A novel switched transformer-based microgrid system for energy conservation

The integration of hybrid energy systems plays a crucial role in promoting environmental sustainability. By leveraging renewable energy sources such as solar energy and fuel cells, and reducing reliance on fossil fuels, these systems significantly lower greenhouse gas emissions and minimize environmental impact. This study explores a grid-connected switched transformer designed to enhance power supply efficiency by reducing energy dissipation and generating less heat compared to traditional transformers used in linear power supplies. The research was conducted on a 1 kW photovoltaic (PV) system comprising four 250 W modules, a 100 W fuel cell, and batteries with a 50% state of charge (270 Ah, 72 V) to optimize energy conservation in a microgrid. All units are connected in parallel to a single DC bus via individual DC–DC converters. The proposed energy management strategy prioritizes solar PV and fuel cells as primary energy sources for the load. The system’s performance was evaluated under varying solar irradiation, load conditions, and scenarios with and without batteries. Utilizing the proposed switched transformer control technique (STON/OFFB), power losses were reduced by 50% and 68% compared to conventional control methods (STONNB and STONB).