Detailed Analysis and Optimization of the Asymmetrical Half-Bridge PWM Converter including Parasitics

Abstract:
The paper presents a detailed analysis of the asymmetrical half-bridge PWM converter. Due to its advantages with regard to efficiency, power density and cost the topology gains increasing attention. Recent publications propose a rough but simple converter model which helps to understand the basic converter functioning. A comparison between measured and simulated waveforms, however, reveals its insufficiency. The simple model fails to predict important converter characteristics. The necessary model refinement considers the actual capacitance and inductance values instead of replacing these components by ideal voltage or current sources. Further, according to previous research, incorporation of parasitic components is inevitable for the development of an optimal design. Thus, the paper identifies the most important parameters and reveals their primary influence on efficiency. Finally, an optimization strategy is proposed.