摘要
研究了和应涌流造成电流互感器暂态饱和情况下,经电流互感器传变后和应涌流的二次谐波含量与间断角的变化。推导了和应涌流的二次谐波含量计算公式;分析电流互感器暂态饱和后传变工频分量与二次谐波分量的特性,从而计算经电流互感器传变后和应涌流的二次谐波含量,并分析电流互感器暂态饱和对和应涌流间断角的影响。研究表明,相同涌流时间宽度的励磁涌流与和应涌流具有相同的二次谐波含量,和应涌流本身并不是引起差动保护误动的原因;当电流互感器饱和时,其传变高次谐波的能力比传变低次谐波的能力强,即经饱和电流互感器传变的和应涌流,二次谐波含量将升高;经饱和电流互感器传变的和应涌流间断角将减小,并且电流互感器饱和越严重,间断角减小得越多。
Second harmonic proportion and dead- angle of sympathetic inrush transferred by transiently saturated CT（Current Transformer） are investigated. The formula for calculating the second harmonic proportion of sympathetic inrush is derived, the transfer characteristics of saturated CT for each harmonic are analyzed, and the second harmonic proportion of sympathetic inrush transferred by transiently saturated CT is calculated. The influence of CT saturation on dead-angle is studied. The results indicate that, as the second harmonic proportion of sympathetic inrush is similar to that of magnetizing inrush, the sympathetic inrush itself is not the essential cause of differential relay mal-operation; as higher harmonic is transferred more easily by the saturated CT than lower harmonic, the second harmonic proportion of sympathetic inrush at CT secondary side is higher than that at CT primary side; the dead-angle of sympathetic inrush transferred by saturated CT is decreased, and the more saturated CT is, the smaller dead-angle is.
出处
《电力自动化设备》
EI
CSCD
北大核心
2009年第1期83-88,共6页
Electric Power Automation Equipment
基金
supported by the National Natural Science Foundation of China(90610024,50347026,50467002)
Yunnan Science and Technology Project(2003GG10)
Natural Science Foundation of Yunnan Province(2002E0025M,2004E0020M,2005F0005Z)
Youth Foundation of Kunming University of Science and Technology(2006-43)~~
