Talking about the Inspection Method of Grounding Fault in DC System in Substation

After the grounding fault occurs in the DC system in the substation, which ground should be detected first, it can be determined by performing the sub-combination test of the circuit, and it can be performed while avoiding the peak of power consumption. The order of split and merge can refer to the following steps:

Emergency lighting → Signal circuit → Charging circuit → Outdoor closing circuit → Carrier standby power for indoor closing circuit → 6 to 10 kV control circuit → Main control circuit above 35 kV → DC bus → Battery.

The above order is not definite, and the actual operation can be flexibly controlled according to the specific circumstances. In the case of split and joint time, the dispatcher's consent must be obtained first if it involves the equipment within the jurisdiction of the dispatcher.

Once the ground loop is found, the fuses of the loop are further divided and combined, or the disconnection method is used to further narrow the fault range until the fault point is found.