Grid-connected PV systems energy extraction improvement by means of an Electric Array Reconfiguration (EAR) strategy: Operating principle and experimental results

This paper applies a dynamical electrical array reconfiguration (EAR) strategy on the PV modules of a grid-connected PV system based on a plant oriented (PO) configuration, in order to improve its energy production when the operating conditions of the solar panels are different, such as in the case of partial shadowing or module failure. The EAR strategy is carried out by inserting a controllable switching matrix between the PV generator and the central inverter, which allows the electrical reconnection of the available PV modules depending on their incident irradiance estimated values. As a result, the PV system exhibits a self-capacity for real-time adaptation to the PV generator external operating conditions in order to improve the energy extraction of the system. The paper details both the operating principle and a set of experimental results carried out on a 1.65 kWp EAR-based grid-connected system.