This article proposes a two-stage power converter with novel control methods for pulsed load applications. The first stage is an isolated converter that transfers only average power to the second stage, which dramatically reduces the input filter size and components’ current rating. The second stage is a buck converter designed for a fast response during pulsed load transients. A flexible intermediate voltage is implemented to reduce the size of the midpoint energy storage capacitor that is responsible for compensating the instantaneous power difference between the two stages. A novel digital input feed-forward controller is proposed for the second stage to eliminate the poor line regulation issue caused by the flexible intermediate voltage. To verify the effectiveness of the two-stage power supply and the control methods, a full-scale 800 W (average)/4 kW (peak) converter prototype is built and tested. The results prove the feasibility of the proposed topology as well as control methods and demonstrate the advantages over traditional concepts.

中文翻译：

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具有高功率密度和快速响应的基于 GaN 的两级转换器，适用于脉冲负载应用

本文提出了一种用于脉冲负载应用的具有新颖控制方法的两级功率转换器。第一级是一个隔离式转换器，仅将平均功率传输到第二级，这大大减小了输入滤波器的尺寸和组件的额定电流。第二级是一个降压转换器，设计用于在脉冲负载瞬态期间快速响应。实施灵活的中间电压以减小负责补偿两级之间瞬时功率差的中点储能电容器的尺寸。提出了一种用于第二级的新型数字输入前馈控制器，以消除由灵活的中间电压引起的不良线路调节问题。验证两级电源的有效性和控制方法，构建并测试了全尺寸 800 W（平均）/4 kW（峰值）转换器原型。结果证明了所提出的拓扑结构和控制方法的可行性，并展示了优于传统概念的优势。