Research And Solution Of Optimal Scheduling Problem Of Virtual Power Plant

With the rapid development of new energy and demand-side response technologies,renewable energy and flexible demand-side response loads are connected in large quantities,which has a significant impact on power grid security and dispatching.Since renewable energy is stochastic and difficult to control,its large-scale expansion will affect the security and stability of power grid.However,Virtual power plant(VPP)can effectively reduce the impact and improve the safety of power grid.VPP integrates renewable energy dispersed in different geographical locations,equips with energy storage systems of specific capacity,traditional power plants and demand response resources,and participates in power market and power grid operation as a virtual whole,so as to achieve complementary advantages of multi-form distributed resources and improve overall income.However,there are still some problems in the optimization of VPP scheduling,such as the scale of distributed resources,the security of distribution network and the uncertainty of renewable energy output.Therefore,it is of great significance to study and solve the problems in VPP optimal scheduling.The research contents of this paper are as follows:1)In view of the large scale and variety of distributed resources in VPP,this paper studies the power consumption characteristics of cluster resources,equivalents cluster electric vehicles and cluster air conditioners to the standard form of "battery",quantifies the scheduling potential of these resources,and establishes a virtual energy storage model.It not only reduces the computational dimension and complexity of optimization solution,but also protects the privacy information of users and increases the visualization of scheduling management.2)As the VPP economic scheduling model does not consider the security of the distribution network,this paper adopts the non-cooperative game method to establish the VPP non-cooperative game model.This model can consider both the economy of VPP and the security of distribution network.The effectiveness of the non-cooperative game model is verified by comparing and analyzing the ECONOMIC dispatching model of VPP,the security dispatching model of distribution network and the non-cooperative game model of VPP.3)Aiming at the uncertainty of electricity price and photovoltaic output,stochastic programming method and two-stage robust optimization are used to solve the uncertainty of electricity price and photovoltaic output respectively.A stochastic two-stage robust optimal scheduling model of VPP with virtual energy storage was established.Furthermore,the model was decomposed into main problem and sub-problem according to the key scene identification method.The main problem solved the single-layer optimization model of the objective function,and the sub-problem was used to identify the worst scene set.Finally,the effectiveness and efficiency of the algorithm are verified by the example of GAMS and MATLAB.