電容補償柜在電網中的作用

電(dian)(dian)力(li)系統中的負載類型大(da)(da)部分屬于感性負載，加(jia)上用(yong)電(dian)(dian)企業普遍廣泛地使用(yong)電(dian)(dian)力(li)電(dian)(dian)子設備(bei)(bei)，使電(dian)(dian)網(wang)功(gong)率因數(shu)較低(di)。較低(di)的功(gong)率因數(shu)降低(di)了(le)(le)設備(bei)(bei)利(li)用(yong)率，增(zeng)加(jia)了(le)(le)供電(dian)(dian)投資，損(sun)害了(le)(le)電(dian)(dian)壓質量，降低(di)了(le)(le)設備(bei)(bei)使用(yong)壽命(ming)，大(da)(da)大(da)(da)增(zeng)加(jia)了(le)(le)線路損(sun)耗(hao)。

電(dian)(dian)容補償柜的(de)基本原理(li)：在實際(ji)電(dian)(dian)力系統(tong)中(zhong)，大部(bu)分的(de)負載為異步電(dian)(dian)動(dong)機。其等效電(dian)(dian)路可看做電(dian)(dian)阻和電(dian)(dian)感的(de)串聯電(dian)(dian)路，其電(dian)(dian)壓和電(dian)(dian)流的(de)相位差(cha)較大，功(gong)率(lv)因(yin)數(shu)較低，并聯電(dian)(dian)容器(qi)(qi)后，電(dian)(dian)容器(qi)(qi)的(de)電(dian)(dian)流將抵消一部(bu)分電(dian)(dian)感電(dian)(dian)流，從而(er)使電(dian)(dian)感電(dian)(dian)流減小，總電(dian)(dian)流隨之減小，電(dian)(dian)壓和電(dian)(dian)流的(de)相位差(cha)變小，使功(gong)率(lv)因(yin)數(shu)提高(gao)。

一(yi)般來說，低(di)壓電(dian)容(rong)補(bu)償(chang)柜由柜體、母排、熔(rong)斷器、隔(ge)離開關熔(rong)斷器組(zu)、電(dian)容(rong)接觸器、避雷器、電(dian)容(rong)器、電(dian)抗器、一(yi)、二次導線、端子排、功率因(yin)數(shu)自(zi)動補(bu)償(chang)控制裝置、盤面儀表等組(zu)成。低(di)壓電(dian)容(rong)補(bu)償(chang)柜是在變壓器的(de)(de)(de)低(di)壓側運(yun)行(xing)的(de)(de)(de)，一(yi)般它(ta)受功率因(yin)素(su)控制而(er)自(zi)動運(yun)行(xing)的(de)(de)(de)。因(yin)所帶負載的(de)(de)(de)種(zhong)類不同而(er)確(que)定電(dian)容(rong)的(de)(de)(de)容(rong)量(liang)(liang)及電(dian)容(rong)組(zu)的(de)(de)(de)數(shu)量(liang)(liang)，當供用電(dian)系統正(zheng)常時(shi)，由控制器捕捉功率因(yin)素(su)來控制投入的(de)(de)(de)電(dian)容(rong)組(zu)的(de)(de)(de)數(shu)量(liang)(liang)。

電(dian)(dian)(dian)(dian)容(rong)(rong)補償柜在原(yuan)理上相當于產生(sheng)容(rong)(rong)性(xing)無功(gong)電(dian)(dian)(dian)(dian)流的(de)發動機，其補償原(yuan)理是把具有容(rong)(rong)性(xing)功(gong)率(lv)負荷的(de)裝置和感性(xing)功(gong)率(lv)負荷并聯在同(tong)一(yi)電(dian)(dian)(dian)(dian)容(rong)(rong)器上，能量在兩種負荷間相互(hu)轉(zhuan)換(huan)。這樣(yang)，電(dian)(dian)(dian)(dian)網中的(de)變壓器和輸電(dian)(dian)(dian)(dian)線路的(de)負荷降低(di)，從而輸出(chu)的(de)有功(gong)能力增加，在輸出(chu)一(yi)定(ding)有功(gong)功(gong)率(lv)的(de)情況下，供電(dian)(dian)(dian)(dian)系(xi)統(tong)的(de)損(sun)耗(hao)降低(di)。比(bi)較起來電(dian)(dian)(dian)(dian)容(rong)(rong)器是減輕變壓器、供電(dian)(dian)(dian)(dian)系(xi)統(tong)配電(dian)(dian)(dian)(dian)負荷的(de)簡(jian)單、經濟的(de)方法。