Owing to the significant number of hybrid generation systems (HGSs) containing various energy sources

coordination between these sources plays a vital role in preserving frequency stability. In this paper

an adaptive coordination control strategy for renewable energy sources (RESs)

an aqua electrolyzer (AE) for hydrogen production

and a fuel cell (FC)-based energy storage system (ESS) is proposed to enhance the frequency stability of an HGS. In the proposed system

the excess energy from RESs is used to power electrolysis via an AE for hydrogen energy storage in FCs. The proposed method is based on a proportional-integral (PI) controller

which is optimally designed using a grey wolf optimization (GWO) algorithm to estimate the surplus energy from RESs (i.e.

a proportion of total power generation of RESs: Kn). The studied HGS contains various types of generation systems including a diesel generator

wind turbines

photovoltaic (PV) systems

AE with FCs

and ESSs (e.g.

battery and flywheel). The proposed method varies Kn with varying frequency deviation values to obtain the best benefits from RESs

while damping the frequency fluctuations. The proposed method is validated by considering different loading conditions and comparing with other existing studies that consider Kn as a constant value. The simulation results demonstrate that the proposed method

which changes Kn value and subsequently stores the power extracted from the RESs in hydrogen energy storage according to frequency deviation changes

performs better than those that use constant Kn. The statistical analysis for frequency deviation of HGS with the proposed method has the best values and achieves large improvements for minimum

maximum

difference between maximum and minimum

mean

and standard deviation compared to the existing method.