Research On Optimal Scheduling Of Virtual Power Plant

It has been a strategic choice for all countries in the world to solve the problem of depleting fossil fuels,coping with the deterioration of environmental ecology and meeting the growing energy needs to vigorously exploit and utilize renewable energy sources.Meanwhile,with the rapid development of grid integrated renewable energy sources like wind and solar,many grid integrated operation problems appear and the electricity market reform is more and more urgent under the background of smart grid.Therefore,the effective organization and management of grid integrated renewable energy sources is put on the agenda.Virtual power plant(VPP)is an effective technological form for integrated management and participation in electricity market of distributed energy resources(DERs).This paper discusses the power coordination and optimal scheduling of virtual power plants based on analysis of its components.Firstly,the VPP is outlined and a physical model of the VPP with renewable energy sources such as wind and storage is established.Because VPP power uncertainty problem not only brings a challenge to internal operation itself but also poses a threat to good service provided to the system,corresponding incentive mechanism is established,namely,contract default penalty,wind and sunlight abandonment punishment and interruptible load(IL)reward-punishment,by analyzing power uncertainty of VPP market contract implementation,random power generation output and IL response.A coordinated VPP dispatch strategy is developed and a VPP optimal scheduling model is established,taking into account economic and risk benefits of VPP based on the reward-punishment mechanism.Secondly,the power component model of VPP is built,and the conventional interruptible load is promoted to a graded interruptible load(GIL),which was a more accurate and practical model;then the environment costs conversion model of VPP and conventional power plant(CPP)was established taking into account the environmental benefits of VPP;next the day-ahead two layers CPP&VPP unit commitment model was formulated with objective function of the minimum cost of the total power generation system and the maximum profit of some VPP respectively,considering the environmental benefits of VPP and the GIL established in the previous section.Finally,VPP is introduced to manage the DER as an agent,and the external characteristics of the VPP are established based on the component characteristic analysis.Then,based on the hotspot of the economic/environmental issues faced by the current power industry,the environmental/economic dispatch quardratically constaint quardratic programming model is established between CPPs and VPPs,considering the pollutant emission constraint.Next,the functions of CPLEX optimization engine and YALMIP software package are briefly introduced respectively,and the model is solved by adopting the way of modeling and solving separately.