Reliability studies of a PV-WG hybrid system in presence of multi-micro storage systems

In the last years, distributed generation (DG) and microgrid (MG) technologies have been used to moderate the stress due to main stream utility grid electricity demand increase. The dispatch of renewable distributed energy sources at present is performed in such a way that, when implemented at very large scale, their intermittency can impact on the grids, what leads to concerns in terms of power quality and of reliability of supply. In this paper the attention is focused on MG reliability. On this subject the authors have proposed, in previous papers, opportune configuration schemes of MG constituted by a photovoltaic plant, a Wind plant and an Uninterruptible Power Supply. The goal of this paper is to evaluate the reliability improvements of load supply against network congestions adopting the proposed hybrid configurations in presence of storage systems for each energy source proposing an opportune operating strategy for the energy control system. In particular, the reliability estimation is performed in terms of the number of the critical loads interruptions and in particular of the charge state of storage systems, over a certain period of time by using the Monte Carlo simulation method.