Research On The Optimal Operation Of Regional Integrated Energy System Considering Multi-energy Complement In Market Environment

In recent years,traditional coal-fired power is gradually transforming into more types of clean energy power generation,accelerating the diversification of power generation such as gas,hydropower,nuclear power,photovoltaic and wind power.Therefore,the traditional energy supply system must be transformed,and integrated energy system capable of meeting multiple energy complementary operations has emerged.At the same time,with the gradual advancement of the power system reform and the support of national policies,the resources of the user side have gradually participated in the market transaction process,which makes the relevant power companies not only compete with each other in the transmission and distribution of electricity,but also comprehensive energy services.The optimization operation of integrated energy systems still faces many problems,such as the relationship between multiple energy sources and the coupling relationship between multiple networks,analysis of uncertainties in the system,management of integrated demand response,and multi-system coordination management,etc.Therefore,this paper proposes solutions to the above problems in terms of market and operation,thus providing a favorable theoretical basis for the development of integrated energy systems.The main research contents and results of this paper are as follows:For the energy transmission and energy conversion of the regional integrated energy system,the electricity-gas network model and the energy hub model are respectively established,and the uncertainties brought by wind power,photovoltaic and integrated demand response in the system operation is analyzed;A complementary evaluation index system for various types of energy generation including wind energy,solar energy,natural gas,and other systems is established,covering reliability,economy,flexibility,environmental protection,sustainability and comfort.A synchronous operation mechanism of combined electricity-gas market based on power pool is constructed.Under this market framework,a bilevel optimization model for electricity market and gas market clearing is established.Then a modified diagonalization-alternating direction multiplier method is proposed to solve the established nested bilevel model,and the market behavior of each market participant and the optimal operation result of the system are obtained.Analysis of the uncertainty of renewable energy generation,integrated demand response and network congestion will have great impact on market clearing results and system optimization results.Considering the misalignment of electricity gas markets in scheduling time,and the integrated energy system represented by the integrated energy service provider to participate in the market,the elelctricity-gas two-stage asynchronous market mechanism is established and a two-stage nested bilevel optimization model is established,solved by a modified alternating direction multiplier method.Compared with the synchronous market,integrated energy service providers in the asynchronous market have higher energy purchase costs.Therefore,the synchronization between the power market and the natural gas market will greatly improve the operational economy,reliability and flexibility of the coupled system.Based on the analysis of the resilience and reliability of the electricity-gas integrated energy system,a three-stage robust optimization model of defense-attack-defense is established to formulate the hardening strategy and operation strategy before and after emergencies.The three-stage model is transformed into a bilevel optimization problem,and the nested Benders decomposition algorithm is used to solve the model.Finally,the energy storage(electricity storage and gas storage)system is analyzed when the integrated energy system encounters emergencies.Considering the cooperation and energy interaction of multiple regional integrated energy systems,according to the theory of coalitional cooperative game,a coalitional cooperation model suitable for coordinated operation of multiple energy hubs is established;MVEE method and KY-1st algorithm are applied to deal with the correlation and uncertainties of wind power.The robust optimization model is established.A distributed coalition formation algorithm is presented to realize the iterative solution of the cooperative game model.From the aspects of integrated demand response,energy hub cooperation and the uncertainties and correlations,the factors affecting the operation and economic benefits of the integrated energy system are quantitatively analyzed.Based on the operation of the integrated energy system and the energy market,this paper focuses on how the various stakeholders in the integrated energy system can make market decisions in different market environments.In case of emergencies and uncertain factors,how to make operational optimization adjustments and how to coordinate between different systems to achieve a win-win situation.Decision makers can coordinate,optimize and manage according to the models and methods proposed in this paper based on the actual composition of the integrated energy system,as well as the demands and types of markets.