1、型式和接線選擇

根據測量表計、變送器(qi)和繼電器(qi)等負荷要求，及結合電壓互感器(qi)型式和接線進行選擇。

1)兩個單(dan)相電(dian)壓(ya)互感(gan)器Vv接(jie)線(xian)方式(shi)。用于表計(ji)和繼電(dian)器接(jie)入兩相間電(dian)壓(ya)的情況。電(dian)壓(ya)互感(gan)器一次繞(rao)組不能接(jie)地。這種(zhong)接(jie)線(xian)方式(shi)用于中性點(dian)不接(jie)地系(xi)統或(huo)中性點(dian)絕(jue)緣諧(xie)振接(jie)地系(xi)統的電(dian)網(wang)中。

2)三個單相電(dian)(dian)(dian)壓(ya)(ya)(ya)互感(gan)器接(jie)成星形-星形接(jie)線方式。電(dian)(dian)(dian)壓(ya)(ya)(ya)互感(gan)器一次繞(rao)組和(he)二(er)次繞(rao)組的中性(xing)點直接(jie)接(jie)地，用于供電(dian)(dian)(dian)給(gei)要求電(dian)(dian)(dian)壓(ya)(ya)(ya)的表計和(he)繼電(dian)(dian)(dian)器以及供電(dian)(dian)(dian)給(gei)絕緣檢查(cha)電(dian)(dian)(dian)壓(ya)(ya)(ya)表。如(ru)高壓(ya)(ya)(ya)側系(xi)統中性(xing)點直接(jie)接(jie)地，可接(jie)入相電(dian)(dian)(dian)壓(ya)(ya)(ya)測量(liang)表計。如(ru)高壓(ya)(ya)(ya)側系(xi)統中性(xing)點不接(jie)地或(huo)經阻抗接(jie)地，則不允(yun)許(xu)接(jie)入測量(liang)相電(dian)(dian)(dian)壓(ya)(ya)(ya)的表計。

3)三(san)相三(san)柱式(shi)電(dian)(dian)壓(ya)互感(gan)器星形接(jie)線方式(shi)。用于接(jie)入線電(dian)(dian)壓(ya)和相對電(dian)(dian)網中性(xing)點的相電(dian)(dian)壓(ya)。這種電(dian)(dian)壓(ya)互感(gan)器一(yi)般用于中性(xing)點不接(jie)地(di)系(xi)統(tong)或經消(xiao)弧線圈接(jie)地(di)的電(dian)(dian)網。需(xu)要注意的是，一(yi)次(ci)繞組(zu)中性(xing)點不允許接(jie)地(di)。

4)三相(xiang)五柱(zhu)式(shi)電(dian)(dian)(dian)壓互感器(qi)星形接(jie)(jie)線方(fang)式(shi)。三相(xiang)五柱(zhu)式(shi)電(dian)(dian)(dian)壓互感器(qi)是磁系(xi)統具有(you)五個磁柱(zhu)的三相(xiang)三繞組的電(dian)(dian)(dian)壓互感器(qi)。一次(ci)繞組和主二次(ci)繞組接(jie)(jie)成中(zhong)性點直接(jie)(jie)接(jie)(jie)地的星形，輔(fu)助(zhu)二次(ci)繞組接(jie)(jie)成有(you)零序(xu)電(dian)(dian)(dian)壓回路(lu)的接(jie)(jie)線方(fang)式(shi)，用于將(jiang)測量表(biao)計和繼電(dian)(dian)(dian)器(qi)接(jie)(jie)入(ru)線電(dian)(dian)(dian)壓和相(xiang)電(dian)(dian)(dian)壓，接(jie)(jie)成零序(xu)的輔(fu)助(zhu)二次(ci)繞組接(jie)(jie)入(ru)接(jie)(jie)地保(bao)護裝置(zhi)或(huo)繼電(dian)(dian)(dian)器(qi)。

2、準確級選擇

電(dian)壓(ya)互感器除剩余電(dian)壓(ya)繞組外(wai)，應給出響應的測量準確級和保(bao)護準確級。

1)測量用電(dian)壓互感器(qi)的(de)(de)準確級(ji)，是(shi)以準確級(ji)規定的(de)(de)電(dian)壓和負荷范圍內(nei)的(de)(de)大允許電(dian)壓誤差百分數來標(biao)(biao)稱。標(biao)(biao)準準確及為(wei)0.1、0.2、0.5、1.0、3.0。

2)保護用(yong)電(dian)(dian)壓(ya)互感器的(de)準(zhun)確級，是以該準(zhun)確級在5%額(e)定電(dian)(dian)壓(ya)到(dao)額(e)定電(dian)(dian)壓(ya)因數相對應的(de)電(dian)(dian)壓(ya)范(fan)圍內大(da)允許電(dian)(dian)壓(ya)誤差的(de)百分數標(biao)稱，其(qi)后(hou)標(biao)以字母“P”。標(biao)準(zhun)準(zhun)確級為3P和6P

3)保護用電壓互感器剩余電壓繞組的準確(que)級為6P。

4)電壓誤(wu)差和相(xiang)位差的限值(zhi)。各(ge)準確級的測量用電壓互感器和保護用電壓互感器，其電壓誤(wu)差和相(xiang)位差不應超過限值(zhi)。

5)測量(liang)用(yong)電(dian)壓(ya)互感器準(zhun)確(que)級選擇。測量(liang)用(yong)電(dian)壓(ya)互感器的準(zhun)確(que)級應與測量(liang)儀(yi)表的準(zhun)確(que)級相適應。