?????????????現代的電力電子技術無論對改造傳統工業(電力、機械、礦冶、交通、化工、輕紡等),還是對新建高技術產業(航天、激光、通信、機器人等)至關重要,從而已迅速發展成為一門獨立學科領域。它的應用領域幾乎涉及到國民經濟的各個工業部門,毫無疑問,它將成為本世紀乃至下世紀重要關鍵技術之一。近幾年西方發達的國家,盡管總體經濟的增長速度較慢,電力電子技術仍一直保持著每年百分之十幾的高速增長。 從歷(li)史上看(kan),每一代新型電(dian)(dian)(dian)(dian)力(li)電(dian)(dian)(dian)(dian)子器(qi)(qi)件的出現,總是帶來一場電(dian)(dian)(dian)(dian)力(li)電(dian)(dian)(dian)(dian)子技術(shu)的**。以(yi)功(gong)率器(qi)(qi)件為核心的現代電(dian)(dian)(dian)(dian)力(li)電(dian)(dian)(dian)(dian)子裝(zhuang)置,在整臺裝(zhuang)置中通常不超過總價(jia)值的20%~30%,但是,它對(dui)提高裝(zhuang)置的各項技術(shu)指標(biao)和(he)技術(shu)性能,卻(que)起著(zhu)十分(fen)重(zhong)要的作用。 眾所周(zhou)知,一個(ge)理(li)想的(de)功率器件,應(ying)當具(ju)(ju)有(you)下列理(li)想的(de)靜態(tai)和動態(tai)特性:在截止狀(zhuang)態(tai)時(shi)能承受高電壓(ya);在導通狀(zhuang)態(tai)時(shi),具(ju)(ju)有(you)大(da)電流和很低(di)的(de)壓(ya)降;在開關轉換時(shi),具(ju)(ju)有(you)短的(de)開、關時(shi)間,能承受高的(de)di/dt和dv/dt,以(yi)及(ji)具(ju)(ju)有(you)全(quan)控功能。 自(zi)從(cong)50年代,硅晶(jing)(jing)(jing)閘管(guan)(guan)(guan)問世(shi)(shi)以后,20多年來,功(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)半導(dao)(dao)體(ti)器(qi)(qi)(qi)件(jian)(jian)的(de)(de)(de)(de)研究工(gong)作者(zhe)為達到(dao)上述理想目標做出了(le)(le)不懈的(de)(de)(de)(de)努(nu)力,并(bing)已取得(de)了(le)(le)使(shi)世(shi)(shi)人(ren)矚目的(de)(de)(de)(de)成就(jiu)(jiu)。60年代后期,可(ke)關斷晶(jing)(jing)(jing)閘管(guan)(guan)(guan)GTO實(shi)現(xian)(xian)(xian)了(le)(le)門(men)(men)極(ji)(ji)可(ke)關斷功(gong)(gong)(gong)(gong)(gong)(gong)能(neng)(neng)(neng)(neng),并(bing)使(shi)斬(zhan)波工(gong)作頻(pin)率(lv)(lv)(lv)擴展到(dao)1kHz以上。70年代中(zhong)期,高功(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)晶(jing)(jing)(jing)體(ti)管(guan)(guan)(guan)和功(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv) MOSFET問世(shi)(shi),功(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)器(qi)(qi)(qi)件(jian)(jian)實(shi)現(xian)(xian)(xian)了(le)(le)場控功(gong)(gong)(gong)(gong)(gong)(gong)能(neng)(neng)(neng)(neng),打開了(le)(le)高頻(pin)應用的(de)(de)(de)(de)大門(men)(men)。80年代,絕緣柵(zha)門(men)(men)控雙(shuang)極(ji)(ji)型(xing)(xing)晶(jing)(jing)(jing)體(ti)管(guan)(guan)(guan) (IGBT)問世(shi)(shi),它綜(zong)合(he)(he)了(le)(le)功(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)MOSFET和雙(shuang)極(ji)(ji)型(xing)(xing)功(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)晶(jing)(jing)(jing)體(ti)管(guan)(guan)(guan)兩者(zhe)的(de)(de)(de)(de)功(gong)(gong)(gong)(gong)(gong)(gong)能(neng)(neng)(neng)(neng)。它的(de)(de)(de)(de)迅(xun)速發(fa)展,又激勵了(le)(le)人(ren)們(men)對綜(zong)合(he)(he)功(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)MOSFET和晶(jing)(jing)(jing)閘管(guan)(guan)(guan)兩者(zhe)功(gong)(gong)(gong)(gong)(gong)(gong)能(neng)(neng)(neng)(neng)的(de)(de)(de)(de)新型(xing)(xing)功(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)器(qi)(qi)(qi)件(jian)(jian)-MOSFET門(men)(men)控晶(jing)(jing)(jing)閘管(guan)(guan)(guan)的(de)(de)(de)(de)研究。因此,當前功(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)器(qi)(qi)(qi)件(jian)(jian)研究工(gong)作的(de)(de)(de)(de)重點(dian)主要集中(zhong)在(zai)研究現(xian)(xian)(xian)有功(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)器(qi)(qi)(qi)件(jian)(jian)的(de)(de)(de)(de)性能(neng)(neng)(neng)(neng)改進、MOS門(men)(men)控晶(jing)(jing)(jing)閘管(guan)(guan)(guan)以及采用新型(xing)(xing)半導(dao)(dao)體(ti)材料制(zhi)造新型(xing)(xing)的(de)(de)(de)(de)功(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)器(qi)(qi)(qi)件(jian)(jian)等(deng)。下面就(jiu)(jiu)近幾年來上述功(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)器(qi)(qi)(qi)件(jian)(jian)的(de)(de)(de)(de)*新發(fa)展加以綜(zong)述。 一(yi)、 功率(lv)晶閘管的*新發展 1.超大功率晶閘管 晶(jing)(jing)閘(zha)(zha)管(SCR)自問(wen)世以來(lai), 其功(gong)(gong)率容量提(ti)高(gao)了近(jin)3000倍。現在(zai)許多國(guo)家已(yi)能穩定生(sheng)產(chan)????mm、8kV /4kA的(de)(de)晶(jing)(jing)閘(zha)(zha)管。日本(ben)現在(zai)已(yi)投產(chan)8kV / 4kA和6kV /6kA的(de)(de)光觸(chu)發(fa)晶(jing)(jing)閘(zha)(zha)管(LTT)。美(mei)國(guo)和歐洲主要生(sheng)產(chan)電(dian)(dian)(dian)觸(chu)發(fa)晶(jing)(jing)閘(zha)(zha)管。近(jin)十幾(ji)年來(lai),由于自關斷(duan)器件的(de)(de)飛速發(fa)展,晶(jing)(jing)閘(zha)(zha)管的(de)(de)應用(yong)領域有所縮小,但是,由于它的(de)(de)高(gao)電(dian)(dian)(dian)壓(ya)、大(da)(da)電(dian)(dian)(dian)流(liu)特性,它在(zai)HVDC、靜止無功(gong)(gong)補償(SVC)、大(da)(da)功(gong)(gong)率直流(liu)電(dian)(dian)(dian)源及超大(da)(da)功(gong)(gong)率和高(gao)壓(ya)變頻調速應用(yong)方面仍(reng)占有十分重要的(de)(de)地位。預計在(zai)今(jin)后若干(gan)年內,晶(jing)(jing)閘(zha)(zha)管仍(reng)將在(zai)高(gao)電(dian)(dian)(dian)壓(ya)、大(da)(da)電(dian)(dian)(dian)流(liu)應用(yong)場合得到繼續發(fa)展。 現(xian)在(zai),許多生產商可(ke)提供額定開關功(gong)率36MVA ( 6kV/ 6kA)用的(de)高壓(ya)(ya)大電(dian)(dian)流GTO。傳統(tong)GTO的(de)典型(xing)的(de)關斷增(zeng)量僅(jin)為3~5。GTO關斷期(qi)間的(de)不(bu)均(jun)勻性引起的(de)“擠流效應”使(shi)其在(zai)關斷期(qi)間dv/dt必須(xu)限制在(zai)500~1kV/μs。為此,人們(men)不(bu)得(de)不(bu)使(shi)用體積大、昂(ang)貴的(de)吸(xi)收電(dian)(dian)路。另外它(ta)的(de)門極(ji)驅動電(dian)(dian)路較(jiao)復雜和要求(qiu)較(jiao)大的(de)驅動功(gong)率。但是(shi),高的(de)導(dao)通電(dian)(dian)流密度(du)、高的(de)阻(zu)(zu)斷電(dian)(dian)壓(ya)(ya)、阻(zu)(zu)斷狀態下高的(de)dv/dt耐量和有(you)可(ke)能在(zai)內部(bu)集成一個反并二極(ji)管(guan),這些突出的(de)優點仍使(shi)人們(men)對(dui)GTO感到興趣。到目(mu)前為止(zhi),在(zai)高壓(ya)(ya)(VBR > 3.3kV )、大功(gong)率(0.5~20MVA)牽引、工(gong)業和電(dian)(dian)力(li)逆(ni)變(bian)器(qi)(qi)中(zhong)應用得(de)*為普遍(bian)的(de)是(shi)門控功(gong)率半導(dao)體器(qi)(qi)件。目(mu)前,GTO的(de)*高研究水平為6in、6kV /6kA以及9kV/10kA。為了滿足電(dian)(dian)力(li)系統(tong)對(dui)1GVA以上的(de)三相(xiang)逆(ni)變(bian)功(gong)率電(dian)(dian)壓(ya)(ya)源(yuan)的(de)需要,近期(qi)很有(you)可(ke)能開發出10kA/12kV的(de)GTO,并有(you)可(ke)能解(jie)決30多個高壓(ya)(ya)GTO串聯(lian)的(de)技(ji)術,可(ke)望(wang)使(shi)電(dian)(dian)力(li)電(dian)(dian)子(zi)技(ji)術在(zai)電(dian)(dian)力(li)系統(tong)中(zhong)的(de)應用方面再上一個臺階。 2.脈沖功率(lv)閉合開關晶(jing)閘管 該(gai)器(qi)件特別適用(yong)于傳送極(ji)(ji)強的(de)(de)峰值功率(數(shu)MW)、極(ji)(ji)短(duan)的(de)(de)持續(xu)時間(數(shu)ns)的(de)(de)放電閉(bi)合開(kai)關應(ying)(ying)用(yong)場合,如:激(ji)光器(qi)、高強度照明、放電點火(huo)、電磁發(fa)射器(qi)和雷達調制器(qi)等。該(gai)器(qi)件能在數(shu)kV的(de)(de)高壓下快速開(kai)通,不需要放電電極(ji)(ji),具有很長(chang)的(de)(de)使用(yong)壽命,體積小(xiao)、價格比較低,可(ke)望取代目(mu)前尚在應(ying)(ying)用(yong)的(de)(de)高壓離子閘流(liu)管(guan)、引燃管(guan)、火(huo)花(hua)間隙開(kai)關或真(zhen)空開(kai)關等。 該器件獨(du)特(te)的(de)結(jie)構(gou)(gou)和工藝特(te)點(dian)是:門-陰極(ji)周界很長(chang)并(bing)形成(cheng)高度交織(zhi)的(de)結(jie)構(gou)(gou),門極(ji)面(mian)積(ji)占(zhan)(zhan)芯片總(zong)面(mian)積(ji)的(de)90%,而(er)陰極(ji)面(mian)積(ji)僅占(zhan)(zhan)10%;基區空穴-電(dian)子壽命(ming)很長(chang),門-陰極(ji)之間的(de)水平距離(li)小于一(yi)個擴散(san)長(chang)度。上述兩(liang)個結(jie)構(gou)(gou)特(te)點(dian)確保了該器件在開通瞬間,陰極(ji)面(mian)積(ji)能(neng)得到(dao)100%的(de)應(ying)用(yong)。此外(wai),該器件的(de)陰極(ji)電(dian)極(ji)采用(yong)較(jiao)厚的(de)金屬層,可承受瞬時峰(feng)值電(dian)流。 3.新(xin)型(xing)GTO器件-集(ji)成門極換流晶閘管 當前已(yi)有(you)兩種常(chang)規(gui)GTO的(de)替代品:高功(gong)率的(de)IGBT模(mo)塊、新型(xing)GTO派生器件(jian)-集成門極換流IGCT晶(jing)閘(zha)管。IGCT晶(jing)閘(zha)管是(shi)一種新型(xing)的(de)大功(gong)率器件(jian),與(yu)常(chang)規(gui)GTO晶(jing)閘(zha)管相比,它具有(you)許(xu)多(duo)優良的(de)特性,例如,不用緩(huan)沖(chong)電(dian)(dian)(dian)(dian)路能實(shi)現可靠關斷、存(cun)貯時(shi)間短(duan)、開通能力強、關斷門極電(dian)(dian)(dian)(dian)荷(he)少和(he)應用系統(包括所有(you)器件(jian)和(he)外圍(wei)部件(jian)如陽(yang)極電(dian)(dian)(dian)(dian)抗器和(he)緩(huan)沖(chong)電(dian)(dian)(dian)(dian)容器等)總的(de)功(gong)率損耗低等。 在(zai)(zai)上(shang)述(shu)這些特性中,優(you)良的(de)(de)(de)(de)(de)(de)開(kai)通和關(guan)(guan)(guan)斷(duan)(duan)能(neng)(neng)力是(shi)特別(bie)重要(yao)(yao)的(de)(de)(de)(de)(de)(de)方(fang)面(mian),因為在(zai)(zai)實際應(ying)用(yong)(yong)中,GTO的(de)(de)(de)(de)(de)(de)應(ying)用(yong)(yong)條件(jian)主(zhu)(zhu)要(yao)(yao)是(shi)受到這些開(kai)關(guan)(guan)(guan)特性的(de)(de)(de)(de)(de)(de)局限(xian)。眾所(suo)(suo)周知,GTO的(de)(de)(de)(de)(de)(de)關(guan)(guan)(guan)斷(duan)(duan)能(neng)(neng)力與(yu)其(qi)門(men)(men)(men)極驅動電(dian)(dian)(dian)(dian)路(lu)(lu)的(de)(de)(de)(de)(de)(de)性能(neng)(neng)關(guan)(guan)(guan)系極大,當門(men)(men)(men)極關(guan)(guan)(guan)斷(duan)(duan)電(dian)(dian)(dian)(dian)流(liu)(liu)的(de)(de)(de)(de)(de)(de)上(shang)升率(diGQ/dt)較高時(shi),GTO晶(jing)閘管則具有較高的(de)(de)(de)(de)(de)(de)關(guan)(guan)(guan)斷(duan)(duan)能(neng)(neng)力。一個4.5kV/4kA的(de)(de)(de)(de)(de)(de)IGCT與(yu)一個4.5kV/4kA的(de)(de)(de)(de)(de)(de)GTO的(de)(de)(de)(de)(de)(de)硅片(pian)(pian)(pian)尺(chi)寸(cun)類(lei)(lei)似(si),可是(shi)它(ta)(ta)(ta)能(neng)(neng)在(zai)(zai)高于(yu)6kA的(de)(de)(de)(de)(de)(de)情況下不用(yong)(yong)緩沖(chong)電(dian)(dian)(dian)(dian)路(lu)(lu)加(jia)以(yi)關(guan)(guan)(guan)斷(duan)(duan),它(ta)(ta)(ta)的(de)(de)(de)(de)(de)(de)diGQ/dt高達(da)6kA/μs。對于(yu)開(kai)通特性,門(men)(men)(men)極開(kai)通電(dian)(dian)(dian)(dian)流(liu)(liu)上(shang)升率(diG/dt)也非常(chang)重要(yao)(yao),可以(yi)借助于(yu)低的(de)(de)(de)(de)(de)(de)門(men)(men)(men)極驅動電(dian)(dian)(dian)(dian)路(lu)(lu)的(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)感(gan)比較容易實現。IGCT之所(suo)(suo)以(yi)具有上(shang)述(shu)這些優(you)良特性,是(shi)因為在(zai)(zai)器(qi)(qi)件(jian)結(jie)構(gou)上(shang)對GTO采取(qu)了一系列改進(jin)措施(shi)。圖1是(shi)IGCT管餅和芯片(pian)(pian)(pian)的(de)(de)(de)(de)(de)(de)外(wai)形照片(pian)(pian)(pian),芯片(pian)(pian)(pian)的(de)(de)(de)(de)(de)(de)基(ji)本圖形和結(jie)構(gou)與(yu)常(chang)規(gui)GTO類(lei)(lei)似(si),但是(shi)它(ta)(ta)(ta)除了采用(yong)(yong)了陽(yang)極短(duan)路(lu)(lu)型的(de)(de)(de)(de)(de)(de)逆導GTO結(jie)構(gou)以(yi)外(wai),主(zhu)(zhu)要(yao)(yao)是(shi)采用(yong)(yong)了特殊的(de)(de)(de)(de)(de)(de)環狀門(men)(men)(men)極,其(qi)引出(chu)端安排在(zai)(zai)器(qi)(qi)件(jian)的(de)(de)(de)(de)(de)(de)周邊(bian),特別(bie)是(shi)它(ta)(ta)(ta)的(de)(de)(de)(de)(de)(de)門(men)(men)(men)、陰極之間(jian)的(de)(de)(de)(de)(de)(de)距離要(yao)(yao)比常(chang)規(gui)GTO的(de)(de)(de)(de)(de)(de)小得多(duo),所(suo)(suo)以(yi)在(zai)(zai)門(men)(men)(men)極加(jia)以(yi)負偏壓實現關(guan)(guan)(guan)斷(duan)(duan)時(shi), 門(men)(men)(men)、陰極間(jian)可立即形成(cheng)耗(hao)盡層, 如(ru)圖2所(suo)(suo)示。這時(shi),從(cong)陽(yang)極注入基(ji)區的(de)(de)(de)(de)(de)(de)主(zhu)(zhu)電(dian)(dian)(dian)(dian)流(liu)(liu),則在(zai)(zai)關(guan)(guan)(guan)斷(duan)(duan)瞬間(jian)全(quan)部流(liu)(liu)入門(men)(men)(men)極,關(guan)(guan)(guan)斷(duan)(duan)增益為1, 從(cong)而(er)使器(qi)(qi)件(jian)迅速(su)關(guan)(guan)(guan)斷(duan)(duan)。不言而(er)喻, 關(guan)(guan)(guan)斷(duan)(duan)IGCT時(shi)需要(yao)(yao)提供與(yu)主(zhu)(zhu)電(dian)(dian)(dian)(dian)流(liu)(liu)相等的(de)(de)(de)(de)(de)(de)瞬時(shi)關(guan)(guan)(guan)斷(duan)(duan)電(dian)(dian)(dian)(dian)流(liu)(liu),這就要(yao)(yao)求包括(kuo)IGCT門(men)(men)(men)陰極在(zai)(zai)內的(de)(de)(de)(de)(de)(de)門(men)(men)(men)極驅動回路(lu)(lu)必須具有十分小的(de)(de)(de)(de)(de)(de)引線(xian)電(dian)(dian)(dian)(dian)感(gan)。實際上(shang),它(ta)(ta)(ta)的(de)(de)(de)(de)(de)(de)門(men)(men)(men)極和陰極之間(jian)的(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)感(gan)僅為常(chang)規(gui)GTO的(de)(de)(de)(de)(de)(de)1/10。 IGCT的(de)另一(yi)(yi)個特點是(shi)有一(yi)(yi)個極(ji)低(di)的(de)引(yin)線電(dian)感與(yu)(yu)管餅集成(cheng)在一(yi)(yi)起(qi)的(de)門(men)(men)極(ji)驅(qu)動(dong)器。IGCT用(yong)多層薄板(ban)(ban)狀的(de)襯板(ban)(ban)與(yu)(yu)主(zhu)門(men)(men)極(ji)驅(qu)動(dong)電(dian)路(lu)相接。門(men)(men)極(ji)驅(qu)電(dian)路(lu)則(ze)由襯板(ban)(ban)及許多并聯(lian)的(de)功(gong)率MOS管和放電(dian)電(dian)容器組(zu)成(cheng)。包括IGCT及其門(men)(men)極(ji)驅(qu)動(dong)電(dian)路(lu)在內的(de)總(zong)引(yin)線電(dian)感量可以(yi)減小到GTO的(de)1/100,表1是(shi)IGCT的(de)電(dian)特性參(can)數(shu)。 目前,4.5kV (1.9kV/2.7kV 直流鏈(lian)(lian))及 5.5kV (3.3kV直流鏈(lian)(lian))、 275A 有(you)效硅面(mian)積小(xiao)、低(di)損耗、快速開關這些(xie)優(you)(you)點保證了(le)IGCT能可(ke)靠、高(gao)(gao)(gao)效率(lv)(lv)地用于(yu)300kVA~10MVA變流器(qi),而不(bu)需要串聯或并聯。在(zai)串聯時,逆(ni)變器(qi)功(gong)率(lv)(lv)可(ke)擴展到100MVA。雖然高(gao)(gao)(gao)功(gong)率(lv)(lv)的(de)IGBT模塊(kuai)具有(you)一(yi)(yi)些(xie)優(you)(you)良的(de)特性,如能實現di/dt和dv/dt的(de)有(you)源(yuan)(yuan)控制、有(you)源(yuan)(yuan)箝位、易于(yu)實現短路(lu)電流保護(hu)(hu)和有(you)源(yuan)(yuan)保護(hu)(hu)等(deng)。但(dan)因存在(zai)著導通高(gao)(gao)(gao)損耗、硅有(you)效面(mian)積低(di)利用率(lv)(lv)、損壞后造成開路(lu)以及無長期可(ke)靠運行(xing)數據等(deng)缺點,限制了(le)高(gao)(gao)(gao)功(gong)率(lv)(lv)IGBT模塊(kuai)在(zai)高(gao)(gao)(gao)功(gong)率(lv)(lv)低(di)頻變流器(qi)中的(de)實際應(ying)用。因此在(zai)大功(gong)率(lv)(lv)MCT未(wei)問世(shi)以前(qian),IGCT可(ke)望(wang)成為高(gao)(gao)(gao)功(gong)率(lv)(lv)高(gao)(gao)(gao)電壓低(di)頻變流器(qi)的(de)優(you)(you)選功(gong)率(lv)(lv)器(qi)件之一(yi)(yi)。 ? |