Model conducted EMI emission of switching modules for converter system EMI characterization and prediction

Abstract

This paper proposes a new frequency-domain electromagnetic interference (EMI) noise prediction method for switching power converters with variable operating conditions such as DC-AC converters. This work presents a practical and efficient approach that is based on an EMI noise Thevenin equivalent frequency-domain source model (TEFSM) developed at one switching period. The prediction methods for both differential-mode (DM) and common-mode (CM) noise are studied. The methodology is verified by simulations and experiments using a half-bridge converter. This approach can be applied to converters with different switching control schemes. Also it can be applied to a variety of converters, such as DC-DC converters and three-phase pulse-width modulation (PWM) inverters.