| 摘要 |
PROBLEM TO BE SOLVED: To detect motor current accurately in synchronous PWM control.SOLUTION: An inverter 20 for supplying power to a motor 10 is subjected to switching control by a PWM signal. A PWM signal generation unit 16 generates a PWM signal synchronized with a voltage command, based on a voltage command from a voltage command generation unit 13, and the number of pulses from a pulse generation unit 18. A sampler 24 samples and holds a current detection value of a motor current, detected by a current sensor 22 and supplied to a motor, at an angular interval determined by dividing 60° by an integer of 8 or more with reference to the phase angle 0° of the motor current. The current detection value thus sampled and held is subjected to three-phase/dq axis conversion, before being subjected to moving average in a moving average unit 28. |
