摘要
分析了汽轮发电机在正常运行、气隙静态偏心故障、定子匝间短路故障、气隙静态偏心与定子匝间短路复合故障下的定子径向振动特性,以及各故障参数发展对定子振动特性的影响。首先对各情况下的气隙磁密进行了推导,得到引发定子振动的单位面积磁拉力表达式。然后分析了复合故障下定子径向振动特性及其与对应故障参数的变化关系。最后实测了SDF-9型故障模拟发电机的定子振动数据,结果与理论分析基本吻合。研究表明,正常情况和气隙静态偏心故障下发电机定子只有二倍频振动,但静偏心对应的二倍频振动幅值较正常情况要大;定子短路故障与复合故障下发电机定子都将产生二倍频、四倍频与六倍频径向振动,但复合故障所对应的振动幅值较大;复合故障下随着定子短路或气隙静态偏心程度的加剧,定子径向变形趋势及二倍频、四倍频与六倍频振动幅值均将增大;随着电机励磁电流的增大,定子径向变形趋势及二倍频、四倍频振动将增大,而六倍频振动则基本不变。
This paper analyzes the radial stator vibration characteristics and the effect of the fault parameters on the vibration characteristics under normal condition,the static air-gap eccentricity fault,the stator interturn short circuit fault,and the static air-gap eccentricity ＆ stator interturn short circuit composite faults respectively.The magnetic flux density is firstly deduced,based on which the magnetic pull per unit area （MPUA） on the stator is obtained.Then the radial stator vibration characteristics and the developing trend between the fault parameters and the vibration amplitudes are investigated.Finally,the experiment is conducted on a SDF-9 simulating generator to verify the theoretical analysis.It is shown that the stator has only 2nd harmonic vibration under the normal condition and the static air-gap eccentricity fault,in which the static air-gap eccentricity fault has larger amplitudes.When under the stator interturn short circuit fault and the composite faults,the 2nd,4th,and 6th harmonic vibrations will be induced,and the vibration amplitudes of the composite faults are larger.Besides,the development of the interturn short circuit or the static eccentricity will make the deformation trend and the vibration amplitudes increasing.The increment of the exciting current will promote the deformation trend,increase the 2nd and 4th harmonic vibration amplitudes but meanwhile keep the 6th harmonic vibration amplitude stable.
出处
《振动工程学报》
EI
CSCD
北大核心
2014年第1期118-127,共10页
Journal of Vibration Engineering
基金
中央高校基本科研业务费专项资金资助项目(13QN49)
河北省自然科学基金资助项目(E2011502024)
国家自然科学基金资助项目(51307058
51177046
51107039)
关键词
故障诊断
汽轮发电机
气隙静态偏心
定子匝间短路
定子振动
fault diagnosis
turbo-generator
static air-gap eccentricity
stator interturn short circuit
stator vibration
