High Voltage Gain Transformer-Less DC–DC Converter for Fuel Cell Electric Vehicles

The low voltage output of renewable energy sources (RES) such as fuel cells (FCs) and photovoltaic (PV) systems necessitates high-gain, high-efficiency DC-DC converters for electric vehicle (EV) applications. This paper proposes a novel unidirectional transformer-less boost converter with enhanced voltage gain, reduced semiconductor stress, and improved efficiency. The proposed topology operates in two distinct modes, controlled by two switches with the same duty cycle, achieving high voltage conversion without employing a transformer, voltage multiplier, coupled inductor, or complex voltage-lifting techniques. A comprehensive analysis of the converter's operation, voltage gain, and efficiency is provided, along with a comparative assessment against state-of-the-art high-gain converters. The proposed design exhibits a lower component count, reduced voltage stress on power devices, and minimized power losses, making it highly suitable for fuel cell electric vehicle (FCEV) applications. Experimental validation is conducted using a 180 W laboratory prototype, demonstrating the converter's superior dynamic performance and high efficiency. The results confirm that the proposed topology offers an optimal balance of simplicity, efficiency, and reliability, making it a strong candidate for next-generation FCEV powertrains.