A novel sliding mode control method for induction motor drives

A sliding mode control method for induction motor drives is presented. Based on the model of the induction motor in the frame rotating synchronously with the stator current vector, the method possess two distinct features: decoupling control of the two components of torque; and insensitivity to motor parameter variations. The control law is represented in inequalities instead of equalities. Therefore, when the motor parameters are changed, the stability of the sliding mode and the feature of independent control will not be destroyed as long as the corresponding inequalities hold valid. That is why the proposed method is very robust. Experimental results show that even when the motor parameters are changed to a large extent, the performance of the control system remains almost unchanged