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Energy storage systems are an effective solution to manage the intermittency of renewable energies, balance supply, and demand. Numerous studies recommend adopting a shared energy storage system (ESS) as opposed to multiple single ESSs because of their high prices and inefficiency. Thus, this study examines a shared storage system in a grid-connected microgrid. By modifying the power outputs of the energy resources, this work intends to implement an economic dispatch of a shared ESS in order to satisfy the power balance and lower the overall cost of electricity. In this context, an optimization problem was formulated and developed using a mixed-integer linear programming (MILP) model. Furthermore, a pilot project (the Solar Decathlon Africa Village) in the Green & Smart Building Park (GSBP), Benguerir, Morocco, was employed to evaluate and verify the proposed approach. Some comparable scenarios were therefore run in a MATLAB environment. The collected findings demonstrate the efficacy of the developed algorithm in terms of optimizing energy cost reductions and enhancing the integration of renewable resources into the Moroccan energy mix. [ABSTRACT FROM AUTHOR]

Summary: To arrest the frequency nadir for a frequency event, the rapid release of kinetic energy stored in a doubly fed induction generator (DFIG)–based wind farm during the initial stage of an event is needed; however, a significant output reduction of a DFIG prior to the frequency nadir can cause a late but significant frequency decline. This paper proposes a stable stepwise short‐term frequency‐support scheme of a DFIG‐based wind farm that is capable of improving the frequency nadir while quickly recovering the rotor speed. Upon detecting a frequency event, the power reference in the proposed scheme is increased by adding constant power to the reference prior to an event and maintaining it for a preset period determined in association with the frequency nadir. The reference then linearly decreases with the rotor speed to converge the rotor speed to a preset value. To quickly recover the rotor speed, at the preset rotor speed, the reference decreases with the rotor speed and time until it intersects with the reference for maximum power point–tracking control. Simulation results clearly indicate that the proposed scheme can improve the frequency nadir while promptly recovering the rotor speed under the various wind conditions. [ABSTRACT FROM AUTHOR]

This paper proposes a coordinated control scheme for wind turbine generators (WTGs) and energy storage in microgrids with high wind power penetration. The proposed scheme aimed to reduce the system frequency deviation caused by variations in wind power and loads. To stabilize the frequency, the WTG and energy storage system (ESS) are used for kinetic energy generation and electrical energy storage, respectively. When the WTG contributes excessively to frequency stabilization in the microgrid with a high wind power penetration, the system frequency may fluctuate considerably. Thus, it is necessary to adjust the contribution of a WTG and to share it with other sources. To achieve our objective, we proposed a coordinated control scheme between the WTG and ESS that shares their releasable and absorbable energies. The coordinated control consistently calculated the releasable and absorbable energies of the WTG and ESS and determined weight factors related to the energy ratios. Accordingly, the weight factors improved the ability of providing supporting frequency stabilization of the WTG and ESS by increasing the stored energy utilization. The performance of the scheme was investigated using MATLAB Simulink Electrical. The results show that the proposed coordinated control successfully stabilized the system frequency by calculating the appropriate contributions required from the WTG and ESS. [ABSTRACT FROM AUTHOR]