The speed fluctuation constraints (SFC) of permanent magnet synchronous motors (PMSM) are widely considered in practical applications. However, the multiple disturbances in the PMSM systems lead to extremely complicated SFC control problem. In this paper, a composite barrier function-based sliding mode control (BFSMC) approach is developed to deal with this problem. First, a disturbance observer is constructed to estimate the lumped disturbances, including cogging torque, parameter uncertainties and unknown load torque, which widely exist in the PMSM systems. Then, a novel BFSMC is designed, in which the switching gain is determined by the barrier function to achieve the goal of SFC when facing the above disturbances. Finally, a composite controller is formed by introducing disturbance estimation. The proposed method obtains a smaller flexible switching gain, which not only achieves the target of SFC, but also substantially alleviates the chattering phenomenon. The stability analysis of the closed-loop control system is presented. Both simulations and experimental tests are applied to demonstrate the efficiency of the proposed method.

In this paper, the speed regulation control problem for permanent magnet synchronous motor (PMSM) under the single-loop control structure is investigated. Specifically, certain issues, such as the risks of over-current and multi-source disturbances, can increase the likelihood of damage to the system circuitry and lead to unsatisfactory speed regulation performance. To tackle these issues, a current-constrained continuous nonsingular terminal sliding mode control (CNTSMC) approach via the control barrier function (CBF) technology is proposed. First, a nonlinear finite-time extended state observer is constructed to estimate the unmatched disturbances in PMSM systems. Subsequently, a new composite CBF-based CNTSMC method incorporating the disturbance estimation is designed, such that the undesirable influence of multi-source disturbances on the control performance can be effectively attenuated, while guaranteeing strict current constraints. Finally, the stability analysis of the closed-loop control system is presented. Comparative experimental results demonstrate that the proposed method achieves better speed regulation and critical current constraint performance even in the presence of unmatched disturbances.

This article investigates the robust control problem for speed regulation of networked permanent magnet synchronous motor subject to the limited communication bandwidth. To handle this, a new sampled-data disturbance rejection control method is developed via a well-designed discrete-time dynamic event-triggered mechanism (DETM). First, a predictor-based generalized proportional integral observer is introduced to estimate the lumped disturbances, when only the sampled-data output is available. Then, a composite proportional feedback controller is formed by fully utilizing disturbance estimation. The composite controller updates only when the designed discrete-time DETM is violated, resulting in remarkable communication and computation resource savings while maintaining the desirable disturbance rejection ability. The designed DETM can be applied to digital computers easily due to the discrete-time detection. Simulations and experiments are carried out to validate the feasibility and effectiveness of the proposed control scheme.

The single-loop control structure of permanent magnet synchronous motor (PMSM) is widely considered in practical applications. However, certain issues such as overcurrent risks and multisource disturbances may result in unsatisfactory speed regulation performance and increase the risk of damage to the system circuitry. In this article, a current-constrained continuous nonsingular terminal sliding mode control (CNTSMC) approach is proposed to address these problems. First, two finite-time disturbance observers (FTDOs) are designed to estimate both matched and mismatched disturbances in the PMSM systems. Then, a composite CNTSMC method incorporating the disturbance estimation is designed to improve the anti-disturbance ability of PMSM systems. To realize overcurrent protection, a novel switching idea is introduced based on the composite CNTSMC method, which is implemented only when the current reaches the constraint boundary. Finally, the stability analysis of the closed-loop control system is presented, and the proposed method is demonstrated to be effective through experimental tests.

In high-precision permanent magnet synchronous motor (PMSM) servo applications, it is essential to achieve both rapid and accurate positioning control while constraining the speed and current under multi-source disturbances. To achieve this objective, this paper proposes a composite control barrier function (CBF)-based enhanced terminal sliding mode control (TSMC) strategy. First, two finite-time generalized proportional integral observers (FTGPIOs) are designed for matched and unmatched disturbance estimation in PMSM servo systems. By capturing disturbances and their high-order derivatives, FTGPIOs deliver superior estimation accuracy, with finite-time convergence ensuring fast error reduction. Then, a disturbance-compensated finite-time TSMC approach is constructed for finite-time position tracking stability. Meanwhile, a disturbance-integrated robust CBF technique is designed for real-time optimization, effectively limiting speed and current deviations during positioning. Finally, the effectiveness of the proposed method is validated via rigorous stability analysis as well as comprehensive simulation and experimental comparisons.

This brief introduces a fully distributed fault-tolerant control scheme based on a dual-channel dynamic event-triggered mechanism (DETM) for multi-agent systems (MASs) affected by both external disturbances and actuator faults, aiming to achieve leader-following bipartite consensus. To reconstruct unknown system states, external disturbances, and actuator faults, a series of observers is developed utilizing only local output measurements. Based on these estimates, a fully distributed fault-tolerant control law is formulated to ensure leader-following bipartite consensus, while simultaneously enhancing robustness against disturbances and resilience to faults. To alleviate communication burdens, dual-channel DETMs are implemented on both the sensor-to-observer (S-O) and observer-to-controller (O-C) channels, where internal dynamic variables are employed to adaptively adjust the triggering thresholds. The efficacy of the proposed method is validated via simulations studies on robotic manipulator systems.