支撑失效对变压器绕组短路动力学特性的影响

Influence of Support Failure on Short-circuit Dynamic Characteristics of Transformer Winding

本文中作者以110kV电力变压器为例,结合理论分析和有限元方法对考虑局部支撑失效影响的变压器绕组短路动力学特性进行了数值仿真研究,建立了短路条件下的变压器绕组电磁-结构耦合动力学分析模型,并利用三维有限元方法计算了短路电流作用下漏磁场与电磁力分布。对不同垫块、撑条支撑失效情况进行了模拟,比较分析了局部支撑失效对绕组幅向和轴向振动位移特性。结果表明:支撑失效后的绕组局部线饼位移都出现了剧烈显著变化,相比正常绕组的最大振动位移增加168%,将为研究真实工况下的电力变压器绕组变形以及短路动力学关联特征提供重要参考。

In this paper,taking 110 kV power transformer as an example,the short-circuit dynamic characteristics of transformer winding considering the influence of local support failure are studied by numerical simulation combined with theoretical analysis and finite element method.The electromagnetic-structural coupling dynamic analysis model of transformer winding under short-circuit condition is established,and the leakage magnetic field and electromagnetic force distribution under short-circuit current are calculated by three-dimensional finite element method.The support failure of different spacer and support is simulated,and the amplitude and axial vibration displacement characteristics of the winding are compared and analyzed.The results show that the local wire cake displacement of the winding after the failure of the support changes significantly,and the maximum vibration displacement of the normal winding increases by 168%.The results of this paper provide an important reference for simulating the real transformer winding constraint state and the dynamic characteristics under short circuit.