Robust fault-tolerant control systems design with actuator failures via linear fractional transformations

This paper presents a linear matrix inequality (LMI) approach to solve the robust fault-tolerant control (FTC) problem with actuator failures. According to an equivalent transformation, fault effect factors can be put in linear fractional transformation (LFT) form. Then, based on the information from the fault detection and diagnosis (FDI) mechanism, the fault-tolerant control problem can be solved with a well-recognized design approach in robust control area called gain-scheduling control theory, and a fault-tolerant controller which provided with adaptive function can be developed for satisfactory performance. Also based on the LFT framework, the case of error estimation is considered in this paper with applying mu-theory for guaranteeing the closed-loop system´s stability and performance. The proposed design technique is finally evaluated in the light of a simulation example.