用"场-路"结合方法分析和计算了一台双流制机车变压器在直流供电时用作电抗器的等效电感.在直流制式下,该变压器4个高压绕组并联开路、同一铁芯柱上的2个低压绕组串联用作滤波电抗器,整个变压器呈二端口网络.从4个低压绕组在铁心回路中产生磁场的相互方向关系考虑,4个低压绕组两两串联有4种可能的接线方式,且同一接线方式下还有双边工作和单边工作情况等.文中,在用ANSYS软件分析磁场的基础上计算了四分裂式变压器8个绕组的电感矩阵;接着,根据绕组连接列写电路方程求出端口阻抗,进而得到等效电感;并考虑了4个低压绕组4种不同接法和2种不同工况下的影响;最后,根据计算结果及对有关因素影响的分析,推荐了一种较为理想的绕组连接方法,即同一铁芯柱上2个低压绕组反向串联,且使得4个低压绕组各自产生的磁场呈漏磁场分布,这种连接方式电感值的理论计算与实测基本吻合.%A double-system locomotive transformer is used as a filter reactor under DC voltage supply,and a"field-cir-cuit"combination method is used to analyze and calculate the equivalent inductances. In this mode,four high-voltage windings are connected in parallel and in open circuit,and two low-voltage windings on an iron-core limb connected in series are used as a filter reactor in the circuit,so the transformer becomes a two-port network. Considering the direction of magnetic field generated in the iron-core loop,four low-voltage windings have four possible pair-wise series connec-tions. Meanwhile,with the same connection,two circuits can work together or individually. In this paper,based on the analysis of magnetic field by using software ANSYS,an inductance matrix about eight windings of a four-split transform-er is calculated. Then,circuit equations are formulated to obtain port impedances and equivalent inductances further. Moreover,the effects of four different connections of four low-voltage windings and two kinds of working conditions are considered. Finally,according to the result of calculation and the analysis of related factors,a proper connection of windings is proposed,i.e.,two low-voltage windings on the iron-core limb are connected in opposite series in order that the magnetic field of four low-voltage windings is in a distribution of magnetic flux leakage. The theoretical values of in-ductance with this connection agree with measurement results basically.
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