Effect of PV array emulator on power quality of PV inverter compared to a real PV array

In Solar Photovoltaic (PV) generation, an increasingly important issue is the reliability of electronics such as inverters, and how efficiently (and reliably) they interact with the local grid. Total Harmonic Distortion (THD) is increasingly important, relating as it does to efficiency and localised heating. PV is intermittent, so to design controlled experiments to evaluate power quality inverter performance, a reliable model of a PV array is needed. This paper describes a Photovoltaic Array Emulator (PVAE), with results compared to a physical array. The system numerical model includes the PV array, a grid connected inverter (and its controller) along with the grid. Some findings are then presented. The power quality of the commercial PV inverter improves with the PVAE compared to an actual photovoltaic array. However, this improvement of power quality does not comply with the IEEE-1547 standard. A bidirectional inverter with battery storage to improve power quality is proposed, which can provide fast active and reactive power to the load with a minimum THD of the output current to 0.64%.