Research On P2P Trading Strategy Considering Multiple Subjects In Distribution Side

With the deepening reform of the retail side and the increasingly mature of the active distribution network(ADN)technology,it can be predicted that more and more emerging market decision entities,such as load aggregator(LA)and Microgrid operator(MGO),will gradually participate in the power trading in the distribution side market.However,the vertical integration trading mechanism is widely used in most of electricity markets of China at present,which cannot effectively encourage emerging entities to participate in market competition,and is not conducive to further promoting the reform of the electricity market on the retail side,so it is urgent to study and explore new market trading strategy mechanism.Based on the cooperative game theory,this paper studies the P2P(peer-to-peer)power trading strategy mechanism among the emerging trading entities in the distribution side,which has extremely important theoretical and practical reference value for improving the economic benefits of the market entities,enhancing the enthusiasm of the entities to participate in the market competition and promoting the steady and orderly progress of the reform of the power market in the distribution side.The work of this paper is summarized as follows:First of all,the paper introduces the P2P power trading system model of distribution side under multi-entities participation,including distributed P2P trading system structure model,LA benefit model,MGO benefit model and social maximum benefit model.In the system structure model,not only the specific trading framework of distributed P2P power is established,but the network loss in the process of P2P power trading is considered.Moreover,the importance and necessity of considering the problem are analyzed.In the benefit model of LA and MGO,the benefit function of each entities,the operation constraint of controllable adjustable unit in the market entities and the power balance constraint of the whole entities system are established respectively.Based on the benefit models of LA and MGO,this chapter further establishes the social benefit maximization model of distribution side.Secondly,this paper analyzes the common interests and conflicts in P2P power transactions between market entities,and proposes to use Nash bargaining solution(NBS)to settle power transactions.This settlement method can distribute the extra profits brought by cooperation fairly,and maximize the social benefits while making the market entities obtain Pareto optimal benefits.In this paper,the algorithm of alternating direction method of multipliers(ADMM)is used to solve the P2P power transaction of the market entities in a distributed iterative way.In this process,only the expected power transaction information needs to be exchanged between the market entities,so as to reduce the communication burden and protect the privacy of the entities.This strategy is verified by simulation in a 12×12 km~2distribution network,and the simulation results show that the strategy is correct.Finally,this paper further considers the specific grid structure of the distribution system in P2P power trading,and proposes a day-ahead two-stage optimal scheduling strategy.The first stage is the active power optimization stage,in which the market entities carry out P2P power transactions through the Nash bargaining theory,and optimize the active variables of the market entities;the second stage is the reactive power optimization stage.On the basis of the first stage optimization,with the objective of minimum network loss of the distribution network system,the specific network power flow structure of the distribution network is considered,and the power flow based on distflow is established The second-order cone optimization is carried out to optimize the reactive power unit in the market entities and the reactive power compensation device in the distribution network.The simulation results show that the strategy is correct in the modified IEEE33 node radial network.