Research On Windage Of V-shape Insulators In UHV

UHV transmission lines have becoming more and more import in economic development of China, with the construction of UHV transmission porjects in recent years. Meanwhile, flash winding accident of insulators endangers the safe operation of electric system.V-Shape insulators have advantages of resisting flash winding accicent and reducing the width of corridor. In order to meet the security of transmission lines and decrease construction costs, deformation characteristics of V-Shape insulators under wind loads are analysed based on finite element method using Abaqus Software. The main works are as follows:(1) Equivalent friction coefficient of spherical hinge between porcelain insulators is derived under several simplified assumption. To analyse the windage characteristics of Vshape porcelain insulators, FEM model is established counting friction and rotation-limit effection of spherical hinge which is simulated with connector element by Join+Rotation.The affection of spherical hinge's friction and rotation-limit to the mechanical characteristics of porcelain insutator is discussed at last.(2) The metarial of composite insulator core is assumed orthotropic, considering the difference of tension and compression; user subroutine of material model is writen by Fortran for Abaqus analysis. Buckling analysis of insulator core and mechanical analysis of V-shape insulators are performed to define the most adverse state of V-shape composite insulators, then minimum angle of V-shape insulators is derived considering compression of composite insulator, and the result is compared with standard.(3) In order to amend the windage loads, which is under the infulance of conductor coupling, height difference of spans and fluctuating wind dynamic amplification, V-shape composite insulator- conductor coupling model is established. Artificial fluctuating wind for transmission line is simulated by WAWS method. The relation between correction factor of windage loads and transmission line parameters, such as, span, height, V-shape angle and wind velocity etc, is discussed after detailed analysis.