一种新型两开关无电解电容LED驱动电路OA北大核心

The light-emitting diode(LED)driver usually needs a large electrolytic capacitor to reduce its low-frequency current ripple.Therefore,the short life of the electrolytic capacitor is an important factor restricting the life of LED driver,and eliminating the electrolytic capacitor is a key to the long-life LED driver.Under this background,a two-switch electrolytic capacitor-less LED drive circuit topology based on flyback converter is proposed.The auxiliary power balance circuit and flyback converter are integrated,and a balance between the instantaneous input power and output power is realized through two switches.The electrolytic capacitor is eliminated,the low-frequency ripple of output current is suppressed,and a high power factor is realized.The working principle of this topology is analyzed in detail,and a control strategy for its circuit topology is put forward.Finally,a 30 W prototype was built,and experimental results verified the feasibility of the proposed topology.