摘要
该文测量并分析了不同水分和老化程度绝缘油的时频域介电响应,通过频域介电谱分析绝缘油弛豫时间较小的弛豫过程,通过极化电流分析绝缘油弛豫时间较大的弛豫过程和直流电导过程,并研究水分含量和老化程度对弛豫过程特征参数的影响。研究表明,绝缘油频域介电谱可以分为直流电导频段、弛豫极化频段和高频极化频段三个频段。直流电导频段和高频极化频段的实部恒定,虚部与频率成反比,表现为电阻特性。但两个频段的损耗机制不同,前者以电导损耗为主,由直流电导率决定;后者以极化损耗为主,由高频电导率决定。绝缘油的水分含量对直流电导率影响较大,老化程度对高频电导率影响较大。绝缘油频谱在弛豫极化频段的实部和虚部斜率随频率发生变化,表现为明显的弛豫过程。水分含量会减小绝缘油的弛豫时间,老化程度对弛豫时间影响较小。
The dielectric response in time and frequency domain of insulation oil with different water content and aging status is measured and analyzed in this paper.Analyze the relaxation process of insulating oil with shorter relaxation time based on the frequency domain dielectric spectroscopy.Analyze the relaxation process of insulating oil with longer relaxation time and DC conductance process based on the polarization current.And analyze the influence on relaxation process parameters by different water moisture and aging status.As the research shows,there are three characteristic frequency band of insulating oil:DC conductance band,relaxation polarization band and high frequency polarization band.The real part of frequency spectrum at DC conductance band and high frequency polarization band is constant,and the imaginary part is inversely proportional to the frequency,which shows the resistance characteristic.However,the insulation loss of DC conductance band is dominated by conductance loss,and is decided by DC conductivity.The insulation loss of high frequency polarization band is dominated by polarization loss,and is decided by high frequency conductivity.Moisture content has greater impact on DC conductivity of insulating oil.Aging status has greater impact on high frequency conductivity of insulating oil.The real and the gradient of imaginary part of relaxation polarization band change with frequency,which shows the typical relaxation characteristics.Moisture content reduces the relaxation time and shifts the relaxation polarization band to higher frequency.Aging status has less impact on the relaxation time of insulating oil.
作者
徐晴川
王圣康
林福昌
李化
Xu Qingchuan;Wang Shengkang;Lin Fuchang;Li Hua(State Key Laboratory of Advanced Electromagnetic Engineering and Technology Key Laboratory of Pulsed Power Technology School of Electrical and Electronic Engineering Huazhong University of Science and Technology,Wuhan 430074 China)
出处
《电工技术学报》
EI
CSCD
北大核心
2022年第9期2355-2365,共11页
Transactions of China Electrotechnical Society
关键词
绝缘油
弛豫过程
频域介电谱
极化电流
电导损耗
极化损耗
Insulating oil
relaxation process
frequency domain dielectric spectroscopy
polarization current
conductance loss
polarization loss
