| 摘要 |
PROBLEM TO BE SOLVED: To suppress demagnetization of an electric motor.SOLUTION: When a fan 53 is rotated by an external wind, an electric motor 52 connected to the fan 53 generates power to output a regenerative current Ir1 to a motor inverter 4. Waveform shaping means 12 performs PWM control such that motor inverter control means 10 drives the motor inverter 4 to generate a shaped regenerative current Ir2 having a current waveform shaped to a sinusoidal wave on the basis of a frequency and a current value detected by regeneration detection means 11. Furthermore, it is determined whether or not compressor inverter control means 20 is in the process of performing constraint energization on a compressor 51, and if the compressor 51 is not in operation, PWM control on a compressor inverter 3 is started to perform constraint energization on the compressor 51. The regenerative current output from the electric motor 52 is then consumed as power for the constraint energization. |
