Abstract

The photo voltaic cell, which converts the solar energy to a more convenient form, has been given a due focus in the recent years. Its performance could be boosted by making it to track the sun. But such a tracking system should be less expensive and simple to operate. A method to track the sun discontinuously with in a certain deviation angle has been developed and tested. A simple electro-hydraulic on-off control system was used on a Photo Voltaic panel to make it track the sun. The system is basically an uniaxial tracker with the other axis to be manually adjusted. It has an electronic eye to detect the sun. allied driver circuitry and an automated hydraulic valve and ram assembly, tilting the P.V. panel to track the sun. The sun seeker or the electronic eye was tested for its response characteristics to track the sun with a least poiting error. Similarly the weight added on the solar panel to improve the hydraulic response of the control system, was also optimised to give the best performance. The tracking system was set to track the sun East West, with the second axis tilted at 35 deg North South on December 10 and compared with a similar panel set without the tracking system. Both the panels were electrically loaded and their energy output characteristics were recorded. Since the tracking system in unaiaxial and could not accommodate the azimuth changes, the pointing error was also recorded periodically. The study showed that the elevation error was restrained because of the positive tracking cycles of the system and was in perfect synchronization with the on-off signals of the control system. The peak power obtained from the tracking solar panel was 103 to 120 W against that of 80 109 W in the non-tracking panel at a solar intensity of 75-90 mW/cm².

Keywords: Solar tracking, P-V panel, Pointing error