Near Field Coupling's Impact on Radiated EMI and Mitigation Techniques for Power Converters in Automotive Applications

For power converters in automotive applications, near field couplings can lead to radiated electromagnetic interference (EMI). This paper develops a radiated EMI model to characterize near field coupling's impact on the radiated EMI. Influential factors of near field couplings and power converter's parasitic inductances are analyzed. Based on the developed model, noise reduction techniques are proposed, including capacitor layout improvement and CM choke implementation improvement. Experiments verify the developed model and the proposed noise reduction techniques.