Factors Influencing Common Mode EMI Generation in Boost Converters

This paper gives three factors that govern the generation of Common Mode (CM) Electromagnetic Interference (EMI) in Boost Converters. They are the magnitude of the main power conversion (DC) voltage; the imbalance difference ratios of component values in the circuit and the impedance of the parasitic couplings between switching voltages in the converter and a common ground. These factors are explained in terms of the Imbalance Difference Model (IDM). Although concentrating on CM EMI generation in a Boost Converter, the factors are applicable to all power electronic converters and therefore of general importance.