驅動電源設計范文

時間:2023-03-29 09:55:12

導語(yu):如何才(cai)能(neng)寫好(hao)一篇(pian)驅動電源設(she)計,這就需要搜集整(zheng)理(li)更多的(de)(de)資料和文獻(xian),歡(huan)迎閱讀由公務員之(zhi)家整(zheng)理(li)的(de)(de)十篇(pian)范(fan)文,供你借鑒。

驅動電源設計

篇1

1)實際導通時柵極偏壓一般選12~15V為宜;而柵極負偏置電壓可使IGBT可靠關斷,一般負偏置電壓選-5V為宜。在實際應用中為防止柵極驅動電路出現高壓(ya)尖峰,最好(hao)在柵(zha)射之間(jian)并接兩(liang)只反向(xiang)串聯的穩壓(ya)二極管。

2)考(kao)慮到開(kai)通(tong)期間內部MOSFET產(chan)生Mill-er效(xiao)應,要用大電(dian)流驅動源對柵極的輸(shu)入電(dian)容(rong)進(jin)行(xing)快(kuai)速(su)(su)充放電(dian),以保(bao)證驅動信號(hao)有足(zu)夠陡(dou)峭(qiao)的上升(sheng)、下降沿,加(jia)快(kuai)開(kai)關速(su)(su)度(du),從而使IGBT的開(kai)關損耗盡量小(xiao)。

3)選擇合適的柵極串聯電阻(一般為10Ω左右)和合適的柵射并聯電阻(一般為數百歐姆),以保證動態驅動效果和防靜電效果。根據以上要求,可設計出如圖1所示的半橋LC串聯諧振充電電源的(de)IGBT驅(qu)動(dong)電(dian)(dian)路(lu)原(yuan)理圖。考慮到多數(shu)芯片難以承受20V及以上的(de)電(dian)(dian)源電(dian)(dian)壓(ya),所以驅(qu)動(dong)電(dian)(dian)源Vo采用18V。二(er)極(ji)管(guan)V79將(jiang)其(qi)(qi)(qi)拆分為(wei)(wei)+12.9V和-5.1V,前(qian)者是維持IGBT導通的(de)電(dian)(dian)壓(ya),后者用于IGBT關(guan)(guan)斷的(de)負(fu)電(dian)(dian)壓(ya)保護。光(guang)耦TLP350將(jiang)PWM弱電(dian)(dian)信號傳輸(shu)給驅(qu)動(dong)電(dian)(dian)路(lu)且實現了電(dian)(dian)氣隔離,而驅(qu)動(dong)器TC4422A可為(wei)(wei)IGBT模塊提供較高開(kai)(kai)關(guan)(guan)頻率下(xia)的(de)動(dong)態大電(dian)(dian)流開(kai)(kai)關(guan)(guan)信號,其(qi)(qi)(qi)輸(shu)出(chu)端口串聯(lian)(lian)(lian)的(de)電(dian)(dian)容C65可以進一步加快開(kai)(kai)關(guan)(guan)速度(du)。應(ying)注(zhu)意一個(ge)IGBT模塊有兩(liang)個(ge)相(xiang)同單管(guan),所以實際需要兩(liang)路(lu)不(bu)共地的(de)18V穩壓(ya)電(dian)(dian)源;另外IGBT柵(zha)射極(ji)之間(jian)的(de)510Ω并聯(lian)(lian)(lian)電(dian)(dian)阻應(ying)該直接(jie)焊裝在(zai)(zai)其(qi)(qi)(qi)管(guan)腳上(未(wei)在(zai)(zai)圖中畫出(chu)),而且最(zui)好在(zai)(zai)管(guan)腳上并聯(lian)(lian)(lian)焊裝一個(ge)1N4733和1N4744(反向(xiang)串聯(lian)(lian)(lian))穩壓(ya)二(er)極(ji)管(guan),以保護IGBT的(de)柵(zha)極(ji)。

2實驗結果及分析

在變換器的LC輸出端接入兩個2W/200Ω的電阻進行靜態測試。實驗中使用的儀器為:Agi-lent54833A型示波器,10073D低壓探頭。示波器置于AC檔對輸出電壓紋波進行觀測,波形如圖5所示。由實驗結果看,輸出紋波可以基本保持在±10mV以內,滿足設計要(yao)求(qiu)。此后對(dui)反(fan)激變換(huan)器(qi)電路板與IGBT模塊驅(qu)動(dong)電路板進行對(dui)接(jie)聯調(diao)。觀察(cha)了IGBT柵極的(de)(de)驅(qu)動(dong)信號波(bo)形。由(you)實驗結(jie)果看,IGBT在開通(tong)時驅(qu)動(dong)電壓(ya)(ya)接(jie)近13V,而在其關斷時間內(nei)電壓(ya)(ya)接(jie)近5V。這主要(yao)是(shi)電路中的(de)(de)光耦和大(da)電流驅(qu)動(dong)器(qi)本身(shen)內(nei)部的(de)(de)晶體管對(dui)驅(qu)動(dong)電壓(ya)(ya)有(you)所(suo)消耗(即管壓(ya)(ya)降)造成的(de)(de),故不可(ke)能完全達到18V供電電源的(de)(de)水平。

3結論

篇2

關鍵詞(ci):TFT液晶顯示;驅動電路;電源優(you)化設計

中圖(tu)分類(lei)號:TN873 文(wen)獻(xian)標識碼:A

一、前言

自從信息技(ji)術(shu)在(zai)人們(men)生(sheng)活(huo)中(zhong)出現(xian),并(bing)且得到(dao)了(le)越來越多人們(men)的(de)(de)(de)(de)青睞和應(ying)用(yong),利用(yong)電(dian)子設(she)備進行(xing)顯(xian)(xian)示(shi)(shi)的(de)(de)(de)(de)技(ji)術(shu)便(bian)得到(dao)了(le)長足的(de)(de)(de)(de)發(fa)(fa)(fa)展(zhan)(zhan),并(bing)且在(zai)人們(men)的(de)(de)(de)(de)生(sheng)活(huo)中(zhong)起到(dao)了(le)不可缺(que)少(shao)的(de)(de)(de)(de)作用(yong)。液(ye)晶(jing)顯(xian)(xian)示(shi)(shi)技(ji)術(shu),即是信息技(ji)術(shu)在(zai)人們(men)生(sheng)活(huo)中(zhong)的(de)(de)(de)(de)一個(ge)重要的(de)(de)(de)(de)應(ying)用(yong)領域。近幾年來,隨著液(ye)晶(jing)顯(xian)(xian)示(shi)(shi)技(ji)術(shu)的(de)(de)(de)(de)發(fa)(fa)(fa)展(zhan)(zhan),薄膜(mo)晶(jing)體(ti)管(guan)(guan)的(de)(de)(de)(de)出現(xian),更是彌補了(le)傳(chuan)統液(ye)晶(jing)顯(xian)(xian)示(shi)(shi)上存(cun)在(zai)的(de)(de)(de)(de)不足,例如,功耗高(gao),工(gong)(gong)作電(dian)壓高(gao),輻射(she)強,并(bing)且還不能夠在(zai)短時間內實現(xian)大(da)規模的(de)(de)(de)(de)生(sheng)產,極大(da)程度的(de)(de)(de)(de)限(xian)制了(le)液(ye)晶(jing)顯(xian)(xian)示(shi)(shi)技(ji)術(shu)的(de)(de)(de)(de)發(fa)(fa)(fa)展(zhan)(zhan),而薄膜(mo)晶(jing)體(ti)管(guan)(guan),俗稱TFT卻正好相反。它(ta)對于工(gong)(gong)作條件有著非常溫和的(de)(de)(de)(de)要求,并(bing)且其體(ti)積相對來說也是大(da)為縮小。在(zai)薄膜(mo)晶(jing)體(ti)管(guan)(guan)在(zai)液(ye)晶(jing)顯(xian)(xian)示(shi)(shi)中(zhong)得到(dao)應(ying)用(yong)時,人們(men)發(fa)(fa)(fa)現(xian)其工(gong)(gong)作亮度大(da),清晰度較高(gao),因此(ci),有必要對其進行(xing)更為深(shen)入的(de)(de)(de)(de)研究。

二、概(gai)述液晶顯示技術(shu)

液晶(jing)顯(xian)示(shi)(shi)技術(shu)(shu),即是一種(zhong)為(wei)了應(ying)對越來(lai)越多(duo)的(de)動態(tai)視頻播放(fang)的(de)環境下應(ying)運而(er)生(sheng)的(de),和以往的(de)顯(xian)示(shi)(shi)技術(shu)(shu)相比(bi),將液晶(jing)顯(xian)示(shi)(shi)技術(shu)(shu)應(ying)用到大型的(de)顯(xian)示(shi)(shi)設(she)備,甚至是一些便攜式(shi)的(de)小型設(she)備中去,可以實現較(jiao)好的(de)響應(ying)度(du)(du)(du),能夠在一定程度(du)(du)(du)上滿足人們對于播放(fang)的(de)需求。在通信(xin)技術(shu)(shu)的(de)不(bu)斷推(tui)動下,液晶(jing)顯(xian)示(shi)(shi)技術(shu)(shu)更是以一種(zhong)前所未有的(de)速度(du)(du)(du)發(fa)展著。

基于(yu)(yu)TFT即薄膜晶(jing)(jing)體(ti)管的(de)(de)(de)(de)液(ye)晶(jing)(jing)顯(xian)(xian)示(shi)(shi)(shi)(shi)(shi)(shi)技術在繼承了(le)傳(chuan)統的(de)(de)(de)(de)液(ye)晶(jing)(jing)顯(xian)(xian)示(shi)(shi)(shi)(shi)(shi)(shi)技術的(de)(de)(de)(de)不(bu)足的(de)(de)(de)(de)同時(shi)(shi),更是(shi)彌補了(le)傳(chuan)統液(ye)晶(jing)(jing)顯(xian)(xian)示(shi)(shi)(shi)(shi)(shi)(shi)技術存(cun)在的(de)(de)(de)(de)不(bu)足,能(neng)夠實現(xian)高品質(zhi)的(de)(de)(de)(de)動(dong)(dong)態圖像(xiang)的(de)(de)(de)(de)播放,并且(qie)其(qi)分辨率(lv)更是(shi)大為增加。因此,可以看(kan)出(chu),基于(yu)(yu)TFT上(shang)(shang)的(de)(de)(de)(de)液(ye)晶(jing)(jing)顯(xian)(xian)示(shi)(shi)(shi)(shi)(shi)(shi)技術擁(yong)有(you)者一(yi)般的(de)(de)(de)(de)液(ye)晶(jing)(jing)顯(xian)(xian)示(shi)(shi)(shi)(shi)(shi)(shi)技術所(suo)沒有(you)的(de)(de)(de)(de)發展空(kong)間(jian)。隨著智(zhi)能(neng)手機(ji)得到(dao)普及(ji),TFT的(de)(de)(de)(de)液(ye)晶(jing)(jing)顯(xian)(xian)示(shi)(shi)(shi)(shi)(shi)(shi)技術更是(shi)在很大程(cheng)度(du)上(shang)(shang)擴展了(le)其(qi)生存(cun)空(kong)間(jian)。并且(qie)已經被應(ying)用到(dao)智(zhi)能(neng)手機(ji)的(de)(de)(de)(de)內(nei)部驅(qu)動(dong)(dong)電(dian)(dian)(dian)路(lu)(lu)上(shang)(shang),成(cheng)為顯(xian)(xian)示(shi)(shi)(shi)(shi)(shi)(shi)的(de)(de)(de)(de)主流技術。不(bu)僅如此,TFT的(de)(de)(de)(de)液(ye)晶(jing)(jing)顯(xian)(xian)示(shi)(shi)(shi)(shi)(shi)(shi)技術不(bu)僅能(neng)夠應(ying)用于(yu)(yu)手機(ji)的(de)(de)(de)(de)顯(xian)(xian)示(shi)(shi)(shi)(shi)(shi)(shi)屏,還能(neng)夠用于(yu)(yu)相機(ji),MP3等(deng)多種電(dian)(dian)(dian)子設備的(de)(de)(de)(de)顯(xian)(xian)示(shi)(shi)(shi)(shi)(shi)(shi)屏,具有(you)極(ji)其(qi)廣闊的(de)(de)(de)(de)發展前景。從驅(qu)動(dong)(dong)電(dian)(dian)(dian)路(lu)(lu)的(de)(de)(de)(de)原(yuan)理上(shang)(shang)對于(yu)(yu)TFT液(ye)晶(jing)(jing)顯(xian)(xian)示(shi)(shi)(shi)(shi)(shi)(shi)技術進行(xing)分析,可以發現(xian)這種驅(qu)動(dong)(dong)電(dian)(dian)(dian)路(lu)(lu)完全體(ti)現(xian)了(le)電(dian)(dian)(dian)路(lu)(lu)集成(cheng)化(hua)的(de)(de)(de)(de)思想(xiang),即將所(suo)有(you)的(de)(de)(de)(de)控制(zhi)(zhi)電(dian)(dian)(dian)路(lu)(lu)包(bao)括(kuo)液(ye)晶(jing)(jing)驅(qu)動(dong)(dong)電(dian)(dian)(dian)源(yuan)的(de)(de)(de)(de)控制(zhi)(zhi)、電(dian)(dian)(dian)路(lu)(lu),以及(ji)時(shi)(shi)序控制(zhi)(zhi)電(dian)(dian)(dian)路(lu)(lu)等(deng)控制(zhi)(zhi)電(dian)(dian)(dian)路(lu)(lu)集中到(dao)一(yi)塊芯片(pian)上(shang)(shang),體(ti)現(xian)了(le)微型化(hua)的(de)(de)(de)(de)思想(xiang),減小(xiao)了(le)制(zhi)(zhi)造(zao)的(de)(de)(de)(de)成(cheng)本,以及(ji)芯片(pian)所(suo)占用的(de)(de)(de)(de)面積,這種電(dian)(dian)(dian)壓的(de)(de)(de)(de)制(zhi)(zhi)造(zao)工藝主要是(shi),采用混合電(dian)(dian)(dian)壓的(de)(de)(de)(de)制(zhi)(zhi)造(zao)工藝,能(neng)夠在極(ji)短(duan)的(de)(de)(de)(de)時(shi)(shi)間(jian)內(nei)實現(xian)大規模(mo)的(de)(de)(de)(de)電(dian)(dian)(dian)信(xin)號(hao)的(de)(de)(de)(de)傳(chuan)遞。

三(san)、TFT液晶顯(xian)示驅動電(dian)路的特點

TFT的液晶顯示驅(qu)動電(dian)路有著以下幾(ji)種明顯的優勢(shi)。

(1)實現了(le)單(dan)片集成化

正如上(shang)面所說,TFT的液晶(jing)顯(xian)示驅動電(dian)(dian)(dian)路過將(jiang)時(shi)序控制電(dian)(dian)(dian)路以及液晶(jing)顯(xian)示電(dian)(dian)(dian)路集中到(dao)一(yi)個芯片中去,使得電(dian)(dian)(dian)路更(geng)為簡捷化,便于電(dian)(dian)(dian)路工(gong)作人(ren)員對其實(shi)現一(yi)定的修理及維護,因(yin)此(ci),加強了電(dian)(dian)(dian)路在實(shi)際運行(xing)中的穩定性(xing),使得電(dian)(dian)(dian)路實(shi)現更(geng)高(gao)效的工(gong)作。

(2)有利于編(bian)程的實現

編程技術指(zhi)將外界的(de)控制指(zhi)令發個硬(ying)件,硬(ying)件按(an)照相應(ying)指(zhi)令開始(shi)工作(zuo)。通過(guo)將不同的(de)電路控制系統集中(zhong)到(dao)一個芯片(pian)上(shang),并且采用多級控制的(de)曲(qu)線矯正方(fang)法,實現芯片(pian)能夠在各種不同特點(dian)的(de)液晶顯示屏幕上(shang)得(de)到(dao)應(ying)用。

(3)提(ti)高了驅動技(ji)術(shu)的應用(yong)范(fan)圍

驅(qu)動是指用軟件對(dui)硬(ying)件進(jin)行優化(hua),發揮硬(ying)件的(de)(de)(de)實際功(gong)效,讓整個液晶顯示(shi)器(qi)進(jin)行正常(chang)工作。通(tong)過在(zai)系(xi)統(tong)的(de)(de)(de)工作電路(lu)中采(cai)用細化(hua)的(de)(de)(de)工藝并(bing)且(qie)植入(ru)RAM,在(zai)一定程度上提高了(le)系(xi)統(tong)的(de)(de)(de)工作頻(pin)率(lv)以及顯示(shi)的(de)(de)(de)質量,通(tong)過這種(zhong)工藝的(de)(de)(de)使(shi)用,擴(kuo)大了(le)驅(qu)動技術的(de)(de)(de)應用范圍,使(shi)得顯示(shi)的(de)(de)(de)畫質更加的(de)(de)(de)清晰(xi)。

四(si)、對于電源的優化設(she)計的研(yan)究

為了使得(de)TFT的(de)(de)驅動(dong)電路(lu)能夠更好地應用(yong)到顯示設備中去,現(xian)(xian)在需要對于驅動(dong)電路(lu)的(de)(de)電源進行(xing)進一(yi)步(bu)研究,并且實現(xian)(xian)更低(di)的(de)(de)能耗,以下將從幾個(ge)主要方(fang)面來對于電源的(de)(de)優化(hua)設計進行(xing)研究,并且提(ti)出(chu)其(qi)具體的(de)(de)研究方(fang)向。

(1)分析驅動原(yuan)理

對(dui)于(yu)(yu)(yu)電源(yuan)(yuan)的(de)(de)優化(hua)設(she)(she)(she)計必須最終要回歸到(dao)對(dui)于(yu)(yu)(yu)TFT電路(lu)的(de)(de)顯(xian)示(shi)原(yuan)理的(de)(de)研究上,只有對(dui)于(yu)(yu)(yu)組成電路(lu)的(de)(de)各種元器件(jian)的(de)(de)工(gong)(gong)作(zuo)環境以及(ji)(ji)工(gong)(gong)作(zuo)條件(jian)達到(dao)一定的(de)(de)熟悉(xi)程(cheng)度,才能夠對(dui)于(yu)(yu)(yu)電源(yuan)(yuan)的(de)(de)優化(hua)研究進(jin)(jin)行設(she)(she)(she)計,進(jin)(jin)行電源(yuan)(yuan)優化(hua)設(she)(she)(she)計所不可缺少(shao)的(de)(de)一步就是采(cai)用(yong)校正電路(lu)以及(ji)(ji)行列控制電路(lu)對(dui)于(yu)(yu)(yu)整體的(de)(de)電路(lu)工(gong)(gong)作(zuo)結構進(jin)(jin)行建(jian)模(mo),并且要在建(jian)模(mo)的(de)(de)后期,對(dui)于(yu)(yu)(yu)模(mo)型(xing)的(de)(de)工(gong)(gong)作(zuo)效果進(jin)(jin)行預測,必要的(de)(de)時候(hou)可以通過一定的(de)(de)仿真系(xi)統(tong)進(jin)(jin)行驗(yan)證(zheng)的(de)(de)操作(zuo)。

(2)對于控制信號進行處理

信號是(shi)液晶顯示(shi)質量的(de)(de)內在因素,其(qi)強弱可(ke)以(yi)決定顯示(shi)中的(de)(de)花屏(ping)、雪(xue)花,以(yi)及清晰度,所以(yi)加(jia)強對(dui)(dui)信號的(de)(de)控(kong)制,可(ke)以(yi)從傳輸方面提(ti)高畫質質量。同(tong)時,信號會受到(dao)外(wai)界干(gan)擾,需要進(jin)行相應的(de)(de)控(kong)制和加(jia)強。在對(dui)(dui)于驅(qu)動電路的(de)(de)各個部件的(de)(de)功能進(jin)行了解(jie)的(de)(de)基礎上,對(dui)(dui)于驅(qu)動電路的(de)(de)寄存器(qi)以(yi)及控(kong)制信號進(jin)行處理(li),保證系統的(de)(de)工作效率。

結語

隨著人們(men)生活水(shui)平的逐漸提(ti)高,人們(men)對液晶(jing)顯(xian)示(shi)的要求越(yue)(yue)來越(yue)(yue)高,并成為(wei)一(yi)種社會需求。液晶(jing)顯(xian)示(shi)質量(liang)的提(ti)高主要依賴于(yu)兩(liang)個方面,一(yi)方面是(shi)顯(xian)示(shi)驅動(dong)(dong)電路,另(ling)一(yi)方面是(shi)顯(xian)示(shi)電源(yuan)。兩(liang)者的有效優(you)化(hua),可以大幅提(ti)升(sheng)液晶(jing)顯(xian)示(shi)效果。本文(wen)通(tong)過對于(yu)TFT的液晶(jing)顯(xian)示(shi)技(ji)(ji)術(shu)進(jin)行(xing)探討,并且對于(yu)建立在其工(gong)作原理上的液晶(jing)顯(xian)示(shi)驅動(dong)(dong)電路進(jin)行(xing)優(you)化(hua)設計,能夠在一(yi)定范圍內提(ti)升(sheng)顯(xian)示(shi)畫(hua)面質量(liang)。通(tong)過對于(yu)TFT的液晶(jing)顯(xian)示(shi)的原理進(jin)行(xing)分析(xi),提(ti)升(sheng)了系統工(gong)作的穩(wen)定性,推(tui)動(dong)(dong)了液晶(jing)顯(xian)示(shi)技(ji)(ji)術(shu)的發展。

參考文獻

[1]楊靜(jing),吳乃陵.嵌(qian)入式操(cao)作系(xi)統應(ying)用研究[J].電子器件,2014(01).

篇3

關鍵詞:驅動控(kong)制(zhi);單(dan)片機;CPLD;壓電陶瓷

DOI:10.16640/ki.37-1222/t.2017.04.055

1 引言

壓(ya)電(dian)(dian)陶瓷(ci)式噴(pen)墨(mo)頭(tou)(tou)具有(you)可(ke)控制,精度(du)高等(deng)優點,對于(yu)數(shu)字噴(pen)墨(mo)印(yin)刷系統噴(pen)印(yin)質量(liang)的(de)(de)(de)提升(sheng)以(yi)及打印(yin)速(su)度(du)的(de)(de)(de)加快具有(you)重要意義(yi)。壓(ya)電(dian)(dian)式噴(pen)墨(mo)頭(tou)(tou)噴(pen)出(chu)的(de)(de)(de)墨(mo)滴大(da)小以(yi)及噴(pen)射速(su)度(du)和(he)(he)均勻性(xing)都會對噴(pen)印(yin)質量(liang)產(chan)生影響,壓(ya)電(dian)(dian)陶瓷(ci)形(xing)(xing)變的(de)(de)(de)大(da)小和(he)(he)頻(pin)(pin)率是(shi)決定輸出(chu)墨(mo)滴性(xing)能的(de)(de)(de)主要影響因(yin)素(su),而驅動(dong)(dong)電(dian)(dian)源(yuan)輸出(chu)激勵脈沖電(dian)(dian)壓(ya)的(de)(de)(de)大(da)小決定了(le)壓(ya)電(dian)(dian)陶瓷(ci)片(pian)(pian)的(de)(de)(de)形(xing)(xing)變量(liang);激勵脈沖的(de)(de)(de)頻(pin)(pin)率影響著陶瓷(ci)片(pian)(pian)的(de)(de)(de)形(xing)(xing)變速(su)度(du),因(yin)此驅動(dong)(dong)電(dian)(dian)源(yuan)的(de)(de)(de)性(xing)能決定了(le)噴(pen)墨(mo)的(de)(de)(de)質量(liang)。本文(wen)設計的(de)(de)(de)是(shi)基于(yu)單片(pian)(pian)機和(he)(he)CPLD的(de)(de)(de)壓(ya)電(dian)(dian)噴(pen)墨(mo)頭(tou)(tou)驅動(dong)(dong)電(dian)(dian)源(yuan)系統,其(qi)中單片(pian)(pian)機和(he)(he)CPLD是(shi)核心(xin)處理(li)(li)芯(xin)片(pian)(pian),基于(yu)DDS原理(li)(li)產(chan)生的(de)(de)(de)數(shu)字可(ke)控低壓(ya)脈沖激勵波形(xing)(xing),經集(ji)成放大(da)模塊放大(da)后以(yi)驅動(dong)(dong)。

2 驅動電源的硬件設計

該(gai)系統(tong)以(yi)宏晶科技(ji)生產(chan)的STC89C52RC單片機(ji),Altera公司的MAX II系列的EPM240T100C5N CPLD芯片和基于DDS原理的波形(xing)生成(cheng)電(dian)路為核心。圖(tu)1是驅動電(dian)源控制系統(tong)結(jie)構框圖(tu)。

在系統中,單(dan)(dan)片(pian)機作為主(zhu)要(yao)控(kong)制(zhi)(zhi)(zhi)器,基于DDS波形(xing)生(sheng)成(cheng)技術(shu),由單(dan)(dan)片(pian)機和(he)CPLD共同(tong)生(sheng)成(cheng)控(kong)制(zhi)(zhi)(zhi)波形(xing)。單(dan)(dan)片(pian)機與計(ji)算機系統連接以實(shi)現(xian)數(shu)據(ju)通(tong)訊,CPLD和(he)DAC在單(dan)(dan)片(pian)機控(kong)制(zhi)(zhi)(zhi)下生(sheng)成(cheng)低壓(ya)(ya)的激勵脈沖(chong),經過二階有源低通(tong)濾波器濾波后,由PA84放大(da)器將(jiang)(jiang)其脈沖(chong)放大(da),按(an)照(zhao)時序控(kong)制(zhi)(zhi)(zhi)要(yao)求將(jiang)(jiang)高(gao)壓(ya)(ya)脈沖(chong)傳(chuan)送到噴頭接口芯(xin)片(pian)控(kong)制(zhi)(zhi)(zhi)噴頭工作。

2.1 STC89C52RC單片機和EPM240T100C5N CPLD

選用STC89C52RC單片機作為(wei)系(xi)統(tong)(tong)核心控制(zhi)元件(jian),其(qi)處理和存(cun)儲能力強,運(yun)行速度快,可(ke)為(wei)控制(zhi)系(xi)統(tong)(tong)提供良好的硬件(jian)平臺。STC89C52RC單片機是基于(yu)8051的內核發展起(qi)來的,主要特性是加密性強不可(ke)解密;超強的抗干(gan)擾技術;功耗低;具有ISC在線編輯功能。

EPM240T100C5N CPLD芯片(pian)具有192個邏輯宏(hong)單元,可(ke)以(yi)滿足我們(men)的(de)開(kai)發(fa)要(yao)求;每一(yi)個芯片(pian)都內置8Kb的(de)Flash存儲(chu)器,其中配(pei)置數(shu)據(ju)在存儲(chu)器內部,可(ke)進行在線編輯,使(shi)得當(dang)整(zheng)個硬(ying)件(jian)系統設計(ji)完成后,計(ji)算機還可(ke)以(yi)通過ISP接口對(dui)CPLD進行重新(xin)配(pei)置。

2.2 基(ji)于DDS原理的波形生(sheng)成電路

DDS指的(de)(de)(de)(de)是直接數(shu)(shu)字頻(pin)(pin)率(lv)合成(cheng)(cheng)技術。DDS具有(you)超高頻(pin)(pin)率(lv)的(de)(de)(de)(de)分辨率(lv);可以根(gen)據不同(tong)的(de)(de)(de)(de)波(bo)(bo)形(xing)(xing)數(shu)(shu)據形(xing)(xing)成(cheng)(cheng)任意波(bo)(bo)形(xing)(xing)。基(ji)于DDS原理,使用CPLD進行電(dian)路(lu)設(she)計的(de)(de)(de)(de)波(bo)(bo)形(xing)(xing)生(sheng)(sheng)成(cheng)(cheng)電(dian)路(lu)是驅動電(dian)源的(de)(de)(de)(de)核(he)心。圖(tu)2所示DDS的(de)(de)(de)(de)波(bo)(bo)形(xing)(xing)發(fa)生(sheng)(sheng)電(dian)路(lu)。由單(dan)片(pian)機(ji)向波(bo)(bo)形(xing)(xing)生(sheng)(sheng)成(cheng)(cheng)電(dian)路(lu)提供頻(pin)(pin)率(lv)控(kong)制(zhi)字K,通(tong)過在一定的(de)(de)(de)(de)范圍內改(gai)變K的(de)(de)(de)(de)大(da)小(xiao),進而改(gai)變脈(mo)(mo)沖(chong)頻(pin)(pin)率(lv)的(de)(de)(de)(de)大(da)小(xiao)。CPLD模(mo)塊生(sheng)(sheng)成(cheng)(cheng)地址累加器,通(tong)過頻(pin)(pin)率(lv)控(kong)制(zhi)字K的(de)(de)(de)(de)變化(hua)來改(gai)變地址。程序存儲器ROM是用來儲存波(bo)(bo)形(xing)(xing)數(shu)(shu)據的(de)(de)(de)(de)波(bo)(bo)形(xing)(xing)存儲器,ROM中存儲著波(bo)(bo)形(xing)(xing)的(de)(de)(de)(de)查(cha)找表(biao),查(cha)找表(biao)中的(de)(de)(de)(de)對應(ying)地址隨著K值的(de)(de)(de)(de)變化(hua)而變化(hua),查(cha)找表(biao)將地址信息所對應(ying)的(de)(de)(de)(de)波(bo)(bo)形(xing)(xing)幅度(du)信息傳送到數(shu)(shu)模(mo)轉(zhuan)換芯(xin)片(pian),DAC就可以將CPLD所生(sheng)(sheng)成(cheng)(cheng)的(de)(de)(de)(de)波(bo)(bo)形(xing)(xing)數(shu)(shu)據轉(zhuan)化(hua)成(cheng)(cheng)模(mo)擬波(bo)(bo)形(xing)(xing),之(zhi)后再經過濾波(bo)(bo)生(sheng)(sheng)成(cheng)(cheng)低壓的(de)(de)(de)(de)激(ji)勵(li)脈(mo)(mo)沖(chong)。

3 系統硬件設計與實(shi)現

為了(le)獲取滿足噴墨頭(tou)工作要(yao)求的(de)(de)(de)激(ji)(ji)勵脈(mo)沖(chong),需要(yao)設計(ji)完整的(de)(de)(de)驅(qu)(qu)(qu)動(dong)電(dian)源(yuan)硬件(jian)。驅(qu)(qu)(qu)動(dong)電(dian)源(yuan)硬件(jian)系(xi)統包括單(dan)(dan)(dan)(dan)片(pian)機(ji)(ji)控制(zhi)單(dan)(dan)(dan)(dan)元(yuan)(yuan)(yuan)(yuan);波形生成單(dan)(dan)(dan)(dan)元(yuan)(yuan)(yuan)(yuan);振(zhen)幅控制(zhi)單(dan)(dan)(dan)(dan)元(yuan)(yuan)(yuan)(yuan);液晶顯示單(dan)(dan)(dan)(dan)元(yuan)(yuan)(yuan)(yuan);濾(lv)波單(dan)(dan)(dan)(dan)元(yuan)(yuan)(yuan)(yuan);高(gao)壓放大單(dan)(dan)(dan)(dan)元(yuan)(yuan)(yuan)(yuan);串口轉換單(dan)(dan)(dan)(dan)元(yuan)(yuan)(yuan)(yuan);噴墨頭(tou)的(de)(de)(de)接口單(dan)(dan)(dan)(dan)元(yuan)(yuan)(yuan)(yuan)。前七個單(dan)(dan)(dan)(dan)元(yuan)(yuan)(yuan)(yuan)組合是為了(le)實現振(zhen)幅頻率數(shu)字可控的(de)(de)(de)高(gao)壓激(ji)(ji)勵脈(mo)沖(chong)的(de)(de)(de)輸出;最(zui)后一個單(dan)(dan)(dan)(dan)元(yuan)(yuan)(yuan)(yuan)可以完成數(shu)據(ju)信號與高(gao)壓脈(mo)沖(chong)激(ji)(ji)勵的(de)(de)(de)匹配,處理有關(guan)于激(ji)(ji)勵脈(mo)沖(chong)的(de)(de)(de)電(dian)信號;噴墨頭(tou)噴嘴的(de)(de)(de)時序控制(zhi)。單(dan)(dan)(dan)(dan)片(pian)機(ji)(ji)與計(ji)算(suan)機(ji)(ji)系(xi)統連接以實現數(shu)據(ju)通訊,主控電(dian)路由單(dan)(dan)(dan)(dan)片(pian)機(ji)(ji)控制(zhi)CPLD和DAC生成低壓的(de)(de)(de)激(ji)(ji)勵脈(mo)沖(chong),低壓脈(mo)沖(chong)經過二階(jie)有源(yuan)低通濾(lv)波器(qi)進行濾(lv)波后,由PA84放大器(qi)將其(qi)高(gao)壓線(xian)性放大成高(gao)壓脈(mo)沖(chong),并送至(zhi)噴頭(tou)驅(qu)(qu)(qu)動(dong)芯(xin)(xin)片(pian),由驅(qu)(qu)(qu)動(dong)芯(xin)(xin)片(pian)控制(zhi)噴墨頭(tou)的(de)(de)(de)工作。

4 系統軟件設(she)計與仿真

驅動電源的(de)軟件設計包括在(zai)KeliuVison4中使(shi)用(yong)C語言(yan)對(dui)單片機的(de)控制;在(zai)QuartusII環境中使(shi)用(yong)硬件描(miao)述語言(yan)VHDL對(dui)CPLD進行控制,以及使(shi)用(yong)Matlab軟件對(dui)CPLD進行數字波形的(de)仿真(zhen)。

4.1 單片機C語(yu)言(yan)主程序(xu)

單片機(ji)程序包含(han)在頭文件#include中(zhong),其中(zhong)包括了(le)單片機(ji)的(de)寄(ji)存器定(ding)義,引腳定(ding)義等功(gong)能。初始(shi)(shi)化(hua)程序void init()包括變量(liang)和常(chang)量(liang)的(de)幅值(zhi)和初值(zhi)定(ding)義;定(ding)時(shi)中(zhong)斷的(de)初始(shi)(shi)化(hua);串口初始(shi)(shi)化(hua)和液晶(jing)初始(shi)(shi)化(hua)。液晶(jing)顯示函(han)數(shu)(shu)void display()是(shi)為(wei)了(le)在LCD1602顯示振幅和頻(pin)率。主程序void main()是(shi)函(han)數(shu)(shu)的(de)主體(ti)。定(ding)時(shi)中(zhong)斷函(han)數(shu)(shu)是(shi)為(wei)了(le)精準的(de)定(ding)位。

4.2 基于VHDL語(yu)言(yan)的(de)程(cheng)序流(liu)程(cheng)

圖3為(wei)VHDL生成梯形波的(de)程序(xu)圖。在使能端有效時,程序(xu)執行。當需(xu)要(yao)的(de)信號都(dou)有效時,累(lei)(lei)加(jia)(jia)器(qi)工作,累(lei)(lei)加(jia)(jia)器(qi)判斷是(shi)否達(da)(da)到規定(ding)值(zhi)M,如果達(da)(da)到,計數(shu)(shu)值(zhi)清(qing)零,如果沒有,則計數(shu)(shu)值(zhi)加(jia)(jia)上(shang)步長K。之后(hou)ROM表根據(ju)(ju)累(lei)(lei)加(jia)(jia)器(qi)的(de)值(zhi)對應給出(chu)波形數(shu)(shu)據(ju)(ju),并將其傳送(song)到寄(ji)存器(qi)中,在下一個數(shu)(shu)據(ju)(ju)到來時將數(shu)(shu)據(ju)(ju)輸出(chu)到DAC。

4.3 使用Matlab軟(ruan)件對CPLD進行(xing)數字波形的(de)仿真。

由于QuartusII進行功能(neng)仿(fang)真后形成(cheng)的(de)(de)波形不(bu)易看(kan)出波形的(de)(de)形狀,所以(yi)使用(yong)(yong)Matlab語言將仿(fang)真結(jie)果轉(zhuan)換成(cheng)Matlab中的(de)(de)波形曲線。利用(yong)(yong)QuartusII的(de)(de)表(biao)格文(wen)(wen)件(.tbl文(wen)(wen)件)仿(fang)真,即在功能(neng)仿(fang)真結(jie)束時(shi),將波形文(wen)(wen)件另存為.tbl文(wen)(wen)件,然后再使用(yong)(yong)Matlab編寫程序(xu)進行調用(yong)(yong)。

5 結束語

本(ben)文介紹了基于DDS原理,在單(dan)片機和CPLD的(de)(de)基礎上的(de)(de)壓電陶瓷(ci)噴墨頭(tou)電壓驅動電源(yuan)系統(tong),該設計方案(an)開發(fa)周期短,硬件連接簡單(dan),可控行比較好,能夠(gou)基本(ben)實現壓電陶瓷(ci)噴墨頭(tou)電源(yuan)驅動。

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篇4

關鍵詞:LED背(bei)光;DC-DC;脈寬調制;反饋(kui)

中圖分類號(hao):TN312+.8文獻標識碼:B

A Design of Wide Color Gamut Direct LED Backlight Driver Circuit

ZHANG Zhi-rui1, LIU Wei-dong1,2, QIAO Ming-sheng2

(1. Dept.of Electrical Engineering, Ocean University of China, Qingdao Shandong 266100, China; 2. Hisense Electric Co., Ltd., Qingdao Shandong 266071, China)

Abstract: This paper presents a wide color gamut LED backlight driver circuit, introduces the process of hardware design in detail, briefly shows the process how the FPGA control the LED driver.

Keywords: LED backlight; DC-DC; PWM; feedback

引言

LED背(bei)光(guang)(guang)(guang)(guang)源(yuan)液(ye)晶電(dian)視以(yi)(yi)(yi)(yi)其特有的高(gao)性能(neng)獲得越來(lai)越多地(di)關注(zhu),目前市場(chang)上(shang)的LED背(bei)光(guang)(guang)(guang)(guang)源(yuan)液(ye)晶電(dian)視大多以(yi)(yi)(yi)(yi)白光(guang)(guang)(guang)(guang)LED為(wei)主,對比(bi)CCFL背(bei)光(guang)(guang)(guang)(guang)電(dian)視,白光(guang)(guang)(guang)(guang)LED背(bei)光(guang)(guang)(guang)(guang)電(dian)視無論(lun)在色(se)(se)(se)域、對比(bi)度(du)還(huan)是安全、綠色(se)(se)(se)環保(bao)方(fang)面都有其無法比(bi)擬的優(you)勢[1]。直下(xia)式背(bei)光(guang)(guang)(guang)(guang)模(mo)組的LED安裝在背(bei)光(guang)(guang)(guang)(guang)模(mo)組底面,其出光(guang)(guang)(guang)(guang)可以(yi)(yi)(yi)(yi)高(gao)效(xiao)率地(di)耦合(he)到(dao)液(ye)晶面板,在大尺寸LCD應用中(zhong)能(neng)保(bao)證(zheng)均勻的亮(liang)度(du)分布。而以(yi)(yi)(yi)(yi)紅(hong)、綠、藍三色(se)(se)(se)LED按一(yi)定(ding)比(bi)例(li)構成白光(guang)(guang)(guang)(guang)時,雖然能(neng)夠大幅改進液(ye)晶電(dian)視的顏色(se)(se)(se)與亮(liang)度(du)性能(neng),但由(you)于(yu)過高(gao)的價格(ge)和難以(yi)(yi)(yi)(yi)克服的色(se)(se)(se)衰(shuai)不一(yi)致(zhi)問題,一(yi)直未得到(dao)長足(zu)的發展[2]。本(ben)文討論(lun)以(yi)(yi)(yi)(yi)獨特雙色(se)(se)(se)管芯(xin)白光(guang)(guang)(guang)(guang)LED光(guang)(guang)(guang)(guang)源(yuan)作為(wei)液(ye)晶電(dian)視背(bei)光(guang)(guang)(guang)(guang)源(yuan),其采(cai)用三合(he)一(yi)封(feng)裝,由(you)一(yi)個紅(hong)色(se)(se)(se)管芯(xin)和兩個紅(hong)色(se)(se)(se)互(hu)補色(se)(se)(se)管芯(xin)組成,實驗證(zheng)明(ming)其色(se)(se)(se)域能(neng)達(da)到(dao)NTSC(national television system committee)標準90%以(yi)(yi)(yi)(yi)上(shang),但價格(ge)卻遠遠低于(yu)RGB LED,且(qie)性能(neng)更加穩定(ding)。

相比普通(tong)白光(guang)LED背(bei)光(guang)源,本文討論的(de)大尺寸(cun)寬(kuan)色域直下(xia)式LED背(bei)光(guang)源兩倍于相同數量的(de)白光(guang)LED通(tong)路(lu)數量,需要(yao)更多的(de)驅動(dong)芯片以(yi)適應其(qi)需要(yao),因此16通(tong)路(lu)的(de)驅動(dong)芯片在性(xing)價比方(fang)面有很大優(you)勢(shi)。文中以(yi)16通(tong)路(lu)驅動(dong)芯片配合雙路(lu)升、降壓(ya)DC-DC控(kong)制芯片來實(shi)現雙管芯LED背(bei)光(guang)控(kong)制,結構(gou)簡單且控(kong)制方(fang)便(bian)。

1整體設計

整個背光驅動(dong)(dong)系統由(you)DC-DC電(dian)路(lu)、LED驅動(dong)(dong)電(dian)路(lu)、反饋電(dian)路(lu)組(zu)成。FPGA對(dui)驅動(dong)(dong)芯片(pian)(pian)進(jin)行前(qian)端(duan)控制,設(she)計中(zhong)DC-DC為LED陣(zhen)列(lie)提供穩定的(de)(de)電(dian)壓(ya)(ya),驅動(dong)(dong)芯片(pian)(pian)使(shi)LED陣(zhen)列(lie)保(bao)持(chi)(chi)恒流,以達到LED燈(deng)串(chuan)亮(liang)度(du)的(de)(de)高(gao)度(du)一致,并保(bao)證在整體電(dian)流不變的(de)(de)情況(kuang)下(xia),利(li)用(yong)FPGA對(dui)輸入(ru)圖(tu)像信(xin)號進(jin)行亮(liang)度(du)提取,產(chan)生對(dui)應(ying)占空(kong)比的(de)(de)PWM方波(bo)控制LED點亮(liang)或者熄(xi)滅,對(dui)LED進(jin)行亮(liang)度(du)控制[3]。驅動(dong)(dong)電(dian)路(lu)的(de)(de)反饋電(dian)路(lu)能使(shi)輸出電(dian)壓(ya)(ya)根(gen)據每串(chuan)燈(deng)電(dian)壓(ya)(ya)的(de)(de)數值進(jin)行自(zi)適應(ying)調(diao)節,使(shi)其輸出電(dian)壓(ya)(ya)保(bao)持(chi)(chi)在最(zui)佳值,并保(bao)證驅動(dong)(dong)芯片(pian)(pian)的(de)(de)高(gao)效率。整體框(kuang)圖(tu)如圖(tu)1所示。

2硬件結構設計

2.1電源(yuan)驅動模塊系統設(she)計(ji)

本系統電(dian)(dian)源提供(gong)24V電(dian)(dian)壓,由于雙色(se)管芯(xin)(xin)白光LED需(xu)(xu)要兩個(ge)不(bu)同(tong)的(de)電(dian)(dian)壓驅動(dong)(dong),因(yin)此DC-DC控制器的(de)選擇(ze)尤為重要,考慮(lv)到DC-DC控制器的(de)簡易性,選擇(ze)雙路DC-DC以實(shi)現升、降壓輸出,簡化了電(dian)(dian)源模(mo)塊(DC-DC)的(de)設計,將24V電(dian)(dian)源轉換(huan)成各(ge)個(ge)模(mo)塊所需(xu)(xu)電(dian)(dian)源。由于雙色(se)管芯(xin)(xin)白光LED燈不(bu)同(tong)顏色(se)芯(xin)(xin)片的(de)前向壓降和驅動(dong)(dong)電(dian)(dian)流不(bu)同(tong),因(yin)此需(xu)(xu)要不(bu)同(tong)的(de)驅動(dong)(dong)芯(xin)(xin)片進(jin)行驅動(dong)(dong)。

由于LED的(de)光特性(xing)通常都描述為電流(liu)的(de)函數(shu),而不(bu)是電壓的(de)函數(shu),而且Vf的(de)微(wei)小變化(hua)會引起較(jiao)大(da)的(de)If變化(hua),從而引起亮(liang)度的(de)較(jiao)大(da)變化(hua)。所以,采(cai)用(yong)恒壓源(yuan)驅(qu)(qu)動不(bu)能(neng)保證LED亮(liang)度的(de)一致性(xing),而且影響LED的(de)可靠(kao)性(xing)、壽命和光衰,因(yin)此本設計中LED燈串采(cai)用(yong)恒流(liu)驅(qu)(qu)動。

驅動芯片整體電(dian)(dian)(dian)路(lu)主要(yao)(yao)分為電(dian)(dian)(dian)流(liu)調節電(dian)(dian)(dian)路(lu)和數(shu)字邏輯控(kong)(kong)制(zhi)(zhi)電(dian)(dian)(dian)路(lu)兩部(bu)(bu)分,加(jia)上(shang)其它(ta)輔助電(dian)(dian)(dian)路(lu)實(shi)(shi)(shi)現完整的(de)電(dian)(dian)(dian)路(lu)功能。電(dian)(dian)(dian)流(liu)調節電(dian)(dian)(dian)路(lu)主要(yao)(yao)用于通過外(wai)部(bu)(bu)調節電(dian)(dian)(dian)阻實(shi)(shi)(shi)現對輸出電(dian)(dian)(dian)流(liu)大小的(de)控(kong)(kong)制(zhi)(zhi)和調節,在保證LED燈可靠性與安全(quan)性的(de)前(qian)提(ti)下,達到液(ye)晶(jing)電(dian)(dian)(dian)視背光(guang)模組的(de)亮度需(xu)要(yao)(yao)。數(shu)字邏輯控(kong)(kong)制(zhi)(zhi)電(dian)(dian)(dian)路(lu)部(bu)(bu)分主要(yao)(yao)用于外(wai)部(bu)(bu)數(shu)據的(de)接收、鎖存(cun)以及使能控(kong)(kong)制(zhi)(zhi)功能,結合(he)時間延遲(chi)電(dian)(dian)(dian)路(lu),芯片內部(bu)(bu)集成8位PWM寄存(cun)器(qi),實(shi)(shi)(shi)現對LED陣列256級亮度控(kong)(kong)制(zhi)(zhi)。

2.2DC-DC電路(lu)控制芯片的(de)選擇與特性

本(ben)方案設計(ji)的(de)液(ye)晶電(dian)視背光模組,每(mei)個燈(deng)串有9顆LED串聯組成(cheng),雙色管(guan)芯白光LED燈(deng)由于(yu)各自的(de)前向(xiang)壓(ya)降(jiang)不同(tong),經測試在各自不同(tong)的(de)驅動電(dian)流下,每(mei)串分別需要18.7V、29.8V電(dian)壓(ya)。雙路輸出DC-DC控制(zhi)器原理圖(tu)如圖(tu)2所示(shi)。

整(zheng)(zheng)個系(xi)統輸入電(dian)壓(ya)為24V,綜(zong)合(he)考(kao)慮,選用(yong)ROHM9011轉換芯(xin)片(pian)(pian),該DC-DC控(kong)制器采用(yong)電(dian)感式開關結構(gou),運(yun)用(yong)電(dian)流(liu)/電(dian)壓(ya)雙(shuang)(shuang)路反(fan)饋控(kong)制、PWM調(diao)制以(yi)及(ji)同步(bu)整(zheng)(zheng)流(liu)控(kong)制,電(dian)流(liu)模式PWM控(kong)制采用(yong)雙(shuang)(shuang)閉環(huan)控(kong)制,提(ti)高(gao)(gao)了(le)(le)(le)系(xi)統的(de)(de)(de)瞬態響應速度,增強了(le)(le)(le)系(xi)統的(de)(de)(de)穩定(ding)性(xing)。同步(bu)整(zheng)(zheng)流(liu)技術采用(yong)功率(lv)NMOS管替代(dai)肖特(te)基整(zheng)(zheng)流(liu)二極管,消除了(le)(le)(le)二極管死區電(dian)壓(ya)的(de)(de)(de)功耗(hao)(hao)影響,可(ke)以(yi)提(ti)高(gao)(gao)芯(xin)片(pian)(pian)的(de)(de)(de)工作效率(lv)[4],優化(hua)芯(xin)片(pian)(pian)的(de)(de)(de)性(xing)能,滿載效率(lv)達到90%以(yi)上。而且單顆芯(xin)片(pian)(pian)可(ke)以(yi)實(shi)現雙(shuang)(shuang)路輸出,以(yi)滿足不同顏(yan)色芯(xin)片(pian)(pian)對電(dian)壓(ya)的(de)(de)(de)需求,簡化(hua)了(le)(le)(le)PCB布局(ju),具有很高(gao)(gao)的(de)(de)(de)集成度。表1為同步(bu)整(zheng)(zheng)流(liu)和之前非同步(bu)整(zheng)(zheng)流(liu)兩種方式的(de)(de)(de)效率(lv)比較,由數據可(ke)知(zhi),同步(bu)整(zheng)(zheng)流(liu)極大(da)提(ti)高(gao)(gao)了(le)(le)(le)系(xi)統的(de)(de)(de)效率(lv),對系(xi)統的(de)(de)(de)功耗(hao)(hao)降低和系(xi)統的(de)(de)(de)穩定(ding)有著積極意義。

2.3DC-DC控制(zhi)器工作過程

2.3.1降(jiang)壓電(dian)路VR

當(dang)Q1導(dao)通(tong)(tong)時(shi),在(zai)電(dian)(dian)(dian)(dian)感(gan)(gan)L3中感(gan)(gan)應(ying)(ying)出左“+”右(you)(you)“-”的感(gan)(gan)應(ying)(ying)電(dian)(dian)(dian)(dian)動(dong)勢(shi),續(xu)流二極管(guan)VD5關(guan)閉(bi)。LED的供電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)壓通(tong)(tong)過(guo)電(dian)(dian)(dian)(dian)感(gan)(gan)L3后,經(jing)過(guo)LED燈(deng)串,經(jing)驅動(dong)芯(xin)片內部(bu)MOSFET后接(jie)地,形(xing)成回路。當(dang)Q1關(guan)閉(bi)時(shi),由于電(dian)(dian)(dian)(dian)感(gan)(gan)電(dian)(dian)(dian)(dian)流不能突變,在(zai)電(dian)(dian)(dian)(dian)感(gan)(gan)L3中感(gan)(gan)應(ying)(ying)出左“-”右(you)(you)“+”的感(gan)(gan)應(ying)(ying)電(dian)(dian)(dian)(dian)動(dong)勢(shi);Q2導(dao)通(tong)(tong),電(dian)(dian)(dian)(dian)流經(jing)電(dian)(dian)(dian)(dian)感(gan)(gan)L3,Q2內部(bu)寄存二極管(guan),LED燈(deng)串形(xing)成回路。輸出電(dian)(dian)(dian)(dian)壓由Q1的導(dao)通(tong)(tong)時(shi)間決(jue)定(ding),二極管(guan)VD5的作(zuo)用主(zhu)要為(wei)防(fang)止芯(xin)片誤操作(zuo),即當(dang)Q1關(guan)閉(bi)后Q2沒有導(dao)通(tong)(tong),從而(er)引起Q2毀壞。

2.3.2升壓電路VB

當(dang)Q3導通時,電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流通過(guo)L2經Q3到(dao)地(di),電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源對(dui)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)感進行充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian),在電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)感線圈未飽和之前電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流線性(xing)增加,電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)能(neng)以磁(ci)能(neng)形式存(cun)(cun)儲在電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)感線圈L2中(zhong)。由(you)(you)于開(kai)關(guan)管(guan)(guan)導通,二極(ji)(ji)管(guan)(guan)承受反向(xiang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya),此時電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)C2向(xiang)LED燈(deng)串放電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)。當(dang)晶體管(guan)(guan)Q3關(guan)斷時,由(you)(you)于線圈L2中(zhong)的(de)(de)(de)(de)磁(ci)場將改變線圈L2兩端的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)極(ji)(ji)性(xing)以保持電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流不(bu)變,這樣(yang)線圈L2磁(ci)能(neng)轉化成(cheng)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)與電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源串聯,同時向(xiang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)容(rong)C2、負載供電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)。L2電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流是連(lian)續(xu)的(de)(de)(de)(de),但流經二極(ji)(ji)管(guan)(guan)VD2的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流是脈動(dong)的(de)(de)(de)(de),且由(you)(you)于C2的(de)(de)(de)(de)存(cun)(cun)在,LED燈(deng)串上仍具有穩定連(lian)續(xu)的(de)(de)(de)(de)負載電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流。

本設計(ji)采用電(dian)流(liu)(liu)(liu)控制(zhi)模式,它是(shi)(shi)一種固(gu)定時鐘開啟、峰值電(dian)流(liu)(liu)(liu)關斷的控制(zhi)方法,電(dian)流(liu)(liu)(liu)控制(zhi)模式把變換器分成電(dian)流(liu)(liu)(liu)、電(dian)壓(ya)兩條控制(zhi)環路。輸(shu)出電(dian)壓(ya)Vout經過反(fan)饋電(dian)路分壓(ya)電(dian)阻(zu)R14、R15分壓(ya)后(hou)送入誤差(cha)(cha)放(fang)大(da)(da)器的反(fan)相輸(shu)入端(duan),而放(fang)大(da)(da)器的同相輸(shu)入端(duan)為精(jing)密溫度補(bu)償基(ji)準(zhun)電(dian)壓(ya)VREF,兩者之差(cha)(cha)被放(fang)大(da)(da)后(hou)與(yu)電(dian)感電(dian)流(liu)(liu)(liu)的采樣信號(hao)相比較,決定是(shi)(shi)否關斷開關管(guan)。DC-DC反(fan)饋電(dian)路是(shi)(shi)保(bao)證在輸(shu)入電(dian)壓(ya)發生變化或者負載變化的情況下使電(dian)路輸(shu)出電(dian)壓(ya)保(bao)持穩定。

2.4驅動芯片特性

本方(fang)案(an)中(zhong)驅(qu)(qu)動(dong)(dong)芯片(pian)(pian)選用(yong)(yong)MSL3162,共有(you)16通(tong)道(dao)(dao)(dao),內部每個通(tong)道(dao)(dao)(dao)亮度(du)寄(ji)存器的(de)長度(du)是8位(wei),每個通(tong)道(dao)(dao)(dao)可(ke)以通(tong)過PWM方(fang)式(shi)(shi)根(gen)據內部亮度(du)寄(ji)存器的(de)值(zhi)進行256級亮度(du)控制。另外,驅(qu)(qu)動(dong)(dong)電(dian)(dian)(dian)流(liu)(liu)(liu)(liu)的(de)最(zui)大(da)值(zhi)可(ke)通(tong)過片(pian)(pian)外電(dian)(dian)(dian)阻設定,在4.5~5.5V的(de)輸(shu)入電(dian)(dian)(dian)壓范圍內,可(ke)實(shi)現對LED的(de)恒流(liu)(liu)(liu)(liu)驅(qu)(qu)動(dong)(dong),每通(tong)道(dao)(dao)(dao)最(zui)大(da)驅(qu)(qu)動(dong)(dong)能力為100mA,可(ke)根(gen)據需要自由調(diao)節(jie)。電(dian)(dian)(dian)路擁有(you)典型值(zhi)為3%的(de)各通(tong)道(dao)(dao)(dao)間(jian)的(de)電(dian)(dian)(dian)流(liu)(liu)(liu)(liu)匹(pi)配(pei)精(jing)度(du),整個驅(qu)(qu)動(dong)(dong)電(dian)(dian)(dian)路相當于恒流(liu)(liu)(liu)(liu)源,可(ke)消除因溫度(du)和工(gong)藝引(yin)起(qi)的(de)正向電(dian)(dian)(dian)壓變化所導致的(de)電(dian)(dian)(dian)流(liu)(liu)(liu)(liu)變化。MSL3162相比(bi)以往(wang)常(chang)用(yong)(yong)的(de)8通(tong)道(dao)(dao)(dao)LED恒流(liu)(liu)(liu)(liu)驅(qu)(qu)動(dong)(dong)器,具有(you)更(geng)(geng)強的(de)多通(tong)道(dao)(dao)(dao)驅(qu)(qu)動(dong)(dong)能力、更(geng)(geng)優的(de)輸(shu)出(chu)電(dian)(dian)(dian)流(liu)(liu)(liu)(liu)調(diao)節(jie)精(jing)度(du)以及更(geng)(geng)高的(de)電(dian)(dian)(dian)流(liu)(liu)(liu)(liu)匹(pi)配(pei)精(jing)度(du),同時(shi)還擁有(you)較(jiao)小的(de)芯片(pian)(pian)面積,有(you)利(li)于大(da)尺寸直下式(shi)(shi)LED背光電(dian)(dian)(dian)視驅(qu)(qu)動(dong)(dong)設計。1MHz I2C接口(kou)用(yong)(yong)于數(shu)據傳輸(shu)和錯誤偵測,在串行總線上(shang)可(ke)最(zui)多帶16個驅(qu)(qu)動(dong)(dong)芯片(pian)(pian),其物理地址(zhi)可(ke)通(tong)過AD1、AD0引(yin)腳進行硬件配(pei)置。實(shi)際應用(yong)(yong)原理圖如(ru)圖3所示。

本文(wen)LED驅動(dong)芯片電(dian)(dian)流(liu)通過(guo)一個連接(jie)在ILED管(guan)腳(jiao)的(de)(de)外(wai)部(bu)電(dian)(dian)阻(zu)來調(diao)節。RSET管(guan)腳(jiao)被(bei)內部(bu)調(diao)節到(dao)350mV,使(shi)得流(liu)出該(gai)管(guan)腳(jiao)的(de)(de)電(dian)(dian)流(liu)IILED=0.35V/RILED,LED電(dian)(dian)流(liu)控(kong)制電(dian)(dian)路將(jiang)流(liu)入LED管(guan)腳(jiao)的(de)(de)電(dian)(dian)流(liu)ISTR調(diao)節為ISTR=6000×IILED=6000×0.35V/RILED,因此(ci)RILED= 2100/ISTR。本設計中(zhong),紅色管(guan)芯需要20mA電(dian)(dian)流(liu),紅色互補色管(guan)芯需要40mA電(dian)(dian)流(liu),由上述公式可知電(dian)(dian)阻(zu)R11、R4分別選擇105kΩ和52.5kΩ。再通過(guo)輸出電(dian)(dian)流(liu)反(fan)饋環路來調(diao)節PWM占空比,從而使(shi)負載(zai)LED的(de)(de)電(dian)(dian)流(liu)ISTR在穩(wen)態時等于設定(ding)值,從而實(shi)現(xian)了(le)對(dui)輸出電(dian)(dian)流(liu)的(de)(de)控(kong)制,以驅動(dong)不同管(guan)芯的(de)(de)LED負載(zai)。

2.5驅動(dong)芯片與DC-DC反饋(kui)連接方(fang)式

本文(wen)驅動芯片(pian)(pian)(pian)采(cai)用級(ji)聯方式,第一(yi)顆(ke)驅動芯片(pian)(pian)(pian)的FBIN接地,其(qi)FBO與后一(yi)顆(ke)驅動芯片(pian)(pian)(pian)的FBIN相(xiang)連,最后一(yi)顆(ke)驅動芯片(pian)(pian)(pian)的FBO與DC-DC控(kong)(kong)制(zhi)器(qi)(qi)的分壓電(dian)阻相(xiang)連,輸出將反饋引入(ru)外部DC-DC控(kong)(kong)制(zhi)器(qi)(qi),以此來控(kong)(kong)制(zhi)輸出電(dian)壓,以減少加在驅動芯片(pian)(pian)(pian)的電(dian)壓,提(ti)高了系統效(xiao)率(lv)。具(ju)體的MSL3162級(ji)聯方式和FBO與DC-DC分壓電(dian)阻之(zhi)間的連接方式如圖4所(suo)示(shi)。

FBO信(xin)(xin)(xin)號(hao)非常敏感,因此在閑置不(bu)用的情況下,要接地而(er)且要盡可能靠(kao)近(jin)GND,當FBIN/FBO信(xin)(xin)(xin)號(hao)穿過電(dian)(dian)路板時,應縮(suo)短走線長度,如有大(da)電(dian)(dian)流(liu)信(xin)(xin)(xin)號(hao)應盡可能避開反饋信(xin)(xin)(xin)號(hao)或將反饋信(xin)(xin)(xin)號(hao)包(bao)地線,以屏蔽噪聲信(xin)(xin)(xin)號(hao)。FBO輸出反饋電(dian)(dian)流(liu)到外部DC-DC,但一旦MSL3162關斷,FBO不(bu)僅(jin)不(bu)能為電(dian)(dian)源提供驅動(dong)電(dian)(dian)流(liu),反而(er)使DC-DC負載(zai)和輸出電(dian)(dian)壓增(zeng)加,為防止這種情況發生(sheng),在本(ben)設計中將FBO與(yu)DC-DC控制器分壓電(dian)(dian)阻之間接入(ru)肖(xiao)特基(ji)二極管。

2.6各種控制(zhi)信號

FPGA通(tong)過(guo)(guo)SCL、SDA、GSC、PHI接口控(kong)制(zhi)驅動(dong)(dong)(dong)IC,從而控(kong)制(zhi)LED陣列。SDA為(wei)串(chuan)行數(shu)據(ju)(ju)輸(shu)(shu)(shu)入(ru)(ru)/輸(shu)(shu)(shu)出,SCL為(wei)時鐘輸(shu)(shu)(shu)入(ru)(ru),GSC為(wei)FPGA輸(shu)(shu)(shu)入(ru)(ru)到驅動(dong)(dong)(dong)芯片的(de)(de)(de)(de)(de)基(ji)準頻(pin)率,PHI為(wei)調光頻(pin)率,該(gai)驅動(dong)(dong)(dong)芯片采(cai)用I2C協議與前端(duan)的(de)(de)(de)(de)(de)FPGA進(jin)行通(tong)信。具(ju)體工(gong)作過(guo)(guo)程為(wei):系統(tong)上(shang)電后,首先對(dui)MSL3162進(jin)行初始化(hua),驅動(dong)(dong)(dong)芯片的(de)(de)(de)(de)(de)E2PROM數(shu)據(ju)(ju)根據(ju)(ju)初始設定(ding)值自(zi)動(dong)(dong)(dong)寫入(ru)(ru)相應(ying)的(de)(de)(de)(de)(de)寄(ji)(ji)(ji)存(cun)器(qi)(qi),包括輸(shu)(shu)(shu)入(ru)(ru)/輸(shu)(shu)(shu)出端(duan)口定(ding)義、時鐘初始化(hua)以(yi)及定(ding)時器(qi)(qi)和中(zhong)(zhong)斷的(de)(de)(de)(de)(de)初始化(hua)設置,然后由FPGA將提取(qu)的(de)(de)(de)(de)(de)亮(liang)(liang)度信號數(shu)據(ju)(ju)通(tong)過(guo)(guo)I2C接口送至(zhi)MSL3162的(de)(de)(de)(de)(de)內部寄(ji)(ji)(ji)存(cun)器(qi)(qi)。其(qi)中(zhong)(zhong)占(zhan)空比(bi)數(shu)值分別寫入(ru)(ru)寄(ji)(ji)(ji)存(cun)器(qi)(qi)PWM0至(zhi)PWMF,PWM0至(zhi)PWMF為(wei)8位寄(ji)(ji)(ji)存(cun)器(qi)(qi),芯片內置計(ji)(ji)(ji)數(shu)器(qi)(qi),當(dang)來一個(ge)GSC上(shang)升沿即計(ji)(ji)(ji)數(shu)一次(ci),每次(ci)計(ji)(ji)(ji)數(shu)結束后即與寄(ji)(ji)(ji)存(cun)器(qi)(qi)PWM0至(zhi)PWMF內部數(shu)據(ju)(ju)相比(bi)較,若計(ji)(ji)(ji)數(shu)器(qi)(qi)數(shu)據(ju)(ju)小于(yu)寄(ji)(ji)(ji)存(cun)器(qi)(qi)數(shu)據(ju)(ju)則(ze)保持低電平,計(ji)(ji)(ji)數(shu)器(qi)(qi)繼(ji)續(xu)計(ji)(ji)(ji)數(shu),直至(zhi)計(ji)(ji)(ji)數(shu)器(qi)(qi)數(shu)據(ju)(ju)等(deng)于(yu)寄(ji)(ji)(ji)存(cun)器(qi)(qi)數(shu)據(ju)(ju),則(ze)輸(shu)(shu)(shu)出高電平,使(shi)(shi)LED燈串(chuan)關斷,此周期數(shu)據(ju)(ju)輸(shu)(shu)(shu)出完畢后,PHI的(de)(de)(de)(de)(de)電平上(shang)升,使(shi)(shi)整個(ge)驅動(dong)(dong)(dong)芯片復(fu)位,進(jin)入(ru)(ru)下(xia)一周期數(shu)據(ju)(ju)讀取(qu)。FPGA通(tong)過(guo)(guo)寫入(ru)(ru)寄(ji)(ji)(ji)存(cun)器(qi)(qi)的(de)(de)(de)(de)(de)數(shu)值控(kong)制(zhi)LED開(kai)啟的(de)(de)(de)(de)(de)脈(mo)寬,來實現對(dui)每串(chuan)燈的(de)(de)(de)(de)(de)亮(liang)(liang)度控(kong)制(zhi)。

3結論

本文設計了一種寬色域(yu)(yu)、直下式(shi)LED背(bei)光(guang)(guang)(guang)源驅動(dong)電路,針對(dui)所(suo)選取的背(bei)光(guang)(guang)(guang)源特性(xing)(xing),解決了驅動(dong)部分的電路設計,并(bing)在(zai)所(suo)開發的背(bei)光(guang)(guang)(guang)系統(tong)上實(shi)現了PWM調光(guang)(guang)(guang)。實(shi)驗證明,該系統(tong)單通道電流精確可控(kong),光(guang)(guang)(guang)學(xue)效果非常優(you)異,極大提(ti)高了液(ye)晶電視(shi)的色域(yu)(yu)。在(zai)此基礎上,如(ru)何(he)在(zai)保證LED燈的可靠性(xing)(xing)、散熱性(xing)(xing)與(yu)光(guang)(guang)(guang)均勻性(xing)(xing)的前(qian)提(ti)下,降低LED背(bei)光(guang)(guang)(guang)模組的厚度,并(bing)進一步完(wan)善LED動(dong)態背(bei)光(guang)(guang)(guang)控(kong)制算法成為下一步工作的重點,以(yi)使直下式(shi)LED背(bei)光(guang)(guang)(guang)液(ye)晶電視(shi)能(neng)在(zai)顏(yan)色表現力(li)與(yu)超(chao)薄設計方面均有突出(chu)表現。

參考文獻

[1] Martynov Y, Konijn Huub, Pfeffer Nicolo, et al. High-efficiency slim LED backlight system with mixing light guide[J]. SID Symposium Digest, 2003, 43(1): 1259-126.

[2] 王(wang)大(da)巍,王(wang)剛,李俊(jun)峰,劉(liu)敬(jing)偉. 薄(bo)膜晶(jing)(jing)體管液(ye)晶(jing)(jing)顯示(shi)器件的制造、測試與技(ji)術發展[M]. 北京:機械(xie)工業出(chu)版(ban)社.

[3] Seyno Sluyterman. 動(dong)態掃(sao)描(miao)背光使LCD電視呈現活力[J]. 現代顯示,2006,63:18-21.

篇5

Abstract: Through discussion and research on design features of the secondary school building in recent years in Dongguan area, the author hopes to explore a train of thought on campus architecture design which meets the need of secondary schools in Dongguan area, to solve the situation that education idea is suitable for education building under the new era, realizing the sustainable development of the campus, and promoting education buildings develop in a reasonable and sound way.

關鍵詞: 中學校(xiao)園;開(kai)放空(kong)間;嶺南特色

Key words: secondary school campus;open space;characteristics of Lingnan

中(zhong)圖分類號:G63文(wen)獻(xian)標識碼:A文(wen)章編(bian)號:1006-4311(2010)26-0200-01

1建筑(zhu)空間的多樣性

1.1 校(xiao)(xiao)園開(kai)放(fang)空(kong)(kong)間的(de)(de)設(she)計特(te)點眾(zhong)所周知(zhi),校(xiao)(xiao)園活(huo)(huo)力來源于各(ge)種(zhong)交往(wang)(wang)活(huo)(huo)動,校(xiao)(xiao)園開(kai)放(fang)空(kong)(kong)間存在的(de)(de)目的(de)(de)就是為了承載(zai)這些(xie)活(huo)(huo)動。換(huan)言(yan)之,對開(kai)放(fang)空(kong)(kong)間的(de)(de)控制應(ying)從人的(de)(de)使(shi)用要求出發,考慮不同層次的(de)(de)交往(wang)(wang)活(huo)(huo)動的(de)(de)可能性,盡量滿(man)足使(shi)用者對公共與秘(mi)密的(de)(de)不同程度的(de)(de)需(xu)求。東莞(guan)近(jin)幾(ji)年中學(xue)校(xiao)(xiao)園對開(kai)放(fang)空(kong)(kong)間的(de)(de)設(she)計比較注重,有以下幾(ji)個設(she)計內容(rong)及重點(圖1):

1.1.1 校(xiao)(xiao)園(yuan)級開(kai)(kai)放空(kong)間(jian)這一(yi)層次的(de)(de)(de)(de)(de)開(kai)(kai)放空(kong)間(jian)主要包括那(nei)些容納(na)全校(xiao)(xiao)多數師生進(jin)行交往(wang)活動的(de)(de)(de)(de)(de)空(kong)間(jian),如校(xiao)(xiao)園(yuan)入口廣場(chang)(chang)、中心廣場(chang)(chang)、共享(xiang)生態區等。這類開(kai)(kai)放空(kong)間(jian)都是(shi)校(xiao)(xiao)園(yuan)的(de)(de)(de)(de)(de)形象標(biao)志,控制重(zhong)點是(shi)它的(de)(de)(de)(de)(de)尺度(du)、圍合界面、不同(tong)的(de)(de)(de)(de)(de)空(kong)間(jian)限定。校(xiao)(xiao)園(yuan)入口廣場(chang)(chang)歷來(lai)是(shi)我們關注的(de)(de)(de)(de)(de)重(zhong)點,它是(shi)校(xiao)(xiao)園(yuan)面對社(she)會(hui)的(de)(de)(de)(de)(de)第一(yi)個(ge)(ge)“窗口”,是(shi)功能性的(de)(de)(de)(de)(de),是(shi)要解決人流和(he)(he)車輛的(de)(de)(de)(de)(de)集散,同(tong)時也是(shi)禮儀性的(de)(de)(de)(de)(de)人們進(jin)入校(xiao)(xiao)園(yuan)的(de)(de)(de)(de)(de)一(yi)個(ge)(ge)暗示性的(de)(de)(de)(de)(de)心理過渡(du)空(kong)間(jian)。共享(xiang)生態區從性質上說屬(shu)于自(zi)然(ran)(ran)景區,尤其(qi)在工業(ye)化程度(du)高的(de)(de)(de)(de)(de)東莞,生態型和(he)(he)自(zi)然(ran)(ran)性更(geng)加重(zhong)要,可以體現(xian)校(xiao)(xiao)園(yuan)豐富的(de)(de)(de)(de)(de)內涵,加上適(shi)宜的(de)(de)(de)(de)(de)植(zhi)物配置和(he)(he)水的(de)(de)(de)(de)(de)處理方(fang)式,體現(xian)出(chu)嶺南(nan)水鄉的(de)(de)(de)(de)(de)特點。

1.1.2 組(zu)團(tuan)級(ji)開放空(kong)(kong)間(jian)(jian)(jian)組(zu)團(tuan)級(ji)開發空(kong)(kong)間(jian)(jian)(jian),顧名(ming)思義就是建(jian)筑群所合圍(wei)形成(cheng)的(de)空(kong)(kong)間(jian)(jian)(jian)。它(ta)的(de)尺度(du)相(xiang)對于(yu)校園級(ji)開放空(kong)(kong)間(jian)(jian)(jian)要小(xiao),適(shi)合于(yu)中(zhong)小(xiao)型(xing)(xing)集體(ti)活(huo)動(dong)。它(ta)的(de)重點是合理(li)進行(xing)(xing)功能分區,組(zu)織好交(jiao)通流線。這種類型(xing)(xing)的(de)空(kong)(kong)間(jian)(jian)(jian)聯系各個建(jian)筑組(zu)團(tuan),交(jiao)通性質較強,但(dan)同時也能為(wei)人們提(ti)供進行(xing)(xing)交(jiao)往(wang)、休憩(qi)、思考等多種活(huo)動(dong)的(de)場所。

1.1.3 內部級(ji)開放空間(jian)(jian)這(zhe)(zhe)是相對內向的(de)開放空間(jian)(jian),較為安(an)靜(jing)靜(jing)止,主要分布于建(jian)(jian)筑周圍(wei),在體現細節設計(ji)的(de)今天,它的(de)處理(li)也(ye)極其重要,例如建(jian)(jian)筑物入口庭(ting)(ting)院(yuan)、建(jian)(jian)筑內庭(ting)(ting)院(yuan)等。由于使用者對空間(jian)(jian)具有心理(li)認同的(de)勢力范圍(wei),能令(ling)使用者感到歸(gui)屬感和占(zhan)有感,在這(zhe)(zhe)樣的(de)空間(jian)(jian)里更容易發生明顯的(de)交(jiao)往行為,能為使用者創造(zao)輕松、安(an)靜(jing)、適宜(yi)交(jiao)流的(de)空間(jian)(jian)環境。

1.2 架(jia)空(kong)層和(he)連廊(lang)――地(di)面步(bu)行系(xi)統和(he)空(kong)中(zhong)(zhong)(zhong)步(bu)行系(xi)統為提高(gao)效率(lv),方便使用(yong),在(zai)教學區、生(sheng)活(huo)區往往設置(zhi)不少架(jia)空(kong)層及(ji)空(kong)中(zhong)(zhong)(zhong)連廊(lang)。因此架(jia)空(kong)層及(ji)空(kong)中(zhong)(zhong)(zhong)步(bu)行系(xi)統日益成為校園規(gui)劃(hua)設計中(zhong)(zhong)(zhong)重要的一項,且具有(you)一定特殊性。

東莞地區(qu)的(de)(de)中(zhong)學(xue)一般首層(ceng)(ceng)都做成架(jia)空層(ceng)(ceng),使之(zhi)空氣流通較好(hao),也(ye)(ye)不(bu)會有(you)(you)首層(ceng)(ceng)教室(shi)光線(xian)不(bu)足及潮(chao)濕等(deng)問(wen)題。同時,架(jia)空層(ceng)(ceng)也(ye)(ye)是(shi)學(xue)生活(huo)動、交(jiao)往的(de)(de)好(hao)地方,可以成為(wei)有(you)(you)趣(qu)(qu)的(de)(de)交(jiao)往空間(jian)。連廊(lang)在(zai)空間(jian)形態上呈線(xian)形,導(dao)向性明(ming)確(que)。適度引入的(de)(de)光線(xian)和宜人的(de)(de)尺度會讓本來僅是(shi)單(dan)調線(xian)性導(dao)向的(de)(de)“通道(dao)”空間(jian)具有(you)(you)促進偶然交(jiao)往的(de)(de)品質,這樣的(de)(de)品質可以由墻報、休息椅、欄桿等(deng)設(she)施(shi)來獲得。同時,建筑間(jian)的(de)(de)連廊(lang)還是(shi)解決建筑空間(jian)轉換的(de)(de)有(you)(you)效(xiao)方法,也(ye)(ye)可成為(wei)建筑空間(jian)的(de)(de)趣(qu)(qu)味點所(suo)在(zai)。架(jia)空層(ceng)(ceng)及連廊(lang)作為(wei)地面步行(xing)系統(tong)和空中(zhong)步行(xing)系統(tong)的(de)(de)重要元素(su),在(zai)東莞地區(qu)中(zhong)學(xue)校園規劃中(zhong)的(de)(de)地位極(ji)其重要,設(she)計者需(xu)要合理布置(zhi)架(jia)空層(ceng)(ceng)及連廊(lang),使之(zhi)達到錦(jin)上添(tian)花(hua)的(de)(de)作用。

2建筑(zhu)風格及細部處理

2.1 建(jian)(jian)筑風(feng)格(ge)總體(ti)而言,東莞(guan)(guan)近(jin)(jin)幾年的(de)中學校園(yuan)(yuan)設(she)(she)計(ji)(ji)(ji)呈現(xian)出(chu)(chu)中國(guo)古典風(feng)格(ge)與現(xian)代簡約風(feng)格(ge)交融的(de)設(she)(she)計(ji)(ji)(ji)思路。具體(ti)到東莞(guan)(guan)地(di)區(qu)就是對嶺(ling)(ling)南園(yuan)(yuan)林建(jian)(jian)筑設(she)(she)計(ji)(ji)(ji)加(jia)以提煉及發揚。嶺(ling)(ling)南建(jian)(jian)筑非常注意(yi)通過庭(ting)院、天井等院落式的(de)布局形(xing)成一(yi)種活動空(kong)間(jian),達到庭(ting)院與山水的(de)有機結合(he)。東莞(guan)(guan)近(jin)(jin)幾年的(de)中學校園(yuan)(yuan)設(she)(she)計(ji)(ji)(ji)充分吸取了嶺(ling)(ling)南地(di)區(qu)的(de)建(jian)(jian)筑特點,對嶺(ling)(ling)南園(yuan)(yuan)林的(de)精(jing)(jing)髓進行提煉,結合(he)現(xian)代建(jian)(jian)筑設(she)(she)計(ji)(ji)(ji)理念,營造(zao)出(chu)(chu)具有相對自由開(kai)放、強烈水鄉文化感染力的(de)共(gong)享空(kong)間(jian)。近(jin)(jin)幾年東莞(guan)(guan)地(di)區(qu)的(de)中學校園(yuan)(yuan)設(she)(she)計(ji)(ji)(ji)很好地(di)體(ti)現(xian)了嶺(ling)(ling)南園(yuan)(yuan)林通透、小巧、精(jing)(jing)致的(de)設(she)(she)計(ji)(ji)(ji)精(jing)(jing)神,營造(zao)出(chu)(chu)舒適的(de)廣場及精(jing)(jing)致的(de)中庭(ting)空(kong)間(jian),同時水的(de)運用大大提高(gao)了共(gong)享空(kong)間(jian)的(de)環境質量(liang),為校園(yuan)(yuan)的(de)使(shi)用者提供出(chu)(chu)一(yi)個(ge)安靜、精(jing)(jing)致、高(gao)雅的(de)學習環境。

2.2 建(jian)筑(zhu)細(xi)(xi)部(bu)(bu)處理(li)(li)所謂(wei)的“細(xi)(xi)部(bu)(bu)”應該是(shi)以小見大的地(di)方,每(mei)個學校的細(xi)(xi)部(bu)(bu)處理(li)(li)有很多類型(xing),但是(shi)每(mei)個細(xi)(xi)部(bu)(bu)是(shi)否做得“得當”,成為(wei)設(she)計成功(gong)的關鍵因(yin)素。下(xia)面(mian)的圖片為(wei)近(jin)幾年東莞地(di)區中學校園(yuan)細(xi)(xi)部(bu)(bu)的處理(li)(li)手(shou)法(fa),從中可(ke)以看到其細(xi)(xi)部(bu)(bu)處理(li)(li)的特色。

①嶺南園林(lin)的通透空間與(yu)現代的灰空間處(chu)理(圖2)。②嶺南傳(chuan)統(tong)建筑元素和符號與(yu)現代建筑材料的結合(圖3)。③嶺南地區氣候特(te)點與(yu)細部處(chu)理(圖4)。

不同的(de)(de)(de)(de)細部風格會呈現不同的(de)(de)(de)(de)建筑特(te)點,設計出(chu)古典(dian)符號并不難,但更重要的(de)(de)(de)(de)是(shi)它的(de)(de)(de)(de)內涵,真正一個好的(de)(de)(de)(de)建筑不單是(shi)在乎(hu)它的(de)(de)(de)(de)形式如何,更主要的(de)(de)(de)(de)是(shi)它表現的(de)(de)(de)(de)思(si)想,好的(de)(de)(de)(de)建筑也是(shi)有思(si)想的(de)(de)(de)(de),是(shi)會說話的(de)(de)(de)(de),它體現一種文化(hua)的(de)(de)(de)(de)內涵。

3結語

本章通(tong)過(guo)對東莞(guan)地(di)區近年來中學校園建筑(zhu)設(she)(she)計特(te)點的(de)介紹(shao),指出了(le)東莞(guan)地(di)區中學校園的(de)建筑(zhu)設(she)(she)計在各(ge)方面的(de)特(te)點,并闡述了(le)其背后的(de)設(she)(she)計理念,希望(wang)能(neng)對東莞(guan)地(di)區中學校園設(she)(she)計的(de)思路有所幫助(zhu)。

參考文獻:

[1]林玉(yu)蓮,胡正凡.環境心理學.中國(guo)建(jian)筑工業(ye)出版社,2006,8,第二版.

篇6

關(guan)鍵詞:山(shan)區(qu);化工園;道路(lu);設計;路(lu)基(ji)處理(li)。

Abstract: Through the summary of the experience of planning, design and costruction of the road network project in the eastern chemical industrial park of Zibo city, this paper analyzes the design points of the road network planning, road flat, longitudinal design, subgrade treatment and pipeline design and coordination when construct a large-scale chemical industrial park in the mountainous area.

Key words: mountain area; chemical industrial park; road; design; subgrade treatment.

中(zhong)圖分類(lei)號(hao):U212.1文獻標識碼:A

1概述

1.1項目背景

作為(wei)傳統工礦城(cheng)市(shi),化學醫藥(yao)工業在(zai)淄博(bo)經濟發展中發揮(hui)了(le)重要作用(yong)。隨著城(cheng)市(shi)化進程加(jia)快,原本位于城(cheng)郊的一些企(qi)業被圍困在(zai)了(le)市(shi)中心。企(qi)業生產(chan)(chan)過程中產(chan)(chan)生的污水、氣味和噪音,對城(cheng)區居民生活造(zao)成嚴重影響。

為(wei)著力打造(zao)生態、和(he)(he)諧、宜居的(de)現代化(hua)區(qu)(qu)(qu)域(yu)中(zhong)心城市,推動(dong)淄博化(hua)工產(chan)業布(bu)局結構的(de)戰略性(xing)調整(zheng),2009年初,淄博市委、市政府確定,對(dui)老(lao)城區(qu)(qu)(qu)內所屬(shu)化(hua)工企(qi)業進行整(zheng)體搬遷改造(zao),利(li)用三年左右的(de)時間,基本(ben)完成淄博東部化(hua)工園區(qu)(qu)(qu)產(chan)業布(bu)局調整(zheng)。園區(qu)(qu)(qu)定位于(yu)以醫藥(yao)原料藥(yao)產(chan)品和(he)(he)精(jing)細(xi)化(hua)工產(chan)品為(wei)主的(de)特色(se)精(jing)細(xi)化(hua)工園區(qu)(qu)(qu),園區(qu)(qu)(qu)的(de)建(jian)設(she)(she)是市委市政府為(wei)深入貫(guan)徹落(luo)實科(ke)學發展觀(guan),加快(kuai)推進產(chan)業結構調整(zheng)做出(chu)的(de)重大戰略部署,是促進產(chan)業布(bu)局與城市建(jian)設(she)(she)、生態建(jian)設(she)(she)相和(he)(he)諧的(de)一項重大的(de)舉措。

1.2工程概述

在市發改委的牽頭下,市、區各(ge)(ge)相關部門及省(sheng)內外(wai)專家深入調查研究,廣(guang)泛聽取意見(jian),綜合考(kao)慮各(ge)(ge)種因素(su),最(zui)終確定的園區搬(ban)遷新址距中心城(cheng)區12公(gong)里,遠離居民生活區,緊鄰102省(sheng)道和309國道,運輸便利,發展空間廣(guang)闊,不僅有利于搬(ban)遷企業(ye)長遠發展,也(ye)能吸引(yin)新的關聯企業(ye)入園。

園(yuan)區(qu)(qu)(qu)建設以(yi)政府為(wei)主導、企(qi)業為(wei)主體的原則(ze),化(hua)(hua)工園(yuan)區(qu)(qu)(qu)的基礎設施建設全部由政府承擔,政府負責做好園(yuan)區(qu)(qu)(qu)內(nei)水(shui)、電、路等“七(qi)通一(yi)(yi)平(ping)”,企(qi)業只(zhi)負責自家(jia)廠(chang)區(qu)(qu)(qu)建設。新園(yuan)區(qu)(qu)(qu)占地約10平(ping)方公里,而此園(yuan)區(qu)(qu)(qu)一(yi)(yi)旦與東(dong)臨(lin)規劃面(mian)積42平(ping)方公里的齊(qi)魯化(hua)(hua)工區(qu)(qu)(qu)聯(lian)接成片,未來淄博東(dong)部化(hua)(hua)工區(qu)(qu)(qu)將超過南京(jing)、上海等石化(hua)(hua)強(qiang)市的園(yuan)區(qu)(qu)(qu)面(mian)積。一(yi)(yi)個(ge)現代化(hua)(hua)的大型化(hua)(hua)工園(yuan)區(qu)(qu)(qu)展(zhan)現在人(ren)們(men)面(mian)前。

1.3自(zi)然(ran)與水文地質(zhi)條件

擬建項目地(di)(di)(di)處山(shan)東省(sheng)中部(bu)(bu)、淄博市東部(bu)(bu),位于山(shan)東半島(dao)魯北(bei)(bei)山(shan)地(di)(di)(di)的北(bei)(bei)緣部(bu)(bu)位,地(di)(di)(di)貌類型較(jiao)為(wei)復雜,主要(yao)為(wei)低山(shan)丘陵及山(shan)前平原,上部(bu)(bu)覆蓋第四(si)系沖(chong)積(ji)、洪(hong)積(ji)物(wu),主要(yao)由沖(chong)洪(hong)積(ji)成因(yin)的粘性土組成,基(ji)巖(yan)地(di)(di)(di)層為(wei)奧陶系石(shi)灰巖(yan)。整個園區地(di)(di)(di)形(xing)大致呈南、北(bei)(bei)高(gao),中間部(bu)(bu)位低,地(di)(di)(di)勢起(qi)伏較(jiao)大(區域內自然地(di)(di)(di)形(xing)高(gao)差約120m),土層厚度變(bian)化較(jiao)大,屬山(shan)區地(di)(di)(di)形(xing)。

2道路工程設(she)計(ji)技術(shu)要點

由于本園區(qu)產業(ye)屬性(xing)(xing)(xing)的(de)(de)(de)特殊性(xing)(xing)(xing),所處山(shan)區(qu)地理(li)環境(jing)的(de)(de)(de)復雜性(xing)(xing)(xing),使得該區(qu)路(lu)網設計時(shi)既具(ju)(ju)有(you)一(yi)般工(gong)(gong)業(ye)園區(qu)的(de)(de)(de)交通(tong)特點(dian),同(tong)時(shi)也具(ju)(ju)有(you)山(shan)區(qu)道(dao)路(lu)的(de)(de)(de)工(gong)(gong)程特點(dian)。區(qu)別于一(yi)般平(ping)(ping)原城(cheng)區(qu)內工(gong)(gong)業(ye)園區(qu)路(lu)網規劃設計的(de)(de)(de)主次干道(dao)優化布局、路(lu)線平(ping)(ping)面(mian)(mian)選線比選、道(dao)路(lu)橫斷面(mian)(mian)規劃設計等內容以外,主要設計要點(dian)體現以下幾個方(fang)面(mian)(mian)。

2.1園區路網(wang)規劃(hua)的豎向(xiang)規劃(hua)

路網(wang)豎向(xiang)(xiang)規(gui)(gui)劃(hua)(hua)是(shi)整個園區(qu)路網(wang)規(gui)(gui)劃(hua)(hua)設計(ji)中的(de)重要部分(fen),尤(you)其對處在(zai)山區(qu)地形內(nei)的(de)園區(qu)路網(wang)設計(ji)更顯得尤(you)為突出。沒有一個科學(xue)合理完善(shan)的(de)路網(wang)豎向(xiang)(xiang)規(gui)(gui)劃(hua)(hua),具體(ti)某條道路的(de)合理縱斷(duan)設計(ji)就無(wu)從談(tan)起(qi),相交(jiao)道路豎向(xiang)(xiang)設計(ji)之間也(ye)不能(neng)(neng)較好協調,周(zhou)邊規(gui)(gui)劃(hua)(hua)地塊的(de)豎向(xiang)(xiang)設計(ji)也(ye)不能(neng)(neng)達到最佳優化(hua)。可以說(shuo),路網(wang)豎向(xiang)(xiang)規(gui)(gui)劃(hua)(hua)更是(shi)直接影響(xiang)整個園區(qu)項目的(de)工程建設投(tou)資和運行功(gong)能(neng)(neng)。

在(zai)山區(qu)地形下(xia),路網豎(shu)向規劃時需特別注(zhu)意以下(xia)幾個方面的問題:

(1)掌(zhang)握(wo)清楚各道路沿線(xian)(xian)的(de)(de)地(di)(di)形地(di)(di)勢、地(di)(di)質(zhi)情(qing)況,縱斷設計時盡(jin)可能(neng)地(di)(di)避免大的(de)(de)填方和挖方,盡(jin)可能(neng)地(di)(di)減小(xiao)和平衡路線(xian)(xian)全(quan)段的(de)(de)土石方量,盡(jin)可能(neng)地(di)(di)避開特殊困難(nan)地(di)(di)質(zhi)結構,得到較穩定(ding)的(de)(de)地(di)(di)基環境(jing)。

(2)注(zhu)意相(xiang)交(jiao)道路(lu)(lu)縱(zong)斷設計上的(de)(de)相(xiang)互銜(xian)接,不(bu)要過分保全某(mou)條(tiao)(tiao)路(lu)(lu)線的(de)(de)線形從而忽略了與其相(xiang)交(jiao)的(de)(de)其他道路(lu)(lu)豎向條(tiao)(tiao)件,路(lu)(lu)網(wang)內各路(lu)(lu)線縱(zong)斷條(tiao)(tiao)件應(ying)盡量協調互補。

(3)注意(yi)交叉口前后一段(duan)距(ju)離內(nei)的(de)縱斷坡度不(bu)要(yao)過(guo)大,盡(jin)量不(bu)要(yao)突(tu)破3%,主要(yao)交通(tong)干道路段(duan)縱坡不(bu)要(yao)超(chao)過(guo)5%,否則極不(bu)利于雨雪(xue)天氣時機(ji)動(dong)(dong)車尤其是貨(huo)運車輛的(de)啟動(dong)(dong)、制動(dong)(dong)及通(tong)行。

(4)要特別注意路線周邊(bian)地(di)塊大(da)環境內的平(ping)均自然高程及其(qi)(qi)規(gui)劃高程,注意盡(jin)可(ke)(ke)能地(di)與其(qi)(qi)協調順接,路段局部可(ke)(ke)適當增(zeng)加(jia)填(挖)方(fang)工程量,以減少周邊(bian)用地(di)場平(ping)時的土方(fang)量,最(zui)終(zhong)有(you)利整個園(yuan)區開發(fa)建設。

(5)注意(yi)與管線專業對接,根據(ju)自然地(di)形地(di)勢(shi)特點及管網布局規(gui)劃(hua)設計,盡(jin)量與雨水排(pai)向統一(yi)協調充(chong)分利用道路縱(zong)坡設計,更(geng)加(jia)有利匯(hui)水和排(pai)水。

2.2路(lu)線平面設計(ji)

(1)條件允許時,應盡可(ke)能的采用較大半徑,不(bu)(bu)能過分遷就地形條件而使用短而頻繁的曲(qu)線(xian)。關(guan)于緩和曲(qu)線(xian)的取(qu)值長(chang)(chang)度確定(ding),除(chu)了(le)參考規范(fan)里數(shu)值,建(jian)議其與圓曲(qu)線(xian)的長(chang)(chang)度比(bi)例關(guan)系為(wei)1:1:1;至于其最(zui)大最(zui)小長(chang)(chang)度的規定(ding),考慮小于3s車(che)程(cheng)時駕(jia)駛員反應不(bu)(bu)及(ji),大于10s車(che)程(cheng)駕(jia)駛員需(xu)不(bu)(bu)斷(duan)調整(zheng)方向(xiang)盤易(yi)造成(cheng)疲勞(lao)心燥,故控制(zhi)平曲(qu)線(xian)內(nei)緩和曲(qu)線(xian)長(chang)(chang)度在該路段設計車(che)速的3s~10s車(che)程(cheng)之間。

(2)對于小半徑曲線要合理(li)設置內側加(jia)寬車(che)道以(yi)及合理(li)確定(ding)超(chao)(chao)高(gao)值、超(chao)(chao)高(gao)緩和段。關于確定(ding)超(chao)(chao)高(gao)值i時(shi),不要盲目選取規范要求的下限(xian)(xian)或上限(xian)(xian),而應(ying)該(gai)根(gen)據(ju)具體路(lu)段實際(ji)運(yun)行車(che)速、橫向摩阻(zu)系數的關系來從分(fen)析抗滑移、抗傾覆方面(mian)驗(yan)算、推算才更有針(zhen)對性和實際(ji)意義。

(3)當開(kai)挖上邊坡和加寬(kuan)外側(ce)路基(ji)(ji)兩者工程(cheng)量(liang)相差不多時,應盡可能選(xuan)用開(kai)挖上邊坡方案,防(fang)止(zhi)因新老路基(ji)(ji)的不均勻沉降導致路面交(jiao)界(jie)處產生縱向裂縫。

2.3路(lu)線(xian)縱斷設計

(1)具(ju)體到某道(dao)路的縱(zong)斷設計,在路網豎向規(gui)劃階段的原則仍需(xu)貫(guan)徹。

(2)要特別注意平、縱曲線的相互協調。條件困難達(da)不到協調時,竟可(ke)能改善縱向(xiang)的線形(xing)條件。

(3)要特別重視(shi)路(lu)(lu)線范圍內的工程地(di)質勘察,合理避(bi)讓及有針對性(xing)的處理不良地(di)質,可(ke)通(tong)過縱斷高(gao)程設(she)計(ji),有針對性(xing)地(di)控制道路(lu)(lu)路(lu)(lu)床部分的位置坐于某一深度范圍(例如(ru)較穩(wen)(wen)定(ding)的原狀土層內或(huo)(huo)原狀基巖之上),已(yi)得到較為穩(wen)(wen)定(ding)或(huo)(huo)便于處理的地(di)基環境(jing),大大提高(gao)路(lu)(lu)基穩(wen)(wen)定(ding)性(xing)條件。

(4)注(zhu)意避(bi)免出現(xian)長大坡直線(xian),注(zhu)意保證緩坡段的設計。

(5)要特別注意對(dui)已確定高(gao)程的橋(qiao)涵、障礙物及重要構筑物高(gao)程控制順接。

(6)注意結(jie)合(he)雨、污水(shui)等重力流管線(xian)設(she)(she)計(ji),合(he)理(li)設(she)(she)計(ji)路(lu)段(duan)的最低收(shou)水(shui)點和最高分水(shui)嶺。

2.4路基設計

篇7

關鍵詞(ci) LED 驅動電源 LED燈(deng) 發展趨勢

中圖分類號:TM923 文(wen)獻標識碼(ma):A

1 LED驅動電源定義

LED驅(qu)動(dong)(dong)電(dian)源把電(dian)源供應轉(zhuan)換(huan)為特定的(de)電(dian)壓(ya)(ya)(ya)(ya)(ya)電(dian)流(liu)以驅(qu)動(dong)(dong)LED發光的(de)電(dian)壓(ya)(ya)(ya)(ya)(ya)轉(zhuan)換(huan)器(qi)(qi)(qi),通常情況(kuang)下,LED驅(qu)動(dong)(dong)電(dian)源的(de)輸(shu)(shu)入(ru)包(bao)(bao)括高(gao)(gao)壓(ya)(ya)(ya)(ya)(ya)工頻交流(liu)(即市電(dian))、低壓(ya)(ya)(ya)(ya)(ya)直流(liu)、高(gao)(gao)壓(ya)(ya)(ya)(ya)(ya)直流(liu)、低壓(ya)(ya)(ya)(ya)(ya)高(gao)(gao)頻交流(liu)(如電(dian)子變壓(ya)(ya)(ya)(ya)(ya)器(qi)(qi)(qi)的(de)輸(shu)(shu)出)等。而LED驅(qu)動(dong)(dong)電(dian)源的(de)輸(shu)(shu)出則(ze)大多數為可隨LED正(zheng)向壓(ya)(ya)(ya)(ya)(ya)降值變化(hua)而改變電(dian)壓(ya)(ya)(ya)(ya)(ya)的(de)恒定電(dian)流(liu)源。LED電(dian)源核心元(yuan)件(jian)包(bao)(bao)括開關(guan)(guan)控制(zhi)器(qi)(qi)(qi)、電(dian)感(gan)器(qi)(qi)(qi)、開關(guan)(guan)元(yuan)器(qi)(qi)(qi)件(jian)(MOSfet)、反饋電(dian)阻、輸(shu)(shu)入(ru)濾波器(qi)(qi)(qi)件(jian)、輸(shu)(shu)出濾波器(qi)(qi)(qi)件(jian)等等。根據不同場合要求,還要有輸(shu)(shu)入(ru)過壓(ya)(ya)(ya)(ya)(ya)保(bao)護電(dian)路、輸(shu)(shu)入(ru)欠(qian)壓(ya)(ya)(ya)(ya)(ya)保(bao)護電(dian)路,LED開路保(bao)護、過流(liu)保(bao)護等電(dian)路。

2 LED驅動電(dian)源研(yan)究現狀

從LED驅動(dong)器供電(dian)可以將其分成(cheng)DC/DC和AC/DC兩類。DC/DC驅動(dong)器一般由電(dian)池(chi)、電(dian)瓶或穩壓(ya)電(dian)源供電(dian),主(zhu)要(yao)用(yong)于便攜式(shi)電(dian)子產(chan)品、礦燈、汽車等用(yong)電(dian)設備。AC/DC驅動(dong)器直(zhi)接(jie)由市電(dian)供電(dian),現階段主(zhu)要(yao)用(yong)于裝飾,景(jing)觀照明的LED燈。當前,DC/DC驅動(dong)器主(zhu)要(yao)有兩種設計方案(an):電(dian)容式(shi)電(dian)荷(he)泵電(dian)路(lu)和電(dian)感(gan)式(shi)DC/DC電(dian)路(lu)。AC/DC驅動(dong)器有工頻(pin)變壓(ya)降壓(ya),電(dian)容降壓(ya),buck降壓(ya)電(dian)路(lu)以及單片開(kai)關電(dian)路(lu)幾(ji)個(ge)設計方案(an)。

3 LED燈照明的優點

與(yu)現行照(zhao)明設備比較,LED照(zhao)明有(you)眾多(duo)突出優點。①發光(guang)(guang)(guang)(guang)效率高(gao),耗能少,LED的(de)(de)(de)光(guang)(guang)(guang)(guang)效預計可(ke)達(da)到200lm/W以上(shang),而(er)且光(guang)(guang)(guang)(guang)的(de)(de)(de)單色性(xing)好(hao)、光(guang)(guang)(guang)(guang)譜窄。在同樣的(de)(de)(de)照(zhao)明效果下,LED的(de)(de)(de)耗電量是白(bai)(bai)熾燈泡的(de)(de)(de)八分(fen)之一,熒光(guang)(guang)(guang)(guang)燈管(guan)的(de)(de)(de)二(er)分(fen)之一。②使用壽(shou)命(ming)長,LED的(de)(de)(de)使用壽(shou)命(ming)可(ke)以長達(da)近十(shi)萬小(xiao)時(shi)(shi),而(er)白(bai)(bai)熾燈一般為(wei)1000~2000小(xiao)時(shi)(shi),熒光(guang)(guang)(guang)(guang)燈為(wei)6000~8000小(xiao)時(shi)(shi)。③安全(quan)環保,LED為(wei)全(quan)固態發光(guang)(guang)(guang)(guang)體,耐震、耐沖擊,而(er)且發熱量低,無熱輻射(she),無污染。④啟(qi)動時(shi)(shi)間(jian)短,LED的(de)(de)(de)響應時(shi)(shi)間(jian)只有(you)幾(ji)十(shi)納秒(miao),因(yin)此適合用在一些需(xu)要(yao)快速響應的(de)(de)(de)場合。⑤體積小(xiao),LED具有(you)小(xiao)型化、平面化、可(ke)設計性(xing)強的(de)(de)(de)特點,可(ke)以使我們(men)從傳統(tong)的(de)(de)(de)點、線光(guang)(guang)(guang)(guang)源局限中解放出來,實(shi)現照(zhao)明的(de)(de)(de)隨(sui)意布置。

4 LED電源和驅動電路(lu)主(zhu)要技術概況

4.1電壓變換技術

電(dian)(dian)(dian)源(yuan)(yuan)是影(ying)響LED光源(yuan)(yuan)可靠性和適應性的(de)(de)一個重要組成部分,必須作(zuo)重點考慮。目前我國的(de)(de)市電(dian)(dian)(dian)是220V的(de)(de)交流(liu)電(dian)(dian)(dian),而LED光源(yuan)(yuan)屬半導體光源(yuan)(yuan),通常是用直流(liu)低(di)電(dian)(dian)(dian)壓供電(dian)(dian)(dian),這(zhe)就要求在這(zhe)些燈(deng)具(ju)中(zhong)或外部設置AC-DC轉換電(dian)(dian)(dian)路,以(yi)適應LED電(dian)(dian)(dian)流(liu)驅動的(de)(de)特征。目前電(dian)(dian)(dian)源(yuan)(yuan)選擇的(de)(de)途徑有開關電(dian)(dian)(dian)源(yuan)(yuan)、高(gao)頻(pin)電(dian)(dian)(dian)源(yuan)(yuan)、電(dian)(dian)(dian)容(rong)降壓后整流(liu)電(dian)(dian)(dian)源(yuan)(yuan)等多種,根據電(dian)(dian)(dian)流(liu)穩定(ding)性,瞬態過沖以(yi)及安全性、可靠性的(de)(de)不同(tong)要求作(zuo)不同(tong)選擇。

4.2電源與驅(qu)動電路的壽命(ming)與成本

LED壽(shou)(shou)命(ming)(ming)方面,雖然單(dan)顆LED本(ben)身的(de)壽(shou)(shou)命(ming)(ming)長達(da)(da)10萬小時(shi),但其(qi)應用(yong)時(shi)必(bi)須(xu)搭配(pei)電(dian)(dian)(dian)源轉換電(dian)(dian)(dian)路(lu)(lu),故LED照(zhao)明(ming)(ming)(ming)器具(ju)整(zheng)體(ti)壽(shou)(shou)命(ming)(ming)必(bi)須(xu)從光電(dian)(dian)(dian)整(zheng)合應用(yong)加(jia)以(yi)考慮(lv)。但對(dui)照(zhao)明(ming)(ming)(ming)用(yong)LED,為達(da)(da)到(dao)匹配(pei)要求,電(dian)(dian)(dian)源與驅(qu)(qu)動電(dian)(dian)(dian)路(lu)(lu)的(de)壽(shou)(shou)命(ming)(ming)必(bi)須(xu)超(chao)(chao)過10萬小時(shi),使(shi)其(qi)不再成(cheng)為LED照(zhao)明(ming)(ming)(ming)系(xi)統的(de)瓶(ping)頸因(yin)素。在考慮(lv)長壽(shou)(shou)命(ming)(ming)的(de)同(tong)時(shi)又不能增加(jia)太多的(de)成(cheng)本(ben),電(dian)(dian)(dian)源與驅(qu)(qu)動電(dian)(dian)(dian)路(lu)(lu)的(de)壽(shou)(shou)命(ming)(ming)與成(cheng)本(ben)的(de)通常不宜超(chao)(chao)過照(zhao)明(ming)(ming)(ming)系(xi)統總成(cheng)本(ben)的(de)三(san)分之一,在LED照(zhao)明(ming)(ming)(ming)燈具(ju)產品(pin)發(fa)展的(de)初期,必(bi)須(xu)平衡(heng)好電(dian)(dian)(dian)源與驅(qu)(qu)動電(dian)(dian)(dian)路(lu)(lu)的(de)壽(shou)(shou)命(ming)(ming)與成(cheng)本(ben)的(de)關系(xi)。

4.3驅動程序的可編程技術(shu)

LED用作光(guang)(guang)源(yuan)的(de)(de)一(yi)個顯著(zhu)特點就是在低驅動電流條件下(xia)仍能(neng)維持其流明(ming)效(xiao)率,同時(shi)對(dui)于R.G.B.多晶型混光(guang)(guang)而形成白光(guang)(guang)來說,通過開發一(yi)種針對(dui)LED的(de)(de)數字(zi)RGB混合控(kong)制(zhi)系統,使用戶能(neng)夠(gou)在很大范(fan)圍內對(dui)LED的(de)(de)亮度(du),顏色(se)(se)和色(se)(se)調進行任意(yi)調節,給人以(yi)一(yi)種全(quan)新的(de)(de)視(shi)覺(jue)享(xiang)受。在城市景觀亮化(hua)(hua)應用方(fang)面,LED光(guang)(guang)源(yuan)可在微處理器控(kong)制(zhi)下(xia)可以(yi)按不(bu)同模式(shi)加以(yi)變化(hua)(hua),形成夜晚的(de)(de)多姿(zi)百(bai)態的(de)(de)動態效(xiao)果,在這方(fang)面將體現LED相對(dui)于其它光(guang)(guang)源(yuan)所具有(you)的(de)(de)獨特的(de)(de)競爭(zheng)優勢(shi)。

4.4電源(yuan)與驅動電路的效率

LED電(dian)(dian)源與驅動電(dian)(dian)路,既要(yao)有一定的供LED所(suo)需的接近恒流的正向電(dian)(dian)流輸(shu)出,又要(yao)有較高的轉換效(xiao)率(lv),電(dian)(dian)光轉化效(xiao)率(lv)是led照明的一個重(zhong)要(yao)因素,否(fou)則就會失去LED節能的優點,目前商(shang)業化的開關電(dian)(dian)源其效(xiao)率(lv)約為(wei)80%左右,作為(wei)led照明用電(dian)(dian)源,其轉換效(xiao)率(lv)仍須進一步提升(sheng)。

5 LED驅動(dong)電源發展趨勢

LED由(you)于在經濟環保(bao)、壽命時間(jian)長、光電轉化效率高等眾(zhong)多優點,今(jin)年來在各行(xing)各業的(de)(de)(de)應用得以(yi)快速發展和研究,LED的(de)(de)(de)驅動(dong)電源也成了最近的(de)(de)(de)關注熱(re)點。但由(you)于驅動(dong)電源的(de)(de)(de)設計及驅動(dong)方式選擇不(bu)當,使得LED燈極(ji)易(yi)損壞。未來LED驅動(dong)電源的(de)(de)(de)發展方向為先恒壓,再線(xian)性恒流整合方式。

參考文獻

[1] 蔣天堂.LED的特性及驅動電源(yuan)的發展趨勢[J].照明工程學報(bao),2011,22(3).

[2] 陳(chen)鵬.大功率全(quan)彩色LED驅動電路的研制(zhi)[D].江西師范(fan)大學(xue),2009.

篇8

關鍵詞:關鍵詞:屏蔽門;電源;UPS;蓄(xu)電池

中圖(tu)分(fen)類(lei)號:TP39    文獻標(biao)識碼:A     文章編號:

1.概況

    地鐵(tie)屏蔽門(men)是一項集建筑、機械、材料、電子和信息等學科于一體的(de)(de)(de)(de)高科技產品,屏蔽門(men)系(xi)統是將站(zhan)臺和列車(che)運行區域隔開,通過控(kong)制系(xi)統控(kong)制其(qi)自動開啟,可(ke)有(you)效(xiao)地減(jian)少(shao)空(kong)氣對(dui)流(liu)造成的(de)(de)(de)(de)站(zhan)臺冷熱(re)氣的(de)(de)(de)(de)流(liu)失,保障乘客(ke)進出車(che)廂時(shi)的(de)(de)(de)(de)絕對(dui)安全,降(jiang)(jiang)低列車(che)運行產生的(de)(de)(de)(de)噪(zao)音對(dui)車(che)站(zhan)的(de)(de)(de)(de)影響,為乘客(ke)提供舒適(shi)安全的(de)(de)(de)(de)候車(che)環境,具有(you)節能(neng)、安全、環保、美(mei)觀等功(gong)能(neng)。根據專(zhuan)家測(ce)算,可(ke)以使空(kong)調設備的(de)(de)(de)(de)冷負(fu)荷減(jian)少(shao)35%以上(shang),環控(kong)機房的(de)(de)(de)(de)建筑面積減(jian)少(shao)50%,空(kong)調電耗降(jiang)(jiang)低30%,現已廣泛使于地鐵(tie)站(zhan)臺。

2. 屏蔽(bi)門系統后備電源問題的引出

    屏(ping)蔽(bi)門系(xi)(xi)統(tong)的(de)正常運營與(yu)否直接關系(xi)(xi)到(dao)地(di)鐵運營的(de)服務水平和(he)乘(cheng)客安全,要求在(zai)正常供(gong)電(dian)(dian)系(xi)(xi)統(tong)故(gu)障或車輛在(zai)區間(jian)(jian)阻塞或區間(jian)(jian)發生火災時(shi),屏(ping)蔽(bi)門系(xi)(xi)統(tong)必須能使處于地(di)鐵區間(jian)(jian)的(de)司乘(cheng)人員能順利通(tong)過屏(ping)蔽(bi)門進入站(zhan)(zhan)(zhan)臺(tai)、站(zhan)(zhan)(zhan)廳疏散到(dao)地(di)面的(de)安全區域,故(gu)屏(ping)蔽(bi)門系(xi)(xi)統(tong)的(de)用電(dian)(dian)負(fu)荷可納入特(te)別重要負(fu)荷。根據(ju)《供(gong)配(pei)(pei)電(dian)(dian)系(xi)(xi)統(tong)設計(ji)(ji)規(gui)范》(GB50052-95)要求,對(dui)于特(te)別重要負(fu)荷必須采用一級負(fu)荷供(gong)電(dian)(dian),即(ji)輸入電(dian)(dian)源(yuan)(yuan)(yuan)應(ying)為(wei)兩(liang)路相(xiang)互獨(du)立的(de)三相(xiang)AC380V/50Hz電(dian)(dian)源(yuan)(yuan)(yuan),同(tong)時(shi)還需配(pei)(pei)備(bei)第(di)三電(dian)(dian)源(yuan)(yuan)(yuan),故(gu)國內所有地(di)鐵工程(cheng)的(de)屏(ping)蔽(bi)門系(xi)(xi)統(tong)都(dou)配(pei)(pei)備(bei)了(le)蓄電(dian)(dian)池作(zuo)為(wei)第(di)三電(dian)(dian)源(yuan)(yuan)(yuan)。因此,在(zai)《地(di)鐵設計(ji)(ji)規(gui)范》(GB50157-2003)和(he)《城市軌道交通(tong)站(zhan)(zhan)(zhan)臺(tai)屏(ping)蔽(bi)門》(CJ/T236-2006)中對(dui)后備(bei)電(dian)(dian)源(yuan)(yuan)(yuan)都(dou)作(zuo)了(le)明確(que)規(gui)定:

    《地(di)鐵(tie)設計規范》規定:當屏(ping)蔽門的驅動裝(zhuang)置采用電(dian)動時,其電(dian)源為一級負荷,且備用電(dian)源的容(rong)量,能使屏(ping)蔽門控(kong)制系統在1h內(nei)對(dui)每側滑動門開/關操(cao)作5次(ci)。

    《城市軌道交通站臺屏蔽(bi)門》標準規(gui)定:備(bei)用(yong)?電(dian)源(yuan)(yuan)宜作為獨立(li)的一個系統進行配置,應(ying)(ying)采用(yong)一級負(fu)荷供電(dian)。驅動電(dian)源(yuan)(yuan)和控制電(dian)源(yuan)(yuan)應(ying)(ying)分別獨立(li)設置,驅動備(bei)用(yong)電(dian)源(yuan)(yuan)的儲能(neng)應(ying)(ying)能(neng)滿足(zu)30min內至(zhi)少(shao)完成開/管滑動門的一次循環,控制備(bei)用(yong)電(dian)源(yuan)(yuan)儲能(neng)至(zhi)少(shao)應(ying)(ying)滿足(zu)負(fu)載(zai)持續工作30min。

    截至目前為止,國內(nei)各地鐵(tie)工程屏蔽(bi)門(men)系(xi)統后備(bei)電源容(rong)量的(de)實際(ji)執行情況是,有(you)的(de)項目考(kao)慮1 h內(nei)對每側滑動門(men)開/關操作至少5次,有(you)的(de)項目采用30min內(nei)對每側滑動門(men)開/關操作至少3次。

由于UPS及其備用蓄電(dian)池在應(ying)急狀(zhuang)態(tai)下使用頻率極低,目(mu)(mu)前(qian)市場上(shang)有(you)人提出(chu)取(qu)消后備電(dian)源以減少投資,持這一觀點者(zhe)認為:①屏(ping)(ping)(ping)蔽門(men)系(xi)統的(de)(de)用電(dian)等(deng)(deng)級為1級負荷,即它與車(che)輛(liang)、信號(hao)等(deng)(deng)同屬最(zui)高級別(bie)的(de)(de)供(gong)電(dian),理論上(shang)來說,屏(ping)(ping)(ping)蔽門(men)的(de)(de)供(gong)電(dian)故(gu)障也意味車(che)輛(liang)等(deng)(deng)的(de)(de)供(gong)電(dian)故(gu)障,出(chu)現此種(zhong)情況時列車(che)應(ying)已停運(yun),因(yin)此屏(ping)(ping)(ping)蔽門(men)的(de)(de)繼(ji)續供(gong)電(dian)已無必要性(xing)。②從國(guo)外(wai)的(de)(de)以往工程項目(mu)(mu)經驗來看,有(you)的(de)(de)項目(mu)(mu)未(wei)采用UPS和蓄電(dian)池供(gong)電(dian),對運(yun)營未(wei)產生任何影響,因(yin)此亦提出(chu)取(qu)消UPS及后備蓄電(dian)池方案。

3. 屏(ping)蔽門系統后備電源(yuan)的既(ji)有設計方案(an)與(yu)取消(xiao)后備電源(yuan)設計方案(an)的比(bi)較

3.1 既有設計方案

    在既有設(she)計中,屏蔽門系統(tong)電源(yuan)系統(tong)包(bao)括控制電源(yuan)和驅動電源(yuan)兩種。兩種電源(yuan)設(she)計方案如下:

1) 控制電(dian)源

    由于控(kong)制(zhi)電(dian)(dian)源(yuan)(yuan)為屏蔽門系統的控(kong)制(zhi)主機、監視主機、接口繼(ji)電(dian)(dian)器等提(ti)供電(dian)(dian)源(yuan)(yuan),故(gu)其電(dian)(dian)源(yuan)(yuan)的重要(yao)(yao)(yao)性和穩定性要(yao)(yao)(yao)求較高。雖(sui)然各(ge)廠家依據其產品內部特點略有不(bu)同,但控(kong)制(zhi)電(dian)(dian)源(yuan)(yuan)的供配電(dian)(dian)原(yuan)理和涉及(ji)部件/內容基本相似。其中一種方案主要(yao)(yao)(yao)如下(xia):

    UPS輸出(chu)220V,50HZ的純凈正弦交流(liu)電(dian),經24V整流(liu)模塊整流(liu)后輸出(chu)DC24V控制電(dian)源為(wei)PSC柜內的繼電(dian)器(qi)、監控主機等元器(qi)件供電(dian)。

    UPS輸(shu)出(chu)一路(lu)(lu)AC220V直接(jie)給PSC柜,在(zai)(zai)PSC柜內經(jing)過(guo)變(bian)壓、整流(liu)和濾波后輸(shu)出(chu)DC60V供與信(xin)(xin)號(hao)(hao)專業接(jie)口的電(dian)氣(qi)回路(lu)(lu)(即與信(xin)(xin)號(hao)(hao)系統接(jie)口繼電(dian)器)使用。在(zai)(zai)信(xin)(xin)號(hao)(hao)回路(lu)(lu)中,可通過(guo)調(diao)節滑動變(bian)阻器的阻值,使得(de)當觸點閉合時,繼電(dian)器線圈上的電(dian)壓在(zai)(zai)允許范圍(wei)內。參見(jian)圖(tu)2所示。

 

  ;                              圖2  屏蔽門系(xi)統(tong)與信號系(xi)統(tong)接(jie)口電路(lu)示(shi)意

    由于UPS的(de)特點是無論(lun)市電(dian)(dian)(dian)輸(shu)入是否(fou)存在波動,輸(shu)出總為穩定的(de)AC220V電(dian)(dian)(dian)源(yuan),從(cong)而(er)可(ke)保證與信號接(jie)口回路的(de)DC60V/DC24V電(dian)(dian)(dian)源(yuan)的(de)穩定性,因此在屏(ping)蔽門系統控制電(dian)(dian)(dian)源(yuan)供電(dian)(dian)(dian)回路中一般都采用了UPS。

    同時(shi)由于(yu)設(she)置一定容量(liang)的(de)蓄電池(chi),可保證在(zai)市(shi)電停電后的(de)一段時(shi)間(jian)內監視主機(ji)仍可持續工作(zuo)一段時(shi)間(jian),從而完(wan)成內部數據的(de)處(chu)理(li)和存儲工作(zuo),滿足運營的(de)需要。

2) 驅動電源

    屏(ping)蔽(bi)門(men)系(xi)統(tong)(tong)驅動(dong)(dong)電(dian)(dian)(dian)(dian)機(ji)均為直(zhi)流(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)機(ji),主要(yao)有DC48V、DC110V兩種,其驅動(dong)(dong)電(dian)(dian)(dian)(dian)源(yuan)部分(fen)的(de)供(gong)電(dian)(dian)(dian)(dian)方(fang)式(shi)主要(yao)有兩種:直(zhi)流(liu)(liu)(liu)(liu)供(gong)電(dian)(dian)(dian)(dian)方(fang)式(shi)(即在設備室(shi)進行(xing)集中整流(liu)(liu)(liu)(liu)然后再(zai)分(fen)配到各(ge)門(men)機(ji)的(de)用電(dian)(dian)(dian)(dian))或交流(liu)(liu)(liu)(liu)供(gong)電(dian)(dian)(dian)(dian)方(fang)式(shi)(即在每個門(men)單元處進行(xing)分(fen)散整流(liu)(liu)(liu)(liu))。具(ju)體采(cai)用哪種方(fang)案除個別項目(mu)明(ming)確(que)要(yao)求以外,絕大部分(fen)項目(mu)主要(yao)取決于各(ge)屏(ping)蔽(bi)門(men)系(xi)統(tong)(tong)供(gong)貨商(shang)的(de)技(ji)術(shu)優勢(shi)而不同。在國(guo)內外主要(yao)的(de)四家(jia)屏(ping)蔽(bi)門(men)系(xi)統(tong)(tong)供(gong)應商(shang)中,英國(guo)Westinghouse習慣于采(cai)用交流(liu)(liu)(liu)(liu)供(gong)電(dian)(dian)(dian)(dian)方(fang)式(shi),而法國(guo)Faiveley公司、瑞士KABA公司和日本Nabco公司則多采(cai)用直(zhi)流(liu)(liu)(liu)(liu)供(gong)電(dian)(dian)(dian)(dian)方(fang)式(shi)。

   ①屏蔽門(men)系統電源包括門(men)機驅動電源和控制電源,分(fen)開配電。

   ②針(zhen)對(dui)本工(gong)(gong)程每輛(liang)車(che)(che)(che)5樘(tang)車(che)(che)(che)門的(de)特點,驅動電源(yuan)的(de)輸出回路(lu)數至少為5路(lu),即對(dui)應(ying)(ying)每節車(che)(che)(che)廂(xiang)五道車(che)(che)(che)門的(de)5樘(tang)滑動門分別采(cai)用不(bu)同的(de)輸出回路(lu),以保(bao)證對(dui)應(ying)(ying)一(yi)節車(che)(che)(che)廂(xiang)的(de)其中(zhong)一(yi)個(ge)回路(lu)電源(yuan)故障時,對(dui)應(ying)(ying)該車(che)(che)(che)廂(xiang)其余4個(ge)車(che)(che)(che)門的(de)滑動門能夠正常工(gong)(gong)作;

   ③屏(ping)蔽門(men)系(xi)(xi)統(tong)應(ying)配有UPS和蓄(xu)(xu)電(dian)池組(zu)作(zuo)為(wei)備用電(dian)源(yuan)。當事故停電(dian)時(shi),由UPS和蓄(xu)(xu)電(dian)池組(zu)對屏(ping)蔽門(men)系(xi)(xi)統(tong)供電(dian)。其容(rong)量應(ying)保證在事故停電(dian)時(shi),能使屏(ping)蔽門(men)控制系(xi)(xi)統(tong)在1h內(nei)對每(mei)側滑動門(men)開關操作(zuo)至少5次。

    在屏蔽門(men)系統的供電(dian)(dian)中,UPS/蓄電(dian)(dian)池還同時作為(wei)整(zheng)流器(qi)功能(neng)接(jie)入屏蔽門(men)系統配電(dian)(dian)回路(lu)中,從而避免外電(dian)(dian)源波(bo)動對(dui)屏蔽門(men)系統的影響。

    采用此種(zhong)方案,設備柜一般由(you)4~5面組成(cheng),包(bao)括PSC柜+電(dian)(dian)源(yuan)柜。如(ru)(ru)果配電(dian)(dian)柜(PDP)單獨設置,則(ze)電(dian)(dian)源(yuan)部分(fen)(fen)一般包(bao)括一個(ge)PDP+控(kong)制(zhi)電(dian)(dian)源(yuan)+驅(qu)動(dong)電(dian)(dian)源(yuan)+蓄電(dian)(dian)池(chi)(chi)。如(ru)(ru)果PDP不單獨設置,則(ze)電(dian)(dian)源(yuan)部分(fen)(fen)的設備柜將由(you)控(kong)制(zhi)電(dian)(dian)源(yuan)+驅(qu)動(dong)電(dian)(dian)源(yuan)+蓄電(dian)(dian)池(chi)(chi)組成(cheng)。其設備室(shi)大小(xiao)(xiao)要求宜為(wei)6m×4m,困難情況(kuang)下不小(xiao)(xiao)于5.2m×3.2m(凈)。

3.2 取消UPS和蓄電池的變(bian)更方案(an)

    仍(reng)分控(kong)制電源(yuan)和(he)驅(qu)動(dong)電源(yuan)進(jin)行分析。

3) 控制電源

    控制電(dian)(dian)(dian)源如取消UPS和蓄電(dian)(dian)(dian)池(chi)后,則直接進行整流和電(dian)(dian)(dian)源分(fen)配滿足(zu)PSC、信號接口等的用電(dian)(dian)(dian)需求。

4) 驅(qu)動(dong)電源

    驅動電源(yuan)如取消蓄電池,則直接由外(wai)電源(yuan)進(jin)行整(zheng)流、分(fen)配(pei)后提供(gong)屏蔽門單元(yuan)用電。

采用此種方(fang)案,設(she)(she)(she)備(bei)柜(ju)一般(ban)由3~4個(最(zui)緊湊(cou)情況(kuang)下(xia)2面,但電(dian)(dian)源(yuan)(yuan)柜(ju)可能比較(jiao)擁擠)組(zu)成(cheng), 包括PSC柜(ju)+電(dian)(dian)源(yuan)(yuan)柜(ju)。如(ru)果(guo)配電(dian)(dian)柜(ju)(PDP)單獨設(she)(she)(she)置,則電(dian)(dian)源(yuan)(yuan)部分一般(ban)包括一個PDP+控(kong)制電(dian)(dian)源(yuan)(yuan)+驅動(dong)電(dian)(dian)源(yuan)(yuan)+蓄(xu)電(dian)(dian)池。如(ru)果(guo)PDP不單獨設(she)(she)(she)置,則電(dian)(dian)源(yuan)(yuan)部分的設(she)(she)(she)備(bei)柜(ju)將由控(kong)制電(dian)(dian)源(yuan)(yuan)+驅動(dong)電(dian)(dian)源(yuan)(yuan)+蓄(xu)電(dian)(dian)池組(zu)成(cheng)。其設(she)(she)(she)備(bei)室大小要求宜為4m×4m,困難(nan)情況(kuang)下(xia)不小于3.5m×3.2m(凈)。

設置(zhi)與(yu)取消UPS和蓄電(dian)池后(hou)的(de)電(dian)源(yuan)系統配電(dian)方案的(de)比較參(can)見(jian)圖3所(suo)示。

 

                                                  設(she)置UPS和(he)蓄電池(chi)                     取(qu)消UPS和(he)蓄電池(chi)

                                                         圖3  設置和(he)取消UPS、蓄電池(chi)對照圖

    設置UPS和蓄電(dian)池的(de)(de)方(fang)案是目前國內屏(ping)(ping)蔽(bi)門(men)系(xi)(xi)統項(xiang)目普遍采用的(de)(de)。但是從圖中也(ye)可看出(chu),如果“交流輸入”的(de)(de)供電(dian)質量(包括電(dian)源波(bo)動、供電(dian)可靠(kao)率等)能完(wan)全(quan)滿足屏(ping)(ping)蔽(bi)門(men)系(xi)(xi)統的(de)(de)需求,同時在雙(shuang)路外電(dian)源均停電(dian)后(hou)如果車站現場運營管理能跟上,則取消UPS和蓄電(dian)池從理論上來說也(ye)是可以的(de)(de)。

4. 取(qu)消UPS和(he)蓄電池(chi)可(ke)能存在的問(wen)題分(fen)析探討(tao)

4.1 如(ru)果控制電(dian)源取消UPS和蓄電(dian)池

    如果控制電(dian)源取消(xiao)UPS,即AC220V電(dian)源不從UPS取,而直接(jie)取自市電(dian)一級負荷(he),那么如果市電(dian)出現波動(超過(guo)一定允許范圍),將直接(jie)影(ying)響信(xin)號(PSD-SIG)回路(lu)電(dian)壓的(de)穩(wen)定性(xing)(xing),有可能(neng)使得相(xiang)關繼電(dian)器不能(neng)工作在允許的(de)電(dian)壓范圍內,影(ying)響信(xin)號的(de)穩(wen)定性(xing)(xing)。

    如果控制電源取消(xiao)UPS和蓄電池,則一旦(dan)市(shi)電停電,則監視主機(ji)立即停止(zhi)工作(zuo),可能會丟(diu)失一定的數據,不利于后期運(yun)營管理(li)。

    另外屏蔽門的控制系統(tong)一般為(wei)一臺工控機,如果突然斷電有(you)可(ke)能(neng)會(hui)造成(cheng)其軟件的損壞導致系統(tong)癱瘓。

4.2 如果(guo)取消(xiao)UPS和蓄電(dian)池增加告警功能

    雖然可以(yi)在(zai)(zai)設計中要求實現一路(lu)或(huo)(huo)兩(liang)路(lu)外電(dian)源失(shi)電(dian)時(shi)(shi)配(pei)電(dian)盤(pan)具備告警(jing)功(gong)(gong)能,但(dan)是(shi)兩(liang)路(lu)交(jiao)流電(dian)源失(shi)電(dian)的(de)情(qing)況(kuang)下(xia),即(ji)使(shi)有告警(jing)功(gong)(gong)能也對屏(ping)蔽(bi)(bi)門有比(bi)較(jiao)大的(de)影(ying)響。因為(wei)一個車(che)站(zhan)兩(liang)路(lu)交(jiao)流電(dian)源都失(shi)電(dian)時(shi)(shi),嚴(yan)重的(de)狀(zhuang)況(kuang)為(wei)本站(zhan)降壓變電(dian)所退出運行(xing),整個車(che)站(zhan)(特別是(shi)地(di)下(xia)站(zhan))處于應(ying)急照明(ming)狀(zhuang)態,公(gong)共區照度(du)只有正常(chang)照明(ming)的(de)1/10,此時(shi)(shi)應(ying)疏(shu)散站(zhan)內旅客;如果列車(che)在(zai)(zai)區間阻塞(如牽引供電(dian)中斷或(huo)(huo)火災狀(zhuang)況(kuang)),勢必要進(jin)行(xing)乘客疏(shu)散,乘客需通(tong)過屏(ping)蔽(bi)(bi)門進(jin)入站(zhan)臺(tai)(tai),從(cong)而由車(che)站(zhan)疏(shu)散到(dao)地(di)面,這種情(qing)況(kuang)下(xia)需要及時(shi)(shi)打開(kai)屏(ping)蔽(bi)(bi)門,否則勢必造(zao)成人員恐慌反而不能及時(shi)(shi)疏(shu)散乘客,惡劣(lie)情(qing)況(kuang)下(xia)有可能造(zao)成嚴(yan)重后(hou)果。雖然屏(ping)蔽(bi)(bi)門具備手動解鎖(suo)功(gong)(gong)能,但(dan)該功(gong)(gong)能應(ying)是(shi)在(zai)(zai)其它開(kai)門功(gong)(gong)能都失(shi)效(xiao)的(de)不得已的(de)情(qing)況(kuang)下(xia)才考(kao)慮(lv)使(shi)用。而且乘客在(zai)(zai)慌亂之下(xia)不一定(ding)能及時(shi)(shi)解鎖(suo)開(kai)門疏(shu)散,同時(shi)(shi)站(zhan)臺(tai)(tai)值班人員也不一定(ding)能確保在(zai)(zai)任(ren)何情(qing)況(kuang)下(xia)均可在(zai)(zai)站(zhan)臺(tai)(tai)側解鎖(suo)打開(kai)屏(ping)蔽(bi)(bi)門,因此可能影(ying)響安(an)全疏(shu)散。

(1) 如果取消后備電源屏蔽門失電時全開啟

    如果取消(xiao)屏蔽(bi)門(men)后備電源(yuan),考慮在雙路外電源(yuan)都失效的情況下(xia)屏蔽(bi)門(men)自動全部開啟,我們認為存(cun)在安全隱患。因為在工程設置(zhi)屏蔽(bi)門(men)后,乘客已經(jing)適應(ying)了有(you)(you)屏蔽(bi)門(men)的乘車方式,在此情況下(xia)屏蔽(bi)門(men)關閉應(ying)屬于(yu)安全狀態,否則開啟將是不(bu)安全的。這種(zhong)狀況的全開門(men)功能與工程本(ben)身并(bing)未設置(zhi)屏蔽(bi)門(men)時的安全標準應(ying)有(you)(you)所(suo)不(bu)同。

    因此(ci)(ci),從(cong)上述(shu)分(fen)析,鑒于(yu)目前(qian)國內一級(ji)負(fu)荷供(gong)電(dian)不能完全滿(man)足屏蔽(bi)(bi)門(men)系統的(de)需要(yao)(影響(xiang)供(gong)電(dian)可靠性的(de)因素比較多,如元器件、各處供(gong)配電(dian)開關(guan)等(deng)均可能存在(zai)故障,而且國內地鐵(tie)系統或多或少地發生過雙路外電(dian)源停電(dian)而用后備電(dian)源的(de)情況),因此(ci)(ci)在(zai)屏蔽(bi)(bi)門(men)電(dian)源系統中取消(xiao)UPS和蓄(xu)電(dian)池存在(zai)一定的(de)風(feng)險,還是有必要(yao)存在(zai)的(de)。

    對于后備電(dian)(dian)源(yuan)的(de)容量可(ke)以根據(ju)運(yun)營需求(qiu)等因素適當調整。如果必須考慮降低后備電(dian)(dian)源(yuan)容量,可(ke)以根據(ju)運(yun)營的(de)要(yao)求(qiu)采取小(xiao)容量的(de)蓄電(dian)(dian)池。如從(cong)停(ting)電(dian)(dian)后控(kong)制(zhi)電(dian)(dian)源(yuan)可(ke)在1h內(nei)每側滑動門(men)開(kai)(kai)關操(cao)作5次減少(shao)為30min內(nei)可(ke)對每側滑動門(men)開(kai)(kai)關操(cao)作1次,保證停(ting)電(dian)(dian)后至(zhi)少(shao)可(ke)保證整列門(men)開(kai)(kai)啟和關閉一次滿足(zu)疏散后再關閉,除非人為手動開(kai)(kai)啟。

5. 結論

    綜上(shang)所(suo)述,我們認為屏(ping)蔽門系統UPS和蓄(xu)電(dian)池能否(fou)取消(xiao)主要取決于(yu)市電(dian)(一級負荷(he))的供(gong)電(dian)質(zhi)量和可(ke)靠性以(yi)及停電(dian)故(gu)障時運營的應急(ji)處(chu)理措施和對故(gu)障的接(jie)受程(cheng)度。也就是說在滿足以(yi)下(xia)條(tiao)件(jian)的情況下(xia)才(cai)可(ke)考慮取消(xiao)UPS和后備電(dian)源:

(1) 電源波動情況(kuang)能(neng)夠滿足屏蔽門(men)控制(zhi)系統的要(yao)求;

(2) 可靠性(xing)比較高,能避免(mian)兩路電源均(jun)停電;

(3) 外(wai)電源停電后,運營部門(men)能(neng)夠(gou)加強車(che)站(zhan)現場的應(ying)急開門(men)功能(neng),即可提(ti)前將門(men)打(da)開,迎(ying)接區間疏散乘(cheng)客。

    但是根(gen)據國內地鐵工(gong)程(cheng)的實(shi)際應用情況,以(yi)及地鐵外市政供電反(fan)饋情況,由于市電供電環節較多,外電源(yuan)停(ting)電和(he)電源(yuan)波(bo)動有可(ke)能(neng)超過屏(ping)蔽門系統(tong)的要求(qiu)都存在(zai)可(ke)能(neng),故為(wei)確保(bao)(bao)屏(ping)蔽門系統(tong)安全可(ke)靠運行,應仍然保(bao)(bao)留UPS和(he)蓄(xu)電池。

   ; 如果(guo)從降低投資和設備室發熱(re)量等(deng)因素考慮,可(ke)(ke)以考慮采用UPS配備小(xiao)容量蓄電池作為屏(ping)蔽(bi)門電源(yuan)系統的(de)(de)(de)后備電源(yuan),在兩(liang)路(lu)交流電源(yuan)失電的(de)(de)(de)情(qing)況(kuang)下,系統能(neng)夠(gou)實現屏(ping)蔽(bi)門可(ke)(ke)以開啟和關閉至(zhi)少一次滿足疏散(san)后再關閉的(de)(de)(de)功能(neng),以保證安全(quan)。

參考文獻:

篇9

關鍵(jian)詞 智(zhi)能汽車競賽;電(dian)源管理(li)模塊;電(dian)機驅(qu)動模塊

中圖(tu)分(fen)類號 TP2 文獻標識碼(ma) A 文章(zhang)編號 2095-6363(2015)09-0032-02

全國大(da)學(xue)生“飛思卡爾”杯智能汽車(che)競賽(sai)是(shi)以“立(li)足(zu)培養(yang)、重在參與、鼓勵(li)探索、追求(qiu)卓越”為(wei)宗旨,鼓勵(li)創(chuang)新的一項科技競賽(sai)。以飛思卡爾半導(dao)體公(gong)司的微處理器為(wei)核心,通過自主設(she)計傳感器、電源管(guan)理模(mo)塊(kuai)、電機(ji)驅動模(mo)塊(kuai)和(he)編寫控(kong)制程序,制作一個能按(an)照比賽(sai)規則自動識別賽(sai)道完成(cheng)比賽(sai)的模(mo)型汽車(che)。

硬(ying)件是智能車的(de)基礎,其影(ying)響著車模系統穩定(ding)性。基于此,本文主要提出一套電(dian)源管(guan)理模塊、電(dian)機驅動(dong)模塊的(de)可(ke)行(xing)設計(ji)方案。

1 電源管理模塊

根據調(diao)整(zheng)管的(de)工作(zuo)狀態(tai)(tai),直流穩(wen)壓(ya)電(dian)(dian)(dian)源分為(wei)線性(xing)(xing)穩(wen)壓(ya)電(dian)(dian)(dian)源和(he)開(kai)(kai)關(guan)穩(wen)壓(ya)電(dian)(dian)(dian)源。線性(xing)(xing)穩(wen)壓(ya)電(dian)(dian)(dian)源通過采(cai)樣、反(fan)饋等方式來控制調(diao)整(zheng)管的(de)導(dao)通程度,其輸出電(dian)(dian)(dian)壓(ya)文波(bo)比(bi)較小(xiao)、工作(zuo)噪聲小(xiao)、反(fan)應速度快(kuai);調(diao)整(zheng)管工作(zuo)在放(fang)大狀態(tai)(tai),效率比(bi)較低,發熱量大。在開(kai)(kai)關(guan)穩(wen)壓(ya)電(dian)(dian)(dian)源中,開(kai)(kai)關(guan)管工作(zuo)飽和(he)或者截止狀態(tai)(tai),對應開(kai)(kai)、關(guan)兩個狀態(tai)(tai);效率高,功耗小(xiao),存在比(bi)較嚴重的(de)開(kai)(kai)關(guan)干擾。

電(dian)(dian)源管(guan)理模(mo)(mo)塊(kuai)為車模(mo)(mo)系統(tong)的(de)(de)各(ge)(ge)(ge)個模(mo)(mo)塊(kuai)供電(dian)(dian),其供電(dian)(dian)穩定性(xing)是車模(mo)(mo)穩定運行的(de)(de)基礎。在設(she)計中(zhong),不僅要考慮各(ge)(ge)(ge)個模(mo)(mo)塊(kuai)的(de)(de)正(zheng)常工作(zuo)電(dian)(dian)壓(ya)(ya)(ya)、電(dian)(dian)流,還要做好各(ge)(ge)(ge)個模(mo)(mo)塊(kuai)的(de)(de)隔離,減小(xiao)模(mo)(mo)塊(kuai)之間的(de)(de)噪(zao)聲干擾。總的(de)(de)來說,通(tong)過三端集成穩壓(ya)(ya)(ya)芯片來給(gei)各(ge)(ge)(ge)個模(mo)(mo)塊(kuai)來供電(dian)(dian)。競(jing)賽中(zhong),常用的(de)(de)電(dian)(dian)源有串(chuan)聯型線性(xing)穩壓(ya)(ya)(ya)電(dian)(dian)源(LM2941、TPS系列(lie)等)和開(kai)關型穩壓(ya)(ya)(ya)電(dian)(dian)源(LM2596、LM2575、AS1015等)兩大類。

車模(mo)電(dian)(dian)(dian)(dian)(dian)(dian)源是7.2V2000mAh的(de)(de)鎳鎘(ge)可充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)池,其對車模(mo)的(de)(de)各個(ge)模(mo)塊(kuai)供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)。系統的(de)(de)供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)示(shi)意圖(tu)如圖(tu)1所示(shi),7.2V電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)給(gei)不(bu)同電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)的(de)(de)模(mo)塊(kuai)供(gong)電(dian)(dian)(dian)(dian)(dian)(dian),主要的(de)(de)模(mo)塊(kuai)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)有12V、5.5V、5V和3.3V。用電(dian)(dian)(dian)(dian)(dian)(dian)池給(gei)電(dian)(dian)(dian)(dian)(dian)(dian)機供(gong)電(dian)(dian)(dian)(dian)(dian)(dian),將電(dian)(dian)(dian)(dian)(dian)(dian)源電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)經升(sheng)、降壓(ya)再給(gei)其他模(mo)塊(kuai)供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)。電(dian)(dian)(dian)(dian)(dian)(dian)機驅動芯片(pian)(pian)IR2104的(de)(de)供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)為(wei)12V,S-D5舵機的(de)(de)供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)為(wei)5.5V,線性CCD的(de)(de)供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)為(wei)5V,單片(pian)(pian)機的(de)(de)供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)為(wei)5V,調參模(mo)塊(kuai)等供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)為(wei)5V和3.3V。

MC9S12XS128單(dan)片(pian)(pian)機是(shi)系統的控制中心(xin),其(qi)工(gong)作的穩(wen)(wen)定性(xing)(xing)直(zhi)接影響車模運行。為了(le)減(jian)少其(qi)他模塊對(dui)其(qi)干擾,采用低壓(ya)(ya)(ya)(ya)差線(xian)性(xing)(xing)穩(wen)(wen)壓(ya)(ya)(ya)(ya)電源(yuan)供電。TPS7350具有過流(liu)、過壓(ya)(ya)(ya)(ya)和(he)電壓(ya)(ya)(ya)(ya)反(fan)接保護(hu)電路,可以有效地保護(hu)單(dan)片(pian)(pian)機;最(zui)大輸出電流(liu)500mA,大于單(dan)片(pian)(pian)機工(gong)作電流(liu);穩(wen)(wen)壓(ya)(ya)(ya)(ya)線(xian)度相對(dui)比較好。所以選用TPS7350對(dui)其(qi)單(dan)獨(du)供電。線(xian)性(xing)(xing)CCD工(gong)作條(tiao)件(jian)(jian)電源(yuan)電壓(ya)(ya)(ya)(ya)為-0.3V-6V,考(kao)慮到單(dan)片(pian)(pian)機的AD采樣轉化精度和(he)線(xian)性(xing)(xing)CCD推薦工(gong)作條(tiao)件(jian)(jian)等原(yuan)因,選其(qi)最(zui)佳工(gong)作電壓(ya)(ya)(ya)(ya)5V。VDD最(zui)大連續電流(liu)為40mA,在比賽中一般需(xu)要用到2-4個線(xian)性(xing)(xing)CCD,最(zui)大電流(liu)一般不超過200mA。線(xian)性(xing)(xing)CCD是(shi)模擬傳感(gan)器,其(qi)供電電源(yuan)的波動(dong)將影響其(qi)性(xing)(xing)能, TPS7350穩(wen)(wen)壓(ya)(ya)(ya)(ya)后電壓(ya)(ya)(ya)(ya)波動(dong)較小,用其(qi)對(dui)線(xian)性(xing)(xing)CCD單(dan)獨(du)供電。

S-D5是數字舵(duo)機(ji)(ji),工(gong)作(zuo)電壓4.5V-5.5V,正(zheng)常(chang)工(gong)作(zuo)電流200mA,堵(du)轉(zhuan)電流是800mA;工(gong)作(zuo)電壓在5.5V下,帶(dai)有堵(du)轉(zhuan)保(bao)(bao)護功能。舵(duo)機(ji)(ji)在實時(shi)(shi)控(kong)制(zhi)時(shi)(shi)存(cun)在滯后性,滯后時(shi)(shi)間的大小(xiao)主要由舵(duo)機(ji)(ji)的響(xiang)應時(shi)(shi)間和轉(zhuan)向(xiang)傳(chuan)動比決(jue)定。在轉(zhuan)向(xiang)傳(chuan)動比不變(bian)時(shi)(shi),舵(duo)機(ji)(ji)的響(xiang)應時(shi)(shi)間與供(gong)電電壓有關;舵(duo)機(ji)(ji)的工(gong)作(zuo)電壓越(yue)高,響(xiang)應越(yue)快,同(tong)時(shi)(shi)扭矩力(li)越(yue)大。選(xuan)擇5.5V供(gong)電,既可(ke)提高舵(duo)機(ji)(ji)響(xiang)應速度,又(you)可(ke)以保(bao)(bao)護舵(duo)機(ji)(ji)。LM2941S是低壓差線性穩(wen)壓芯片,原理圖如其輸出電壓,在輸出電流時(shi)(shi),。選(xuan)用為,為,計算得。

常用的(de)調參模塊(kuai)主要有藍牙、SD卡(ka)、OLED顯示(shi)屏(ping)(ping)和按鍵等。不(bu)同(tong)調參模塊(kuai)的(de)電(dian)(dian)壓不(bu)同(tong),SD卡(ka)供電(dian)(dian)電(dian)(dian)壓為3.3V,藍牙、OLED顯示(shi)屏(ping)(ping)可以接3.3V或者5V,按鍵一(yi)般接5V。測速模塊(kuai)一(yi)般供電(dian)(dian)5V。這些模塊(kuai)電(dian)(dian)流一(yi)般較小,可以根據PCB設計的(de)需要調整各模塊(kuai)的(de)電(dian)(dian)壓分配。

2 電機驅動模塊

在競(jing)賽中,電機驅(qu)動的(de)方(fang)式一般有(you)兩種方(fang)式:集成芯片(pian)(pian)、柵極驅(qu)動芯片(pian)(pian)和N溝(gou)道MOSFET。常用的(de)集成驅(qu)動芯片(pian)(pian)有(you)BTN7970、BTN7971等;常用的(de)柵極驅(qu)動芯片(pian)(pian)有(you)IR系(xi)列的(de)IR2104、IR2184等;常用N溝(gou)道MOSFET型號多樣。

集(ji)成(cheng)(cheng)驅(qu)動(dong)(dong)(dong)(dong)芯(xin)片(pian)在過(guo)流(liu)、短路、過(guo)溫和欠(qian)壓時,芯(xin)片(pian)自動(dong)(dong)(dong)(dong)關斷輸(shu)入。為了防止車(che)模在運行過(guo)程(cheng)中因為芯(xin)片(pian)保(bao)護(hu)而(er)停止工(gong)作(zuo),在設(she)計時要考慮(lv)過(guo)流(liu)保(bao)護(hu)、散熱(re)等(deng)情況并采取措施。而(er)B型車(che)模電(dian)機(ji)功(gong)率比較(jiao)大(da),正常工(gong)作(zuo)電(dian)流(liu)都(dou)要大(da)于1A,在啟(qi)動(dong)(dong)(dong)(dong)或者堵轉的情況下,電(dian)流(liu)會更大(da),很容易造成(cheng)(cheng)驅(qu)動(dong)(dong)(dong)(dong)芯(xin)片(pian)發熱(re);如若散熱(re)不好,會影(ying)響(xiang)(xiang)芯(xin)片(pian)正常工(gong)作(zuo),進(jin)而(er)影(ying)響(xiang)(xiang)車(che)模運行。所(suo)以(yi)采用半橋(qiao)驅(qu)動(dong)(dong)(dong)(dong)芯(xin)片(pian)IR2104驅(qu)動(dong)(dong)(dong)(dong)4個LR7843型N溝道MOSFET H橋(qiao)的方(fang)式來驅(qu)動(dong)(dong)(dong)(dong)電(dian)機(ji)。

首(shou)先了(le)解(jie)一(yi)下(xia)H橋(qiao)(qiao)驅動原理,電機和(he)4個(ge)N溝道MOSFET共同(tong)構成(cheng)一(yi)個(ge)類似(si)于字(zi)母H的驅動橋(qiao)(qiao),如圖4所示(shi)。當(dang)Q1、Q4導通(tong)(tong)時(shi)(shi),直(zhi)流電機中(zhong)通(tong)(tong)過(guo)從左到右(you)的電流;當(dang)Q2、Q3導通(tong)(tong)時(shi)(shi),直(zhi)流電機中(zhong)通(tong)(tong)過(guo)從右(you)到左的電流;流經電機電流方向的改變(bian)就可(ke)以(yi)實現電機的正(zheng)反轉(zhuan)(zhuan)。但是,在控(kong)制(zhi)4個(ge)N溝道MOSFET導通(tong)(tong)時(shi)(shi),同(tong)一(yi)橋(qiao)(qiao)臂的Q1和(he)Q2、Q3和(he)Q4不能(neng)同(tong)時(shi)(shi)導通(tong)(tong),導通(tong)(tong)會(hui)造成(cheng)源地的短路;在兩次狀態(tai)轉(zhuan)(zhuan)換(huan)過(guo)程中(zhong)可(ke)能(neng)出現瞬時(shi)(shi)短路,需(xu)要(yao)在轉(zhuan)(zhuan)換(huan)時(shi)(shi)插入“死(si)區(qu)”。在這里,采用一(yi)片柵極驅動芯(xin)片IR2104來(lai)驅動同(tong)一(yi)橋(qiao)(qiao)臂上(shang)下(xia)兩個(ge)NMOS管(guan)導通(tong)(tong)。IR2104內部(bu)集成(cheng)升壓電路,一(yi)個(ge)自(zi)舉二極管(guan)和(he)―個(ge)自(zi)舉電容便可(ke)完成(cheng)自(zi)舉升壓。IR2104內部(bu)設置死(si)區(qu)時(shi)(shi)間(jian),存在于在每次狀態(tai)轉(zhuan)(zhuan)換(huan)時(shi)(shi),可(ke)以(yi)保證同(tong)一(yi)橋(qiao)(qiao)臂上(shang)、下(xia)兩管(guan)的狀態(tai)相反。

NMOS管(guan)是(shi)電(dian)(dian)(dian)壓驅動(dong)(dong)型(xing)器件,柵極(ji)(ji)電(dian)(dian)(dian)壓高(gao)于源極(ji)(ji)電(dian)(dian)(dian)壓即(ji)可實現NMOS的(de)(de)飽和(he)導通(tong)。電(dian)(dian)(dian)壓通(tong)斷MOS管(guan)時,要比大(da)10V以上,而(er)且(qie)開(kai)通(tong)時必須工(gong)作(zuo)(zuo)在飽和(he)導通(tong)狀(zhuang)態。IR2104工(gong)作(zuo)(zuo)電(dian)(dian)(dian)壓為10-20V,采用(yong)B0512S隔離電(dian)(dian)(dian)源升壓模塊來(lai)供電(dian)(dian)(dian),IR2104輸出達到(dao)15V左右(you),可以驅動(dong)(dong)NMOS管(guan)。NMOS管(guan)柵源極(ji)(ji)之(zhi)間是(shi)容性(xing)結構,柵極(ji)(ji)回路存在寄(ji)生(sheng)電(dian)(dian)(dian)感,合適的(de)(de)柵極(ji)(ji)電(dian)(dian)(dian)阻可以迅速衰減(jian)柵極(ji)(ji)回路在驅動(dong)(dong)芯片驅動(dong)(dong)脈沖的(de)(de)激(ji)勵下(xia)要產(chan)生(sheng)很強的(de)(de)振蕩(dang)。LR7843型(xing)N溝道MOSFET,。電(dian)(dian)(dian)機驅動(dong)(dong)模塊設計電(dian)(dian)(dian)路圖如圖4。

3 結論

本(ben)文(wen)的電路方案經過測試,證(zheng)明(ming)了(le)其可(ke)行性與(yu)可(ke)靠(kao)(kao)性。在車模(mo)系統中(zhong),各個模(mo)塊能穩定可(ke)靠(kao)(kao)地運行。

篇10

關鍵詞:不間斷(duan)交流電源;過流保護(hu);SPWM

不(bu)間(jian)(jian)斷交(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源[1]正(zheng)常是用于在(zai)有(you)交(jiao)流(liu)(liu)(liu)輸(shu)(shu)入(ru)時(shi)交(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian),當(dang)交(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)斷開或者交(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)不(bu)正(zheng)常時(shi)用電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池來供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)。在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池饋電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)交(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)供(gong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)時(shi),開機(ji)后(hou)輸(shu)(shu)出接的(de)容性負載(zai)太大(da),則負載(zai)的(de)瞬(shun)間(jian)(jian)啟(qi)動電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)就(jiu)很大(da),電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源檢(jian)測到峰值電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)關斷后(hou),輸(shu)(shu)出恢(hui)復時(shi)間(jian)(jian)太長,從而會導致輸(shu)(shu)出斷電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)故(gu)障。

1 故障分析

造成輸出斷(duan)電(dian)(dian)(dian)故障原因(yin)是(shi)在負(fu)載在開(kai)機瞬間,內部的(de)開(kai)關(guan)電(dian)(dian)(dian)源對濾波(bo)電(dian)(dian)(dian)容器充(chong)電(dian)(dian)(dian)會產生一個很大(da)的(de)浪涌電(dian)(dian)(dian)流(liu)(liu),比系統(tong)正(zheng)常(chang)工作電(dian)(dian)(dian)流(liu)(liu)大(da)幾(ji)倍(bei)乃至(zhi)幾(ji)十倍(bei)。因(yin)此電(dian)(dian)(dian)源會在負(fu)載上電(dian)(dian)(dian)瞬間出現斷(duan)電(dian)(dian)(dian)問題。采用加大(da)電(dian)(dian)(dian)源的(de)輸出功(gong)率余量和提(ti)高(gao)電(dian)(dian)(dian)源的(de)過流(liu)(liu)保(bao)護措施可以解決這個問題。

2 系統設計

系統框圖見圖1:

將(jiang)主控(kong)芯片產生SPWM脈沖[2]作為(wei)電(dian)源的控(kong)制信號(hao),經功(gong)率驅動電(dian)路驅動和保護IGBT開(kai)關(guan)(guan)管,另外(wai)電(dian)流(liu)(liu)檢測電(dian)路檢測到過流(liu)(liu)信號(hao),短時(shi)間關(guan)(guan)斷SPWM脈沖信號(hao),一旦沒有過流(liu)(liu)信號(hao),將(jiang)立刻打開(kai)SPWM脈沖信號(hao)。

產生兩路帶死區的SPWM脈(mo)沖作為電(dian)源(yuan)的控(kong)制信號,其幅(fu)值為3.3 V,經功率驅(qu)動(dong)電(dian)路放大后驅(qu)動(dong)IGBT開(kai)關(guan)管,驅(qu)動(dong)波形(xing)很平滑不(bu)會(hui)有(you)共態導通的風險。當主控(kong)芯(xin)片檢測到(dao)過流(liu)時快速關(guan)斷(duan)IGBT,起到(dao)保護(hu)IGBT的作用(yong);當無過流(liu)信號時,快速恢復(fu)控(kong)制信號,使(shi)得(de)負載不(bu)會(hui)斷(duan)電(dian)。

電(dian)(dian)(dian)(dian)(dian)源的(de)(de)(de)(de)(de)(de)(de)主開關(guan)器(qi)(qi)(qi)件(jian)(jian)IGBT遇到(dao)(dao)短路(lu)和過(guo)(guo)流(liu)(liu)(liu)時,若不(bu)加(jia)保(bao)(bao)(bao)護(hu)(hu)或(huo)者保(bao)(bao)(bao)護(hu)(hu)不(bu)當,就會(hui)(hui)失效(xiao),其主要原因(yin)有(you):超過(guo)(guo)熱極限、發(fa)(fa)(fa)生擎住效(xiao)應和超過(guo)(guo)器(qi)(qi)(qi)件(jian)(jian)耐壓(ya)(ya)(ya)(ya)三種(zhong)。為(wei)了避免這(zhe)(zhe)三種(zhong)失效(xiao)的(de)(de)(de)(de)(de)(de)(de)發(fa)(fa)(fa)生,必須(xu)對驅(qu)動(dong)電(dian)(dian)(dian)(dian)(dian)路(lu)采(cai)取適(shi)當的(de)(de)(de)(de)(de)(de)(de)措(cuo)施。通常采(cai)用的(de)(de)(de)(de)(de)(de)(de)措(cuo)施有(you)軟(ruan)關(guan)斷(duan)和降(jiang)(jiang)柵(zha)壓(ya)(ya)(ya)(ya)兩種(zhong)。軟(ruan)關(guan)斷(duan)是(shi)指(zhi)過(guo)(guo)流(liu)(liu)(liu)和短路(lu)時,關(guan)斷(duan)IGBT;降(jiang)(jiang)柵(zha)壓(ya)(ya)(ya)(ya)是(shi)指(zhi)在(zai)(zai)檢測(ce)到(dao)(dao)器(qi)(qi)(qi)件(jian)(jian)過(guo)(guo)流(liu)(liu)(liu)時,馬上降(jiang)(jiang)低柵(zha)壓(ya)(ya)(ya)(ya),但(dan)器(qi)(qi)(qi)件(jian)(jian)仍能(neng)維持導(dao)通,前(qian)者抗(kang)(kang)干(gan)擾能(neng)力(li)(li)差。一(yi)(yi)旦檢測(ce)到(dao)(dao)故(gu)障(zhang)(zhang)就關(guan)斷(duan)器(qi)(qi)(qi)件(jian)(jian),很容易發(fa)(fa)(fa)生誤動(dong)作,因(yin)而(er)為(wei)增(zeng)(zeng)加(jia)保(bao)(bao)(bao)護(hu)(hu)電(dian)(dian)(dian)(dian)(dian)路(lu)的(de)(de)(de)(de)(de)(de)(de)抗(kang)(kang)干(gan)擾能(neng)力(li)(li),往(wang)往(wang)在(zai)(zai)得(de)到(dao)(dao)故(gu)障(zhang)(zhang)信號(hao)(hao)與啟動(dong)保(bao)(bao)(bao)護(hu)(hu)電(dian)(dian)(dian)(dian)(dian)路(lu)之間加(jia)一(yi)(yi)個(ge)固(gu)定(ding)延(yan)時,然而(er)故(gu)障(zhang)(zhang)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)會(hui)(hui)在(zai)(zai)這(zhe)(zhe)固(gu)定(ding)延(yan)時內急劇(ju)上升(sheng),從而(er)大大增(zeng)(zeng)加(jia)了故(gu)障(zhang)(zhang)時器(qi)(qi)(qi)件(jian)(jian)的(de)(de)(de)(de)(de)(de)(de)功(gong)率損耗,同時故(gu)障(zhang)(zhang)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)的(de)(de)(de)(de)(de)(de)(de)增(zeng)(zeng)加(jia),還會(hui)(hui)使(shi)器(qi)(qi)(qi)件(jian)(jian)故(gu)障(zhang)(zhang)關(guan)斷(duan)時的(de)(de)(de)(de)(de)(de)(de)di/dt增(zeng)(zeng)大,它們之間的(de)(de)(de)(de)(de)(de)(de)參數(shu)設計很難折中(zhong)(zhong),因(yin)此(ci)軟(ruan)關(guan)斷(duan)保(bao)(bao)(bao)護(hu)(hu)的(de)(de)(de)(de)(de)(de)(de)驅(qu)動(dong)電(dian)(dian)(dian)(dian)(dian)路(lu),在(zai)(zai)故(gu)障(zhang)(zhang)發(fa)(fa)(fa)生時,往(wang)往(wang)是(shi)保(bao)(bao)(bao)護(hu)(hu)電(dian)(dian)(dian)(dian)(dian)路(lu)啟動(dong)了,但(dan)器(qi)(qi)(qi)件(jian)(jian)仍然損壞。后(hou)者,抗(kang)(kang)干(gan)擾能(neng)力(li)(li)強(qiang)。將柵(zha)壓(ya)(ya)(ya)(ya)后(hou)設定(ding)一(yi)(yi)個(ge)固(gu)定(ding)延(yan)時,若延(yan)時后(hou)故(gu)障(zhang)(zhang)信號(hao)(hao)依然存在(zai)(zai),則關(guan)斷(duan)器(qi)(qi)(qi)件(jian)(jian)。故(gu)障(zhang)(zhang)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)在(zai)(zai)這(zhe)(zhe)一(yi)(yi)個(ge)延(yan)時內將被限制(zhi)在(zai)(zai)一(yi)(yi)個(ge)較小(xiao)值(zhi)。故(gu)障(zhang)(zhang)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)的(de)(de)(de)(de)(de)(de)(de)限制(zhi),降(jiang)(jiang)低了故(gu)障(zhang)(zhang)時器(qi)(qi)(qi)件(jian)(jian)的(de)(de)(de)(de)(de)(de)(de)功(gong)率損耗,延(yan)長了器(qi)(qi)(qi)件(jian)(jian)抗(kang)(kang)短路(lu)的(de)(de)(de)(de)(de)(de)(de)時間,而(er)且能(neng)夠(gou)降(jiang)(jiang)低器(qi)(qi)(qi)件(jian)(jian)關(guan)斷(duan)時的(de)(de)(de)(de)(de)(de)(de)di/dt,對器(qi)(qi)(qi)件(jian)(jian)的(de)(de)(de)(de)(de)(de)(de)保(bao)(bao)(bao)護(hu)(hu)十(shi)分(fen)有(you)利,在(zai)(zai)延(yan)時中(zhong)(zhong),若故(gu)障(zhang)(zhang)信號(hao)(hao)消失,驅(qu)動(dong)電(dian)(dian)(dian)(dian)(dian)路(lu)可自動(dong)恢復正常的(de)(de)(de)(de)(de)(de)(de)工作狀態(tai),因(yin)而(er)大大增(zeng)(zeng)強(qiang)了電(dian)(dian)(dian)(dian)(dian)路(lu)的(de)(de)(de)(de)(de)(de)(de)抗(kang)(kang)干(gan)擾能(neng)力(li)(li)。從上述的(de)(de)(de)(de)(de)(de)(de)分(fen)析(xi)可以(yi)(yi)看(kan)出,降(jiang)(jiang)柵(zha)壓(ya)(ya)(ya)(ya)是(shi)一(yi)(yi)種(zhong)很好的(de)(de)(de)(de)(de)(de)(de)IGBT故(gu)障(zhang)(zhang)保(bao)(bao)(bao)護(hu)(hu)方法(fa),但(dan)在(zai)(zai)以(yi)(yi)往(wang)的(de)(de)(de)(de)(de)(de)(de)降(jiang)(jiang)柵(zha)壓(ya)(ya)(ya)(ya)電(dian)(dian)(dian)(dian)(dian)路(lu)中(zhong)(zhong),往(wang)往(wang)只考慮了柵(zha)壓(ya)(ya)(ya)(ya)與短路(lu)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)大小(xiao)的(de)(de)(de)(de)(de)(de)(de)關(guan)系,忽略(lve)了降(jiang)(jiang)柵(zha)壓(ya)(ya)(ya)(ya)的(de)(de)(de)(de)(de)(de)(de)速度。在(zai)(zai)實際過(guo)(guo)程中(zhong)(zhong)發(fa)(fa)(fa)現,降(jiang)(jiang)柵(zha)壓(ya)(ya)(ya)(ya)的(de)(de)(de)(de)(de)(de)(de)速度直接(jie)決定(ding)了故(gu)障(zhang)(zhang)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)下降(jiang)(jiang)的(de)(de)(de)(de)(de)(de)(de)速率di/dt,控制(zhi)di/dt,必須(xu)采(cai)用慢降(jiang)(jiang)柵(zha)壓(ya)(ya)(ya)(ya)技術,以(yi)(yi)通過(guo)(guo)限制(zhi)降(jiang)(jiang)柵(zha)壓(ya)(ya)(ya)(ya)的(de)(de)(de)(de)(de)(de)(de)速度來控制(zhi)故(gu)障(zhang)(zhang)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)下降(jiang)(jiang)的(de)(de)(de)(de)(de)(de)(de)速率di/dt,從而(er)抑制(zhi)器(qi)(qi)(qi)件(jian)(jian)的(de)(de)(de)(de)(de)(de)(de)dv/dt和uc的(de)(de)(de)(de)(de)(de)(de)峰值(zhi)。

實現慢降(jiang)柵壓(ya)的(de)具體電(dian)(dian)路(lu)選用(yong)新型IGBT驅(qu)動(dong)(dong)(dong)集成芯(xin)片(pian)(pian)(pian)作為(wei)驅(qu)動(dong)(dong)(dong)電(dian)(dian)路(lu),芯(xin)片(pian)(pian)(pian)采用(yong)自舉供電(dian)(dian)技(ji)術,驅(qu)動(dong)(dong)(dong)能(neng)力(li)強,動(dong)(dong)(dong)態響應快(kuai),具有電(dian)(dian)源(yuan)欠壓(ya)及(ji)功(gong)率IGBT過(guo)(guo)流(liu)軟(ruan)關(guan)斷功(gong)能(neng),只(zhi)需(xu)幾個分立(li)元件,就可直接驅(qu)動(dong)(dong)(dong)IGBT。模塊過(guo)(guo)流(liu)時,通過(guo)(guo)Vce飽和壓(ya)降(jiang)檢測電(dian)(dian)路(lu),采用(yong)兩步(bu)法(fa)軟(ruan)關(guan)斷技(ji)術,有效抑(yi)制(zhi)(zhi)dv/dt,降(jiang)低(di)EMI。在(zai)(zai)系統(tong)中,兩個驅(qu)動(dong)(dong)(dong)電(dian)(dian)路(lu)之間(jian)通過(guo)(guo)SY-FLT和FAULT/SD引腳(jiao)連接組成“局域(yu)網(wang)”。該引腳(jiao)具有輸入輸出(chu)功(gong)能(neng)。一(yi)旦有某一(yi)路(lu)發生(sheng)故(gu)(gu)障(zhang),驅(qu)動(dong)(dong)(dong)芯(xin)片(pian)(pian)(pian)的(de)故(gu)(gu)障(zhang)管理系統(tong)立(li)即(ji)同(tong)步(bu)封(feng)鎖,同(tong)時向(xiang)控(kong)制(zhi)(zhi)器送出(chu)報警(jing)(jing)信(xin)號(hao)。短(duan)路(lu)保護(hu)迅速(su)有效,可大幅提(ti)高系統(tong)可靠性(xing)。當下(xia)管發生(sheng)過(guo)(guo)流(liu)時,即(ji)下(xia)管的(de)Vce探測點電(dian)(dian)壓(ya)超(chao)過(guo)(guo)其7V門限值,SY-FLT由(you)高變低(di),系統(tong)封(feng)鎖驅(qu)動(dong)(dong)(dong)輸出(chu),啟動(dong)(dong)(dong)軟(ruan)關(guan)斷過(guo)(guo)程,經測量時間(jian)約9.6微秒,同(tong)時向(xiang)單(dan)片(pian)(pian)(pian)機發出(chu)功(gong)率模塊短(duan)路(lu)故(gu)(gu)障(zhang)報警(jing)(jing)。軟(ruan)關(guan)斷結束后(hou),SY-FLT恢復(fu)高電(dian)(dian)平,同(tong)時在(zai)(zai)該路(lu)SY-FLT由(you)高變低(di)的(de)下(xia)降(jiang)沿,與此相連的(de)另一(yi)路(lu)驅(qu)動(dong)(dong)(dong)芯(xin)片(pian)(pian)(pian)同(tong)時封(feng)鎖輸出(chu),能(neng)夠有效防止(zhi)相間(jian)短(duan)路(lu)。另外驅(qu)動(dong)(dong)(dong)芯(xin)片(pian)(pian)(pian)有一(yi)個故(gu)(gu)障(zhang)清除(chu)信(xin)號(hao),當無過(guo)(guo)流(liu)信(xin)號(hao)時,可通過(guo)(guo)單(dan)片(pian)(pian)(pian)機快(kuai)速(su)恢復(fu)控(kong)制(zhi)(zhi)信(xin)號(hao),使得負載不會(hui)因(yin)為(wei)短(duan)時間(jian)保護(hu)而斷電(dian)(dian)。在(zai)(zai)帶大的(de)容性(xing)負載時輸出(chu)電(dian)(dian)壓(ya)只(zhi)是降(jiang)低(di)了一(yi)些,不會(hui)導致輸出(chu)斷電(dian)(dian)故(gu)(gu)障(zhang)。

3 結論

本文提出的(de)(de)慢降(jiang)柵壓技術和快(kuai)速開關SPWM脈沖信號的(de)(de)方式(shi)對電源(yuan)的(de)(de)主開關管進(jin)行(xing)雙重保護,有效地抑制(zhi)了(le)(le)不間斷交流(liu)電源(yuan)帶容性負載(zai)易(yi)出現(xian)斷電或損(sun)壞的(de)(de)問題(ti),解決了(le)(le)輸出斷電故障(zhang)。我們(men)研(yan)發的(de)(de)產品使用此設(she)計(ji)提高了(le)(le)質(zhi)量(liang),降(jiang)低了(le)(le)維護成本,得到(dao)了(le)(le)用戶的(de)(de)好(hao)評。

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