摘要
某220kV降压变压器在低压侧差动保护区内故障时,两套不同制动原理的纵联差动保护出现了不同的动作行为。通过对保护装置故障录波数据的离线分析计算,发现了相间故障时,低压侧并联补偿电容器的自由振荡谐波电流对变压器纵联差动保护的影响原因。分析了故障期间并联补偿电容器的谐波电流产生原因及幅频特性,并提出了对差动保护原理的改进建议。
When a failure occurs in the low voltage side differential protection zone of a 220 kV step-down transformer,two sets of longitudinal differential protection act differently on different breaking principles. According to offline analyses and calculations with MATLAB software upon protection device recorded wave data,it has been found why free oscillation of the harmonic current of the low voltage side parallel compensation capacitor impacts the transformer longitudinal differential protection when inter-phase fault occurs.Also,an analysis is made of the cause of generation of harmonic current and its amplitude frequency characteristics of the parallel compensation capacitor during the fault.Suggestions for improvement of the differential protection principles are also made.
出处
《电力系统自动化》
EI
CSCD
北大核心
2015年第8期159-163,共5页
Automation of Electric Power Systems
关键词
变压器保护
差动保护
故障录波
谐波电流
故障分析
transformer protection
differential protection
fault recording
harmonic current
fault analysis
