Accurate fault location will lighten the work of seeking for the fault and facilitate quicker repair and restoration to reduce the damages due to stop of power supply, once faults occur on the transmission line. To ensure proper operation of the system, it is of great importance to determine the exact fault location when fault happens. For many years, accurate fault location of high voltage transmission line has been paid much attention to.
On the basis of a lot of predecessors’ achievement, at first, some existing methods of transmission line fault location are summarized and those methods’ primary merits and disadvantages are analyzed as well. At second, based on the travelling wave, double ended approach only deals with the first transient travelling wave reaching the two buses of the fault line. Although it has higher reliability, its location accuracy can also be affected by the wave speed which will be influenced by such factors as geographical position, climate, line parameter changes because of the frequency variation. A new double terminal method of travelling wave fault location is introduced in this paper, which can effectively lower the influence of travelling wave speed and transmission line arc. The arriving intervals of the travelling wave from the fault location and reflected wave from fault location are recorded, then these intervals and location are used by the new method and the fault location is obtained by avoiding the wave speed and transmission line arc influences. Then, the results of EMTP simulation show that this method is available and accurate. Finally, the prospects in the research and application of fault location algorithms are described.