短路条件下变压器器身轴向振动的分析  

Axial vibration analysis of transformer active part under short-circuit

作　　者：李岩[1] 周伟[1] 井永腾[1] 韩芳旭[1] 

机构地区：[1]沈阳工业大学特种电机研究所,辽宁沈阳110870

出　　处：《电工电能新技术》2012年第3期49-53,共5页Advanced Technology of Electrical Engineering and Energy

基　　金：国家自然科学基金资助项目(51177103)

摘　　要：基于电力变压器绕组轴向振动的质量弹簧系统数学模型并考虑变压器绕组的轴向振动的非线性特点,简化计算模型。本文针对一台型号为DFP1-240MVA/500kV的电力变压器,建立了由铁心、绕组、垫块、夹件和拉板组成的电力变压器器身振动的仿真模型,分别计算了变压器绕组和器身在不同轴向预紧力作用下的固有频率和振动型态,得出了轴向预紧力的变化与其轴向振动固有频率变化之间的关系。同时对短路条件下绕组轴向动态短路力所产生的器身轴向振动进行了分析。分析结果表明:短路时存在以50Hz和100Hz为基频的短路力,如果变压器的固有频率接近这两种频率及其倍频,会发生谐振,使振动位移变大,降低变压器结构的稳定性。Based on the mass-spring system mathematical model for the axial vibration of power transformer winding and its nonlinear characteristics, a calculation model is reasonably simplified. In this paper, according to a DFP1- 240MVA/500kV type power transformer, a model simulation system of the vibration of a power transformer＇s active parts which compose of core, windings, spacers, tensile plates and clamp frames is established. The analysis method of power transformer active part is given, and the natural frequencies and vibration modes in different levels of axial pre-compression of active part and windings are calculated. The relations between the changes of axial precompression and axial vibration natural frequencies on transformer are investigated. Meanwhile, the active part vi- bration caused by axial dynamic short-circuit forces of windings under short-circuit conditions is analyzed. The analysis results indicate that the short-circuit force in 50Hz and 100Hz is existed and if the natural frequency of transformer is close to them and their harmonics, the resonance will happen. So, the displacement of vibration will be large, and the structure stability of transformer will be reduced.

关 键 词：电力变压器 轴向振动 器身 预紧力 固有频率 短路力 

分 类 号：TM41[电气工程—电器]