Observer-based fault estimation for a class of discrete-time switched affine systems: An application to the DC-DC converter

Abstract

This paper studies the observer-based fault estimation for a class of discrete-time switched affine systems. A new class of fault estimator with an affine term is first established based on the state observer approach, and a target solution problem of the augmented error system is established under the H∞ performance scheme. The min-type Lyapunov function and its associated switching function are used to obtain the stability condition of the augmented error system in terms of Lyapunov-Metzler inequality. The idea of minimizing the volume of the ellipsoid is adopted containing the set of attraction in order to obtain an attraction set as small as possible. Through solving an optimization problem, the stability of augmented error system can be ensured, and the corresponding fault estimator design is realized in the form of linear matrix inequalities. Finally, a practical application of three level DC-DC multicellular converter is illustrated to verify the effectiveness and practicability of the developed observer-based fault estimation approach.