一种半桥LLC谐振变换器数字软启动控制

Digital Soft-starting Control of Half-bridge LLC Resonant Converter

针对LLC谐振变换器在启动时会产生很大谐振浪涌电流的问题,探讨了一种3段式软启动控制策略。分析了谐振电流的启动过程和轨迹,在分析基础上详细介绍了数字软启动控制策略的实现方法,以TMS320F28035为核心搭建了一台480 W 32 V/15 A实验样机。实验结果表明,该数字软启动策略能大幅减小谐振浪涌电流。

Aiming at the huge resonance surge current genertated when starting in LLC resonant converter, a threestep soft-starting control strategy is discussed.The starting proceduee and trajectory of resonance current are analyzed,the implementation method of digital soft-start control strategy is introduced on the basis of analysis,and a 480 W 32 V/15 A prototype is built based on TMS320F28035.The experimental results show that the digital soft-starting strategy can reduce the resonance surge current sharply.