Paper Info
Title
Digital quasi-random modulated SFAVM PWM in an AC-drive system
Abstract
A main research topic in PWM-VSI inverter-driven electrical machines is to reduce the generated acoustic noise which often is dominated by a multiple of the switching frequency in the inverter. This paper proposes a modulation scheme for reducing the acoustic noise effect from an AC machine which can be implemented digitally for low and high performance systems. The scheme is based on a stator flux asynchronous vector modulation (SFAVM) imposed by a digital band limited PWM white noise generator for varying the switching frequency randomly. The white noise generator can be used for 8, 16 and 32 bit microcontrollers. The modulation strategy is tested in a 1 kVA high performance 16 bit microprocessor controlled AC drive system. Voltage-spectra on the line-to-line voltage and the acoustic noise spectra are presented and show that the new modulation strategy can decrease the noise effect. The stator-flux-polygon and the line current are measured and demonstrate the random modulation strategy. Finally, the total sound pressure level from the AC machine is investigated with fixed switching frequencies and with different randomly modulated frequency spans. It is concluded that a properly chosen fixed switching frequency has the lowest total sound pressure level. However, the random modulation strategy distributes the noise frequencies and the noise is more comfortable and less annoying.
Year
DOI
Venue
1994
10.1109/41.315270
Industrial Electronics, IEEE Transactions  
Keywords
Field
DocType
AC motors,acoustic noise,digital control,electric drives,invertors,machine control,magnetic flux,microcontrollers,noise abatement,pulse width modulation,stators,switching circuits,white noise,16 bit,32 bit,8 bit,AC motor drives,PWM-VSI,acoustic noise,digital control,inverter,line-to-line voltage,microcontrollers,performance,random modulation,sound pressure level,stator flux asynchronous vector modulation,stator-flux-polygon,switching frequency,voltage-spectra,white noise generator
Noise,Noise (electronics),Phase noise,Noise figure,Control engineering,Electronic engineering,Noise spectral density,Engineering,Noise generator,Noise (radio),Electrical engineering,White noise machine
Journal
Volume
Issue
ISSN
41
5
0278-0046
Citations 
PageRank 
References 
2
2.79
0
Authors
2
Name
Order
Citations
PageRank
J. K. Pedersen143.35
Frede Blaabjerg21195248.32