Implementation of Embedded Ethernet in Substation Automation System

Applying Ethernet technology as the communication mode in the substation automation system (SAS) is a new trend. For the equipment located in the bay level of low voltage SAS is arranged low, and it is generally difficult to download the realtime operation system (RTOS) and its implementation of Ethernet communication protocols. This paper studies some key issues in the implementation of embedded Ethernet software, and puts forward an embedded Ethernet software implementation structure characterized by multi-task, time-sharing and layering. The space table method of fairly good real-time character is adopted to manage the memory, and message is organized in the dynamic mode. For the route and address resolution in the equipment located in the bay level of the substation, the equipment just supports the function of address resolution, and the gateway in substation is provided with the address resolution protocol (ARP) proxy, the implementation mode greatly reducing the complexity of the system. In addition, some other issues of the implementation of Ethernet are also discussed.