Power Quality

Abstract

This chapter discusses various power quality phenomena, with particular focus on the implications on power electronic converters and equipment. The end-user's definition of power quality also centers around their ability to use the delivered energy in the desired manner, but the topics considered can be much more specific and include magnitude and duration of different events as well as waveshape concerns. Load current returning in the neutral conductor will, at the point of improper connection to ground, divide between neutral and ground. This current flow in the ground conductor will produce a voltage at the load equipment, which can easily disrupt equipment operation. While switching converters of all types produce harmonics because of the non-linear relationship between the voltage and current across the switching device, harmonics are also produced by a large variety of “conventional” equipment. Most equipment is not sensitive to the voltage fluctuations that cause flicker complaints. The change in output of incandescent lamps as viewed by human observers becomes objectionable at levels of change around 0.3%, but electronic equipment will not be affected at all.