Rotary electric machine driving device

A rotary electric machine driving device that drives and controls an alternating-current rotary electric machine, the rotary electric machine driving device comprising:

• an inverter that is electrically interposed between a direct-current power supply and the rotary electric machine, and converts electric power between a direct current and an alternating current;
• a smoothing capacitor that is electrically interposed between the direct-current power supply and the inverter, and is connected between a positive pole and a negative pole on a direct-current side of the inverter;
• an inverter control unit that controls switching of a switching element of the inverter according to a predetermined switching frequency;
• and
• an inductance control unit that switches a direct-current side inductance between a positive pole of the direct-current power supply and a positive pole of the smoothing capacitor, according to the switching frequency, between a predefined standard inductance and a high inductance that is higher than the standard inductance, wherein in a frequency characteristic of a direct-current side voltage gain obtained by dividing a system voltage that is a voltage on the direct-current side of the inverter by a system current that is a current on the direct-current side of the inverter, a first frequency is a frequency at which a value of the direct-current side voltage gain corresponding to the standard inductance is equal to a value of the direct-current side voltage gain corresponding to the high inductance,
• in a frequency characteristic of the direct-current side current gain obtained by dividing a power supply current that is a current flowing through the direct-current power supply by the system current, a second frequency is a frequency at which a value of the direct-current side current gain corresponding to the standard inductance is equal to a value of the direct-current side current gain corresponding to the high inductance, and
• the inductance control unit switches the direct-current side inductance to the standard inductance when the switching frequency is lower than a frequency of a switching point set in a frequency range between the first frequency and the second frequency and to the high inductance when the switching frequency is higher than the frequency of the switching point.