This paper analyzes the configuration, design, and operation of multi-MW grid connected solar photovoltaic (PV) systems with practical test cases provided by a 10-MW field development. In order to improve the capacity factor, the PV system operates at its maximum power point during periods of lower irradiance, and the power output is limited to a rated value at high irradiance. The proposed configuration also incorporates a utility scale battery energy storage system (BESS) connected to the grid through an independent inverter and benefits of the experience gained with a 1-MW 2-MWh BESS large demonstrator. The BESS power smoothing and frequency regulation capabilities are illustrated though combined theoretical and experimental studies. The behavior of the grid connected PV and BESS combined system is studied using a modified IEEE 14 bus test system implemented in PSCAD/EMTDC. This paper also includes a sizing exercise for energy storage in order to provide dispatchable PV power.

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Published in IEEE Transactions on Industry Applications, v. 55, issue 1.

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The document available for download is the authors’ manuscript version that is accepted for publication. The final published version is copyrighted by IEEE and available as: V. Rallabandi, O. M. Akeyo, N. Jewell and D. M. Ionel, “Incorporating Battery Energy Storage Systems into Multi-MW Grid Connected PV Systems,” in IEEE Transactions on Industry Applications, vol. 55, no. 1, pp. 638-647, Jan.-Feb. 2019. doi:10.1109/TIA.2018.2864696

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Funding Information

The support of University of Kentucky, the L. Stanley Pigman endowment, Power and Energy Institute of Kentucky (PEIK), and of the LG&E and KU utility is gratefully acknowledged.