Electric Field Verification by High Voltage Experiments on the Composite Cross-Arm

The verification of electric field performance is one of the main challenges in the electric design of the fully composite pylon. Electric field computation based on numerical methods such as Finite Element Model (FEM) is an useful method to predict its electric field performance. However, verification of these theoretical computation is necessary. In order to evaluate the electric field distribution on the composite cross-arm surface in the fully composite pylon and assess its electrical design in wet conditions, water induced corona discharge tests on the full-scale cross-arm has been performed. According to test results, the corona inception electric field magnitude on the composite cross-arm surface in wet conditions is lower than the maximum electric field magnitude on the composite cross-arm surface with nominal operation voltage. Thus, the configuration design of the cross-arm needs further consideration, aiming to restrain the maximum electric field magnitude on its surface. Additionally, effects of the cross-arm inclined angle θθcross−arm on the water induced corona discharge activities have been investigated, which gives valuable advice for the decision of optimal inclined angle θθcross−arm .