Modeling and simulation of an integrated octagonal planar transformer for RF systems

Abstract

The work presented in this paper concerns the modeling of an integrated transformer in monolithic technology for high frequencies containing coils of planar type and magnetic circuit made of several layers of materials. Circular, square, and polygonal shapes of the planar coils are the important difference regarding transformer topologies. In this work, we have chosen the stacked octagonal form of coils. The transformer will be integrated into a converter of type flyback. We have opted for the Wheeler method and the S-parameters for determining the geometrical and the electrical parameters. The electrical π model presented summarizes perfectly the various parasitic effects generated by stacked layers of different materials constituting the transformer. The electromagnetic simulation, by using COMSOL Multiphysics 4.3 software, illustrates the current density and the distribution of magnetic field lines. We have also used software PSIM 6.0, to validate the equivalent electrical circuit of the transformer in flyback converter.