Integrated planar L-C-T component:: Design, characterization and experimental efficiency analysis

In a resonant dc/dc converter, the major part of the volume is filled by passive components. Moreover, all these components have to support all the power flow. On the one hand, this leads to losses in these components and their connections and on the other hand to an important cost of the converter. Concept of integrated passive component, called inductor-capacitor-transformer (L-C-T), is now well known [1], [3], [4], [6], [8] and this paper will present a new prototype which permits to integrate in an unique part an inductor, a capacitor and a transformer. Because it uses only one core with three windings, this component will reduce the volume of the passive part of the converter. By reducing the number of connections it will, also, have a positive effect on losses. After a presentation of L-C-T components, this paper describes a design of this device, using new windings disposition. The proposed structure permits to adjust separately L and C values. Then, to validate the approach, a characterization is carried out, leading to a new model, including dielectric, iron and copper losses.