The development of harmonic content and quality of electricity supply measuring system incorporating scada processing

Abstract

When Thomas Edison invented his carbon filament lamp in 1879, gas shares fell overnight. A committee of inquiry was set up to examine the future possibilities of the new method of lighting, and had reached the conclusion that electric light in the home was fanciful and absurd. Today electric light burns in practically every house in the civilised world, with many great advances in the production and use of electricity and electric power supplied by various utilities.

The objective of the electric utility to deliver pure sinusoidal voltage at fairly constant magnitude throughout their system is complicated by the fact that there are currently loads on the system that produce harmonic voltages, which result in distorted voltages and currents that can adversely impact on the system performance in different ways. Because the numbers of harmonic producing loads have increased over the years, it has become necessary to address their influence, when making any additions or changes to an installation.

Quality of supply measurements have long been used to characterise non-linearity on the power system, and have traditionally been measured with expensive portable analysers. A potentially faster, more integrated, and more flexible solution to measure the harmonics with a Supervisory System is accomplished by this research. Any script which aspired to cover in full detail the whole field of a subject so enormous as techniques to measure the quality of electricity supply on a SCADA system, would hardly be practical in less than a few volumes. The pretensions of this research are both modest and of a more immediate value to the reader.