太阳能等照度带聚焦菲涅耳透镜研究

为了提高聚光发电时太阳电池的光电转换效率,从提高太阳电池表面会聚光强分布的均匀性入手,对传统平板型线聚焦透镜进行改进,提出一种用于聚光光伏发电的等照度带聚焦菲涅耳透镜设计方法。带聚焦菲涅耳透镜分为奇数个单元,每个单元宽度与太阳电池宽度相等,单元内所有尖劈角φ相等并将太阳辐射等宽度折射至太阳电池表面,从而实现各单元透过的太阳能等照度叠加。最大聚光比由光伏电池宽度、透镜与太阳电池间距以及透镜材料折射率决定。对带聚焦和线聚焦两种透镜聚光条件下电池表面温度分布情况进行比较分析,验证了等照度带聚焦透镜设计的可行性。

RESEARCH ON STRIP-FOCUS FRESNEL SOLAR CONCENTRATOR WITH REGULAR ILLUMINATION

To improve the photovoltaic(PV) conversion efficiency of solar cells under the concentrated solar radiation condition,the conventional flat style line-focus Fresnel lens should be modified to improve the illumination uniformity on the focal plane.In this study,a design method of a new strip-focus Fresnel lens was developed,which has regular concentrated illumination and can be used for solar concentrated PV system.The strip-focus Fresnel lens is divided into odd units.The angle φ of wedge in the same unit is the same with each others and every unit can refract solar radiation onto solar cells with the same width.It results in the superposition of solar radiation with regular illumination.The maximum concentrating radio of this Fresnel lens is determined by the width of solar cells,the focal length and the refractive index of the lens material.By comparing the temperature distributions on the solar cells under the concentrated solar radiation conditions of strip-focus Fresnel lens and line-focus Fresnel lens,the feasibility of the design of the strip-focus Fresnel lens is validated.