考虑绕组间全电容参数的牵引变压器频率响应建模

Modeling of Frequency Response of Traction Transformer Considering Full Capacitance Parameters of Windings

短路故障是牵引供电系统最易遭受的故障之一,短路电流冲击极易导致牵引变压器绕组变形。频率响应分析法是目前诊断变压器绕组变形非常有效的方法之一,基于牵引变压器建立精准频率响应模型对绕组的故障诊断具有重大的参考意义。为此以一台QYS-R-(31500+25000)/220牵引变压器为研究对象,提出一种基于集总参数电路的考虑绕组间全电容参数的改进型频率响应模型,结合数值公式法和有限元法,计算得到模型相关参数,最后通过状态空间方程,仿真得到变压器频响曲线。通过与实测曲线的对比,验证了考虑绕组间全电容参数的改进型频率响应模型较传统模型准确度更高。

Short circuit fault is one of the faults the traction power supply system is most vulnerable to.Short circuit current impact is likely to cause the deformation of the traction transformer winding.Frequency response analysis is one of the most effective methods to diagnose the winding deformation of transformer.It is of great reference significance to the fault diagnosis of winding by setting up an accurate frequency response model for traction transformer.In this paper,an improved frequency response model considering full capacitance parameters of windings was proposed based on lumped parameter circuit,and the study of the QYS-R-(31500+25000)/220 traction transformer.Combined with the numerical formula and the finite element method,the parameters in the model were calculated.Finally,the frequency response curve of the transformer was obtained by the state space equation.Compared with the measured curves,the improved frequency response model considering the parameters of full capacitance between windings is more accurate than the traditional model.