A method to identify exposed nodes in low voltage distribution grids with High PV penetration

The impact of introducing distributed energy resources at the low voltage side of the distribution grid is currently raising new challenges for utilities. In particular, the high penetration of photovoltaic panels (PVs) in radial grids is increasing the active power losses in the branches and the voltage level at some of the nodes. Principally nodes next to PV array installations. This paper presents a methodology based on design of experiments (DOE) to detect such exposed nodes and branches, together with the identification of the main scenarios that cause such problems, characterized by: season, type of day, solar radiation and outdoor temperature levels. The methodology is simulated on a LV network based on the Cigre benchmark Grid with real utility data. The exposed nodes are classified for each feeder from most to least problematic and showed (as expected) sensitivity to seasonality (summertime), characterized by high solar radiation and outdoor temperatures.