Integration of high frequency current shunts in power electronic circuits

Abstract

The principles that determine the high frequency behavior of current shunts are identified and applied to broaden the concept of shunt construction by viewing the shunt as an integrated part of the power electronic circuit. It is demonstrated that a shunt constructed from discrete components, like a number of resistors in parallel, can have bandwidth performance on a par with shunts constructed from foil. The prerequisite is that the layout and spatial orientation of the elements provide the correct field distributions. Such structures often permit easy integration as a permanent part of the power converter layout. A flat structure constructed in this way demonstrates the principles, which can readily be extended to more complex geometries. Some examples of such complex geometries are given in the form of a high-dissipation load impedance with the shunt as an integral part and a snubber inductance with a shunt integrated into its structure. The necessity for electromagnetic field analysis of the layout or component structure is demonstrated. Examples of integrated shunts are presented with analysis and experimental results. >