Random pulse width PWM modulation for induction motor

A classical space-vector pulse width with equal duration of application of application of zero-state vectors V/sub 0/ and V/sub 7/ was modified. A factor variable k0 (proportional to the time of application of vector V/sub 7/) was introduced. By random changing k0 from 0% to 100% of the combined application time for zero-state vectors, novel random pulse width modulation is proposed for application in voltage source inverters for adjustable speed AC drives. Harmonic spread factor is introduced for quality evaluation of voltage spectra of inverters with the random PWM. Realization of the modulator using the Texas Instruments´ TMS320F240 DSP controller is described and the results of experiments are presented.