Model predictive control (MPC) has been widely applied in the field of motor drives due to the advantages of simple structure and satisfactory dynamic performance. In conventional MPC method for open winding permanent magnet synchronous motor (OW-PMSM) where only one voltage vector (VV) acts to the corresponding dual inverters in one control period, the voltage error between the ideal VV and the actual one exists. There is no doubt that increasing the number of VVs in each control period will improve the control performance of OW-PMSM. However, the increase in the number of VVs will lead to higher switching frequency, which means that the loss caused by the switching devices will increase and thus reducing the operation efficiency of OW-PMSM. Combined with the purpose of improving the control performance of OW-PMSM and balancing the effect of switching frequency, a novel hybrid MPC considering dead-zone effect (HMPC-DZE) method is proposed in this paper. Firstly, conventional MPC method is introduced. On this basis, HMPC-DZE method is put forward. In HMPC-DZE method, only one optimal VV acts to inverter1 (INV1) in one control period while dead-zone effect is considered. For inverter2 (INV2), duty ratio control is adopted. As a result, the acting time of dead-zone corresponding to INV1 is variable and the action time of non-zero VV corresponding to INV2 is no more equal to the whole control period. Finally, the simulation results conducted on Matlab/Simulink demonstrate that the proposed method can effectively reduce the current total harmonic distortion (THD) and the ripple of zero-sequence current (ZSC) compared to conventional MPC method.

Model predictive control (MPC);open winding permanent magnet synchronous motor (OW-PMSM);dead-zone;duty ratio control