A novel current sourced ultrasonic carrier PWM converter with the IGBT in the near future

Abstract

A novel current sourced ultrasonic carrier PWM (pulse-width modulated) converter using an insulated gate bipolar transistor (IGBT) with self-aligned DMOS structure is described. The sinusoidal waveform compared with the ultrasonic corrected triangular waveform method is used as the PWM pulse pattern to operate the converter. Because of the ultrasonic PWM carrier frequency, the converter transforms the AC line current waveform into the sinusoidal waveform, the filter connected to the AC side of the converter can be reduced in size, and the displacement factor is improved. When the PWM carrier frequency f/sub c/ is=20.64 kHz, the displacement factor is improved compared with f/sub c/=4.08 kHz.<>