| 摘要 |
A power supply device includes a first semiconductor switching device for controlling an alternating input current waveform, a smoothing capacitor to which a rectified voltage is applied, and an inverter that converts the rectified voltage into alternating current via a step-up chopper. The step-up chopper includes an inductor and a diode connected between the smoothing capacitor and inverter, and a second semiconductor switching device connected to the inductor and diode. The power supply device further includes an instantaneous voltage drop compensation function whereby the energy of the smoothing capacitor is supplied by an operation of the step-up chopper to the inverter when there is an instantaneous voltage drop in an alternating current power supply voltage. MOSFETs with a breakdown voltage lower than that of the first semiconductor switching device are connected between terminals of the step-up chopper, thus further reducing loss in comparison with when a bypass diode is used. |
