Research On Communication Manager Based On ARM9 And FPGA

With the rapid development of economy, the demand for energy is increasing. As one of the important energy power, the degree of automation of electric power’s transport management system is increasing. The information collection, integration and management of the electric power automation system are getting more and more attention in our country. The data exchange between different intelligent devices is more and more frequent, but different devices using different protocols for substation communication brings a lot of trouble. A feasible solution is to use the communication manager. As an important data forwarding equipment, communication manager has played an important role in the substation communication. It can receive real-time communication data from field devices, and realize the communication and control function after collecting and sorting. At the same time, the development of high-performance microprocessors and the wide application of embedded operating system also provide the basis for the development of new communications manager.According to the functional requirements of substation communication manager and the comparative analysis of a variety of solutions, we design a new communications manager based on ARM + Linux. This architecture uses relatively mature technology and has strong expansibility, so it has good application prospects. This system can be through the RS485, CAN and Ethernet interface to connection with intelligent substation equipment, and send data to the superior master station system through the uplink network interfaces after collecting and sorting. On the other hand, it can receive control commands from master systems, convert and forward the commands to the field intelligent devices, to control the downstream equipments. The system adopts the modular design, to ensure the stability and reliability of it.The system hardware platform adopts ARM + FPGA architecture. Among them, AT91RM9200 industrial-grade chip is chosen as the master chip to be responsible for the control of the whole system, interaction and communication. As coprocessor, FPGA is responsible for extending communication serial port, outputting alarm and control signals to control the controlled objects. ARM and FPGA communicate with each other through the bus to ensure the stability and rapidity of the communication.In the system software section, the basic development knowledge of the embedded Linux operating system and the realization of the transplantation methods are introduced in this paper, and the coprocessor FPGA driven development under Linux system also be focused on. The core of this paper is to achieve protocol conversion. On the protocol conversion method, we use the multi-thread technology to ensure interoperability between the various threads. In addition, the frame structure of the power system communication protocol is analyzed in this paper in order to providing a theoretical basis for the protocol conversion programming.After design, we build the experiment platform to test the system hardware and software environment, system functions and system performance. The results show that the system is stable, and realize the basic function, but system performance still need to be further improved.