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Engineering Commons

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2019

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Electrical and Computer Engineering

Power and Energy Institute of Kentucky Faculty Publications

Energy storage

Articles 1 - 3 of 3

Full-Text Articles in Engineering

Measurement And Estimation Of The Equivalent Circuit Parameters For Multi-Mw Battery Systems, Oluwaseun M. Akeyo, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel Sep 2019

Measurement And Estimation Of The Equivalent Circuit Parameters For Multi-Mw Battery Systems, Oluwaseun M. Akeyo, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

This paper proposes and validates through simulations and measurements, a procedure for the determining the equivalent circuit parameters of large utility-scale batteries. It is considered that a large battery includes multiple cells connected in series and parallel, and therefore, its equivalent circuit can be represented as a series-parallel network of state of charge (SOC) dependent resistors and capacitors. Tests for determining these equivalent circuit parameters are proposed. These tests involve subjecting the battery energy storage system (BESS) to multiple charge and discharge cycles, while monitoring the terminal voltage and current response. A method for post-processing and analyzing the measurements in …


Modeling And Simulation Of A Utility-Scale Battery Energy Storage System, Oluwaseun M. Akeyo, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel Aug 2019

Modeling And Simulation Of A Utility-Scale Battery Energy Storage System, Oluwaseun M. Akeyo, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

This paper presents the modeling and simulation study of a utility-scale MW level Li-ion based battery energy storage system (BESS). A runtime equivalent circuit model, including the terminal voltage variation as a function of the state of charge and current, connected to a bidirectional power conversion system (PCS), was developed based on measurements from an operational utility-scale battery demonstrator. The accelerated response of the battery unit was verified by pulse discharging it from maximum to minimum SOC and its application for grid resiliency was demonstrated through an example droop control frequency response. For the purpose of validating the equivalent BESS …


Incorporating Battery Energy Storage Systems Into Multi-Mw Grid Connected Pv Systems, Vandana Rallabandi, Oluwaseun M. Akeyo, Nicholas Jewell, Dan M. Ionel Jan 2019

Incorporating Battery Energy Storage Systems Into Multi-Mw Grid Connected Pv Systems, Vandana Rallabandi, Oluwaseun M. Akeyo, Nicholas Jewell, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

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 …