Abstract:

This article introduces a new approach for the grid-connected single-stage three-phase photovoltaic (PV) inverter in distribution network. This approach aims at improving the voltage profile at point of common coupling (PCC) between the PV power system and the grid. This improvement is achieved by regulating the dc-link voltage based maximum power point tracking (MPPT). The MPPT is fully utilized for updating the dc-link voltage reference (DLVR) according to environmental conditions. The updated DLVR is compared to the actual dc-link voltage through adaptive reference integral-proportional (ARPI) controller to develop reference direct current axis and to generate inverter pulses under normal and abnormal conditions. To verify the validity of the proposed approach, simulation results for multiple scenarios such as various environmental conditions alone, various environmental conditions with simultaneous three-phase faults and various environmental conditions with simultaneous voltage dips on 250-kW single-stage grid-connected PV system show the effectiveness of the ARPI controller compared with the grey wolf-based PI controller.<

Keywords: