Influence of Air Gap on Electric Field of the EMU Roof Cable Terminal

摘要

The semi-rigid cable terminal of high-speed EMU will inevitably generate air gap during the production process. The air gap can cause partial discharge during the normal operation of the train, which would deteriorate the internal insulation and cause terminal explosion failure in severe cases. This paper has studied this kind of problem, analyzed the internal composition of the cable terminal, and simulated the distribution characteristics of the electric field when the air gap at different internal positions. The results showed that the internal insulation layer and the stress layer were more likely to cause insulation breakdown failure when the air gap existed. The air gap length had little effect on the electric field distribution. And the depth of the air gap along the insulation layer can influence the electric field. The weak points in the cable terminal manufacturing process have proposed.