Dynamic-High-Gain-Based Decentralized Optimal Fault-Tolerant Control for a Class of Interconnected Nonlinear Systems

In this article, a dynamic high-gain-based decentralized optimal fault-tolerant control (FTC) strategy for a class of strong interconnected systems with unknown actuator faults is proposed. The interactions considered are bounded by some functions that depend on all subsystems' states. A two-layer control framework is presented for each subsystem to steer its tracking error asymptotically to zero. In the upper layer, an error optimizer is designed to generate optimal error trajectory based on a local objective function that converges to zero. In the lower layer, with the aid of an auxiliary system, a trajectory-tracking fault-tolerant controller is given to adaptively accommodate the effects of parameteric uncertainties and actuator faults, where an adaptive high-gain approach is adopted to address the unknown strong interactions. In comparison with existing results, the proposed algorithm relaxes the requirement of output trajectory derivatives, and asymptotic tracking is accomplished. Application results obtained using an electrical power system case demonstrate the validity of the proposed algorithm.