Design And Analysis Of Event-triggered Networked Predictive Control Systems

The prevalence of communication network has led to networked control systems replacing traditional control systems,with the controller manipulating controlled plant remotely to achieve a high degree of system decentralization.In practice,a series of problems such as network delays,packet dropouts,and packet disorders are introduced into the system with the use of communication network.Among the many methods to solve network communication constraints,networked predictive control method has received widespread attention for its ability to actively compensate for the adverse effects of network communication constraints.Meanwhile,due to the limited network bandwidth resources,a control method that can avoid transmitting redundant data,which is called event-triggered control,has caused a surge of research.The event-triggered mechanism can significantly reduce the number of data transmissions compared to time-triggered,ensuring system performance while saving network resources.Therefore,this paper will combine networked predictive control and eventtriggered mechanism to design and analyze a class of discrete linear systems.The main research works are as follows.(1)For a networked control system with communication constraints,a time-delay observer that can tolerate part(or even all)of the backward channel delay is designed and theoretically analyzed from the two cases of system open-loop stability and system state can be detectable,respectively.Numerical simulation results are used to compare with the conventional observer,and it is found that the time-delay observer can tolerant a larger backward channel delay than the conventional observer.In order to meet the actual situation of most systems,the observer designed in the second case is used for subsequent state observation.(2)Based on the observer designed in(1),an event-triggered mechanism is introduced and a control method is designed.The sufficient conditions for the stability of the closed-loop system are obtained by theoretical analysis,and the effectiveness of the method is verified by numerical simulation.Since the observer tolerates the delay with an upper bound,a networked predictive control method is designed in the controller to actively compensate for the part of the delay that the observer can't tolerate according to different cases.At the same time,the forward channel delay is compensated by this method,and stability analysis and simulation are performed to verify it.(3)The incremental control scheme is designed to realize the output tracking control of the system with time-delay observer and event-triggered mechanism.And the problem that the steady-state error is not zero when the model parameters are inaccurate is solved.The conditions for the closed-loop system to ensure the asymptotic stability are obtained through stability analysis and verified by simulation,which confirms the effectiveness of the method.