一种改进的广义扩展状态观测器在双三相永磁同步电机电流谐波补偿中的应用

Dual three-phase permanent magnet synchronous machine (DTP-PMSM) suffers from the disadvantage of easily occurring large stator current harmonics under inverter nonlinearity, nonsinusoidal back-electromotive force, and external disturbances. To deal with the problem, an improved generalized extended state observer (IGESO) for current harmonic suppression is proposed in this article. First, the relationship between the observation of low-frequency and high-frequency periodic disturbances in conventional disturbance observers is explored. Second, a notch filter is used to optimize the conventional generalized extended state observer (GESO) structure to avoid interference in observing two different frequency disturbances. Then, a novel observer poles design principle is proposed, which can control the suppression frequency range and attenuation of periodic disturbances respectively. Besides, the performance compared with other strategies and the stability analysis of IGESO in the discrete-time domain are presented. The parameter range for system stability is also provided. Finally, the proposed method is evaluated on a laboratory DTP-PMSM platform.