煤礦井下電纜單相接地故障測距

礦井配電網為單端供電系統，其中性點不接地或通過消弧線圈接地，當出現單相接地故障時，由于故障電流微弱，故障點位置很難查找。針對該問題，提出了一種基于零模和線模行波波速差的單端行波故障測距法，詳細分析了行波測距理論，闡述了線模波速與零模波速的測量方法。在理想情況和故障點存在過渡電阻情況下的仿真結果證實了該方法的有效性和可行性。

The mine distribution network is a single-ended power supply system, its neutral point is ungrounding or grounding by arc suppression coil. When single-phase grounding fault happened, fault current is weak, so it is very hard to locate fault position. To solve the problem, the paper proposed a single-ended traveling wave fault ranging method based on difference of wave velocity between zero mode component and aerial mode component of traveling wave. It analyzed theory of traveling wave ranging in details, expounded measuring method for wave velocity of aerial mode and zero mode. By the simulation of ideal condition and existence of transitional resistance confirmed effectiveness and feasibility of the method.