超高压电缆-架空线混合线路故障测寻方法

提出一种超高压电缆架空线混合线路故障测寻的新方法。首先利用有效的判据确定故障发生在电缆侧或架空线侧,然后利用故障区域首末端电压、电流突变量值递推算出故障点。经过简单的改进,该方法同样适用于更复杂的超高压架空线电缆架空线混合线路。新方法不要求双端数据同步,不受线路两端系统阻抗和过渡电阻的影响,不存在伪根判别问题,易于实现。仿真结果显示这种算法具有较高的测距精度和实用价值。

New Method of Fault Detection and Location for EHV Cables with Transmission Lines

A new method of accurate fault location for EHV cable with transmission line is presented. Based on the proposed criterion, the method can discriminate the fault happened in EHV cables from transmission lines, then the fault location can be determined by using the variation of voltage and current obtained from both ends of the connecting lines. The method is also suitable for more complex system such as EHV transmission line-cable-transmission line with only a little changes in the criterion. Simulation results show that the proposed new method does not depend on the data synchronization at both ends of the line and can provide accurate result even if the source impedances and fault resistance are different. The proposed method is easy to implement without false-root identification.