AC-DC withstand voltage partial discharge test circuit

An AC-DC withstand voltage partial discharge test circuit comprises an AC circuit, a DC circuit and an AC-DC coupling circuit, wherein the AC circuit processes an AC power supply and then outputs an AC voltage; the DC circuit processes the AC power supply and then outputs a DC voltage; and the output AC voltage and the output DC voltage are respectively connected with the two ends of the AC-DC coupling circuit, so as to provide an AC voltage, a DC voltage or a AC-DC superposed voltage for a to-be-tested component. Aiming at a support capacitor of a DC power transmission key component, the invention provides the AC-DC withstand voltage partial discharge test circuit for simulating the AC-DC voltage superposition condition borne by a test sample during actual operation of the component, theAC-DC withstand voltage partial discharge test circuit is used for a product test with AC-DC high-voltage partial discharge test requirements, and can be used for AC, DC and AC-DC combined tests respectively. The AC-DC withstand voltage partial discharge test circuit has the advantages of high pertinence, low manufacturing cost, no partial discharge of the circuit and the like, and can effectivelydetect the insulation defect of the supporting capacitor component.