Optimal Solution for Model Predictive Current Control of Surface Mounted Permanent Magnet Synchronous Motor Based on Trigonometrical Substitution

This paper proposes an analytic solution of the optimal voltage vector for model predictive current control, in order to achieve the excellent dynamic and steady-state current performance of surface mounted permanent magnet synchronous motor (SMPMSM). The voltage vector in the stationary reference frame is firstly defined by its phase and amplitude. Through coordinate transformation and the predictive model of SMPMSM drive system, the cost function related with the voltage vector is established. Then it can be transformed into two different forms which are only relevant to the phase or amplitude of voltage vector by trigonometrical substitution. Next, the analytic solution of optimal voltage vector with continuous phase and amplitude is easy to derive by the two different forms of cost function with extremum. The optimal voltage vector is finally synthesized by three-vector method, and the experiments under various operating conditions are implemented to verify the effectiveness of the proposed method.