The Study Of Coordinated Control Method Of A Variety Of Distributed Energy Based On Virtual Power Plant Technology

Along with the rising of electric power demand,the shortage of energy resources and the intensification of climate and environmental problems,it brings great impact and risk to traditional electricity generating system.Use of a single class of thermal power plants is no longer sufficient for the demand electricity users,so load can also be used as a resource to respond to the power system.Virtual power plant as a new form of demand response technology,it integrate a variety of distributed energy in power grid,such as controllable loads,distributed generators and energy storage system.Therefore,research on virtual plant technology is important.In this paper,based on the theory of virtual power plant technology as the research background,it is important to study the coordination control strategy of air conditioning load aggregators,photovoltaic power generation system and battery energy storage system.First of all,the concept of virtual power plant and components are analyzed,the centralized control strategy of virtual power plant and decentralized control strategy is studied,the operation mechanism of virtual power plant,input and output variables of two types virtual power plant are analyzed,the intelligent measurement technology of virtual plant is introduced.Secondly,the mathematical model of virtual power plant inside each unit is established,the mathematical model of photovoltaic cell,DC/DC converter and DC/AC converter are established for photovoltaic power generation system.The thermodynamic equivalent model is established for air-conditioning load,prediction method of air-conditioning load controllable capacity are given.The characteristics of different the type of battery is analyzed,several of equivalent circuit of lithium ion battery are also analyzed.Therefore,a coordinated control strategy is studied with load aggregators and battery energy storage system,the working characteristics of the photovoltaic cells,control diagram of photovoltaic power generation system are presented,and thesimulation research is carried out.The wheel control strategy of air conditioning load is given,and the simulation research is carried out.According to the traditional method without considering distributed generation unit and load power fluctuation caused by load shifting,constant power control of the battery energy storage system is proposed to eliminate load shifting deviation.On the basis of considering the real-time price change factors,the fuzzy control strategy of battery energy storage system is proposed.Simulation research and comparative analysis are performed for without battery energy storage system,with battery energy storage system based on constant power control and fuzzy control.Finally,an intelligent monitoring and system of temperature and humidity in the ZigBee based on wireless communication technology was designed and realized.The air conditioning load can participate in the virtual peak load regulation of power grid,simulated the centralized control process of controllable load of power network in real life.