A Solar PV System for Reliable Supply in Areas with Erratic Grid

This paper presents a grid interfaced solar photovoltaic (PV) system, for dependable supply to the locally connected loads. The system is capable to supply power continuously to the three phase and single phase loads. The grid interconnection is maintained when the normal grid is available. On the grid outage, the system does not lose PV power production, and keeps supplying the loads, by switching to standalone mode and disconnecting from the grid. The reliable supply in absence of grid is ensured by a battery energy storage (BES). The grid connection is smoothly restored after resumption of the normal grid. The system isolates the grid from adverse effects of the local nonlinear loads, and performs reactive power compensation and harmonics currents reduction, along with the elimination of the grid neutral current. The system dynamic response is enhanced due to a fast load current estimation technique, and a PV feed forward term.