评估变压器油纸绝缘受潮的电压响应方法研究  

Study on voltage response method for evaluating moisture status of transformer oil-paper insulation

作　　者：张涛[1,2] 钟婷婷[2] 张斌 李林多 肖霞 Zhang Tao;Zhong Tingting;Zhang Bin;Li Linduo;Xiao Xia(Hubei Provincial Research Center on Micro-grid Engineering Technology,China Three Gorges University, Yichang 443002, Hubei,China;College of Electrical Engineering and New Energy,China Three Gorges University, Yichang 443002, Hubei,China;State Grid Laiwu Power Supply Company, Laiwu 271100, Shandong,China)

机构地区：[1]三峡大学湖北省微电网工程技术研究中心,湖北宜昌443002 [2]三峡大学电气与新能源学院,湖北宜昌443002 [3]国网莱芜供电公司,山东莱芜271100

出　　处：《电测与仪表》2019年第9期38-42,共5页Electrical Measurement & Instrumentation

基　　金：国家自然科学基金资助项目(51307097)

摘　　要：回复电压法能有效诊断变压器油纸绝缘的状态,但测量时间过长,由此提出通过单次加压建立的极化在不同去极化时间段内的电压响应特性进行绝缘诊断的方法,省去多次加压的过程,节省了测量时间;实验研究了不同受潮状态的变压器油纸绝缘介质在不同去极化时间段的电压响应特性,结果表明,充电2 000 s后首次放电0. 1 s的电压响应初始斜率随绝缘受潮程度的增加而增大,可作为评估其受潮状态的特征量;同时通过频域分析仪测得介质的直流电导率,将其与根据首次放电初始斜率计算获得的极化电导率进行对比分析,进一步验证了该特征量的有效性。文中提出的测量方法为应用电压响应法现场快速诊断变压器油纸绝缘的受潮状态提供了一种新的研究思路。The recovery voltage measurement method can effectively evaluate the state of transformer oil-paper insulation, but the measurement time is too long. Thus, this paper presents a method to diagnose the insulation state by the voltage response characteristics of the polarization established at one polarization time and released in different depolarization periods, which eliminates the need for multiple voltage applications, and saves the time of measurement. The characteristics of response voltage in different depolarization periods of transformer oil-paper insulation under different moisture conditions were experimentally studied. The results show that the initial slope of the voltage response obtained by the first discharge 0.1 s after charging 2 000 s increases with the increase of the moisture content of the insulation, which can be used as a feature to evaluate the moisture condition of the insulation. Meanwhile, the DC conductivity of the medium was measured by the frequency domain analyzer and compared with the polarization conductivity calculated from the initial slope of the first discharge to further prove the validity of the feature. This measurement method provides a new research idea for the use of response voltage measurement to quickly diagnose the moisture status of transformer oil-paper insulation.

关 键 词：油纸绝缘 电压响应法 初始斜率 极化电导率 受潮状态 

分 类 号：TM855[电气工程—高电压与绝缘技术]