水分对大型汽轮发电机定子线棒主绝缘FDS测试的影响研究  

Effect of Moisture on Frequency Domain Spectroscopy Test of Stator Insulation for Large Turbine-Generator

作　　者：张征平 尹小兵[2] 涂小涛 郝长金 冉旺 王兵[2] 

机构地区：[1]广东电网有限责任公司电力科学研究院,广州510080 [2]西南交通大学电气工程学院,成都610031

出　　处：《绝缘材料》2016年第6期45-50,共6页Insulating Materials

摘　　要：为更好的将频域介电谱技术(FDS)应用于发电机主绝缘状态的评估,通过实验得到不同水分含量的线棒试样,对其工频介质损耗因数tanδ、电容C以及FDS进行测试,研究水分对频域介电谱的影响。结果表明:随着线棒干燥周期的增加(水分含量减小),工频介质损耗tanδ、电容C呈指数规律下降;电机线棒的介质损耗因数tanδ、复介电常数虚部ε″随FDS测试电场频率增加整体呈下降趋势,但下降过程中会在部分频段出现弛豫峰;而复介电常数实部ε′随FDS测试电场频率增加而不断下降。不同水分状态下tanδ弛豫峰值及对应频率fmax随线棒干燥周期增加呈指数规律下降,介损弛豫峰值和fmax与线棒水分关系密切,能反映电机线棒绝缘中的水分含量。To better apply frequency domain dielectric spectroscopy （FDS） technology in assessment of the stator insulation condition of generator, the stator bar samples with different moisture were prepared, and then the dielectric loss factor （tanδ） and capacitance （C） in power frequency and the FDS were mea-sured to study the effect of moisture on the frequency domain dielectric spectroscopy. The results show that with the increase of the drying cycles of stator bar samples （moisture content decrease）, the tanδand C in power frequency decrease exponentially. The tanδ and ε″ of the stator bars decrease with the increase of electric field frequency in the FDS test, but there is a relaxation peak in some frequency band during the decline process, while the ε′ continuously decreases with the increase of electric field fre-quency. The relaxation peak of tanδ and corresponding frequency （fmax） decrease exponentially with the increase of drying cycles, the relaxation peak of tanδ and fmax have close relationship with the moisture of stator bars, and they can reflect the moisture content of stator insulation.

关 键 词：汽轮发电机 主绝缘 水分 频域介电谱 介损弛豫峰 

分 类 号：TM855[电气工程—高电压与绝缘技术] TM311