Fault-Tolerant Control design using a virtual sensor for LPV systems

In this paper, a Fault Tolerant Control (FTC) strategy using a virtual sensor for Linear Parameter Varying (LPV) systems is proposed. The main idea of this FTC method is to reconfigure the control loop such such that the nominal controller could be still used without need of retuning it. That is, the plant with the sensor fault is modified adding the virtual sensor block that masks this fault and allows the controller to see the same plant as before the fault. This virtual sensor is designed using polytopic LPV techniques and Linear Matrix Inequalities (LMIs). The LPV state feedback controller is designed for quadratic H₂/H_∞ performance using a polytopic representation of the system that leads to solve a finite number of algebraic LMIs. To assess the performance of the proposed approach a two degree of freedom helicopter is used.