Prediction of the Conducted Electro-magnetic Interference for Average-Current-Controlled Boost Power Factor Correction Converter

With the average current control, the boost power factor correction (PFC) converter will be operated either in continuous conduction mode (CCM) or discontinuous conduction mode (DCM) in a switching cycle under different working conditions, and thus its operation mode includes all-CCM, part-CCM/DCM and all-DCM in a half line cycle. In this chapter, the conducted electromagnetic interference (EMI) spectrum of the boost PFC converter in all the possible operation modes are analyzed, and the input voltage and load conditions for the worst case of the conducted EMI are predicted. Then, the design of the EMI filter is presented. A 300-W prototype of boost PFC converter with average current control is fabricated in the lab, and the worst case of the conducted EMI spectrum and the design of the EMI filter are verified by the experimental results.