The character and design of LCC resonant converter for constant current applications

Abstract

LCC resonant converter has a good feature of constant current characteristics, which is the ideal driver for medium and high-power LED lighting. In this paper, based on a LCC resonant converter characteristic that the transformer primary side voltage can still be approximated as a square wave when the parallel resonant capacitor capacity is much smaller than the series resonant capacitor, the first harmonic analysis(FHA) is adopted to obtain current gain curve. According to the characteristics of the current gain curve, the optimal operating region selection strategy is proposed, and the calculation method of the LCC resonator and transformer parameters is given in detail. Lastly, a driver with an input voltage of 395 V, an output current of 2 A and an output voltage range of 16 V to 48 V was designed to verify the rationality of the method.

Keywords

• LED drive power
• LCC resonant converter
• constant current output