An Investigation of EMI Reduction Technique using the Spread Spectrum for an Automotive Power Converter

EMI 개선을 위해 자동차용 전력변환기에 적용된 주파수 확산 기법 분석

  • Chae, Gyoo-Soo (Division of Information Communication Eng., Baekseok University)
  • Received : 2017.12.13
  • Accepted : 2018.02.20
  • Published : 2018.02.28


In this study, the investigation results of conducted and radiated emission for DC/DC converter circuit applied in electric vehicles are presented. A frequency spreading circuit was used to improve the EMI characteristics of a power converter designed by using MPQ4433 chip. The frequency spreading circuit using a TLV3201 chip was designed and applied to the power converter. A PCB was fabricated based on the EMI minimization procedures and simulated and measured results were presented for the far-field and near-field conducted and radiated emissions using the fabricated circuit. The measurement were done as CISPR 25 standardized test procedures. It is clearly showed that the EMI characteristics were improved 20% in case frequency spreading was applied. The EMI reduction technique using the frequency spreading proposed in this study was first applied to the design of power converter module for automobile. It is expected that the method presented here can be effectively used for EMI improvement in the future.


Supported by : Baekseok University


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