Design of a novel switched fault estimator with adaption law for non-linear switched systems and application to chemical systems

This paper presents a novel approach to concurrently designing an adaptive fault estimator and a persistent dwell-time switching law for switched systems incorporating non-linear Lipschitz terms. The adaptation law is formulated using multiple Lyapunov functions, ensuring accurate estimation of system faults and H∞ performance for the estimation error dynamics. Optimal decision coefficients for non-linear terms are computed to enhance problem feasibility and improve estimator performance. The switching law is tailored to fulfill the weightless H∞ criterion with a physical rationale. Formulated using linear matrix inequalities, the design requirements are easily implementable, enabling common solvers to attain estimator gains. The proposed estimator is applied to a practical chemical system, showcasing effective reduction of disturbance effects on fault estimation error and increased accuracy in estimation. Simulation results corroborate the estimator's performance.