Design On Communication Processing Device In Distributed RTU System

Electric power system is composed of power plant, power transmission and transformation system, power distribution system and many kinds of electrical load. All levels of control center are in charge of the controlling and management of the whole system. To maintain the reliability of the system and keep it run economically, the control center must supervise the whole condition of the system timly and exactly. RTU plays an important role in the computer monitoring system. It is also vital to keep the system run safely and constantly, and to make the system more economical.Based on the thorough investigation of domestic and overseas RTU, a communication processing device implied in distributed RTU system is designed in the paper. It adopts standard industrial PC/104 CPU. In hardware design, using the abundant external resource, a device with multiple serial port, double field-bus network and double Ethernet is developed, which also some functions, such as display, keyboard operation, double machine backup and precise time synchronization。In software design, the OOP and pSOS are employed. Self-defination database, port driving and management are combined together. The independence of each port is guaranteed. In protocol design, in order to reduce redundant code and shorten the period of protocol developing, the difference and resemblance in processing between master protocol and slave protocol are adequately considered, and class inheritance is used.Based on the standard CPU board and fully developed embedded run-time operating system-pSOS, the communication processing is designed with little volume, great processing capability and good stability. Inheritance, polymorphy and packet in orient-object technology are used to make the program easier to be tested and maintained. In order to work together with relay and other intelligence device work conveniently, many protocols are developed. The field running shows that the designed hardware and software can fit well and the anticipative design objectives are achieved.