IEEE Trans Cybern. 2016 Dec;46(12):2772-2781. doi: 10.1109/TCYB.2015.2489563. Epub 2015 Oct 26.
New stability criteria and stabilization methods on networked control systems (NCSs) with short time-varying delay (STVD) are proposed in this paper. An NCS with STVD is transformed into a time-varying discrete time system. And then, this discrete time system is converted into a equivalent time-invariant system with norm-bounded uncertainties by using robust control techniques. Using this method, the conservatism of the stability condition caused by STVD can be reduced. Based on that, a single norm-bounded uncertainty is replaced by N norm-bounded uncertainties to further reduce conservatism. Theoretical analysis shows that when N is increased, the stability condition becomes less conservative. For a fixed sampling period, the obtained stability conditions explicitly depend on the upper and lower bounds of the time delay. The existence condition and design method for the controllers are also presented. Finally, three numerical examples are provided to demonstrate the effectiveness of the proposed scheme.
本文提出了一种具有短变时滞(STVD)的网络控制系统(NCSs)的新稳定性判据和稳定化方法。通过使用鲁棒控制技术,将具有 STVD 的 NCS 转换为时变离散时间系统。然后,通过使用鲁棒控制技术,将这个离散时间系统转换为具有范数有界不确定性的等价时不变系统。通过这种方法,可以减少 STVD 引起的稳定性条件的保守性。在此基础上,用 N 个范数有界不确定性代替单个范数有界不确定性,进一步降低了保守性。理论分析表明,随着 N 的增加,稳定性条件变得不那么保守。对于固定的采样周期,所得到的稳定性条件明确地取决于时滞的上下界。还给出了控制器的存在条件和设计方法。最后,提供了三个数值示例来验证所提出方案的有效性。