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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]

With increasing integrations of large-scale systems based on permanent magnet synchronous generator wind turbine generators (PMSG-WTGs), the overall inertial response of a power system will tend to deteriorate as a result of the decoupling of rotor speed and grid frequency through the power converter as well as the scheduled retirement of conventional synchronous generators. Thus, PMSG-WTGs can provide value to an electric grid by contributing to the system's inertial response through the inherent kinetic energy stored in their rotating masses and fast power converter control. In this study, an improved inertial control method based on the maximum power point tracking operation curve is introduced to enhance the overall frequency support capability of PMSG-WTGs in the case of large supply-demand imbalances. Moreover, this method is implemented in the CART2-PMSG integrated model in MATLAB/Simulink to investigate its impact on the wind turbine's structural loads during the inertial response process. Simulation results indicate that the proposed method can effectively reduce the frequency nadir, arrest the rate of change of frequency, and alleviate the secondary frequency dip while imposing no negative impact on the major mechanical components of the wind turbine. [ABSTRACT FROM AUTHOR]