汽轮发电机定子绕组端部振动模态分析

Vibration Modal Analysis of Stator End Winding of a Turbo-generator

结构振动问题在大型汽轮发电机中普遍存在,尤其定子端部绕组的振动问题最为突出。定子绕组端部的振动模态分析是减小端部振动的有效手段。利用三维有限元法模态分析,通过比较、分析发电机定子绕组端部振动系统的固有频率在不同模型结构和绕组安装工艺条件下的变化,总结出线棒的截面结构和加固结构对电机固有频率的影响规律。通过比较完整系统的模态分析计算结果和实测结果,证实了模态分析计算的有效性。分析结果对定子绕组端部结构设计和安装工艺有很大指导意义。

There usually exists the problem of structural vibration in large turbo-generators, especially the vibration ofthe stator end winding. In this paper, modal analysis of the stator end winding is done. Three- dimensional finite elementmodel for the stator end winding system is established and its natural frequencies and the corresponding modals areobtained. Then, the natural frequencies of the system with different structure and winding assembly process are analyzed andcompared. The influence of the cross- section of the winding bar and the reinforcement of the structure on the naturalfrequencies is summarized. The validity of modal analysis is proved by comparing the results of the modal analysis with themeasured results of a complete structure. The research work is helpful for design and assembly of the stator end winding.