Conception d'une alimentation à résonance utilisée dans les éclairages à haut rendement énergétique

Abstract

LED lighting has many advantages over other lighting sources, but it requires a power converter to transform the AC voltage source available from the grid in a regulated direct current source. Switch mode power supplies are as of today the best solution to transform power for LED lighting applications. The low cost and the high efficiency of SMPS justify their usage in lighting applications. Many power converter topologies can transform the grid voltage to a constant current source. A resonant power converter especially designed for lighting requirements is built. A second power converter based on a hard switchedPWMtopology is also built for comparison purposes. The resonant switch mode power supply is based on a two stage platform. The first stage is a Boost PFC CrM which builds a high voltage DC link. The critical conduction mode of the input inductor allows for the correction of the power factor and low harmonic distortion of the input current. The second stage is a half-bridge LLC resonant power converter. This stage regulates the output current by controlling the switching frequency of the circuit. The resonant inductors are integrated into the power transformer for higher power density and lower cost. The second power converter, a one stage topology, is the SEPIC PFC CrM. Both inductors are coupled on the same magnetic core allowing for high frequency current steering from the input inductor to the second one. The size of the EMI filter can thus be reduce. The SEPIC PFC CrM operates in critical conduction mode to correct the power factor while regulating the output current with only one controlled switch. Results obtained with both converters are compared. The comparison is based on the operating range and efficiency.

Date	6 May 2014
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Handy Fortin Blanchette (Supervisor)