Research On Operation Optimization Strategy Of Park-level Integrated Energy System

In the future,Integrated-Energy System will be the mainly display mode in the energy field,which usually takes electricity and natural gas as the leading energy sources as well as the cold(hot)steam and other various energies.It arouses a heated discussion in the energy field for its excellent performance of utilizing energy cleanlier and more efficiently in the process of production,carriage,storage and consumption.Recently,National Energy Administration has issued a series of notices involving Integrated-Energy System,Multi-energy complementary Mode and Gird-connected Micro-grid,indicating that we have preliminarily met the requirements of developing Integrated-Energy System projects with the help of more mature development and apply including renewable energy electricity generation technology,smart-grid technology,energy storage technology,virtual power plant technology,operation-control technology and artificial intelligence technology(for examples,big data,machine learning and cloud computing,etc.).Generalized Integrated-Energy System involves the transmission,conversion,storage and consumption of primary energy and secondary energy,and it needs to be realized by a gradual running-process.Park-level integrated energy system focuses on multi-energy functional collaboration in micro-grid aspect,which is a typical representative of micro-integrated energy system and the key research in current as well as the realizing path of the Integrated Energy System in the future.In this article,we focus on how to optimize the operation of the park-level integrated energy system(integrated energy micro-grid),and the main contents are as follows.Above all,we analyze and summarize the short-term optimal operation,capacity planning and operation strategies to sum up the recent researches on the integrated energy system at home and abroad.Based on the schematic diagram of the integrated energy micro-grid system,we construct a mathematical model including wind turbines,photovoltaic units,external energy networks,micro-gas-turbine systems,fuel cells,various types of energy storage devices and electric-cooling/hot/gas generation equipment.Next,we build a short-term optimal operation model based on the component mathematical model of integrated energy micro-grid system.Under the condition of equipment operation constraints and timely load balance constraints,this model takes the objectives of minimizing the total operating costs and maximizing the using of renewable.We draw support from the YALMIP tool box to compile the program and apply the CPLEX solver in MATLAB to solve the model,and its validity is verified through multi-scene cases analysis.Last but not the least,we build a micro-grid capacity allocation optimal model based on the model of integrated energy micro-grid optimal operation to design the optimal capacity of the micro-gas-turbine engine,fuel cell and electric-cooling/hot/gas generation equipment under the consideration of annual operating cost of the system.On the basis of mentioned above,we put forward some strategies and suggestions about the actual development and practical operations of the projects for the purpose of providing reference for the implementation.At the end of this article,we summarize all we have researched and propose the future promising development in this area.