Structured H∞/H_ LPV filters for fault diagnosis: Some new results

In this paper, a method is presented to design robust fault detection and isolation filters for Linear Parameter Varying (LPV) systems modeled in a Linear Fractional Representation (LFR) fashion. It consists in designing an optimal FDI filter that minimizes the influence of unknown inputs on the residuals, in the H∞-norm sense and simultaneously maximizes fault sensitivity performance, in the H_-index sense. The design problem is formulated so that all free parameters are optimized via Linear Matrix Inequality techniques. Computational aspects are discussed and it is shown that the proposed solution is structurally well-defined. An illustrative example demonstrates the potential of the proposed method.