强风区高压输电线路铝线夹疲劳断裂机制研究  

Fatigue fracture mechanism of aluminum terminal connector for high voltage transmission line in strong wind area

作　　者：刘阳 徐凯 郜宁 王晗 肖文凯[2] LIU Yang;XU Kai;GAO Ning;WANG Han;XIAO Wenkai(Electric Power Research Institute of State Grid Xinjiang Electric Power Co.,Ltd.,Urumqi 830000,China;School of Power and Mechanical Engineering,Wuhan University,Wuhan 430072,China)

机构地区：[1]国网新疆电力有限公司电力科学研究院,新疆乌鲁木齐830000 [2]武汉大学动力与机械学院,湖北武汉430072

出　　处：《武汉大学学报（工学版）》2020年第2期176-182,共7页Engineering Journal of Wuhan University

基　　金：国家电网公司科技项目资助(编号:SGXJDK00DYJS1700100).

摘　　要：为探究西北强风地区铝设备线夹频繁断裂的原因,对发生断裂的线夹类型进行了金相分析、成分分析、力学性能测试、有限元模拟,并在摆动疲劳试验机上进行模拟疲劳试验。结果表明,线夹材料的相关性能满足现有国家标准,但在西北地区的实际工作条件下,当风力达到7~8级时,其所受的应力最大值超过材料的屈服强度,应力集中区域发生塑性变形,经过低周次循环产生裂纹,由于材料自身韧性较差,裂纹迅速扩展导致断裂。因此,线夹的断裂原因为强风下导线摆动所致的低周疲劳断裂。研究结果显示,可以通过改变材料微观组织以提高其韧性和屈服强度,或通过对线夹进行结构改进,如同时加厚端子板并添加筋板来改善该问题。In order to investigate the reason for frequent fracture of aluminum terminal connector in the strong wind area in Northwest China, metallographic analysis, composition analysis, performance test and finite element analysis are carried out on the connectors, and the fatigue test is performed using a swing fatigue testing machine. The results show that the relevant properties of the materials meet the existing national standards.However, under the actual conditions in northwest, when the wind level reaches 7~8, the maximum stress exceeds the yield strength of the material, and the plastic deformation in the stress concentration area causes cracks after low cycles, the cracks propagate rapidly and cause fracture because of the poor toughness.Therefore, the reason for the fracture of the terminal connectors is the low-cycle fatigue fracture caused by the swing of the power lines under strong wind. This problem can be improved by changing the micro-structure of the material to improve the toughness and yield strength, or by improving the structure of the connectors, such as thickening the terminal board and adding ribs at the same time.

关 键 词：设备线夹 疲劳 强风 电力传输 

分 类 号：TM751[电气工程—电力系统及自动化]