微小型圓型式菱鏡陣列實現第二級太陽能集光器的設計及模擬

Abstract

本篇論文主題放在太陽能集光器，包含基本知識、理論以及設計。本文開頭先從有關太陽的知識介紹起，並推廣其相關知識到太陽能電池。更甚者，為了減少太陽能電池的成本，人們利用太陽能集光器，把大面積的入射光，收集至較小區域。此種方法較以往傳統方法，直接用太陽能電池吸收光，來的更加有效率。這也是本篇論文的主軸。 在第二章，因為我們需要知道，如何計算收光效率，所以我們從最早的惠更斯定理談起，並引進其基本電磁學理論，這樣一來我們可以估算其電腦模擬的是否正確。在此章，我們也推導出基本的造鏡者公式，包含菲涅爾鏡子、拋物面鏡與球面鏡，並介紹其基本特性。 而第三章可謂本論文的核心，因為在第三章裡，不僅僅包含我們所設計的集光器- “微小型圓形式菱鏡陣列”的概念，並包含我們所驗證出的結論。因此我們可以得到在不同條件情況下，諸如：不同入射角度和不同集光器的銳角角度，其集光器的收光效率以及能量分布圖。此外，由於我們所設計出來的集光器是適用於第二集光器，因此我們拿最常見的集光器 -- 菲涅爾透鏡，當作主要集光器，並計算在不同NA值的菲涅爾集光器及不同入射的角度下，所得到的集光效率及能量分布圖。最後，我們所設計出的“微小型圓形式菱鏡陣列”具有93的聚光比及90%的集光效率。若和菲涅爾鏡子結合，則可得到810的聚光比，和92%的集光效率。

The main theme of the thesis is focus on the solar concentrator, including the basic knowledge, theory and design. At first, we start from the characteristic of sun and extend the relative knowledge to the solar cell. Furthermore, for the purpose of cost reduction, people develop solar concentrator to collect light in wider area than the area of traditional solar cell, which is illuminated directly without concentrator. In second chapter, since we have to know the theory about how to calculate power efficiency, starting from the Hungen’s theory to the fundamental electromagnetic waves theory is necessary so as to obtain the power efficiency just by handwriting. We also derive the equation for the prototype concentrator, such as Fresnel lens, parabolic concentrator and circular concentrator and introduce their characteristics, respectively. The third chapter is the kernel of this thesis, since it contains not only our idea but also the conclusions for our concentrator, called “micro circular prisms array”. Thus we can find the power efficiencies and power distributions under different conditions, such as different incident angles and bottom acute angles. Besides, since our model was fabricated for secondary concentrator, we used the common solar concentrator, Fresnel lens, as the primary concentrator and made several simulations with different variants, including NA value of Fresnel lens and incident angle. We also examine the power distribution upon the solar cell due to the reason that the solar cell needs high uniformity of incident rays so as to generate power efficiently. Finally, we can obtain the geometric concentration ratio of the secondary solar concentrator is 93 with a high efficiency of 90%, and the overall geometric concentration ratio can be 810 with an efficiency of 92%.