Design Of Distributed Transformer Substation RTU Based On DSP And CAN BUS

With the rapid development of computer technology, communication skill and control technique, Power-automation technique has also obtained speediness development, the wide use of power electronics and non-linear equipment, more attention has been paid to the quality of power system. By real-time metering, monitoring and analyzing the power parameters people can take further steps to improve the safety and the stability of power supply greatly.In the beginning, this paper takes an overall investigation on development and research of both overseas and domestic RTU. And a brief introduction about the development of DSP and its applied in the power system is given, a brief introduction about Field bus applied in the automatic power system and the development of RTU structure is given, the novel transformer substation RTU system with distributed structure based on CAN BUS is introduced in detail. Then this paper presents measuring arithmetic about all kinds of power parameters.This paper adopts the DSP and CPLD technology in hardware, correspondingly systemic integration degree and reliability have been improved remarkably. In order to enhance the precision of the system, and to reduce synchronization error, this paper adopts hardware synchronization. In software modularizing method is taken, simultaneity this product makes a full use of the interrupt resources of DSP, the aim to solve multi-tasks request to DSP and intercross question is reached, the advantage is that systemic real-time ability and the running efficiency of software have been improved. In addition, this paper quotes DL/T634-1997 Standard of RTU communication protocol established by the ministry of Chinese electric power. Furthermore, according to the corresponding communication characters of RS232 and CAN bus, some simplicity and modification have been made in practice to increase its practicability. Moreover, a brief introduction about the development and programme technique of C24xxDSP chip is given. Experiments to verify the electric parameters metering technology are carried out, and the experimental results are satisfying.