| Nowadays,with constraints of resource and environment constantly strengthened in China,development of centralized energy has been difficult to meet the requirements of transmission loss,utilization efficiency,environmental pollution and other requirements,while the distributed energy with advantages of proximity to users,high efficiency and other will become the new subject of transformation of energy structure.With storage and conversion of energy,optimization of configuration,in-place complementary consumption of wind,light,gas and other distributed energy,micro energy grid(MEG)meets the demand of loads,such as electricity,heat,cold and gas,which is an important form of complementary utilization of distributed energy.However,the distributed power supply in MEG has the characteristics of intermittency.volatility and uncertainty.When MEG meets its own load requirements,the internal power supply,energy storage and load demandresponse may have residual adjustment capabilities,it has the potential to be a source of flexibility for the higher grid.While multiple MEGs can be optimized for cluster exogenous response to higher grid scheduling,it can bring multi-dimensional benefits such as improving grid safety,delaying flexible expansion investment and reducing coal consumption and pollutant emissions.In addition,there are distributed power generators,conventional power generators,energy storage and flerxibility load cooperation within the MEG.Participating in higher grid dispatching will also derive renewable energy generators,thermal power sets,energy storage and power grid and other external cooperation bodies,It is necessary to establish a reasonable mechanism for distributing benefits and distribute benefits among internal and external cooperation subjects.Therefore,it is of great theoretical and practical significance to reseach the optimization and benefit distribution model of MEG considering hierarchical collaboration.Based on this,the main contents of this paper are as follows.(1)The basic concept,practice status and general mathematical modeling of MEG have been reseached.Based on reseach of the available literature,the concept and characteristics of the MEG are described.The paper clarifies policy development and project practice of MEG,based on the practical construction of MEG at home and abroad,The practical experience is summarized and the general modeling of unit equipment of MEG is carried out from three aspects,type of structure,energy flow relation and model of units.(2)The optimization model of self-balanced multi-objective dispatching for MEG is constructed.A structure containing biomass energy conversion and electrolytic hydrogen production devices for MEG is designed considering the needs of energy conversion and storage in islanded mode.Then,the multi-objective stochastic scheduling optimization model of MEG is established with objective of minimal operating costs.minimal environmental costs and minimum CVaR.Finally.an improved hybrid differential evolution algorithm based on MOEA/D-DE framework is used to solve the multi-objective scheduling optimization model.The results show that the MEG model can achieve the balance of energy supply and demand in islanded mode,and the operating costs,environmental costs and CVaR are reduced by 78.2%.61.8%.and 77.9%,respectively,while power abandonment reduced from 25.6%to 0.9%.As robust coefficient increases,decision makers are more risk-sensitive and robustness coefficient at range of[0,0.25]minimizes cost fluctuations.The improved hybrid differential evolution algorithm has the best Friedman ranking in the contrast algorithm,which proves that it has better Pareto cutting edge and search performance for solving complex multi-objective problems(3)The two-stage robust optimization model of dispatching for MEGs with response to higher grid is constructed.By calculating the residual supply capacity of distributed power supply and surplus adjustment ability of energy storage and demand response,a total capacity analysis model of the epitaxial response of the micro-energy network is constructed.In addition,the influence of scenery uncertainty on the ability of MEGs derivative response is described,and a two-stage robust scheduling optimization model is constructed.The results show that when MEGs is optimized for the outward derivative response to the grid scheduling,dispatching costs and power abandonment of grid reduced by 6.7%and 9.48%.And when the exogenous response capacity of MEGs is greater,the dispatching cost and abandonment rate are higher.The exogenous response force of MEGs is more flexible and adjustable than that of single MEG,and the effect of reducing the coal consumption of the thermal power units is more obvious.As the expected yield of MHG decreases,the total response force decreases,And when it changes within[0.05,1]range,the MEG with higher costs of energy generation has greater sensitivity of expected yield.(4)The model of benefit allocation for MEG incorporating internal and external co-operation is constructed.By analyzing the functional positioning of the cooperation bodies inside and outside of MEG.the concessional relationship between the subjects is clarified,and the model of the synergistic operation benefit is constructed.In addition,considering the difference between the incremental benefits obtained by the external subject and the risk assumed by the internal subject and the environmental benefits,a synergistic benefit distribution model based on improved entropy right and Shapley method is constructed.The results show that the improved Shapley method can reflect the difference of environmental benefits and risks of different subjects.After benefit distributed,the grid and renewable energy generators are respectively given a profit of 0.015 RMB/kW·h and 0.035 RMB/kW·h,while thermal power unit and MEG 1-4 profit 0.004 RMB/kW·h,0.16 RMB/kW·h,0.188 RMB/kW·h,0.727 RMB/kW·h and 1.265 RMB/kW·h,respectively.Compared with the underlying Shapley method,the differentiation of improved Shapley method based on risk increased by 4.5%,indicating that decision makers should choose the corresponding method of benefit allocation according to the importance of different factors. |
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