Investigations of electric power quality in the distribution power system of Republic of Macedonia

Power quality is a growing concern both in the utility and with consumers. It has many aspects, and it is difficult to evaluate them all at the same time. This paper focuses itself mainly on the voltage distortion measurement as a main aspect of voltage quality. Possibility of voltage sags and flicker measurement is also given. At the University "Sts Cyril and Mertodij", Skopje, Macedonia, a research program for assessing the voltage quality in a power system has been started. A short description of measurement strategy and methodology for the power network at the Power Company of Macedonia (ESM) is presented. They are carried out as a case study. In this paper the measuring system is described and the results of long term harmonic measurement conducted mainly in the medium voltage network of ESM. Measurement sessions lasted 7 days and were carried out at different locations. Some measurement results and discussions are given.