| 摘要 |
PROBLEM TO BE SOLVED: To calculate accurate power consumption without increasing costs and upsizing devices.SOLUTION: A motor drive steps down an input voltage Vdc that is input to a chopper circuit ch by the chopper circuit ch including a switching element Sw1 and a reactor Ldc, converts a DC power outputted from the chopper circuit ch to an AC power for output to a motor M by driving an inverter INV with 120°conduction, and clamps a surge current generated in the commutation of the inverter INV to the input voltage Vdc by a diode D1 connected in inverse parallel with the chopper circuit ch. In the motor drive, power consumption P at motor driving is calculated from the input voltage Vdc, switching duty of the switching element Sw1 of the chopper circuit ch, a reactor current Idc, a motor winding reactance Lm, and a motor speed N. |
