Electric leakage detection circuit structure of DC power supply output bus

The invention discloses an electric leakage detection circuit structure of a direct-current power supply output bus, and belongs to the electrical field. The circuit structure comprises a bridge circuit, a subtraction circuit, an isolation uploading circuit, a comparison circuit and a reference level circuit, the bridge circuit is used for sampling impedance of a direct-current power supply output positive bus or negative bus to the ground, and the subtraction circuit is used for adjusting a sampling level. The isolation uploading circuit is used for carrying out isolation uploading on the adjusted sampling level to prevent short circuit caused by the fact that the front end and the rear end of sampling uploading share the reference ground, and the comparison circuit is used for generating a low-level protection signal when the insulation resistance is detected to be lower than the reference level, so that the function of alarming when electric leakage of a direct-current power supply output bus is detected i