发电机定子接地故障处理和分析

Analysis and Handling of A Generator Stator Ground Fault

针对某电厂600 MW机组在试运行过程中的定子接地保护的动作事故,根据现场的故障录波波形和数据,以及对定子接地时的电压变化特点进行分析,并通过升压试验,发现故障是因为励磁机侧A相一根下层线棒引水管渗漏而造成的A相定子经高阻接地故障。通过对整个事故进行处理分析,并对以后的调试及故障处理提出一些经验和建议。

Stator ground fault protectionaction occurred during commissioning of a 600 MW generator in a certain power plant.According to the fault wave graphics and data,the paper analyzes generator voltage variation characteristic when the stator winding was grounded,and found that the main cause was the water pipe leakage at exciter end,which leads to the phase A stator grounded by high impedance through generator start-up test.The fault handling measures and the experience lessons were advised.