Comparative investigation of PWM current-source inverters for future machine drives using high-frequency wide-bandgap power switches

Abstract

Pulse-width-modulated (PWM) current-source inverters (CSIs) in machine drives have received limited research attention since the 1980s because they are generally considered to be inferior to PWM voltage-source inverters (VSIs) in terms of several performance metrics. However, in view of the special features of wide-bandgap (WBG) power semiconductors that distinguish them from today's silicon devices, this paper uses simulation to reexamine the PWM-CSI's key performance metrics including efficiency, electromagnetic interference (EMI), and machine over-voltage at high switching frequencies (e.g., 200kHz) compared with two-level WBG-enabled VSIs under similar operating conditions. Advantages of the CSI compared to the baseline VSI topology are revealed for each of these three performance features. Reverse-voltage-blocking switches based on gallium nitride (GaN) High Electron Mobility Transistors (HEMTs) that are key to the operation of PWM-CSIs are discussed and experimentally evaluated.