The impact of different PV system grid integration approaches on voltage profile, grid losses and behaviour of PV system owners
M. Pintarič and G. Štumberger Faculty of Electrical Engineering and Computer Science, University of Maribor, (Slovenia) 2026-01-20

Abstract

Distribution grids in individual countries inside the European Union have different properties, while the grid operators use different approaches to integrate photovoltaic (PV) systems into the grid, which influences the voltage profile, grid losses and grid’s hosting capability. This work deals with a 0.4 kV distribution gird characteristic for the Slovenian countryside.
The grid users are relatively sparsely distributed in the space. The distances between them are relatively long, while the load distribution among individual phases is unbalanced. Three different approaches to the integration of PV into the grid are discussed. The one used before 2012 with the concentrated larger PV units placed close to the transformer busbars, the one introduced with a net-metering scheme where larger PV units are randomly distributed in the grid, and the one where smaller PV units are evenly distributed throughout the grid. The case study discusses the impacts of the three approaches on the proper voltage profile provision, network losses and behaviour of the PV system owners.

Key words: Low voltage distribution grids, approaches to integration of PV systems, voltage profiles, grid losses,
behaviour of the grid users.

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