Planar Transformer For High Power Density

The fast development of electrical power supply, DC-DC converter raise excelsiorrequirement to the power supply: low profile, high power density and highperformance. The proposal of the subject of the high power density planar transformerstudy is just adapted the development. The research of the dissertation puts emphasison reducing the planar transformer's profile and the transmission loss; enjoy theformulation of theory analysis together with manufacture of actual devices.Firstly, analyzing the structural property, finding the way to reduce the planartransformer's profile, designing a new winding structure and exploring its insulationprocess and assembling process, making some planar transformers and testing them.Test data prove that they can work in high frequency.Secondly, based on the Maxwell's Equations, The one-dimensional foil conductor'scurrent density distribution equals the sum of the independent skin effect and theproximity effect current density distributions, and the one-dimensional foilconductor's loss equals the sum of the independent skin effect and the proximity effectlosses. The effect of the primary and secondary winding widths on the power loss andenergy storage are analyzed for the PCB winding pattern by using Ansoft's 2D FiniteElement Method (FEM), It is demonstrated that when the primary and secondary havethe same winding width, the transformer has the lowest ac-resistance and leakage, thissuggests ways the designer can modify the winding arrangement to minimize the lossof transformer.Thirdly, this paper also gives an example to illustrate how to establish the thermalmodel based on experiments and this method can guarantee the planar transformer'stemperature rise to meet the requirement and shorten the design circle. At last, thedesign process of the planar transformer thermal design method is presented.