| 摘要 |
PURPOSE:To remove an error of a motor application voltage of an insensitive zone of a PWM control signal by correcting the command value of the voltage in response to the phase difference between a primary current and a secondary current. CONSTITUTION:First calculating means 1 calculates a torque command Tc responsive to the amplitude of a load from a voltage command Vc and a secondary current command I2. A PWM circuit 4 outputs an actual command voltage from the command Tc and the command I2, to an induction motor 5. Second calculating means 2 calculates a phase difference theta between an exciting current I0 and a secondary current command I2. The difference theta is input as a motor application voltage correction amount multiplied by a predetermined constant value K by correcting means 3 to the first calculating means. Thus, an error of the motor application voltage of an insensitive zone of the PWM control signal is removed. |
