摘要
在电缆三相同时发生绝缘故障时,用电桥法定位将产生较大误差。本文通过理论分析导得一校正公式:lcx=(k+1/k-1)lmx-2l/(k-1),其中k为近似完好相与故障相绝缘电阻比,l为电缆的全长,lmx为故障位置的测量值,lcx为lmx的校正值。实验表明,如k>2,经校正的定位误差将小于±1%,其准确度能完全满足工程测量的要求。
If insulation failures exist in all three phase of a cable,the failure point locating error caused by bridge circuit will be large.By means of theoretical analysis,a corrective formula is deduced in this paper:l c x=k+1k-1l m x-2lk-1,where k is the insulation resistance ratio of the approximate normal phase to the fault phase, l is the cable's total length, l m x is the measured value of the failure point location, l c x is the corretive value of l m x .Experiments indicate that if k>2 ,the corrective locating error is less than ±1%,which is accurate enough for engineering application.
出处
《中国电机工程学报》
EI
CSCD
北大核心
1998年第5期361-367,共7页
Proceedings of the CSEE
关键词
电缆
绝缘故障
定位
电桥法
地下电缆
cable\ \ three phase insulation failure\ \ locating\ \ bridge circuit