Using vehicle-to-grid to maximize the integration of intermittent renewable energy resources in islanded electric grids

This paper presents the results of a dynamic behaviour analysis study developed with the objective of quantifying the amount of wind power that can be safely integrated in an isolated electricity grid where Electric Vehicles (EVs) are present. The assessment was performed considering two distinct situations: a) when EVs are only in charging mode and b) when EVs participate in primary frequency control. The test system, a small island, contains, in addition to wind generation, a small amount of solar PV plants and four conventional diesel generators. Only wind power influence in system's frequency was assessed since, from a dynamic perspective, this is the renewable resource whose high intermittency level might be more harmful for the electric system operation. Sudden wind variations were simulated and, for both situations, a) and b), the amount of Intermittent Renewable Energy Sources was maximized, keeping always the grid frequency within the limits defined by the power quality standards.