Abstract: Distributed capacitance has an adverse effect on the DC ground fault search,resulting in false alarms or insufficient detection sensitivity.It may also cause protection malfunctions during the grounding fault search .This paper analyzes the impact of distributed capacitance on DC grounding fault search from the perspective of DC system architecture,fault type and grounding fault search principle,and distinguishes large distributed capacitance branches from the perspective of phase comparison and characteristic frequency to achieve anti-distributed capacitance during grounding fault search.

Key words: DC grounding fault, distributed capacitance, characteristic frequency, phase comparison