Recent progress of the rulemaking on grid-connected photovoltaic generation

The rationale for the connection of distributed generators to the grid in case of abnormal events has been recently changed, passing from the obligation to switch the local generation off to the requirement of keeping it on within a certain range of frequency and voltage variations with respect to the rated values. This paper summarizes the concepts according to which the new requirements have been set up, with particular reference to the photovoltaic (PV) systems connected to Medium Voltage and Low Voltage systems, and overviews the recent upgrades of the Italian rulemaking process. A real case example showing the voltage and current waveforms during the disconnection of the PV generation within a power plant is presented.