Research On The Distributed Energy System Planning And Operation And Benefit Evaluation Based On Active Distribution Network

In the situation of adjustment and change in global energy sector,accelerating energy revolution as well as accelerating construction of clean,low-carbon,safe and efficient modern energy system has become the inevitable choice for China's energy development and transformation in new situation.The idea of "building energy Internet with power generation-grid-load-storage coordinated development and complementary integration" is proposed in the" 13th Five-Year Plan".Energy Internet,as the future direction of the world's energy development,is an important means to promote the energy revolution.From the point of view of the construction of the energy Internet,the distributed energy system(DES)is the necessary network "node".Distributed energy system is an energy development mode with multiple advantages such as energy-saving,emission-reducing,safety and flexibility,which is an important way to achieve the energy-saving and emission-reducing target,but also an important direction for the development of power industry.As a new energy supply mode of energy-saving and emission-reducing,it will become an important means to adjust the energy structure of our country.At present,the development of distributed energy system in China is still in its infancy.Under the background of rapid global energy transformation and power system reform,it is necessary to speed up the popularization and application of distributed energy system to realize the efficient and clean development of energy system.The traditional passive distribution network has been unable to meet the environmental requirements and power supply reliability and power quality requirements.Active Distribution Network(ADN)can realize combined control of a variety of distributed energies(DG,controllable load,energy storage,demand side management,etc.),thus it is able to increase the renewable energy capacity of distribution network,improve the utilization of distribution network assets,delay the upgrading of distribution network investment,and improve the power quality and power supply reliability.Therefore,it is of great theoretical and practical significance to study the distributed energy system planning operation and benefit evaluation model under Active Distribution Network.The existing researches have laid the foundation for the planning and operation of distributed energy system accessing to Active Distribution Network,while the current researches mostly focus on the location and capacity problems of the traditional distribution network accessing to distributed energy or Active Distribution Network planning problems.There are rarely researches considering both demand side controllable resources and the interaction of distributed energy system with large power grid,which means that it lacks of a set of comprehensive evaluation system for distributed energy system investment planning taking care of the whole process and all aspects.Therefore,it is necessary to carry out systematic research on these issues.Based on the actual situation of distributed energy system development both at home and abroad,this paper mostly focuses on the investment planning,optimization operation,benefit evaluation,investment model and guarantee mechanism of distributed energy system under Active Distribution Network,aimed at providing analysis and decision-making basis for the relevant subjects.Firstly,this paper studies the problem of distributed energy system accessing to Active Distribution Network investment planning.According to the multi-objective programming theory and method,the objective functions and the constraint conditions of the distributed energy system accessing to Active Distribution Network are established from the purpose of minimizing the annual investment cost and the excision amount of distributed energy output.Based on COA-EO combination model,this paper makes an empirical study on the investment plan of distributed energy accessing to Active Distribution Network system in a certain area in northern China.It is proved by example that the distributed energy system accessing to Active Distribution Network system has a lower annual investment cost,more renewable energy consumption and lower system environment cost than that of not accessing to the Active Distribution Network system,which means that the distributed energy planning combining the Active Distribution Network system has obvious advantages.Secondly,it puts forward the economically optimal operation model of distributed energy system compatible with demand side resources.On the basis of the demand side response model theory,the distributed energy system economically optimal operation model compatible with demand side controllable resources is constructed respectively from the three aspects of power generation cost,environmental cost and reserve cost with full consideration of electrical load,heat load and cooling load in the distributed energy system.A Quantum Improved Drosophila Optimization Algorithm(QIFOA)is proposed in order to solve the above multi-objective and nonlinear optimization problems.And the proposed model and the algorithm are applied to the practical problems of a distributed energy system in Northwest China.Through the comparative analysis,it is found that when the distributed energy system participates in the demand side load optimization management,the total cost of the system will be significantly reduced,and the role of cutting the tip of the valley can be effectively played,thereby improving the using efficiency of the distributed energies.Thirdly,a double-level and two-stage scheduling optimization model of distributed energy system under Active Distribution Network is proposed in this paper.The two-stage scheduling optimization model of distributed energy system under Active Distribution Network double-level energy management is constructed based on the theory of double-level and multi-objective programming theory as well as the economic operation model of distributed energy system with demand side resources mentioned in the previous chapter.Meanwhile,the Differential Improvement of the Imperial Competitive Optimization Algorithm(DE-ICA)is proposed.Based on the example analysis of IEEE-33 node system,it is proved that the scheduling optimization can maximize the consumption of distributed energy and can reduce the running cost of the system,as well as can obviously improve the economic efficiency of the system.In the real-time scheduling,through the effective revision of the previous scheduling,it can further enhance the efficient use of distributed energy,making economic benefits of upper overall and lower regional scheduling optimization of the Active Distribution Network be significantly improved.Fourthly,it studies the evaluation of investment planning benefits of distributed energy system accessing to Active Distribution Network.On the basis of clarifying the constructing principles of comprehensive evaluation index system,the comprehensive evaluation index system of investment planning benefit of distributed energy system is respectively established from the aspects of economic efficiency,social benefits and technical benefits.The investment planning benefit comprehensive evaluation model based on 'combination weight and dynamic fuzzy comprehensive evaluation is constructed from three periods of "history","present" and "future".This paper makes an empirical study on three sets of distributed energy systems in the energy Internet industrial park in the southwest of China.The results verify the validity and feasibility of the model and provide scientific decision-making basis on the studying of the follow-up investment planning model and guarantee mechanism.Fifthly,this paper studies China's distributed energy system investment model and its security mechanism.On the basis of summarizing the advanced experience of distributed energy system operation in foreign typical regions or countries,this paper studies the investment mode of distributed energy system in China,which is divided into investment construction stage and operation and maintenance stage,and constructs distributed energy system investment protection mechanism from the five aspects of policy,market,stakeholder,technical equipment and internal operation,with a view to create more favorable conditions for China's distributed energy system development.