Heat pump apparatus, air conditioner, and refrigerator

An air conditioner comprising

• a heat pump apparatus further comprising:
• a compression mechanism to compress a refrigerant;
• a motor to drive the compression mechanism;
• an inverter to apply a voltage to the motor;
• and
• an inverter control circuitry to generate a drive signal for driving the inverter, based on a carrier signal,
• wherein the inverter control circuitry
• periodically changes a carrier frequency of the carrier signal in a heating operation mode in which the refrigerant is heated, and
• generates the drive signal such that a period of time during which a voltage represented as a real vector is applied to the motor is kept constant regardless of the changed carrier frequency.

A refrigerator comprising

• a heat pump apparatus further comprising:
• a compression mechanism to compress a refrigerant;
• a motor to drive the compression mechanism;
• an inverter to apply a voltage to the motor;
• and
• an inverter control circuitry to generate a drive signal for driving the inverter, based on a carrier signal,
• wherein the inverter control circuitry
• periodically changes a carrier frequency of the carrier signal in a heating operation mode in which the refrigerant is heated, and
• generates the drive signal such that a period of time during which a voltage represented as a real vector is applied to the motor is kept constant regardless of the changed carrier frequency.