Zero Voltage Switching Switched-Tank Modular Converter for Data Center Application

Recently, Switched-tank converter (STC) using zero current switching (ZCS) for 48 V-12 V data center application has reached 98.55% efficiency. However, the C
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loss is not recycled and it increases with frequency and voltage. This paper describes a switched-tank modular (STM) converter with zero voltage switching (ZVS) for all devices over full load range. It can eliminate C
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loss and further improve efficiency. Different from traditional STC, the STM is more modularized and much easier to be integrated into high voltage application. Besides, the STM converter has smaller clamping capacitance compared with large clamping capacitor in traditional STC. As a result, higher efficiency and power density can be achieved. In this paper, the ZVS operation for STM converter is discussed. Also, the efficiency and power loss comparison using GaN and Si devices is analyzed. The simulation and experiment results based on a Si prototype are presented.