High-Efficiency Nonisolated Boost Converter Using LC Resonance for Quasi Soft Switching Operation in PV Applications

This article presents a high-efficiency nonisolated boost converter leveraging LC resonance for quasi soft switching operation. Conventional nonisolated dc/dc boost converters often suffer from efficiency degradation due to high switching operation during turn-on and turn-off events. These losses necessitate bulky heat sinks, increasing the system’s size and cost. To address these limitations, alternative solutions such as interleaved boost converters and coupled inductor designs with soft switching techniques have been proposed. However, these approaches often require multiple active and passive components, resulting in increased system complexity and reduced power density. The proposed converter employs a single SiC mosfet to achieve cost reduction and design simplicity in a 10 kW power system, operating at a switching frequency of 100 kHz. By integrating an LC resonance design, the switching occurs at a specific point in the resonance waveform, enabling quasi soft switching and significantly reducing switching losses. Simulations and experimental results validate the proposed converter’s performance, demonstrating a high efficiency of 99.0% at 10 kW output, compared to the conventional boost converters. Furthermore, the converter’s integration into a dual-active-bridge and back-to-back system confirms its superior power density and efficiency compared to conventional methods.