Achieving Stability and Optimality: Control Strategy for a Wind Turbine Supplying an Electrolyzer in the Islanded Storage-less Microgrid

TL;DR

This paper proposes a novel control strategy for wind turbines supplying electrolyzers in islanded microgrids without energy storage, focusing on stability, voltage regulation, and maximizing hydrogen output, thereby reducing costs.

Contribution

It introduces a new control approach tailored to the unique power-voltage coupling in storage-less microgrids, enhancing stability and hydrogen production efficiency.

Findings

The control strategy maintains voltage and frequency stability.

It effectively maximizes hydrogen production in case studies.

The approach reduces reliance on costly energy storage systems.

Abstract

Wind power generation supplying electrolyzers in islanded microgrids is an essential technical pathway for green hydrogen production, attracting growing attention in the transition towards net zero carbon emissions. Both academia and industry widely recognize that islanded AC microgrids normally rely on battery energy storage systems (BESSs) for grid-forming functions. However, the high cost of BESS significantly increases the levelized cost of hydrogen (LCOH), compromising economic feasibility. To address this challenge and reduce the LCOH, this paper focuses on a wind turbine (WT) supplying an electrolyzer in a storage-less microgrid and identifies a unique characteristic that challenges the conventional understanding of this microgrid: active power is coupled with microgrid voltage rather than frequency, the latter being entirely decoupled from active power balance. Based on this unique characteristic, this paper develops a new control strategy that maintains power balance, stabilizes the voltage and frequency, and maximizes hydrogen production. The effectiveness of the control strategy is validated through case studies conducted in Matlab/Simulink, especially its capability to maintain stability while maximizing hydrogen production under various conditions.