基于倒置电桥法的电力电缆故障定位  

Power cable fault locating based on inverse bridge method

作　　者：邢海瀛[1] 陈柏超[1] 张亚迪[1] 田翠华[1] 余梦泽[1] 

机构地区：[1]武汉大学电气工程学院,湖北武汉430072

出　　处：《电力自动化设备》2008年第3期18-21,共4页Electric Power Automation Equipment

摘　　要：针对电力电缆故障定位问题,提出了基于倒置电桥测量电力电缆故障点的方法,根据传统电桥法在电桥平衡的条件下比较故障电缆接线端部到故障点之间的电阻与无故障电缆电阻而确定故障点的基本原理,通过电路变换,将故障处的电阻转移至电桥上,从而消除了故障电阻对测量精度的影响。并且提出了通过外加电路来消除影响测量精度的接地电流的方法。分析了在测量相与故障相电缆电阻等值和不等值2种不同工况下应用该方法进行测量的具体手段以及应用测量数据对故障点位置进行测算的方法。该方法具有测量范围广、精度高、设备简单、易于操作等特点。在PSCAD/EMTDC软件仿真中,应用该方法对不同故障电阻下的电力电缆故障点进行了估算,结果表明该故障定位方法准确、高效。Inverse bridge method is introduced to power cable fault locating,which is based on the theory of classic bridge that sets the fault location by comparing the resistance between fault point and cable end with the resistance of healthy cable. By circuit transform,the resistance of fault point is transferred onto the bridge to eliminate the influence of fault resistance on measurement precision. Based on circuit analysis,an additional circuit is used to eliminate the influence of grounding current on measurement precision. The calculation of fault point location is discussed for two conditions：the resistances of healthy phase and faulty phase are same and different. The proposed method is simple and easy,with larger measuring range and higher measuring precision. Simulations with PSCAD/EMTDC show its higher accuracy and efficiency.

关 键 词：倒置电桥法 故障定位 电力电缆 接地电流 

分 类 号：TM247[一般工业技术—材料科学与工程]