【作者】 王健；

【导师】 李旭光；

【作者基本信息】 东北大学 ， 控制理论与控制工程， 2014， 硕士

【摘要】 随着现场总线控制技术、以太网技术的成熟、性价比的不断提高,网络控制系统具有布线少、易于安装维护和扩展、可靠性与灵活性高、可实现资源共享诸多优点,甚至还具有使用无线网络扩展到难以直接布线的场合的优势,这些优点使它迅速应用于电力,交通,机器人,航空航天等各种系统和远程控制领域。也正是因为如此,网络控制系统近几年成为了国际控制理论界十分热门的研究论题。对于一个网络控制系统而言,首要任务就是要确保这个系统的稳定性,在满足稳定性的条件下,对系统的动态特性也会有一定要求,采样作为一个控制系统的重要组成部分,研究采样问题对控制系统性能的影响就有了很重要的实际意义。本文在前人的研究基础上,研究了一种新的采样方法——超采样,针对在不同的采样方法下,系统动态特性的变化,从以下几个方面进行了研究：(1)本文研究了网络控制系统的最优化设计问题,包括理论研究方法的介绍,单采样和超采样的最优化设计。在MATLAB环境下,针对同一个网络控制系统,单采样与超采样同时最优的情况下,对两种采样方法对系统特性的影响进行了仿真,得出系统在超采样的情况下动态特性优于单采样的情况。(2)为了验证得出的仿真结果,搭建一个网络控制系统实验平台。包括软件平台MATLAB/Simulink,数据采集卡,驱动电路以及直流电机。(3)通过MATLAB和Simulink的数据采集工具箱编写实验平台控制程序,重点包括直流电机参数辨识,网络控制系统的控制框图设计,超采样程序实现和电机的死区补偿等问题。(4)实验结果表明：在单采样情况下,当采样为最优周期时,系统的振荡次数更小,调节时间更短。在超采样情况下,当采样序列为最优周期时,系统的振荡次数更小,调节时间更短。对比于最优周期下,系统在超采样的情况下要比单采样下调节时间更短,而且振荡次数更少。值得指出的是在单采样是最优时而超采样不是最优时上面结论就不一定成立了。更多还原

【Abstract】 As the field bus control technology and Ethernet technique mature, what’s more, their cost performance is keeping improving. Networked control systems have a lot of advantage. Such as less wiring, easy to install and maintain and extend, realize resources sharing and, what is more, arrangement of wire to complicated place by wireless networks. Therefore networked control systems are applied quickly in many domains, such as power, traffic, aerospace, remote control territory and so on. Hence networked control systems has become a very hot topic internationally. Stability is the most important for a networked control system. On the condition of system stability, there will be certain requirements for system dynamic performance. Sampling is one of important parts for a control system and then the research about the influence of sampling on system performance is of great significance. Based on the forefather’s research, a new sampling method, named hyper-sampling, is studied. The thesis is to study the system performance under different sampling method. Some research will be done from the following aspects.First, the optimal design of networked control systems is proposed, including the theoretical research approach introduced and the optimal design under single-sampling and hyper-sampling. When single-sampling and hyper-sampling both are optimal, the influences to a networked control system is simulated by MATLAB. The simulation result show the system dynamic performance under hyper-sampling is better than single-sampling.Second, designing an experimental platform about networked control system is to verify the upper simulation result. The platform consist of MATLAB/Simulink, data acquisition card, the drive circuit and DC motor.Thirdly, the control program of platform is compiled through MATLAB and Simulink Data Acquisition Toolbox. The parameter identification of DC motor, the designing of control block diagram, the hyper-sampling realization by Simulink and DC motor dead-time compensation are included in this part.Finally, the conclusion are the following points. In the case of single-sampling, the networked control system under the optimal period have shorter setting time and smaller maximum overshot. The same condition is the same with the hyper-sampling. When the hyper-sampling and single-sampling are optimal, the result revels that system have shorter setting time and smaller number of oscillation under hyper-sampling. However, it is not always true when the single-sampling is optimal and hyper-sampling is not optimal.更多还原