An Integrated Hydrogen Electrolyser Plant for Mitigating Curtailment of a HVDC-Connected Offshore Wind Farm

This paper presents the integration of a hydrogen electrolyser plant with an HVDC-connected offshore wind farm system. A 200 MW offshore wind farm plant based on a 2 MW Type IV GE turbine, scaled up using the NREL method, is modeled along with a large-scale electrolyser plant, and a VSC-HVDC transmission system of 200 MV A (+/- 100 kV DC). This system is connected to a 230kV, 50Hz grid. Simulations were carried out using MATLAB/Simulink 2023a on three scenarios: no electrolyser, limited electrolyser capacity, full-scale electrolyser. The results emphasise the role of electrolyser plants in mitigating curtailment of offshore wind energy by absorbing surplus wind power through the DC link to produce green hydrogen. The placement of the electrolyser plant in the DC-link reduces the AC/DC power conversion stage, therefore it cuts costs and improves overall efficiency. The simulated case studies show that the electrolyser plant effectively absorbed surplus wind power, which would otherwise be curtailed. The required rated power of the electrolyser plant is determined by the nominal curtailed power from the offshore windfarm.