Study on the optical performance of novel dish solar concentrator formed by rotating array of plane mirrors with the same size

Abstract

A novel dish concentrator formed by rotating array of same square plane mirror is proposed, which has the advantages of arrangement compact and low cost. The influence of concentrator geometric parameters on its optical performance is analyzed using ray tracing method. The geometric parameters include concentrator width D, the ratio of concentrator focal length f1 to its width D (i.e. f1/D), mirror width d. Finally, the effects of mirror slope error and tracking error on optical performance are analyzed, and the experimental verification of small concentrator is carried out. The results show that the flux distribution uniformity is improved with the increase of f1/D and d. At the best parameter is f1/D = 1.2 and d = 450 mm when D is 6 m–10 m, the focused spots are all square and flux distribution is very uniform, and flux uniformity can still maintained when mirror slope error is controlled at 2.0 mrad. With a small mirror width such as 150 mm, the obtained flux distribution presents Gaussian distribution and its max concentration ratio can reach 2963. In a word, this concentrator can be applied to concentrating photovoltaic or thermal utilization by reasonably selecting the geometric parameters.