Adaptive Critic for Event-Triggered Unknown Nonlinear Optimal Tracking Design With Wastewater Treatment Applications

• Published in: IEEE transaction on neural networks and learning systems Vol. 34; no. 9; pp. 6276 - 6288
• Main Authors: Wang, Ding, Hu, Lingzhi, Zhao, Mingming, Qiao, Junfei
• Format: Journal Article
• Language: English
• Published: United States IEEE 01.09.2023; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Approximation algorithms; Closed loops; Control algorithms; Control methods; Control systems; Control theory; Dissolved oxygen; Dynamic programming; Event-triggered mechanism; Feedback control; Heuristic algorithms; iterative adaptive critic; Iterative methods; Mathematical models; Neural networks; nonaffine nonlinear systems; Nonlinear dynamical systems; Nonlinear systems; optimal tracking control; Tracking control; Trajectory; Trajectory tracking; Wastewater treatment; Wastewater treatment plants; Water treatment
• ISSN: 2162-237X; 2162-2388; 2162-2388
• DOI: 10.1109/TNNLS.2021.3135405

In this article, an event-based near-optimal tracking control algorithm is developed for a class of nonaffine systems. First, in order to gain the tracking control strategy, the costate function is established through the iterative dual heuristic dynamic programming (DHP) algorithm. Then, the event-based control method is employed to improve the utilization efficiency of resources and ensure that the closed-loop system has an excellent control performance. Meanwhile, the input-to-state stability (ISS) is proven for the event-based tracking plant. In addition, three kinds of neural networks are used in the event-based DHP algorithm, which aims to identify the nonaffine nonlinear system, estimate the costate function, and approximate the tracking control law. Finally, a numerical experimental simulation is conducted to verify the effectiveness of the proposed scheme. Moreover, in order to further validate the feasibility, the algorithm is applied to the wastewater treatment plant to effectively control the concentrations of dissolved oxygen and nitrate nitrogen.