Title :
Optimal Trajectory Control of LLC Resonant Converters for Soft Start-Up
Author :
Weiyi Feng ; Lee, Fred C.
Author_Institution :
Center for Power Electron. Syst., Virginia Polytech. Inst. & State Univ., Blacksburg, VA, USA
Abstract :
In this paper, the soft start-up process for the LLC resonant converter is investigated and optimized based on a graphical state-trajectory analysis. By setting a current limitation band, several optimal switching patterns are proposed to settle the initial condition. After that, by sensing the output voltage, the optimal switching frequency is determined within the current limiting band. This virtually guarantees that there will be no current and voltage stress in the resonant tank during the soft start-up process. Meanwhile, the output voltage is built up quickly and smoothly.
Keywords :
optimal control; resonant power convertors; switching convertors; trajectory control; zero current switching; zero voltage switching; LLC resonant converter; current limitation band; graphical state-trajectory analysis; optimal switching frequency; optimal switching pattern; optimal trajectory control; resonant tank; soft start-up process; voltage stress; Capacitors; Limiting; Steady-state; Stress; Switches; Time-domain analysis; Trajectory; LLC resonant converter; optimal trajectory control; soft start-up;
Journal_Title :
Power Electronics, IEEE Transactions on
DOI :
10.1109/TPEL.2013.2261094
