Traveling Wave Fault Location Method for DC Line Based on Wavelet Reconstruction Algorithm

Abstract

Aiming at the technical difficulties such as strong volatility of renewable energy, consumption capacity to be improved and fragile transmission channel, flexible DC power grid is proposed. It realizes the flexible dispatching operation of renewable energy and improves its consumption capacity in the form of multi terminal DC interconnection. The development of DC system fault is faster than that of AC system. In order to identify the fault location and eliminate the fault after the fault occurs, the fault location technology of flexible DC transmission line has become a hot research direction. Aiming at the characteristic that the electrical distance of flexible DC line is less than that of equal length AC line, a DC fault location method based on traveling wave location technology is proposed in this paper; Aiming at the difficulty of traveling wave detection caused by medium and high harmonics, a traveling wave head identification method based on wavelet reconstruction algorithm is proposed in this paper. Through the example verification, the method proposed in this paper can be applied to the fault detection of various DC lines, can accurately locate the fault, is conducive to improve the sensitivity and reliability of DC system fault detection, and is of great significance to enhance the strength of DC system.