Reducing storage capacitance in off-line LED power supplies by using integrated converters

Abstract

In this paper a new technique to reduce the LED current ripple and storage capacitance in high power factor (PF) off-line LED power supplies is investigated. The proposed methodology is based on the use of integrated power converters (IPC) to implement the power supply. Thus, the first stage operates in discontinuous conduction mode (DCM) to provide high PF. The second stage can be operated in either continuous conduction mode (CCM) or DCM. A family of IPCs is proposed to be used as LED lamp power supplies. A generalized analysis is carried out in order to obtain the important design equations and conditions. Finally, an example of an IPC is given, along with some experimental results to demonstrate the effectiveness of the proposed technique.