Common mode impedance model of power electronic equipment to evaluate noise reduction effect of a line noise filter

Line noise filters are used to suppress the conductive noise on AC-mains. A common mode impedance model of equipment is proposed in order to evaluate the noise reduction effect of line noise filters. First, the article describe how the common mode impedance model is obtained from the equipment equivalent circuit model. Next, in a comparison of the impedance calculated from the model with the measured impedance, it is concluded that the common mode impedance model is useful for prediction of common mode noise suppression.