Research on Power Closed-Loop Torque Control Strategy of PMSM in HEV Application

The flux linkage of permanent magnet synchronous machines(PMSM) is sensitive to ambient temperature and stator currents. The relationship among power, torque and flux of SPMSM and IPMSM with i_d=0 control method was studied. A flux estimation strategy based on power closed-loop was proposed. This strategy could lead to a more accurate torque control. The results of simulations and experiments show that the estimated flux linkage in the proposed strategy can follow the real flux-linkage fast and accurately. This strategy shows a good dynamic performance and anti-interference performance in hybrid electric vehicle (HEV) application.