中文摘要：

从水轮发电机偏心转子的气隙磁场能表达式入手,推导电磁刚度矩阵,分别采用八参数模型和非线性Muszynska模型模拟水轮机转轮密封,综合考虑电磁与水力密封振源,建立由三个导轴承支承的机组轴系统三维有限元模型,分析电磁参数、密封参数、导轴承刚度及大轴外径等参数对轴系临界失稳转速的影响。为水电机组的动力设计及优化运行提供参考和依据。

英文摘要：

A magnetic stiffness matrix was derived to express the energy of air-gap magnetic field of generator rotor,and an eight-parameter model and Muszynska model were used to simulate the seal effect of turbine impeller.A shaft system model was developed with consideration of the vibration sources in the magnetic field and the hydraulic seal.By adopting these models,sensitivity analysis was conducted for the responses of critical speed to various parameters of magnetic field,seal,journal stiffness and outer diameter.This study offers references for dynamic design and operation of generator set.