蘭州(zhou)箱式(shi)變電(dian)站中(zhong)電(dian)抗器的作用是什(shen)么？

國家電(dian)(dian)(dian)網的(de)電(dian)(dian)(dian)力(li)(li)系(xi)統(tong)中所(suo)采用的(de)電(dian)(dian)(dian)抗(kang)器，實質上只是一(yi)個無導磁材料(liao)的(de)空心線圈(quan)，他可(ke)(ke)以根(gen)據布置需要(yao)(yao)裝配成(cheng)垂(chui)直、水平和(he)品(pin)字形(xing)三種形(xing)式。在(zai)電(dian)(dian)(dian)力(li)(li)生產(chan)輸(shu)送運行中，當電(dian)(dian)(dian)力(li)(li)系(xi)統(tong)發生短路(lu)時(shi)，會(hui)產(chan)生數值很大(da)的(de)短路(lu)電(dian)(dian)(dian)流，如果不加(jia)以控制(zhi)，就會(hui)導致電(dian)(dian)(dian)力(li)(li)系(xi)統(tong)中的(de)電(dian)(dian)(dian)氣(qi)設備損壞，嚴重的(de)可(ke)(ke)能(neng)照(zhao)成(cheng)事故(gu)。因此，即使電(dian)(dian)(dian)力(li)(li)系(xi)統(tong)發生短路(lu)也(ye)要(yao)(yao)設法保(bao)持電(dian)(dian)(dian)氣(qi)設備的(de)動(dong)態穩定和(he)熱穩定性(xing)。所(suo)以電(dian)(dian)(dian)力(li)(li)部門常在(zai)出(chu)線斷路(lu)器處安裝串聯電(dian)(dian)(dian)抗(kang)器，來增大(da)短路(lu)阻抗(kang)，限制(zhi)短路(lu)電(dian)(dian)(dian)流，以滿(man)足各種斷路(lu)器遮(zhe)斷容量的(de)要(yao)(yao)求。

甘(gan)肅(su)箱式變(bian)電站使(shi)用電抗器后，在發生短路(lu)時，電抗器的電壓降較大(da)，使(shi)母(mu)線上的電壓波(bo)動(dong)較小，起到了(le)維(wei)持母(mu)線電壓水平的作用，保證了(le)非(fei)故障線路(lu)上的用戶(hu)電氣設備(bei)運行穩定。

箱式(shi)變電(dian)(dian)站的高壓電(dian)(dian)抗器(qi)可分為串聯(lian)電(dian)(dian)抗器(qi)、并聯(lian)電(dian)(dian)抗器(qi)。

箱式變電站內并聯電抗器的作用:

1、削弱箱(xiang)式變電站內空載或(huo)輕(qing)載時(shi)長線(xian)路的電容(rong)效應(ying)所引起的工頻電壓升(sheng)高：

這種電壓升高(gao)是由于(yu)空載或輕載時(shi)，線路的電容(rong)(對(dui)低電容和相間電容)電(dian)流在(zai)線(xian)路的(de)電(dian)感(gan)上的(de)壓降所引起的(de)。它(ta)將使線(xian)路電(dian)壓高于(yu)電(dian)源電(dian)壓。當愈嚴重(zhong)，通(tong)常線(xian)路愈長，則(ze)電(dian)容(rong)效應愈大，工頻(pin)電(dian)壓升高也愈大。

對超高壓(ya)遠距離(li)輸電(dian)(dian)線路(lu)(lu)而言(yan)，空載(zai)或(huo)輕載(zai)時(shi)線路(lu)(lu)電(dian)(dian)容的充電(dian)(dian)功(gong)(gong)率(lv)是很大(da)的，通(tong)常充電(dian)(dian)功(gong)(gong)率(lv)隨電(dian)(dian)壓(ya)的平方(fang)面(mian)急劇(ju)增加，巨大(da)的充電(dian)(dian)功(gong)(gong)率(lv)除引起上述工頻電(dian)(dian)壓(ya)升高現象之(zhi)外(wai)，還將(jiang)增大(da)線路(lu)(lu)的功(gong)(gong)率(lv)和電(dian)(dian)能損耗(hao)以及引起自勵磁，同期困難等問題。裝設并聯電(dian)(dian)抗器可(ke)以補償這部分充電(dian)(dian)功(gong)(gong)率(lv)；

2、改善箱式變電(dian)(dian)站沿(yan)線電(dian)(dian)壓分布和輕載線路(lu)中的無功分布并降(jiang)低(di)線損：

當(dang)線(xian)(xian)路上(shang)傳輸(shu)的(de)功率(lv)不等(deng)于自(zi)然功率(lv)時(shi)，則沿線(xian)(xian)各點電(dian)壓(ya)將偏離(li)額定(ding)值(zhi)，有時(shi)甚至偏離(li)較大，如依靠并聯電(dian)抗器的(de)補償(chang)，則可以仰低線(xian)(xian)路電(dian)壓(ya)得升高；

3、減少箱式變電站(zhan)內潛(qian)供電流，加速潛(qian)供電弧的熄滅，提高(gao)線(xian)路自(zi)動重合閘的成功率(lv)：

所謂(wei)潛供(gong)電(dian)(dian)流，是指當發生單相(xiang)瞬(shun)時接(jie)地故障(zhang)(zhang)時，在故障(zhang)(zhang)相(xiang)兩側斷開(kai)后，故障(zhang)(zhang)點處弧(hu)光(guang)中(zhong)所存在的(de)殘余(yu)電(dian)(dian)流。并聯(lian)電(dian)(dian)抗器的(de)中(zhong)性點經小抗接(jie)地的(de)方法來補償潛供(gong)電(dian)(dian)流，從而加快潛供(gong)電(dian)(dian)弧(hu)的(de)熄滅；

4、并(bing)聯電(dian)(dian)抗(kang)器并(bing)聯在主變(bian)的(de)低壓側(ce)母線(xian)上，通過主變(bian)向系統(tong)輸送(song)感性無功，用以補償輸電(dian)(dian)線(xian)路(lu)的(de)電(dian)(dian)容電(dian)(dian)流，防止輕(qing)負荷(he)線(xian)端(duan)電(dian)(dian)壓升高，維持輸電(dian)(dian)系統(tong)的(de)電(dian)(dian)壓穩定；

箱式(shi)變電站內串聯電抗器的作用:

1、在母線上串聯(lian)電抗器可(ke)以限制短路電流，維持母線有較高的殘壓；

2、在(zai)電(dian)容器組串(chuan)(chuan)聯(lian)電(dian)抗(kang)(kang)(kang)器，可(ke)以限(xian)制(zhi)高次諧(xie)波，降低電(dian)抗(kang)(kang)(kang)。串(chuan)(chuan)聯(lian)電(dian)抗(kang)(kang)(kang)器是電(dian)力系統無功補償裝置的(de)重要配(pei)套設(she)備。電(dian)力電(dian)容器與干式鐵芯電(dian)抗(kang)(kang)(kang)器串(chuan)(chuan)聯(lian)后，能有(you)效地抑(yi)制(zhi)電(dian)網中的(de)高次諧(xie)波，限(xian)制(zhi)合閘涌(yong)流及(ji)操作(zuo)過電(dian)壓，改善系統的(de)電(dian)壓波形，提高電(dian)網功率因數(shu)。