组合屏蔽层对电力变压器杂散损耗的影响

摘要

大容量单相电力变压器的箱体杂散损耗影响变压器效率和可靠性.通常采用箱体内壁敷设铁磁层的方法降低损耗,但铁磁叠片边界会使箱体局部磁场增强并产生局部过热.为此提出利用铁磁和非磁性导电层的不同组合屏蔽方法,并通过有限元仿真分析箱体和屏蔽层损耗,分析结果表明在优化屏蔽层厚度条件下纯导电层表面敷设一层铁磁材料,能有效降低总杂散损耗.%Stray loss of large single-phase power transformer tank influenced its efficiency and reliability .Mag-netic material was usually attached on the inner wall of the transformer tank in order to reduce the stray loss .How-ever, the magnetic field surrounding the ferromagnetic shielding was enhanced and resulted in local overheat of the tank.Various structures of ferro-and/or non-magnetic thin-layers are proposed and modeled by 2D and 3D finite el-ement analysis ( FEA) .Simulation results showed that the stray losses could be effectively reduced by using non -magnetically metallic layer between ferromagnetic layer and tank wall with optimal shielding thickness .