摘要
针对LED驱动电源功率因数低的问题,依据LED照明电源的特点,选择SEPIC电路作为主电路拓扑实现功率因数校正(PFC)和LED电流控制。传统的SEPIC电路用于功率因数校正时都工作在断续模式下,通过对SEPIC电路的分析,证明了临界连续模式下SEPIC电路也可以实现PFC,并推导出输入输出电压比和功率因数关系的公式,得出当输入输出电压比很小时,功率因数值很高。该电源用单级电路同时实现功率因数校正和LED电流控制,相对两级功率因数校正电路,所用器件少,损耗低,尺寸小,尤其适合空间狭小的照明电源电路。通过实验证明理论分析的正确性。
The brightness of LED can be adjusted by traditional LED driver power, but its power factor is very low. In order to solve this problem, SEPIC topology was used to realize PFC and control of LED current according to character of lighting power supply. Traditional SEPIC converter with PFC function worked in DCM （discontinuous current mode）. It proved that PFC can be realized by SEPIC with boundary conduction mode（BCM）. Through theory analysis and calculation, it was given out that the power factor was high with small value of the ratio of input voltage versus output voltage. Not only controlling the brightness of LED through controlling output current of LED, but also correcting power factor value with single stage circuit which has fewer components and lower power loss can by realized by this circuit. Finally, the theory analysis is proved correct through experiment.
出处
《电机与控制学报》
EI
CSCD
北大核心
2010年第1期41-46,共6页
Electric Machines and Control
基金
西南石油大学科技基金(2007XJZ105)
