降温过程中油-纸绝缘微水析出动力学过程及其对绝缘性能的影响

项目名称： 降温过程中油-纸绝缘微水析出动力学过程及其对绝缘性能的影响

项目编号： No.51207037

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 电气科学与工程学科

项目作者： 郭文敏

作者单位： 哈尔滨理工大学

项目金额： 26万元

中文摘要： 油纸绝缘是高压、超高压和特高压大型变压器的主要绝缘形式，其内部不可避免地存在微量水分，且稳态饱和微水含量强烈依赖于温度。降温过程中油内微水析出可能是油纸绝缘电力变压器低温故障的主要原因之一。因此，研究降温过程中油-纸绝缘微水析出动力学过程及其对绝缘性能的影响具有一定的科学和工程意义。本课题拟实验研究降温过程中油纸绝缘结构内不同位置处油中微水含量随温度及时间的变化规律，以及初始微水含量、降温速度、油纸比例对这一规律的影响，并根据实验结果及油纸绝缘水分扩散理论进行物理建模和仿真分析，探明降温过程中油纸绝缘微水析出的动力学机理及物理本质。同时，研究对应状态下油纸绝缘介电性能的变化规律，探索通过油纸绝缘介电性能变化表征其微水析出动力学过程的可行性。研究结果可为寒冷地区油纸绝缘设备的设计与运行维护提供理论指导与实验依据。

中文关键词： 油纸绝缘；微水；介电性能；扩散；低温

英文摘要： Oil-paper insulation is main insulation form for HV, EHV and UHV large transformer. There is inevitably a certain amount of moisture in oil-paper insulation, and saturation moisture content at steady-state is strongly dependent on temperature. The cooling process can lead to moisture precipitation from insulating oil, and the precipitation process may be one of the reasons for low-temperature failure of power transformers insulated by oil-paper. Therefore, it is of certain scientific and engineering significance to study dynamic process of moisture precipitation from oil-paper insulation and its effect on insulation properties during cooling process. The project will experimentally study the change rule of moisture content in oil on the different spatial location with temperature or time during cooling process, as well as dynamic mechanism of the rule influenced by initial moisture content in oil, cooling rate and oil-paper proportion. Based on experimental results and moisture diffusion theory of oil-paper insulation, moisture precipitation from oil is modeled and simulated to ascertain dynamic mechanism and physical nature of moisture precipitation from oil-paper insulation during cooling process. Furthermore, corresponding variation of dielectric properties of oil-paper insulation is investigated and feasibi

英文关键词： oil-paper insulation；moisture；dielectric property；diffusion；loe-temperature