适用于集中参数单端测距模型的距离修正方法

Improved Algorithm for the Lump Parameter Based Single-ended Fault Location Models

提出了一种能够有效提高基于集中参数输电线路模型的单端故障测距精度的修正方法。根据集中参数线路模型算法的实测距离,换算成与模型匹配的正序测量阻抗。另外,基于输电线路贝瑞隆模型,推导出金属短路时应测的故障环路正序阻抗与实际距离的对应关系。通过测量阻抗将实测距离和实际距离关联起来,形成修正公式,在理论上消除了线路分布电容带来的误差。该修正算法基于工频量,对采样率要求不高,具有较高的工程实用价值。大量的ATP仿真试验验证了距离修正的有效性。

A revised algorithm is presented with the accuracy of all single-ended fault location algorithms improved, which are based on the lump parameters model. The measured distance of the lump parameter circuit model can be converted to the correspondingly matching positive sequence measured impedance. And the relation between the real distance and the positive sequence measured impedance of the fault circuit based on the Bergeron model can be derived from solid-grounded faults. The improved algorithm resulting from the relation of the real distance and the measured distance is then obtained, Theoretically, the proposed algorithm is independent of the shunt distributed capacitance of transmission lines. Besides, it is based on the power-frequency voltages and currents. Therefore, it does not need high sampling rate and can be easily implemented in protection devices available. A variety of ATP simulation results have shown the effectiveness of the algorithm proposed.