Three-Phase Resonant Switched Capacitor LED Driver With Low Flicker

This paper proposes a light-emitting diode (LED) driver based on a three-phase resonant switched capacitor (SC) converter. The LED lamp employs chip-on-board (COB) technology, as it is possible to achieve high power density. The three-phase structure provides low ripple current and reduced percent flicker. Besides, it does not use electrolytic capacitors, thus, causing the driver lifetime to increase. The converter active switches are turned off under zero current switching (ZCS) and zero voltage switching (ZVS) conditions, as efficiency is consequently increased. LED dimming is also a prominent advantage, what can be obtained by varying the switching frequency. An experimental prototype rated at 216 W has been developed in order to evaluate the performance of the proposed approach, while results are properly presented and discussed. LED dimming is possible as the output power varies from 50% to 100%. Overall efficiency and power factor are higher than 90% and 0.97 over the entire load range, respectively.