汶川地震中500kV大型变压器震害机制分析  

Analysis on Seismic Failure Mechanism of 500 kV High-Power Transformer During Wenchuan Earthquake

作　　者：谢强[1] 朱瑞元[1] 屈文俊[1] 

机构地区：[1]同济大学土木工程学院,上海市杨浦区200092

出　　处：《电网技术》2011年第3期221-226,共6页Power System Technology

基　　金：国家电网公司科技项目(SGKJJSKF[2008-508]);科技部国家重点实验室基金项目(SLDRCE 10-B-01);教育部霍英东教育基金会优选资助课题(114021)~~

摘　　要：大型变压器是变电站中的重要设备之一,在历次地震中遭到严重破坏。汶川地震中,大批变压器受损严重,首先简要介绍了汶川地震中大型变压器的主要震害特征。为分析汶川地震中遭受严重破坏的某500 kV大型变压器的震害机制,建立了梁壳组合的变压器-套管系统有限元模型。在实际纪录3组汶川地震波和其他2组地震波输入下,分析该有限元模型的地震时程响应,比较了变压器-套管系统结构关键部位的地震响应。分析结果表明:大型变压器套管结构高柔,绝缘套管抗弯强度小,且变压器箱体的柔度对套管的动力响应有放大效应,这些是导致大型变压器瓷质套管损坏的主要原因。套管是变压器的地震易损构件,在变压器的抗震设计中须充分考虑套管的地震易损性。High-power transformers are one of the most important equipment in substations and they are often seriously damaged due to earthquakes. In the violent earthquake occurred on May 12 th, 2008 in Wenchuan, China, a lot of power transformers were seriously damaged. Firstly, the main earthquake damage characteristics of high-power transformers in the Wenchuan earthquake are briefly presented. To analyze the seismic failure mechanism of a certain 500kV high-power transformer that suffered serious damage during Wenchuan earthquake, a finite-elemen~ model of transformer-bushing system, in which both beam elements and shell elements are combined, is built. Under the input of three sets of ground motions recorded in Wenchuan earthquake and other two sets of ground motions, the analysis on time-history responses during earthquake is performed by the proposed model, and the seismic responses of the key components in the structure of transformer-bushing system during the earthquake are compared. Analysis results show that bushing structure of high-power transformer is flexible and the bending strength of insulation bushing is inferior, moreover the flexibility of the transformer tank can amplify the seismic responses of the bushings. Thus the high center of gravity, larger slenderness and low strength of the porcelain bushings are main reasons leading to seismic failure of high-power transformer. Bushings are vulnerable components of high-power transformers, so in the aseismatic design of high-power transformer the vulnerability of bushings during earthquake should be taken fully into account.

关 键 词：大型变压器 套管 破坏机制 放大效应 抗震性能 汶川地震 

分 类 号：TM406[电气工程—电器]