一、什么是風電變流器
風電(dian)(dian)(dian)變(bian)流(liu)器,是(shi)雙饋風力發電(dian)(dian)(dian)機(ji)中,加在轉(zhuan)子(zi)(zi)側的勵磁裝置,其主要功能(neng)是(shi)在轉(zhuan)子(zi)(zi)轉(zhuan)速n變(bian)化時,通過(guo)變(bian)流(liu)器控制(zhi)勵磁的幅值(zhi)、相(xiang)位、頻率(lv)等,使定子(zi)(zi)側能(neng)向(xiang)電(dian)(dian)(dian)網輸入(ru)恒頻電(dian)(dian)(dian)。
二、風電變流器的結構組成
風(feng)電(dian)(dian)變(bian)流器可以(yi)優化風(feng)力(li)發電(dian)(dian)系(xi)統的運行,實現寬風(feng)速范圍(wei)內的變(bian)速恒(heng)頻發電(dian)(dian),改善風(feng)機效率(lv)和(he)傳輸鏈的工作(zuo)狀況(kuang),減少發電(dian)(dian)機損(sun)耗,提高運行效率(lv),提升(sheng)風(feng)能利用率(lv),在(zai)風(feng)電(dian)(dian)領域應用廣泛,那么風(feng)電(dian)(dian)變(bian)流器的結構由哪些部分組(zu)成呢?
風(feng)電(dian)變(bian)流器由(you)主(zhu)電(dian)路系統(tong)、配電(dian)系統(tong)以及控制系統(tong)構成,其零部件主(zhu)要有定子并(bing)網(wang)開關、整流模(mo)(mo)塊(kuai)、逆變(bian)模(mo)(mo)塊(kuai)、輸入/輸出(chu)濾波器、IGBT、PLC、JCE1000-AXS電(dian)流傳感器、風(feng)機(ji)、有源(yuan)Crowbar電(dian)路、控制器、監控界(jie)面等。
1、變流器(qi)(qi)主電路系統包括轉(zhuan)子側逆變器(qi)(qi)、直流母線單元、電網(wang)側整流器(qi)(qi)。
2、配電系(xi)統由并(bing)網接觸器(qi)、主斷(duan)路器(qi)、繼電器(qi)、變壓(ya)器(qi)等組成,自身集成有并(bing)網控制系(xi)統。
3、控制(zhi)系(xi)統由(you)高速數(shu)字信號處理(li)器(DSP)、人(ren)機操(cao)作界面(mian)和可編(bian)程邏(luo)輯控制(zhi)器(PLC)共同構(gou)成。
三、風電變流器工作原理是什么
風電(dian)變(bian)流器采用三相電(dian)壓(ya)型交-直-交雙向變(bian)流器技(ji)術,通過對雙饋(kui)異(yi)步風力發(fa)電(dian)機(ji)的轉(zhuan)子(zi)進行勵(li)磁,使(shi)得雙饋(kui)發(fa)電(dian)機(ji)的定子(zi)側輸出電(dian)壓(ya)的幅值、頻率和(he)相位與電(dian)網相同,并且可(ke)根據需(xu)要進行有功和(he)無功的獨立(li)解耦(ou)控制,具(ju)體的工作原理是:
在直(zhi)(zhi)(zhi)驅型(xing)風(feng)力(li)發電(dian)系(xi)統中,全(quan)功率變(bian)(bian)流(liu)器(qi)(qi)是(shi)永磁同(tong)步發電(dian)機(ji)與電(dian)網(wang)之(zhi)間的(de)(de)(de)橋梁。永磁同(tong)步發電(dian)機(ji)發出的(de)(de)(de)交(jiao)流(liu)電(dian)是(shi)隨著(zhu)風(feng)的(de)(de)(de)變(bian)(bian)化而變(bian)(bian)化的(de)(de)(de),不能直(zhi)(zhi)(zhi)接接入電(dian)網(wang)。變(bian)(bian)流(liu)器(qi)(qi)的(de)(de)(de)機(ji)側(ce)對幅值和頻(pin)率變(bian)(bian)化的(de)(de)(de)交(jiao)流(liu)進(jin)(jin)行(xing)PWM整(zheng)流(liu),整(zheng)流(liu)后的(de)(de)(de)直(zhi)(zhi)(zhi)流(liu)經變(bian)(bian)流(liu)器(qi)(qi)的(de)(de)(de)網(wang)側(ce)進(jin)(jin)行(xing)PWM逆(ni)(ni)變(bian)(bian),將直(zhi)(zhi)(zhi)流(liu)逆(ni)(ni)變(bian)(bian)成幅值和頻(pin)率穩定的(de)(de)(de)交(jiao)流(liu),經濾波器(qi)(qi)、升壓(ya)(ya)變(bian)(bian)壓(ya)(ya)器(qi)(qi)并(bing)入電(dian)網(wang)。
風電變流器的(de)機(ji)側(ce)(ce)接(jie)入永(yong)磁(ci)發電(dian)(dian)機(ji)的(de)兩個(ge)繞(rao)組(zu),根據主控(kong)系統(tong)轉(zhuan)矩指令,機(ji)側(ce)(ce)1#繞(rao)組(zu)控(kong)制(zhi)(zhi)(zhi)(zhi)系統(tong)控(kong)制(zhi)(zhi)(zhi)(zhi)1#橋單元(yuan),機(ji)側(ce)(ce)2#繞(rao)組(zu)控(kong)制(zhi)(zhi)(zhi)(zhi)系統(tong)控(kong)制(zhi)(zhi)(zhi)(zhi)2#橋單元(yuan),進行(xing)(xing)(xing)PWM整流(liu),從而實現變(bian)流(liu)器(qi)對(dui)永(yong)磁(ci)同步(bu)發電(dian)(dian)機(ji)的(de)控(kong)制(zhi)(zhi)(zhi)(zhi)。變(bian)流(liu)器(qi)的(de)網側(ce)(ce)輸出(chu)接(jie)到升(sheng)壓(ya)變(bian)壓(ya)器(qi)并網,根據直(zhi)流(liu)電(dian)(dian)壓(ya)和主控(kong)下設(she)無(wu)功(gong)(gong)功(gong)(gong)率,網側(ce)(ce)控(kong)制(zhi)(zhi)(zhi)(zhi)系統(tong)采用(yong)(yong)矢(shi)量控(kong)制(zhi)(zhi)(zhi)(zhi)技術控(kong)制(zhi)(zhi)(zhi)(zhi)三(san)個(ge)相單元(yuan),將有功(gong)(gong)和設(she)定的(de)無(wu)功(gong)(gong)經濾波器(qi)送入電(dian)(dian)網。如(ru)果單獨運行(xing)(xing)(xing)網側(ce)(ce)逆(ni)變(bian)單元(yuan),可(ke)以作(zuo)(zuo)為(wei)靜態無(wu)功(gong)(gong)發生器(qi)(SVG)使(shi)用(yong)(yong),對(dui)電(dian)(dian)網進行(xing)(xing)(xing)無(wu)功(gong)(gong)補償。控(kong)制(zhi)(zhi)(zhi)(zhi)系統(tong)采用(yong)(yong)三(san)個(ge)DSP分(fen)別對(dui)變(bian)流(liu)器(qi)的(de)電(dian)(dian)機(ji)側(ce)(ce)1#繞(rao)組(zu)、電(dian)(dian)機(ji)側(ce)(ce)2#繞(rao)組(zu)和電(dian)(dian)網側(ce)(ce)進行(xing)(xing)(xing)控(kong)制(zhi)(zhi)(zhi)(zhi),在(zai)三(san)個(ge)DSP之(zhi)間(jian)采用(yong)(yong)高速串行(xing)(xing)(xing)總線進行(xing)(xing)(xing)通訊以協調機(ji)側(ce)(ce)和網側(ce)(ce)之(zhi)間(jian)的(de)工作(zuo)(zuo)。