Research On Planning And Operation Of Comprehensive Energy System With Renewable Energy Resources

Since the 21 st century,with the rapid development of global economy,the deterioration of environmental problems,the scarcity of fossil fuel resources,the uncontrollable growth of energy demand,and the development of multi energy flow system make the current energy supply structure urgently need transformation and upgrading.As an energy supply mode with higher energy supply efficiency and system operation flexibility,integrated energy system(IES)has become the focus of government,industry and universities.IES builds an integrated production and marketing system of electricity,heat,gas and other kinds of energy through the coupling equipment between different energy sources to realize the efficient and flexible supply of energy,and utilizes the coupling relationship of different energy sources as well as the advantages of heat and gas energy storage to improve the balance of supply and demand and the system’s ability to consume renewable energy.Although the advantages of high efficiency,cleanness and flexibility make IES have bright application prospects,the complex coupling relationship of equipment and the uncertainty of renewable energy and load bring many difficulties and challenges to the planning and operation of IES.This paper focuses on three aspects: IES structure and cell modeling,IES planning method considering uncertainty and IES energy coordination and optimal scheduling based on multi time scale.The main work of this paper is as follows:1)The static mathematical model of distributed equipment(gas turbine,gas boiler,refrigeration equipment,p2 g,energy storage equipment,photovoltaic,fan,etc.)in IES is established,and the uncertainty of renewable energy output is simulated.Through the accurate expression of the physical characteristics,economic function and energy conversion relationship of each equipment,the foundation for the study of the planning and operation optimization of IES is laid.2)The method of IES capacity planning considering uncertainty is studied.First of all,considering the uncertainty of renewable energy,in order to make IES economically and reliably meet the demand of each node and each type of load in the whole planning cycle,scenario reduction 0-1 planning model is used to effectively and accurately describe the uncertainty of renewable energy.Secondly,on the basis of the previous research,the uncertain IES capacity planning method is studied,and a mixed integer linear programming model with the sum of investment operation cost as the objective function is established.To solve the problem that the multi scenario planning model can not get the result directly,a two-stage planning strategy is proposed.The effectiveness and feasibility of the proposed method are verified by numerical simulation.3)Based on multi-time scale and multi-source energy storage,energy coordination and optimal scheduling method of comprehensive energy system is proposed.In this method,three time scale optimal scheduling models are established,which are day ahead,day in day rolling and real-time feedback,respectively,aiming at the optimal operation of the system,the minimum sum of the purchase cost and the storage penalty cost in the time domain of rolling control and the minimum adjustment of the output power of the equipment.Considering the influence of various energy storage modes on the economy of IES in the day ahead,and based on the model predictive control method in the day ahead,the feedback closed-loop optimization in the day and in the real time is constructed to suppress the system power fluctuation caused by the prediction error.Through the simulation and comparison of examples,the influence of multi-time scale and multi-source energy storage on the economy and power fluctuation of IES operation is analyzed.