一、串聯電抗器和并聯電抗器的區別在哪里
串(chuan)聯電抗(kang)器(qi)與(yu)并(bing)聯電抗(kang)器(qi)有明顯區別,體(ti)現在作(zuo)(zuo)(zuo)用和適用范圍(wei)上,串(chuan)聯電抗(kang)器(qi)主要(yao)起限(xian)流和濾波(bo)作(zuo)(zuo)(zuo)用,并(bing)聯電抗(kang)器(qi)主要(yao)起無功(gong)補(bu)償作(zuo)(zuo)(zuo)用,下面做詳細介紹:
1、串聯電(dian)(dian)(dian)(dian)抗器(qi)(qi)是電(dian)(dian)(dian)(dian)力(li)系統無功(gong)補償裝置(zhi)的重要配(pei)套設備。電(dian)(dian)(dian)(dian)力(li)電(dian)(dian)(dian)(dian)容器(qi)(qi)與串聯電(dian)(dian)(dian)(dian)抗器(qi)(qi)串聯后,能有效(xiao)地抑(yi)制(zhi)電(dian)(dian)(dian)(dian)網中的高次(ci)諧波(bo),限制(zhi)合閘涌流及(ji)操作過(guo)電(dian)(dian)(dian)(dian)壓,改(gai)善系統的電(dian)(dian)(dian)(dian)壓波(bo)形,提高電(dian)(dian)(dian)(dian)網功(gong)率因(yin)數,對電(dian)(dian)(dian)(dian)力(li)電(dian)(dian)(dian)(dian)容器(qi)(qi)及(ji)其它電(dian)(dian)(dian)(dian)力(li)設備的安全(quan)運行起到了較大(da)的作用。
串聯電抗器主要用于限(xian)制短路電(dian)流(liu),而電(dian)容器(qi)組串聯(lian)電(dian)抗器(qi)可以限(xian)制高(gao)次諧(xie)波,降低(di)電(dian)抗。
2、并聯電抗器(qi)可以用(yong)于(yu)補償(chang)長距離輸(shu)電線路的分布(bu)電容補償(chang),防(fang)止(zhi)空載長線路末(mo)端(duan)電壓(ya)升高(通(tong)常用(yong)于(yu)500KV系統),還(huan)可以有利(li)于(yu)單相(xiang)重合(he)閘(zha)和降低(di)操(cao)作(zuo)過電壓(ya)。
為了提(ti)高遠(yuan)距離(li)輸電(dian)(dian)線(xian)路(lu)的(de)(de)傳輸能力和(he)(he)改善(shan)線(xian)路(lu)的(de)(de)運行情(qing)況(kuang),削弱空載(zai)或(huo)輕(qing)載(zai)時(shi)長線(xian)路(lu)的(de)(de)電(dian)(dian)容效(xiao)應所引起的(de)(de)工頻電(dian)(dian)壓升(sheng)高,改善(shan)沿線(xian)電(dian)(dian)壓分布和(he)(he)輕(qing)載(zai)線(xian)路(lu)中的(de)(de)無功分布并(bing)降低線(xian)損,減少潛(qian)供電(dian)(dian)流,加(jia)速潛(qian)供電(dian)(dian)弧的(de)(de)熄滅,提(ti)高線(xian)路(lu)自動(dong)重合閘(zha)的(de)(de)成(cheng)功率,并(bing)聯電(dian)(dian)抗器被廣泛應用于(yu)電(dian)(dian)網的(de)(de)遠(yuan)距離(li)輸配電(dian)(dian)項目。
二、串聯電抗器的電流大嗎
確定電(dian)(dian)容器(qi)串聯電(dian)(dian)抗(kang)器(qi)回路的(de)電(dian)(dian)流,應該把電(dian)(dian)容器(qi)和串聯電(dian)(dian)抗(kang)器(qi)作為一個回路整體(ti)來分析(xi),因為補償回路中除(chu)了要(yao)承(cheng)載正常的(de)基波無功電(dian)(dian)流外(wai),還應該允許它能(neng)夠承(cheng)載一定量(liang)的(de)某次諧波電(dian)(dian)流。
串聯電抗器的電(dian)容(rong)器補(bu)(bu)償回(hui)路(lu),常情況下(xia)補(bu)(bu)償容(rong)量(liang)及(ji)通(tong)過(guo)的電(dian)流如何計算呢,現舉例如下(xia):如果回(hui)路(lu)電(dian)抗器的電(dian)抗率為(wei)14%,系統電(dian)壓為(wei)400V。
電(dian)容(rong)(rong)器承受(shou)的(de)(de)(de)電(dian)壓(ya)為(wei)(wei):400(1-14%)=465.1V,如果選(xuan)擇所配(pei)套的(de)(de)(de)電(dian)容(rong)(rong)器額(e)定(ding)電(dian)壓(ya)為(wei)(wei)525V(也可以為(wei)(wei)480V),額(e)定(ding)電(dian)壓(ya)525V,容(rong)(rong)量(liang)為(wei)(wei)30Kvar的(de)(de)(de)電(dian)容(rong)(rong)器額(e)定(ding)電(dian)流(liu)(liu)為(wei)(wei)33A,串聯電(dian)抗率14%的(de)(de)(de)后實(shi)際發出30x(465.1/525)2-23.5Kvar,向(xiang)電(dian)網只能補(bu)償23.5x(1-14%)=20.1Kvar的(de)(de)(de)無功功率,此時通過(guo)電(dian)容(rong)(rong)器的(de)(de)(de)電(dian)流(liu)(liu)23.5/(V3x0.4651)=29.2(A)。此時通過(guo)的(de)(de)(de)電(dian)流(liu)(liu)遠小于額(e)定(ding)電(dian)流(liu)(liu)33A了。
所以(yi)串聯電抗器的電流是不(bu)大的。