变电站直流系统寄生回路的排查方法探讨

Abnormal phenomenon discrimination method of DC parasitic loop for substation

通过对变电站直流系统电压异常进行测试,分析了存在直流寄生回路的原因。对比分析常用的排查方法及技术方案,结果表明,采用直流钳形表的方法测电源正负极差流,采用试拉自动化系统直流、试拉二次保护直流的措施是有效可靠的。在此基础上,总结出产生直流寄生的主要诱因,主要有器件缺陷、设计缺陷以及管理原因等,对提高本地区电网的运行可靠性有重要意义。

Based on measurement results of the abnormal DC system voltage,the reasons and the countermeasures of the DC parasitic loop are analyzed in this paper.Several investigation methods and technical program are proposed and compared,the discrimination methods include differential current measurement between positive and negative polarity with DC pince instrument,testing break method of DC source for automation system and protection system.After that,the causes of the DC parasitic loop are summarized,for example apparatus defection,design defection,management defection and so on.It holds substantial essentiality in improving the reliability of the operation of regional power grids.