考虑电磁-热-结构耦合的并沟线夹温升特性分析及验证

Temperature rise characterization and validation ofparallel groove clamp considering electromagnetic-thermal-structural coupling

为更准确地研究并沟线夹的温升特性,分析了导线与并沟线夹之间接触点的实际分布特征,建立了并沟线夹的三维电磁、热、结构多物理场耦合模型。基于结构场分析线夹与导线安装和发生热膨胀后导线的接触压力,并计算接触电阻,通过电磁-热耦合得到线夹的电流密度及温度分布规律,探明最高温度的具体位置。分析了不同载流量与螺栓松脱程度对线夹最高温度的影响。研究结果表明:当电流流经并沟线夹系统时,导线与线夹本体接触点界面外侧的电流密度最大,造成的发热最严重;载流量越小,螺栓松脱对线夹的最高温度影响越小,反之,螺栓松脱对线夹的最高温度影响越大;相对误差在3%内,模型具有较高的准确性。

To study the temperature rise characteristics of parallel groove clamps,this paper analyzes the actual distribution characteristics of the contact points between the wire and the parallel groove clamp and builds a three-dimensional electromagnetic,thermal,and structural multi physical field coupling model of the parallel groove clamps.Based on the structural field,the clamp and the wire installation and thermal expansion after the contact pressure of the wire are analyzed and the contact resistance is calculated.The current density and temperature distribution of the wire clamps are obtained by electromagnetic-thermal coupling,and the exact location of the highest temperature is investigated.Finally,the influence of different current carrying capacities and bolt looseness on the maximum temperature of the wire clamp is analyzed.Our results show when the current flows through the parallel groove clamp system,the current density of the wire and the clamp body contact point interface on the outside is the largest,causing the most serious heating.The smaller the current carrying capacity,the smaller the impact of bolt loosening on the maximum temperature of the clamp.Conversely,bolt loosening has a greater impact on the maximum temperature of the clamp.Finally,the accuracy of the simulation model is verified through temperature rise experiments,with an error within 3%.