干式变压器铜铝线材涡流检测技术开发与应用

Development and application of eddy current testing technology for copper and aluminum wire of dry transformer

干式变压器作为电网的重要设备,当前存在"线圈以铝代铜、以次充好"现象。如何快速准确鉴别批量干式变压器线圈材质,成为当前配电网关注的难题。根据干式变压器特点,结合电磁涡流检测原理,建立了以铜铝线材特征相位、线材宽度为变量的检测分析方法,并找出铜铝线材线宽与特征相位关系规律,经现场检测验证,解决了干式变压器在不破坏情况下铜铝线材鉴别难题。

As an important equipment of power grid,the dry-type transformer has the phenomenon of"replacing copper with aluminum in the coil".How to identify the coil material of batch dry transformer quickly and accurately has become a difficult problem for distribution network.according to the characteristics of dry transformer and the principle of electromagnetic eddy current detection,a detection and analysis method is established with the characteristic phase of material property of copper and aluminum coil and the width of coil wire as variables,and find out the relationship between line width and characteristic phase of copper-aluminum wire.This method is verified by field test and solve the problem of difficult identification of copper-aluminum wire of dry transformer coil without damage.