Research On Power Information Transmission System Based On Embedded Ethernet

With the improvement of the automation level in power plant and substation and the construction and development of the State Power Data net, in order to satisfy the developmental request of the power dispatch automation system, the usual power telecontrol system will be replaced by the network-based telecontrol system with the integration of computer, protection, control, network, and communication technology. This will eventually break the existing specialized division of profession and cause a revolution to the telecontrol system. The transmission system of power information plays vital role in the network-based telecontrol system. The network-based telecontrol system of power system must have the capability to support the network communication. As the implementation of IEC61850 in the future, applying Ethernet technology as the communication mode in the substation automation system is a new trend. Therefore, this paper focuses on the technology to support network communication based on Ethernet.In this paper, firstly, the network reference model, the frame format and the process to establish a TCP link of the IEC60870-5-104 are presented in detail. This is the foundation for the implementation of IEC60870-5-104 in the programming. Secondly, this thesis investigates the embedded Ethernet technology in depth, and analyses the application of embedded Ethernet in the substation automation system, and summarize the advantages and disadvantages of the implementation for embedded Ethernet at present. This thesis puts forward an embedded Ethernet interface implementation based on MCU in low configuration and TCP/IP protocol stack, which can be used for the Real-time data transmission in the substation automation system. Besides, this thesis analyzed the hardware of the embedded Ethernet interface, selecting the right Ethernet controller and TCP/IP protocol stack, and programmed the software communication of the embedded Ethernet interface using Keil uVision3 integrated development environment. This scheme reduces the cost of the product greatly, because it bases on MCU in low configuration, and it can save system resources effectively. Also, it's good for the use of flexible and the easy expansion of function, and users can implement the protocol they need according actual needs. Finally, this thesis implements the network communication module using Visual C++ integrated development environment on PC. As a result, the scheme of the embedded Ethernet interface is proved practical.