Minimal Switch Step Tracking Control of Switched Systems with Application to Induction Motor Control
For control engineers designing switched systems with costly switching, this work provides a method to minimize switching frequency while maintaining tracking performance.
The paper addresses step tracking control for switched systems using only switching inputs, aiming to minimize the number of switchings. The proposed method is applied to induction motor control, achieving superior performance in reducing mode switches compared to direct torque control.
The problem of step tracking control with a switching input and without any continuous-valued inputs is considered. The control objective is to reduce the number of switchings to a minimal value. This approach finds interesting applications when switching comprises costs and should be avoided. To solve the problem, a state dependent switching strategy should be designed and the resulting closed loop is indeed a hybrid system. Therefore, first we investigate the conditions on a hybrid system for being the desired solution. Then, we propose a method for designing the switching strategy such that the closed loop as a hybrid system solves the problem. The proposed method is applied to the induction motor control problem which results in relatively simple and efficient control algorithm. Comparison with the direct torque control for induction motors show that our method has a superior performance in reducing the number of mode switches.