This paper proposes a methodology to increase the lifetime of the central battery energy storage system (CBESS) in an islanded building-level DC microgrid (MG) and enhance the voltage quality of the system by employing the supercapacitor (SC) of electric vehicles (EVs) that utilize battery-SC hybrid energy storage systems. To this end, an adaptive filtration-based (FB) current-sharing strategy is proposed in the voltage feedback control loop of the MG that smooths the CBESS current to increase its lifetime by allocating a portion of the high-frequency current variations to the EV charger. The bandwidth of this filter is adjusted using a data-driven algorithm to guarantee that only the EV's SC absorbs the high-frequency current variations, thereby enabling the EV's battery energy storage system (BESS) to follow its standard constant current-constant voltage (CC-CV) charging profile. Therefore, the EV's SC can coordinate with the CBESS without impacting the charging profile of the EV's BESS. Also, a small-signal stability analysis is provided indicating that the proposed approach improves the marginal voltage stability of the DC MG leading to better transient response and higher voltage quality. Finally, the performance of the proposed EV charging is validated using MATLAB/Simulink and hardware-in-the-loop (HIL) testing.
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Optimal Sizing of Battery Energy Storage Systems for Small Modular Reactor based Microgrids
Battery energy storage systems (BESS) are increasingly deployed in microgrids due to their benefits in improving system reliability and reducing operational costs. Meanwhile, advanced small modular reactors (SMRs) offer many advantages, including relatively small physical footprints, reduced capital investment, and the ability to be sited in locations not possible for larger nuclear plants. In this paper, we propose a bi-level operational planning model that enables microgrid planners to determine the optimal BESS size and technology while taking into account the optimal long-term (a yearly simulation with a 15-min resolution) operations of a microgrid with SMRs and wind turbines. Case studies are performed using realistic BESS and grid data for two BESS technologies, i.e., Li-Ion battery
and compressed air energy storage. Numerical results show the
effectiveness of the proposed bi-level model. The pros and cons
of the two BESS technologies are also revealed.
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- Award ID(s):
- 1856084
- NSF-PAR ID:
- 10322843
- Date Published:
- Journal Name:
- 2021 IEEE Kansas Power and Energy Conference (KPEC)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/KPEC51835.2021.9446203
