Research on Modified Active Disturbance Rejection Control for PMSM Speed Regulation System

Active disturbance rejection control (ADRC) has broad application prospects in permanent magnet synchronous motors (PMSMs) due to its advantages of being independent of the controlled object model, excellent adaptability, and strong anti-disturbance performance. When tuning the bandwidth (ω0) of ADRC, the anti-disturbance performance of the control system is improved with the increase in bandwidth, yet the noise suppression performance of the system is degraded. This trade-off restricts the selection of bandwidth and further impairs the dynamic performance of the system. To address this issue, this paper proposes a modified ADRC (MADRC) strategy based on a modified extended state observer (MESO). The MESO expands the differential terms of disturbances into new state variables. By conducting multi-layer observation of disturbances and their differential signals, the anti-disturbance performance of the system is enhanced while its noise suppression performance is maintained. Frequency-domain analysis of the MESO and the conventional extended state observer (ESO) demonstrates that the MESO achieves a stronger anti-disturbance performance in the low-frequency band, with its noise suppression performance remaining unchanged in the high-frequency band. Finally, experimental comparisons between the conventional ADRC and the proposed MADRC are carried out on a PMSM platform to verify the superiority of the proposed strategy.