Advanced highly reliable DC-DC power electronics converters for battery charging systems

Abstract

The thesis focuses on the development and analysis of advanced DC-DC converters, incorporating coupled inductors and interleaved PWM switching schemes to enhance efficiency and compactness. The proposed converters address key challenges in power conversion, including minimizing current ripples, reducing filter inductor size, and improving overall reliability. By leveraging high-frequency operation, these converters achieve smaller passive components and eliminate reverse recovery issues associated with MOSFET body diodes, enabling high-efficiency performance. A family of non-isolated converters was designed with features such as the doubling of effective switching frequency, common ground between input and output terminals, and the elimination of short-circuit risks. Furthermore, a novel single-phase non-isolated buck converter prototype demonstrated low current ripples and enhanced efficiency. Additionally, an isolated DC-DC buck converter was developed for renewable energy applications, incorporating phase-shift interleaving to reduce voltage stress and further optimize inductor size. The experimental results validate the proposed converters, showcasing their potential to significantly improve efficiency, reliability, and size for energy storage and electric vehicle battery charging systems.