| Developing renewable energy based hydrogen production system is an effective way to achieve the strategic goal of “carbon peaking and carbon neutralization ”.The complementary hydrogen(H2)production from various renewable energy sources(RESs)can be used to convert the intermittent renewable power generation into green H2 with high calorific value.The long-term storage and rapid power regulation characteristics of H2 can prolong the utilization hours of RES generation and reduce the instability operation of power systems with high-penetrated RESs.In addition,the produced green H2 has high application value in the hydrogen automobile industry of the transportation field.However,the electrolysis power from the wind and solar generation is intermittent and volatile,and the long time electrolysis power fluctuation by a large margin will significantly reduce the service life of electrolyzers and the electricity-to-H2 conversion efficiency.Besides,the energy consumption of electrolysis process is high,resulting in low utilizatio n efficiency of RESs and bringing challenges to the economic operation and market participation for renewable energy based hydrogen production systems.The research is conducted from the aspects of multi-energy coordinated scheduling and market trading mechanisms for multi-renewable-to-H2 production systems,covering the dynamic modeling of H2 production from hybrid RESs,the analysis of electricity-H2 interactions and couplings,and control strategy for suppressing electrolysis power fluctuations.The rolling horizon based two-layer multi-time scale scheduling method for renewable-dominated hydrogen refueling stations(HFSs)and the multilateral multi-energy trading strategy for electricity-H2 integrated hybrid charging stations(HCSs)are investigated.Thereby,the theoretical methodologies of multi-energy coordinated scheduling as well as trading mechanisms in electricity and H2 market for multi-renewable-to-H2 production systems have been formulated.The key contributions of this paper are as follows:1.A multi-renewable-to-hydrogen production method is proposed to enhance the green H2 production efficiency and facilitate various RES accommodation.In this method,the aqueous electrolysis of native biomass can be powered by wind and solar generations based on electrochemical effects,and both electrolysis current and temperature are taken into account for facilitating on-site H2 production and reducing the electricity consumption.The temperature-dependent electrode kinetic model and the resistance-capacitance thermodynamic model for the electrolyzer stack are formulated to analyze the H2 yield under different operating temperatures,currents,and voltages.A life degradation cost model of the electrolyzer considering the influence of electrolysis power fluctuation is developed and incorporated into the multivariable coordinated control strategy to suppress high fluctuations of electrolysis power.The simulation results show that the proposed multi-renewable-to-hydrogen can remarkably reduce the system operation cost,and the average electrolysis efficiency is increased by 14.62% compared with the traditional P2 G method.2.This thesis proposes a hierarchical multi-time scale scheduling method for renewable-dominated HFSs,where the long-time scale rolling optimization of the upper layer and the short-time scale dynamic adjustment of the lower layer are formed based on the model predictive control framework.In the upper layer,a partial differential equation(PDE)model based on fluid dynamic theory is formed to capture the temporal and spatial dynamics of traffic flows for estimating the H2 demands from hydrogen-powered vehicles(HVs)parking at HFSs,and the redundant H2 can be converted back into electricity to opportunistically perf orm the energy arbitrage in the electricity market.The electrolysis power fluctuation is suppressed with the fast-response battery energy storage in the lower layer,and thus the life degradation cost of the electrolyzers is reduced.3.A coordinated multi-energy trading mechanism is proposed for the hybrid-renewable-to-H2 production system(HRPS)to efficiently participate in electricity and H2 markets.In this mechanism,the HRPS can harvest various RESs for green H2 production and procure stacked profits from both the electricity and H2 markets.A Vickrey model-based auction pricing mechanism is formed to determine the H2 trading price and quantity while eliciting truthful offers and bids in a competitive H2 market.A noncooperative single-leader-multiple-follower Stackelberg game with an iterative solution algorithm is formulated to coordinate the interactions between the leading H2 auctioneer and following trading participants for reaching the Stackelberg equilibrium and achieving the win-win goal.The utilities of H2 retailers can be incorporated into the decision-making process of HRPS using the strong duality theory and the Karush-Kuhn-Tucker(KKT)optimality conditions.4.A multilateral multi-energy trading strategy is proposed for synergetic H2 and electricity transactions among electricity-H2 integrated HCSs.In this strategy,the surplus electricity/H2 production of each autonomous HCS with various RES endowment can be accommodated by external multilateral transactions considering the product differentiation to enhance the local renewable utilization while increasing the profits of the HCS cluster.Besides,each HCS is modeled as a sustainable energy hub,and multiple hubs with multi-energy transactions contribute towards a low-carbon energy-transport nexus.Moreover,A distributed multilateral pricing algorithm with incentive compatibility and limited information exchange is developed to decompose the complex multi-energy trading problem into local energy-autonomy subproblems of energy hubs,and the optimal transaction prices and quantities for electricity and H2 can be iteratively derived in a distributed manner.The simulation results show that the proposed strategy can increase the total profit of the HCSs by13.28% and the accommodation rate of wind and solar generation by 12.23%. |
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