| 摘要 |
PURPOSE:To improve response property by controlling the output frequency of an inverter in response to the quantity of variation of the magnetic flux of the motor while altering the direction of variation of the output frequency of the inverter on the basis of phase difference between the voltage of the motor and the currents of the motor. CONSTITUTION:The inverter 1 is controlled by means of a control circuit 100. The control circuit 100 is formed by a voltage detector 5 detecting the output voltage of the inverter, voltage deviation amplifiers 6, 7 amplifying deviation between output voltage proportional signals and output from the detector 5, a magnetic flux detector 8, a phase difference detector 9, a polarity inverting appliance 10, a subtractor 11, an oscillator 12 outputting the signals of frequency proportional to the output of the subtractor 11, a current command circuit 13, a comparator 15 and a gate circuit 16 for giving a GTO a gate on the basis of PWM signals from the comparator 15. |
