基于LLC谐振的LED驱动电源设计

LLC Resonant-based LED Driver Power Supply Design

针对大功率LED路灯照明应用,使用谐振拓扑结构解决驱动电源的效率问题。驱动电路前级采用临界电流模式(BCM)下的升压(Boost)拓扑实现AC/DC变换和PFC功能,后级采用LLC半桥拓扑构建DC/DC恒流源。两级结构能充分利用Boost和LLC的高效率特性,从而使整体效率较高。介绍了电路工作原理和基本结构,详细讨论了主要磁芯元件的设计方法。在此基础上制作了样机,实验结果表明,采用谐振拓扑的两级结构降低了开关损耗,可以高效率的驱动LED路灯。

For high-power LED street lighting applications,resonant topology is used to solve the problem of power ef-ficiency.The pre-driver circuit using BCM Boost topology achieves AC/DC conversion and PFC function,while the post-stage LLC half-bridge topology builds constant current source by DC/DC conversion.The two-stage converter com-bines Boost and LLC converter,getting higher performance by making full use of their intrinsic properties.The basic structure and the principle of the circuit are detailed,especially the design method of the main components.On the basis of the above analysis,a prototype is produced,and experimental results show that resonant topology reduces switching losses,the cicuit can efficiently drive the LED lights.