一起直流接线错误引起的环网故障分析

Analysis of A Ring Network Fault Caused by DC Wiring Error

发电厂电缆绝缘老化、施工受损、积水受潮、接线错误等,往往会破坏直流系统的绝缘水平,影响着机组的安全稳定运行。针对某电厂2号机组运行时两组直流绝缘监测装置同时故障报警,但两组直流母线电压均正常的现象,排查出直流系统存在环网故障,对该现象进行了理论分析,总结直流系统环网时的故障规律,为直流系统的可靠运行提出建议。

The insulation level of DC system is often damaged due to aging of power cable insulation,damaged construction,damp accumulation and faulty wiring,which affects the safe and stable operation of units.In the light of the phenomenon that two sets of DC insulation monitoring devices are given an alarm at the same time but both sets of DC bus voltage are normal during the operation of unit 2 of a power plant,it is found that there is a loop network fault in the DC system,and this.phenomenon is theoretically analyzed,the fault rules of DC system loop network are summarized,and some suggestions for reliable operation of DC system are put forward.