In order to improve the insulation capacity of cable connector (Cc) in the high voltage equipment box (Hveb), this article proposes an optimization scheme that does not change the size of the Hveb and the structure of Cc fittings. In this article, the change in the impulse voltage withstand value of Cc after installing insulating sheath was verified by the lightning impulse flashover test. Based on the finite-element software and the structure of Cc fittings, a special shaped shielding ring (Sr) was designed to adjust the partial area where the electric field intensity are concentrated. Besides, the optimal parameters of the Sr under different working conditions were determined by the orthogonal design. Finally, utilizing ultraviolet (UV) imaging technology and image processing method, the discharge intensity of Cc fittings were characterized. The results demonstrate that with the combination of insulation measures, the impulse voltage withstand value of Cc can be increased from 155 to 235 kV. The maximum electric field strength on the surface of bolts and metal electrode can be reduced by 57.8% and 72%; UV discharge facular area had an exponential relationship with the applied voltage, the initial discharge voltage of Cc can increase by 243% after installing the Sr.

中文翻译：

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标准雷电冲击电压下CRH2动车组电缆接头的绝缘加固


为了提高高压设备箱(Hveb)中电缆接头(Cc)的绝缘能力，本文提出了一种在不改变Hveb尺寸和Cc金具结构的情况下的优化方案。本文通过雷电冲击闪络试验验证了安装绝缘护套后Cc冲击电压耐受值的变化。基于有限元软件和Cc金具的结构，设计了异形屏蔽环(Sr)来调节电场强度集中的部分区域。此外，通过正交设计确定了不同工况下Sr的最佳参数。最后，利用紫外（UV）成像技术和图像处理方法，对Cc配件的放电强度进行了表征。结果表明，结合绝缘措施，Cc冲击电压耐受值可从155 kV提高到235 kV。螺栓和金属电极表面最大电场强度可分别降低57.8%和72%； UV放电光斑面积与外加电压呈指数关系，安装Sr后Cc的初始放电电压可提高243%。