Air-conditioning apparatus

An air-conditioning apparatus comprising:

• a compressor to compress a refrigerant;
• a motor to drive the compressor;
• an inverter to apply a desired voltage to the motor;
• an inverter controller to control the inverter;
• and
• a bus voltage detector to detect a bus voltage that is a power source of the inverter,
• the inverter controller including:
• a dormant refrigerant detector to detect a dormant state of refrigerant in the compressor;
• a high-frequency AC voltage generator to output a high-frequency AC voltage command when the motor is not undergoing a compression operation which has a frequency that is higher than a range of operating frequencies when the motor is undergoing the compression operation to three phases of a coil of the motor on the basis of an output of the dormant refrigerant detector and an amplitude and a phase input from outside of the high-frequency AC voltage generator;
• and
• a pulse width modulation (PWM) signal generator to cause the inverter to generate a high-frequency AC voltage by generating and outputting a PWM signal to the inverter on the basis of the high-frequency AC voltage command output by the high-frequency AC voltage generator and an output of the bus voltage detector,
• wherein upon an output of the PWM signal from the PWM signal generator to the inverter, the refrigerant in the compressor is heated by iron loss and copper loss in the motor.