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This paper focus on passivity and passive control for a cascade nonlinear system consisting of two switched systems. The asymptotic stability criterion for the cascade system is developed without requiring passivity of subsystem in the whole state interval. Passivity and stabilisation of the closed-loop system are achieved by co-designing an output feedback control law and a state-dependent switching signal if the full output information is measurable. While the output information of the first switched system are not available, the sampled integral stabilisation (SIS) technique which only adopts the output information and common energy function of the second one, is exploited to achieve passive control of two switched systems connected in a cascade way. Then, a particular case of cascade system where only one passive switched system exists is stabilised via SIS technique. Finally, the validity of the developed results is demonstrated via a plane articulation arm example. [ABSTRACT FROM AUTHOR]

This paper investigates the problem of the input-to-state practical stability for switched affine systems with time-varying delay and essentially bounded exogenous disturbance. The presence of affine terms makes switched systems have multiple switched equilibria and brings further difficulties in the stability analysis, control synthesis and avoiding Zeno behaviours compared with the non-affine switched systems. To overcome these difficulties, first, a convex combination approach is employed to acquire a set of attainable equilibria limited by the system matrix, the delay term matrix, and affine terms. Second, a mode-dependent event-triggered mechanism with sampled-data information is established, which not only ignores Zeno behaviour but also effectively reduces network resource waste. An input-to-state practical stability criterion is proposed for the closed-loop system by converting the event-triggered control system into a time-delay system and introducing a less conservative time-dependent Lyapunov–Krasovskii functional. Moreover, a sampled-data switching law and a set of executable controllers are also co-designed. Finally, an application example of the flyback DC–DC converter demonstrates the efficiency of the proposed result. [ABSTRACT FROM AUTHOR]

This paper considers the output-feedback fault-tolerant tracking control problem for a class of uncertain nonlinear switched systems with nonlinear faults and strict-feedback form, where the faults which are nonaffine occur on the actuator. As a kind of specialised function approximating tool, fuzzy logic systems (FLSs), are employed to approximate the unknown smooth nonlinear functions. A switched fuzzy observer is designed to address the problem of unmeasurable states, filtered signals are used to address algebraic loop problem and the average dwell time (ADT) method is further utilised to prove the stability of the resulting closed-loop systems under a type of slowly switching signals. Based on the backstepping recursive design technique and Lyapunov function method, an adaptive fuzzy output-feedback control scheme is developed. The developed control method can ensure all the signals are semi-globally uniformly ultimately bounded (SGUUB) and the system output tracks the reference signal tightly even if unknown fault occurs. A simulation carried on an example demonstrates the validity of the obtained control scheme. [ABSTRACT FROM AUTHOR]