Large-signal model of a downstream DC/DC converter for analysis and design of front-end PFC rectifier using computer simulation

For large-signal analysis and design of power supply system with multiple converters, the simulation speed becomes much critical when simulation is employed as virtual prototyping approach. Previously published models for downstream DC/DC converters at the power semiconductor switch level or even the power stage level can hardly meet this requirement. This paper proposes a model that can accurately emulate the input characteristics of downstream DC/DC converters under low frequency small-signal situation or large-signal process. The model is very simple, which makes simulation very fast, therefore can greatly facilitate the design and verification of front-end PFC voltage loop compensator, and the analysis and design of many PFC transient issues in distributed power systems.