Optimal allocation and energy management of a wind-hydrogen generation system equipped with the speed regulating differential mechanism

The hybrid drive wind turbine (WT) can be friendly connected to the power grid by using a speed regulating differential mechanism (SRDM) instead of partially- or fully-rated converters, which has been considered as a promising solution for the stable consumption of large-scale wind power generation. To further improve the on-grid performance of hybrid drive WTs, this paper develops a multi-source power generation scheme, in which a hydrogen storage system (HSS) is integrated for mitigating the wind power generation intermittencies. The overall architecture and kinematic principles of the proposed wind-hydrogen generation system, called SRDM-based WT with HSS, are firstly analyzed. Then, the graphical descriptions of mathematical models are finalized via the Energetic Macroscopic Representation (EMR) method, by which the physical characteristics and energy flow relationships are revealed. To ensure the economical and stable operation of the proposed wind-hydrogen scheme, an effective optimal allocation framework, considering the uncertainties from wind power output and load demand, is presented to HSS, targeting the maximum annual revenue. The effects of several key HSS parameters on the capacity allocation results are also investigated. Moreover, aiming at the different system working modes, an energy management approach is synthesized to achieve the interaction analysis and power supervision between energy sources and storage elements. Finally, experimental and simulation case studies are demonstrated. Results illustrate the effectiveness of the proposed approaches and the optimal performance for uninterrupted on-grid operation of the proposed wind-hydrogen energy system.