【作者】 田丽；

【导师】 仲崇权；

【作者基本信息】 大连理工大学 ， 控制理论与控制工程， 2006， 硕士

【摘要】 随着计算机控制、通信、网络技术的发展,以太网技术在工业控制中的应用成为当前控制领域的研究热点。以太网存在通信不确定性,不能满足实时性要求,成为应用于工业现场设备层网络的主要障碍。 EPA(Ethernet Plant for Automation)标准是我国第一部工业以太网标准。通过分析现场设备层信息的实时性要求,提出了EPA系统应用于工业现场设备层的实时通信解决方案。在研究EPA所定义的系统管理、网络拓扑结构、通信模型、时钟同步和应用层服务等功能基础上,重点分析EPA系统的实时特性,讨论EPA实时通信调度方法。进一步研究在网络节点数、交换机级联级数和带宽确定情况下,设备递交时间,时钟同步精度,网络吞吐量,非实时通信带宽和实时通信带宽等实时性能指标的测试目的、测试方法和测试评判,以及实时性能指标间的相互影响和综合指标集的测试方法。 开发EPA系统实时性测试平台,测试设备为嵌入式控制模块DUT5000,以Dynamic C为编程语言。测试界面在Windows环境下以Visual C++为开发工具,开发和研制了可视化、图形化的网络设备实时性能测试软件,测试软件支持EPA系统中的链路调度,支持实时通信服务,支持递交时间和时钟同步精度等指标的测试功能。利用网络分析仪测试网络吞吐量性能,以此计算出非实时通信带宽性能。应用EPA实时性测试平台对863课题组不同厂家的EPA设备进行了验收测试,结果证明EPA系统实时测试平台的有效性,为863项目的顺利验收提供了重要依据。 通过研究和论证,提出的实时性能测试方法具有可行性和正确性,为选择EPA设备和EPA网络提供了依据,对于衡量EPA工业以太网的实时性能有重要实际意义。测试方法也可以推广到其他工业以太网。更多还原

【Abstract】 Ethernet technology applied in the industrial control has become a research hotspot along with the development of the computer control, communication, network technique. Non deterministic communication delay of Ethernet which can’t satisfy the real time request of industrial control has become the main obstacle in application on filed device layer network.EPA (Ethernet for Plant Automation) standard is the first industrial Ethernet standard in China. By analyzing the real time requirement of filed device layer, the real time communication solution that the EPA system is applied in filed device layer is put forward. Based on searching the functions defined by EPA, such as system management, network topology, network communication, clock synchronization and application layer service, this paper pays more attention on the analyzing the real-time performance of EPA system and discussing the real time communication scheduling.-Furthermore, as network nodes, switch cascade connection and bandwidth are fixed on, this paper provides purposes, methods and judgments of deliver time, time synchronization accuracy, throughput, RTE bandwidth and non-RTE bandwidth in EPA system. In addition, it provides reciprocity and testing methods of all the indexes.Developing the platform of EPA system real-time testing, the controlling module DUT5000 is used as the testing equipment with Dynamic C, in the windows, testing interface developed by Visual C++6.0, and designs a visual and graphic node testing software. The software supports link scheduling, real-time communication, the deliver time testing and the time synchronization accuracy testing. The network analysis instrument is utilized to test the performance index of the throughput so that the non-RTE bandwidth can be worked out. The EPA equipments of different factories in 863 Project have been tested by using the platform of EPA system real-time testing, and the results prove the effectiveness of EPA, which provide important assurance for the acceptance of 863 Project.Research and argumentation prove that the real time testing methods are available and correct. The methods provide the references for choosing EPA equipments and network, and have important meanings to the real-time performance of EPA system. The testing methods of this paper can be used in other industry Ethernet.更多还原