电(dian)机绝缘(yuan)实验(yan)主要有绝缘(yuan)电(dian)阻实验(yan)、直流耐(nai)压(ya)及漏电(dian)流实验(yan)、沟(gou)通耐(nai)压(ya)实验(yan)。电(dian)机绝缘(yuan)主要有各绕组(zu)对地绝缘(yuan)，相间绝缘(yuan)，匝(za)间绝缘(yuan)等。

1、绝缘电阻实验绝缘电阻实验

是查看(kan)电(dian)气设备绝缘状态最(zui)(zui)简(jian)洁(jie)和(he)最(zui)(zui)基本的(de)方法，此项实(shi)验是在其他实(shi)验之前进(jin)行(xing)。经过在绕组对地及绕组间加上直流(liu)电(dian)压(ya)，丈量出它的(de)体电(dian)阻(zu)和(he)外表(biao)电(dian)阻(zu)来反映绝缘材(cai)料和(he)绝缘结构的(de)缺点，以及绝缘吸(xi)潮(chao)、脏(zang)污情况，是一种无危害实(shi)验。

现场普(pu)遍运(yun)用兆欧(ou)表(biao)丈(zhang)量(liang)绝缘电(dian)阻，主要有(you) 500V 和(he) 1000V 两种标准。因(yin)为(wei)受介质吸收电(dian)流的(de)影响，兆欧(ou)表(biao)指示值(zhi)随时刻逐(zhu)渐增大，检测时通常转速在120r/min,读取施加电(dian)压后60s的(de)数值(zhi)或(huo)安(an)稳值(zhi)，作(zuo)为(wei)工程上的(de)绝缘电(dian)阻值(zhi)。劈(pi)相机绕组绝缘电(dian)阻应不(bu)低(di)于10MΩ。

2、直流高压走漏电流实验

　直流(liu)漏电(dian)(dian)流(liu)即(ji)电(dian)(dian)导电(dian)(dian)流(liu)，它有两(liang)部分组成(cheng)，一部分沿绝(jue)缘(yuan)外(wai)表(biao)发作(zuo)的(de)(de)电(dian)(dian)流(liu)，一部分是绝(jue)缘(yuan)体内的(de)(de)离子电(dian)(dian)流(liu)。在给(ji)绕组施加直流(liu)电(dian)(dian)压初期(qi)，漏电(dian)(dian)流(liu)还包含电(dian)(dian)容(rong)(rong)充放电(dian)(dian)电(dian)(dian)流(liu)和吸(xi)(xi)收(shou)电(dian)(dian)流(liu)，电(dian)(dian)容(rong)(rong)充放电(dian)(dian)电(dian)(dian)流(liu)是由绝(jue)缘(yuan)体形状、几许尺度和性质发作(zuo)电(dian)(dian)容(rong)(rong)在交(jiao)变(bian)电(dian)(dian)场(chang)下(xia)构成(cheng)的(de)(de)充放电(dian)(dian)电(dian)(dian)流(liu)，吸(xi)(xi)收(shou)电(dian)(dian)流(liu)是介质在交(jiao)变(bian)电(dian)(dian)场(chang)下(xia)重复极化发作(zuo)的(de)(de)电(dian)(dian)流(liu)。

　对漏电流实验成果进行有效剖析，找出绝缘问题，是直流漏电流实验的意图。依据现场实验得出以下总结：当走漏电流剧烈摇摆时，绝缘有开裂性缺点，此情况大部分大部分出现在槽口或许端部离地较近的当地，此外也有可能是引出线蜡管破损。当走漏电流随时刻增大，阐明绝缘有高阻性缺点和分层、松懈或许有潮气进入绝缘内部。走漏电流不成比例上升，同一相相邻实验电压下，走漏电流随电压不成比例超越 20%，则绝缘受潮或许脏污。

走漏电流在某(mou)电压(ya)值下(xia)迅速增长(即电子活动添(tian)加)，阐明绝缘(yuan)损(sun)坏严重(zhong)，有击穿的风险。各相泄(xie)流电流相差过大，缺点部位可能(neng)会远(yuan)离(li)端(duan)部，或许(xu)有脏(zang)污。

3、沟通耐压实验

　沟(gou)通耐(nai)压(ya)实(shi)(shi)(shi)验有(you)(you)称绝缘(yuan)(yuan)强度(du)实(shi)(shi)(shi)验、介电强度(du)实(shi)(shi)(shi)验，是(shi)判(pan)定(ding)电气设(she)备绝缘(yuan)(yuan)强度(du)的(de)(de)(de)最直接的(de)(de)(de)方法，是(shi)对沟(gou)通电机(ji)正常运转(zhuan)(zhuan)时的(de)(de)(de)绝缘(yuan)(yuan)的(de)(de)(de)最佳模拟(ni)。关(guan)于判(pan)别电机(ji)能(neng)否正常运转(zhuan)(zhuan)具有(you)(you)决定(ding)性的(de)(de)(de)含义，也(ye)是(shi)确保(bao)电机(ji)绝缘(yuan)(yuan)水(shui)平、防止发作绝缘(yuan)(yuan)毛病的(de)(de)(de)重要手法。它(ta)能(neng)较直流耐(nai)压(ya)实(shi)(shi)(shi)验更真实(shi)(shi)(shi)地模拟(ni)电机(ji)实(shi)(shi)(shi)践运转(zhuan)(zhuan)，查核绝缘(yuan)(yuan)材料耐(nai)受(shou)高(gao)压(ya)交(jiao)变电场的(de)(de)(de)能(neng)力。

从击(ji)(ji)穿(chuan)原(yuan)理可知，绝(jue)(jue)(jue)缘(yuan)(yuan)(yuan)材(cai)料(liao)在(zai)(zai)(zai)高压(ya)(ya)交(jiao)变(bian)(bian)电(dian)场中，内部(bu)(bu)会发(fa)(fa)作一(yi)些(xie)物理化学变(bian)(bian)化，能够有效地发(fa)(fa)现(xian)(xian)部(bu)(bu)分(fen)(fen)游离性缺(que)点(dian)及(ji)绝(jue)(jue)(jue)缘(yuan)(yuan)(yuan)老化的(de)缺(que)点(dian)。因(yin)为在(zai)(zai)(zai)沟通(tong)(tong)电(dian)压(ya)(ya)下主要(yao)按电(dian)容分(fen)(fen)压(ya)(ya)，故能有效地露(lu)出(chu)发(fa)(fa)电(dian)机槽(cao)(cao)部(bu)(bu)绝(jue)(jue)(jue)缘(yuan)(yuan)(yuan)缺(que)点(dian)和槽(cao)(cao)口处(chu)的(de)缺(que)点(dian)，是一(yi)种破坏性实(shi)验(yan)(yan)(yan)，每次(ci)实(shi)验(yan)(yan)(yan)对绝(jue)(jue)(jue)缘(yuan)(yuan)(yuan)会对绝(jue)(jue)(jue)缘(yuan)(yuan)(yuan)造(zao)出(chu)损伤并累积。绝(jue)(jue)(jue)缘(yuan)(yuan)(yuan)材(cai)料(liao)内部(bu)(bu)的(de)一(yi)些(xie)危险(xian)和缺(que)点(dian)能从沟通(tong)(tong)耐压(ya)(ya)实(shi)验(yan)(yan)(yan)中露(lu)出(chu)出(chu)来(lai)，因(yin)此在(zai)(zai)(zai)进行(xing)沟通(tong)(tong)耐压(ya)(ya)实(shi)验(yan)(yan)(yan)时(shi)，每次(ci)实(shi)验(yan)(yan)(yan)电(dian)压(ya)(ya)需(xu)降到前次(ci)实(shi)验(yan)(yan)(yan)电(dian)压(ya)(ya)的(de)70%-80%。在(zai)(zai)(zai)沟通(tong)(tong)电(dian)机绝(jue)(jue)(jue)缘(yuan)(yuan)(yuan)实(shi)验(yan)(yan)(yan)时(shi)，只有当绝(jue)(jue)(jue)缘(yuan)(yuan)(yuan)电(dian)阻实(shi)验(yan)(yan)(yan)及(ji)直流耐压(ya)(ya)实(shi)验(yan)(yan)(yan)和直流漏电(dian)流实(shi)验(yan)(yan)(yan)合格(ge)后方可进行(xing)沟通(tong)(tong)实(shi)验(yan)(yan)(yan)。现(xian)(xian)场要(yao)求电(dian)机接受 1 分(fen)(fen)钟 2000V 工频(pin)沟通(tong)(tong)耐压(ya)(ya)实(shi)验(yan)(yan)(yan)，而且(qie)无(wu)闪络(luo)、击(ji)(ji)穿(chuan)现(xian)(xian)象。

4、直流高压走漏实验和沟通耐压实验的异同

　沟(gou)通(tong)、直(zhi)(zhi)流电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)在(zai)绝(jue)(jue)缘(yuan)(yuan)层(ceng)中的散(san)布(bu)不(bu)同(tong)，直(zhi)(zhi)流电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)是按电(dian)(dian)(dian)(dian)导散(san)布(bu)的，反映绝(jue)(jue)缘(yuan)(yuan)内(nei)单(dan)个部分(fen)可能发作(zuo)(zuo)过电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)的情况;沟(gou)通(tong)电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)是按与绝(jue)(jue)缘(yuan)(yuan)电(dian)(dian)(dian)(dian)阻并存的散(san)布(bu)电(dian)(dian)(dian)(dian)容成反比散(san)布(bu)的，反映遍地散(san)布(bu)电(dian)(dian)(dian)(dian)容部分(fen)可能发作(zuo)(zuo)过电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)的情况。别的，绝(jue)(jue)缘(yuan)(yuan)在(zai)直(zhi)(zhi)流电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)作(zuo)(zuo)用下耐(nai)压(ya)(ya)(ya)强度比在(zai)沟(gou)通(tong)电(dian)(dian)(dian)(dian)压(ya)(ya)(ya)下要高。所以，沟(gou)通(tong)耐(nai)压(ya)(ya)(ya)实(shi)验与直(zhi)(zhi)流耐(nai)压(ya)(ya)(ya)实(shi)验不(bu)能彼此(ci)替代。

电机维(wei)修介(jie)绍JP402A型异步劈相(xiang)(xiang)(xiang)机(ji)(ji)(ji)是一种(zhong)结构(gou)复(fu)杂、用处(chu)特别的(de)(de)三(san)相(xiang)(xiang)(xiang)异步电(dian)(dian)机(ji)(ji)(ji),在电(dian)(dian)力机(ji)(ji)(ji)车辅佐系统(tong)中将单相(xiang)(xiang)(xiang)电(dian)(dian)源转变成三(san)相(xiang)(xiang)(xiang)电(dian)(dian)源,为各辅佐电(dian)(dian)动(dong)机(ji)(ji)(ji)供给三(san)相(xiang)(xiang)(xiang)电(dian)(dian)源。劈相(xiang)(xiang)(xiang)机(ji)(ji)(ji)供电(dian)(dian)时,电(dian)(dian)压(ya)动(dong)摇规模大、三(san)相(xiang)(xiang)(xiang)电(dian)(dian)压(ya)和电(dian)(dian)流不对称。劈相(xiang)(xiang)(xiang)机(ji)(ji)(ji)能(neng)否正常(chang)工作取(qu)决于(yu)它的(de)(de)三(san)相(xiang)(xiang)(xiang)定(ding)子绕组、定(ding)子铁芯和轴承三(san)大件,三(san)相(xiang)(xiang)(xiang)定(ding)子绕组对铁芯及三(san)相(xiang)(xiang)(xiang)绕组间的(de)(de)彼此绝(jue)缘是电(dian)(dian)机(ji)(ji)(ji)正常(chang)运(yun)(yun)转的(de)(de)关键。为确保(bao)电(dian)(dian)机(ji)(ji)(ji)出厂后能(neng)牢靠的(de)(de)运(yun)(yun)转,提高电(dian)(dian)机(ji)(ji)(ji)运(yun)(yun)用寿命(ming),需要(yao)在电(dian)(dian)机(ji)(ji)(ji)出厂前做若干绝(jue)缘预防性实验,以便掌握其绝(jue)缘情况(kuang),并(bing)能(neng)及时发现绝(jue)缘内部(bu)躲藏的(de)(de)缺点,加(jia)以消除,严重(zhong)者有必要(yao)替换绝(jue)缘系统(tong)以免在运(yun)(yun)转中发作绝(jue)缘击穿,造(zao)出机(ji)(ji)(ji)车机(ji)(ji)(ji)破事(shi)端(duan)或许不可挽回(hui)的(de)(de)损失。