Thermal Considerations for Y Capacitors in Wide Band-Gap Based Inverters

Power converters based on wide-band-gap semiconductors are source of high level of electromagnetic noise and coupled with stray capacitance inject common-mode noise currents into the system. To respect limits given by international norms, this current will close through safety capacitors either used stand-alone or into a CM filter. Joule losses on the equivalent series resistance of these device are becoming important and thus we propose an analysis on heat generated inside these capacitors and how to avoid potential failure due to thermal stress of these components. Experimental characterization has been done on a commercial device to verify power losses and heat transfer capabilities.