POWER SUPPLY DEVICE AND SWITCH CONTROL METHOD THEREFOR

摘要

This power supply device is provided with: an AC electric path extending from an input terminal to an output terminal; a current sensor that detects current flowing through the AC electric path; a conversion unit that is connected to the AC electric path and that can bidirectionally convert power, and a storage battery that is connected to the AC electric path via the conversion unit; an AC switch that is provided between the input terminal and the connecting point of the conversion unit to the AC electric path and that includes a parallel body of a relay contact and a semiconductor switch; and a control unit that controls the conversion unit and the AC switch. The control unit executes a current-carrying mode or a storage-battery discharge mode, and at the initial start of the current-carrying mode and when overcurrent is detected by the current sensor during the current-carrying mode, the control unit closes only the relay contact while keeping the semiconductor switch open.