基于改进多质点模型的输电塔-线体系动力特性评估

An Improved Multi-Particle Model for Dynamic Characteristics Evaluation of Transmission Tower-line Coupling System

在计算输电塔-线耦合体系的动力特性时现有的多质点模型通常忽略输电塔扭转向的作用。为了提高动力特性计算结果的精确性,本文在现有的多质点模型简化计算方法的基础上将扭转向的贡献通过增加自由度的方式纳入到推导方程中,建立了输电导线、输电塔以及塔-线耦合体系动力简化计算的改进多质点模型;使用该模型、有限元分析和试验三种方法分析典型输电塔、线和塔-线耦合体系的平动和扭转固有频率。计算结果显示,理论计算结果与有限元分析结果和试验结果相当接近,验证了该动力简化计算模型的可靠性;当考虑塔-线耦合振动时,输电塔的平面内和扭转向自振频率较相应单塔的自振频率有所降低;在输电塔-线体系结构设计时,应考虑塔-线耦合效应。

When calculating the dynamic characteristics of transmission tower-line coupling systems,the existing multi-particle model often ignores the transmission tower torsional effect.In order to improve the accuracy of the calculation results of dynamic characteristics,based on the existing simplified calculation method of multiparticle model,the contribution of the torsional effect was incorporated into the equation derivation by increasing the degree of freedom.Thus,an improved multi-particle model considering the transmission lines,transmission towers and tower-line systems was established.Then,this model,finite element analysis and experimental methods were all used to analyze the inherent motion frequencies and torsional frequencies of typical transmission towers,lines and tower-line coupling systems.Results showed that the theoretical calculation results were quite close to the finite element analysis results and experimental results.Therefore,the reliability of the simplified calculation model was verified.When considering the tower-line coupling vibration,the in-plane and torsional natural frequencies are lower than those of corre sponding single tower.In the design of transmission towerline system,tower-line coupling effect should be considered.