Research Of Microprocessor-based Protection Equipment For Traction Transformer

Railway transportation is the key way of our country's carrying trade. As an important electric equipment , Railway traction transformer carry weight on steady operation of the electrified railway. With the construction and development of the electric railway at a high speed, automatic devices with better quality and function will be needed. This paper mainly discusses the principle of electrified railway impedance -matching balance traction transformer protection. A scheme and realization of microprocessor-based protection equipment is put forward. In the beginning , this thesis generally introduces the railway power supply system and its characters, especially the developments and actuality of the comprehensive automation system of traction substation. Then the basic nature of electrified railway impedance-matching balance traction transformer, its connection principle and the data selection have been analysed. On the basis of this, the problems existed in the protection of balancing transformer are summarized and the solutions are given. The realizations of the hardware and software are the important parts of the thesis. The CPU for protection adopts 32-bit DSP(Digital Signal Processor) TMS320C32.,which realizes I/O expansion with CPLD(Complex Programmable Logic Device),completes multi-channel high-speed sampling with 16-bit parallel A/D and carries out protective calculation. The CPU for supervision adopts Samsung S3C44B0X, which realizes man-machine interface and communication. Based on the theory in the past ,this paper discusses in detail the configuration and methods of the balancing transformer protection, the realization of software on TMS320C32 DSP board. Futhermore, algorithm and program flow graphs for protection are given. An embedded operation system of uCLinux is installed ,which meets the requirement of Ethernet communication based on TCP/IP protocol by IEC61850 standard. At the last of the paper, the scheme and realization of software on ARM board is discussed particularly. The measure of transplanting embedded operation system uCLinux into S3C44B0X is concretely narrated. And the software of man-machine interface, especially communication by IEC61850 standard is advanced.