Toward high-efficiency photovoltaic energy harvesting: experimental validation of continuous, hybrid, and sensorless dual-axis tracking systems with fixed-tilt solar system

Abstract

Solar tracking systems have gained considerable attention due to their potential to increase the energy yield of photovoltaic (PV) systems by maintaining the PV module at a favorable orientation relative to the Sun. However, conventional dual-axis trackers often rely on high-power motors and frequent mechanical actuation, resulting in substantial auxiliary energy consumption and depletion of stored battery energy that could otherwise be conserved for nighttime operation. Moreover, variations in solar position caused by daily and seasonal changes, together with unpredictable weather conditions such as cloud cover, make it challenging to maintain an optimum panel orientation while simultaneously minimizing actuator operation. Therefore, developing an accurate and energy-efficient tracking strategy that maximizes PV power generation while reducing unnecessary actuator energy consumption remains an important research challenge. This article emphasizes the design and application of hybrid algorithms: the Sun’s position algorithm and solar angle calculator (SPA-SAC)-based sensorless dual-axis tracker (SDAT). The setup adopts the azimuth angle of the module using SPA and employs SAC to adjust the altitude angle for compensating seasonal variations. Experimental results show that the proposed tracking system achieves a 32.98% average power gain over static systems, 3.28% as compared to continuous tracking systems, and 5.14% as compared to hybrid tracking systems. This innovative approach consumes 72.44% less power as compared to a continuous dual-axis tracker (CDAT) and consumes 19.54% less power than a hybrid tracker (HDAT), which is particularly beneficial for solar trackers with large-sized motors. A 200-W prototype is used for experimental verification. This substantial energy saving is crucial for large-scale solar trackers with high-powered motors. This study indicates potential for developing low-power consumption designs for high-power solar PV systems.