使用先进的控制方法提高GaN-based PFC的功率密度

High switching frequencies are among the biggest enablers for small size. To that end, gallium nitride (GaN) switches provide an effective way to achieve these high frequencies given their low parasitic output capacitance (C OSS ) and rapid turn-on and turn-off times. It is possible, however, to amplify the high-power densities enabled by GaN switches through the use of advanced control techniques.

In this article, I will examine an advanced control method used inside a 5-kW power factor corrector (PFC) for a server. The design uses high-performance GaN FETs to operate the power supplies at the highest practical frequency. The power supply also uses a novel control technology that extracts more performance out of the GaN FETs. The end result is a high-efficiency, small-form-factor design with higher power density.

系统概况

众所周知，图腾柱PFC是高功率、高效率PFC的主力。图1展示了拓扑结构。

基本图腾柱PFC拓扑，其中1和S2是高频GaN开关和3和S4是低频开关硅MOSFETs

图1基本图腾柱PFC拓扑，其中1和S2是高频GaN开关和3和S4是低频开关硅MOSFETs。来源:德州仪器

使用GaN和前述算法的两相5 kW设计示例的照片。

*附件：使用先进的控制方法提高GaN基PFC的功率密度.pdf