The Effect of Duty Cycle on Suppressing EMI Level in Random Carrier Frequence Modulation of PWM

Author

Guo, Hai-yan ; Li, Zhao-ji ; Zhang, Bo ; Luo, Ping ; Li, Zhe-hong

Author_Institution

IC Design Center, Univ. of Electron. Sci. & Technol. of China, Mianyang

fYear

2008

fDate

13-15 Dec. 2008

Firstpage

164

Lastpage

167

Abstract

Random carrier-frequency (RCF) modulation has been applied to DC/DC converters, reducing conducted EMI significantly. The selection of the duty cycle is critical in terms of suppressing EMI level in RCF modulation. But limited related literature is available. In this paper, we analysis the effect of duty cycle on suppressing EMI level by deduced the expression of the amplitude of switching voltage power spectra under the RCF mode and describe the change trend of PSD versus f in the case of different duty cycle, providing the theoretical basis of selection of duty cycle for low EMI level.

Keywords

DC-DC power convertors; PWM power convertors; electromagnetic interference; frequency modulation; interference suppression; switching convertors; DC/DC converter; EMI level suppression; PWM; RCF modulation; duty cycle selection; random carrier frequency modulation; switching voltage power spectra; Circuits; DC-DC power converters; Electromagnetic analysis; Electromagnetic interference; Fourier transforms; Frequency conversion; Frequency modulation; Pulse width modulation; Switching converters; Voltage; Boost converter; Duty cycle; Electromagnetic Interference (EMI); Power spectra density (PSD); Random carrier-frequency (RCF);

fLanguage

English

Publisher

ieee

Conference_Titel

Apperceiving Computing and Intelligence Analysis, 2008. ICACIA 2008. International Conference on

Conference_Location

Chengdu

Print_ISBN

978-1-4244-3427-5

Electronic_ISBN

978-1-4244-3426-8

Type

conf

DOI

10.1109/ICACIA.2008.4769996

Filename

4769996