Model-Free Predictive Current and Speed Control for Modular Drive of a Non-Sinusoidal, Six-Phase Permanent Magnet Synchronous Motor with Double-Winding Stator based on Extended State Observers

Multi-phase PMSMs are considered to increase the reliability of the high-power propulsion systems. This paper presents a model-free current and speed predictive control (MFPCSC) method based on ultra-local model for an asymmetric six-phase PMSM with non-sinusoidal back-EMFs. The proposed MFPCSC method is robust to model uncertainties and disturbances. To maximize the reliability, each phase has two windings and each winding has an open-end connection, in which the drive topology is fully modular. Due to the modular structure, there are limitations in the modeling and control of the motor, in which the conventional methods in dq reference frames cannot be employed. Also, due to torque ripples caused from non-sinusoidal back-EMFs, the current shaping method has been used in the six-axis stationary reference frame. To make the control method robust to changes in motor model parameters and reduce sensitivity to current controllers, six extended state observers (ESOs) based on an ultra-local model are used to estimate current and total disturbances. The superiority of the proposed control method over conventional control methods based on hysteresis, PI and proportional-resonant (PR) current regulators is verified by simulation in Simulink, and some experimental test results are presented to validate the proposed theories.