Photovoltaic (PV) systems play a vital role in mitigating renewable energy issues ranging from the oil crisis to environmental concerns. The given paper proposes a grid-connected PV power system with high voltage gain (VG) and a high-speed multiphase buck-boost converter. With this converter, PV panels can be integrated in any fashion as per varying climatic conditions without affecting the switching stress. Also, the proposed system makes use of maximum power point tracking (MPPT) concept with fuzzy logic control (FLC) algorithm in order to reduce losses and complexities associated with the system. For validation of the system, an annual dataset related to global solar irradiance across three locations in Tamil Nadu is taken into consideration. The proposed system is validated and compared with traditional MPPT methods based on power output (W) and energy efficiency (%). It includes the computation of predicted mean (PM) values and comparing them with actual mean (AM) values of solar radiation for each of the locations. The results show a good correlation between the predicted and actual values and higher efficiency, thereby making the proposed system suitable for forecasting solar irradiance. © 2025 Elsevier B.V., All rights reserved.