Making the acoustic case for hysteresis control in switched reluctance machines

Even though plenty has been reported on the excellent advantages of SRM, its main challenge - the unpleasant acoustic behavior - is still fairly unresolved. Most SRM research not only has to cope with machine inherent noise but also with comparatively strong switching harmonics. The aim of this paper is not to completely solve the acoustic problem but to eliminate distinct switching harmonics by implementing an FPGA-based current hysteresis controller. The vibroacoustic results (simulation & measurement) emphasize the acoustic advantage of the broadband hysteresis controller over modulation-based concepts. Hence, this contribution shall be understood as an attempt to revoke the unjustified negative acoustic reputation which sticks to hysteresis control in SRM.