Open AccessConducted Emi Model for Flyback PFC Converter
Author(s) -
M Ashritha,
M. L. Sudheer
Publication year - 2019
Publication title -
international journal of recent technology and engineering
Language(s) - English
Resource type - Journals
ISSN - 2277-3878
DOI - 10.35940/ijrte.c5867.098319
Subject(s) - emi , electromagnetic interference , electronic engineering , electromagnetic compatibility , power factor , flyback transformer , transformer , flyback converter , spice , switched mode power supply , datasheet , engineering , computer science , electrical engineering , voltage
Power Factor Correction (PFC) units are used at the front end of Switched Mode Power Supply (SMPS) to improve the input power factor. However, they generate Electromagnetic Interference (EMI) which needs to be mitigated to compliant levels prescribed by International Standards. The Electromagnetic Compatibility (EMC) standards have set regulations which require expensive instruments and environment for their measurement. Hence there is a need for predicting Conducted EMI by simulation before the product is tested for full compliance to reduce the complexity of the circuit design and cost. To estimate the Conducted EMI, it is important to identify the main noise sources and their conduction paths. This can be achieved by simulating the circuit using the exact models of the transformer, capacitor, PCB trace, and the switching semiconductors. In this paper these components of PFC flyback converter are modelled using SPICE models, datasheet defined component parameters and experimental measurements. The theoretical analysis and simulation results show that the method discussed can predict and analyse the Conducted EMI. This is tested experimentally on a Flyback PFC converter working in Critical Conduction Mode. A line filter is designed and used to bring the noise to compliant levels. Simulation and Experimental results after using the line filter are also presented.