A Numerical Comparative Study on Losses and Power Capacity in Low Voltage AC/DC Systems: a Philosophy Focused on Distributed Energy Resources

This paper investigates the converting feasibility of low voltage alternating current (LVAC) networks into low voltage direct current (LVDC) counterpart. Addressing the insertion of distributed energy resources (DER) in the grid, in terms of electrical losses and power capacity, the work proposes a methodology supported by computational simulation aiming at the increase of the system efficiency. The study is conducted on a low voltage European residential network model, where the conventional LVAC and an equivalent LVDC topologies are confronted. Based on several scenarios, with and without the presence of DER in different penetration levels and also considering unbalanced loads, the DC configuration demonstrates to be an adequate interface for the insertion of DER, reducing losses and facilitating the integration of new resources. Corroborating with the well-known benefits assigned to the high voltage direct current systems (HVDC), the relevance of the investigation can be highlighted by the advantages observed also in low voltage level.