Abstract: A welding power supply device includes an inverter for converting DC power into AC power outputted to a welding load, and a voltage circuit for superimposing a restriking voltage on an output to the welding load when the polarity of output current of the inverter switches. The voltage circuit includes a restriking capacitor charged with the re-striking voltage, a charging circuit to charge the capacitor with the restriking voltage, and a discharging circuit to discharge the voltage in the capacitor. The charging circuit includes a DC power supply and a booster to boost DC voltage from the DC power supply. The charging circuit charges the restriking capacitor in first and second states. In the first state, the DC voltage from the DC power supply is directly applied to the re-striking capacitor. In the second state, DC voltage boosted by the booster is applied to the restriking capacitor.

Abstract: A welding power supply device includes an inverter for converting DC power into AC power outputted to a welding load, and a voltage circuit for superimposing a restriking voltage on an output to the welding load when the polarity of output current of the inverter switches. The voltage circuit includes a restriking capacitor charged with the restriking voltage, a charging circuit to charge the capacitor with the restriking voltage, and a discharging circuit to discharge the voltage in the capacitor. The charging circuit includes a DC power supply and a booster to boost DC voltage from the DC power supply. The charging circuit charges the restriking capacitor in first and second states. In the first state, the DC voltage from the DC power supply is directly applied to the restriking capacitor. In the second state, DC voltage boosted by the booster is applied to the restriking capacitor.