Research On The Filtering And Event-Triggered Control Of Networked Switched Systems

Switched system has always been one of the research hotspots in the field of system and control,because it is capable of modelling practical system with multi-modes or multi-controllers.Among the various types of switched systems,time-dependent switched system(TDSS)and Markov stochastic switched system(or Markov jump system,MJS)have attracted the most attention.In addition,the rapid development of communication and computer technologies makes it a trend using shared communictaion network to exchange information among system components.Networked transmission provides possibility to improve the dynamic performance of a system,but also induces different kinds of defects.Therefore,it is significant but challenging to carry out the research on the analysis and synthesis problems of networked switched systems.Based on the previous work,this dissertation further studies the filtering problems of networked TDSSs and the eventtriggered control problems of networked MJSs,in order to reduce the conservativeness of the existing research results and improve their applicability in practice.The main contents are summarized as follows:The strictly dissipative filtering problem is studied for a class of time-dependent switched nonlinear system(TDSNS)with mixed time delays in a complex network environment including signal quantization,data dropout and random parameter perturbation.To ensure the filtering effect under the influence of network-induced defects,a resilient filter with greater capability of antijamming is designed.A decoupling lemma is proposed to deal with the coupling terms of two different types of uncertainties,the difficulty of filter design caused by considering parametric uncertainty and quantization error in the same structure is thus overcome.An average dwell time(ADT)switching rule is considered for the TDSNS.By constructing a mode-dependent Lyapunov-Krasovskii functional(LKF),sufficient conditions are obtained to ensure the mean-square exponential stability and strict dissipativity of the augmented system,the design method of the resilient filter is then presented.Finally,the effectiveness of the proposed method is verified.The idea of mode-dependent resilient filter proposed in this dissertation makes up for the deficiency of the exsiting research results on the filtering problem of TDSS,and provides a theoretical basis for the following asynchronous filtering issue of TDSNS.The finite-time H? filtering problem for the TDSNS with mixed time delays is studied.A novel asynchronous filter model is established,which considers the mismatch case between filter mode and system mode caused by the factors like transmission delay besides the aforementioned typical network-induced defects.In addition,to reduce the influence of data dropout on the filter performance,a memory compensation scheme is exploited when the data loss occurs in the measurement output.By constructing a piecewise and mode-dependent LKF,combined with the ADT switching method,sufficient conditions are obtained to ensure the mean-square finite-time boundeness of the filtering error system with prescribed H? performance.Using the decoupling lemma,the design method of the asynchronous resilient filter is presented.Finally,Repressilator model is provided to illustrate the effectiveness of the proposed filtering scheme,and the quantitative relationship is analyzed among the system performance,the probabilty of data dropout and the probabilty of parameter perturbation.This part enriches the research results on asynchronous filtering for TDSS,and provides technical guidance for further research on asynchronous synthesis problems of switched systems with complex dynamics.In networked systems,besides the negative factors,such as data dropout,signal quantization,random disturbance,etc,considered in the above research,there are communication constaints caused by limited bandwidth.To reduce unnecessary data updates and save limited communication resources,an event-triggered scheme(ETS)based on aperiodically sampled data is proposed and used to investigate the strictly dissipative control problem for a class of MJS with time-varying delay.To improve the applicability of the result,the transition rate matrix of the MJS is considered to be generally incomplete,namely,the transition rates are allowed to be completely known,or partially known,or even completely unknown.Combining with input-delay approach,a discontinuous and non-positive definite LKF is constructed,which makes the criterion of stochastic stability and strict dissipativity of the closed-loop control system less conservative.Finally,the design method of the event-triggered controller is presented,and numerical examples are provided to illustrate the effectiveness of the proposed method.The research result in this part not only supplements the existing achievements on event-triggered control of networked switched systems,but also provides theoretical reference for the following event-triggered asynchronous control issue of nonlinear MJS.Based on the ETS mentioned above,the asynchronous H? control problem for a class of nonlinear MJS is studied.In order to reduce difficulty of analyzing the nonlinear system,T-S fuzzy linearization method is introduced.The transition rate matrix of the nonlinear MJS is considered to be generally uncertain,where each transition rate is allowed to be completely unknown or only its estimate value is known.This is conducive to improve the applicability of the research result in the case that transition rates can not be accurately obtained in practice.Additionally,considering that it is difficult for the controller and the system to keep the same mode in the complex network environment,an asynchronous controller is designed based on a hidden Markov model,where the premise variables of the controller are also considered to be asynchronous with the ones of the system.Based on the asynchronous premise re-construct method and LKF with less constraints,a stabilization criterion with less conservativeness is derived.Finally,a truck-trailer model is provided to illustrate the effectiveness of the proposed event-triggered asynchronous control method.This part extends the above research result on control problem of linear MJS,and lays a theoretical foundation for the research on event-triggered synthesis problems of MJS under more complex network environment.