HEAT PUMP DEVICE, AIR-CONDITIONER, AND REFRIGERATOR

摘要

A heat pump that has a compressor equipped with a motor for which sensorless vector control is possible even at a low rotation speed or under a low load is obtained while the cost thereof is suppressed. This heat pump device is equipped with a refrigerant compressor (14) that is driven by a motor (21), an inverter unit (12) for applying a voltage to the motor (21), current sensors (26a, 26b) for detecting a motor current, and an inverter control unit (13) for outputting a drive signal to the inverter unit (12). The inverter control unit (13) is equipped with a voltage command computation part (25) and a drive signal generation section (23). The drive signal generation section (23) is equipped with an amplitude/phase determination part (33) that determines a refrigerant compression amount required of the compressor (14) in accordance with signals from the current sensors (26a, 26b) so as to determine an amplitude and a phase in order for the drive signal generation section (23) to generate a drive signal. When the motor (21) is operating at a low rotation speed or under a low load, the voltage command computation part (25) corrects the signals from the current sensors (26a, 26b) in accordance with the rotation speed or the load.