Cascaded Model Predictive Control for the Ferrite-Assisted Synchronous Reluctance Motor with Asymmetric Rotor Structure

The ferrite-assisted synchronous reluctance motor (FA-SynRM) with asymmetric rotor structure can highly improve motor performance by making its magnetic and reluctance torques reach their maximum values near or at the same current phase angles. Considering the asymmetric rotor structure and the flux shift, a new design of maximum torque per ampere (MTPA) control strategy and a cascaded model predictive control (MPC) method are needed. In this paper, the MTPA control strategy and cascaded MPC method are designed for the FA-SynRM with asymmetric rotor structure. The construction of current-loop model predictive controller is deduced in detail. A new design of MTPA control strategy is derived to make full use of both components of its torque. By simulations under different load and speed conditions, it is demonstrated that the proposed MTPA control strategy and cascaded MPC method for FA-SynRM has high accuracy and stability in complex conditions.