ADP-based online compensation hierarchical sliding-mode control for partially unknown switched nonlinear systems with actuator failures

• Published in: ISA transactions Vol. 155; pp. 69 - 81
• Main Authors: Wang, Tengda, Niu, Ben, Xu, Ning, Zhang, Liang
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.12.2024
• Subjects: Adaptive dynamic programming; Fault tolerant control; Hierarchical sliding mode surface; Identifier-critic network; Neural network; Identifier-critic network; Hierarchical sliding mode surface; Neural network; Adaptive dynamic programming; Fault tolerant control
• ISSN: 0019-0578; 1879-2022; 1879-2022
• DOI: 10.1016/j.isatra.2024.09.011

This article investigates an adaptive dynamic programming-based online compensation hierarchical sliding-mode control problem for a class of partially unknown switched nonlinear systems with actuator failures and uncertain perturbations under an identifier-critic neural networks architecture. Firstly, by introducing a cost function related to hierarchical sliding-mode surfaces for the nominal system, the original control problem is equivalently converted into an optimal control problem. To obtain this optimal control policy, the Hamilton–Jacobi–Bellman equation is solved through an adaptive dynamic programming method. Compared with conventional adaptive dynamic programming methods, the identifier-critic network architecture not only overcomes the limitation on the unknown internal dynamic but also eliminates the approximation error arising from the actor network. The weights in the critic network are tuned via the gradient descent approach and the experience replay technology, such that the persistence of excitation condition can be relaxed. Then, a compensation term containing hierarchical sliding-mode surfaces is used to offset uncertain actuator failures without the fault detection and isolation unit. Based on the Lyapunov stability theory, all states of the closed-loop nonlinear system are stable in the sense of uniformly ultimately boundedness. Finally, numerical and practical examples are given to demonstrate the effectiveness of our presented online compensation control strategy. •An HSS-based online compensation control method is firstly presented for partially unknown switched nonlinear systems with actuator failures and uncertain perturbations.•The designed method considerably reduces the conservativeness arising from the unknown internal dynamics of switched nonlinear systems.•By utilizing the HSS technique, our proposed method has a faster response speed and stronger robustness, and is insensitive to unknown actuator failures.