| 摘要 |
PURPOSE:To suppress a harmonic current and to reduce the capacity of an AC/DC converter by PWM-controlling the converter based on a current reference signal having the same phase as the secondary voltage phase of a wound-rotor type induction motor in proportion to a deviation in amplitudes between a speed detection signal of the motor and a speed reference signal. CONSTITUTION:A current reference signal is proportional in amplitude to a deviation signal between a speed detection signal of a motor 2 and a speed reference signal, and has the same phase as the secondary voltage phase of the motor. A motor secondary current detected by a secondary current detector 11 and a current reference signal are applied to a secondary current controller 12, its deviation signal becomes an output signal, and a PWM controller 13 is controlled by the signal. If the voltage of a commutation capacitor 20 becomes higher than the voltage of a power capacitor 20A, the capacitor 20A is charged. The DC voltage of the capacitor 20A is applied to a DC/AC converter 22 and converted to an AC. The converted AC is regenerated to an AC power source 1 through a reactor 21 and a transformer 25. |
