Research On Optimal Decision And Dispatch Of Electricity Retailers Considering Virtual Power Plant

In recent years,Chinese power market has developed rapidly.The number of medium and long-term transactions and the amount of transaction electricity in the power grid have grown directly.The market-oriented reform of the electricity sales side has achieved remarkable results.These achievements have brought new opportunities and challenges for the new subject of the electricity retailers.The basic operation mode of electricity retailers is to purchase electric energy from the power trading center through medium and long-term contracts and real-time market,and sell the power energy to users to earn difference.The power generation selling company can also reduce the cost of power purchase and increase the operating income by using its own power generation assets.However,the lack of resource integration capability on the demand side will lead to the waste of resources.The uncertainty of real-time market price and the fluctuation of user load will also bring great operational risks to the power selling companies.In order to increase the flexibility and economy of the power market participation of the power selling companies,and improve the efficiency of the power companies to use the distributed resources.Firstly,based on the aggregation management mode of virtual power plant(VPP),the operation system of electricity retailers with VPP participation is constructed.The electricity retailers can not only purchase and sell electricity in the power trading center,but also use VPP to control distributed resources to participate in optimal dispatching,and guide users to balance power consumption by price demand response.Secondly,based on the theory of master-slave game,the optimal decision model of electricity retailers and VPP is established.The main game player,the electricity retailers,takes the maximum of its own economic benefits as the objective function,the slave game player VPP takes the lowest internal dispatching cost as the objective function,and the energy of both sides is coupled to each other,and continuously transmits its own strategy and iteratively optimizes,and finally outputs the optimal operation decision.The results of the calculation show that: considering the operation system of the electricity retailers participated by VPP,the optimal decision-making is made by the master-slave game,which can make use of controllable load and distributed energy to participate in market transaction,optimize the operation strategy of the electricity retailers and improve the economic benefits.Finally,a multi-time rolling optimization model for power companies is proposed.In the early stage,the sale and sale strategy of the power companies and the daily dispatching plan of the virtual power plants are formulated according to the optimization goal of the sales company.In the day stage,higher precision distributed photovoltaic and load forecasting are considered,and the optimal scheduling model is built with the lowest scheduling cost of virtual power plant.In real time,the capacity reserve of virtual power plant is considered in the form of opportunity constraint,and the output of some units of virtual power plant is corrected,and the output of uncertain units is fed back to the daily stage for correction.The simulation results of the calculation examples show that the VPP aggregation method can coordinate the control of multiple kinds of distributed electric resources and dispatchable loads at different time scales,improve the flexibility of power purchase and sale decision,increase the operating income and improve the distributed photovoltaic consumption.