Based on the linear parameter-varying (LPV) adaptive observer, the robust fault diagnosis for a class of LPV systems with external disturbances is studied. Since the flight control system (FCS) is nonlinear and time-varying, the LPV technique is used for FCS. And then the adaptive fault estimation algorithm based on the LPV adaptive observer is proposed to estimate the fault. To minimize the effect of disturbances on the fault estimation, the H~ robust performance index is introduced to design the LPV adaptive fault diagnosis observer and the fault estimation algorithm. The result shows that the method has good estimation performance and is robust to external disturbances. The design method is presented in terms of linear matrix inequalities (LMIs). Finally, a helicopter LPV FCS model with the actuator fault is used to illustrate the effectiveness of the proposed method.
The fault diagnosis and accommodation strategy for a class of linear parameter-varying (LPV) systems were investigated. A fast adaptive fault estimation (FAFE) algorithm for LPV systems module, based on an adaptive observer, proposed to enhance the performance of fault estimation including rapidity and accuracy. Then, the obtained fault estimate was used to construct the fault tolerant control (FTC) law. The design method was formulated as a convex linear matrix inequalities (LMIs) optimization problem. Once the faults are estimated, the fault tolerant controller is implemented as a dynamic output feedback controller. This controller can compensate for the effect of the faults by stabilizing the closed-loop systems. Finally, a helicopter model in a vertical flight with actuator fault was used to the effectiveness of the proposed approach.