Research On Internal Pricing Mechanism Of Virtual Power Plants Considering Double Uncertainty Of Source And Load

With the large-scale access of new energy with intermittent,random,and volatile characteristics to the power grid and the electricity market-oriented reform entering the’deep-water zone’,the power system will confront greater challenges.As a small energy autonomous system that aggregates distributed electricity generation,energy storage,and load,virtual power plants(VPP)not only connect the power market and end users,but also are an important subject of electricity market-oriented reform.Their operational efficiency directly determines the success of market-oriented reform.However,during the operation of VPP,they are faced with market risks on account of the dual uncertainty of internal renewable energy output and load demand,and need to optimize market behavior to safeguard their own interests.Therefore,this article takes VPP as the research object,and discusses the internal pricing strategy of VPP considering the dual uncertainty of source and load and real-time market linkage from the aspects of theoretical analysis,system modeling,and model validation,thereby providing a reference for actual market-oriented policy formulation and internal pricing decisions of VPP in different market environments.The main research contents of this article are as follows:The first is to analyze the source and load uncertainty of VPP and their main characteristics;The second is to analyze three internal pricing mechanism rules of VPP:the transaction mechanism of ’spontaneous self use,surplus(shortage)sale(purchase)’by prosumers,the compensation mechanism of virtual power plant operators(VPPO)for energy storage,and the compensation mechanism of VPPO for flexible loads;On the basis of constructing profit functions for producers and consumers,flexible loads,and VPPO,a two-layer two-stage internal pricing model considering source load uncertainty was designed.The thirdly is to validate the model through example analysis and further explore the impacts of flexible resources and spot market prices on pricing.The main conclusions are as follows:(1)Through the internal pricing method for VPP proposed in this article,virtual power plant operators can fully utilize the spot market to achieve arbitrage and hedge,avoid risks brought by the uncertainty of wind power output and flexible load demand,increasing the benefits of VPPO,prosumers,flexible loads,and other entities participating in the electricity market,verifying the effectiveness of the model(2)Source uncertainty has a greater effect on the internal pricing of VPP.When the load is uncertain,virtual power plant operators can achieve their own energy balance by setting compensation prices for energy storage.However,when the source is uncertain,they need to further dispatch flexible loads to partake in demand response,and virtual power plant operators will establish higher internal power selling prices to compensate for their losses in purchasing power in the real-time market.(3)Spot market prices are positively correlated with the three internal prices established by VPP.Nevertheless,with the rise in external market electricity prices,the scheduling of VPP will become more dependent on the demand response of flexible loads.