Robust speed control of IM with torque feedforward control

The authors present a robust speed control of an induction motor (IM) using a load torque observer and feedforward control. The speed response characteristics using a conventional PI (proportional plus integral) controller are affected by variations of system parameters. With the proposed system, the load torque disturbance and the effects of motor and mechanical parameter variations can be removed. The entire control processing was performed by the software of a digital signal processor within a reasonable period, and experimental results showed the robustness of the control system against the disturbance torque and the variation of motor and mechanical parameters