变电站大跨度悬吊式管型母线的变形分析与设计毕业论文
2021-11-07 21:17:29
摘 要
随着国家总体经济的发展,悬吊式管母线得到越来越普遍的应用。本文研究的是某公司设计的悬吊式管形母线,单跨设计长度为48m,材料为6Z63-Φ350/330圆型管母线。本文通过对管型母线进行建模以及对应力、挠度、模态等分析计算,研究管型在各种外部条件下是否符合设计要求,以及分析发生共振时的固有特性。在此基础上对管型母线进行优化设计,这对保证管母线的安全运行有着重要的意义。
本文首先介绍了悬吊式管母线的基本力学特性,建立了平面模型,分析了其在各种条件下的受力情况,计算出相应的应力和挠度。分析了结构振动的原因和减少振动的方法,并通过简支梁模型,探讨了常用的结构固有频率和相应振型的计算方法。其次,通过ANSYS软件对母线建立了有限元模型,以空间结构的模型为基础,对管型母线在各种条件下的应力、挠度进行了计算分析,并与平面模型的计算结果进行了比较,综合比较结果发现结构在应力上远小于许用值,而在变形则有一定的要求。另外,通过对模型进行的模态分析发现,该结构的前几阶固有频率处在一个较小的范围,但对应的振型却较大。最后,本文结合平面模型和有限元模型的分析结果,通过改变配重块的位置和重量,优化结构在一般环境下的变形,优化方案较好的改善了结构的变形,使整体结构更为安全可靠。
关键词:悬吊式管母线;挠度;有限元;优化设计
Abstract
With the development of the country's overall economy, the suspension tubular bus-bar has been more and more commonly used. This paper studies a suspended tube-shaped bus-bar designed by a company, single-span design length of 48m, the material is 6Z63 - Φ350/ 330 round tubular bus-bar. In this paper, through modeling of the tubular bus-bar, as well as the analysis and calculation of stress, deflection, modal mode and so on, the paper studies whether the tubular bus-bar meets the design requirements under various external conditions ,and analyzes the inherent characteristics of resonance. On this basis, optimizing the design of the tubular bus-bar, which is of great significance to ensure the safe operation of the tubular bus-bar.
This paper first introduces the basic mechanical characteristics of the suspended tubular bus-bar, establishes a plane model, analyzes its force conditions under various conditions, and calculates the corresponding stress and deflection. The causes of structural vibration and the method of reducing vibration are analyzed, and the commonly used structural natural frequency and the corresponding vibration calculation method are discussed through the simple girder model. Secondly, through ANSYS software, a finite element model is established for the bus-bar, based on the model of spatial structure, the stress and deflection of the tubular bus-bar under various conditions are calculated and analyzed, and the results of the calculation of the plane model are compared, and the comprehensive comparison results show that the structure is much less than the amount of the use value in stress, but there are certain requirements for deformation. In addition, through the modal analysis of the model, it is found that the first few steps of the natural frequency of the structure are in a smaller range, but the corresponding vibration type is larger. Finally, by changing the position and weight of the counterweight block, the optimization of the deformation of the structure in the general environment is improved by changing the analysis results of the plane model and the finite element model, so that the overall structure can be safer and more reliable.
Key Words: Suspended tubular bus-bar; deflection; finite element; optimal design
目录
摘要 I
Abstract II
目录 III
第1章 绪论 1
1.1 课题背景及意义 1
1.2管母线国内外研究现状 1
1.3管母线事故案例 2
1.4研究内容 3
第2章 悬吊式管型母线力学特性计算及固有特性分析 4
2.1 悬吊式管型母线的基本特性及布置 4
2.2 悬吊式管母线的荷载成分及计算方法 5
2.3 悬吊式管状母线挠度和应力计算 7
2.4 管母线振动原因分析 12
2.5 管母线模态分析 15
2.6 本章小结 17
第3章 悬吊式管形母线有限元分析 18
3.1 静力分析和模态分析 18
3.2 悬吊式管形母线有限元计算与分析 19
3.3 本章小结 24
第4章 悬吊式管形母线优化设计 25
4.1 优化设计总体思路 25
4.2 基于平面结构的优化方案 25
4.3 基于ANSYS对优化结果的分析 27
4.4本章小结 28
第5章 结论与展望 29
5.1结论 29
5.2 研究工作展望 30
参考文献 31
致 谢 33
第1章 绪论
1.1 课题背景及意义
铝合金空心管母线作为大型变电站的电流传输通道,电流最大达到6000A以上,是变电站的主要结构件之一。本文研究的是某公司设计采用的悬吊式管形母线,单跨设计长度为48m,材料为6Z63-Φ350/320圆型管母线。由于管形母线跨度过大,自重较大,加上还有覆冰,风荷载,短路电流等引起来的额外荷载等,在实际过程中可能出现因承载过大而出现结构破坏的情况。
为减少因故障造成的损失,首先对管母线建立相应模型,在考虑各种情况下,如自重、覆冰、短路、风载作用等,对管母线的应力和挠度进行计算和分析,并通过对管母线的变形和模态进一步分析,防止管母线因无法承受这些较为常见的环境因素或者发上共振而导致破坏,引起额外的停电事故,造成生活的不便和经济上的损失。另外,有了分析计算结果的指导,对于后期的维护有着较大的帮助,这不仅提高了供电的安全可靠性,而且可以有效节省后期维护的成本,提高了供电系统整体寿命。
1.2管母线国内外研究现状
目前,国内外都对变电站管型母线的力学行为进行了积极地研究,并获得了不少的成果。