POWER SUPPLY DEVICE, AND METHOD FOR CONTROLLING SAME

A power supply device is disclosed. The power supply device comprises: a first switch element for selectively providing an AC power source to an actuation device; a second switch element for selectively providing the AC power source to the first switch element; a detection circuit for confirming whether or not the first switch element is in a full turn-on state, by comparing an input power source and an output power source of the first switch element; a sensor for sensing the size of the AC power source; and a controller for selectively controlling the operation of the second switch element on the basis of the sensed size of the AC power source and the confirmed full turn-on state.