油浸式变压器绝缘纸对绕组温度的影响

油浸式变压器中的绕组绝缘纸是绝缘系统重要的组成部分,是一种热的不良导体,均匀的外包住绕组并浸泡于变压器油中,对绕组与变压器油之间的热量传递有很大的阻隔效果,导致绕组无法有效散热.本文运用有限元法,建立自然油循环式变压器绕组区域温度场与流场的耦合传热模型,分析绕组在绝缘纸外包时的温度分布,研究不同厚度绝缘纸对绕组温度的影响,并通过光纤温度传感器直接测量绕组温度的实验验证仿真结果.通过对比实验结果与仿真结果,以实际厚度绕组绝缘纸进行仿真计算得到的结果与温升实验结果最大误差在1 K以内,而忽略绕组绝缘纸的仿真结果与温升实验结果存在最小1.2 K最大2 K的误差.由其他不同厚度绕组绝缘纸的仿真结果可知,绕组热点温度随着绝缘纸厚度增加而升高.

Influence of Oil-Immersed Transformer Insulation Paper on Winding Temperature

The winding insulation paper in the oil-immersed transformer is a vital component of the insulation sys-tem.It evenly wrapped insulation paper outside winding and immersed in the transformer oil has a significant barri-er effect on the heat transfer between the winding and the transformer oil,resulting in the winding being unable to dissipate heat effectively.In this paper,through the Finite Element Method (FEM),a coupled heat transfer model of the natural oil circulation transformer winding area is established,which couples the temperature field and flow field.This model is used to analyze the temperature distribution of the winding when the winding is wrapped with insulation paper.Moreover,the winding temperature wrapped with different thickness insulation paper is studied. The simulation results are verified by the experiments,in which the winding temperature is directly measured by optical fiber temperature sensors.By comparing the experimental results with the simulation results,the maximum error between the simulation result and the experiment result is within 1 K when considering the insulating paper, while the minimum error is 1 .2 K and the maximum error is 2 K when the insulation paper is neglected in the simu-lation.From the simulation results of winding insulation paper of different thicknesses,it can be seen that the winding hot spot temperature increases with the increase of the thickness of the insulation paper.