利用直接接触换热强化聚光光伏电池的热量散失

Enhancing heat dissipation performance of concentrator solar cells by direct contact heat transfer

提出了一种将太阳电池直接浸没到绝缘液体中,利用直接接触换热实现电池高效冷却的方式。设计了小型实验装置,在辐照度约为50,70 kW/m2的条件下,研究了硅光电池组件的液浸散热特性。液浸方式下电池组件表面的对流传热系数为900 W/(m2.K),表面散热量为43.3 kW/m2,组件温度低于50℃,表明液浸散热方式可实现聚光条件下太阳电池的高效使用。液浸聚光条件下,组件开路电压随温度升高约呈线性下降,短路电流随光强增加而增加,实验后,组件开路电压没有明显变化,但短路电流产生了永久性衰减,主要为普通晶硅电池在高倍聚光条件下的使用问题。

A direct contact heat transfer mode by directly immersing solar cells in a dielectric cooling medium was proposed to achieve a low working temperature. A small experimental system was built up. The heat dissipation performance of silicon photocell modules by liquid immersing was studied when the light irradiance was about 50 and 70 kW/m2. The results show that by using liquid immersion cooling the thermal load of 43.3 kW/m2 is moved away from modules and the temperature of modules can be cooled to be less than 50 ℃. Furthermore, the convective heat transfer coefficient reaches 900 W/（ m2 ·K）, which indicates that the liquid immersing mode is effective at achieving low working temperature and a high performance. Under liquid immersing and concentrated illumination, the open-circuit voltage of modules decreases linearly with the temperature rise, while the short circuit current rises with the increase of light intensity. After liquid immersing experiments, the open-circuit voltage of modules has no obvious change, but the short circuit current attenuates permanently. The reason for this degradation is because of the common silicon cell usage under high illuminations.