Research On The Optimal Operation Of Electricity-hydrogen Integrated Energy System

In recent years,the pressure of environmental pollution,energy shortage and global climate change continues to increase,and the search for new clean energy sources has become an urgent issue nowadays.As a zero-carbon energy source,hydrogen energy is an important strategic direction to solve the environmental problems and resource problems.At present,the rapid development of renewable energy in China,the rapid and large-scale development of photovoltaic and wind power generation has brought out the problem of power system transmission and new energy consumption,and the long-term storage characteristics of hydrogen energy can solve this problem.As the ultimate energy source of the 21st century,hydrogen energy will become the terminal form of green energy with electric energy in the future,and the integrated electric-hydrogen energy system will be a new energy system.In this paper,we focus on the optimized operation strategy of the electric-hydrogen integrated energy system,which contains various energy sources such as electricity/hydrogen/heat,and the main work is as follows:(1)An optimized operation strategy of the integrated electricity-hydrogen energy system considering multi-day forecast information is proposed.Firstly,a model of the electrichydrogen integrated energy system equipment is established;secondly,when performing the day-ahead optimized operation,the system not only considers the forecast information of the day,but also considers the influence of the forecast information of the future(N-1)days on the optimized operation of the day,uses Monte Carlo simulation to randomize the forecast information of N days,sets different standard deviations according to the far and near degree of the forecast information to cope with the uncertainty of the forecast information,and then K-means clustering is used to cluster the stochastic scenarios into several typical scenarios;finally,an optimal operation model is established,and the optimal scheduling scheme for the day is obtained with the objective function of minimizing the comprehensive operation cost of the system before the day and the correction adjustment cost under different scenarios.The simulation results show that hydrogen energy storage and electric energy storage assume the roles of day-ahead energy transfer and intra-day energy transfer,respectively,and the system economy is significantly improved,wind and light abandonment is reduced,and electric energy storage life is improved.(2)A multi-timescale optimal operation strategy considering long day-ahead time scale and intra-day MPC hierarchical rolling is proposed.First,a refined model of electrolyzer,hydrogen fuel cell and hydrogen storage tank is established,and then an optimal dispatching model based on long day-ahead time scale and intraday model predictive control hierarchical rolling optimization is proposed.In the day-ahead stage,the long time scale optimization considering multi-day forecast information is proposed,i.e.,when performing the day-ahead optimization,the influence of the forecast information of the next two days on the day-ahead optimization is also considered,and the day-ahead energy transfer effect of hydrogen energy can be realized through optimal scheduling,which greatly reduces the abandoned wind and light and improves the overall economic efficiency of the system.In addition,in the intra-day phase,differences in the nature of different energy transfers are considered,and model predictive control is used for hierarchical rolling optimization to track and correct the day-ahead schedule to achieve coordinated operation among multi-energy systems.The simulation results verify the feasibility and effectiveness of the proposed optimal operation strategy.(3)A source-load cooperative optimized operation strategy for an integrated electricityhydrogen energy system considering the participation of hydrogen-fueled vehicles is proposed.At the source side,the power system grid structure is considered,and at the load side,the conventional hydrogen load is considered as the dynamic hydrogen-fueled vehicle load,and its operation principle is analyzed and its mathematical model is established;secondly,the long time scale optimal operation strategy is still considered at the day-ahead stage,and the MPC hierarchical rolling is used within the day to deal with the uncertainty of load prediction information and the difference in the nature of electro-thermal hydrogen energy transmission.The simulation results show that hydrogen energy storage can be reasonably allocated to storage states according to future climate change,and hydrogen-fueled vehicles can choose different hydrogen refueling stations for refueling according to the system optimization strategy.