隨著國民經濟的發展，電力負荷的增加必然需要電網系統利用率的提高。但由于絕大多數接入電網的電氣設備都是電感負荷，自然功率因素較低，影響發電機的輸出功率；降低有功功率輸出；影響變電站。輸電的供電能力；降低有功功率容量；增加電力系統的電能損耗；增加輸電線路的電壓降。因此，連接到電網中的大多數電器不僅需要有功功率，還需要一定的無功功率。

目(mu)前(qian)，在(zai)110kV及(ji)以下的電(dian)(dian)網中，經常安裝電(dian)(dian)力電(dian)(dian)容器組(zu)進行無功功率(lv)補(bu)償，這(zhe)是(shi)一種實用、經濟的方法。

無(wu)功(gong)(gong)補(bu)償(chang)可降(jiang)低(di)設(she)計容量；減少投資(zi)；提高電(dian)(dian)網(wang)功(gong)(gong)率(lv)輸送比例(li)，降(jiang)低(di)線路(lu)損耗(hao)，提高電(dian)(dian)壓質量，穩定設(she)備(bei)(bei)運(yun)行(xing)；提高低(di)壓電(dian)(dian)網(wang)和(he)電(dian)(dian)氣設(she)備(bei)(bei)功(gong)(gong)率(lv)因素，降(jiang)低(di)功(gong)(gong)率(lv)損耗(hao)和(he)節能；降(jiang)低(di)用戶電(dian)(dian)費；滿足電(dian)(dian)力系統無(wu)功(gong)(gong)補(bu)償(chang)的(de)檢測要求，消除低(di)功(gong)(gong)率(lv)因素造(zao)成的(de)罰(fa)款。

安全運行五點：

1.允許運行電流

正(zheng)常運(yun)行時，電(dian)容(rong)器應在額(e)定電(dian)流下運(yun)行，最大運(yun)行電(dian)流不得超過(guo)(guo)額(e)定電(dian)流的1.3倍，三相電(dian)流差不得超過(guo)(guo)5%。

2.允許運行電壓

電(dian)(dian)容器對電(dian)(dian)壓(ya)非常(chang)敏感，因(yin)為電(dian)(dian)容器的(de)損耗與電(dian)(dian)壓(ya)平方(fang)成正比，過電(dian)(dian)壓(ya)會(hui)嚴重加熱電(dian)(dian)容器，電(dian)(dian)容器絕緣會(hui)加速老化，縮短壽命(ming)，甚至電(dian)(dian)擊(ji)穿。

因此，電(dian)容器裝置應在額定電(dian)壓(ya)(ya)下運行，一(yi)般不得超過(guo)額定電(dian)壓(ya)(ya)的(de)1.05倍(bei)，最大運行電(dian)壓(ya)(ya)不得超過(guo)額定電(dian)壓(ya)(ya)的(de)1.1倍(bei)。當母線超過(guo)額定電(dian)壓(ya)(ya)的(de)1.1倍(bei)時(shi)，應采取(qu)冷(leng)卻措施。

3.諧波問題

由于電(dian)(dian)(dian)容(rong)(rong)器(qi)電(dian)(dian)(dian)路(lu)是液晶電(dian)(dian)(dian)路(lu)，因(yin)(yin)此(ci)容(rong)(rong)易對(dui)某些(xie)諧(xie)波產生諧(xie)振，容(rong)(rong)易引(yin)起(qi)高(gao)諧(xie)波，增加(jia)電(dian)(dian)(dian)流(liu)和電(dian)(dian)(dian)壓。諧(xie)波電(dian)(dian)(dian)流(liu)對(dui)電(dian)(dian)(dian)容(rong)(rong)器(qi)非常有害，很容(rong)(rong)易使電(dian)(dian)(dian)容(rong)(rong)器(qi)突破，導致相間(jian)短路(lu)。因(yin)(yin)此(ci)，當(dang)電(dian)(dian)(dian)容(rong)(rong)器(qi)正常工作時，必要(yao)時可(ke)以(yi)在(zai)電(dian)(dian)(dian)容(rong)(rong)器(qi)上串聯適(shi)當(dang)的電(dian)(dian)(dian)抗器(qi)，以(yi)限制諧(xie)波電(dian)(dian)(dian)流(liu)。

4.繼電保護問題

繼電(dian)保(bao)(bao)護(hu)主要由成(cheng)(cheng)套繼電(dian)保(bao)(bao)護(hu)裝(zhuang)置實(shi)現。目前，國內幾家(jia)知名電(dian)氣(qi)廠家(jia)生產的繼電(dian)保(bao)(bao)護(hu)裝(zhuang)置技術非常成(cheng)(cheng)熟，安全穩定，功能強(qiang)大。繼電(dian)保(bao)(bao)護(hu)裝(zhuang)置能有效去除(chu)故障電(dian)容器，是保(bao)(bao)證電(dian)力系統安全穩定運(yun)行的重要手(shou)段(duan)。

電容(rong)器(qi)的(de)主要(yao)繼電保護(hu)措施有：①三段過(guo)(guo)流保護(hu)；②為防止(zhi)系統穩態過(guo)(guo)壓(ya)(ya)造成(cheng)(cheng)電容(rong)器(qi)損壞而設(she)(she)置的(de)過(guo)(guo)電壓(ya)(ya)保護(hu)；③為避免系統電源短暫停(ting)機造成(cheng)(cheng)電容(rong)器(qi)瞬時重(zhong)疊造成(cheng)(cheng)的(de)過(guo)(guo)電壓(ya)(ya)損壞而設(she)(she)置的(de)低電壓(ya)(ya)保護(hu)；④不平衡電壓(ya)(ya)保護(hu)、不平衡電流保護(hu)或三相差電壓(ya)(ya)保護(hu)。

5.合閘問題

禁止(zhi)帶電(dian)(dian)重合閘電(dian)(dian)容(rong)器(qi)組(zu)。主要(yao)原因是電(dian)(dian)容(rong)器(qi)放電(dian)(dian)需要(yao)一定的(de)時(shi)間。當電(dian)(dian)容(rong)器(qi)組(zu)開關(guan)跳閘時(shi)，如果(guo)電(dian)(dian)容(rong)器(qi)立即(ji)重合閘，放電(dian)(dian)太晚(wan)，與重合閘電(dian)(dian)壓極性相反的(de)電(dian)(dian)荷可能會(hui)殘留(liu)在電(dian)(dian)容(rong)器(qi)中，這會(hui)在關(guan)閉時(shi)產(chan)生很大的(de)沖擊(ji)電(dian)(dian)流，導致(zhi)電(dian)(dian)容(rong)器(qi)外殼(ke)膨脹、噴(pen)油甚至爆炸。

因此，當(dang)電容(rong)器組再(zai)次合(he)閘(zha)時，斷(duan)路器必須斷(duan)開3分鐘。因此，電容(rong)器不允許安裝自動重合(he)閘(zha)裝置(zhi)，相反，應安裝無壓釋放自動跳閘(zha)裝置(zhi)。