Assessing cloud transient impacts on grid with solar and battery energy systems

To assess the impact of intermittency of rapidly increasing solar photovoltaic (PV) generation on the grid, this paper presents the dynamic modeling and integration of the components that need to be considered including solar PV plant, battery energy storage system (BESS), the grid-tied interface, and the associated control systems. The complexity and accuracy models of these components are suitable for evaluating the cloud transient impact on bulk power system. Of particular interest is the grid inertial response in situations such as for high penetration levels of solar generation and/or the fast cloud transient induced solar generation decrease coupled with outages that recurrently occur in the grid, e.g., a generator trip. The impact of such events on the grid frequency responses is investigated using a simplified simulation approach to account for the irradiance variation patterns. Responsive battery energy storage systems (BESSs) are recognized as an effective means to improve the inertial response, as investigated and demonstrated in this study.