风冷式电力变压器散热计算的探讨

根据散热计算,合理选用冷却风速,是变压器风机选型和节能降噪改造的关键。本文按照竖直平板大空问自然对流和外掠平板强制对流,计算了50 MVA变压器的换热量,并根据变压器的损耗,修正了Nu数,确定了冷却风速,由此开发的低噪声轴流风机,经过在西安供电局110 kV雁塔变电站1号主变压器试运行,达到了散热和降噪的目的。

Discussion on Heat Dissipation Calculation of the Air-cooled Power Transformer

Selecting a reasonable cooling air velocity according to the heat dissipation calculation is the key point to the energy saving and noise reduction of the transformer fans. The heat exchange of 50MVA transformer is calculated on basis of vertical flat natured convection and forced convection models. Based on the power transformer loss, it corrects Nu and ensures the cooling air velocity. Thus, a low noise axial fan is developed. After the trial running on No.1 main transformer of 1 10kV Yanta Station, Xi an Power Supply Bureau, the goal of heat diffusion and noise reduction is achieved.