| 摘要 |
PURPOSE:To control slip frequency properly at all times by controlling primary frequency in response to the phase difference of exciting current command pattern signals formed in a control circuit and the magnetic flux detecting signals of the motor. CONSTITUTION:The output currents of a PWM inverter 3 is controlled so as to follow a current command pattern from an adder 15. The current command pattern is generated by a circuit consisting of a speed command circuit 5, a speed detector 6, a speed deviation amplifier 7, an adder 8, an oscillator 9, an exciting current command circuit 10, multipliers 11-14 and the adder 15. Slip frequency is controlled at proper value by controlling primary frequency in response to phase difference between the current command pattern and the magnetic flux detecting signals of the motor 4. |
