Electromagnetic Interference Simulations for Wide-Bandgap Power Electronic Modules

A simulation methodology that incorporates cosimulation techniques using ANSYS EM tools is proposed to predict radiated and conducted electromagnetic interference (EMI) from power electronic modules. The radiated EMIs for a coplanar wire bonded and wire bondless power electronic modules are simulated and compared. The instantaneous power-levels conducting through the power devices in the wire bonded power module are significantly higher than those for the wire bondless power electronic module due to parasitic circuit element imbalance. These power-levels occur for a very short duration at the turn-ON and turn-OFF of the devices and can be considered as a potential source of radiated EMI emissions. Through the cosimulation technique, it is shown that the wire bondless power electronic module has a better electromagnetic compatibility (EMC) compliance compared with that of the coplanar wire bonded power electronic module. Conducted EMI measurements and simulations are also performed to predict the conducted EMI and validate the simulation methodology. The proposed cosimulation technique can be implemented during the initial design phase of power modules to reduce significant time to physically test module-level EMC/EMI.