Robust H ∞ Control for the Nonlinear Cascade Systems with Passive and Nonpassive Subsystems

In this paper, H ∞ control for the uncertain switched nonlinear cascade systems with passive and nonpassive subsystems is investigated. Based on the average dwell time method, for any given passivity rate, average dwell time, and disturbance attenuation level, the feedback controllers of the subsystems by predetermined constants are designed to solve the exponential stability and L 2 -gain problems of H ∞ control for switched nonlinear cascade systems. Two examples are provided to demonstrate the effectiveness of the proposed design method.

Integrated Fault Detection and Fault Tolerant Control for Switched Systems with Asynchronous Switching

The problem of integrated fault detection and fault tolerant control for switched systems with asynchronous switching is focused on in this paper. Based on the switched model, the inherent asynchronous switching is taken into consideration. The asynchronous switching means that the switching of filters/controllers will always lag behind the switching of modes, which will degrade the performance of the closed-loop system. The Lyapunov functional method and mode-dependent average dwell time method are combined for the analysis of the finite-time stability of the switched system. The properties of each subsystem are taken into consideration, which are less conservative. To achieve optimal performance, the filters and controllers are designed simultaneously. The parameters of filters and controllers are given in the form of linear matrix inequalities. In the end, the numerical example is given to illustrate the effectiveness of the proposed method.

Finite-time boundedness and stabilization of switched nonlinear systems using auxiliary matrices and average dwell time method

This paper focuses on the finite-time boundedness of switched nonlinear systems based on the Finsler’s lemma, auxiliary matrices, and average dwell time method. The analysis is provided for a switched system with Lipschitz nonlinearities and in the presence of external disturbances. Moreover, a switching controller is designed based on linear matrix inequalities (LMIs), to make the closed-loop system finite-time bounded. Presented theorems in this paper are more general and have less conservatism than the existing methods due to using the auxiliary matrices that make the Lyapunov matrix separate from the system matrix in the resulting LMIs. Moreover, in all theorems, the average dwell time of the switching system has been evaluated. Three examples are given to illustrate the effectiveness of the proposed method and to show that it is less conservative compared with existing methods.