Can Frequency Be Used to Achieve Communication-Less Primary Control in Photovoltaic-Storage Islanded Microgrids?

In the new energy scenario Renewable Energy Sources are playing a central role especially if energy islands are concerned. In particular, energy islands without synchronous generation, for example photovoltaic storage, are of major interest if one aims at a sustainable transition of these systems. In this Microgrid structure Grid-Forming and Grid-Feeding inverters need to be properly managed in order to cope with the features usually provided by the main power grid, i.e. frequency and voltage regulation. This paper wants to provide an analytical demonstration that even in no-inertia islands, the system frequency is still a suitable signal to provide frequency regulation and thus to guarantee the power balance and primary frequency regulation without any need of additional communication among generating units.