10kV交联聚乙烯电缆终端主绝缘含空气气隙缺陷试验

Experiment of Main Insulation with Air Gap of 10 kV Cross Linked Polyethylene Cable Terminal

为研究电缆终端主绝缘在含有空气气隙缺陷时对电缆终端电场分布的影响,使用基于有限元法的电场仿真软件,建立了静电场下电缆终端含空气类缺陷模型,并进行了相关的电场仿真计算。结合缺陷宽度不同对电场畸变程度的影响,着重分析了电场畸变最大值的分布规律。该规律显示电缆缺陷的宽度与电场畸变的程度成反比例关系,且最大电场场强值已超过正常的电场场强分布规定值。为验证电场仿真的正确性,采用振荡波电压法进行电缆终端含有空气气隙的相关试验,试验指出空气气隙会引发明显的局部放电现象,继而验证了该类缺陷会引起明显的电场畸变。

To research the effect of cable terminal contains air type defect on electrical field distribution,an electric field simulation software applying the finite element method was adopted to establish an electrostatic field model so as to calculate the distribution of electrical field when cable terminal contained air gap.With the different heights of the defects,the distribution rule of the max electric field distortion was analyzed.The rule shows the width of defects and the degree of distortion in electric field is in inversely proportional relationship,and the maximum electric field value exceeds the normal value of electric field distribution requirements.To verify the correctness of the computation,experiments on cable terminal with air gap was carried out by oscillatory voltage method.The test results show that air gap will lead to significant partial discharge phenomenon,verifying that the type of defect will cause significant distortion of the electric field.