有限元Comsol-Multiphysics的输电杆塔模态分析
本科毕业设计（论文）
基于Comsol Multiphysics的输电
杆塔模态分析
摘要
随着社会的发展，输电线路作为电网的大动脉，其安全稳定的运行关乎着国民经济的稳定。作为支撑输电线的骨骼，输电铁塔的安全可靠运行是电网安全稳定运行的重要保证。但近年来，在各种极端情况下，倒塔断线事故时有发生，严重危害了电网安全。因此，研究输电塔架在各种复杂极端情况下的静动力特性对提高输电线路的安全可靠性有着重要的研究以及工程价值。
本文以有限软软件COMSOL Multiphysics为研究平台，根据已有的设计资料，研究了输电塔架的有限元模型的建立方法，建立了酒杯型直线塔的有限元分析模型，并提出了塔架在风载荷、覆冰载荷、基础沉降等工况下的研究处理办法。根据设计规程，通过分析计算得出了输电塔架在大风作用下的风载荷，并分段施加在输电塔架以实现风载荷的准确施加。风载荷下，最大的位移出现在塔身。然后研究了输电塔架在覆冰、基础沉降等工况下的静力学特性。
最后重点研究了输电塔架的动力特性，对有限元模型进行了模态分析，得到了输电塔架的前10 阶振型以及相对应的自振频率，通过研究发现在塔腿和塔身部分容易过早的出现局部模态。
关键词：输电杆塔；输电塔线体系；静力特性；动力特性
Abstract
With the development of society, the security an stability of electric transmission line system is important to national economy. As the artery of electric network, electric transmission line is a vital implement. Recently, the happening of the collapsing accidents of tower-line system threatened the security of electric network. Therefore, the study of static and dynamic characteristics of the transmission tower has important value both in theory and engineering to improve the safety and reliability of power system.
The finite software COMSOL Multiphysics is used as the analyzing platform in this paper. Based on design information，transmission tower as the glass-shaped tangent tower for analyses is established. In the meantime, the paper advanced the processing methods of different loading cases, such as in wind , ice, foundation settlement.According to the design standards, the subsection wind load of solo tower under maximum wind design are calculated and loaded. The maximum displacement appears in the windward side of tower body.Then the paper studied the mechanical property of transmission tower under extreme cases such as ice, foundation settlement and other working conditions.
Moreover, the mode analyses are carried out considering tangent tower, obtaining its former ten self vibration frequency and vibration mode correspondingly. According to the frequency and vibration mode, finding that part of tower leg and body are tend to appear partial mode.
Key words:Transmission tower; Transmission line system;Static characteristic; Dynamic characteristic;
目录
第一章绪论 (1)
1.1 选题的意义和目的 (1)
1.2 输电杆塔在国内外的发展与研究 (2)
1.3 论文研究主要内容 (3)
第二章输电杆塔体系的建模及分析 (5)
2.1 输电杆塔概况 (5)
2.2 有限元分析软件Comsol Multiphysics (6)
2.1.1 有限元理论概述 (6)
2.1.2 Comsol Multiphysics软件的主要功能和分析过程实现 (7)
2.1.3 有限元建模要求 (7)
2.2 输电杆塔体系模型的建立 (8)
2.2.1 仿真模块的选取 (8)
2.2.2 输电杆塔模型的建立 (8)
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17 3.3 基础沉降作用下的静力学分析 (18)
3.3.1 基础沉降 (18)
3.3.2 输电单塔基础沉降作用下的静力学分析 (18)
3.3.3 输电塔线在基础沉降作用下的静力学分析 (20)
3.4 本章小结 (20)
第四章基于COMSOL Multiphysics输电杆塔模态分析 (21)
4.1 输电杆塔模态分析理论 (21)
4.1.1 输电单塔的自振模态分析 (22)
4.2 模态分析在COMSOL Multiphysics中的实现 (23)
4.3 输电塔线体系的模态分析 (26)
4.3.1输电塔塔模态分析 (26)
4.3.2输电塔线耦合模态分析 (29)
4.4 本章小结 (30)
结论和展望 (31)
总结 (31)
展望 (31)