超高压T接线路高精度故障测距算法研究

STUDY ON ACCURATE FAULT LOCATION ALGORITHM FOR EHV TEED LINES

提出一种为超高压 T接线路进行精确故障定位的算法。该算法利用各端正序电压和电流以及线路正序参数首先进行故障支路的判定 ,然后对故障支路按照双端线路进行故障定位。算法以π型等值建立线路模型 ,较为真实地反映出分布电容的存在。算法不需要故障类型的判别 ,不受故障电阻、系统阻抗及负荷电流的影响。 EMTP仿真结果表明 ,该算法精度高且稳定 ,定位误差一般不超过 0 .5 %。

An accurate fault location algorithm for EHV teed lines is presented. By using positive sequence voltages and currents of three terminals as well as line positive sequence parameters, the algorithm identifies the faulted branch line, then evaluates the fault location according to two-terminal lines. The algorithm is established on the basis of π-equivalent line model, which can be more accurate description of the distributed capacitance of lines. The algorithm does not need fault type identification, and is not affected by the fault resistance, system impedance and pre-fault load. The EMTP simulation results show that the location accuracy of the proposed algorithm is stable and high, and the location error is generally less than 0.5%.