Enhancing grid resilience is proposed through the integration of distributed energy resources (DERs) with microgrids. Due to the diverse nature of DERs, there is a need to explore the optimal combined operation of these energy sources within the framework of microgrids. As such, this paper presents the design, implementation and validation of a Model Predictive Control (MPC)-based secondary control scheme to tackle two challenges: optimal islanded operation, and optimal re-synchronization of a microgrid. The MPC optimization algorithm dynamically adjusts input signals, termed manipulated variables, for each DER within the microgrid, including a gas turbine, an aggregate photovoltaic (PV) unit, and an electrical battery energy storage (BESS) unit. To attain optimal islanded operation, the secondary-level controller based on Model Predictive Control (MPC) was configured to uphold microgrid functionality promptly following the islanding event. Subsequently, it assumed the task of power balancing within the microgrid and ensuring the reliability of the overall system. For optimal re-synchronization, the MPC-based controller was set to adjust the manipulated variables to synchronize voltage and angle with the point of common coupling of the system. All stages within the microgrid operation were optimally achieved through one MPC-driven control system, where the controller can effectively guide the system to different goals by updating the MPC’s target reference. More importantly, the results show that the MPC-based control scheme is capable of controlling different DERs simultaneously, mitigating potentially harmful transient rotor torques from the re-synchronization as well as maintaining the microgrid within system performance requirements.
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Coordination of Protection and Ride-through Settings for Islanded Facility Microgrids
Proliferation of power electronics and distributed energy resources (DERs) into the electrical power system (EPS) enables improvements to the network’s resilience against sudden-inception short circuit electrical faults through redundant electrical pathways in meshed configurations and multiple possible distributed generation locations. However, successful operation of fault detection, isolation, and recovery in islanded mode is challenging as protection coordination must include not only the distribution equipment, but also the DERs. Assessment of resilience for candidate EPS architectures against short circuit faults must be performed to understand the trade-offs between network resilience and complexity. This paper proposes a design process, which can be used towards assessing microgrid resilience, by coordinating protection and ride-through settings to maximize the recoverability of a meshed islanded AC microgrid. The design process is demonstrated through a case-study.
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- Award ID(s):
- 1939124
- PAR ID:
- 10316399
- Date Published:
- Journal Name:
- 2021 IEEE Energy Conversion Congress and Exposition (ECCE)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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