Active Disturbance Rejection Speed Control With Double-Stage-ESO Considering Aperiodic and Periodic Disturbances for PMSM Drives

This article proposes an optimal active disturbance rejection control (ADRC) strategy for permanent-magnet synchronous motors (PMSMs), to improve the speed performance under periodic and aperiodic disturbances. First, the speed harmonics and the weakness of conventional linear ADRC are analyzed, and the disturbance rejection ability is found to be degraded due to the limited bandwidth of the extended state observer (ESO). To enhance the disturbance rejection ability, a novel double-stage-ESO (2S-ESO) is proposed, which integrates the advantages of both cascaded-ESO and the quasi-resonant controller. In the proposed control scheme, 2S-ESO works through two stages where the cascaded structure is adopted to realize an increase in the numerator order of disturbance estimation error transfer function, and the estimation accuracy is improved. Meanwhile, a composite ESO embedded with the quasi-resonant controller is designed in the second stage, where accurate estimation and attenuation of the periodic disturbance can be achieved. Compared with the existing ADRC technique, both the dynamic response and steady-state accuracy with the proposed method are greatly improved, and strong robustness is also maintained. Experiments are carried out to validate the effectiveness of the proposed scheme.