Research On The Economic Operation Model Of Virtual Power Plants In The Smart Grid

In recent years,with the increasing serious issues of energy and environment,the power industry as a high-energy-consuming one continues to accept more criticism.In the new situation,the development of renewable energy generation(wind power,photovoltaic power generation,etc.),as well as Distributed Generation(DG)connected to the grid,is an important mean to solve the issues of energy,transport,environment,in line with the world national strategies for sustainable development needs.However,a lot of intermittent renewable energy generation connected to the grid,which will brings new problems of security and economic operation.In order to ensure the safe operation,improving operational efficiency of the power system has become the core issue of widespread concerned.Therefore,in order to make more effective use of these distributed generation resources,the concept of virtual power plants(VPP)is introduced.To solve the large number of optimization scheduling problem,which is distributed generation of geographical dispersed and small capacity,the concept of virtual power plant is introduced considering the uncertainty of maximum output of wind power,photovoltaic,micro-cogeneration distributed generation and so on.The output of distributed generation will be predicted based on the optimization algorithm of artificial neural networks,game theory,mixed-integer linear programming algorithm and so on,to analysis the optimization of operation scheduling of internal resources and economic operation of VPP under the smart grid environment.At last,the operational mechanism of VPP in the electricity market is analyzed,with a new method is proposed to take part in the power system dispatch and market competition based on the uncertainty of the output in the VPP of distributed generation.Firstly,the characteristics of DG available in the VPPs are predicted and analyzed.To solve the output uncertainty of wind power,photovoltaic(PV),micro-cogeneration units,the random nature of wind power is described.Considering the correlation probability of maximum output in the windy field,a joint probability distribution of the maximum output in the windy field is built with the Gumbel-Copula function.Similarly,the prediction model of PV generator and micro-CHP unit power curve is analyzed,to build the power unit combination predict model.Secondly,the scheduling output power of distributed power,fuel,generators,energy storage devices and interruptible load is optimized with VPP concept,to achieve aggregation and management of DGs,which has capabilities similar to conventional power plants to participate in the electricity market trading and scheduling systems.In an scheduling object of distributed power output,under the premise of maximizing the use of wind power output,meeting the operating constraints of network security,and distributing power supply capacity constraint,aiming at the maximum of the expected economic benefits of the VPP,an optimization scheduling model of DGs is proposed about internal VPP based on artificial neural network(ANN).The improved algorithm of ANN training set is built based on MINLP and ANN algorithms,and through a moderate amount of computation,the value of the objective function of minimum energy supply costs and LMP in the power system are calculated.Then,the results of improved ANN algorithm are compared to the one of directly MINLP algorithm,with the conclusions are summarized that the cost of the improved ANN algorithm is lower with a shorter calculation time,and the results are also better.Thirdly,the economic running model of VPPs taking part in the market transactions under smart grid environment is analyzed.The game theory is used to analyze the VPP mechanisms for the electricity market and several possible trading patterns,making appropriate market trading mechanism model combined research experience home and abroad,and further analysis of the operating environment of current distributed generation of transactions involved in the electricity market.The self-organizing mechanism of collaborative VPPs is proposed,to build a regulatory model of VPP to participate in economic power market transactions.Finally,trading,auction and operation mechanisms of VPP operating in the electricity market are analyzed,with the energy-saving equipment taking into account.By studying the subject of all kinds of power-related mechanisms involved in the electricity market under the background of electricity market reform,a trading model of VPP involved in the electricity market is built,and a unified national electricity market model is found to develop the bidding strategies of VPPs participating in the unity electricity market.The differential pricing mechanism is analyzed combined with the transformation of high energy-consuming equipment,to optimize the mechanism of VPP operating mechanisms based on the second floor theory,and the comprehensive benefits are analyzed.Conclusions show that the introduction of energy-saving equipment in the traditional high-energy device,as integration of VPP resources,can greatly improve the promotion of the VPP feasibility,and promote energy conservation and energy environment.To sum up,the concept of VPP is introduced in this paper,and based on the economics,operations research,statistics and other disciplines theory,the problem of optimal scheduling of DGs in VPPs under the smart grid environment and the economic model of VPPs involved in the regulation of the electricity market transactions are analyzed,with the mechanisms of VPP operation in power trading under the electricity market reform background described,to provide a theoretical reference to the large-scale distributed generation resource with the characteristics of small capacity,geographically dispersed,uncertainties and other characteristics.