Comparative study of boost and SEPIC DC-DC converters using hybrid nonlinear robust MPPT-based intelligent techniques for photovoltaic applications

Power electronic converters are fundamental to achieving high efficiency in photovoltaic (PV) systems, since their operation relies on effective Maximum Power Point Tracking (MPPT) algorithms. This paper presents a comparative study of Boost and SEPIC converters using five hybrid backstepping control (BSC)-based MPPT techniques: BSC-ANN, BSC-GA, BSC-PSO, BSC-P&O, and BSC-INC. MATLAB/Simulink simulations under varying weather conditions evaluate settling time, response time, stability, power ripple, Integral of Absolute Error (IAE), and tracking efficiency. Results show that the SEPIC converter consistently outperforms the Boost converter. The BSC-ANN method achieves the best performance, with up to 99.60 % efficiency, a 0.05 ms response time, minimal power ripple, near-zero overshoots (0.12 %), and the lowest IAE. Specifically, BSC-ANN/SEPIC achieved 99.60 % efficiency, a 0.05 ms response time, zero overshoot, and minimal ripple power, while BSC-ANN/BOOST also showed excellent performance with 99.31 % efficiency and a 1 ms response time. In contrast, traditional methods such as BSC-P&O resulted in lower efficiency and longer settling times, confirming the superiority of backstepping-based intelligent MPPT strategies for PV systems.