Event-triggered Output Regulation Problem For Switched Systems With Severely Unstable Dynamics

With the in-depth advancement of intelligent manufacturing,the model of control object in engineering is becoming more and more complex,presenting typical switching characteristics such as multi-modality and multi-controller.In practical applications,the switched systems may contain severely unstable dynamics(SUDs)due to failure or uncontrollability of the subsystem.SUDs include the unsolvable output regulation problem of each subsystem and destabilizing switchings at partial switching instants,that is,Lyapunov function does not decrease monotonically in activation intervals of each subsystem and increases at partial switching instants.With the expansion of the engineering area,the remote control method realized by network transmission has been applied to the switching system.The open network structure between the subsystems and the controllers of switched systems with SUDs in the network environment not only improves the production efficiency,but also causes problems such as limited communication and network attacks.The interaction among SUDs,network attacks,limited communication and external disturbances brings great difficulties to the analysis and control of switched systems.Therefore,this dissertation takes the switched system with SUDs as the research object,reveals the interaction rule between network attacks,network-induced phenomena and SUDs and constructs a joint design framework for switching strategies,event-triggered mechanisms,controllers and the solvability criteria of output regulation problems,which mainly includes the following works:(1)The mode-compared memory-based event-triggered output regulation problem for switched systems with SUDs is studied.A memory-based mode-compared event-triggered mechanism is proposed,which uses historical sampling outputs to reduce redundant triggerings caused by high oscillations of SUDs and compares subsystem modes to effectively shorten the length of asynchronous intervals caused by the mismatch between triggered instants and switching instants.A novel switching strategy is derived with a constraint on the ratio of total destabilizing switchings to total stabilizing switchings,which relaxes the requirement of the regular arrangement of destabilizing and stabilizing switchings.By designing the dynamic output feedback controller,the solvability criteria of output regulation problem are presented for switched systems with SUDs based on the mode-compared memory-based event-triggered mechanism.(2)For switched systems with SUDs,the output regulation problem under long-duration Do S attacks is studied based on mixed event-triggered mechanisms.In order to describe the situation where the Do S attack duration may be longer than the total dwell time of several adjacent activated subsystems,the long-duration Do S attacks of switched systems are considered for the first time.By imposing inequality constraints at switching instants,the consecutive asynchronous switching of subsystems is allowed,which means the subsystem switches several times but the controllers are blocked by long-duration Do S attacks and fail to switch correspondingly and is difficult to avoid under the current framework of average dwell time.Combined with long-duration Do S attack parameters and destabilizing switching information,a switching strategy that tolerates SUDs and Do S attacks is designed,and mixed event-triggered mechanisms are constructed which reduce the network burden under the long-duration Do S attacks and improve the performance of the switched systems with SUDs.By designing the dynamic output feedback controller,the criteria are established to ensure the solvability of output regulation problem for switched systems with SUDs based on the mixed event-triggered mechanisms.(3)The output regulation problem based on the dissipative property is studied for switched systems with SUDs under integrity deception attacks.The integrity deception attacks unique to the switched systems is delineated for the first time to describe the case where the system output,control signals and switching signals are all tampered by the integrity deception attacks.Combined with the dissipative parameters,integrity deception attacks parameters and destabilizing switching information,two resilient event-triggered mechanisms are devised for sensor-to-controller and controller-to-actuator channels to achieve the balance between limited network resources and system performance against destabilizing switching and integrity deception attacks.A switching strategy captured attack parameters and destabilizing switching information tolerates integrity deception attacks and SUDs.The consecutive asynchronous switching caused by integrity deception attacks is solved effectively by adding the matrix inequality condition at switching instants;By designing the dynamic output feedback controller,the criteria are obtained to ensure the solvability of output regulation problem with dissipative property for switched systems with SUDs based on the resilient event-triggered mechanisms.