覆冰输电线路分裂导线舞动的建模与数值模拟

针对以往在覆冰分裂导线舞动的理论模型中缺少对分裂导线扭转刚度进行分析的问题,提出了一种改进的舞动分析模型.将分裂导线等效为单导线,在现有的对单导线舞动建模研究的基础上,采用假设模态法,利用Hamilton变分原理建立了覆冰导线在垂直、水平和扭转方向的动力学模型.考虑到分裂导线和单导线在扭转刚度上的不同,引入了一种分裂导线扭转刚度的计算方法,推导出分裂导线固有频率的计算公式,并将它们应用到所建模型中,使模型能够分析覆冰分裂导线的舞动,用经典Runge-Kutta法对模型进行求解,从而实现了对覆冰分裂导线的数值模拟.以中山口大跨越分裂导线舞动作为实例,由所建立的模型得到的数值模拟结果与实际观测值基本一致,从而验证了模型和数值模拟方法的准确性.

Modelling and Simulation for Iced Bundle Conductor Galloping

Considering torsional stiffness of bundle conductors,an improved model is proposed to comprehensively incarnate and predict iced bundle transmission line galloping.A bundle line is modeled as an equivalent single conductor for taking advantages of single conductor in the previous research.A dynamic model,which accommodates interactions of the vertical,horizontal and torsional movements,is set up with Hamilton variational principle and by assumed mode method.According to the difference of torsional stiffness between bundle and single conductors,a new algorithm for calculating the torsional stiffness of bundle transmission lines is presented,and then the natural frequency of bundle conductors is analyzed.Taking the torsional stiffness and natural frequency of bundle conductors into account,the model enables to describe galloping of bundle conductors.Numerical simulation is performed with Runge-Kutta method for the bundle conductors with large span in Zhongshankou and shows a coincident result with the real observation.