无源PFC电路在LED驱动电路中的应用研究

摘要

Aiming at LED driver circuit for low - power filed, due to sile and cost constraints, the driver circuit can not use the active power factor correction(PFC) circuit, leading to the problem of poor factor.It was first analyzed why the factor needs to be corrected.Then, the research was done in passive power factor correction circuit designing and the model of capacity with 20 W LED driver circuit.Based on the research, there were four circuits which were compared with others, so that one valley-fill passive power factor correction circuit was found.Reseach results indicate that it is with low cost and high power factor and the circuit can meet Energy Star standards and there is no crest factor and other issues.%针对小功率LED驱动电路领域中,由于受体积和成本限制而无法使用有源功率因数校正(PFC)电路从而导致电源功率因数较差的问题,首先分析了需要进行功率因数校正的原因,然后对应用于20W LED驱动电路中的无源功率因数电源进行设计,以及电容选型等方面进行研究.对4种不同的无源功率因数校正电路进行了比较,实验结果表明在LED驱动电路中一种填谷式无源功率因数校正电路是低成本、高功率因素的功率因数校正电路,符合能源之星的标准,不存在波峰因数等问题.