Based On The Traveling Wave Method For Grid Ranging Device Applications

The fault location of transmission line is very important to industrial and agricultural production and the safe operation of power system, but the measure precision and reliability of the fault location device should be improved presently. The thesis makes primary researches on improving the measure precision and reliability of the fault location device.Firstly, the thesis presents the produce and transfer theory of the travelling wave, the principle of the measure method of travelling wave and strongpoints and shortcomings of these methods. The transient travelling wave signal shoule be obtained exactly firstly for improving measure precision based on type A of travelling wave principle, so the key of improving measure precision is the steady and reliable high-speed data acquisition circuit design. For the cause mentioned above, the AD9200 chip that have high speed of convertion was adopted, but the use of high speed ADC bring the contradiction of high speed data acquisition and low speed process of the task. The contradiction was settled by adopting the control structure of MCU+CPLD and the high-speed data acquisition controller and the time reference mark demarcation module were designed with CPLD. The design of double memory backup was made that primarily settle the memory dead-time of those measure settings and improve anti-jamming of settings. During the design of the software, the embedded operation system μCOS-Ⅱ was adopted to simplify software design and improve the reliability of the software.The data communication is needed among devices and sever. By comparing the telephoneline,SMS,GPRS in reliability,cost,maintenance,the wireless communication scheme was put forward based on GPRS and network structure scheme accordingly aimed at above-mentioned question. The program of client and server was designed based on above scheme. Through testing in laboratory, the scheme meets the communication requirement of the equipment, and the cost is lower than telephone line communication.