de)(de)相(xiang)量差(cha)(cha)。

3.2瓦斯保護

變(bian)(bian)壓(ya)器(qi)保(bao)(bao)護(hu)(hu)中的(de)(de)(de)瓦(wa)斯(si)保(bao)(bao)護(hu)(hu)是(shi)指改變(bian)(bian)變(bian)(bian)壓(ya)器(qi)油(you)箱(xiang)內部氣體的(de)(de)(de)流動速(su)度和(he)數量(liang)對變(bian)(bian)壓(ya)器(qi)進行保(bao)(bao)護(hu)(hu)，防止變(bian)(bian)壓(ya)器(qi)出現各種(zhong)故(gu)障。我們需要對戶(hu)內的(de)(de)(de)0.4MVA以(yi)上(shang)變(bian)(bian)壓(ya)器(qi)和(he)戶(hu)外(wai)(wai)0.8MVA及以(yi)上(shang)的(de)(de)(de)油(you)浸式變(bian)(bian)壓(ya)器(qi)安裝瓦(wa)斯(si)保(bao)(bao)護(hu)(hu)裝置，從而解(jie)決(jue)變(bian)(bian)壓(ya)器(qi)油(you)箱(xiang)內部各種(zhong)油(you)面降低和(he)短路(lu)故(gu)障等問題。瓦(wa)斯(si)保(bao)(bao)護(hu)(hu)的(de)(de)(de)優(you)點主要有(you)靈敏度高、動作迅(xun)速(su)、接線安裝簡(jian)單，可以(yi)直接反映變(bian)(bian)壓(ya)器(qi)油(you)箱(xiang)內部發生的(de)(de)(de)各種(zhong)故(gu)障。不能直接反映油(you)箱(xiang)以(yi)外(wai)(wai)的(de)(de)(de)引出線及套(tao)管等部位上(shang)發生的(de)(de)(de)故(gu)障是(shi)瓦(wa)斯(si)保(bao)(bao)護(hu)(hu)最主要的(de)(de)(de)缺(que)點。因此，作為變(bian)(bian)壓(ya)器(qi)的(de)(de)(de)主要保(bao)(bao)護(hu)(hu)措(cuo)施(shi)之一的(de)(de)(de)瓦(wa)斯(si)保(bao)(bao)護(hu)(hu)，與(yu)縱聯差動保(bao)(bao)護(hu)(hu)相(xiang)互補(bu)充、相(xiang)互配合，及時有(you)效地解(jie)決(jue)變(bian)(bian)壓(ya)器(qi)的(de)(de)(de)各種(zhong)故(gu)障問題。

3.3過電流保護

變(bian)壓器保(bao)(bao)護(hu)(hu)中的(de)(de)(de)過(guo)(guo)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)保(bao)(bao)護(hu)(hu)主要作為(wei)縱聯差動、瓦斯保(bao)(bao)護(hu)(hu)的(de)(de)(de)后(hou)備(bei)保(bao)(bao)護(hu)(hu)措施，一般安裝(zhuang)(zhuang)在(zai)反應(ying)外部相(xiang)間短路引起的(de)(de)(de)過(guo)(guo)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)問題(ti)。為(wei)滿足(zu)靈敏度要求，可安裝(zhuang)(zhuang)低(di)壓啟動的(de)(de)(de)過(guo)(guo)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)保(bao)(bao)護(hu)(hu)、復合電(dian)(dian)(dian)(dian)壓啟動的(de)(de)(de)過(guo)(guo)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)保(bao)(bao)護(hu)(hu)、過(guo)(guo)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)保(bao)(bao)護(hu)(hu)、負序過(guo)(guo)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)保(bao)(bao)護(hu)(hu)以及阻抗保(bao)(bao)護(hu)(hu)，選用較大的(de)(de)(de)反應(ying)相(xiang)間短路電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)而(er)造成的(de)(de)(de)過(guo)(guo)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)保(bao)(bao)護(hu)(hu)作為(wei)變(bian)壓器的(de)(de)(de)后(hou)備(bei)保(bao)(bao)護(hu)(hu)措施。

3.4過勵磁保護

在變(bian)壓(ya)器(qi)保(bao)護中(zhong)安裝(zhuang)過(guo)勵磁保(bao)護是(shi)為了(le)解決變(bian)壓(ya)器(qi)中(zhong)的(de)過(guo)勵磁問題(ti)。由(you)于(yu)勵磁涌流(liu)造成的(de)沖(chong)擊(ji)電(dian)流(liu)存在的(de)時(shi)間很短，因(yin)(yin)此(ci)其對(dui)變(bian)壓(ya)器(qi)傷害不大，此(ci)外，勵磁涌流(liu)有(you)可(ke)能(neng)引起變(bian)壓(ya)器(qi)的(de)縱聯差動(dong)保(bao)護動(dong)作(zuo)。顯而易見(jian)，我們不宜多(duo)次(ci)連續(xu)合閘(zha)來對(dui)變(bian)壓(ya)器(qi)進行充電(dian)，因(yin)(yin)為繞組間的(de)機械力作(zuo)用會因(yin)(yin)為大電(dian)流(liu)的(de)多(duo)次(ci)沖(chong)擊(ji)而逐漸造成其固(gu)定(ding)物松(song)動(dong)，引起故障。

4 變(bian)壓(ya)器故障解(jie)決方法

（1）對三相(xiang)電(dian)壓(ya)進行定(ding)期(qi)檢查(cha)，如發現電(dian)壓(ya)嚴重失衡，要(yao)立(li)刻采(cai)取(qu)正(zheng)確措施對其進行調整，還要(yao)對變壓(ya)器的油位、油色(se)和溫度及時檢查(cha)，以防(fang)止滲漏。呼(hu)吸器里干燥劑(ji)一旦發生顏色(se)變化(hua)要(yao)立(li)刻更換(huan)。

（2）采取正確的(de)防(fang)污措施(shi)對(dui)(dui)配電(dian)變(bian)壓器進行保(bao)護(hu)，安(an)裝配套的(de)套管防(fang)污帽和(he)及時清理變(bian)壓器污垢，檢查管道是否有閃絡放(fang)電(dian)現象(xiang)。避免斷線、脫焊(han)和(he)斷裂(lie)的(de)情(qing)況(kuang)發生，還要對(dui)(dui)接地電(dian)阻進行定期遙測。

（3）配(pei)電(dian)(dian)變壓器在拆除過(guo)程(cheng)中(zhong)有(you)螺(luo)桿發生轉動(dong)的情況(kuang)，需嚴格處理，在確保(bao)無誤的情況(kuang)下才可投運。取用銅鋁(lv)過(guo)渡(du)線夾二(er)次(ci)導線的接線方(fang)式一定要合理選(xuan)擇，用導電(dian)(dian)膏涂(tu)抹(mo)于接觸面，使(shi)接觸面積增大，導電(dian)(dian)能力增強，減少發熱引起氧化(hua)。

（4）配(pei)電變(bian)壓器(qi)(qi)初步側裝(zhuang)避雷(lei)針，一定(ding)要(yao)選擇合格的避雷(lei)器(qi)(qi)，并定(ding)期對避雷(lei)器(qi)(qi)的預(yu)防(fang)性進(jin)行試驗，減少(shao)雷(lei)擊諧(xie)振(zhen)給變(bian)壓器(qi)(qi)帶來(lai)過電壓的現象(xiang)，對電感設備(bei)配(pei)備(bei)相對多的變(bian)壓器(qi)(qi)（100kVA以上）其上層油溫控制(zhi)在(zai)85℃以下(xia)。

（5）損壞(huai)變(bian)壓(ya)器的(de)原因(yin)(yin)(yin)很多(duo)，二次短(duan)(duan)路的(de)發生是(shi)(shi)其損壞(huai)的(de)直接因(yin)(yin)(yin)素。因(yin)(yin)(yin)此(ci)，對(dui)配(pei)電(dian)變(bian)壓(ya)器的(de)熔絲選擇很關鍵，其額定電(dian)流應(ying)在1.2～1.5之間，即便是(shi)(shi)因(yin)(yin)(yin)低(di)壓(ya)而產(chan)生短(duan)(duan)路，熔絲對(dui)變(bian)壓(ya)器起到關鍵保護作(zuo)用。

（6）當變壓器(qi)的(de)(de)三(san)相負載電(dian)(dian)流、電(dian)(dian)壓都不平衡時，應視為最大電(dian)(dian)流的(de)(de)負荷(he)。若(ruo)高于額定電(dian)(dian)流25%時，要(yao)將(jiang)負荷(he)進行三(san)相間的(de)(de)重(zhong)新(xin)分(fen)配。

5 結語

綜上(shang)所述，只要定(ding)期對設備(bei)進行巡視檢查，嚴(yan)格遵(zun)守規章制度來(lai)辦事，做好本(ben)職以內的(de)工作，熟練掌握地鐵變壓器(qi)故(gu)障(zhang)(zhang)產生的(de)諸多原(yuan)因，做到日(ri)常維護、人人保護的(de)原(yuan)則，就可以減少或避免變壓器(qi)故(gu)障(zhang)(zhang)的(de)產生，從而(er)對地鐵安全可靠(kao)的(de)運營提供(gong)保障(zhang)(zhang)。

參考文獻

[1] 何首賢，葛廷友(you)，姜秀玲.供配(pei)電技術[M].北京：水利電力出版社，2005.

[2] 劉娜(na)，梁(liang)國棟，王(wang)劉芳，等.電力(li)變壓器故障模式的(de)分析(xi)及(ji)危害(hai)評估[J].高(gao)電壓技(ji)術(shu)，2003.