摘要
针对一起500kV线路远跳保护误动跳闸事故,分析了三相组式变压器励磁回路,确定了当保护装置内部电压变换器一次侧中性线开路时,因一次绕组励磁电流中的三次谐波分量无法在3个磁路相互独立的绕组中构成通路,从而使一次绕组励磁电流中不含三次谐波分量,导致激磁电势畸变,在二次绕组中产生含有较高三次谐波的尖顶波,造成远跳保护装置感受的电压升高而误动。通过试验仿真验证,并提出了预防措施。
This paper analyzes a mal-operation of a 500 kV line remote tripping protection caused by neutral line open.The reasons of mal-operation are analyzed by simulation and locale experiment.When neutral line of three phase configuration voltage transformer opens,gateway for third harmonics of excitation breaks in three windings,whose magnetic circuits are mutual independence.Excitation current does not contain third harmonics,peaked waveform which contains third harmonics come into being in secondary windings and distorted electromotive force results in a mal-operation.Finally,it is verified by simulation test and the preventive measures are presented as well.
出处
《水电能源科学》
北大核心
2011年第3期159-161,共3页
Water Resources and Power
关键词
远跳保护
中性线
误动
三次谐波
磁路
remote tripping protection
neutral line
mal-operation
third harmonics
magnetic circuits
