倾斜偏心对同步发电机转子力学特性的影响  

Impact of Inclined Eccentricity on Rotor Mechanical Characteristics of Synchronous Generators

作　　者：何玉灵[1] 徐明星 代德瑞 郑文杰[1] 李勇[1] 唐贵基[1] HE Yuling;XU Mingxing;DAI Derui;ZHENG Wenjie;LI Yong;TANG Guiji(Hebei Key Laboratory of Electric Machinery Health Maintenance and Failure Prevention,North China Electric Power University,Baoding 071003,Hebei,China)

机构地区：[1]华北电力大学河北省电力机械装备健康维护与失效预防重点实验室,河北保定071003

出　　处：《噪声与振动控制》2024年第3期88-94,共7页Noise and Vibration Control

基　　金：国家自然科学基金资助项目(52177042);河北省自然科学基金资助项目(E2020502031);中央高校基本科研业务费专项基金资助项目(2020MS114);河北省第三批青年拔尖人才支持计划资助项目([2018]-27);河北省研究生创新能力培养资助项目(CXZZBS2023149);苏州市社会发展科技创新资助项目(SS202134)。

摘　　要：气隙偏心是一种常见的发电机机械故障。已有研究主要关注正常和轴向气隙均匀偏心对转子受载和振动特性的影响,较少关注轴向气隙非均匀偏心,即转子倾斜偏心。作为补充,全面分析转子倾斜偏心状态下故障程度差异对同步发电机转子力学特性的影响。其中,转子力学特性包括转子不平衡磁拉力激励特性和振动特性。以一台5kVA的两极故障模拟发电机为研究对象,分别进行理论分析、有限元仿真计算和实验验证。结果表明:正常情况下转子不平衡磁拉力为零,转子振动频率以常规基频和定子传递的各偶次谐波为主。在转子发生倾斜偏心故障后,转子不平衡磁拉力/振动以二次谐波为主。随着偏心程度增加,转子不平衡磁拉力/振动的二次谐波幅值将增大。此外,转子不平衡磁拉力沿轴向非均匀分布,在气隙越小的位置不平衡磁拉力越大。Air gap eccentricity is a common mechanical fault in generators.Previous researches are mainly focused on the influence of normal and uniform eccentricity of axial air gap on the loading and vibration characteristic of rotors.However,rare of studies have considered the axial air gap of non-uniform eccentricity,i.e.rotor inclination eccentricity.As a supplement,this paper comprehensively analysis the effect of the degree of failure difference on rotor mechanical characteristic in synchronous generators under rotor inclination eccentricity.The rotor mechanical characteristics include rotor unbalanced magnetic pull excitation characteristics and vibration characteristics.The theoretical analysis,finite element analysis calculation and experimental verification are performed respectively for a 5 kVA double-pole fault simulated generator.It is shown that the rotor unbalanced magnetic pull is zero in normal conditions,the rotor vibration has small amplitudes and the vibration frequency is dominated by the conventional fundamental frequency and some other even-order secondary harmonics transmitted from the stator.After rotor inclination eccentricity occurs,the unbalanced magnetic pull/vibration of the rotor is dominated by the second-order harmonic.With the increase of eccentricity degree,the second-order harmonic amplitude of the unbalanced magnetic pull/vibration of the rotor will increase.In addition,the rotor unbalance magnetic pull is non-uniformly distributed along the axial direction,the smaller the air gap is,the greater the rotor unbalanced magnetic pull is.

关 键 词：振动与波 同步发电机 转子倾斜偏心 不平衡磁拉力 转子振动 力学特性 

分 类 号：TM311[电气工程—电机]