A Sun Spot Center Orientation Method Based on Ellipse Fitting in the Application of CPV Solar Tracker

As one of the most important part of the Concentrated Photovoltaic (CPV) system, the tracking accuracy and sensitivity of the solar tracker has a significant influence on the lighting rate and power generation rate of CPV system. The CPV solar tracker based on ARM tracks the sun mainly by using the CMOS sensor. In order to improve the tracking sensitivity, a method of sun spot center orientation based on canny edge operator and ellipse fitting is presented in this paper. The new method is not demanding for integrity and definition of the sun spot. After being used in the CPV solar tracker, the superiority of accuracy and applicability of the new method is proved by comparing with the traditional methods.