Patent ID: 8212506

Claim:
An AC motor driving circuit for driving a first AC motor from an AC power supply and a DC power supply, which is configured to feed and absorb electric power, through a voltage-type inverter, the AC motor driving circuit comprising: a first rectifier circuit configured to perform power conversion between the AC power supply and the first AC motor, the first rectifier circuit comprising a filter circuit, and first switches, the filter circuit being connected to the AC power supply at an input of the first rectifier circuit, a first terminal of each of the first switches being bridge-connected to an output of the filter circuit in an upper or lower arm of the first rectifier circuit, a second terminal of each of the first switches being connected to an output terminal of the respective upper or lower arm of the first rectifier circuit, the respective output terminal being connected to the first AC motor through the voltage-type inverter; and a second rectifier circuit configured to perform power conversion between the AC power supply and the DC power supply, the second rectifier circuit comprising the filter circuit in common with the first rectifier circuit, second switches and a series circuit, the series circuit including a reactor and the DC power supply, a first terminal of each of the second switches being connected to a junction between the output of the filter circuit and a corresponding one of the first switches in the first rectifier circuit, and a second terminal of each of the second switches being connected to a first terminal of the series circuit including the reactor and the DC power supply, and a second terminal of the series circuit being connected to one of the output terminals of the first rectifier circuit, wherein each switch of the first switches and the second switches is a bidirectional switch or a unidirectional switch, and the series circuit is configured such that the AC motor driving circuit performs both power conversion to the AC motor and charging of the DC power supply.