New model based predictive current control strategy for doubly salient permanent magnet synchronous machines

摘要

The doubly salient permanentmagnet synchronous machine (DSPMSM) has got extensive attention during the past couple of years for its demonstrated advantages of brushless rotor with strong mechanical robustness, reasonable high torque/power densities, good thermal dissipation ability, etc. However, due to salient shapes of stator/rotor, the DSPMSM sacrifices its torque and flux ripples in comparison to other rotor-inserted PMSMs. Recently, the conventional switching-table-based model based predictive torque control (MPTC) has received increasing attention due to its merits of quick dynamic response, strong robustness and simple control structure. However, the theoretical analysis of MPTC algorithm for DSPMSM is very complex, and difficult for practical implementation. This paper presents one improved strategy to reduce the torque ripple of the DSPMSM drive system with the help of model based predictive current control (MPCC), which is a new algorithm combining direct torque control (DTC) and MPTC strategies. Different from the traditional MPTC strategy requires complete decoupling calculation, the new MPCC method only needs the current predictive value with a simple control structure. Meanwhile, in order to reduce the torque and flux ripples simultaneously, it further presents three new forms of cost functions based d-q axis error currents. Comprehensive simulations verify relevant theoretical analysis.