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This paper presents the developments and the results of an analytic method elaborated to design isolated intercell transformers. These particular magnetic components are intended for multicell interleaved flyback converters recently proposed and well-suited to low-voltage, high-power applications. A specific 2-D model to evaluate the winding losses is included in the design process. The results, obtained for standard core shapes, allow defining the ranges of the main parameters, number of cells, and switching frequency, required for future realizations. [ABSTRACT FROM AUTHOR]

An original converter composed of interleaved flyback is presented. The cells are interconnected through intercell transformers replacing the standard multi-winding inductors used as insulation and storage magnetic device in the flyback. The combination of the interleaving effects and of the intercell transformer characteristics allows eliminating the mains limitations of the standard flyback due to the low performances of multiwindings inductors. In a first part, the different ways to interleave galvanic insulated converters as forward or flyback are briefly recalled. The second part presents the intercell transformers and shows that they can be used to interconnect interleaved converters cells. In the third and last part, this particular magnetic interconnection is applied to inter- leaved flyback cells and leads to create an "intercell transformer fly-back". Its specific properties and advantages are described. Experimental results, obtained on a 2-kW test bench are finally presented. [ABSTRACT FROM AUTHOR]

The induction heating principle has been successfully introduced for about 20 years in domestic cooking appliances. The technical developments now concern the improvement of the current appliances and the introduction of new functions. So, one tendency is the design of multiwinding induction coils that are very adaptive concerning the shape and the power capability. This paper describes different original converter topologies designed to supply multiwinding coils, and, in addition, multicoil systems. The proposed topologies are based on particular use and associations of zero-voltage switching series-resonant converters. They are all characterized by a frequency-synchronized operating mode, in order to prevent any acoustic harm that could result from beating frequency-interferences. [ABSTRACT FROM AUTHOR]

Power-factor-corrector (PFC) converters are now commonly used in low-power supply systems connected to ac net- works. In addition to their basic PFC properties, they constitute the best technical solution to directly obtain the compatibility with a large range of ac voltages provided by different distribution networks around the world (typically, from 85 to 265 V rms). It is the main application of these converters. This function is achieved with an additional cost and volume, and this extra price to pay needs to be minimized. In this context, we first recall the main approaches of the de- sign of conventional PFCs based on the boostconverter topology. We emphasize the different critical points of the sizing that mainly concern the input choke and the silicon devices, in regard with the choice of the switching frequency. Few ways of improvement are then presented for these conventional PFCs. In a second part, always in the context of a large input voltage range, we consider the possibility to introduce the multi-level concept to reduce the input choke and filters. A solution using a multi-level flying Capacitor Two-Cell converter is presented. It is shown that it can lead to a significant increase of the performances, with several options of sizing which can be suited to different requirements of the applications. [ABSTRACT FROM AUTHOR]