电场条件下变压器油的引燃温度特性

以目前在运变压器常用的25#绝缘油为例，测试了不同温度条件下变压器油在电极针产生的电场下的点燃特性，为变压器起火机理与防治研究提供指导。试验表明，25#变压器油在电火花能量18 J、最大电场强度为6.56×10³ kV/m的针-针电极电场条件下，点燃的临界温度约为172 ℃；其引燃有爆燃和稳定燃烧2个过程，爆燃时燃烧瓶内压力最大，为510 kPa左右，其引燃过程与单一气体组分丁烷有较大差异。

Ignition temperature characteristics oftransformer oil under the influence of electric field

This paper takes the 25# insulating oil which is commonly used in current transformers as an example to test the ignition characteristics under the electric field generated by the electrode needles under different temperature conditions, and the ignition temperature characteristics of transformer oil under specified conditions are obtained, which can provide guidance for transformer fire mechanism and prevention research. The test results show that the critical temperature of ignition of the  25# insulating oil is about 172 ℃, under the condition of needle electrode electric field, with maximum electric field 6.56×10³ kV/m, and intensity spark energy 18 J. There are two ignition processes: deflagration and stable combustion. During deflagration, the maximum pressure in the combustion bottle is about 510 kPa, which is quite different from butane.