An energy transfer model of a thermophotovoltaic (TPV) system, considering the variation of GaSb cell parameters under the near-field thermal radiation, was constructed. The effects of emitter–cell distances with different cooling systems on cell parameters and TPV system performances were analyzed. The results show that if the cell temperature is set at 300 K, the required convective heat transfer coefficient of the cooling system should be as high as 8.1 × 105 W/(m2·K), which is a severe requirement for the existing cooling system. As the cell temperature increases, the photocurrent density decreases, because the internal quantum efficiency decreases due to the decreasing carrier life. The photocurrent density is significantly affected by the emitter–cell distance, because the distance has a strong impact on the thermal radiation. Similarly, the open-circuit voltage decreases with the increasing cell temperature and emitter–cell distance. To ensure a safe operation, the extreme emitter–cell distance is 12 nm for the best cooling system. When the emitter–cell distance decreases from 100 nm to 12 nm, the cell efficiency, which is around 0.25 at the far-field condition, decreases under the near-field thermal radiation, decreasing the TPV system efficiency which is obviously lower than that compared with the cell temperature of 300 K. Thus, the system performances with the cell temperature set at 300 K are overestimated. The results reveal that the variation of cell temperature needs to be considered to actually evaluate the performance of the near-field TPV system, and highly efficient cooling systems are urgently needed for the near-field TPV system.

中文翻译：

---

GaSb电池及热光伏系统在近场热辐射下的性能分析

考虑近场热辐射下GaSb电池参数的变化，构建了热光伏（TPV）系统的能量传递模型。分析了具有不同冷却系统的发射器-电池距离对电池参数和 TPV 系统性能的影响。结果表明，如果电池温度设置为 300 K，则冷却系统所需的对流传热系数应高达 8.1 × 105 W/(m2·K)，这对现有冷却系统提出了苛刻的要求. 随着电池温度升高，光电流密度降低，因为载流子寿命降低导致内部量子效率降低。光电流密度受发射极-电池距离的显着影响，因为距离对热辐射有很强的影响。相似地，开路电压随着电池温度和发射极-电池距离的增加而降低。为确保安全操作，最佳冷却系统的极端发射极-电池距离为 12 nm。当发射极-电池距离从 100 nm 减小到 12 nm 时，远场条件下电池效率约为 0.25，在近场热辐射下降低，使 TPV 系统效率降低，明显低于相比电池温度为 300 K。因此，电池温度设置为 300 K 时的系统性能被高估了。结果表明，实际评估近场TPV系统的性能需要考虑电池温度的变化，近场TPV系统迫切需要高效的冷却系统。