繼(ji)電(dian)保(bao)護教材發電(dian)機(ji)保(bao)護第七章(zhang)作者：匿名2007/12/28 233333633333

較(jiao)好節(jie)通道(dao)：關鍵(jian)詞：總結發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)的(de)(de)(de)(de)(de)(de)安全運(yun)行(xing)對(dui)(dui)保(bao)(bao)(bao)證電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)力(li)系(xi)統的(de)(de)(de)(de)(de)(de)正常(chang)運(yun)行(xing)和電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)能(neng)(neng)質量起著決定(ding)(ding)(ding)性(xing)的(de)(de)(de)(de)(de)(de)作用。同時(shi)(shi)(shi)(shi)，發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)本身也(ye)是非常(chang)有(you)價值(zhi)的(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)氣元(yuan)件。因(yin)(yin)此，對(dui)(dui)于各種(zhong)故障(zhang)(zhang)和異(yi)(yi)常(chang)工況(kuang)，應(ying)(ying)安裝性(xing)能(neng)(neng)完(wan)善的(de)(de)(de)(de)(de)(de)繼電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)裝置。一(yi)(yi)、故障(zhang)(zhang)類(lei)型及(ji)異(yi)(yi)常(chang)運(yun)行(xing)狀態：1。故障(zhang)(zhang)類(lei)型1)定(ding)(ding)(ding)子(zi)(zi)(zi)(zi)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)相(xiang)(xiang)(xiang)間(jian)短(duan)(duan)(duan)路(lu)(lu)(lu)(lu)：危(wei)害較(jiao)大2)定(ding)(ding)(ding)子(zi)(zi)(zi)(zi)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)一(yi)(yi)相(xiang)(xiang)(xiang)匝間(jian)短(duan)(duan)(duan)路(lu)(lu)(lu)(lu)：可(ke)能(neng)(neng)發(fa)(fa)(fa)展(zhan)為單(dan)(dan)(dan)相(xiang)(xiang)(xiang)接(jie)(jie)(jie)(jie)(jie)地(di)(di)短(duan)(duan)(duan)路(lu)(lu)(lu)(lu)和相(xiang)(xiang)(xiang)間(jian)短(duan)(duan)(duan)路(lu)(lu)(lu)(lu)3)定(ding)(ding)(ding)子(zi)(zi)(zi)(zi)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)單(dan)(dan)(dan)相(xiang)(xiang)(xiang)接(jie)(jie)(jie)(jie)(jie)地(di)(di)：常(chang)見(jian)，可(ke)能(neng)(neng)造(zao)成(cheng)鐵芯燒(shao)損或(huo)局(ju)部熔化(hua)(hua)4)轉(zhuan)(zhuan)子(zi)(zi)(zi)(zi)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)一(yi)(yi)點接(jie)(jie)(jie)(jie)(jie)地(di)(di)或(huo)兩(liang)(liang)(liang)點接(jie)(jie)(jie)(jie)(jie)地(di)(di)：一(yi)(yi)點接(jie)(jie)(jie)(jie)(jie)地(di)(di)時(shi)(shi)(shi)(shi)危(wei)害不(bu)(bu)(bu)嚴重；兩(liang)(liang)(liang)點接(jie)(jie)(jie)(jie)(jie)地(di)(di)時(shi)(shi)(shi)(shi)，轉(zhuan)(zhuan)子(zi)(zi)(zi)(zi)磁(ci)(ci)通平衡(heng)被(bei)破壞(huai)，可(ke)能(neng)(neng)引(yin)(yin)(yin)(yin)起發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)強烈振(zhen)動(dong)或(huo)燒(shao)壞(huai)轉(zhuan)(zhuan)子(zi)(zi)(zi)(zi)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)。5)轉(zhuan)(zhuan)子(zi)(zi)(zi)(zi)勵磁(ci)(ci)回路(lu)(lu)(lu)(lu)勵磁(ci)(ci)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)急(ji)劇下降或(huo)消失(shi)：系(xi)統吸收無(wu)功(gong)(gong)功(gong)(gong)率(lv)，導(dao)(dao)致失(shi)步，從(cong)而導(dao)(dao)致系(xi)統電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)下降，甚至(zhi)系(xi)統崩(beng)潰(kui)。2.異(yi)(yi)常(chang)運(yun)行(xing)狀態1)外(wai)部短(duan)(duan)(duan)路(lu)(lu)(lu)(lu)引(yin)(yin)(yin)(yin)起的(de)(de)(de)(de)(de)(de)定(ding)(ding)(ding)子(zi)(zi)(zi)(zi)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)過(guo)(guo)(guo)(guo)流(liu)(liu)：溫(wen)升(sheng)、絕緣老化(hua)(hua)2)負(fu)荷(he)超過(guo)(guo)(guo)(guo)發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)額定(ding)(ding)(ding)容量引(yin)(yin)(yin)(yin)起的(de)(de)(de)(de)(de)(de)三相(xiang)(xiang)(xiang)對(dui)(dui)稱(cheng)過(guo)(guo)(guo)(guo)載(zai)(zai)：溫(wen)升(sheng)、絕緣老化(hua)(hua)3)外(wai)部不(bu)(bu)(bu)對(dui)(dui)稱(cheng)短(duan)(duan)(duan)路(lu)(lu)(lu)(lu)或(huo)負(fu)載(zai)(zai)不(bu)(bu)(bu)對(dui)(dui)稱(cheng)引(yin)(yin)(yin)(yin)起的(de)(de)(de)(de)(de)(de)發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)負(fu)序(xu)過(guo)(guo)(guo)(guo)流(liu)(liu)和過(guo)(guo)(guo)(guo)載(zai)(zai)：轉(zhuan)(zhuan)子(zi)(zi)(zi)(zi)中感應(ying)(ying)出(chu)100hz的(de)(de)(de)(de)(de)(de)倍頻電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)，可(ke)能(neng)(neng)引(yin)(yin)(yin)(yin)起轉(zhuan)(zhuan)子(zi)(zi)(zi)(zi)局(ju)部燒(shao)傷或(huo)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)環放熱，造(zao)成(cheng)發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)嚴重事故。此外(wai)，還會引(yin)(yin)(yin)(yin)起發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)100hz的(de)(de)(de)(de)(de)(de)振(zhen)動(dong)。4)突(tu)然甩(shuai)負(fu)荷(he)引(yin)(yin)(yin)(yin)起定(ding)(ding)(ding)子(zi)(zi)(zi)(zi)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)過(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)：調速系(xi)統慣性(xing)大時(shi)(shi)(shi)(shi)，可(ke)能(neng)(neng)發(fa)(fa)(fa)生(sheng)過(guo)(guo)(guo)(guo)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)，導(dao)(dao)致發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)絕緣擊穿。5)勵磁(ci)(ci)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)(lu)故障(zhang)(zhang)或(huo)長(chang)時(shi)(shi)(shi)(shi)間(jian)強勵引(yin)(yin)(yin)(yin)起轉(zhuan)(zhuan)子(zi)(zi)(zi)(zi)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)過(guo)(guo)(guo)(guo)載(zai)(zai)；6)汽(qi)輪機(ji)(ji)(ji)(ji)(ji)(ji)主(zhu)汽(qi)門突(tu)然關閉引(yin)(yin)(yin)(yin)起的(de)(de)(de)(de)(de)(de)發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)逆(ni)功(gong)(gong)率(lv)：當(dang)(dang)發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)因(yin)(yin)爐膛(tang)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)或(huo)調速回路(lu)(lu)(lu)(lu)故障(zhang)(zhang)及(ji)某(mou)些人為因(yin)(yin)素切(qie)換到電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)運(yun)行(xing)時(shi)(shi)(shi)(shi)，發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)會從(cong)系(xi)統中吸收有(you)功(gong)(gong)功(gong)(gong)率(lv)，即(ji)逆(ni)功(gong)(gong)率(lv)。2.保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)類(lei)型：1。發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)縱差(cha)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)：定(ding)(ding)(ding)子(zi)(zi)(zi)(zi)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)及(ji)其出(chu)線2相(xiang)(xiang)(xiang)間(jian)短(duan)(duan)(duan)路(lu)(lu)(lu)(lu)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)。橫向差(cha)動(dong)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)：定(ding)(ding)(ding)子(zi)(zi)(zi)(zi)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)3單(dan)(dan)(dan)相(xiang)(xiang)(xiang)匝間(jian)短(duan)(duan)(duan)路(lu)(lu)(lu)(lu)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)。單(dan)(dan)(dan)相(xiang)(xiang)(xiang)接(jie)(jie)(jie)(jie)(jie)地(di)(di)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)：發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)定(ding)(ding)(ding)子(zi)(zi)(zi)(zi)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)4單(dan)(dan)(dan)相(xiang)(xiang)(xiang)接(jie)(jie)(jie)(jie)(jie)地(di)(di)短(duan)(duan)(duan)路(lu)(lu)(lu)(lu)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)。發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)失(shi)磁(ci)(ci)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)：對(dui)(dui)轉(zhuan)(zhuan)子(zi)(zi)(zi)(zi)勵磁(ci)(ci)回路(lu)(lu)(lu)(lu)5勵磁(ci)(ci)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)急(ji)劇下降或(huo)消失(shi)的(de)(de)(de)(de)(de)(de)響(xiang)應(ying)(ying)。過(guo)(guo)(guo)(guo)流(liu)(liu)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)：對(dui)(dui)外(wai)部短(duan)(duan)(duan)路(lu)(lu)(lu)(lu)引(yin)(yin)(yin)(yin)起的(de)(de)(de)(de)(de)(de)過(guo)(guo)(guo)(guo)流(liu)(liu)的(de)(de)(de)(de)(de)(de)響(xiang)應(ying)(ying)。同時(shi)(shi)(shi)(shi)也(ye)作為縱差(cha)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)的(de)(de)(de)(de)(de)(de)后備保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)。6.負(fu)序(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)：當(dang)(dang)反作用不(bu)(bu)(bu)對(dui)(dui)稱(cheng)短(duan)(duan)(duan)路(lu)(lu)(lu)(lu)或(huo)三相(xiang)(xiang)(xiang)負(fu)載(zai)(zai)不(bu)(bu)(bu)對(dui)(dui)稱(cheng)時(shi)(shi)(shi)(shi)，發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)定(ding)(ding)(ding)子(zi)(zi)(zi)(zi)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)7中的(de)(de)(de)(de)(de)(de)負(fu)序(xu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)。過(guo)(guo)(guo)(guo)載(zai)(zai)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)：發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)長(chang)期(qi)超過(guo)(guo)(guo)(guo)額定(ding)(ding)(ding)負(fu)荷(he)運(yun)行(xing)時(shi)(shi)(shi)(shi)的(de)(de)(de)(de)(de)(de)信號保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)8。過(guo)(guo)(guo)(guo)壓(ya)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)：突(tu)然甩(shuai)負(fu)荷(he)引(yin)(yin)(yin)(yin)起的(de)(de)(de)(de)(de)(de)過(guo)(guo)(guo)(guo)壓(ya)9。轉(zhuan)(zhuan)子(zi)(zi)(zi)(zi)一(yi)(yi)點接(jie)(jie)(jie)(jie)(jie)地(di)(di)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)和兩(liang)(liang)(liang)點接(jie)(jie)(jie)(jie)(jie)地(di)(di)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)：勵磁(ci)(ci)回路(lu)(lu)(lu)(lu)10的(de)(de)(de)(de)(de)(de)接(jie)(jie)(jie)(jie)(jie)地(di)(di)故障(zhang)(zhang)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)。轉(zhuan)(zhuan)子(zi)(zi)(zi)(zi)過(guo)(guo)(guo)(guo)載(zai)(zai)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)：11。逆(ni)功(gong)(gong)率(lv)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)：當(dang)(dang)汽(qi)輪機(ji)(ji)(ji)(ji)(ji)(ji)主(zhu)汽(qi)閥誤關，發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)出(chu)口斷路(lu)(lu)(lu)(lu)器(qi)未跳(tiao)閘(zha)時(shi)(shi)(shi)(shi)，發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)失(shi)去動(dong)力(li)，變成(cheng)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)動(dong)機(ji)(ji)(ji)(ji)(ji)(ji)運(yun)行(xing)，從(cong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)力(li)系(xi)統吸收有(you)功(gong)(gong)功(gong)(gong)率(lv)危(wei)險：汽(qi)輪機(ji)(ji)(ji)(ji)(ji)(ji)尾葉片可(ke)能(neng)(neng)過(guo)(guo)(guo)(guo)熱，造(zao)成(cheng)事故。第(di)二節(jie)發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)縱差(cha)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)一(yi)(yi)、功(gong)(gong)能(neng)(neng)原理(li)下圖為發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)縱差(cha)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)單(dan)(dan)(dan)相(xiang)(xiang)(xiang)原理(li)圖。當(dang)(dang)兩(liang)(liang)(liang)組(zu)(zu)(zu)(zu)(zu)的(de)(de)(de)(de)(de)(de)CT特性(xing)和變比(bi)一(yi)(yi)致時(shi)(shi)(shi)(shi)，在正常(chang)區域外(wai)接(jie)(jie)(jie)(jie)(jie)地(di)(di)時(shi)(shi)(shi)(shi)，可(ke)以(yi)選擇CT特性(xing)盡量一(yi)(yi)致。不(bu)(bu)(bu)平衡(heng)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)比(bi)干式變壓(ya)器(qi)小。計算兩(liang)(liang)(liang)個閾(yu)值(zhi)：(1)避免外(wai)部短(duan)(duan)(duan)路(lu)(lu)(lu)(lu)；(2)避免大于發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)額定(ding)(ding)(ding)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)的(de)(de)(de)(de)(de)(de)出(chu)口兩(liang)(liang)(liang)相(xiang)(xiang)(xiang)短(duan)(duan)(duan)路(lu)(lu)(lu)(lu)(CT第(di)二次斷開(kai)時(shi)(shi)(shi)(shi))。第(di)三節(jie)發(fa)(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(ji)(ji)(ji)橫向差(cha)動(dong)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)當(dang)(dang)一(yi)(yi)相(xiang)(xiang)(xiang)定(ding)(ding)(ding)子(zi)(zi)(zi)(zi)繞(rao)(rao)(rao)(rao)組(zu)(zu)(zu)(zu)(zu)有(you)兩(liang)(liang)(liang)個或(huo)兩(liang)(liang)(liang)個以(yi)上并聯支(zhi)路(lu)(lu)(lu)(lu)時(shi)(shi)(shi)(shi)，安裝該(gai)保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)正常(chang)：間(jian)接(jie)(jie)(jie)(jie)(jie)轉(zhuan)(zhuan)向：死區：(1)同支(zhi)路(lu)(lu)(lu)(lu)：保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)固定(ding)(ding)(ding)；(2)同相(xiang)(xiang)(xiang)支(zhi)路(lu)(lu)(lu)(lu)：保(bao)(bao)(bao)護(hu)(hu)(hu)(hu)固定(ding)(ding)(ding)；(3)纏繞(rao)(rao)(rao)(rao) 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第(di)(di)四節(jie)發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)單相接(jie)(jie)地保(bao)(bao)護(hu)(hu)(hu)一(yi)、發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)定(ding)子繞組(zu)單相接(jie)(jie)地的(de)(de)特(te)(te)點(dian)(dian)定(ding)子繞組(zu)中(zhong)性(xing)點(dian)(dian)不(bu)接(jie)(jie)地或經高(gao)(gao)阻接(jie)(jie)地是較常(chang)見的(de)(de)故(gu)障(zhang)之一(yi)。它(ta)具有一(yi)般不(bu)接(jie)(jie)地系統(tong)單相接(jie)(jie)地短(duan)路(lu)(lu)的(de)(de)特(te)(te)點(dian)(dian)。如果A遠(yuan)離中(zhong)性(xing)點(dian)(dian)，單相接(jie)(jie)地發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)中(zhong)性(xing)點(dian)(dian)會發(fa)(fa)生(sheng)位移，產生(sheng)零(ling)(ling)(ling)(ling)(ling)序(xu)(xu)(xu)(xu)電(dian)(dian)(dian)(dian)壓(ya)(ya)。各(ge)故(gu)障(zhang)點(dian)(dian)相對(dui)(dui)(dui)(dui)地電(dian)(dian)(dian)(dian)壓(ya)(ya)：故(gu)障(zhang)點(dian)(dian)零(ling)(ling)(ling)(ling)(ling)序(xu)(xu)(xu)(xu)電(dian)(dian)(dian)(dian)壓(ya)(ya)為(wei)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)分(fen)布(bu)：見上(shang)頁：2。發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)定(ding)子單相接(jie)(jie)地保(bao)(bao)護(hu)(hu)(hu)使用(yong)的(de)(de)基(ji)波(bo)零(ling)(ling)(ling)(ling)(ling)序(xu)(xu)(xu)(xu)分(fen)量取決于(yu)大小(xiao)(xiao)(xiao)(xiao)。發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)直接(jie)(jie)接(jie)(jie)母(mu)線(xian)(xian)時(shi)(shi)，——零(ling)(ling)(ling)(ling)(ling)序(xu)(xu)(xu)(xu)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)保(bao)(bao)護(hu)(hu)(hu)動(dong)作(zuo)(zuo)跳(tiao)閘，(發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)-變壓(ya)(ya)器組(zu))允(yun)許(xu)(xu)值為(wei)——零(ling)(ling)(ling)(ling)(ling)序(xu)(xu)(xu)(xu)電(dian)(dian)(dian)(dian)壓(ya)(ya)保(bao)(bao)護(hu)(hu)(hu)，作(zuo)(zuo)用(yong)于(yu)信(xin)號(hao)(1)基(ji)波(bo)零(ling)(ling)(ling)(ling)(ling)序(xu)(xu)(xu)(xu)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)保(bao)(bao)護(hu)(hu)(hu)對(dui)(dui)(dui)(dui)C的(de)(de)要求：(1)三相對(dui)(dui)(dui)(dui)稱負(fu)(fu)(fu)(fu)載。(小(xiao)(xiao)(xiao)(xiao))輸出功率足夠小(xiao)(xiao)(xiao)(xiao)。一(yi)般的(de)(de)C達(da)不(bu)到足夠的(de)(de)靈敏度，帶交流(liu)(liu)(liu)(liu)(liu)(liu)助磁(ci)的(de)(de)C得到了廣泛(fan)的(de)(de)應(ying)用(yong)。(2)基(ji)波(bo)零(ling)(ling)(ling)(ling)(ling)序(xu)(xu)(xu)(xu)電(dian)(dian)(dian)(dian)壓(ya)(ya)保(bao)(bao)護(hu)(hu)(hu)整(zheng)定(ding)隱藏在(zai)高(gao)(gao)壓(ya)(ya)側，發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)側一(yi)般15~30V有死區100定(ding)子接(jie)(jie)地保(bao)(bao)護(hu)(hu)(hu)：零(ling)(ling)(ling)(ling)(ling)序(xu)(xu)(xu)(xu)電(dian)(dian)(dian)(dian)壓(ya)(ya)保(bao)(bao)護(hu)(hu)(hu)增加支路(lu)(lu)電(dian)(dian)(dian)(dian)壓(ya)(ya)和固定(ding)工頻偏移電(dian)(dian)(dian)(dian)壓(ya)(ya)保(bao)(bao)護(hu)(hu)(hu)方式，采(cai)用(yong)三次諧波(bo)電(dian)(dian)(dian)(dian)壓(ya)(ya)。第(di)(di)五(wu)節(jie)發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)負(fu)(fu)(fu)(fu)序(xu)(xu)(xu)(xu)過(guo)(guo)流(liu)(liu)(liu)(liu)(liu)(liu)保(bao)(bao)護(hu)(hu)(hu)一(yi)、負(fu)(fu)(fu)(fu)序(xu)(xu)(xu)(xu)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)保(bao)(bao)護(hu)(hu)(hu)的(de)(de)作(zuo)(zuo)用(yong)：——轉子過(guo)(guo)熱，機(ji)(ji)械振動(dong)為(wei)了防止轉子過(guo)(guo)熱，——負(fu)(fu)(fu)(fu)序(xu)(xu)(xu)(xu)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)標準值表示為(wei)發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)額定(ding)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)的(de)(de)倍數，A——允(yun)許(xu)(xu)過(guo)(guo)熱時(shi)(shi)間常(chang)數曲線(xian)(xian)表明發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)允(yun)許(xu)(xu)負(fu)(fu)(fu)(fu)序(xu)(xu)(xu)(xu)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)的(de)(de)時(shi)(shi)間隨大小(xiao)(xiao)(xiao)(xiao)而變化，故(gu)稱反(fan)時(shi)(shi)限(xian)(xian)。針(zhen)對(dui)(dui)(dui)(dui)這種情況，安(an)裝發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)負(fu)(fu)(fu)(fu)序(xu)(xu)(xu)(xu)過(guo)(guo)流(liu)(liu)(liu)(liu)(liu)(liu)保(bao)(bao)護(hu)(hu)(hu)。2.負(fu)(fu)(fu)(fu)序(xu)(xu)(xu)(xu)過(guo)(guo)流(liu)(liu)(liu)(liu)(liu)(liu)保(bao)(bao)護(hu)(hu)(hu)兩級(ji)一(yi)段(duan)(duan)在(zai)跳(tiao)閘二段(duan)(duan)延(yan)時(shi)(shi)，在(zai)信(xin)號(hao)分(fen)析(xi)延(yan)時(shi)(shi)。(1)ab段(duan)(duan)，對(dui)(dui)(dui)(dui)發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)不(bu)安(an)全(quan)。(2)在(zai)bc段(duan)(duan)，發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)對(dui)(dui)(dui)(dui)的(de)(de)承載能(neng)力沒有得到充分(fen)利用(yong)。(3)信(xin)號(hao)在(zai)cd段(duan)(duan)發(fa)(fa)送，但(dan)由于(yu)操(cao)(cao)作(zuo)(zuo)人(ren)員(yuan)的(de)(de)操(cao)(cao)作(zuo)(zuo)，當信(xin)號(hao)接(jie)(jie)近該點(dian)(dian)時(shi)(shi)，就不(bu)安(an)全(quan)。(4)在(zai)de段(duan)(duan)第(di)(di)三，負(fu)(fu)(fu)(fu)序(xu)(xu)(xu)(xu)反(fan)時(shi)(shi)限(xian)(xian)過(guo)(guo)流(liu)(liu)(liu)(liu)(liu)(liu)保(bao)(bao)護(hu)(hu)(hu)或——校(xiao)正常(chang)數(考(kao)慮轉子冷卻閾值)第(di)(di)六節(jie)發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)失磁(ci)保(bao)(bao)護(hu)(hu)(hu)一(yi)、發(fa)(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)失磁(ci)運(yun)行及其影響失磁(ci)故(gu)障(zhang)是指勵(li)(li)(li)(li)磁(ci)突然消失或部分(fen)消失(低(di)勵(li)(li)(li)(li)磁(ci))。勵(li)(li)(li)(li)磁(ci)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu)低(di)于(yu)靜(jing)態(tai)穩定(ding)極限(xian)(xian)對(dui)(dui)(dui)(dui)應(ying)的(de)(de)勵(li)(li)(li)(li)磁(ci)電(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(liu)(liu)(liu))1失磁(ci)原因(yin)：三種(1)勵(li)(li)(li)(li)磁(ci)回(hui)路(lu)(lu)開(kai)路(lu)(lu)，勵(li)(li)(li)(li)磁(ci)繞組(zu)斷線(xian)(xian)誤(wu)操(cao)(cao)作(zuo)(zuo)，勵(li)(li)(li)(li)磁(ci)開(kai)關(guan)誤(wu)操(cao)(cao)作(zuo)(zuo)，勵(li)(li)(li)(li)磁(ci)調節(jie)裝置自(zi)動(dong)開(kai)關(guan)誤(wu)操(cao)(cao)作(zuo)(zuo)。

置中部分元件損壞（2）勵磁繞組由于長期發熱，絕緣老化或損壞引起短路（3）運行人員調整等。發電機失磁后，它的各種電氣量和機械量都會發生變化，且將危及發電機和系統的安全。2失磁后的基本物理過程：依據：功角特性關系：轉子運動方程：——原動機功率——同步功率——異步功率——電氣角加速度——機組的慣性時間常數（1）不變當發電機未失步——同步振蕩階段（靜穩定極限角）——臨界失步狀態轉子加速愈趨劇烈異步運行階段，這時原動機的調速裝置在轉子加速的影響下，使汽門關小，（2）當時，即從系統吸收感性無功功率，，吸收圖圓為發電機以不同的有功功率P臨界失步時，機端測量阻抗的軌跡，圓內為失步區。在發電機超過同步轉速后，轉子回路中將感應出頻率為電流，（發電機轉速的頻率，系統頻率）該電流將產生異步功率當即進入穩態的異步運行階段。3．失磁后的影響：對電力系統：(1)吸收Q無功儲備不足，將因電壓崩潰而瓦解(2)(3)失磁失步振蕩甩負荷對發電機（1）轉子中的差頻電流過熱（2）轉差率吸定子過電流發熱（3）轉速振動氣輪發電機：較大s 0.5可穩定運行.——可異步運行一段時間水輪發電機較小s很大發熱厲害，故不允許失磁異步運行可見：失磁后，若不失步，無直接危害。失步后，對發電機及系統有不利影響。故應裝設失磁保護。二、失磁發電機機端測量阻抗的變化軌跡通常采用等有功阻抗圓。等無功圓（臨界失步阻抗圓）和等電壓阻抗圓來分析。（一）等有功阻抗圓：失步前。P基本不變———等有功過程圓的方程式特點：（1）圓的大小與P有關圓（2）失磁前，發電機向系統送無功，Q為正，位與第Ⅰ象限失磁后，隨Q的變化，Q由正負，從ⅠⅣ象限，圓越小，從ⅠⅣ快。（3）圓的位置與j有關，若=0，圓心在實軸上，很容易進入第Ⅳ象限可見，失磁后，向第四象限移動，且較終將穩定在第四象限內（二）等無功阻抗圓（臨界失步圓）常數圓周為發電機以不同的有功功率P臨界失步時，機端測量阻抗的軌跡，圓內為失步區。（三）臨界電壓阻抗圓臨界電壓值：發電機失磁后，系統某一點電壓下降到是機組不能穩定運行，此電壓值稱為臨界電壓值（整理后：三、失磁保護的主要判據 來源：中電力資料網#p#分頁標題#e#