Research On Optimal Scheduling Of Virtual Power Plants In The Combination Of Day-ahead And Real-time Markets

With the proposal of the ‘30.60 Emission Carbon Peak-Carbon Neutrality’ strategy,distributed resources have developed rapidly in the source,network,load and storage links of the power system due to the advantages of environmental protection,economy,reliability and flexibility.Factors such as reliability and demand-side resource uncertainty also bring challenges to the stable operation of the power system.Virtual Power Plants(VPP)integrate various distributed resources,participates in the power market and power system scheduling,and provides output services and auxiliary services such as peak regulation and frequency regulation to the power grid.It is a viable business model for sexual value to give full play to the green value and flexibility of distributed resources.Therefore,it is necessary to study the bidding strategy,optimal scheduling method and distributed collaborative architecture of virtual power plants when participating in electricity market transactions,so as to fully maximize the benefits of virtual power plants and optimize regional load characteristics.Aiming at aggregating multiple distributed resources to construct VPP to participate in electricity market transactions,the paper conducts relevant researches on resource modeling,bidding strategy,optimal scheduling and distribution coordination.First,the types and frameworks of virtual power plants participating in electricity market transactions are studied,and the internal aggregated distributed resources are modeled in detail.And then VPP bidding optimization model for joint participation in the day-ahead-real-time market is constructed.Finally,for the coexistence of multiple VPPs in the region,the introduction of Internal direct transaction balancing mechanism to build a multi-VPP distributed coordination optimization model considering regional load characteristics.The specific contents include:(1)On the basis of clarifying the concept,definition and typical control structure of VPP,the distributed resources for building VPP are modeled,and a method for establishing charge and discharge power constraints of EV clusters based on energy trajectory boundaries is proposed.Summarize the types of electricity markets that VPP participate in,and introduce the trading framework for VPP to participate in day-ahead market,real-time market and balanced market.(2)Establish the transaction framework and bidding clearing process for VPP to participate in the day-ahead market,and consider the VPP’s goal of maximizing its own revenue to establish a day-ahead market bidding model.By setting the parameters and market information of each part of the VPP,for four different VPP construction schemes,it is verified that the VPP can adjust the internal resources to adapt to the change trend of the market electricity price in the day before to achieve the growth of its own income.(3)In view of the high-yield risk problem caused by the day-ahead forecast error when VPP only participates in the day-ahead market,make VPP jointly participate in the day-aheadreal-time market,and through the short-term forecast with high accuracy and fine-grainedness in the real-time stage,the day-ahead pre-dispatch plan.Make corrections and balance electricity in the real-time market.Based on the transaction framework of day-a-day-real-time market combination,a two-stage optimal scheduling model for VPP participation in day-a-day-realtime market is established which considers system network power flow constraints in stages.At the same time,it has the effect of improving the revenue of VPP and the impact on the operation status of the distribution network system.(4)For scenarios where multiple VPPs coexist in the region and jointly participate in the day-ahead-real-time market,a direct transaction mechanism between VPPs is introduced to organize cooperation and competition among multiple VPPs with a decentralized control structure.In order to meet the goal of improving the multi-VPP revenue while taking into account the regional load characteristics,a two-stage multi-VPP distributed coordination optimization model considering the regional load characteristics is proposed based on the ADMM distributed optimization framework to ensure the privacy and security of information.In the case where there are three VPPs in the setting area of the example,the proposed model is verified to optimize the multi-VPP revenue and regional load characteristics under the premise of protecting the internal privacy information of each VPP through a distributed optimization framework.