Active Disturbance Rejection Control Strategy for PMSM Speed Control Based on Improved High-order Extended State Observer

In order to solve the problem of disturbance rejection and noise suppression of extended state observer (ESO) and high order ESO (HESO), an improved HESO (IHESO) is proposed. First, the ESO and HESO are introduced and their limitations are analyzed. Subsequently, a low-pass filter (LPF) and a new controllable parameter k are introduced into the IHESO, and its internal structure is reconstructed to ensure the reliability of the structure. The introduction of the LPF enhances the ability of noise suppression of IHESO. The introduction of the parameter, k, improves the degree of freedom of parameter adjustment, thus helping to separately adjust the disturbance rejection and noise suppression abilities of IHESO. Lastly, the active disturbance rejection control (ADRC) system based on IHESO is verified on an experimental platform. The experimental results show that the IHESO is 5.26% and 31.58% higher than ESO and HESO, respectively, in terms of noise suppression, and 18.29% and 27.79% higher than ESO and HESO, respectively, in terms of disturbance rejection.