【作者】 王金江；

【导师】 刘日良； 张承瑞；

【作者基本信息】 山东大学 ， 机械设计及理论， 2007， 硕士

【摘要】 以太网已在互联网、办公网络和企业管理网络等领域获得了广泛的应用,其技术日臻成熟。以太网被广泛接受的事实,使其具有了在工业控制系统中应用的趋势和可能。工业以太网是将以太网技术应用到工业控制系统,并对其进行改进,以适应于工业控制系统需求而产生的一种控制网络技术。和现场总线相比具有安装成本低、传输速率快、支持服务类型多、用户基础广泛等突出的优点。但是目前工业以太网处于发展阶段依然存在许多不适应现场应用的缺陷,例如网络通讯协议缺乏实时性和确定性、缺乏通用的应用层协议以及网络节点间难以实现同步性等问题。以高性能的运动控制模型分析得出网络化运动控制系统需要通信数据的高性能实时传输、以及快速的同步运动等要求。本文综述了以太网的实时性和同步性研究现状,分析目前几种常用的用于运动控制的工业以太网络,参考IEEE802.3协议以及国家标准《控制与驱动装置间实时串行通信数据链路》,提出了一种基于标准以太网的实时同步网络,给出了网络拓扑结构和工作方法。根据ISO/OSI七层模型,建立了实时同步网络的互连参考模型;制定了实时同步网络的报文结构及内容;给出了实时同步网络的通信时序、同步机制等。分析了MAC_IP的工作原理,并划分各功能模块,选用硬件描述语言VerilogHDL,在开发工具QuartusⅡ设计了符合IEEE802.3协议的MAC_IP核,为以后符合实时同步网络的MAC_IP核的开发打下了坚实的基础。并对顶层模块、发送模块,接收模块、MAC控制模块以及物理层和主机(MCU)的接口以及CRC、CSMA/CD、Hash表等算法进行了详细说明。具有以太网通讯能力的控制模块是开发工业以太网控制系统的基础,本文以基于实时同步网络的电机控制模块为例,详细地介绍了电源电路设计、以太网PHY接口设计、spi总线扩展接口设计、控制单元(MCU)、FPGA开发以及电机控制接口等,并给出了FPGA中QEP电路设计,说明了具有网络功能的控制模块的开发方法。并将开发的MAC IP核经编译综合后,下载到该电机控制模块中,经测试无错包、丢包现象,验证了该实时同步网络的开发的正确性。最后对全文进行总结,并对实时同步网络下一步的研究工作如控制器端实时网络应用程序的解决方案、设备互操作性及应用层协议兼容性研究、组态应用软件的开发、开发基于该实时同步的具体应用等提出了自己的设想。更多还原

【Abstract】 Ethernet has been widely accepted in information domain. It is possible to use Ethernet in industrial control systems. Industrial Ethernet is a kind of field bus technology which applies Ethernet in industrial field environment. Ethernet must be improved in order to meet the requirements of industrial control systems. It has many merits such as low installation cost, high communication speed, supporting variable services and large customer quantity. However Industrial Ethernet is in its developing stage, there still exists flaws that id unsuitable for industrial applications: lack of determinism and real-time property, no unified application layer protocol and lack of synchronization between net nodes.It can be found that the motion control network system has the requirements of the high performance real-time data transition and fast synchronous motion from the analysis of high performance motion control model. It is summarized that the previous study about real-time and synchronization of Ethernet and analyzed a few common industrial Ethernets used for motion control. On reference of the IEEE802.3 protocol and China standard Electrical equipment of industrial machines--Serial data link for real-time communication between controls and drives, an innovative real-time and synchronous control network over Ethernet is presented. A bus topology and working method are applied to the net structure. According to ISO/OSI model, reference model for network interconnection is established. The message structure and contents of real-time and synchronous network are defined. The network timing and synchronization mechanism are also provided.The working principle of MAC_IP is analyzed and the key functional modules of MAC layer are given in this thesis. The implementation of IEEE802.3 MAC (Media Access Control) function is designed based on Altera’s FPGA in this dissertation. Verilog HDL is used for this project. It lays the foundation for the design the MAC_IP that fulfills the real-time and synchronous network protocol. It also describes that the solutions to such as Top module, Tx Module, Rx module, MAC-control and interface between PHY, MAC and host, arithmetic for CRC, CSMA/CD, and Hash Table in this thesis.Control node with network interface is the basic element of network control system. With analysis of actual control system requirements, the motor control node is developed on real-time and synchronous network which includes power design, the Ethernet PHY interface design, SPI interface design, control unit (MCU), FPGA design and motor control interface. The QEP circuit is also designed in FPGA. The develop method of control model with network interface is illustrated. The IP core’s synthesis and assemble ate based on develop tool Quartus II. At last, design module is downloaded in motor control model. It is testified the feasible of the development of real-time and synchronous network by the test of no missing packet and no error packet.Finally, it presents some conclusion of the dissertation and expresses opinions on future work about real-time and synchronous network. It includes the solution of how to develop real-time software in the controller, device interoperability techniques and application layer protocol compatibility, the development of configuration application software and the development of actual application object based real-time and synchronous network.更多还原