In this article, a novel adaptive super-twisting nonlinear Fractional-order PID sliding mode control (ASTNLFOPIDSMC) strategy using extended state observer (ESO) for the speed operation of permanent magnet synchronous motor (PMSM) is proposed. Firstly, this paper proposes a novel nonlinear Fractional-order PID (NLFOPID) sliding surface with nonlinear proportion term, nonlinear integral term and nonlinear differential term. Secondly, the novel NLFOPID switching manifold and an adaptive supertwisting reaching law (ASTRL) are applied to obtain excellent control performance in the sliding mode phase and the reaching phase, respectively. The novel ASTNLFOPIDSMC strategy is constructed by the ASTRL and the NLFOPID sliding surface. Due to the utilization of NLFOPID switching manifold, the characteristics of fast convergence, good robustness and small steady state error can be ensured in the sliding mode phase. Due to the utilization of ASTRL, the chattering phenomenon can be weakened, and the characteristics of high accuracy and strong robustness can be obtained in the reaching phase. Further, an ESO is designed to achieve dynamic feedback compensation for external disturbance. Furthermore, Lyapunov stability theorem and Fractional calculus are used to prove the stability of the system. Finally, comparison results under different controllers demonstrate that the proposed control strategy not only achieves good stability and dynamic properties, but also is robust to external disturbance.

This article presents the event-triggered control for T-S fuzzy networked systems with transmission delay. An integral-based model is proposed for designing a new event triggered scheme, which relies on the mean of the system state and the last triggered state. To handle the asynchronous premises of fuzzy system and fuzzy controller, a novel triggering condition is added into the event-triggered mechanism. Then the closed loop T-S fuzzy event-triggered control system is established as a distributed delay system. With the help of the Legendre polynomials and their properties, the co-design conditions of triggering parameters and controller gains are given in linear matrix inequalities to ensure the asymptotic stability of the resulting closed-loop system. At last, an experiment via a practical wireless network is implemented to illustrate the effectiveness of the proposed approach.

In this paper, a novel fixed-time nonsingular fast terminal sliding mode control incorporating with an adaptive disturbance observer is proposed for second-order uncertain nonlinear systems to achieve fast stabilization and robust control. Based on the theory of fixed-time convergence, a novel fixed-time stable system is first investigated. Using this system, a novel fixed-time nonsingular fast terminal sliding mode controller is developed, which can achieve system stabilization within bounded convergence time regardless of initial states and provide nonsingularity and fast convergence. Moreover, an adaptive disturbance observer is designed to improve the control performance and compensate for uncertain disturbances. The fixed-time stability of the sliding surface and the system states under the proposed composite control scheme are demonstrated by the Lyapunov stability theory. Both theoretical analysis and simulation results are presented to verify the feasibility and superiority of the proposed method.

In this research, based on the ultra-local model, a novel compound model-free control strategy with an intelligent Proportional-Integral and super-twisting Sliding Mode Control (MFiPISTSMC) strategy for permanent magnet synchronous motor (PMSM) drives is proposed. Firstly, an intelligent Proportional-Integral (iPI) control strategy is designed for motor speed regulation. Secondly, a super-twisting Sliding Mode Control (STSMC) strategy is constructed based on the ultra-local model of PMSM. At the same time, the unknown term of the ultra-local model of PMSM is estimated by a Linear Extended State Observer (LESO). The stability of the compound MFiPISTSMC strategy is proved by the Lyapunov stability theorem. As a result of the compound MFiPISTSMC strategy integrating the STSMC strategy, the iPI control strategy and the LESO is proposed to have excellent performance. Finally, the static characteristic, dynamic characteristic and robustness of the novel compound MFiPISTSMC strategy are verified by simulation and experimental results.