覆冰特高压导线风致动张力试验与分析  

Experiment and Analysis on Wind-induced Dynamic Tension of Ice Covered UHV Conductors

作　　者：谢强[1] 严承涌 张勇[3] 

机构地区：[1]同济大学建筑工程系,上海200092 [2]中国海诚工程科技股份有限公司,上海200031 [3]华东电网有限公司,上海200002

出　　处：《高电压技术》2010年第8期1865-1870,共6页High Voltage Engineering

基　　金：国家自然科学基金(50508026;50778135);教育部霍英东教育基金会优选资助课题(114021);国家电网公司科技项目(2008-536)~~

摘　　要：覆冰导线在低风速作用下的风致振动现象是一个复杂问题,而导线动张力的计算对于输电铁塔的抗冰设计具有重要的参考意义。为研究风荷载下覆冰导线动张力对输电塔结构的动力作用,利用光纤布拉格光栅传感器,通过覆冰特高压输电塔-8分裂导线耦联体系风洞试验测得了导线的动应变,验证了导线动张力模型的有效性。用动张力模型计算结果和我国重冰线路设计规程中导线的荷载标准值进行了比较,发现规范对覆冰导线弦向张力荷载值的考虑略显不足,不平衡张力容易成为输电塔结构破坏的重要原因。对覆冰导线的动张力试验和分析研究结果表明:随着覆冰厚度的增加,导线自振频率降低,非线性增强,导线端部动张力增幅明显。考虑风荷载与冰荷载的组合后,覆冰输电塔的安全设计需要进一步提高。Vibration of ice covered conductors under low speed wind is a complex problem. It is important to calculate the wind induced dynamic tension of ice covered conductors for the ice resistant design of transmission towers. By using fiber Bragg grating （FBG） sensors, the dynamic strains of the conductors were measured in the wind tunnel test on a simulated ice covered UHV transmission tower-eight bundled conductors coupling system. Validity of the conductor dynamic tension model was verified in the test. The calculation results of the dynamic tension model were compared with those obtained according to the current design code. The results of the dynamic strain of the ice covered conductor measured in the wind tunnel test and calculated analytically show that ,with the increase of the ice thickness, the natural frequencies of the conductors become lower and the nonlinearity of the conductor becomes severe. Especially, the dynamic tension of the conductor end remarkably increases. The chord wise tension load of ice covered conductor calculated by the design code is slightly less than that of the theoretical model. The unequal tension on transmission towers caused by the ice covered conductors will become one of the major causes for possible structural failures.

关 键 词：覆冰导线 动张力 光纤布拉格光栅(FBG) 输电塔线耦联体系 风洞试验 风致振动 荷载组合 

分 类 号：TM751[电气工程—电力系统及自动化]