| 摘要 |
PURPOSE:To accurately control the rotating speed of an induction motor by controlling the rotating speed without using detectors such as speed detector or the like merely by detecting the primary current of the motor. CONSTITUTION:A torque current component Iq is detected by a current component detector 9. This component is compared with a torque command T* at an addition point 10, and a slip angle frequency omegas is regulated in response to the frequency control signal Aomega in response to a deviation. The presumed value (n) of the speed is calculated by an equation (where omega1* is a frequency command, K is a proportional constant) at the point 15. A speed deviation amplifier 7 outputs a torque command T* in response to the deviation between the speed command n* and the value (n), the torque is controlled proportionally to the torque command T* as described above to control the speed. |
