基于热电类比理论的油浸式变压器绕组热行为计算模型

Thermal Behavior Calculation Model of Oil-immersed Transformer Winding Based on Thermoelectric Analogy Theory

基于热电类比理论的油浸式变压器内部绕组与油之间热行为计算模型,在分析饼间热阻对计算结果的影响后,不再采用经验公式估算热阻结果,而是经过分析油浸式变压器绕组线饼间水平油道的油流状态后,通过基于稳态热流法构建实验模型,模拟油浸式变压器绕组饼间环境,进一步得出更具优势的热点温度的组成关系,并且从实验测得热阻数据选取能够清楚显示出热点温度变化的参数,引入到分布式参数热路模型中,得到仿真结果。将仿真结果与实际运行中的变压器监测数据对比,误差达到了1.1℃。

Through based on calculation model for the thermal behavior between oil-immersed transformer’s internal windings and oil, and after analyzing influence of the thermal resistance among cakes on the calculation result, the oil flow state of the horizontal oil passage between the transformer windings was analyzed instead of applying the empirical formula to estimate the thermal resistance result;and the experimental model was constructed through the steady-state heat flow method, including simulating the oil-immersed transformer winding in the inter-cake environment to obtain the composition relationship of the hot spot temperature. The parameters of the thermal resistance data sorting can clearly show the variation of the hot spot temperature, which is introduced into the distributed parameter thermal path model to obtain simulation result. The comparison with the transformer monitoring data in actual operation shows that, the calculated maximum error can reach 1.1℃.