A Robust Sequential MPC With a Chattering Free Adaptive Sliding-Mode Speed Controller

Model predictive torque control has gained much attention due to its fast response to torque changes. Nevertheless, finding the optimum weighting factor is a complex and time-consuming process. Sequential model predictive control (SMPC) with a hierarchical structure eliminates the need for a weighting factor. In conventional SMPC, a PI speed controller has been utilized to generate torque reference, which leads to poor dynamics and is sensitive to motor parameters. Moreover, it is affected significantly by load changes. A sliding-mode controller (SMC) is robust to uncertainties and disturbances. However, it suffers from the chattering phenomena. To mitigate this problem, this study proposes a new reaching law based on the adaptive controller and sigmoid function. The adaptive sliding-mode speed controller-based SMPC (ASMC-SMPC) results in better robustness and chattering reduction that proved with a comparison between PI-SMPC, SMC-SMPC, and ASMC-SMPC through relevant simulations in MATLAB Simulink.