摘要
针对铝包钢地线遭受雷击后发生损伤乃至断股、断线的机理,国内外已开展多项针对雷击造成地线热烧蚀损伤的研究,但地线的损伤是热烧蚀损伤和机械损伤共同作用的结果,因此有必要对地线在雷击过程中的机械损伤进行分析。首先根据实际雷击地线的物理过程,利用COMSOL软件搭建一个考虑结构动态演变的地线机械损伤评估模型,该模型可以实现地线在雷击过程中存在的结构演变的模拟;接着利用试验数据验证该模型的准确性;最后使用该模型,对地线在各种参数的脉冲分量、持续分量作用下的机械损伤进行计算并评估其损伤结果,确定机械力对地线雷击损伤的影响。研究结果表明:相比于脉冲分量作用阶段,在持续分量作用下,机械力会对地线造成更加明显的损伤;雷击过程中冲击力和电磁力不会对地线造成损伤,但是热应力和轴向拉力的存在会明显加剧地线的损伤,因此在进行地线在雷击作用下的损伤分析时,机械力的作用不可忽略。
Multiple studies have been conducted both at domestic and abroad to investigate the mechanism by which the aluminum-clad steel ground wire is damaged or even broken after being struck by lightning,particularly with respect to thermal ablation damage caused by lightning strikes.However,ground wire damage is the result of both thermal ablation and mechanical damage,it is necessary to analyze the mechanical damage to the ground wire during lightning strikes.Firstly,according the physical process of lightning strike on the ground wire,a ground wire mechanical damage evaluation model was constructed using COMSOL software that considered the dynamic evolution of the ground wire structure during the process.This model could simulate the structural evolution of the ground wire during lightning strike.Then,experimental data was used to verify the accuracy of the model.Finally,this model was used to calculate and evaluate the mechanical damage to the ground wire under various parameters of impulse components and continuous components to determine the impact of mechanical force on the ground wire after lightning strike.The research results show that compared to the impulse component phase,mechanical force will cause more obvious damages to the ground wire during the continuous component phase.The impact force and electromagnetic force during the lightning strike process will not cause damages to the ground wire,but the presence of thermal stress and axial tension will significantly exacerbate ground wire damages.Therefore,when analyzing the damages to ground wires under lightning strikes,the role of mechanical force can not be ignored.
作者
林轩
王珮沣
莫少星
钟枚汕
郭德明
刘刚
LIN Xuan;WANG Peifeng;MO Shaoxing;ZHONG Meishan;GUO Deming;LIU Gang(School of Electric Power,South China University of Technology,Guangzhou,Guangdong 510641,China;Guangdong Artificial Intelligence and Digital Economy Laboratory(Guangzhou),Guangzhou,Guangdong 510335,China;Digital Grid Research Institute,CSG,Guangzhou,Guangdong 510670,China)
出处
《广东电力》
2023年第7期103-114,共12页
Guangdong Electric Power
基金
国家自然科学基金面上项目(51977083)
广东省自然科学基金面上项目(2022A1515011182)。
关键词
架空地线
铝包钢绞线
雷击损伤
机械损伤
有限元分析
脉冲分量
持续分量
overhead ground wire
aluminum-clad steel ground wire
lightning strike damage
mechanical damage
finite element analysis
impulse component
continuous component
