Pulsed current source with active control of the on-time current for LED lamp driver applications

摘要

This paper presents a simplified envelope model to study the dynamics of a phase-controlled resonant converter suitable to drive light emitting diode (LED) lamps. The approximate closed form of the transfer function is obtained from the proposed reduced-order model. The fast dynamics of the resonant converter allows us implementing a pulsed current source with active control of the on-time-current free of instabilities and flicker effect with a type II or integral-single-lead controller. A 120W prototype intended for street lighting applications has been built to validate the study.