变压器绕组变形与等效电参数变化对应关系研究

变压器绕组变形与等效电参数变化的对应关系对变压器绕组变形诊断精度有重要影响。通过建立变压器绕组等效电路模型,得到了绕组结构与等效电参数之间的对应关系。在此基础上,以某变压器为例,运用电磁—结构耦合有限元方法,根据弹塑性力学原理,计算了变压器绕组在短路电磁力作用下发生的塑性变形状态、应力分布及绕组的轴向和辐向位移;然后,运用能量法计算得到了不同类型和程度的绕组变形与绕组等效电路电参数之间的对应关系。研究结果可以为从等效电路参数变化的角度诊断变压器绕组变形状态提供依据,从而提高变压器绕组变形诊断精度。

Research of Corresponding Relationship Between Transformer Winding Deformation and Variation of Equivalent Electrical Parameters

The corresponding relationship between the transformer winding deformation and the variation equivalent electrical parameters has important influence on the accuracy of diagnosis of transformer winding deformation.The corresponding relationship between the winding structure and the equivalent electrical parameters is obtained by establishing the equivalent circuit model of transformer winding.On this basis,one transformer is taken as an example and the plastic deformation state,stress and the axial and radial displacement of the transformer winding under the action of short circuit electromagnetic force are calculated respectively using the electromagnetic-structure coupled finite element method,according to the elastic-plastic mechanics principle.The energy method is used to calculate the winding equivalent circuit electrical parameters of the different type and level of winding deformation,and thus the corresponding relationship between the different type and level of winding deformation and winding equivalent circuit electrical parameters is achieved.The research results can provide reference for diagnosis of deformation state of transformer winding based on the change of equivalent circuit parameters,so as to improve the diagnostic accuracy of transformer winding deformation.