一类时延网络控制系统的最优非脆弱H∞控制

针对一类时延网络控制系统,研究了当存在有限能量外部扰动时,系统的最优状态反馈非脆弱H_∞控制律的设计问题。通过将时延看作系统的时变参数不确定性,应用H_∞鲁棒控制理论及线性矩阵不等式(LMI)技巧,给出了具有控制增益扰动的次优非脆弱H_∞控制律存在的充分条件,提出了最优非脆弱H_∞控制律的设计方法。数值仿真例子表明了所提方法的有效性。     

具有时变时延中立型控制系统的状态反馈镇定

研究具有变时延中立型控制系统的状态反馈镇定问题,首先利用三重Lyapunov泛函方法,通过构造改进型Lyapunov-Krasovskii泛函与利用Jesnen积分不等式,并综合凸组合等方法来有效地估计Lyapunov-Krasovskii泛函导函数尽可能小上界,进而基于线性矩阵不等式(LMI)建立无受控系统的渐近稳定性判据,进而给出控制器设计方案;所得结论易于借助MATLAB工具箱LMI进行验证,最后的数值算例和仿真结果说明了结论的有效性。     

不确定性系统的保性能控制器设计

不确定性普遍存在于各种被控对象中,为了尽量减小不确定性对系统的影响,采用线性矩阵不等式处理方法,导出了状态反馈保性能控制律的存在条件和参数化表示,并据此,通过建立和求解一个凸优化问题,给出了最优保性能控制律的设计方法。该系统能充分利用系统当前状态来设计更加合理的控制器,仿真结果表明该算法的有效性。     

基于线性矩阵不等式的网络控制系统设计方法研究

阐述了基于线性矩阵不等式的网络控制系统的设计方法。概述中指出了网络控制系统的不确定模型,并派生出一个充分的稳定条件。基于这一充分条件,提出了一种延迟依赖线性矩阵不等式方法,该方法通过状态反馈控制来稳定网络控制系统。通过实例证明了线性矩阵不等式方法的有效性。     

时变时延无线网络控制器设计

本文描述了一种对与具有时变时延无线网络系统的控制策略,说明了为什么转发时延和后向时延需要精确地系统识别,并给出了控制方法。为了测量时延,需要远端系统和近端系统的时间同步,文中提出了使用基于IEEE802.11的TSF方法。最后,给出了一种可行的控制器设计的方法。     

一类混沌系统的动态输出反馈控制

为了对一类混沌系统实施控制,提出了利碍新的控制器来控制混沌系统。以往的混沌控制方法只针对个别特殊的混沌系统,而利用动态输出反馈的方法能控制一类混沌系统,这方面的工作以前也曾有过。利用李雅普诺夫稳定理论,结合线性矩阵不等式优化方法,分析了系统的稳定性。数值仿真也表明了所提出的控制策略的有效性。     

有结构不确定的时延多智能体系统一致性

讨论了具有时变结构不确定性的二阶时延多智能体系统的一致性。主要采用LMI(Linear Matrix Inequality)方法,通过构造Lyapunov-Krasovskii泛函,在存在结构不确定性的情况下,对时延多智能体系统一致性的影响进行分析,处理过程中引入自由权矩阵的思想。得到了系统取得一致性的时延相关判据,并进行了理论证明。数值实例和仿真结果也表明了方法的有效性。     

Matlab LMI工具箱在教学和科研中的应用

本文对Matlab线性矩阵不等式(LMI)工具箱软件在教学和科研中的应用进行了研究。笔者首先介绍了工具箱中的三个LMI求解器;然后举了几个例子说明如何间接地使用gevp求解器解决问题,分析了非标准LMI转化为标准形式的方法和手段。另外,本文针对未知矩阵变量中含有分块矩阵的情形,给出了程序描述。     

具有时延和丢包的不确定性NCS的稳定性

研究了同时具有网络时延和数据丢包的不确定网络化控制系统的稳定性.将数据丢失看成一种特殊的时延,利用动态反馈控制器设计提高系统的动态性能,得到了总时滞(包括传感器与控制器之间的时滞,控制器与执行器之间的时滞)的表达式,建立了不确定网络化控制系统模型.通过构造李亚普诺夫函数,采用线性矩阵不等式技巧,给出了系统稳定的判定定理.仿真结果表明了该方法的有效性.     

一类区间控制系统鲁棒绝对稳定性的LMI方法

本文对于区间Lurie控制系统，基于区间矩阵的等价描述和S-过程，构造了关于Lurie型Lyapunov函数中正定矩阵和积分项系数等自由参数的线性矩阵不等式(LMI)，通过LMI的解构造的Lyapunov函数来保证系统的鲁棒绝对稳定性，不必选择和调整参数。不仅讨论了无穷扇形角的情形，而且还讨论了有限扇形角的情形，所获得的结果适用于系统具有多个非线性执行机构的情形。最后给出一个实例说明本文方法的有效性，并通过实例分析了扇形角的大小与鲁棒稳定度的关系。     

Improvement of State Feedback Controller Design for Networked Control Systems

A new method is proposed to improve the state feedback controller design for networked control systems (NCSs) taking both network-induced time delay and packet dropout into account in this paper. An appropriate Lyapunov functional is introduced to establish the improved sufficient stabilizability conditions for NCSs with memoryless state feedback controller by considering an additional useful term when estimating the upper bound of the derivative of Lyapunov functional and introducing new free weight matrices. Based on this less conservative existence condition, a networked controller design method is derived, which is equivalent to the solvability of a set of linear matrix inequalities. Numerical example is given to demonstrate the effectiveness and benefits of the proposed method.     

A New Model for Autonomous, Networked Control Systems

Existing communication utilities, such as the ISO/OSI model and the associated automation pyramid, have limitations regarding the increased complexity of modern automation systems. The introduction of profiles for fieldbus systems, or field-area networks (FANs), was an important innovation. However, in the foreseeable future the number of FAN nodes in building automation systems is expected to increase drastically. And here the authors see an opportunity to revolutionize the operation of intelligent, autonomous systems based on FANs. The paper introduces a system based on bionic principles to process the information obtained from a large number of diverse sensors. By means of multilevel symbolization, the amount of information to be processed is substantially reduced. A symbolic processing model is introduced that enables the processing of real world information, creates a world representation, and evaluates scenarios that occur in this representation. Two applications involving human actions in a building automation environment are briefly discussed. It is argued that the use of internal symbolization leads to greater flexibility in the case of a large number of sensors, providing the ability to adapt to changing sensor inputs in an intelligent way     

New Predictive Control Scheme for Networked Control Systems

This paper is concerned with the design of networked control systems with random network-induced delay and data dropout. It presents a new control scheme, which is termed networked predictive control with optimal estimation. Based on Multirate Kalman Filtering, the measured data which are out of sequence or delayed can be used to improve the precision of estimation. The control prediction generator provides a set of future control predictions to make the closed-loop system achieve the desired control performance and the compensator removes the effects of the network transmission with time delay and data dropout. Simulation results are presented to illustrate the effectiveness of the control strategy via comparing with control schemes without any compensation for the network.     

H-Infinity State Feedback Control for a Class of Networked Cascade Control Systems With Uncertain Delay

Based on practical industrial process control, a typical configuration for networked cascade control systems (NCCSs) is analyzed. This kind of NCCSs with state feedback controllers, in which the network-induced delay is uncertain and less than a sampling period, is studied. The sufficient condition for the stabilizability of the NCCSs without disturbances is proposed, and the state feedback stabilization control laws are derived via Lyapunov stability theory and linear matrix inequality (LMI) approach. For the NCCSs with disturbances, the criterion of its robust asymptotically stability is derived and the $gamma$ -suboptimal state feedback $H_{infty}$ control laws are designed. The $gamma$-optimal state feedback $H_{infty}$ control laws are also put forward by optimizing a set of LMIs. A simulation example of a NCCS for the main steam temperature in a power plant is given to demonstrate the effectiveness of the proposed approaches.      

网络控制系统反馈调度器的设计

本文提出一种基于反馈机理的网络控制系统动态调度器的设计方法.首先利用网络监测器在线获取当前的网络带宽和网络传输误差,预测下一监测器采样周期内可利用的网络带宽.然后利用网络带宽预测值和网络传输误差确定各控制回路采样周期的调节规律,并给出反馈调度器的可调度性约束.当数据包传输发生冲突时,采用MEF(Maximum Error First)作为辅助调度策略,确定数据包的发送优先级.最后通过一组仿真结果验证了所设计的反馈调度器的有效性.     

Deadband Scheduling in Sensor Node and Controller Node for Wireless Networked Control Systems

A deadband scheduling method is proposed for wireless networked control system (WNCS), in which multiple loops share the same wireless network. The bandwidth of wireless network is very limited. The signal transmission among nodes vies for network resources, which will lead to the increase of network congestion and delays in WNCS. Deadbands are set up in both sensor and controller nodes so as to achieve network scheduling. In the sensor node, whether the sensor node sends data packet to wireless network or not depends on a deadband scheduling strategy. The deadband form is according to the difference between current sampling signal and the previous transmission signal, as well as the difference of two consecutive sampling signals. In the controller node, we use the deviations and their variation rate to build another deadband. Simulation results indicate that the proposed deadband scheduling method significantly achieves dynamic performance in WNCS, while effectively reducing network delays and network data packet traffic.     

An Integrated Control and Scheduling Optimization Method of Networked Control Systems

Modern computer and communication network technology has made it convenient to construct networked control systems. Feedback control systems wherein the control loops are closed through a real-time network are called networked control systems (NCSs)[1]. NCSs exhibit the characteristics of high reliability, simple installation, low maintenance, good diagnostic capability, and low cost. Recently, theWhen control and feedback signals transmit through the network, the network delay emerges unavo…     

最少拍无纹波数字控制器设计

本文介绍了对一阶惯性环节控制对象,采用最少拍无纹波控制算法设计的一种数字控制器,并给出了用单片机8098实现的方法.     

基于非线性控制器设计的离散混沌系统同步方法

在混沌通信系统工程化过程中,要求实时信号接收处理,实现收发两端系统的快速同步。为解决该问题,提出了以非线性控制器设计为基础的快速同步方案。针对离散混沌系统,采用Lyapunov函数同步法判定准则和反馈同步原理,合理设计了响应系统中的非线性控制器。仿真结果表明,同步误差可快速地稳定于零点,验证了该快速同步方法的正确性和有效性。