Patent ID: 9231479
Filing Date: 2016-01-05
CPC Classification: H02M

Claim Text:
1. A power supply device, comprising: a rectifier circuit that rectifies an alternating current power supply voltage; a first semiconductor switching device for controlling an input current waveform of the rectifier circuit to a sinusoidal wave; a smoothing capacitor to which an output voltage of the rectifier circuit is applied; a step-up chopper that steps up a voltage across the smoothing capacitor; and an inverter that converts a direct current output voltage of the step-up chopper into an alternating current output voltage and supplies the alternating current output voltage to a load, the step-up chopper including an inductor and a diode mutually connected in series to a positive side direct current bus between the smoothing capacitor and inverter and a second semiconductor switching device connected between a connection point of the inductor and diode and a negative side direct current bus, and the power supply device further comprising an instantaneous voltage drop compensation function whereby an 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 the alternating current power supply voltage and an output voltage of the inverter is maintained at a constant value, wherein a plurality of MOSFETs with a breakdown voltage lower than a breakdown voltage of the first semiconductor switching device are connected in series between a connection point of the smoothing capacitor and inductor and a connection point of the diode and inverter; wherein