High Efficiency, High Power Density 10kW Flying Capacitor Converter Based on 650V GaN for 800V EV Applications
Emad Nazerian, Ruiyang Yu, Qingyun Huang, Mojtaba Heydari, Houshang Salimian Rizi, Alex Q. Huang
Abstract
In this paper, a high-efficiency and high-density 800V, 10 kW three-level flying capacitor multilevel (FCML) converter with 650V GaN devices is analyzed, designed, and tested. Several modern publications in high-density FCML concentrate on using a large number of levels. Despite the benefits of using many more levels, they add to the design complexity and cost of the converter. However, three-level FCML, which has lower complexity of design as well as control and consists of fewer switches is not studied enough for high-efficiency and high-power-density converters. To fill the gap, this paper intends to present a high-efficiency and high-power-density 800V all-GaN FCML. Also, since the inductor of the FCML is one of the bulky and dissipative components in the circuit, an optimized matrix-inductor is presented. The designed converter is tested to 10kw and achieved a peak efficiency of 98.9 % and power density of 271.2 W/in <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> (16.54 kW/L) including the fan and heatsink.