浅谈电桥回线法在电缆故障测距中的应用

Preliminary Discussion on the Application of Bridge Back Line Method for Cable Fault Location

在电力电缆故障探测中,电桥回线法是有效的测距方法之一。但是,当电缆发生三相短路接地故障时,由于被测电缆没有完好相线,使得这一方法的应用受到测试条件的限制。根据现场条件,采用不同辅助电缆构成的电桥测试回路,可以解决这类性质电缆故障的测距问题。若辅助电缆与被测电缆的截面积、导体材料不同时,可在测算公式中引入两者的截面积和电阻系数。因此,为解决被测电缆没有完好相的故障测距问题,打开了一个方便之门。同时,也进一步扩宽了电桥回线法在电缆故障测距中的应用范围。

Bridge back line method is one of the most effective means for measuring distance during the power cable fault detec- tion. However, that limits the application of this method by testing conditions when the three-phase short-circuit causes cable grounding faults because of measured cable without complete phase line. According to the site conditions, using the bridge tests loop with different auxiliary cable can solve the ranging problem of this kind of fault cables. When the sectional area and conducting materials of auxiliary cable is different from the measured cable, then the sectional area and resistance coefficient of both can be imported in calculate formu- la. So, it provides convenience for solving the fault location of measured cable without complete phase line. In the meantime, it also expands the scope of application of bridge back line method for cable fault location.