Power quality indexes for continue and discrete disturbances in a distribution area

Abstract

Power quality has become an increasing concern to utilities and customers. The increased concern has resulted in measuring power quality variations and characteristic disturbances for different distribution companies. The power quality disturbances can be categorized by two areas: continues and discrete disturbances. Power quality monitoring of many different sites in a typical distribution network area produces an enormous amount of data. Thus, the power quality assessment and identification of problems and prioritization process between different sites are very difficult. Individual and global power quality indicators for all disturbances and a set of measurement instruments are introduced to power quality analyses in this paper. This paper explains the results of power quality indexes for 50 customer loads at two voltage levels 20 kV and 400 v. The measurement period for continues disturbances is 7 days with 10 minutes intervals. Also this survey has been presented according to IEC61000 and Iranian Power Quality Standard (IPQS). IPQS has some differences from IEC61000, EN50160 and IEEE in power quality indexes, which are investigated in this paper.