时变时延网络系统的滑模控制器研究

Research of sliding mode controller for networked systems with time-varying delay

针对网络控制系统中普遍存在的随机时变时延问题,提出了保证系统渐进稳定的滑模控制方法。通过引入一种能够补偿时变时延的滑模面,在满足可达性条件的前提下得出控制器,并且推导出易于分析的系统滑动模态。然后基于Lyapunov稳定性理论和线性矩阵不等式方法,在设计系统参数的同时证明了系统的渐进稳定性。接着分析了时延变化范围对稳定性的影响,得出保证网络控制系统稳定的最大允许时延上界。最后应用本文提出的方法完成了一组仿真实验,仿真结果表明该控制器能使时变时延网络系统较快地稳定下来,并且可以通过改变滑模参数得到更好的控制性能。

A sliding mode control method is proposed to ensure the asymptotical stability of networked control systems with stochastic time-varying delay. By introducing a sliding mode surface which can compensate time-varying delay, the controller is obtained while satisfying the reaching condition, and a easily analyzed sliding mode is derived. Then, the asymptotic stability of the system is proved and the system parameters are designed based on theory of Lyapunov stability and linear matrix inequalities approach. Next, the influence of delay range on system stability is analyzed. And the maximum allowable delay bound is obtained while ensuring the stability of networked control systems. Finally, a set of simulation experiments is completed by using the proposed method. The simulation results show that the controller can quickly stabilize the networked systems with time-varying delay and good control performance can be achieved by changing the sliding mode parameters.