Title :
Spectral characteristics of random carrier frequency switching in off-line switched mode power supply
Author :
Tse, K.K. ; Chung, Henry S H ; Hui, S.Y.R. ; So, H.C.
Author_Institution :
Dept. of Electron. Eng., City Univ. of Hong Kong, Kowloon, China
Abstract :
In this paper, a detailed analysis and the spectral characteristics of a random carrier-frequency (RCF) technique for suppressing conducted EMI in an offline switched-mode power supply are presented. The analysis provides a theoretical platform for studying the characteristics of this random switching scheme. The level of randomness is defined for the RCF scheme and varied in the power converter example so that its effects on the power spectra can be demonstrated. Theoretical predictions of the spectral characteristics of this scheme are confirmed with measurements. Comparisons of the spectral performance show that the RCF scheme has better conducted EMI suppression than the FM and standard PWM schemes
Keywords :
electromagnetic interference; harmonic distortion; power conversion harmonics; switched mode power supplies; switching circuits; SMPS; conducted EMI suppression; offline switched-mode power supply; power converter; random carrier frequency switching; randomness level; spectral characteristics; spectral performance; Communication switching; DC-DC power converters; Electromagnetic compatibility; Electromagnetic interference; Frequency modulation; Pulse width modulation; Pulse width modulation converters; Switched-mode power supply; Switches; Voltage;
Conference_Titel :
Applied Power Electronics Conference and Exposition, 1999. APEC '99. Fourteenth Annual
Conference_Location :
Dallas, TX
Print_ISBN :
0-7803-5160-6
DOI :
10.1109/APEC.1999.749502
