Economic Scheduling Of Integrated Energy Systems Containing Electricity,Heat,and Natural Gas Based On Conditional Value-at-Risk

With energy and environment issues becoming increasingly prominent,to improve the utilization efficiency of various types of energies has become a key problem to be solved to establish a clean,low-carbon,safe and efficient modern energy system.The integrated energy system,which will be an important form of the next generation energy system,is composed of the electricity power system,heat supply system,and gas supply system.It realizes the coupling of different energy systems in the transmission,distribution,transfer and consumption parts,and has the characteristics of flexible operation,high efficiency and high utilization of renewable energies.Thus,more and more considerations have been given to it.The uncertainty of renewable energy generations such as wind turbine and photovoltaic,and electricity and heat loads poses challenges to the economic scheduling of the integrated energy system,and make the adjustment of the dispatchable energy supply devices more complete.Thus,the corresp onding risk is increased.To decrease the risk,this paper establishes the model of e conomic scheduling of the integrated energy system containing electricity,heat,and gas based on Conditional Value-at-risk.The following researches are carried out:Firstly,this paper studies on the typical structure of the integrated energy system containing electricity,heat,and gas,and reviews the connection among differnet kinds of energies;the mathematic models of electricity supply devices and heat supply systems are built;and based on the component characteristics and basic network laws,the network models of the electricity subsystem,heat subsystem,and natural gas subsystem are built.Secondly,the variables involved in the calculation of steady state multi-energy flow are analyzed,some special problems in the heat and gas subsystems are deduced;on this basis,the model of multi-energy flow of the integrated energy system is established;the Newton-Raphson method used in the power flow calculation of the electricity power system is extended,and the calculation method of multi-energy flow based on Newton-Raphson method is proposed;the Jacobi matrix used in the iteration is derived,and the calculation procedure is presented;the multi-energy flow calculation method is verified used an integrated energy system containing electricity heat and gas.Thirdly,the scheduling risk faced by the integrated energy system because of the uncertainty of supply side and load side is analyzed,and the necessity of using Conditional Value-at-Risk to analyze the scheduling problem is proposed;the uncertainty models of energy supply devices and loads are built,and the definitions and calculating methods of Conditional Value-at-Risk are introduced;on this basis,the model of economic scheduling of the integrated energy system containing electricity,heat,and gas based on Conditional Value-at-risk is established;the mathematic model is transferred into a bilevel optimization model through analysis,and the solving method and procedure based on the particle swarm optimization algorithm and interior point method are proposed.Finally,a small integrated energy system containing electricity,heat,and natural gas is used as an example.The proposed economic scheduling model is simulated and verified;and the influences of the coefficient changes on the simulation results are analyzed.