【作者】 金鹏；

【导师】 赵军； 马丹；

【作者基本信息】 东北大学 ， 控制理论与控制工程， 2012， 硕士

【摘要】 随着计算机技术、控制技术、网络技术和通信技术的不断发展,对于网络控制系统(Networked Control Systems)的研究已经成为现代控制理论研究的重要领域之一。在网络控制系统带来成本低、易扩展、资源共享、结构灵活等众多优点的同时,由于通信网络的不可靠性,不可避免地给系统带来了传输时延、数据丢包、通信约束等问题,这些问题直接地影响到系统的性能。如何解决这些问题给网络控制系统带来的影响具有一定的理论和实际意义。本文研究了具有通信约束的网络控制系统的H∞控制设计问题,主要工作概述如下：首先,研究了具有通信约束的网络控制系统的H∞控制问题。假设网络控制系统在运行过程中无数据包丢失和网络诱导时延,根据通信约束的特点,将离散化后的闭环网络控制系统描述成一类离散切换系统。我们利用平均驻留时间方法讨论了系统的指数稳定性,并且通过线性矩阵不等式方法设计了状态反馈控制器以使得系统具有给定的H∞干扰抑制水平γ。其次,在上述情况的基础上,我们考虑网络控制系统运行时,除了具有通信约束,还存在时变不确定时延。通过将时延的不确定性转换为系统状态方程系数矩阵的不确定性,我们将离散化后的闭环网络控制系统描述成一类具有不确定性的离散切换系统。利用平均驻留时间方法给出了系统指数稳定的条件,并通过线性矩阵不等式方法,设计了鲁棒H∞保性能控制器,以保证闭环网络控制系统具有一定的二次性能指标上界,同时具有给定的H∞干扰抑制水平γ。通过仿真验证了结论的正确性和可行性。最后,对本文的主要工作进行了总结,并对网络控制系统的研究进行了展望。更多还原

【Abstract】 With the continuous development of computer technology, control technology, network technology and communication technology, the research of networked control systems (NCSs) has become one of the important areas in modern control theory. Networked control systems have many advantages such as low cost, easy to extend, resource sharing and flexible structure. Due to the unreliability of communication network, it inevitably brings many problems such as transmission delays, packet dropouts and communication constraints, which directly affect the performance of the systems. How to decrease the affection that these problems bring to networked control systems has theoretical and practical significance.In this thesis, we study the problem of H∞control design of networked control systems with communication constraints. The main results are as follows:Firstly, the problem of H∞control of networked control systems with communication constraints is studied, in which we assume that networked control systems are running without packet dropouts or network-induced delays. According to the characteristics of communication constraints, we describe the discretized closed-loop networked control systems as a class of discrete-time switched systems. We use the average dwell time method to discuss the exponential stability of the systems. Then, we use the linear matrix inequality method to design a state feedback controller to ensure a prescribed H∞disturbance attenuation level y.Secondly, on the basis of the situation above, we consider a class of networked control systems with communication constraints and uncertain time-invariant delays. We describe the discretized closed-loop networked control systems as a class of discrete-time switched systems with uncertainty by converting the uncertainty of time delays to the uncertainty of the parameter matrix in state equation of systems. We give the exponentially stable conditions by the average dwell time method when all the subsystems are stable. Furthermore, a robust H∞guaranteed cost controller is designed by using linear matrix inequality approach to ensure that the closed-loop networked control systems have the upper bound of quadratic performance index and a prescribed H∞disturbance attenuation level y. Then we give the simulation results to illustrate the correctness and feasibility of the conclusions.Finally, the results of this thesis are summarized. Moreover, the further research problems of networked control systems are pointed out.更多还原