An Improved Sunflower-Inspired Solar Tracking Strategy for Maximizing Photovoltaic Panel Power Generation

Abstract

A previous study proposed a nature-inspired tracking strategy that mimics the solar tracking behavior of sunflowers driven by the light stimulus and the circadian clock. The approach delivered a good tracking performance with an average tracking error of 0.727° under clear, partly cloudy, and cloudy conditions. However, it incurred high tracking errors caused by false detection brought about by the abrupt changes in the amount of solar radiation during realignment. In addition, the scheme also maintained high stepper motor current consumption due to the use of a fixed stepping resolution. To address these issues, the previous tracking routine was modified to direct the search for the sun’s position to a range of calculated altitude angles where a fine-tuning process will be performed using current measurements and the adoption of a variable stepping resolution during panel reorientation. Experiments were conducted to measure the performance of the modifications in terms of tracking error, power generation, and stepper motor current consumption. A comparison of the performances between the previous and the modified approaches was done to assess the impact of the proposed improvement. The result of the comparison showed that the modifications significantly improved the overall tracking performance of the strategy.