LLC大功率LED驱动器中关键参数研究

Research on key parameters of LLC high-power LED driver

对于大功率LED驱动器来说,LLC谐振变换的优势在于能在全负载范围内实现零电压开关(ZVS),效率高,EMI小等。重点介绍了LLC谐振变换器的关键参数及其对于谐振电路的影响,测试了不同K值和Q值情况下对输出效率的影响。制作了一台原理样机,实现了开关管的零电压开关(ZVS)和次级整流管的零电流开关(ZCS),峰值效率达到了93.2%。实验结果验证了理论分析的正确性和设计方法的可行性。

For high-power LED driver converter,the whole load range to achieve zero voltage switching（ZVS）,high efficiency, low EMI and etc, were the advantage of LLC resonant converter. The key parameter of LLC resonant converter and the influence of different key parameters to resonant circuit were introduced in detail. The influence of different K and Q values on output efficiency were tested. A prototype was made,the zero voltage switching（ZVS） of switching MOSFET and zero current switching（ZCS） of the secondary rectifier were achieved, and its peak efficiency was 93.2%. The result of experiment verifies the correctness of the theoretical analysis and the feasibility of the design method.