Patent ID: 8559142

Claim:
A DC power supply insulation fault detection circuit, comprising: at least one leakage current detector located in a circuit of a power supply system to detect leakage current of the circuit; at least one positive voltage transient compensator which includes a first charge/discharge circuit and a first energy storage circuit, the first charge/discharge circuit including a first resistor which has one end connected to a positive terminal of the power supply system and another end coupled with the first energy storage circuit in series, the first energy storage circuit having another end grounded and including a resistor and a first energy storage element coupled in parallel; and at least one negative voltage transient compensator which includes a second charge/discharge circuit and a second energy storage circuit, the second charge/discharge circuit including a second resistor which has one end connected to a negative terminal of the power supply system and another end coupled with the second energy storage circuit in series, the second energy storage circuit having another end grounded and including a resistor and a second energy storage element coupled in parallel, wherein the first charge/discharge circuit of the positive voltage transient compensator is coupled with a first discharge circuit in parallel, the first discharge circuit including a first one-way discharger.