GPS-Based System for the Measurement of Synchronized Harmonic Phasors

A measurement system, based on high-performance Global Positioning System (GPS) receivers and general-purpose acquisition (DAQ) boards, for the evaluation of the synchronized harmonic phasors in the nodes of an electric distribution network, is presented. To meet the requirements of different fields of application, two measurement procedures have been implemented: One is based on a fixed observation window, whereas, in the other one, the observation interval is a function of the actual power system frequency. Experimental tests are presented to characterize the measurement system: The results show that the proposed procedures allow the accuracy that is usually required in power quality monitoring of distribution systems to be reached.