Analysis and Suppression of Inductive Interference in an Active Integrated Power Electronics Module

The interference between the power stage and the driving circuit is one of the key issues of power module design, especially for those with high power densities, where couplings become more severe. This paper focuses on suppression techniques for inductive coupling. As a demonstration, a 2 kW single phase power factor correction active integrated power electronic module consisting of full bridge rectifiers, a current sensing resistor, and boost converter, is developed employing CoolMOS FET and SiC diodes. The electromagnetic interference mechanism in the module is analyzed and illustrated. In order to reduce the voltage spike of the power devices, three different design patterns of the power stage layout are presented and compared with regard to the reduction of parasitic self-inductance of the critical loop in the power stage. The approaches to reducing the inductive interference between the high di/dt loop in the power stage and the driving loop are investigated, including the proposed flux cancellation pattern for the layout of the high power di/dt loop, reduction of electromagnetic interference sources, and the insertion of a copper shielding layer between them. Finally, the design guidelines are built and verified by the simulation and experimental results.