Title :
Non-isolated topologies for high step-down offline LED driver applications
Author :
Dayal, Rohan ; Parsa, Leila
Author_Institution :
Dept. of Electr., Comput. & Syst. Eng., Rensselaer Polytech. Inst., Troy, NY, USA
Abstract :
In this paper, two non-isolated DC-DC converter topologies suitable for offline Light-emitting Diode (LED) driver applications are presented. The output voltage for such applications is generally less than 42 V DC to satisfy LED lighting system requirements. Isolated converters are normally used for this higher step-down (170V-42V/15V DC) operation. However, an isolation transformer introduces increased complexities in the implementation of feedback and control. Dedicated passive or active circuitry is also required to mitigate the energy in the leakage inductance. The proposed topologies are non-isolated and hence are much simpler in implementation. The converters are suited for two nominal step-down conversions - (1) 170V-42V DC, (2) 170V-15V DC operation while maintaining a reasonable duty cycle and efficiency. Their operation is described in detail. Both the converters can be controlled to achieve active power factor correction. Simulation results with relevant parasitic are presented to verify the claimed step-down conversions.
Keywords :
DC-DC power convertors; driver circuits; light emitting diodes; power factor correction; transformers; DC-DC converter topology; LED lighting system; active circuitry; active power factor correction; isolation transformer; leakage inductance; light-emitting diode; nonisolated topology; offline LED driver; passive circuitry; power factor correction; step-down conversion; Capacitors; Inductors; Light emitting diodes; Lighting; Steady-state; Switches; Topology;
Conference_Titel :
Applied Power Electronics Conference and Exposition (APEC), 2012 Twenty-Seventh Annual IEEE
Conference_Location :
Orlando, FL
Print_ISBN :
978-1-4577-1215-9
Electronic_ISBN :
978-1-4577-1214-2
DOI :
10.1109/APEC.2012.6165939
