CAJ | 학술논문

结合某换流站的500 kV站用电变压器进线开关3次误动作实例,介绍了事故的概况,叙述了事故原因的查找过程:检查回路、测试绝缘、更换操作箱插件等方法均未发现异常;通过数字示波器成功地监测到第3次开关跳闸时,各跳闸回路的电压、电流波形,分析波形和涌流抑制器的动作特性后,确定3次事故是由于220 V直流系统接地引起的变压器涌流抑制器开入回路误动作而导致开关误跳闸.针对查找出的原因,从提高装置的抗干扰和改进外部设计回路2个方面采取了相应措施,其效果良好.
결합모환류참적500 kV참용전변압기진선개관3차오동작실례,개소료사고적개황,서술료사고원인적사조과정:검사회로、측시절연、경환조작상삽건등방법균미발현이상;통과수자시파기성공지감측도제3차개관도갑시,각도갑회로적전압、전류파형,분석파형화용류억제기적동작특성후,학정3차사고시유우220 V직류계통접지인기적변압기용류억제기개입회로오동작이도치개관오도갑.침대사조출적원인,종제고장치적항간우화개진외부설계회로2개방면채취료상응조시,기효과량호.
The improper trips of the transformer inlet feeder breaker in a 500 kV converter station are described and the causes are discussed. No abnormality was found during circuit check, insulation test and operating box module replacement. The current and voltage waveforms during the third trip were recorded by the digital oscilloscope and analyzed combined with the operating characteristics of the surge suppressor. The conclusion is that,the improper trips were caused by the binary input circuit malfunction of surge suppressor during the grounding fault of 220 V DC system. Countermeasures are taken in two aspects: enhancement of device anti-interference capability and improvement of external circuit design.