A novel and simple approach to suppress common-mode EMI in power converters

A novel and simple approach to suppress common-mode conducted electromagnetic interference (EMI) has been proposed in this paper. Taking a boost converter as an example, the method has been explained in detail. The major common-mode conducted EMI generated at the high dv/dt nodes in the converter can be cancelled by constructing steady potential nodes in the circuit, which implemented by changing placement of the boost inductor and using the common-anode diode. Theoretical analysis and experimental results verified this method. Also, this method can be used in other converters such as buck, buck-boost, flyback and PFC circuits etc.