A Dynamic Proportional-Integral Observer-Based Nonlinear Fault-Tolerant Controller Design for Nonlinear System With Partially Unknown Dynamic

Abstract

For the nonlinear system with partially unknown dynamic, the problems of fault estimation and fault-tolerant control are considered. A novel adaptive observer is designed to reconstruct the system state, process fault, sensor fault, and the measurement disturbance, simultaneously. The designed observer can be treated as a dynamic proportional-integral observer, where both the output information and the derivative of the output are used, while the output derivative can be unmeasurable. Utilizing the estimation information obtained by the designed observer, a nonlinear fault-tolerant control technique is proposed to stabilize the system. At the end of this article, three examples are listed to verify the proposed method.