| 摘要 |
PURPOSE:To stably operate a motor even at a decelerating time by detecting an accelerating or decelerating current component, subtracting the component by the main circuit of the motor, and feeding back the load current component of the motor thus obtained. CONSTITUTION:A primary delay differentiating circuit 10 and a gain multiplier 11 are added to the conventional circuit having a motor controlling circuit 1, a field voltage coefficient unit 2, a motor torque transmitter 4, and a drooping circuit 4. A motor load current is detected or calculted, a contant is multiplied by the obtained load current, and the product thus obtained is fed back to a rotating speed command value, and the speed of the motor is controlled. Since the drooping compensation can be performed without affect of the accelerating or decelerating current even when the drooping constant is different at every motor or an entirely different accelerating or decelerating current flows though a plurality of motors in this manner, it can suppress the variation of the tension occurred at the rolled material or strip steel plate. |
