网络化系统的采样周期问题与事件触发控制机制研究

发布时间：2019-03-25 20:02

【摘要】：网络控制系统是近年来控制界的学术热点研究方向。在NCS中,分布在不同物理区域的网络节点之间通过实时通信网络连接形成分布式闭环控制系统。NCS作为一种分布式计算机控制系统,在系统的建模、分析和设计中必然会涉及到信号的采样、保持等问题;另一方面,多个回路以共享网络通信资源的方式进行控制,如何减少冗余信息的传输、提高有限网络带宽的利用率显得相当重要。在网络控制系统的分析与设计当中,采样周期大小的选择既可影响系统的控制性能,又可反映数据信号在网络上的传输状况。目前的研究成果多是基于固定周期采样的方式,这种采样方式尽管利于建模并简化系统分析,但不切合实际甚至会造成网络资源的浪费。考虑到网络控制系统的本质特征,本文工作主要包含如下两个方面:一方面,根据通信网络中数据信息的时变特性,进行时变采样周期网络控制系统的研究。在这方面的工作有两点:其一,研究有界时变时延的变采样周期网络控制系统的2L增益分析,将系统建模为离散区间时变系统,利用李雅普诺夫稳定性定理和线性矩阵不等式技术对系统进行状态反馈控制器设计;其二,针对一类输入多率采样网络控制系统,利用系统的输出预测值,设计系统的动态输出反馈控制器,研究闭环系统的最优保性能控制。另一方面,为了克服周期触发的缺点,避免冗余信息在网络中传输,在保证系统性能的同时节省网络通信资源,本文对事件触发控制机制进行研究。通过建立一种新的混合事件触发控制机制条件,考虑数据包丢失和网络时延的影响,基于输出反馈控制,通过利用线性矩阵不等式技术并构造新的Lyapunov-Krasovskii泛函对闭环系统进行2L增益分析。
[Abstract]:Networked control system (NCS) is a hot research direction in the field of control in recent years. In NCS, distributed closed-loop control system is formed by real-time communication network connection between nodes distributed in different physical regions. As a kind of distributed computer control system, NCS is modeled in the system. The analysis and design will inevitably involve the sampling and holding of the signal and so on. On the other hand, how to reduce the transmission of redundant information and improve the utilization rate of limited network bandwidth is very important to control multiple loops by sharing network communication resources. In the analysis and design of networked control system, the selection of sampling period can not only affect the control performance of the system, but also reflect the transmission of data on the network. Most of the current research results are based on fixed-period sampling, which is helpful for modeling and simplifying system analysis, but it is not practical and even leads to waste of network resources. Considering the essential characteristics of networked control system, this paper mainly includes the following two aspects: on the one hand, according to the time-varying characteristics of data information in communication network, the time-varying sampling period networked control system is studied. There are two aspects in this work: first, the 2L gain analysis of the time-varying sampling period networked control system with bounded time-varying delay is studied, and the system is modeled as discrete interval time-varying system. The state feedback controller of the system is designed by using Lyapunov stability theorem and linear matrix inequality (LMI) technique. Secondly, for a class of input multi-rate sampled network control system, the dynamic output feedback controller is designed by using the output predictive value of the system, and the optimal guaranteed cost control of the closed-loop system is studied. On the other hand, in order to overcome the shortcomings of periodic triggering, avoid the redundant information transmission in the network, and save the network communication resources while ensuring the system performance, this paper studies the event trigger control mechanism. Based on output feedback control, a new hybrid event triggering control mechanism is proposed, which takes into account the effects of packet loss and network delay. By using linear matrix inequality (LMI) technique and constructing a new Lyapunov-Krasovskii functional, the 2L gain analysis of the closed-loop system is carried out.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP273

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