基于改进电桥法的直流系统接地故障检测方法

直流系统的稳定性影响着发电厂和变电站的安全运行,介绍了几种传统的直流系统接地故障检测方法,并分析了每种方法的优缺点。针对传统直流系统接地故障检测方法的不足,提出了一种基于改进电桥法的故障检测方法,通过两次投切检测电阻来检测电桥上的不平衡电流和支路漏电流,计算得出接地电阻并快速找出故障支路,通过对比分析发现改进电桥法的测量准确性更高。

Ground fault detection method for DC system based on improved electric bridge method

The stability of DC system affects the safe operation of power plants and substations.Several traditional DC system grounding fault detection methods were introduced, and the advantages and disadvantages of each method were analyzed.In view of the shortcomings of traditional DC system grounding fault detection methods, a fault detection method based on improved bridge method was proposed.The unbalanced current and branch leakage current on the bridge were detected by switching the detection resistance twice, and the grounding resistance was calculated and the fault branch was quickly found out with the method.The comparative analysis show that the measurement accuracy of the improved bridge method is higher.