Cascade PI-continuous second-order sliding mode control for induction motor

This paper presents the cascaded PI-continuous second order sliding mode control for induction motor in the presence of operational constraints. The inner-loop Sliding Mode Control (SMC) is designed to control the current dynamics of the motor while the outer-loop control is the PI control of speed. The main advantages of the proposed method are that the PI control provides reference to inner-loop SMC with constraints according to the system requirements in terms of maximum current and speed limits. Moreover the inner-loop dynamics of the motor being more non-linear, SMC design has more importance in terms of robustness and disturbance rejection capability. The proposed cascade PI with SMC is chattering-free control action with fixed-time convergence. The performance of the developed controller is validated and compared by carrying out real-time experimental studies. Experimental results demonstrate remarkable robust tracking performance of the controller in terms of transient response speed and steady-state accuracy.