Research On Operation And Control Of Wind Storage Isolated Network System

With the rapid development of the world economy,the energy consumption is increasing,and the world energy crisis is becoming more and more prominent.At the same time,the environmental problems caused by the consumption of primary energy such as coal and oil are also increasingly prominent.Global environmental problems and energy shortages have become an important problem in the process of world history.The development of environmentally friendly renewable energy has become the first way to solve the energy crisis and environmental pollution in all countries of the world.In the efficient use of renewable energy technology,wind power is the most mature technology,the most developed conditions,good prospects for development of the project.Since 1990 s,the annual growth rate of wind power has kept the percentage of two figures.But the wind turbine output with spatial dispersion,strong fluctuation,intermittent,low inherent defects of scheduling,resulting in wind farm grid after the operation modes of power grid voltage and reactive power control,power quality and the two aspects of system influence.The technical level of the grid difficult and abandon wind has been the biggest problem restricting the development of wind power.In view of the technical problems,experts and scholars at home and abroad put forward the application of wind storage combined power generation technology to solve the problem.The energy storage system can realize the time and space shift of electric energy,and the response speed is fast and has the feasibility of large-scale application.As an effective utilization form of wind storage combined generation system,wind storage isolated network system has the characteristics of flexible operation and high efficiency.It is an important application form and technology development trend of new energy in the future,and the prospect of large-scale application is broad.Research on wind storage isolated network system operation and control technology,not only promote the development and application of clean energy technology and energy storage technology,but also to solve the supply problem in rural areas,improve the power grid operation and control flexibility,enhance the blackout recovery capability of power grid has a positive and practical significance.At present,the research on wind storage isolated network system is mainly focused on control strategy analysis and experimental verification.There is a lack of systematic theoretical proof,and many problems need further exploration and improvement.Therefore,this paper focuses on the stable operation mechanism of the wind storage system and the coordinated control strategy,and carries out the theoretical research of the wind storage isolated network system.The main work and conclusions are as follows:(1)The typical structure and application scenarios of wind storage isolated network system and the key technologies of operation and control of wind storage isolated network system are summarized.The key points for future research of wind storage isolated network system are summarized.(2)Based on the multi agent technology,the coordinated operation control strategy of the wind storage isolated network system is proposed.Based on the wind storage system coordination of isolated network operation control strategy of multi agent technology in the upper body,lower intelligent coordinated control unit decentralized control agent,through the upper coordinated interaction and response process control agent and the lower unit of decentralized control agent to achieve energy storage unit of charge / discharge control and voltage stability control in order to ensure the coordinated operation of wind storage isolated network system.(3)According to the control strategy and mathematical model of each unit wind storage isolated network system,a small signal model of the wind storage isolated network system is established.According to the eigenvalue analysis and lyapunov criterion,small signal stability analysis of wind storage isolated network system is analysised,and the approximate range of the control parameters for maintaining the stable operation of the system is obtained and the preliminary optimization is carried out.The characteristic values of the preliminary optimized control parameters are compared with the eigenvalue memory before optimization,and the simulation verification is carried out.(4)On the basis of eigenvalue analysis method and lyapunov criterion,the capacity configuration of wind storage isolated network system is analysised.Based on the MATLAB/Simulink software,under the condition of certain output of wind turbine,the capacity allocation of wind storage isolated network is simulated by changing the capacity of energy storage unit.Under the condition of certain wind turbine output(25kW),the rated capacity of the storage battery is 1000 Ah,which can not only meet the response speed of the system frequency,but also guarantee the response speed of the active power of the system.The research results of this project can provide the key technology and practical basis for the research on the stable operation mechanism and coordination control of wind storage isolated network system.