PCB-planar transformers equivalent circuit model identification using genetic algorithm

Abstract

Planar passive components are interesting solutions for the design of integrated power converters. Models of planar magnetic devices are still not available in simulator tools. There is, thus, a specific limitation during the design process of integrated power systems. In this paper, an equivalent circuit model for a planar transformer is proposed. This physics-based model includes the magnetising and leakage inductance, the parasitic capacitance and the ohmic loss effects. The skin and proximity effects in primary and secondary windings are modelled by the ladder R-L network. The ladder parameters are identified by minimising the function between experimental and simulation results using the genetic algorithm. The planar transformer simulation results have been tested and favourably compared with practical measurements and 3D finite element method simulation of a large number of transformer designs. A comparative study between experimental data and simulation results is established and found excellent agreement.