A new approach to enhance power quality for medium voltage AC drives

TLDR

The paper proposes a new approach to medium‑voltage variable‑frequency static AC motor drives that improves power quality. The new drive achieves harmonic currents below IEEE 519‑1992 limits, power factor above 94 % at full load, reduced torque pulsations, insulation voltage stress within limits, and efficiency exceeding 96 %.

Abstract

A new approach to medium-voltage variable-frequency static AC motor drives offers improvements in power quality. Harmonic current injection into the power lines is below the most severe requirements of IEEE Standard 519-1992. The power factor of this new type of drive exceeds 94% at full load and is above 90% at 10% load. Motor voltage and current waveforms are improved so that torque pulsations are reduced. Peak voltage stress on motor insulation does not exceed peak input line voltage, and no zero sequence voltage is imposed. Drive efficiency exceeds 96%. This paper describes the new approach and some of the results achieved.