Research And Development Of Traction Substation Potential Transformer Change-Over Equipment Base On GPRS Communications

The traction substation automation is the fundamental to guarantee the safe and stable operation of the electrical railway. In china, the automation control equipments have been used in the most of the traction substation second system in the electrical railway field, but nowadays there are still have some old equipments been used in the traction substation second system, these old equipments always endangering the security of the traction system, but people doesn't pay enough attention to it.The potential transformer Change-over equipment, which installed in the 27.5KV voltage bus circuit of traction substation,is a old equipment. It is still Composition of the common voltage relays, poor reliability. Therefore ,on the basis of the latest computer technology,this paper carried out the research and development of the potential transformer Change-over equipment, which installed in the 227.5KV voltage bus circuit of electrified railway traction substation.First of all,this papers reviewed the current situation and problems of the potential transformer Change-over equipment, which installed in the 27.5KV voltage bus circuit of traction substation. On the basis of studing the specific circumstances of traction substation, the overall design model of the GPRS based Smart Communications potential transformer Change-ove equipment is achieved.This paper given the hardware design and module design of potential transformer Change-ove equipment in detail. In order to improve the device's performance and reliability, and provide a friendly man-machine interface and the GPRS communications. This project adopt the DSP chip TMS320F2812 as the main board CPU, and also designed the Analog Measurement circuit module, input and output switching circuit module,and human-computer interface circuit module and so on. This device adopt the Plug-in model, through the motherboard integrated with each circuit module. The GPRS communication circuit uses the built-in TCP / IP protocol stack of Huawei's GTM900-B wireless module, simplify the high-frequency circuit's design, to reduce the burden of the main CPU.It is the prominent feature in the software design of this device by using the state machine programming methods to realize the complexity of the logic judgement and GPRS packet analysis. Using the new C/C++ programming way of register-file structure and bit definition to seek Peripheral register of the DSP F2812, which enhance the reading of the software and make it easier.Application of the embedded operating system DSP / BIOS-II is can improved the system reliability and maintainability. After the whole test in laboratory's simulation platform, the results show that the device can make quickly reliable operation, and can achieve long-range GPRS data transmission,and also can provide an intuitive, easy-to-use visual human-computer Interface ,when the error occurred. Through 3 months testing, the device's hardware and software are met the design's requirement.It can effectively shoulder the tasks of the potential transformer Change-over in the 227.5KV voltage bus circuit of electrified railway traction substation, and real-time monitoring of voltage transformer. If the device be used in the production operations,It will be able to increase the traction power supply and reliable operation.