Title :
ON/OFF Control of a Modular DC–DC Converter Based on Active-Clamp LLC Modules
Author :
Hien Nguyen ; Zane, Regan ; Maksimovic, Dragan
Author_Institution :
Dept. of Electr., Comput., & Energy Eng., Univ. of Colorado, Boulder, CO, USA
Abstract :
This paper studies ON/OFF control of a dc-dc system that contains multiple active-clamp LLC resonant modules operating in parallel. The architecture and the ON/OFF control method yield high overall efficiency and fast transient responses. Two converter models are introduced: 1) a high-frequency model to determine a gate timing sequence that enables fast ON/OFF control, and 2) an averaged model to assist in the system control loop design. The models and the ON/OFF control method are verified by experiments on a prototype consisting of two 1-MHz, 24-3.3-V, 5-W active-clamp LLC modules. The performance of PI and PID system controllers is compared, and capacitor size is analyzed by simulations on systems containing up to 20 modules.
Keywords :
DC-DC power convertors; PI control; on-off control; resonant power convertors; three-term control; transient response; PI system controller performance; PID system controller performance; capacitor size; fast transient responses; frequency 1 MHz; gate timing sequence; high overall efficiency; high-frequency model; modular DC-DC converter; multiple active-clamp LLC resonant modules; on-off control method; power 5 W; system control loop design; voltage 24 V to 3.3 V; Capacitors; Clamps; Integrated circuit modeling; Load modeling; Pulse width modulation; Switches;
Journal_Title :
Power Electronics, IEEE Transactions on
DOI :
10.1109/TPEL.2014.2345793
