Optimal Fault-Tolerant Control for Dynamic Systems with Distributed Fault Parameter Uncertainty Domains

Abstract

This paper presents an optimal fault-tolerant control (FTC) method for dynamic systems with distributed fault parameter uncertainty. According to the distributed characteristic of the fault parameter uncertainty domain and insufficient fault information, identify the controller parameter feasible domain on each distributed fault parameter uncertainty sub-domain, respectively. The intersection of all controller parameter feasible domains is the feasible domain of fault-tolerant controller parameters. The optimal fault-tolerant controller with an optimal performance index is obtained from the feasible domain of fault-tolerant controller parameters. Update the optimal fault-tolerant controller according to the increase in fault information. When the fault diagnosis procedure stops providing more useful fault information, the optimal fault-tolerant controller ceases its updates. After fully identifying the fault, an active fault-tolerant controller is designed based on the fault parameter values. An optimal fault-tolerant control algorithm based on quadratic stability control is introduced for distributed fault parameter uncertainty domains. Firstly, the currently distributed fault parameter uncertainty domain is determined based on insufficient fault information. Then, we design the quadratic stability controllers for each distributed uncertainty sub-domain of fault parameters to get the controller parameter feasible domain. The optimal fault-tolerant controller with an optimal performance index is obtained from the feasible domain of fault-tolerant controller parameters. Once the fault is identified, the optimal fault-tolerant control converges to the linear quadratic regulator (LQR) control. The simulation results confirm that the proposed method and algorithm are feasible and effective.