Power quality measurement and diagnosis using multifunctional equipment

The power quality of electrical energy has become a subject of great importance. Nevertheless, there are different approaches to the problems related to power quality, each of which involves the use of a different measurement system: the voltage characteristics must be evaluated using statistical methods, for which long duration measurement is needed; and the study of equipment and problem diagnosis require fast measurement which is very accurate. Waveform analysis is frequently necessary. For all these reasons, statistical treatment is not possible. Moreover, simultaneous measurement of several parameters is needed, as they are interrelated with each other. Consequently, large volumes of information are obtained, which are difficult to deal with and, on occasions, incompatible with each other. The need for two totally different measurement philosophies has led to the development of measuring equipment capable of combining the two systems mentioned. This article describes the application of multifunctional measuring in three real cases: an AC arc furnace, a DC arc furnace, and a wind farm.