| 摘要 |
PURPOSE:To prevent an inverter from becoming an overcurrent of an overexcitation at deceleration time or from becoming an insufficient starting torque at acceleration time by correcting a delay of an output voltage command reflected for a PWM signal. CONSTITUTION:A memory cell 10 outputs waiting time data indicating time corresponding to one carrier period of a PWM signal in response to an output frequency command from an output frequency deciding circuit 4. A waiting time data selector 11 outputs as waiting time data the data from the cell 10 only when a PWM controller is switched from a normal operation to a decelerating or accelerating operation and waiting time data indicating no waiting time at operating time except that. A voltage correcting data selector 14 selectively outputs as voltage correction data from the cell 13 at decelerating or accelerating time and voltage correction data indicating a correction amount 0 at normal operation time. A waiting time setter 12 and a voltage command adder/ subtractor 15 output an output frequency command and an output voltage command. |
