热光伏系统中透明导电氧化物滤波器的优化分析

Analysis and Optimization of the Optical Filter Made from Transparent Conducting Oxides in Thermophotovoltaic System

建立了透明导电氧化物（TCOs）滤波器的理论模型，分析了载流子浓度和迁移率对其光学性能的影响。计算了TCOs滤波器应用于以GaSb电池为转换器的热光伏（TPV）系统的最佳载流子浓度和薄膜厚度，最后讨论了石英玻璃衬底厚度的影响。得出以下结论：辐射器温度为1400～1600K时，匹配Al2O3／Er3Al5O12熔融陶瓷选择性辐射器的TCOs滤波器的最优载流子浓度、薄膜厚度区间分别为（4．3～4．4）×10^20 cm^-3、389～399nm，而匹配SiC灰体辐射器的则为（4．4～4．6）×10^20 cm^-3、382～383nm；石英玻璃衬底的厚度对TCOs滤波器性能的影响很小，可以忽略。辐射器温度为1500K时，Al2O3／Er3Al5O12选择性辐射器／TCOS滤波器／GaSh电池的TPV系统输出电功率密度为0．38w／cm^2，光谱效率和TPV效率分别为56．6％和16．7％．

The model of the optical filter made from transparent conducting oxides（TCOs） was constructed and the influence of the carrier concentration as well as the mobility on the spectral properties was analyzed. The optimal carrier concentration and the film thickness were calculated for the TCOs filter applied to the thermophotovoltaic （TPV） system which takes GaSb cell as the converter, the influence of the thickness of quartz substrate on the filter performance was also discussed. The following results are obtained： when the radiator temperature varies from 1 400K to 1 600 K, the optimal carrier concentration is between （4.3--4.4）×10^20 cm^-3 and film thickness is between 389--399 nm for Al2O3/Er3Al5O12 eutectic ceramic selective radiator, while （4.4--4.6）×10^20 cm^-3 and 382--383 nm for SiC graybody radiator; the thickness of quartz substrate has little influence on the performance of TCOs filter, thus its influence can be neglected; the output electric power density is 0.38 W/cm^2, the spectral efficiency is 56.6% and TPV efficiency is 16.7% at a radiator temperature of 1 500 K for TPV system composed of Al2O3/Er3Al5O12 eutectic ceramic selective radiator, TCOs filter and GaSb cell.