基于有限元法的大型电力变压器抗短路能力分析

Analyzing the Short-cinuit Withstanding Ability of Large Power Transformer Based the FEM Method

为验证基于有限元法的变压器抗短路能力计算方法的有效性,通过开展变压器基于磁场有限元方法的计算分析,并进行了突发短路试验的220 kV变压器的试验结果和计算结果对比,以及因输电线路短路导致故障的500 kV变压器实际受损部位与计算分析结果对比.由通过了突发短路试验的新变压器与在运变压器的数据对比,分析了变压器低压线圈辐向宽度、所用电磁线尺寸、撑条以及电磁线Rp0 2对变压器抗短路能力的影响.结果表明：通过变压器短路试验的产品在低压线圈辐向宽度增加了10％～22％,其电磁线的子导线尺寸增加了35％～50％.通过此项研究,验证了该分析方法关于绕组机械强度分析的有效性,为新采购变压器的抗短路能力分析评估提供了手段.

A calculation method of ability to withstand short circuit of large power transformer based on finite elementmethod （FEM） is verified by comparing results of 220 kV power transformer short-circuit test and calculation results, andby analyzing 500 kV power transformer fault place due to transmission line＇s short circuit and calculation analy-sis.Meanwhile, the relationship inner winding width, wire radial size, spacers, wire yield strength Rpo.2 with ability towithstand short circuit of large power transformer is analyzed by comparing data about operating transformer and newtransformer which pass short-circuit test. Inner winding width is increased by about 10%-22%, and wire radial size is in-creased by about 35%-50%. It is validated that the finite element method of ability to withstand short circuit of largepower transformer can be used to analyze mechanical strength of transformer＇s winding, which provides ability to with-stand short circuit of new procurement transformer.