3D electric field computation of a composite cross-arm

The use of composite insulators for overhead transmission lines has increased in the past decade. Various designs and models are now available for a wide range of voltages. The 3D Finite Element Analysis electric field distribution of such composite insulators has been of considerable interest due to its differences to `conventional´ glass or ceramic insulators. Results of such analysis are now widely available. The present paper presents and analyses the electric field distribution around a composite insulator, which is intended to replace both existing high voltage insulators and the cross-arms of transmission towers. The complex geometry of the composite cross-arm, which includes four separate insulator strings and different shed profiles across these members all connected to a common metallic nose cone, make it difficult to model in any 3D Finite Element Analysis package. The present paper will evaluate the electric fields on such a composite cross-arm, in regards to the areas of high field enhancement.