International Journal of Science, Engineering and TechnologyAuthors: Premdas T P, Dr. Rajeesh C R
Abstract: Stationary photovoltaic (PV) installations suffer significant energy losses because the panel surface is rarely perpendicular to the incoming solar beam, a phenomenon governed by cosine losses that intensify during morning and evening hours. This paper presents the design, mathematical modeling and simulation-based performance evaluation of a dual-axis sun tracking PV system developed in MATLAB/Simulink. An astronomical, algorithm-based control strategy computes the reference azimuth and elevation angles from geographic latitude, day-of-year and local solar time, while an error-driven, dead-band controller actuates the tracking motors to keep the incidence angle close to zero throughout the day. The single-diode equivalent-circuit model, together with temperature-corrected electrical parameters, is used to translate the tracked irradiance into instantaneous power. Simulation results for a representative 250 W module show that the dual-axis tracker sustains a broad, flat power plateau compared with the narrow bell-shaped curve of a fixed-tilt panel, yielding an energy gain of approximately 30-40%. Field-comparable data from an identical pair of 1.3 kWp systems corroborate the simulation, showing a 36.47% annual energy improvement with the simulated and measured values differing by less than 5%. An economic assessment indicates that, despite a higher upfront cost, the additional energy revenue offsets the investment within a comparable payback period to fixed systems, while a carbon-mitigation analysis confirms measurable emission-reduction benefits. The study concludes that dual-axis tracking is most advantageous for land-constrained, high-yield and research-oriented deployments, whereas fixed systems remain preferable for small residential installations.
