传热能力对光伏电池特性的影响

发布时间：2018-06-18 06:58

本文选题：光伏电池 + 温差发电模块　；参考：《重庆大学》2014年硕士论文

【摘要】：随着节能减排、可持续发展等观念的深入人心，光伏发电作为一种清洁环保的发电方式越来越受到人们的关注。光伏发电的核心元件是光伏电池，然而工作温度却制约了光伏电池的发电效率。研究表明：温度每升高1C，开路电压降低0.4%，短路电流升高0.25%，光伏电池的最大输出功率降低0.06%。本文从传热的角度出发，采用模拟与实验相结合的方式来研究进入系统热流密度、系统与外界换热情况以及接触热阻等因素对光伏电池温度分布和发电性能的影响。研究表明：光伏发电系统与外界换热能力的大小直接影响到光伏电池的温度，进而影响到发电效率。考虑进入系统内部的热流密度为1376W/m2，采用空气自然对流方式换热(对应Nu数为14.98)，光伏电池的发电效率可达17.6%。若采用强制对流或水冷方式等强化措施换热则可降低光伏电池的温度，提高发电效率，当Nu数达到1500时，光伏电池的发电效率最大可达到21%。若在光伏电池底部加入温差发电模块，组成光伏-温差混合系统，同样进入混合系统内部的热流密度为1376W/m2，采用空气自然对流方式换热(对应Nu数为14.98)，，混合系统中光伏电池的发电效率可增加到19.37%。温差发电模块的加入使光伏电池的温度降低8.3%，发电效率增加10.1%。若混合系统与外界换热的Nu数大于1500，则光伏电池和温差发电模块的发电效率几乎与Nu数的变化无关。在研究系统传热特性时发现，接触热阻在很大程度上制约了接触面间的热量传递，因此温差模块与光伏电池之间接触方式的选择尤为重要。通过对比不同接触形式发现，本文提出的侧壁过盈接触方式相比于直接接触和导热硅胶接触方式能够有效的降低接触热阻，强化传热。
[Abstract]:With the concept of energy saving and emission reduction, sustainable development and so on, photovoltaic power generation as a clean and environmentally friendly power generation has attracted more and more attention. The core component of photovoltaic power generation is photovoltaic cells, but the working temperature restricts the efficiency of photovoltaic cells. The results show that the open-circuit voltage decreases 0.4, the short-circuit current increases 0.25 and the maximum output power of photovoltaic cells decreases 0.06 for each temperature rise of 1C. From the point of view of heat transfer, the effects of heat flux, heat transfer between the system and the outside world and contact thermal resistance on the temperature distribution and generation performance of photovoltaic cells are studied by combining simulation and experiment. The results show that the heat transfer capacity of photovoltaic system and the outside world directly affect the temperature of photovoltaic cell and then affect the efficiency of power generation. The heat flux entering the system is 1376W / m ~ 2, and the natural convection heat transfer is adopted (corresponding to the Nu number is 14.98), the efficiency of photovoltaic cell can reach 17.6g / m ~ (2). If forced convection or water cooling is used to heat transfer, the temperature of photovoltaic cell can be reduced and the efficiency of power generation can be improved. When the number of Nu reaches 1500, the maximum efficiency of photovoltaic cell can reach 21. If a thermoelectricity module is added to the bottom of a photovoltaic cell, a hybrid photovoltaic / temperature differential system is formed. The heat flux entering the hybrid system is 1376 W / m ~ 2, and the heat transfer by natural air convection (corresponding to the Nu number is 14.98), the efficiency of photovoltaic cells in the hybrid system can be increased to 19.37. With the addition of thermoelectric module, the temperature of photovoltaic cell is decreased by 8.3, and the efficiency of power generation is increased by 10.1. If the Nu number of heat transfer between the hybrid system and the outside world is greater than 1500, the generation efficiency of photovoltaic cells and thermoelectric modules is almost independent of the variation of Nu number. When studying the heat transfer characteristics of the system, it is found that the contact thermal resistance restricts the heat transfer between the contact surfaces to a great extent, so the choice of the contact mode between the temperature difference module and the photovoltaic cell is particularly important. By comparing the different contact forms, it is found that the lateral wall interference contact mode can effectively reduce the contact thermal resistance and enhance the heat transfer compared with the direct contact and thermal conductive silica gel contact mode.
【学位授予单位】：重庆大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM914

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