Suppressing Harmonics in Delta Modulation by Synchronization Hysteresis with the Reference Signal

  • Aurasopon, Apinan (Department of Electronic and Telecommunication Engineering Faculty of Engineering, King Mongkut′s University of Technology Thonburi) ;
  • Kumhom, Pinit (Department of Electronic and Telecommunication Engineering Faculty of Engineering, King Mongkut′s University of Technology Thonburi)
  • Published : 2002.07.01

Abstract

The delta modulation used for controlling the speed of an induction motor has high peak of harmonic spectrum at low speed range causing acoustic noises in the induction motor. This paper proposes to suppress the harmonics by synchronizing the reference signal with the hysteresis windows for controlling the distribution of the switching frequency. As a result we can decrease the peak of harmonic spectrum. The simulation results show that the peak spectrum of harmonics can be reduced up to 60%.

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