Prescribed‐Time Sliding Mode Control for Improving Speed Tracking Convergence Time of Induction Motor

ABSTRACT The problem of model uncertainty and the variation of modeling parameters of the motor is one of the key issues facing induction machine drives. Hence, the control strategy of this class of motors should cope with uncertainties and finally deliver accurate control results. However, on the other hand, convergence time is another issue in control strategies of induction machines, so that with the variations of the reference speed, the controller should track the reference signal and make the motor speed reach it quickly. This paper proposes the prescribed sliding mode control (PSMC) technique. Precisely, based on the Lyapunov theory, stability of the system will be proved in a specified period of time, so that motor speed reaches the reference speed within a specific time. This way, we can ensure that the controller convergence time can be predetermined and achieved before designing this controller. In addition, the control loop's resistance to changes in parameters or model uncertainties will also be resolved. In order to examine the performance of the proposed method, a series of practical experiments were conducted on an induction motor in the laboratory, and the results obtained confirm the effective performance of this method in reducing convergence time and resistance to uncertainties. The results of practical experiments show that the proposed method has reduced the convergence time to 0.1 s and the steady‐state error to 0.9 rpm, which is a significant improvement over conventional methods such as ASMC and PI. Also, the robustness of the proposed method against parameter variations of up to ±10% has been confirmed with an error of less than 2.5 rpm, indicating its effective performance under conditions of model uncertainty.