A power supply circuit for gate driver of flying capacitor multi-level converters

power electronics;power converter;flying capacitor multilevel converter;multi-level converter;gate driver;power supply;bootstrap;charge pump;isolated dc/dc converter

Ye, Zichao ; Pilawa-Podgurski ; Robert

关键词: power electronics;    power converter;    flying capacitor multilevel converter;    multi-level converter;    gate driver;    power supply;    bootstrap;    charge pump;    isolated dc/dc converter;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/93072/YE-THESIS-2016.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

This work investigates new circuits to provide power for the gate drivers of flying capacitor multi-level (FCML) converters. FCML converters with new GaN power switches have received increased attention due to their potential to achieve high conversion efficiency and high power density. However, one of the major challenges is providing power to its gate drive circuits, as the terminals do not have constant references. The most common existing method utilizes an isolated DC/DC converter, which is bulky and energy inefficient. This thesis introduces three new techniques termed cascaded bootstrap, double charge pump and gate-driven charge pump. A new power supply circuit combining the three techniques altogether is developed and used to deliver the required gate voltage using internally available voltage nodes. The proposed circuit can help shrink the size of the overall converter, and further increase conversion efficiency. Prototypes have been built to show the functionality and simplicity of the circuit. Experimental results show that the proposed circuit is up to 3x more power efficient than the current method, at 1/10 of the cost.