The Cascaded Resonant Converter A Hybrid Switched-Capacitor Topology with High Power Density and Efficiency-Slides

Abstract: This seminar will cover the topic of hybrid and resonant switched-capacitor (SC) power converters. This class of converters has received increased attention lately, owing to superior power density and efficiency compared to conventional approaches. Starting with an overview and analysis of conventional SC power converters, the concept of the fast and slow switching limits will be introduced, and the limitations and design constraints of SC converters will be highlighted. Second, the soft charging technique in SC converters through current source behavior and resonant operation will be examined, along with analytical techniques for modeling and comparing the performance of different SC topologies. Then, an example cascaded resonant converter with 99% peak efficiency and 2500 W/in3 power density for data center applications will be analyzed in detail. The key control techniques to achieve such high performance, including zero voltage switching and interleaving control will be presented. Finally, practical challenges such as gate driving and capacitor voltage balancing will be discussed, along with a number of proposed techniques to mitigate such difficulties.