BATTERY CHARGER

In a battery charger, the rectifier includes rectifying elements provided for respective three phases. The rectifier supplies, for the respective phases, currents for rectifying three-phase AC voltages so as to charge a battery. A voltage detector detects whether or not the battery is charged. Switching units are provided for the respective rectifying elements, and rectify the AC voltages to charge the battery in the off-state. Switch controllers output gate signals in accordance with a timing of zero-cross detection upon receiving a detection signal indicating that all the gate signals for turning on and off the respective switching units for the respective phases are supplied in the order of the phases. On the other hand, upon receiving a detection signal indicating that all the gate signals for the respective phases are not supplied in the order of the phases, the switch controllers output gate signals to the corresponding switching units in synchronization with the detection signal so as to enter the shorting state.