Abstract: Method for detecting an islanding condition of a grid connected energy conversion system and related DC/AC converter apparatus, adapted to optimize performance in terms of preservation of the power quality, provide synchronized perturbation for all the inverters of a plant, provide shut down capability within the time requested by utilities and safety standards and provide immunity to grid frequency fluctuations.

Abstract: A photovoltaic inverter apparatus adapted to be connected at the input to a photovoltaic panel and at the output to a public electric grid and to a user, wherein said inverter apparatus comprises a DC input stage adapted to receive DC electricity generated by said photovoltaic panel; an alternating conversion stage coupled to said input stage, adapted to convert said DC electricity into alternating electricity and to supply it at the output, wherein said alternating conversion stage is configured to transform said alternating electric energy flow in a selective manner; connection means for selectively connecting said alternating conversion stage to the electric grid or to an isolated load in single-phase or two-wire mode, or in three-phase mode.

Abstract: Method for detecting an islanding condition of a grid connected energy conversion system and related DC/AC converter apparatus, adapted to optimize performance in terms of preservation of the power quality, provide synchronized perturbation for all the inverters of a plant, provide shut down capability within the time requested by utilities and safety standards and provide immunity to grid frequency fluctuations.