A Computationally Efficient Model Predictive Control Method for Dual Three-Phase PMSM of Electric Vehicle With Fixed Switching Frequency

Aiming at the problems of large harmonic current, unfixed switching frequency and heavy calculation burden in the model predictive current control (MPCC) methods of dual three-phase permanent magnet synchronous motor (DT-PMSM). This article presents a computationally efficient MPCC method with a fixed switching frequency. Firstly, the virtual voltage vectors (V
³
s) are synthesized by two large vectors and two medium-small vectors. The V
³
s effectively reduce the harmonic currents, and the goal of the synthetic V
³
is that the harmonic current in the x-y subspace is zero. Therefore, the weighting factor of the harmonic term is eliminated in the cost function. Secondly, an optimal voltage vector selection method is designed to reduce the candidate voltage vectors in the control set and relieves the calculation burden. In addition, to further reduce ripple current and torque ripple, the duty cycle modulation method is introduced to calculate the dwell time of the V
³
. The zero vector is inserted in the middle and both sides of the V
³
s to achieve the purpose of fixing the switching frequency. Finally, the effectiveness of the proposed method is verified by experiments.