Design and Implementation of Planar Magnetics for High Frequency Applications

Abstract

Over the years many people have been trying to reduce the size and weight of magnetic components and thus the overall system. One attempt at this is to increase the switching frequency of the system. However, this attempt has its limitation due to increased device switching losses. Device limitation usually con rms this frequency to lower value than is desired. An e ective approach, reducing the size and weight is to use the planar magnetic for possible integration with the power circuit and thus eliminating the associated interconnections. Planar magnetics uses the printed circuit board as the winding. This will allow the magnetic component to be implemented into the circuit. The integration of the magnetic component and power circuit will decrease the number of connection, reduce the height, and ensure the parasitic repeatability. Having external connection can cause problem in the system. In this case the system must carry a large amount of current. The connection causes heating from resistance and introduction of inductance due to the connection. This piece of the work deal with the planar transformer for signal isolation and power isolation in IGBT based driver circuit. Here mainly planar core and planar winding is discussed. The factor that play an important role to select planar core and planar winding is also discussed. Simulation of IGBT driver circuit with planar transformer and hardware result of planar transformer and planar inductor are presented.