TPV系统热辐射发电模块数值分析

建立TPV系统热辐射发电模块的数理模型,通过数值模拟获得SiC辐射器分别配合GaSb和Si电池所构成的TPV系统的输出伏安特性曲线;以GaSb电池为例,分别分析SiC辐射器温度和电池温度对系统性能的影响,得出如下结论:辐射器温度升高,系统输出电能密度迅速增大,电池效率稳步提高,辐射器温度从1400 K升至1900 K,系统输出电能密度从0.67 W·cm^-2增至5.43 W·cm^-2,电池效率从16.3%上升到24.8%;电池温度升高导致系统性能下降,电池温度每升高10 K,系统输出电能密度减少约0.15 W·cm^-2,电池效率也大幅下降.最后讨论与GaSb匹配的一种选择性辐射器的辐射能量分布情况,与SiC辐射器相比,选择性辐射器可以显著减少辐射能量中的不可用部分,从而有效提高系统的性能与稳定性.

Numerical Analysis on Thermal Radiation-electricity Module in a Thermophotovoltaic System

Physical and numerical model for a thermal radiation-electricity module in a TPV (Thermophotovoltatic) system is constructed. Current/voltage characters of the system consisting of a SiC emitter and GaSb or Si PV cells are obtained. Influences of emitter and cell temperatures are analyzed for a SiC emitter with GaSb cells. As emitter temperature rises from 1 400 K to 1 900 K, system electric power density increases from 0.67 W· cm^-2 to 5.43 W· cm^-2, and cell efficiency increases from 16.3% to 24.8%. However, the rise of cell temperature causes an opposite trend. As cell temperature rises 10K, system electric power density deceases about 0.15 W· cm^-2, and the cell efficiency deceases dramatically. The radiative energy distribution of a selective emitter with GaSb cells is discussed. Unusable radiative energy of the selective emitter can be reduced remarkably compared to a SiC emitter and thus improves system performance and stability effciently.