P2P Electricity Market Mechanisms Under High Proportion Of Renewable Energy

The power system generally adopts a monopolistic power market model in the early construc-tion of the power system.However,with the development of social economy,the demand for electricity continues to grow rapidly,and the drawbacks of the monopolistic power market model are beginning to appear.In recent years,with the rapid development of distributed energy resources and demand side management technologies,the electricity market is developing in an increasingly open direction,and participants in the market must make rational use of market rules to increase own profits or cut electricity costs.Participants in the electricity market have become more proactive,and they hope to have greater flexibility and freedom in choosing who to trade with and in deciding transaction prices and quantities.Therefore,the electricity market is expected to move towards a more decentralized mechanism,which also promotes the development of the Peer-to-Peer(P2P)mechanism in the electricity market.The P2P market is a decentralized market structure based on the principle of cooperative economy,which promotes the exchange of goods among all peers.The deployment of a P2P transaction mechanism can encourage small and medium distributed energy resources and users with demand response to participate in the market,improve the resilience of the power system,and protect the private information of participantsAt the same time,as the proportion of renewable energy in the power generation of the power system has increased year by year,the random fluctuations and uncertainties in the power system have also increased significantly,seriously threatening the stability,reliability and efficiency of the power system.Two strategies are mainly adopted to solve the uncertainty caused by renewable energy in the electricity market.First,in the day-ahead market,the market operator(MO)inten-sively purchase reserve to deal with unexpected power supply shortages in real-time;second,in the real-time market,the power balance can be achieved through quickly adjusting prices to change supply and demand.However,none of these strategies are well integrated with the P2P market mechanism at present.With the increase in reserve demand,we believe that the reserve should also be settled and cleared fairly through the P2P mechanism,and the joint optimization of energy and reserve can ensure the optimality of the market outcomes;for the real-time market,the negotiation transaction time for real-time transactions is very short.Therefore,it is necessary to reduce the calculation and communication complexity of P2P mechanism so that it can be applied to real-time transactions.In the case of a high proportion of renewable energy penetration in the future,how to design a reasonable and sound P2P electricity spot market mechanism has become an inevitable research problem in the development of future power systems.The main content and contributions of this article are summarized as follows:1.The concept of P2P electricity market and the necessity of developing P2P electricity markets are introduced;The state-of-the-art research works of P2P electricity market are introduced,including the existing P2P market structure,hot research issues and methods,and some in-dustrial projects.2.The economy of day-ahead energy and reserve P2P transaction is analyzed.A simple P2P energy and reserve joint electricity market is designed,including a traditional generator,a re-newable energy generator and a user.Participants realize the simultaneous clearing of energy and reserve through P2P transactions.This simple market structure can help to analyze the relationship between individual behaviors and energy/reserve trading prices and quantities.The existence and uniqueness of market equilibrium are confirmed,the relationship between market equilibrium prices and system parameters is revealed,and a distributed algorithm is designed to quickly converge to the market equilibrium.3.A P2P energy and reserve joint electricity market for practical application is designed.In this market,participants can freely negotiate with each other to determine the transaction prices and quantities of energy and reserve.The "versatile distribution" method is utilized to model the uncertainty of renewable energy generation,and the required reserve is determined based on the chance-constrained optimization method.On this basis,a market negotiation trading mechanism based on the Alternating Direction Method of Multipliers(ADMM)is proposed.In addition,in order to further reduce costs,the correlation and complementarity between renewable power generation uncertainties are used,and a hybrid P2P joint market is designed based on a community of renewable power generators.In this market,all renewable power generators share the uncertainty information to the community manager to calculate the total required reserve.4.A synchronous real-time P2P electricity market is designed.We combine online optimization approach and propose to maximize the social welfare in the long run instead of optimizing the market at each time slot,thereby greatly reducing the complexity of computation and com-munication.Then,an innovative online consensus ADMM algorithm is proposed to enable the real-time P2P electricity market negotiation trading mechanism.Further,the algorithm is improved by:1)using the primal-dual variable alternate update process to improve compu-tational efficiency;2)using the projection-based power update process to ensure the balance of transactions among participants;3)considering the DC power flow model by adding a system operator to help calculate the power flows and voltage angles.Finally,a proof of the sublinear regret upper bound of the online algorithm is given,which implies that the social welfare can be maximized on a long-term scale.5.The proposed synchronous real-time P2P market mechanism is further improved and turned it into an asynchronous market mechanism.The operating efficiency of the synchronous market mechanism will be highly restricted by participants with slow computational effi-ciency and low reliability.Therefore,an asynchronous online consensus ADMM algorithm is proposed to enable the real-time P2P electricity market asynchronous negotiation trading mechanism,where all participants can trade freely without waiting for idle or non-working neighboring participants.The sublinear regret upper bound is also proved for the online al-gorithm,indicating that in the long run,the social welfare can still be maximizedFinally,we summarize the research content of the full text,and look forward to the future research direction.