Robust Deadbeat Predictive control for SynRel Motor Based on Hyperbolic Tangent Observer

The deadbeat predictive control has a high dependency on the parameters of the plant's model. This issue has been subsided in recent studies by utilizing the disturbance observers (DOs) to improve the robustness of the deadbeat control against the parameter variations. This paper presents a novel hyperbolic tangent observer (HTO) to improve the performance of the deadbeat control of the synchronous reluctance (SynRel) motor. The HTO has a characteristic similar to the linear observer (LO) for the small errors, and it acts the same as the sliding mode observer (SMO) when the error takes a high value. Therefore, the proposed HTO-based deadbeat control takes the good characteristics of both LO and SMO and, it roots out their drawbacks, such as the chattering problem of SMO and the poor performance of LO in nonlinear systems. In the simulation, the effect of uncertain parameters of the SynRel motor on the performance of the proposed HTO-based deadbeat control has been studied. The results showed that the proposed control system has good robustness against the parameter variations even in severe circumstances.