Analysis of DC Link Ripple Currents in Three-Phase AC/DC/AC PWM Converters

3상 AC/DC/AC PWM 컨버터의 직류링크 리플전류 해석

  • Park Young-Wook (School of Electrical Engineering and Computer Science, Yeungnam University) ;
  • Lee Dong-Choon (School of Electrical Engineering and Computer Science, Yeungnam University) ;
  • Seok Jul-Ki (School of Electrical Engineering and Computer Science, Yeungnam University)
  • 박영욱 (영남대학교 전자정보공학부) ;
  • 이동춘 (영남대학교 전자정보공학부) ;
  • 석줄기 (영남대학교 전자정보공학부)
  • Published : 2001.07.01

Abstract

In this paper, dc link ripple currents for three-phase ac/dc/ac PWM converters are analyzed in a frequency domain. The expression of the harmonic currents is developed by using switching functions and exponential Fourier series expansion. The dc link ripple currents with regard to power factor and modulation index are investigated. In addition, the effect of the displacement angle between the switching periods of line-side converters and load-side inverters on the do link ripple current is studied. The result of the do link current analysis is helpful in specifying the dc link capacitor size and its life time estimation.

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