Fault-tolerant control of systems with convex polytopic linear parameter varying model uncertainty using virtual-sensor-based controller reconfiguration

In this paper, a novel robust sensor fault tolerant control strategy for systems with linear parameter varying (LPV) uncertainty model description is proposed. The strategy combines a robust fault detection and identification (FDI) unit based on an invariant-set approach with controller reconfiguration based on the use of a virtual sensor. The robust FDI unit employs a bank of observers that can detect faulty and healthy situations based on the separation of relevant sets, whose computation takes into account system disturbances and model uncertainty. The closed-loop system is reconfigured by means of a virtual sensor which is adapted to the fault situation detected by the FDI unit. The FDI and virtual sensor modules are designed using polytopic LPV techniques and bilinear matrix inequalities. The resulting robust fault tolerant control scheme is guaranteed to preserve boundedness of the closed-loop system trajectories under a wide range of sensor fault scenarios. The performance of the proposed scheme is illustrated by a simulation example.