网络控制系统的H_∞状态反馈控制器设计

H-infinity state-feedback controller design for networked control systems

研究了对网络控制系统如何设计H_∞状态反馈控制器.这些网络控制系统中存在不确定的网络时延和数据包丢失.当网络时延和连续丢包有界时,可以将系统建模为具有时变输入时滞的系统,利用Lyapunov-Krasovskii泛函.推导出网络控制系统渐近稳定的充分条件.将这些充分条件转化为带等式约束的LMIs,并对他们进行迭代求解,就可以构造H_∞控制器.与现有结果相比,在推导稳定性条件时本文对交叉项采取了更紧的界定,并且在设计控制器时无需知道调节参数.因此,本文提出的方法具有更低的保守性.仿真结果说明了本方法的正确性和有效性.

The H-infinity state-feedback controller design for networked control systems （NCSs） with uncertain network-induced delay and data packet dropout is studied. Given the bound of data packet losses and the bound of network- induced delays, the NCS can be modeled as a system with time-varying input delay. Based on the Lyapunov- Krasovskii functional, the sufficient conditions for asymptotic stability of the NCS are derived. These sufficient conditions are transformed into LMIs with equation constraints, and the H-infinity controller can be constructed by iteratively solving these LMIs. Compared with the existing results, tighter bounding of the cross terms is employed in deriving stability conditions; moreover, the knowledge of tuning parameters is not required in designing the controller. Therefore, the proposed method is less conservative in design. Simulation example shows the validity and feasibility of the results.