An innovative EMI reduction design technique in power converters

The present paper deals with the problem of reducing electromagnetic interference (EMI) of switched-mode power converters using gate controlled devices such as IGBTs and power MOSFETs. In order to reduce power losses, these systems rely on fast on/off time pulses, thus producing emissions due to the high-frequency spectral content of pulses. An original design method for switched-mode power supplies is developed allowing to obtain an acceptable compromise between power losses and EMI. Emphasis is placed on the analysis of the commutation cell of the switching static converter in order to demonstrate that it is possible to control the emissions of the device by handling the parameters of the driver circuit. Theoretical analysis is discussed and compared with experimental results of the investigation on the spectrum amplitude of the emissions.