A prototype of a solar-tracking power-generating system

摘要

This article describes a practical, low-cost closed-loop sun-tracking solar-panel power generator prototype which rotates on a single axis along the east-west direction of the sun's path. It uses photosensors to detect the incident angle of the sun's ray to the surface of the solar panel. The photosensor module consists of three phototransistors, which automatically adapts its sensitivity to the sun's brightness to enhance its function under all weather conditions. The system is controlled by a field programmable gate array (FPGA). The FPGA controls the movement of the motor in short 50ms pulses every 3 s during tracking mode followed by 3 min of sleep mode. This method produces small angular step movement of the solar panel with little expense of battery power. At night, a photoresistor detector will enable the controller to switch off most parts of the system to further reduce power consumption.