Research And Design Of Fault Location Based On Travelling Wave In Transmission Lines

With the rapid development of the power industry, power system continues to expand the scale, the transmission power and transmission line voltage level is continuously improving, and the amount of the transmission lines with high voltage and long distance is gradually increasing. If the high voltage lines in the event of failure will cause a great loss, so we need the rapid, reliable and accurate fault location based on travelling wave for the high voltage lines.In order to reduce the cost of the fault location based on travelling wave, to futher improve its reliability and accuracy, with the detailed analysis and comparison of the existing algorithm and with the rapid development of modern microelectronic technique, analysing briefly the basis theory, such as wavelet transformation, fault type of the transmission line, transient process of the travelling wave, and so on. By analysing and comparing the existing algorithms, discussing again the algorithm about the reflection coefficient of the current travelling wave with capacitive terminal. In order to cut down the cost of the fault positioning systems, selecting type A principle of travelling wave location. Choosing Karrenbauer matrix as the phase-mode transformation matrix to reduce the calculation error. Discussing the relationship between the structure of the transmission lines and the sampling frequency, which is key to identify the reflective travelling wave effectively in the third category busbar. Descomposing the fast algorithm into subalgorithms described by pseudo-code and flow chart, which isn't coupled with each other. Selecting FPGA to realize all the functions of the positioning system reliably, which can integrate more complex functions and implement parallel operation. By analysing and researching the relevant chip's performance, choosing proper chips to design the printed circuit board (PCB). Lastly, validating whether the design of the fault location algorithm based on travelling wave in transmission lines is reasonable or not, in which the fault data is from the simulation software PSCAD.The debugging results of the locating equipment indicate that, the designed fault location based on travelling wave in transmission lines meets the demands of the fault location, reducing the cost, enhancing the reliability and the accuracy.