Abstract: DC loop network fault is one of the common forms of insulation faults in DC power systems. This article analyzes the causes, types and hazards of ring network faults. Focusing on the equivalent circuit of the DC power system, the voltage manifestations of various ring network faults are expounded from the perspective of circuit structure, and the essence of loop network fault hazards is revealed. Finally, according to the physical phenomenon of the loop network fault, the specific operation method of the loop network fault is given.

Key words: DC power system, DC loop network fault, equivalent circuit