电力变压器附加损耗计算及影响因素分析

为了准确计算并抑制变压器的附加损耗,笔者提出了计算电力变压器附加损耗的涡流场分析方法,对两种型号的油浸式变压器的涡流以及附加损耗分布进行了计算。在涡流场的计算中,通过对铁心材料磁导率和电导率各向异性的处理来等效铁心片之间的叠积效果。文中给出了各主要金属构件中的涡流以及涡流损耗的分布,并对影响附加损耗的几个因素进行了分析。结果表明:结构件采用非导磁材料;适当的调整各结构件之间的尺寸以及采用中部出线的分接类型都可以有效地降低附加损耗。最后,对多种型号的变压器附加损耗进行了试验验证,计算与试验数据吻合很好。

Calculation and Analysis of Additional Loss in Power Transformer

This paper presents an eddy current field calculation method of additional loss in transformer based on 3D finite element analysis in order to accurately calculate and control the additional loss.The distributions of eddy current and additional loss in a transformer were calculated.In the calculation of eddy current field,the permeability and conductivity of core material were disposed to be anisotropic to equivalent to the lamination effect of core plates.In the post-processing of leakage field,the distributions of eddy current and eddy current loss were gained,and several factors that affect additional loss were studied.The result shows that additional loss can be effectively reduced by taking non-magnetic materials as structure,adjusting the distance among structures,and using the tapping type of middle wiring.Furthermore,the additional losses of various types of transformers were tested,and the calculation results agreed well with the experimental data.