Economic Dispatch And Renewable Energy Accommodation Of Integrated Energy System

With the world energy crisis,environmental pollution and climate change becoming more and more serious,improving energy efficiency,reducing emissions of pollutants,and mitigating global warming have become important problems that need to be solved urgently in all countries of the world.Integrated energy system(IES)can provide a new way to keep the sustainable development of energy system for its special advantages,such as IES can realize coordinated planning and optimal operation of multiple energy sources,can improve the security and self-healing ability of social energy supply system,can promote the efficient use of energy resources and reduce the operation cost of the whole energy system.However,due to the large number of coupling components and the large scale of IES,and the high nonlinearity of the power flow equation in the electrical network,natural gas network and the heat network,the calculation efficiency and the convergence of the optimal dispatching problem cannot be guaranteed,which bring great challenges to economic dispatch of IES.In addition,as the penetration of wind and solar in the IES increases,demand-side fluctuations also increase,leading to system uncertainties increase sharply,the phenomenon of wind and solar curtailments in the system is serious,which poses a threat to the reliability of the IES.It is urgent to carry out relevant research on the renewable energy accommondation of the IES.Therefore,aiming at the above problems,this paper studies the linear modeling of economic dispatch optimization problem and the analysis of renewable energy accommodation of IES.The main research work is as follows:(1)A linear gas flow model without the need of integer variables is presented,which the SDAE deep learning approach is utilized to predict the gas flow.Then,a special setting of the linear interval is proposed,and theoretical proof is provided.Further,the linearization error is also discussed.Based on the linear gas flow model,a fully-linear economic dispatch model of the electricity-gas system is formulated.Taking IEEE14-NGS14,IEEE39-NGS31 and IEEE14-NGS10 as simulation examples,the Cplex solver is used to solve the linear model.The simulation results show that the economic dispatching optimization model proposed in this paper is far superior to the traditional MILP model in computational efficiency.(2)Based on the power system,natural gas system and heat system,a renewable energy accommodation model consider thermal energy storage and electric boilers are proposed,which includes energy flow model and load curtailments optimization model.Then,an index system is constructed to quantitatively evaluate the improvement effect of thermal energy storage and electric boiler on the wind and solar curtailments as well as the influence on the electric/gas/heat load of the system.A renewable energy accommodation potential analysis method for the IES considering thermal energy storage and electric boiler is proposed.Finally,two simulation systems,IEEE9-NGS6-DHS7 and RTS24-NGS20-DHS14,are analyzed by using IPOPT solver.The simulation results verify the positive effect of thermal energy storage and electric boilers on the improvement of wind and solar curtailment in the system.