Modeling and simulation of high frequency micro-transformer using COMSOL multiphysics software for power electronics applications

Abstract

This thesis presents the optimization study of parasitic components in micro-transformer based on the analysis of simulation results. Micro-fabricated transformer operates in high range of frequency is one of the main component in electronic applications related to DCDC converter. The approaches in this project are to design and simulate the winding structure with different configurations, and then analyzing the result of parasitic components by using COMSOL Multiphysics software through Finite Element Method (FEM) in order to obtain the lowest possible result of leakage and mutual inductance. Modeling of micro-transformer, mainly covers most part of miniaturization of the magnetic component through the use of micro fabrication techniques, which consists the materials such as copper for winding structure and silicon oxide for substrate. The proposed method is to model a 1:1 ratio of micro-transformer that can be operated at the range of frequency between 100MHz to 1GHz. Simulation in two-dimensional (2-D) is implemented in order to determine the result of current density and parasitic components in various windings designs while the simulation in three-dimensional (3-D) is utilized to obtain the result of windings voltage and the flow of magnetic flux. Different number of turns with similar thickness to turn ratio shows the independent relationship between mutual and leakage inductance. Track width ratio of copper coils shows the significant changes for result of mutual inductance. As a conclusion, central composite design (CCD) shows that the factor of -2,2,2,-2 has the lowest and optimum result of leakage and winding resistance while track width ratio of 1.2 has the lowest result of inductance at 1 GHz with percentage errors of parasitic components between 2.804% and 16.526%.