A decentralized approach for frequency and voltage regulation in islanded PV-Storage microgrids

Abstract

Abstract This paper proposes a novel decentralized and communication-less control strategy for frequency and voltage regulation in Photovoltaic (PV)-Storage islanded Microgrids (MGs). The developed approach aims at achieving a suitable management of the different operational assets of the PV-Storage islanded MGs providing seamless transitions among them and guaranteeing a continuous and effective power supply to the loads. Local inverter controllers are designed exploiting the capabilities of the Model Predictive Control; the resulting control architecture is a composition of local Distributed Generating (DG) unit controller relies only on measurements available on the DG unit site that allows nullifying both frequency and voltage errors providing a suitable repartition of the power request. This way, the proposed approach can combine the advantages of the classic droop and master/slave controllers as it needs neither communication among devices nor a secondary centralized control loop. Moreover, it is able to account for the Storage characteristics imposing a power curtailment of the PV units whenever either the power absorption or the State of Charge limit is reached.