High Precision Model Predictive Current Control of Dual Three-Phase Permanent Magnet Synchronous Motor

In this paper, a current discrete model of dual three-phase permanent magnet synchronous motor (DTPPMSM) is derived to solve the problem of large current prediction error, which is caused by the traditional current discrete model in model predictive control when the motor operates under low carrier ratio condition. The proposed current discrete model considers the change of rotor position in a control period, which improves the accuracy of current prediction. Based on the derived current discrete model, a model predictive current control strategy suitable for low carrier ratio condition of DTP-PMSM is proposed. The candidate vector set is composed of 24 virtual voltage vectors and zero vectors, which reduces the current harmonics. The comparison results show that the proposed strategy has smaller dq-axis current and electromagnetic torque tracking errors than the traditional strategy under low carrier ratio condition, which improves the steady-state performance of the motor.