一、什么是風電變流器
風(feng)電(dian)變流(liu)器,是(shi)雙(shuang)饋風(feng)力發電(dian)機(ji)中(zhong),加在轉子(zi)側(ce)的勵(li)磁裝(zhuang)置,其主要(yao)功能是(shi)在轉子(zi)轉速(su)n變化時,通過變流(liu)器控制勵(li)磁的幅值、相位、頻(pin)率等(deng),使定(ding)子(zi)側(ce)能向電(dian)網輸入恒頻(pin)電(dian)。
二、風電變流器的結構組成
風電(dian)(dian)變(bian)(bian)流器(qi)可以優化風力發(fa)電(dian)(dian)系(xi)統的(de)運行,實現寬風速范圍內的(de)變(bian)(bian)速恒(heng)頻發(fa)電(dian)(dian),改善(shan)風機效(xiao)率(lv)(lv)和傳輸鏈的(de)工作狀況,減少(shao)發(fa)電(dian)(dian)機損耗,提(ti)高運行效(xiao)率(lv)(lv),提(ti)升風能利用率(lv)(lv),在(zai)風電(dian)(dian)領域(yu)應(ying)用廣泛(fan),那么風電(dian)(dian)變(bian)(bian)流器(qi)的(de)結(jie)構由哪些部分組成呢?
風電變流(liu)器由主電路系統(tong)、配電系統(tong)以(yi)及控制系統(tong)構成,其(qi)零部件主要(yao)有定子并網開關、整流(liu)模(mo)塊(kuai)、逆變模(mo)塊(kuai)、輸入/輸出濾波器、IGBT、PLC、JCE1000-AXS電流(liu)傳感器、風機、有源Crowbar電路、控制器、監控界(jie)面等。
1、變(bian)流器(qi)主電(dian)路系統包括轉子(zi)側(ce)逆(ni)變(bian)器(qi)、直流母線單元(yuan)、電(dian)網(wang)側(ce)整流器(qi)。
2、配電系統由并(bing)網接(jie)觸器(qi)、主斷路(lu)器(qi)、繼電器(qi)、變壓器(qi)等組成,自(zi)身集(ji)成有并(bing)網控制系統。
3、控(kong)制(zhi)系統由高速數(shu)字信號處理器(DSP)、人機操(cao)作界面和可編程(cheng)邏(luo)輯控(kong)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)(dian)(dian)變流器采用三相(xiang)電(dian)(dian)(dian)壓型交-直-交雙向變流器技(ji)術,通過對雙饋異步風力發電(dian)(dian)(dian)機的(de)(de)轉子進(jin)行勵磁,使得(de)雙饋發電(dian)(dian)(dian)機的(de)(de)定子側(ce)輸出電(dian)(dian)(dian)壓的(de)(de)幅值、頻率和(he)相(xiang)位與電(dian)(dian)(dian)網相(xiang)同,并且可(ke)根據(ju)需要進(jin)行有(you)功和(he)無功的(de)(de)獨立解耦控制,具體(ti)的(de)(de)工作原理是:
在直(zhi)驅型風力發電(dian)系(xi)統中,全功率變(bian)(bian)(bian)(bian)流(liu)(liu)(liu)(liu)(liu)器(qi)(qi)是永(yong)磁同步(bu)發電(dian)機與電(dian)網之間(jian)的(de)(de)橋梁。永(yong)磁同步(bu)發電(dian)機發出的(de)(de)交(jiao)流(liu)(liu)(liu)(liu)(liu)電(dian)是隨著風的(de)(de)變(bian)(bian)(bian)(bian)化(hua)(hua)而變(bian)(bian)(bian)(bian)化(hua)(hua)的(de)(de),不能(neng)直(zhi)接接入電(dian)網。變(bian)(bian)(bian)(bian)流(liu)(liu)(liu)(liu)(liu)器(qi)(qi)的(de)(de)機側對(dui)幅(fu)值(zhi)和(he)頻率變(bian)(bian)(bian)(bian)化(hua)(hua)的(de)(de)交(jiao)流(liu)(liu)(liu)(liu)(liu)進行PWM整(zheng)流(liu)(liu)(liu)(liu)(liu),整(zheng)流(liu)(liu)(liu)(liu)(liu)后的(de)(de)直(zhi)流(liu)(liu)(liu)(liu)(liu)經變(bian)(bian)(bian)(bian)流(liu)(liu)(liu)(liu)(liu)器(qi)(qi)的(de)(de)網側進行PWM逆變(bian)(bian)(bian)(bian),將直(zhi)流(liu)(liu)(liu)(liu)(liu)逆變(bian)(bian)(bian)(bian)成幅(fu)值(zhi)和(he)頻率穩(wen)定的(de)(de)交(jiao)流(liu)(liu)(liu)(liu)(liu),經濾(lv)波器(qi)(qi)、升壓(ya)變(bian)(bian)(bian)(bian)壓(ya)器(qi)(qi)并入電(dian)網。
風電變流器的機側(ce)接入(ru)永(yong)磁發電機的兩(liang)個(ge)(ge)(ge)繞組(zu),根據主控(kong)(kong)系統(tong)(tong)(tong)轉(zhuan)矩指令(ling),機側(ce)1#繞組(zu)控(kong)(kong)制(zhi)系統(tong)(tong)(tong)控(kong)(kong)制(zhi)1#橋(qiao)單元(yuan),機側(ce)2#繞組(zu)控(kong)(kong)制(zhi)系統(tong)(tong)(tong)控(kong)(kong)制(zhi)2#橋(qiao)單元(yuan),進(jin)(jin)行(xing)(xing)PWM整流,從而實現變(bian)(bian)(bian)流器(qi)(qi)對永(yong)磁同(tong)步(bu)發電機的控(kong)(kong)制(zhi)。變(bian)(bian)(bian)流器(qi)(qi)的網(wang)(wang)側(ce)輸出接到升(sheng)壓(ya)變(bian)(bian)(bian)壓(ya)器(qi)(qi)并網(wang)(wang),根據直(zhi)流電壓(ya)和(he)(he)主控(kong)(kong)下設(she)(she)無功(gong)功(gong)率(lv),網(wang)(wang)側(ce)控(kong)(kong)制(zhi)系統(tong)(tong)(tong)采用(yong)矢量控(kong)(kong)制(zhi)技術控(kong)(kong)制(zhi)三(san)(san)個(ge)(ge)(ge)相單元(yuan),將(jiang)有功(gong)和(he)(he)設(she)(she)定的無功(gong)經濾波器(qi)(qi)送入(ru)電網(wang)(wang)。如果單獨運行(xing)(xing)網(wang)(wang)側(ce)逆變(bian)(bian)(bian)單元(yuan),可以作為靜態無功(gong)發生(sheng)器(qi)(qi)(SVG)使用(yong),對電網(wang)(wang)進(jin)(jin)行(xing)(xing)無功(gong)補償(chang)。控(kong)(kong)制(zhi)系統(tong)(tong)(tong)采用(yong)三(san)(san)個(ge)(ge)(ge)DSP分別對變(bian)(bian)(bian)流器(qi)(qi)的電機側(ce)1#繞組(zu)、電機側(ce)2#繞組(zu)和(he)(he)電網(wang)(wang)側(ce)進(jin)(jin)行(xing)(xing)控(kong)(kong)制(zhi),在三(san)(san)個(ge)(ge)(ge)DSP之間(jian)采用(yong)高(gao)速(su)串行(xing)(xing)總線(xian)進(jin)(jin)行(xing)(xing)通(tong)訊(xun)以協(xie)調機側(ce)和(he)(he)網(wang)(wang)側(ce)之間(jian)的工作。