环氧绝缘干式变压器线圈固化过程温度场仿真研究

为了防止生产过程中干式变压器树脂线圈的开裂、缩孔、白斑等问题,笔者研究了产生开裂等缺陷的形成内因,并根据于式变压器线圈材料性能随温度变化的特性,采用非线性分析建立了线圈浇注、固化、冷却过程瞬态温度场、热应力场三维有限元模型,并确定温度场中初始条件、边界条件,设计了一种有效模拟干式变压器浇注、固化、冷却过程中三维温度场和应力场分布的方法模拟其内部分布,从而改进干式变压器的工艺参数和性能并减少开裂等缺陷的产生。实验表明该仿真能够较好地再现线圈固化过程中的温度场和应力场分布。

Numerical Simulation of Temperature Field in Curing Process for Epoxy Resin Dry-type Transformer Winding

In order to avoid crack faults and shrinkage of winding due to the changes in temperature field and stress field during the production process,a study was put up.By analyzing the reasons for forming faults and considering the performance of the winding material changing with temperature,the nonlinear analysis was adopted to build a 3-D finite element analysis model of transient temperature field and thermal-stress field during casting,curing,and cooling process of the dry-type transformer winding.The initial condition,boundary condition,and latent heat were then determined,thus the model could be applied in simulation of temperature and stress fields distribution in that process.The experimental results indicate that the numerical simulation coincide well with the actual dynamic changes of temperature and stress fields in casting,curing and cooling process of epoxy resin dry-type transformer winding,which will benefit the improvement of transformer performance and the reduction of cracks.