Introduction of state-of-the-art low-voltage distribution network devices

Abstract

Trends towards the development of distributed generation involve a number of problems related to maintaining the quality of electric energy in medium and, especially, low-voltage networks. The article examines the impact of monitoring the quality of electricity of low voltage classes on the reliability of the electrical network. MSZ EN 50160 and Hungarian Energy and Utilities Regulatory Office (MEKH) standards are considered. In accordance with MSZ EN 50160, the main indicators of the quality of electric energy are considered, such as: frequency, voltage fluctuations, rapid voltage changes, Flicker dose, voltage dips, short-term voltage interruptions, long voltage interruptions, temporary overvoltages of industrial frequency, transient overvoltages between current-carrying conductors and voltage ground , harmonic voltage fluctuations, interharmonic voltage fluctuations. SAIFI and SAIDI are calculated according to the Hungarian Energy and Utilities Regulatory Office. The devices for monitoring the quality of electricity of low-voltage networks are analyzed. The factors affecting the choice of the place of installation of monitoring devices are considered. It is presented how power quality monitoring systems can reduce the number of malfunctions in the 0.4 kV network, and the influence of monitoring systems on the quality of electric power in 6-35 kV networks is considered.