Research On Multi-Time Scale Optimal Scheduling Strategy For New Energy Hydrogen Production System

As the installed capacity of new energy power generation devices such as wind power and photovoltaic power generation increases year by year,the amount of wind and light discarded is also increasing.Hydrogen energy,as a kind of green energy with great development prospects and wide application,has been widely concerned in the field of clean energy utilization.The realization of green hydrogen production by using landscape power generation can effectively improve the absorption rate of new energy,and become an effective way to alleviate the problems such as the difficulty of scenery absorption caused by large-scale replacement of fossil energy by new energy.The rational optimal scheduling of new energy hydrogen production system is one of the key technologies to realize the efficient support of hydrogen energy to new energy power generation system.The new energy hydrogen production system is an important carrier to realize energy transformation and green development in the future.Through the multi-time scale optimization scheduling of the new energy hydrogen production system,the coupling relationship between electric energy and hydrogen energy can be fully utilized to realize energy complementarity,improve the utilization rate of new energy and reduce the impact of uncertainties.At the same time,mining the response capacity of electricity and hydrogen load on the user side can realize load clipping and valley filling,reduce system operation cost and further reduce the influence of uncertainty.In this thesis,the multi-time scale operation scheduling strategy of new energy hydrogen production system is studied,mainly in the following aspects:The structure of new energy hydrogen production system under isolated island and grid-connected scenario is constructed,and the similarities and differences between the two are analyzed.The models of wind generator set,photovoltaic generator set,lithium battery,fuel cell,alkaline electrolyzer and hydrogen storage tank were established.The working characteristics of alkaline electrolyzer were analyzed,and the first-order linear expression of hydrogen production capacity and hydrogen production power was fitted,and the relationship curve between efficiency and power of alkaline electrolyzer was obtained.The principle of load demand response is analyzed,and load and demand response types are divided.A multi-time scale optimization scheduling strategy for new energy hydrogen production system in isolated island scenario was established to solve the operating characteristics and the uncertainty of wind power generation and load power.In the previous stage,the optimal scheduling strategy based on the improved radar map model was adopted,and four optimization indexes including load loss rate,load loss rate,system economic benefit and wind and light abandonment were selected.Through the improved radar map model,the objective function was established to obtain the scheduling results taking into account the comprehensive performance of the four optimization indexes.In intra-day stage,the power tracking rolling optimization scheduling strategy based on model predictive control is adopted.The optimization objective is to minimize the deviation between intra-day scheduling results and day-day scheduling plans for electrolytic cell power,lithium battery power,fuel cell power,power abandonment,hydrogen storage tank SOHC and lithium battery SOC.The utilization rate of new energy can be improved and the operating cost of the system can be reduced through the day rolling optimization scheduling.In order to give full play to the role of user-side flexible load,fully tap the potential of demand response resources,and further smooth the fluctuations of source and load power,a multi-time scale comprehensive electric-hydrogen demand response model was established.The price-based demand response strategy was adopted for day-ahead electrical load,and the substitution-type demand response strategy was adopted for hydrogen load.Intra-day phase electricity and hydrogen load adopt incentive demand response strategy.Considering the operation characteristics and the comprehensive electric-hydrogen demand response model in the grid-connected scenario,the multi-time scale operation scheduling strategy of the new energy hydrogen production system in the grid-connected scenario was established considering the comprehensive demand response of electric-hydrogen.In the day-ahead stage,the optimization goal is to minimize the total operation cost of the system.Under the influence of day-ahead demand response strategy,the peak cutting and valley filling of load can be realized on the user side and the economy of system operation can be improved on the system side.The intra-day rolling optimization method of MPC was adopted.Besides the total operation cost,the power deviation penalty cost and demand response subsidy cost were also taken into account.The operating cost of the intra-day rolling optimization dispatching system was further reduced,and the fluctuations of the source and load power were further stabilized.