POWER CONVERTER AND PROTECTION METHOD FOR SHORT CIRCUIT TO GROUND ON DIRECT CURRENT SIDE THEREOF

A power converter includes a power conversion circuit, a relay, and a controller. The power conversion circuit can be configured to implement conversion from a direct current to an alternating current. The relay can be configured to implement on-grid and off-grid switching. The controller can be configured to control switch-on/off of switches in the power conversion circuit and the relay. When a positive direct current bus has a short circuit to ground, the controller switches off a relay of a corresponding phase when any phase of grid voltage is negative. When a negative direct current bus has a short circuit to ground, the controller switches off a relay of a corresponding phase when any phase of grid voltage is positive.