Solar tracker system based on a Digital Heuristic Controller

This paper proposes a sun tracking system based on a Digital Heuristic Controller. The sun tracking device detects the differences in luminosity between a central reference sensor and four other sensors, which surround the first one in the quadrants of a shadow generating wall. This wall has the shape of a cross so as to generate shadows over the sensors, which are not directly exposed to sunlight. The central reference is located on the central/superior part of the wall, so as to rid it from the shadow generated by the wall itself and detect the maximum luminosity in the environment. An analogical/digital converter perceives the differences in luminosity between the reference sensor and each one of the other sensors and sends a signal to the digital controller installed in a PC which activates, under a programmable frequency, a rotating device built with a steppers motors with two degrees of freedom. This device orients the plane which holds the solar pane and the four sensors, locating the platform perpendicularly to the sun rays; then, if the rays alter their orientation, the tracking device follows the angular trajectory of the sun's position. A solar sensor prototype with a meter has been built and tested and a significant increase of solar radiation has been detected, if compared with a sensor in a fixed positions, which is the case of the static or fixed solar panels.