Digital simulation of an adaptive hysteresis current controlled induction motor drive

The performance of an induction motor fed by a transistorized inverter with a variable hysteresis band current controlled PWM (pulsewidth modulation) technique has been investigated. An expression for the hysteresis band is derived in terms of load parameters, and the induction motor is modeled by the reduced order of an actual three-phase motor model. Simulation results on the drive are presented, and harmonic spectra of the current waveform are compared with those of fixed hysteresis band control. With the PWM technique, the current waveform improves significantly, which is evident from the harmonic spectra of the current waveform