Power Quality Indices of Distribution Feeder in Eastern Croatia under Electricity Market

The reform of the Croatian energy sector began in 2000 in terms of harmonization with the European energy sector. Adoption of the energy acts has created necessary conditions for gradual opening of the national electricity market. HEP DSO - Distribution System Operator which is one of HEP Group companies needs to satisfy the European norm EN 50160. This paper presents the analysis of voltage quality indices for distribution feeder, aggregated and statistically arranged. The research was performed during the Leonardo Power Quality Initiative project, since the Faculty of electrical engineering in Osijek is the LPQI's affiliate partner. Power quality indices were measured according to the EN 50160 norm with the power quality network analyzer QWave Power. Monitoring was performed online continually at a transformer station 110/35 kV. In this paper, voltage events were classified according to the EN 50160 and IEEE 1159-1995, and RMS variation performance indices were calculated