考虑液-固耦合的大型超高压换流变压器地震响应研究

针对大型超高压换流变压器的地震响应问题,以一超高压±800kV换流变压器为研究对象,考虑其本体中油与箱壁的相互作用建立三维有限元分析模型,采用LS-DYNA分析换流变压器的自振特性、地震作用下的动力响应规律以及换流变压器的薄弱部位。研究结果显示,对于大型超高压换流变压器,本体中油与箱壁的相互作用对结构动力响应有一定的放大作用,进行自振特性和地震响应分析时应考虑;套管体系的薄弱部位为套管的底部和中间部位,在这两个位置拉应力和压应力最大值交替出现;换流变套管体系在地震作用下的位移较大,套管顶部的导线应设置足够大的伸缩距离。

Study on the Seismic Response Study of a Converter Transformer Considering Oil-solid Interaction

With the aim of carrying out a dynamic response study of a large, ultrahigh voltage converter transformer, the 3D FEM analysis model of an actual ±800 kV converter transformer was built considering oil-solid interaction. Then, the natural vibration characteristics, dynamic response rules, and vulnerable points of the ±800 kV converter transformer were analyzed by using the LS-DYNA software. Simulation results show that interaction of the oil and wall has an obvious amplification effect on the dynamic response of the converter transformer, and that the oil-solid interaction should be considered in the analysis of natural vibration characteristics and seismic response of a converter transformer. The vulnerable points of the sleeve are at the root and middle part of the sleeve, and the max tensile and press stress at these points appear in turn. The sleeves of the converter transformer show large displacement during an earthquake. In addition, the electric wire at the top of the sleeve should have enough reserved length.