Model Predictive Torque Control of Five-Phase PMSM by Using Double Virtual Voltage Vectors Based on Geometric Principle

Abstract

The conventional model predictive torque control (MPTC) suffers from the heavy computation burden and the uncertainty of the weighting factor. This article proposed a new MPTC scheme for a five-phase permanent magnet synchronous motor by using double virtual voltage vectors (VVVs), in which no weighting factor is required. The VVVs that can restrain the harmonics work as the candidate vectors. The deadbeat principle is adopted to predict the reference voltage, which can be used to select the optimal VVV directly in avoid of testing all candidate VVVs, and hence, the computation burden is reduced. The geometric principle is applied to select the second voltage vector and calculate the vector duration. The second vector can be a VVV or null vector. Therefore, double VVVs or a VVV and a null vector can be synthesized for the next period. It should be noted that no weighting factor is required because of the introduced geometric principle. Due to the selection of the second voltage vector, the torque and flux ripples are reduced and the steady-state performance is improved. The proposed MPTC has the same fast dynamic response with the conventional MPTC. The experiments are presented to verify the proposed MPTC scheme.