Multi-Time Scale Optimization Of Hydrogen Integrated Energy System

With the target of "double carbon",the transformation and upgrading of the traditional energy system has pointed out the direction,adjusting the energy structure and improving energy utilization has become a top priority.The integrated energy system not only can realize the gradation of energy utilization through the complementation of multiple energy streams,such as cooling,heat,electricity and gas,but also has a role in promoting the sustainable development of energy.Hydrogen energy has the advantages of clean,low-carbon and easy storage.With the maturity of electricity-to-gas technology,building an integrated energy system containing hydrogen based on a high percentage of renewable energy has become one of the important ways to achieve high energy efficiency and deep decarbonization of the system.However,with the introduction of hydrogen energy,more complex system structures and nonnegligible source-load uncertainty make the study of optimal system operation more difficult.In this paper,we construct an efficient hydrogen integrated energy system structure,analyze the influence of hydrogen storage and source-load uncertainty on the optimal operation of the system,and propose a multi-time scale optimal operation method for the hydrogen integrated energy system in island operation mode,and build a simulation system for verification.The main work conducted includes the following aspects:(1)Based on the deep coupling relationship of hydrogen-electricity-thermal multi-energy flow and considering the temperature-efficiency characteristics of electrolyzer,the structure of high-efficiency hydrogen production integrated energy system based on electrolyzer supplemental heat is constructed,and its operation mode and characteristics are introduced,and the mathematical model of variable efficiency electrolyzer and other typical energy equipment is established,which lays the model foundation for the subsequent study of system optimization operation.(2)Based on the above efficient hydrogen production system architecture,considering the source-load uncertainty and the impact of seasonal hydrogen storage on energy flow dispatch,a multi-timescale optimization operation method for hydrogen-integrated energy systems under islanded operation mode is proposed.The method is based on year-round source-load time series data and takes advantage of hydrogen’s ease of long-period,large-scale storage,and uses a seasonal and day-ahead optimization approach to develop output plans for hydrogen storage and other energy devices.And an intra-day rolling optimization with a 15min time scale is used to adjust and reduce the impact of source-load uncertainty on system operational reliability.In addition,for the problem of multiplication of system operation parameters and large scale of optimization solution due to inter-seasonal scheduling of hydrogen storage,an improved kmeans clustering algorithm is used to screen typical days and achieve fast solution.Finally,it is demonstrated through case studies that the system structure constructed in this paper has a large improvement in hydrogen production index,and the multi-timescale optimization operation method helps to mitigate the impact of inter-seasonal hydrogen storage and sourceload uncertainty on the system energy flow scheduling of the integrated energy system containing hydrogen in the island operation mode.(3)Based on the above system structure,the simulation platform of the hydrogencontaining integrated energy system is built.First,based on Thermolib thermodynamic simulation software package,the mechanism model of the system device is improved and perfected,and the device layer controller is designed and built.Secondly,it solves the compatibility problem between the simulation model of hydrogen energy equipment and the simulation model of heat pump,absorption chiller and other equipment,and realizes the energy flow interaction between the simulation models of each equipment.Then rely on Python programming to develop the interface program,by calling the NI VeriStand application programming interface(API)to achieve the operation of the corresponding channel in NI VeriStand,and will send instructions to the simulation model,to achieve the upper computer application management software NI VeriStand and data storage server data interaction.Finally,the above optimization method is used to test the function of the simulation platform and simulate the practical application of the optimization strategy at the same time.