导线脱冰后的最大跳跃高度和杆塔受力特征是塔头设计关心的核心问题，特重冰区特高压直流线路导线覆冰厚度可达60mm~80mm，超过现有设计规程的最大冰厚。本文建立典型特高压直流连续耐张段线路塔线耦合体系模型，采用有限元方法模拟研究不同档不同极导线脱冰塔线体系动力响应，获得导线脱冰后杆塔的应力、纵向不平衡张力以及导线最大跳跃高度，分析杆塔受力特征及电气绝缘间隙。结果表明杆塔纵向不平衡张力取值大于重冰线路规范要求值，导线冰跳高度大于现有简化公式的计算值。基于研究结果提出特重冰区杆塔纵向不平衡张力取值建议以及对现有导线冰跳高度公式的修正。

Mechanical characteristics of tower and maximum jump height of conductor after ice-shedding are key issue in the design of a tower head. Ice thickness of UHV DC line in ultra-heavy ice zones may arrive at 60mm~80mm, exceeding the maximum value proposed in current transmission line design codes. The finite element models of tower-line systems of UHV DC line sections in ultra-heavy ice zones are set up, and the dynamic responses of the systems with different spans after ice shedding are numerically simulated. Stress and longitudinal unbalanced trension on the towers and the maximum conductor jump height are obtained, and the mechanical characteristics of the towers and electric isolation clearance are analyzed. It is shown that the longitudinal unbalanced tensions are larger than those determined by current deighn code and the maximum conductor jump heights are larger than those by current formulus. The longitudinal unbalanced tension on the towers and the modification to the jump height formula are suggested.

中国电建集团河北省电力勘测设计研究院有限公司科技项目（22-KJDW001）