Model reference FTC for LPV systems using virtual actuators and set-membership fault estimation

In this paper, a model reference fault tolerant control (FTC) strategy based on a reconfiguration of the reference model, with the addition of a virtual actuator block, is presented for linear parameter varying (LPV) systems. The advantage of the proposed FTC method is that the control system is reconfigured in such a way that the nominal controller is used without the need of retuning it. Moreover, the presence of saturations is taken into account through their incorporation in the reference model, and the introduction of additional varying parameters, such that the system exhibits some graceful performance degradation when the system could not achieve the desired state because of the actuator limits. The design of the control scheme is based on linear matrix inequalities (LMIs) and polytopic LPV techniques. In order to implement the proposed active FTC strategy, a fault estimation is required. In this paper, the fault estimation is formulated as a parameter estimation problem, which is solved using a set-membership approach. An aeronautical application is used to assess the performance of the proposed approach. Copyright (c) 2014 John Wiley & Sons, Ltd.