采用有限元法建立35 kV硅橡胶预制式电缆终端缺陷模型并进行静电场仿真。针对电缆终端可能出现局部放电的位置，分别用三角形和等腰梯形模型模拟割伤和凹陷气隙缺陷，并建立等比例不同大小的缺陷模型分析其最大场强。利用最小二乘法对试验数据进行插值拟合，得到各位置不同尺寸模型的最大场强分布曲线。该曲线表明铜屏蔽层断口处是容易引起电场畸变并产生局部放电的薄弱环节；同位置割伤缺陷较凹陷缺陷场强大；半导电层断口处由于应力锥的疏散作用场强较小，减小了局部放电的可能；铜屏蔽层断口到半导电层断口之间的区域，存在微间隙缺陷时长期运行可产生局部放电。所得结论对高压电力电缆终端的设计、制作及安装等有一定的指导意义。%The defect models of 35 kV prefabricated silicone rubber cable terminal are established and simulated in the static e-lectric field by finite element method .Triangle and isosceles trapezoid models are established to imitate incise lesion and sag defects where partial discharge may occur .Defects with different size and same length -width ratio are built to calculate the maximum field strength .The figure of maximum field strength is curved with the least square interpolation data .The results in-dicate that it is easy to cause the electric field distortion and partial discharge at the fracture of the copper shield .The electric field strength of incise lesion defect is higher than that of the sag one at the same place .Due to the effect of evacuation of the stress cone , it is less likely to cause partial discharge at fracture of semi -conducting layer .The areas between the fracture of copper shield and semi -conducting layer with micro air gap may cause partial discharge in the long -time run.The conclu-sions provide the guidance on the design , manufacture and installation of HV cable terminal .
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