A Distributed Peer-to-Peer Energy Trading Mechanism For Urban Community Microgrid System

As massive integration of Distributed Energy Resources(DERs)and demand-side flexible energy resources,the structure,form,and operation mode of the Urban Community Microgrid System(UCMS)will be fundamentally changed.The role of end-users in the UCMS will transform from traditional consumers into prosumers with energy production and consumption capabilities.The coordination and optimization of energy resources among prosumers can be achieved by introducing the Peer-to-Peer(P2P)energy trading mechanism,promoting the economic benefit,energy selfsufficiency,and renewable energy self-consumption of the UCMS.Therefore,the distributed P2 P energy trading mechanism for the UCMS is studied in this paper from the following three perspectives: trading method,operation strategy,and market power modeling and analysis.The specific works are as follows:1)The basic framework of P2 P energy trading in the UCMS is proposed.Firstly,targeting the highly decentralized and the ownership complexity features of DERs in the UCMS,the basic framework of P2 P energy trading is established based on the continuous double auction mechanism.Then,the market-clearing model of P2 P energy trading and the bidding model of prosumers are established,respectively.The solution methods for market equilibrium price and utility are proposed.Case studies show that the proposed method can effectively promote the supply and demand coordination of energy resources among prosumers,meanwhile improving the overall economic benefits of the UCMS.2)A distributed P2 P energy trading method for diversified prosumers in the microgrid is proposed.Firstly,the autonomous energy management model is established for independent prosumers.On this basis,the energy resource quantitative extraction method is proposed for prosumers to generate energy trading supply and demand.Then,utilizing the price acceptance probability indicator,the pricing strategy of P2 P energy trading is established with the objective of maximized benefit expectation.Finally,the implementation method of distributed P2 P energy trading is proposed.Case studies show that the proposed method can achieve the coordination and complementarity of energy in the UCMS without sacrificing privacy preservation.3)An operation strategy for Energy Balance Service Provider(EBSP)in the microgrid considering the elasticity of market supply and demand is proposed.Firstly,a market equilibrium model for P2 P energy trading involving EBSP is established.On this basis,combined with the elasticity of market supply and demand,the energy management and trading strategy for EBSP is proposed to maximize profit.Then,the improved trust-region method and the particle swarm optimization algorithm are adopted for different types of scenario sets to solve the market equilibrium model and the EBSP trading strategy optimization model,respectively.Case studies show that the proposed method can effectively increase the profit of the EBSP,meanwhile reducing the energy dispatching cost of prosumers,achieving energy self-sufficiency,and the renewable energy self-consumption of the community microgrid.4)A game-theoretic method for market power modeling and restraint of aggregator is proposed.Firstly,the market power formation mechanism of the aggregator is analyzed,and the aggregator’s energy management and trading strategy are established considering the price impact factor.Then,a non-cooperative game model for aggregated P2 P energy trading is established,and the existence of Nash equilibrium is proved.Furthermore,the impacts of market power on market price,trading profit,and the overall benefit of the UCMS are analyzed.A method to restrain the market power of the aggregator is proposed by introducing the tentative offers penalty into the market.Case studies show that if the market power of the aggregator is not effectively restrained,the fair distribution of welfare among prosumers and the overall benefit of the microgrid will be negatively affected.The proposed market power restraint method of the aggregator can effectively inhibit the market elasticity perception ability of the aggregator and further alleviate the impact of the aggregator’s price anticipation behavior on the fairness and economic benefits of the UCMS.