Fault Location Method Based on the Calculation of the Lowest Voltage along the Line

With the rapid development of large-scale new energy power generation, the demand for long-distance and large-scale transmission is constantly increasing, and high-voltage transmission lines are widely distributed. Determining the fault location quickly and accurately after transmission line fault occurs is of great significance to improving the efficiency and reducing the difficulty of fault maintenance. Traditional fault location is based on the centralized parameter line model to calculate the fault distance. With the increasing access to large-scale and new long-distance energy clusters, grid-connected lines have become longer, and the influence of the line distribution capacitance on the error of ranging results can no longer be ignored. Therefore, this paper proposes a fault location method based on the calculation of the voltage nadir along the line. By using the Bergeron model, the voltage along the line is calculated, the voltage data in the unit data window is complex integrated, and the voltage's complex integral curve is obtained. According to the distribution of minimum points on the curve, a fault location method based on the calculation of the voltage nadir along the curve is proposed. The simulation analysis of
$\mathbf{PSCAD}/\mathbf{EMTDC}$
shows that the proposed method is less affected by the fault transient process and the distributed capacitance of the line, has high fault location speed and accuracy, and is nearly unaffected by the fault time, which greatly improve the fault location accuracy of long-distance transmission lines.