The Optimal Dispatch Of The Power System Containing Virtual Power Plants Under The Background Of Energy Conservation And Emission Reduction

With the growing demand for energy over the world,fossil energy resources are on the verge of exhaustion,and the ecological environment gradually deteriorates.The idea of energy conservation and emission reduction(ECER)has attracted more attention,and the call for using clean and renewable energy has improved.As a large fossil energy consumer,the power industry shoulders the responsibility of ECER.The increasingly serious fog and haze(F-H)problem of China and the optimal dispatch puzzles caused by a large number of clean distributed energy resources(DER)connectting to the power grid directly,have brought challenges to the power system security,green and economic operation.On that basis,this paper discusses the problem of the optimal dispatch of the power system containing virtual power plants(VPPs)under the background of ECER.First,the impact of F-H on photovoltaic output and load is discussed according to the increasingly serious F-H environment in China.The idea of similar days of F-H has been proposed to deal with the photovoltaic output and load forecasts considering F-H.The wavelet neural network(WNN)model is employed to realize the prediction.The results show that the prediction precision could be improved by adding the factor of F-H.Secondly,in view of the dispatch puzzles caused by a large number of DER connecting to the power grid,the concept of VPP is introduced.A VPP containing various DER without geographical restriction is built and the cubic exponential smoothing method is adopted to predict its load requirement.The optimal configuration of DER capacities inside the VPP is calculated by the portfolio theory and the genetic algorithm(GA).A static combinated operation strategy of VPPs is proposed to handle the coordinated operation of VPPs,which is also calculated by the GA.The case analysis has provided a feasible reference for the planning and operation of VPPs.Finally,an optimal dispatch model of the power system containing VPPs under F-H weather is constructed,where the growth factor function of pollutant cost that counts in F-H is put forward and integrated into the emission cost.The cost disadvantage of the VPP is offset through the financial subsidies.The model is transformed into a mixed integer linear programming(MILP)problem by linearization processing and solved by Yalmip toolbox of Matlab.The conclusions of the example show that the proposed model and algorithm can effectively improve the absorption of DER in the F-H weather,and achieve the goal of ECER while taking into account the economic benefits.