变压器中性点并联保护间隙距离确定方法研究  

Research on the Method of Determining the Gap Distance of Parallel Protection for Transformer Neutral Point

作　　者：戴何笠 刘能[2] 王旭[3] 杨鑫[1] 曾玲丽[1] 

机构地区：[1]长沙理工大学电气与信息工程学院,长沙410114 [2]国网浙江省电力公司新昌县供电公司,浙江新昌312500 [3]国网河南省电力公司开封供电公司,河南开封475000

出　　处：《电瓷避雷器》2017年第3期147-152,共6页Insulators and Surge Arresters

摘　　要：变压器中性点常采用避雷器与放电间隙相并联方式来保护中性点绝缘,但由于间隙放电的分散性,使得其配合困难从而常导致间隙误放电和拒放电。为了防止误放电和拒放电,准确地确定间隙的距离是绝缘配合的关键,最好的方法是绘制伏秒特性曲线,但此曲线绘制工作量过于繁杂。因此,提出运用正态概率分布,对雷电冲击放电和工频放电数据进行分析,选取间隙距离的方法,减小了间隙误放电和拒放电的概率,提高变压器中性点绝缘保护能力和供电可靠性。并应用该方法对金属氧化物避雷器并联保护间隙装置进行放电试验对比,试验证明了该方法是准确、有效的。The discharge gap parallel arrester is often used to protect the transformer neutral point insulation. But due to the dispersion of the gap discharge, it is difficult to coordinate and often leads to gap mis-discharge or refused to discharge. To prevent the mis-discharge and refused to discharge. Accurately determine the gap distance is the key to the insulation coordination, the best method is to draw the volt-second characteristic curve, but the curve plotting workload is too multifarious. Therefore, it is proposed to use the normal probability distribution, of lightning impact discharge and power frequency discharge data are analyzed, and the gap distance selection method, the probability of gap mis-discharge and refused to discharge are reduced, the ability of transformer neutral point insulation protection and the power supply reliability are improved. The method is applied to the discharge test of metal oxide surge arrester parallel protective gap device. The method is proved to be accurate and effective.

关 键 词：变压器中性点 正态分布 间隙距离 工频放电电压 雷电冲击放电电压 

分 类 号：TM41[电气工程—电器]