介绍了西江500 kV同塔四回路大跨越塔的工程概况，对大跨越单塔和塔线体系进行了动力特性分析，并比较了大跨越单塔与塔线体系动力特性的差异。单塔和塔线体系均首先出现x轴弯曲振型，然后是y轴弯曲振型，再是z轴扭转振型；单塔的y轴弯曲振型频率和z轴扭转振型频率低于塔线体系。结果表明：大跨越塔的结构体系布置合理，导线提高了塔线体系的y轴弯曲和z轴扭转刚度。

The project of 500 kV four-circuit on one large crossing transmission tower in Xijiang was introduced. This paper analyzed and compared the dynamic characteristics of single tower and tower-line system. Both in the single tower and tower-line system, the first modal is x-axis bending vibration, the second modal is y-axis bending vibration, and the third modal is z-axis torsional vibration. The y-axis bending vibration frequency and z-axis torsional vibration frequency of the single tower are smaller than those of the tower-line system. The results show that the structural system layout of large crossing transmission tower is reasonable and the wire can improve the bending stiffness of y-axis and the torsional stiffness of z-axis.