一种测定三芯电力电缆内各相芯线位置的方法

A method for determining the position of each phase core wire in the three-core power cable

为解决三芯电力电缆质量检验过程中内部各相芯线位置难以测定的问题,提出了一种测定三芯电力电缆内各相芯线位置的方法。具体地,通过在三芯电力电缆外表面轴向横截面对称地安装2个磁传感器,在给该电缆内某单相芯线施加电流激励后,用磁传感器测量所在位置处磁感应强度的切向分量;根据2个磁传感器的测得量值,利用安培环路定理以及该单相芯线中心位置与磁传感器位置之间的几何关系,求解该单相芯线中心到三芯电力电缆中心的距离,以及该单相芯线中心和三芯电力电缆中心的连线与y轴之间的夹角,即可求解出该单相芯线的位置;通过给三相芯线分别施加电流激励,便可分别测得三相芯线的位置,从而实现对三芯电力电缆内各相芯线位置的测定。电磁场有限元仿真试验和解析模型计算的结果表明,此方法准确性高,对三芯电力电缆生产工艺水平提高和质量检验具有指导价值。

In order to solve the problem that the position of each phase core wire is difficult to determine during the process of the three-core power cable quality inspection,a method for determining the position of each phase core wire in the three-core power cable is proposed in this paper.Specifically,after a single-phase core wire in the three-core power cable is given a current excitation,the magnetic sensors are used to measure the tangential component of the magnetic flux density at the position by arranging two magnetic sensors symmetrically on the surface of the three-core power cable.Based on the measured values of the two magnetic sensors,and the Ampere loop theorem and the geometric relationship between the position of the single-phase core wire center and the position of the magnetic sensors,the distance from the single-phase core wire center to the three-core power cable center and the angle between the line connecting the single-phase core wire center to the three-core power cable center and the y-axis are solved,that is the position of the single-phase core wire.The position of the three-phase core wires can be determined by applying current excitation to the three-phase core wires separately,thereby realizing the determination of the position of each phase core wire in the three-core power cable.The results of electromagnetic finite element simulation and analytical model calculation show that the proposed method has high accuracy and guiding value for improving the production level and quality inspection of the three-core power cable.