多重硫腐蚀对变压器油纸复合绝缘劣化的影响机制研究

发布时间：2018-04-25 08:47

  本文选题：变压器 + 油纸绝缘　； 参考：《华北电力大学(北京)》2017年硕士论文

【摘要】：电力变压器是电网系统中最重要的设备之一,其正常运行是电力系统安全、可靠及经济运行的重要保证。油浸式变压器是输配电设备中最常用的变压器,也是最重要和最为核心的设备之一,对保证电网安全运行具有重大意义。变压器油中存在的活性较强的硫化物与铜导线反应生成铜的硫化物,沉积在绝缘纸表面,降低绝缘纸电气性能,引发绝缘故障。目前国内外许多研究认为,二苄基二硫(Benzyl Disulfide,以下简称DBDS)是变压器绝缘油中主要的腐蚀性硫成分,此外变压器油中还含有其他多种硫成分,如硫醇、砜类、硫醚等化合物,多种硫成分的交互作用也会对变压器油纸绝缘产生影响作用,因此,研究多重硫腐蚀对油纸绝缘系统的劣化作用机理具有重要的学术价值。为研究多种腐蚀性硫化物对油纸绝缘系统老化特性的影响规律,本文对含有不同浓度DBDS和二苄基硫醚以及十二硫醇的油纸绝缘系统在140℃环境下开展加速热老化试验,定期取样,并对绝缘纸聚合度、油纸中酸值和水分等特征参量进行测量分析。研究表明:腐蚀性硫化物加速了油纸绝缘系统的老化程度;纸中酸值和油中微水含量的波动幅度、绝缘纸裂解速率、油中糠醛含量均随DBDS和十二硫醇浓度增大而增大;油中多种腐蚀性硫化物对油纸绝缘系统老化的联合作用不等于单一硫化物的线性叠加,表明油中多种腐蚀性硫化物对油纸绝缘系统的影响存在交互作用。为研究外界环境条件对多重硫腐蚀反应的影响,本文对含有不同浓度DBDS和十六硫醇以及十八硫醇的油纸绝缘系统在130℃环境下开展加速热老化试验,并设定温度及氧气对照,定期取样进行测试。研究表明:氧气浓度不同时,在多重硫腐蚀作用下,油纸绝缘老化特性变化有一定差异;硫腐蚀对老化程度的影响整体上随温度升高而增加;同时含有两种硫化物时,十六硫醇与十八硫醇协同作用对铜片腐蚀的促进作用较弱。为研究腐蚀性绝缘油中硫化物的种类和含量,本文基于气相色谱仪和硫化学发光检测器联合分析技术,建立了一种变压器油中多重硫化物定性与定量分析的方法;利用该分析方法,研究了不同类型硫醇在变压器油中的腐蚀作用。分析结果表明当变压器油中仅含一种硫醇时,老化仅生成相应硫醚;而当变压器油中含有多种硫醇时,不同硫醇会发生交联反应,生成新的硫醚。
[Abstract]:Power transformer is one of the most important equipments in power system, and its normal operation is an important guarantee for safe, reliable and economical operation of power system. Oil-immersed transformer is the most commonly used transformer in transmission and distribution equipment, and it is also one of the most important and core equipment. It is of great significance to ensure the safe operation of power grid. The active sulfide in transformer oil reacts with copper wire to form copper sulfide, which deposits on the surface of insulator paper, reduces the electrical performance of insulator paper, and causes insulation failure. At present, many studies at home and abroad believe that Benzyl Disulfide (hereinafter referred to as DBDS) is the main corrosive sulfur component in transformer insulating oil, in addition, transformer oil also contains a variety of other sulfur components, such as mercaptan, sulfone, sulfide and so on. The interaction of various sulfur components will also affect the oil-paper insulation of transformers. Therefore, it is of great academic value to study the mechanism of degradation of oil-paper insulation system caused by multi-sulfur corrosion. In order to study the effect of various corrosive sulfides on aging characteristics of oil-paper insulation system, accelerated thermal aging tests were carried out at 140 鈩，

本文编号：1800616