Model-Free Predictive Current Control of DTP-PMSM Based on Ultra-Local Model Considering Back EMF Harmonics
Shuang Wang, Huiyan Fan, Jianfei Zhao
Abstract
To achieve robust control against parameter variations for dual three-phase permanent magnet synchronous motor (DTP-PMSM), an improved model-free predictive current control (MFPCC) based on the ultra-local model is proposed in this article. First, the parameter mismatch on conventional predictive control is analyzed, and it is worth noting that the back-electromotive force (back EMF) harmonics have a huge impact on the current harmonics. Therefore, unlike the conventional schemes, the ultra-local model considering back EMF harmonics is employed to replace the fundamental and harmonic subspace current prediction models. Then, to meet the fast response and reduce chattering, a slide mode observer (SMO) based on improved reaching law is designed to estimate the disturbance and currents. Twelve virtual voltage vectors are synthesized for further suppressing currents in harmonic subspace. Finally, both simulation and experimental results show that the proposed method has the preferable robust performance and can reduce the phase current harmonics under parameter mismatches.