A novel decentralised event-triggered control for network control systems with communication delays

This paper studies a novel decentralised event-triggered L∞$\mathcal {L}_\infty$ control for network control systems with communication delays and external disturbances. To overcome the drawbacks that the relative event-triggered mechanism (ETM) generates many events when system is close to the origin and the absolute ETM produces many events when system is far away from the origin, a novel decentralised sampled-data-based ETM is first proposed. By using both local state-dependent and state-independent information, the decentralised ETM can effectively reduce network loads in each channel during the whole operation time. Then, a novel general system model with parameters of the decentralised ETM, communication delays and external disturbances is presented, and sufficient conditions for the ultimately bounded stability and asymptotic stability of the closed-loop system are obtained. Specially, the quantitative relationship between the boundness of the stability region and the parameters of the decentralised ETM is established. Moreover, to overcome the inconvenience of the two-step design method that controllers are required to be given a priori, a co-design scheme is presented to design the decentralised event generators and the output-based controller simultaneously. Finally, numerical examples confirm the effectiveness of the proposed method.