DM EMI noise prediction in constant on-time PFC

The EMI characteristics of the constant on-time PFC have not been carefully identified because its EMI performance is unclear. In this paper, a mathematical model based on the principle of the quasi-peak detection is proposed to predict the EMI noise of the constant on-time PFC. The developed prediction method is verified by experimental results. The predicted DM EMI noise can match the measured quasi-peak DM EMI noise very well. The proposed mathematical model would be very helpful to the investigation of the EMI characteristics of the constant on-time PFC and the design of the EMI filter.