Harmonics Reduction in Front End Rectifer of Uninterruptible Power Supplies With Active Current Injection

Abstract

Harmonics are the by-products of modern electronics devices so it is necessary to mitigate the harmonics and offer techniques to mitigation of harmonics. It is greatly hampered by a three phase rectifier used as a front-end ac-to-dc converter in many systems. High power factor is achieved by injecting high-frequency currents into the three-phase rectifier. This study presents the high power factor operation of the converter with reduced total harmonic distortion up to 47.06%. The power quality up gradation is due to highfrequency current injection, at the input of the front-end rectifier. Sinusoidal PWM technique is used for controlling the output voltage. DSP is used for generating the desired gate pulses. The converter has high efficiency, low EMI emissions, high power packing density and suitable for UPS system.

A Simplified Method of Improving the Power Quality in Power Electronic Circuits using a Single Pair of IGBTs

“…Without electricity, the whole world will plunge into darkness, with the country's economy falling drastically -after all, every working device requires electricity. The world, therefore, should grateful to Thomas Alva Edison and Benjamin Franklin, Who discovered this great wonder, a thing of great importance today [21][22][23][24][25][26][27][28][29][30].…”