Research On Locational Marginal Price Manipulation By Renewable Energy Generation Aggregators In Power Markets

In 2015,the No.9 document issued by the CPC Central Committee proposed the orderly opening of power generation and utilization plans other than public welfare and regulatory ones;in 2019,it proposes to fully liberalize the power generation and utilization plan for operating users,promote the access of renewable energy such as wind power,optoelectronics,etc.to the power market;in the same year,China State Grid Co.,Ltd.proposed the idea of building a ubiquitous power Internet of things,which brought new changes to the energy field and technical support for the integration of power resources by renewable energy generation aggregators.Renewable energy power generation aggregators have been applied in foreign power market,mainly used to integrate small scale market entities such as solar power generation for transactions.The introduction of aggregators can not only reduce the transaction costs of market entities,but also manage market risks to a certain extent,which is worth learning from in China’s power market.However,with the introduction of renewable energy power generation aggregators,the node marginal price(LMP)in the power market is facing the risk of being manipulated,thus disrupting the order of the power market.Therefore,it is an urgent problem for the power market to study the impact of renewable energy generation aggregators on the marginal price of nodes and formulate reasonable market response strategies.This research is divided into two parts: the operation of renewable energy generation aggregators on the node marginal price in the electricity market,and the effective response strategies that independent system operators(ISO)can adopt.Aiming at the problem of controlling electricity price of renewable energy generation aggregators,the research includes: the trading framework of electricity market after the introduction of aggregators into China’s electricity market;the formation process and calculation model analysis of node marginal price in electricity market;analysis of potential illegal trading behavior of renewable energy generation aggregators;and the strategy analysis of renewable energy generation aggregators to control the node marginal price by reducing the generation in the power market for the purpose of profit.In this paper,a nonlinear programming mathematical model is established by using the idea of three-level programming,which takes the maximum revenue of renewable energy generation aggregators as the upper goal,the system economic dispatch as the middle level,and the calculation of the marginal price of system nodes as the lower level.In view of the effective strategies that independent system operators can adopt,the research includes: using stochastic programming method and robust optimization method to analyze the reduction strategies of renewable energy generation aggregators;this paper puts forward the strategies that can be adopted by independent system operators,and establishes a mathematical optimization model aiming at minimizing the fluctuation of system price.The results of an example prove the validity and rationality of the model.The first example shows that renewable energy generation aggregators can control the system node marginal price and make profits by reducing the generation capacity.When the system operators adopt different economic scheduling schemes,the maximum profits of aggregators are different.The second example shows that the independent system operator can keep the system price stable by adding generator in the power system.