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Active Disturbance Rejection Control for Permanent-magnet Synchronous Motor Drives
Fast dynamic response, precise tracking performance, and strong robustness to disturbance are usually needed for high-performance field-oriented control (FOC) of permanent-magnet synchronous motors (PMSMs). Moreover, electromechanical sensors are commonly used to obtain accurate rotor position information for the FOC of PMSMs. The use of these sensors not only increased the cost but also reduced the reliability of the PMSM drive system. To overcome these drawbacks, the development of rotor position sensorless FOC schemes for PMSMs is desired. In this dissertation, based on the active disturbance rejection control (ADRC) technique, three control schemes, i.e., an adaptive sliding-mode current control (SMCC), an adaptive sliding-mode speed control (SMSC), and a robust rotor position sensorless control were developed for PMSMs. In the adaptive SMCC scheme, an extended state observer (ESO) was designed to estimate in real time the PMSM parameter variations, which were treated as the internal disturbance of the PMSM drive system; the control law of the SMCC was then adapted by compensating the estimated internal disturbance. The adaptive SMSC scheme was designed in a way similar to the adaptive SMCC scheme. The core of the sensorless control scheme is a novel enhanced linear ADRC (ELADRC) algorithm consisting of two linear ESOs (LESOs) and a proportional current controller. One LESO was designed to estimate the back electromotive force, which was treated as the external disturbance. The other LESO was designed to estimate the internal disturbances, i.e., parameter and current regulation quality variations. The estimated total disturbance was used as a feedforward compensation term in the current control loops to improve the current regulation quality of the PMSM drive, which further improved the rotor position estimation performance. The proposed three control schemes were validated by experimental studies on two laboratory PMSM drive testbeds. The experimental results showed that the proposed ADRC-based adaptive SMCC and SMSC schemes had a faster dynamic response, more precise current and speed tracking performance, and stronger robustness to disturbances than the existing control schemes. Moreover, the proposed ELADRC-based sensorless FOC scheme had better dynamic performance and was more robust to PMSM parameter variations than the existing sensorless FOC schemes.
Qu, Lizhi, "Active Disturbance Rejection Control for Permanent-magnet Synchronous Motor Drives" (2019). ETD collection for University of Nebraska - Lincoln. AAI27667156.