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變頻器的現狀及其未來的技術發展方向 |
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作者：admin 來源：本站 發表時間：2013/3/23 9:23:16 點擊：3109
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變(bian)頻(pin)技(ji)術(shu)(shu)的迅速發展是(shi)建立在電(dian)力(li)電(dian)子(zi)技(ji)術(shu)(shu)的創新(xin)、電(dian)力(li)電(dian)子(zi)器(qi)件及(ji)材料的開發及(ji)器(qi)件制造工藝(yi)水平提高(gao)基(ji)礎之(zhi)上的，尤(you)其是(shi)高(gao)壓大(da)(da)容量絕緣(yuan)柵雙極(ji)晶(jing)體管IGBT、集成(cheng)門(men)極(ji)換(huan)流晶(jing)閘(zha)管工IGCT器(qi)件的成(cheng)功開發，使大(da)(da)功率(lv)變(bian)頻(pin)技(ji)術(shu)(shu)得(de)以迅速發展，性能日益完善。目(mu)前市場上新(xin)型變(bian)頻(pin)器(qi)品牌繁多(duo)，各有(you)千秋。通過分(fen)析發現，這(zhe)類變(bian)頻(pin)器(qi)有(you)許多(duo)共(gong)同點。下面(mian)對變(bian)頻(pin)器(qi)的現狀(zhuang)及(ji)其未(wei)來(lai)的技(ji)術(shu)(shu)發展方向(xiang)進行分(fen)析介紹。 1.變頻器的市場情況： 我國(guo)(guo)(guo)(guo)50%～60%的(de)(de)(de)(de)發電(dian)(dian)(dian)量(liang)用于交流電(dian)(dian)(dian)動(dong)機(ji)，而(er)容量(liang)在(zai)(zai)(zai)(zai)3kw以(yi)(yi)上，額定電(dian)(dian)(dian)壓一般為3～10kV的(de)(de)(de)(de)電(dian)(dian)(dian)動(dong)機(ji)占(zhan)電(dian)(dian)(dian)動(dong)機(ji)總裝機(ji)容量(liang)的(de)(de)(de)(de)40%～50%。由(you)于我國(guo)(guo)(guo)(guo)中(zhong)(zhong)壓變(bian)頻(pin)技術仍(reng)沒有(you)形成產業(ye)(ye)化(hua)，落(luo)后于國(guo)(guo)(guo)(guo)外發達國(guo)(guo)(guo)(guo)家，因此這(zhe)部(bu)分電(dian)(dian)(dian)動(dong)機(ji)在(zai)(zai)(zai)(zai)負載(zai)工(gong)況變(bian)化(hua)時，缺少(shao)經濟(ji)可靠的(de)(de)(de)(de)調速(su)手段，每天都(dou)在(zai)(zai)(zai)(zai)浪費著(zhu)(zhu)大量(liang)的(de)(de)(de)(de)電(dian)(dian)(dian)能，因此國(guo)(guo)(guo)(guo)內(nei)(nei)潛在(zai)(zai)(zai)(zai)著(zhu)(zhu)巨大的(de)(de)(de)(de)中(zhong)(zhong)壓大功(gong)率(lv)變(bian)頻(pin)器(qi)(qi)市(shi)(shi)場。國(guo)(guo)(guo)(guo)家計委預計在(zai)(zai)(zai)(zai)今后十五年(nian)內(nei)(nei)，使我國(guo)(guo)(guo)(guo)變(bian)頻(pin)器(qi)(qi)總需求的(de)(de)(de)(de)投資額在(zai)(zai)(zai)(zai)500億元以(yi)(yi)上，而(er)其中(zhong)(zhong)60%～70%是中(zhong)(zhong)壓大功(gong)率(lv)變(bian)頻(pin)器(qi)(qi)。我國(guo)(guo)(guo)(guo)的(de)(de)(de)(de)高壓變(bian)頻(pin)器(qi)(qi)市(shi)(shi)場具有(you)其特(te)殊性，包括：(1)行(xing)(xing)業(ye)(ye)性很強，主要集(ji)中(zhong)(zhong)在(zai)(zai)(zai)(zai)冶金(jin)、電(dian)(dian)(dian)力(li)、供水、石(shi)油、化(hua)工(gong)、煤(mei)炭等行(xing)(xing)業(ye)(ye)。在(zai)(zai)(zai)(zai)工(gong)業(ye)(ye)用電(dian)(dian)(dian)中(zhong)(zhong)石(shi)油、煤(mei)炭等能源行(xing)(xing)業(ye)(ye)耗電(dian)(dian)(dian)占(zhan)22.34%；化(hua)工(gong)占(zhan)14.73%；冶金(jin)占(zhan)14.18%；機(ji)械建材占(zhan)10.96%；供水占(zhan)10.53%。(2)目前全國(guo)(guo)(guo)(guo)各(ge)行(xing)(xing)業(ye)(ye)中(zhong)(zhong)，只有(you)少(shao)數(shu)企業(ye)(ye)的(de)(de)(de)(de)高壓電(dian)(dian)(dian)機(ji)使用了(le)調速(su)方(fang)式，市(shi)(shi)場空白點多。(3)高壓變(bian)頻(pin)器(qi)(qi)屬投資類(lei)設(she)備，主要用于節能和改善生(sheng)產工(gong)藝。用戶是否購買此類(lei)設(she)備與政(zheng)府的(de)(de)(de)(de)政(zheng)策導(dao)向關系很大。如(ru)政(zheng)府推(tui)廣力(li)度(du)較(jiao)大，市(shi)(shi)場啟動(dong)會快一些(xie)，反之則慢(man)。另一方(fang)面市(shi)(shi)場還受國(guo)(guo)(guo)(guo)際、國(guo)(guo)(guo)(guo)內(nei)(nei)經濟(ji)大環(huan)境的(de)(de)(de)(de)影響(xiang)(xiang)以(yi)(yi)及國(guo)(guo)(guo)(guo)內(nei)(nei)某些(xie)行(xing)(xing)業(ye)(ye)的(de)(de)(de)(de)整體經濟(ji)效(xiao)益好壞的(de)(de)(de)(de)影響(xiang)(xiang)。因此在(zai)(zai)(zai)(zai)未來市(shi)(shi)場發展(zhan)過程(cheng)中(zhong)(zhong)仍(reng)存在(zai)(zai)(zai)(zai)著(zhu)(zhu)一些(xie)不確(que)定的(de)(de)(de)(de)因素。(4)海外公司的(de)(de)(de)(de)知(zhi)名品牌產品大舉進入我國(guo)(guo)(guo)(guo)市(shi)(shi)場的(de)(de)(de)(de)可能性較(jiao)大，各(ge)方(fang)應有(you)所準備。 2.變頻器的變頻技術的現狀 交一(yi)交變(bian)(bian)頻(pin)(pin)是早期變(bian)(bian)頻(pin)(pin)的(de)主要形(xing)式，適(shi)應于低轉(zhuan)速大容量的(de)電(dian)動機負(fu)載。其主電(dian)路開關器(qi)件處(chu)于自然關斷狀態，不存在強(qiang)迫換流問題(ti)，所(suo)以第一(yi)代(dai)電(dian)力電(dian)子器(qi)件—晶閘(zha)管就能完全滿足它的(de)要求。由于其技術成熟，在國內(nei)開發研制(zhi)(zhi)也最多，目前在國內(nei)仍有(you)一(yi)定的(de)市場。交一(yi)交變(bian)(bian)頻(pin)(pin)在其主接線中需要大量的(de)晶閘(zha)管，結構(gou)復雜，維護工(gong)作量較(jiao)大，并(bing)因采用(yong)移(yi)相控(kong)制(zhi)(zhi)方式，功(gong)率因數較(jiao)低，一(yi)般僅有(you)0.6～0.7，而且(qie)諧(xie)波(bo)成分大，需要無功(gong)補償和(he)濾波(bo)裝(zhuang)置，使得總的(de)造價提高(gao)。 交一(yi)(yi)直一(yi)(yi)交變頻采(cai)用了(le)多(duo)種(zhong)拓撲結構(gou)，如(ru)中(zhong)(zhong)一(yi)(yi)低(di)一(yi)(yi)中(zhong)(zhong)方(fang)(fang)式，其(qi)實質上還是低(di)壓(ya)(ya)變頻，只不過從(cong)電(dian)網和電(dian)動機(ji)兩端來看是高壓(ya)(ya)。由(you)于其(qi)存在(zai)著(zhu)中(zhong)(zhong)間低(di)壓(ya)(ya)環(huan)節(jie)，所以(yi)具有(you)電(dian)流大(da)、結構(gou)復雜、效率(lv)低(di)、可靠性差等(deng)缺點。由(you)于其(qi)發(fa)展(zhan)較(jiao)早，技術也比較(jiao)成(cheng)熟，所以(yi)目(mu)前(qian)仍(reng)廣(guang)泛應用。隨著(zhu)中(zhong)(zhong)壓(ya)(ya)變頻技術的(de)發(fa)展(zhan)，特別是新型(xing)大(da)功(gong)率(lv)可關斷器件的(de)研制成(cheng)功(gong)，中(zhong)(zhong)一(yi)(yi)低(di)一(yi)(yi)中(zhong)(zhong)方(fang)(fang)式具有(you)被逐步淘汰的(de)趨勢(shi)。而(er)直接中(zhong)(zhong)壓(ya)(ya)變頻方(fang)(fang)式，因沒(mei)有(you)中(zhong)(zhong)間的(de)低(di)壓(ya)(ya)環(huan)節(jie)，結構(gou)上有(you)著(zhu)廣(guang)闊(kuo)的(de)發(fa)展(zhan)前(qian)景。 變(bian)頻(pin)器的(de)(de)(de)(de)逆(ni)變(bian)器普遍(bian)采(cai)用(yong)(yong)大功(gong)率場效應管MOSET、大功(gong)率晶體管GTR、可(ke)關斷晶閘管GTO等的(de)(de)(de)(de)自關斷元件(jian)，其中GTR應用(yong)(yong)最為普遍(bian)。但是在調制策略發展和(he)(he)要(yao)求(qiu)逆(ni)變(bian)器輸出(chu)諧波分量更小(xiao)的(de)(de)(de)(de)情況下，必(bi)須提高(gao)(gao)開(kai)(kai)(kai)關頻(pin)率，為此，GTR滿足不(bu)了這個要(yao)求(qiu)，于(yu)是開(kai)(kai)(kai)發出(chu)了一(yi)種新元件(jian)IGBT。IGBT的(de)(de)(de)(de)全稱是絕緣柵雙(shuang)極(ji)晶體管，是一(yi)種把(ba)MOSET與GTR巧(qiao)妙結合(he)在一(yi)起的(de)(de)(de)(de)電(dian)(dian)壓(ya)(ya)(ya)型雙(shuang)極(ji)/M05復合(he)器件(jian)，IGBT具有輸入阻抗高(gao)(gao)、開(kai)(kai)(kai)關速(su)度快、元件(jian)損耗小(xiao)、驅(qu)動(dong)電(dian)(dian)路簡(jian)單(dan)、驅(qu)動(dong)功(gong)率小(xiao)、極(ji)限溫度高(gao)(gao)、熱阻小(xiao)、飽和(he)(he)壓(ya)(ya)(ya)降和(he)(he)電(dian)(dian)阻低(di)、電(dian)(dian)流容量大、抗浪涌能力(li)強、安全區寬、并(bing)聯容易、穩(wen)定可(ke)靠及模塊(kuai)化(hua)等一(yi)系列優點，是一(yi)種極(ji)理想(xiang)的(de)(de)(de)(de)開(kai)(kai)(kai)關元件(jian)。目(mu)前，電(dian)(dian)流2400A、電(dian)(dian)壓(ya)(ya)(ya)3300V、開(kai)(kai)(kai)關頻(pin)率40kHz的(de)(de)(de)(de)IGBT已在小(xiao)、中、大功(gong)率范圍內使用(yong)(yong)。IGBT不(bu)僅用(yong)(yong)于(yu)500V以(yi)下低(di)壓(ya)(ya)(ya)變(bian)頻(pin)器，還可(ke)以(yi)用(yong)(yong)于(yu)IOOOV以(yi)上高(gao)(gao)壓(ya)(ya)(ya)變(bian)頻(pin)器以(yi)驅(qu)動(dong)高(gao)(gao)壓(ya)(ya)(ya)電(dian)(dian)動(dong)機(ji)。此類中壓(ya)(ya)(ya)、高(gao)(gao)壓(ya)(ya)(ya)變(bian)頻(pin)器采(cai)用(yong)(yong)多(duo)電(dian)(dian)平逆(ni)變(bian)器輸出(chu)高(gao)(gao)壓(ya)(ya)(ya)，也可(ke)用(yong)(yong)變(bian)壓(ya)(ya)(ya)器降壓(ya)(ya)(ya)～低(di)壓(ya)(ya)(ya)變(bian)頻(pin)器一(yi)變(bian)壓(ya)(ya)(ya)器升壓(ya)(ya)(ya)的(de)(de)(de)(de)方式。由于(yu)IGBT具有性能特好的(de)(de)(de)(de)優勢(shi)，預計(ji)近十(shi)年內不(bu)會被新開(kai)(kai)(kai)發的(de)(de)(de)(de)元件(jian)所取代。 變頻器的技術發展動向 1.單元串聯多電平技術 單元(yuan)串(chuan)(chuan)聯(lian)多電(dian)(dian)(dian)(dian)(dian)平(ping)(ping)形(xing)(xing)式在(zai)諧(xie)波(bo)(bo)(bo)、效率(lv)(lv)和(he)功率(lv)(lv)因數等(deng)方(fang)面(mian)存在(zai)著優(you)勢，在(zai)不要求四象限運(yun)行時有(you)著較(jiao)廣泛的應(ying)用(yong)前景。其中三(san)(san)(san)(san)電(dian)(dian)(dian)(dian)(dian)平(ping)(ping)控制具有(you)許(xu)多優(you)點(dian)，包括：(1)采(cai)用(yong)三(san)(san)(san)(san)電(dian)(dian)(dian)(dian)(dian)平(ping)(ping)拓(tuo)撲(pu)能有(you)效地解(jie)決電(dian)(dian)(dian)(dian)(dian)力電(dian)(dian)(dian)(dian)(dian)子器件(jian)耐壓(ya)(ya)不高(gao)的問(wen)題，適(shi)用(yong)于(yu)高(gao)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)大(da)(da)功率(lv)(lv)。(2)三(san)(san)(san)(san)電(dian)(dian)(dian)(dian)(dian)平(ping)(ping)拓(tuo)撲(pu)單個(ge)(ge)橋能輸(shu)出三(san)(san)(san)(san)種(zhong)電(dian)(dian)(dian)(dian)(dian)平(ping)(ping)(+ud/2、-ud/2、0)，線(相(xiang))電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)有(you)更(geng)多的階梯來(lai)模擬(ni)正弦波(bo)(bo)(bo)，使(shi)(shi)輸(shu)出波(bo)(bo)(bo)形(xing)(xing)失真(zhen)度減(jian)少(shao)(shao)，諧(xie)波(bo)(bo)(bo)大(da)(da)大(da)(da)減(jian)少(shao)(shao)。(3)多級電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)階梯波(bo)(bo)(bo)減(jian)少(shao)(shao)了du/dt，使(shi)(shi)得(de)對電(dian)(dian)(dian)(dian)(dian)機繞組絕緣沖擊減(jian)小(xiao)。(4)三(san)(san)(san)(san)電(dian)(dian)(dian)(dian)(dian)平(ping)(ping)PWM方(fang)法把第一組諧(xie)波(bo)(bo)(bo)分(fen)布帶(dai)移至2倍開(kai)(kai)關(guan)(guan)頻率(lv)(lv)的頻帶(dai)區，利用(yong)電(dian)(dian)(dian)(dian)(dian)機繞組電(dian)(dian)(dian)(dian)(dian)感能較(jiao)好地抑制高(gao)次(ci)諧(xie)波(bo)(bo)(bo)對電(dian)(dian)(dian)(dian)(dian)機的影(ying)響。采(cai)用(yong)三(san)(san)(san)(san)電(dian)(dian)(dian)(dian)(dian)平(ping)(ping)PWM方(fang)法，每個(ge)(ge)功率(lv)(lv)單元(yuan)的IGBT開(kai)(kai)關(guan)(guan)頻率(lv)(lv)為600Hz，若每相(xiang)5個(ge)(ge)功率(lv)(lv)單元(yuan)串(chuan)(chuan)聯(lian)時，等(deng)效的輸(shu)出相(xiang)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)開(kai)(kai)關(guan)(guan)頻率(lv)(lv)為6kHz，可以(yi)降低開(kai)(kai)關(guan)(guan)損耗，提(ti)高(gao)變頻器效率(lv)(lv)，這種(zhong)變頻器可適(shi)用(yong)于(yu)任何普(pu)通(tong)的高(gao)壓(ya)(ya)電(dian)(dian)(dian)(dian)(dian)動機，且(qie)不必降額使(shi)(shi)用(yong)。雖(sui)然采(cai)用(yong)這種(zhong)主電(dian)(dian)(dian)(dian)(dian)路拓(tuo)撲(pu)結構(gou)會(hui)使(shi)(shi)器件(jian)的數量(liang)(liang)增加，但由(you)于(yu)驅動功率(lv)(lv)下降，開(kai)(kai)關(guan)(guan)頻率(lv)(lv)較(jiao)低且(qie)不必采(cai)用(yong)均壓(ya)(ya)電(dian)(dian)(dian)(dian)(dian)路，使(shi)(shi)系統(tong)在(zai)效率(lv)(lv)方(fang)面(mian)仍有(you)較(jiao)大(da)(da)的優(you)勢，一般可達97%。并且(qie)，由(you)于(yu)采(cai)用(yong)模塊化結構(gou)，所有(you)功率(lv)(lv)單元(yuan)可以(yi)互換，維修也比較(jiao)方(fang)便。(5)三(san)(san)(san)(san)電(dian)(dian)(dian)(dian)(dian)平(ping)(ping)拓(tuo)撲(pu)能產(chan)生3*3*3=27種(zhong)空間電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)矢量(liang)(liang)，可以(yi)帶(dai)來(lai)諧(xie)波(bo)(bo)(bo)消除(chu)算(suan)法的自由(you)度，可以(yi)得(de)到很好的輸(shu)出波(bo)(bo)(bo)形(xing)(xing)。 2.功率母線技術 在(zai)電(dian)(dian)(dian)力電(dian)(dian)(dian)子(zi)技(ji)術及應用裝置向高(gao)頻化發展的(de)(de)(de)(de)(de)今天(tian)，系統(tong)中特別是連接線(xian)的(de)(de)(de)(de)(de)寄生(sheng)參數產生(sheng)巨(ju)大(da)的(de)(de)(de)(de)(de)電(dian)(dian)(dian)應力，己成為威脅電(dian)(dian)(dian)力電(dian)(dian)(dian)子(zi)裝置可靠性的(de)(de)(de)(de)(de)重要因(yin)素。從直(zhi)流儲能電(dian)(dian)(dian)容至逆(ni)變器的(de)(de)(de)(de)(de)器件(jian)之間的(de)(de)(de)(de)(de)直(zhi)流母(mu)線(xian)上(shang)的(de)(de)(de)(de)(de)寄生(sheng)電(dian)(dian)(dian)感在(zai)通常的(de)(de)(de)(de)(de)硬開(kai)關逆(ni)變器中，由于瞬時(shi)切換時(shi)的(de)(de)(de)(de)(de)過(guo)電(dian)(dian)(dian)壓，會(hui)使器件(jian)過(guo)熱，甚至有時(shi)使逆(ni)變器失控并超過(guo)器件(jian)的(de)(de)(de)(de)(de)額定安全工作區而(er)損壞，限制(zhi)了(le)開(kai)關工作頻率的(de)(de)(de)(de)(de)提高(gao)。功率母(mu)線(xian)按其結構包括(kuo)： (1)電纜絞線(xian)(xian)是最常(chang)用的(de)(de)(de)(de)傳統功率(lv)母線(xian)(xian)，價廉(lian)簡(jian)易，但在IGBT逆變器中，由于電纜線(xian)(xian)的(de)(de)(de)(de)自(zi)感(gan)大，與圓截(jie)面導線(xian)(xian)相比，扁平(ping)母線(xian)(xian)的(de)(de)(de)(de)自(zi)感(gan)只(zhi)有圓導線(xian)(xian)的(de)(de)(de)(de)1/3一(yi)1/2，而(er)所占(zhan)的(de)(de)(de)(de)體積只(zhi)有它的(de)(de)(de)(de)1/10一(yi)1/2。 (2)印(yin)刷電(dian)(dian)路(lu)板(ban)(ban)母(mu)線(xian)主要用于小電(dian)(dian)流(liu)(liu)(liu)逆變器，但當母(mu)線(xian)直流(liu)(liu)(liu)電(dian)(dian)流(liu)(liu)(liu)達(da)到(dao)150A時(shi)，要求電(dian)(dian)路(lu)板(ban)(ban)的(de)(de)(de)復銅(tong)層很厚，造價太高(gao)，另外(wai)用來連接多層導線(xian)板(ban)(ban)的(de)(de)(de)穿孔不但占據較大的(de)(de)(de)空間，而且會影(ying)響整機的(de)(de)(de)可靠性。 (3)裸銅板母線(平(ping)面并(bing)行(xing)母線)是(shi)一種工業(ye)上廣(guang)泛(fan)應用的IGBT模塊饋電系統的傳統母線形式，其缺(que)點是(shi)并(bing)行(xing)母線的互感較大。 (4)支架式(shi)母(mu)線(xian)如果(guo)將正直(zhi)流(liu)母(mu)線(xian)銅板放置在負直(zhi)流(liu)母(mu)線(xian)板上方，中間用一層薄絕緣材料(liao)隔開的(de)方法(fa)來制作母(mu)線(xian)，由于磁場的(de)相互抵消(xiao)，可以最大限度(du)地(di)降低互感，但(dan)其工藝復雜，不宜規模化生產(chan)。 基于上述幾種(zhong)功(gong)(gong)率(lv)母(mu)(mu)(mu)(mu)線(xian)(xian)(xian)(xian)(xian)都(dou)存(cun)在著不(bu)同(tong)(tong)(tong)的(de)(de)(de)(de)缺(que)點，為此開發出了(le)迭層(ceng)功(gong)(gong)率(lv)母(mu)(mu)(mu)(mu)線(xian)(xian)(xian)(xian)(xian)。迭層(ceng)功(gong)(gong)率(lv)母(mu)(mu)(mu)(mu)線(xian)(xian)(xian)(xian)(xian)是基于電(dian)(dian)磁場(chang)理(li)論(lun)，把連(lian)線(xian)(xian)(xian)(xian)(xian)做(zuo)成(cheng)(cheng)扁平截面(mian)，在同(tong)(tong)(tong)樣的(de)(de)(de)(de)截面(mian)下，做(zuo)得越(yue)薄(bo)越(yue)寬，它(ta)的(de)(de)(de)(de)寄(ji)生電(dian)(dian)感越(yue)小，相(xiang)(xiang)鄰導線(xian)(xian)(xian)(xian)(xian)內流過相(xiang)(xiang)反(fan)的(de)(de)(de)(de)電(dian)(dian)流，其磁場(chang)抵(di)消，也可(ke)使(shi)寄(ji)生電(dian)(dian)感減(jian)小。迭層(ceng)功(gong)(gong)率(lv)母(mu)(mu)(mu)(mu)線(xian)(xian)(xian)(xian)(xian)是以又薄(bo)又寬的(de)(de)(de)(de)銅(tong)排(pai)形(xing)式(shi)迭放在一(yi)起(qi)，各層(ceng)之(zhi)(zhi)(zhi)間用很薄(bo)的(de)(de)(de)(de)高絕緣(yuan)強(qiang)度(du)的(de)(de)(de)(de)材料(liao)熱壓(ya)成(cheng)(cheng)一(yi)體，整(zheng)個母(mu)(mu)(mu)(mu)線(xian)(xian)(xian)(xian)(xian)極之(zhi)(zhi)(zhi)間的(de)(de)(de)(de)距(ju)離(li)均勻一(yi)致(zhi)，以減(jian)少互感，各層(ceng)銅(tong)排(pai)都(dou)在所(suo)需要的(de)(de)(de)(de)端子(zi)位(wei)置(zhi)處同(tong)(tong)(tong)其他層(ceng)可(ke)靠絕緣(yuan)地(di)引出，使(shi)所(suo)具有不(bu)同(tong)(tong)(tong)電(dian)(dian)位(wei)的(de)(de)(de)(de)端子(zi)表露在同(tong)(tong)(tong)一(yi)平面(mian)上，以便于把主電(dian)(dian)路中的(de)(de)(de)(de)所(suo)有器件(jian)與之(zhi)(zhi)(zhi)相(xiang)(xiang)連(lian)。這種(zhong)整(zheng)體的(de)(de)(de)(de)迭層(ceng)功(gong)(gong)率(lv)母(mu)(mu)(mu)(mu)線(xian)(xian)(xian)(xian)(xian)結構(gou)，可(ke)承受(shou)數百千克的(de)(de)(de)(de)切應力，其導電(dian)(dian)極之(zhi)(zhi)(zhi)間可(ke)承受(shou)數千伏的(de)(de)(de)(de)電(dian)(dian)壓(ya)。使(shi)用迭層(ceng)功(gong)(gong)率(lv)母(mu)(mu)(mu)(mu)線(xian)(xian)(xian)(xian)(xian)將IGBT和整(zheng)流管等模(mo)塊、散熱器、電(dian)(dian)容器及柵極驅動電(dian)(dian)路組合在一(yi)起(qi)，迭層(ceng)功(gong)(gong)率(lv)母(mu)(mu)(mu)(mu)線(xian)(xian)(xian)(xian)(xian)與器件(jian)之(zhi)(zhi)(zhi)間的(de)(de)(de)(de)連(lian)接是用不(bu)同(tong)(tong)(tong)的(de)(de)(de)(de)端子(zi)和插接件(jian)等來完(wan)成(cheng)(cheng)的(de)(de)(de)(de)，使(shi)相(xiang)(xiang)連(lian)接的(de)(de)(de)(de)接觸表面(mian)與母(mu)(mu)(mu)(mu)線(xian)(xian)(xian)(xian)(xian)之(zhi)(zhi)(zhi)間的(de)(de)(de)(de)接觸電(dian)(dian)阻非常小，也使(shi)得寄(ji)生電(dian)(dian)感成(cheng)(cheng)數量級地(di)減(jian)小，從而使(shi)Ldi/dt的(de)(de)(de)(de)過電(dian)(dian)壓(ya)應力降(jiang)至最(zui)低，保證電(dian)(dian)力電(dian)(dian)子(zi)裝置(zhi)工作在最(zui)佳狀態(tai)。 3.微(wei)機(ji)控制和人工(gong)智能技術(shu) 采用(yong)微(wei)機控制(zhi)技術可以(yi)對變頻器(qi)進行控制(zhi)和保護。在控制(zhi)方面(mian)： (1)計算確定開(kai)關(guan)元件的開(kai)通和關(guan)斷時(shi)刻，使逆(ni)變器按(an)調制策略輸出要求的電壓。 (2)通(tong)過不(bu)同(tong)的(de)編碼實現多種傳動(dong)調(diao)速功能。如(ru)各(ge)種頻率的(de)設(she)(she)(she)定(ding)和(he)執行、啟動(dong)、運(yun)(yun)行方式選(xuan)擇、轉矩控制設(she)(she)(she)定(ding)與運(yun)(yun)行、加(jia)減速設(she)(she)(she)計與運(yun)(yun)行、制動(dong)方式設(she)(she)(she)定(ding)和(he)執行等。 (3)通(tong)過(guo)(guo)接口電(dian)(dian)(dian)(dian)路(lu)、外(wai)部傳(chuan)感(gan)器、微機構成(cheng)(cheng)調速傳(chuan)動系(xi)統。在保(bao)(bao)護(hu)方面，在外(wai)部傳(chuan)感(gan)器及I/0電(dian)(dian)(dian)(dian)路(lu)配合下，構成(cheng)(cheng)完善(shan)的檢(jian)測保(bao)(bao)護(hu)系(xi)統，可完成(cheng)(cheng)多種自診(zhen)斷(duan)保(bao)(bao)護(hu)方案。保(bao)(bao)護(hu)功能(neng)包括：(1)主電(dian)(dian)(dian)(dian)路(lu)、控(kong)制電(dian)(dian)(dian)(dian)路(lu)的欠壓(ya)、過(guo)(guo)電(dian)(dian)(dian)(dian)壓(ya)保(bao)(bao)護(hu)；(2)輸出(chu)電(dian)(dian)(dian)(dian)流的欠電(dian)(dian)(dian)(dian)流、過(guo)(guo)電(dian)(dian)(dian)(dian)流保(bao)(bao)護(hu)；(3)電(dian)(dian)(dian)(dian)動機或逆(ni)變器的過(guo)(guo)載保(bao)(bao)護(hu)；(4)制動電(dian)(dian)(dian)(dian)阻的過(guo)(guo)熱保(bao)(bao)護(hu)；(5)失(shi)速保(bao)(bao)護(hu)。 采(cai)用人工智能(neng)(neng)技術(shu)對(dui)(dui)(dui)變(bian)頻器(qi)進行(xing)(xing)故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)診(zhen)斷(duan)(duan)(duan)，構(gou)成(cheng)故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)診(zhen)斷(duan)(duan)(duan)系統(tong)，該系統(tong)由監控、檢測(ce)、知識庫(ku)(故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)模式知識庫(ku)或(huo)故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)診(zhen)斷(duan)(duan)(duan)專家系統(tong)知識庫(ku))、推理機(ji)(ji)構(gou)、人機(ji)(ji)對(dui)(dui)(dui)話接口和數據庫(ku)組成(cheng)，不(bu)僅在(zai)故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)發(fa)生(sheng)(sheng)后能(neng)(neng)準(zhun)確指出故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)性質、部(bu)位，且在(zai)故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)發(fa)生(sheng)(sheng)前(qian)(qian)也能(neng)(neng)預測(ce)發(fa)生(sheng)(sheng)故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)的可能(neng)(neng)性。在(zai)變(bian)頻器(qi)啟(qi)動(dong)前(qian)(qian)對(dui)(dui)(dui)診(zhen)斷(duan)(duan)(duan)系統(tong)本身及(ji)(ji)變(bian)頻器(qi)主電(dian)路(lu)(包(bao)括電(dian)源)、控制(zhi)系統(tong)等進行(xing)(xing)一次(ci)診(zhen)斷(duan)(duan)(duan)清查(cha)隱(yin)患。若(ruo)發(fa)現(xian)(xian)故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)現(xian)(xian)象(xiang)則(ze)調(diao)用知識庫(ku)推理、判斷(duan)(duan)(duan)故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)原因并顯示不(bu)能(neng)(neng)開(kai)機(ji)(ji)，如(ru)無故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)則(ze)顯示可以開(kai)機(ji)(ji)。開(kai)機(ji)(ji)后，實時檢測(ce)診(zhen)斷(duan)(duan)(duan)。工作時對(dui)(dui)(dui)各檢測(ce)點進行(xing)(xing)循(xun)環查(cha)詢，存儲(chu)數據并不(bu)斷(duan)(duan)(duan)刷新(xin)。若(ruo)發(fa)現(xian)(xian)數據越限，則(ze)認為可能(neng)(neng)發(fa)生(sheng)(sheng)故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)，立(li)即定(ding)向追蹤。若(ruo)幾次(ci)檢查(cha)結果(guo)相同(tong)，說明(ming)確實出了故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)，于是調(diao)用知識庫(ku)進行(xing)(xing)分析推理，確定(ding)是何種(zhong)故(gu)(gu)(gu)(gu)(gu)障(zhang)(zhang)(zhang)及(ji)(ji)其部(bu)位，顯示出來，嚴重(zhong)時則(ze)發(fa)出停機(ji)(ji)指令。 4.其它各種技術(shu) 近年來，國內外一些(xie)公司都(dou)在研制(zhi)(zhi)新型“無(wu)電(dian)(dian)(dian)網(wang)污染”的(de)(de)高(gao)壓變(bian)(bian)(bian)(bian)頻(pin)器。據報道，這(zhe)類(lei)變(bian)(bian)(bian)(bian)頻(pin)裝(zhuang)置具有(you)高(gao)功率(lv)因(yin)數、高(gao)效率(lv)、無(wu)諧波污染、無(wu)需專(zhuan)用電(dian)(dian)(dian)機等(deng)優點，采用了(le)多項先進技術：(1)在變(bian)(bian)(bian)(bian)頻(pin)器的(de)(de)逆變(bian)(bian)(bian)(bian)器直流側(ce)通過曲折變(bian)(bian)(bian)(bian)壓器移相實現30“脈波整流，使裝(zhuang)置的(de)(de)諧波抑制(zhi)(zhi)能(neng)力大大加強，使電(dian)(dian)(dian)網(wang)側(ce)電(dian)(dian)(dian)壓與電(dian)(dian)(dian)流之間幾(ji)乎無(wu)相移，因(yin)此功率(lv)因(yin)數可(ke)以(yi)接近于(yu)1。；(2)將全(quan)數字化(hua)光纖控制(zhi)(zhi)技術應用于(yu)變(bian)(bian)(bian)(bian)頻(pin)器，使其(qi)控制(zhi)(zhi)柔性(xing)和(he)可(ke)靠(kao)性(xing)大大提高(gao)。(3)功率(lv)單(dan)元(yuan)標準(zhun)模塊化(hua)、IGBT驅動電(dian)(dian)(dian)路智能(neng)化(hua)。
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