变采样网络控制系统的稳定性分析

目前网络控制系统多采用事件驱动方式,这种驱动方式适用于网络延时小于一个采样周期的网络控制系统。为了解决网络延时大于一个采样周期的问题,提出了事件-时间驱动方式。在采用事件-时间驱动方式下系统成为变采样网络控制系统。在网络时延大于一个采样周期情况下,系统中的控制值和反馈值不能准时到达时,该系统使用预测环节预测的预测值。在基于预测值的变采样网络控制系统中,给出了不同网络时延所对应的状态转移矩阵,分析了变采样网络控制系统稳定需要的条件,最后给出了一个例子说明了变采样网络控制系统采用预测值控制可以使系统稳定运行。

Stability analysis of variable-sampling networked control systems

Event-driven methods are most often used in networked control systems, but this method assumes that request network-induced delays are less than one sampling period.An event-time driven method was developed for network-induced delays longer than one sampling period.With the event-time driven method,the system become a variable-sampling networked control system.When the control value and the feedback value do not arrive at the time,a predictive control value and a predictive forecast feedback value are used in the control system.The state transfer matrices for the variable network-induced delays are analyzed to evaluate the system stability.An example is given to illustrate the stability of the variable-sampling networked control system based on predictive control.