Random pulse width modulation techniques for converter-fed drive systems-a review

Random pulse width modulation (RPWM) techniques for voltage-controlled power electronic converters have been attracting an increasing interest due to the unique effects of these techniques on the converter-supplied drive systems. A number of RPWM strategies have been reported and a beneficial impact on the acoustic noise and vibration has been unanimously agreed upon. The paper presents a synthetic review of the state of the art in the RPWM theory and practice. Topics covered include principles of RPWM, means of randomization, review of the existing RPWM techniques, power spectra, implementation issues, and documented effects of RPWM on electric drive systems