Development of a Sun Tracking System based on the Photometric Techniques

Observational sun tracking can be used in various applications, such as adjusting the orientation of solar panels in photovoltaeic plants, analysing the effect of the atmosphere in differentiating between the observed and actual direction of the sun, determining time, date and religious moments.The sun azimuth and the elevation angle measured in a topocentric coordinate system are the parameters needed for sun tracking.In this paper, a simple sun-tracking system is designed without the need for any robotic actuators.Imaging from a dark convex surface exposed by the sun and determining the sun's position by finding its hotspot is the backbone of this system's design.Here, the hotspot position is automatically detected and the sun direction is retrieved by knowing the normal reflection direction of the convex surface.The 3D modeling of the convex surface and the geometric calibration of the proposed sun tracking system will need to be performed to reach this aim.So, the desgin of a field calibration solution to find the conversion of the measurments in the local coordinate system to a topocentric coordinate system is one of the other innovative contributions of this research.The results demonstrated that the accuracy of this system in determining noon is 29.7 seconds, in retrieving the latitude of the sun 0.31 degrees, and in determining the geographic position, it is approximately half a degree.These amounts will be proper in non-precise astronomical applications and in adjusting the orientation of the solar panels.