The impact of energy efficient equipment on system power quality

Over the last decade, the electrical environment has undergone considerable changes. Society has increased its dependence on efficient electronic equipment and/or systems. This heavy dependence has, in general helped to improve energy efficiency, but at the same time, has introduced power quality problems to various operating systems. This paper discusses the rapid increase in the usage of energy efficient equipment, the most prominent ones of which are electronic ballasts, adjustable speed drives, and electronic power supplies. All this equipment will and can impose detrimental effects on the system power quality. The paper further discusses harmonics introduced by energy efficient equipment in depth, the method of mitigation, and the probable reasonable limits which will be acceptable to both the manufacturers and users. It also covers the "K" factor created to guide specifying power transformers to handle heavy nonlinear loads in the operating systems. Finally it ends with a brief review of the latest IEEE and IEC Standards governing various power quality problems.