真实场景下换流变压器空冷换热器换热能力提升

Heat Exchange Capacity Improvement of Air-cooling Heat Exchanger of Converter Transformer in Real Scene

为保障高压直流输电换流站内换流变压器的安全稳定运行,需明确影响换流变压器空冷换热器换热能力的主要因素,并对其影响机制开展深入研究。针对某北方高压直流输电换流站内换流变压器的空冷换热器,通过数值建模与计算分析,研究了真实场景下周围墙体对空冷换热器换热能力的影响规律,提出了能够提升换热能力的技术方案。结果表明,由于降噪墙及地面的影响,下侧换热器将旁侧换热器的部分出流热风吸入,从而使得其进风温度高于环境温度,整个换热器的实际换热量比理论值低19.7%;在空冷换热器与降噪墙的间距为1.2~2.2 m、相对高度为0.2~3.0 m时,存在最优位置使空冷换热器换热效果最佳,此时换热量相对原始位置增加4.8%。

In order to ensure the safe and stable operation of the converter transformer in the high voltage direct current(HVDC)converter station,it is necessary to clarify the main factors affecting the heat transfer capacity of the air-cooled heat exchanger of the converter transformer,and conduct indepth research on its influencing mechanism.Numerical modeling and calculation analysis were carried out for the air-cooled heat exchanger of the converter transformer in a northern HVDC converter station.The influence of the surrounding walls on the heat transfer capacity of the air-cooled heat exchanger in the real scene was studied,and a technical scheme that can improve the heat transfer capacity was proposed.The results show that the lower side heat exchanger absorbs part of the hot air from the side heat exchanger due to the influence of the noise reduction wall and the ground,which makes the inlet air temperature higher than the ambient temperature.The actual heat transfer of the whole heat exchanger is 19.7%lower than the theoretical value.When the distance between the air-cooled heat exchanger and the noise reduction wall is 1.2~2.2 m and the relative height is 0.2~3.0 m,the optimal position exists for the best heat transfer effect of the air-cooled heat exchanger,and the heat transfer rate increases by 4.8%relative to the original position.