750kV双跨悬吊式管型母线的力学分析

Mechanics Analysis of the Double Span Suspended Busbar for 750kV Electrical Substation

建立力学模型分析双跨悬吊管型母线在不同工况、管母截面形状、联板安装角和斜拉杆安装角时,管母的跨中挠度、跨中应力和绝缘子串拉力等,将悬吊式管母系统中绝缘子串、绝缘子串下挂点与管母连接处、管母等的静力平衡方程和变形补充方程结合求解得上述参数。分析表明:现有初步设计在自重、覆冰等工况下,跨中挠度和跨中应力均满足规范的要求,理论分析结果与有限元分析结果比较一致;与相同横截面积的空心圆型管母相比,空心椭圆截面管母的跨中挠度减少约10%,绝缘子串拉力不变;通过适度减小斜拉杆安装角,或增加联板安装角,可减小管母的跨中挠度,而绝缘子串拉力变化不大。

An analytical mechanics model was established to analyze the mid-span deflection and stress of the busbar and tension of the suspension cable under different working conditions,different cross-section shapes of the busbar and installed angles of inclined rods.Static equilibrium equations and deformation supplementing equations were combined to calculate the deformation and stress of the suspended busbar system.The results show that under the dead load and ice load,the mid-span deflection and stress of the busbar satisfy the specification requirements.The theoretical results are in agreement with those obtained from finite element analysis.The mid-span deflection of the elliptical cross-section rod decreases by about 10%in comparison with circular cross-section rod with the same cross-sectional area.The mid-span deflection will decrease with a decrease of the installation angle of the inclined rod and an increase of the installation angle of the coupling plate.However,the tension of the suspension cable does not change.