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Full-Text Articles in Power and Energy
The Design And Analysis Of Large Solar Pv Farm Configurations With Dc Connected Battery Systems, Oluwaseun M. Akeyo, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel
The Design And Analysis Of Large Solar Pv Farm Configurations With Dc Connected Battery Systems, Oluwaseun M. Akeyo, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
Typically, solar inverters curtail or “clip” the available power from the PV system when it exceeds the maximum ac capacity. This paper discusses a battery system connected to the dc-link of an inverter to recuperate this PV energy. Contrary to conventional approaches, which employ two dc-dc converters, one each for the battery and solar PV system, the proposed configuration utilizes a single dc-dc converter capable of simultaneously operating as a charge controller and a maximum power point tracking (MPPT) tracking device. In addition to improving the overall system capacity factor, increasing the conversion efficiencies and ensuring MPPT stability, the proposed …
Measurement And Estimation Of The Equivalent Circuit Parameters For Multi-Mw Battery Systems, Oluwaseun M. Akeyo, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel
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
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
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 …
Power Utility Tests For Multi-Mw High Energy Batteries, Oluwaseun M. Akeyo, Huangjie Gong, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel
Power Utility Tests For Multi-Mw High Energy Batteries, Oluwaseun M. Akeyo, Huangjie Gong, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
This paper reviews the procedures, layouts and metrics described in the new test manual issued by the Electric Power Research Institute (EPRI), in order to determine the performance and functionality of a utility scale battery energy storage system (BESS). In this approach, the large battery unit is connected to the dc-link of a bidirectional power conversion system (PCS), which may be interfaced with either the utility grid or a load bank for the purpose of estimating the BESS operation and performance characteristics, some of which includes; available charge/discharge energy at rated power, continuous charge/discharge duration, battery ramp rate, and ac …
Improving The Capacity Factor And Stability Of Multi-Mw Grid Connected Pv Systems With Results From A 1mw/2mwh Battery Demonstrator, Oluwaseun M. Akeyo, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel
Improving The Capacity Factor And Stability Of Multi-Mw Grid Connected Pv Systems With Results From A 1mw/2mwh Battery Demonstrator, Oluwaseun M. Akeyo, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
Conventional PV systems integrated with a battery connect the array and the energy storage unit to a dc-link through individual dc-dc converters for maximum power point tracking (MPPT) and battery charge control. This paper proposes a new system configuration, which connects the PV array and battery unit to the dc-link of the system inverter via a single dc-dc converter capable of simultaneously operating as a charge controller and MPPT device. This dc-dc converter is controlled such that it charges/discharges the battery with the amount of power required to maintain the PV array at its MPPT reference voltage. The proposed system …
Multi-Mw Solar Pv Pumping System With Capacity Modulation And Battery Voltage Support, Oluwaseun M. Akeyo, Vandana Rallabandi, Dan M. Ionel
Multi-Mw Solar Pv Pumping System With Capacity Modulation And Battery Voltage Support, Oluwaseun M. Akeyo, Vandana Rallabandi, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
Solar photovoltaic (PV) renewable energy systems are undergoing major technological developments and large-scale field deployment and electric grid integration. This paper proposes a method of expanding the capacity of an existing irrigation farm with additional pumps powered by solar PV. The system includes PV arrays and battery energy storage connected to a common dc bus, which energizes an array of variable speed inverter driven pumps. Capacity modulation is achieved by energizing an optimal number of pumps required in order to meet a particular load demand with minimum supply energy. A grid connection to the dc bus of the power electronic …