Waveform Distortion and Correction Circuit for PWM Inverters with Switching Lag-Times

Abstract

The switching lag-time that prevents the phase shortage of inverter arms causes serious waveform distortions and fundamental voltage drops in pulsewidth-modulated inverter output. Distortions in the PWM inverter-fed induction motor system over the various frequencies of the carrier are investigated and a correction circuit with PWM potential feedback is proposed; the effectiveness of that circuit is shown by experiments.