输电线路脱冰不平衡张力数值模拟研究

发布时间：2018-12-15 11:21

【摘要】：输电线路是重要的生命线工程，由冰灾造成的输电塔倒塔多次出现，给社会带来了巨大危害。据2008年雨雪冰冻灾害的灾后调查，冰灾中90%左右的倒塔都是由于不均匀覆冰-脱冰产生的纵向不平衡张力造成。在中国输电线路的设计规范中，仅考虑静态不均匀覆冰荷载，而导线脱冰产生的不平衡张力远大于覆冰静止状态，为保证输电线路覆冰安全，必须考虑其脱冰不平衡张力。本文采用有限元数值仿真方法对脱冰不平衡张力进行了系统的研究，，主要内容如下：首先，本文建立了输电塔-线体系精细有限元模型，并基于非线性理论对输电线初始构形进行了研究。以输电塔影响、脱冰方式和脱冰档位置为研究对象，提出了输电塔-线体系脱冰简化模型，并对其有效性进行了分析。其次，基于本文提出的脱冰简化模型，系统的研究了档数、档距、悬挂点高差、覆冰厚度、脱冰率等参数对脱冰不平衡张力的影响，得出了考虑多参数的脱冰不平衡张力简化经验公式，进一步通过Unzipping形式脱冰模拟研究，给出了考虑脱冰速度影响的脱冰不平衡张力修正公式。然后，基于FLUENT的大涡模拟方法对覆冰导线阻力系数进行了三维仿真，得到了在不同转角下圆形覆冰和新月形覆冰四分裂导线的阻力系数，并对其正确性进行了验证。同时根据谐波合成法，采用双索引频率和FFT算法模拟了输电线路20m/s脉动风风速时程，研究了平均风和脉动风对脱冰不平衡张力的影响，并得出了脉动风动力放大系数值。最后，提出了抗压柔性相间间隔棒的力学模型，比较了三种典型相间间隔棒模型的减振效果。基于相同的脱冰工况，对粘弹铅芯阻尼器的减振性能进行了分析，研究了阻尼器参数类型和布置工况的减振影响，给出了粘弹铅芯阻尼器优化布置方案。
[Abstract]:Transmission line is an important lifeline project. The tower collapse caused by ice disaster appears many times, which brings great harm to the society. According to the survey of rain and snow ice disaster in 2008, 90% of the toppling tower in the ice disaster is caused by the longitudinal unbalanced tension caused by uneven icing and deicing. In the design code of transmission lines in China, only static non-uniform icing load is considered, and the unbalanced tension caused by wire deicing is much larger than that of icing static state. In order to ensure the icing safety of transmission lines, the deicing unbalanced tension must be considered. In this paper, the unbalance tension of deicing is studied systematically by using finite element method. The main contents are as follows: firstly, the fine finite element model of transmission tower and line system is established in this paper. The initial configuration of transmission line is studied based on nonlinear theory. Taking the influence of transmission tower, deicing mode and deicing position as the research object, a simplified model of deicing for transmission tower-line system is proposed, and its effectiveness is analyzed. Secondly, based on the simplified deicing model proposed in this paper, the effects of the parameters such as number of files, spacing, height difference of suspension point, ice thickness and deicing rate on the unbalance tension of deicing are systematically studied. The simplified empirical formula of deicing unbalance tension considering multiple parameters is obtained. Furthermore, through the simulation study of deicing in Unzipping form, the deicing unbalanced tension correction formula considering the effect of deicing speed is given. Then, based on the large eddy simulation method of FLUENT, the drag coefficient of ice-coated lead is simulated, and the resistance coefficient of circular ice-coated and crescent ice-coated four-split lead is obtained at different rotation angles, and its correctness is verified. According to the harmonic synthesis method, double index frequency and FFT algorithm are used to simulate the time history of the pulsating wind speed of the transmission line. The influence of the average wind and the pulsating wind on the deicing unbalance tension is studied, and the dynamic magnification factor of the pulsating wind is obtained. Finally, the mechanical model of flexible interphase spacer bar under compression is proposed, and the damping effect of three typical interphase spacer rod models is compared. Based on the same deicing condition, the vibration absorption performance of viscoelastic lead damper is analyzed, the effects of damper parameter types and layout conditions on vibration reduction are studied, and the optimal layout scheme of viscoelastic lead damper is presented.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TM752;TU31

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