| With the continuous development of distributed energy technology,Micro grid as a new type of distributed energy,provide technical support for the effective use of new energy.Due to the intermittent and random nature of distributed power generation,connecting it to the grid will worsen the stability of the power system.Microgrid is used to manage the distributed energy and energy storage system to improve the stability and economic benefits of power system operation.Compared with AC micro grid,DC micro grid is more efficient and reliable in the use of distributed renewable energy generation systems such as wind and water and the load of DC electricity.It is of great significance to the sustainable development road and can be more effective.To promote energy conservation and emission reduction.The isolated island DC microgrid can effectively solve the problem of power difficulties in remote areas and islands.In order to meet the requirements of long-term stable and effective operation of DC microgrids in remote areas and islands,it is the requirement of low energy loss and high economic benefit.In this paper,an energy storage system control strategy of wind and hydro power complementary microgrid system is studied,which can improve the power generation efficiency and stability of the system more effectively.The energy storage battery control strategy in the wind and hydro power complementary microgrid studied in this paper is based on the target site being an industrial park with distributed energy,combined with the power supply characteristics of the industrial park,the wind turbine is used as the fast power supply reserve micro-source,and the battery is used as the micro-source to adjust the fluctuation of power grid quickly.By controlling the instantaneous output of the battery,the problem of poor power quality of micro grid can be solved.The main work of this paper is as follows:Firstly,the structure design of microgrid system used in remote area is carried out,the working principle and mathematical model of wind power and hydro power are analyzed,and the wind power model and runoff hydro power model are built based on MATLAB/Simulink,and the operation of wind power model and runoff hydro power model in different conditions are simulated by simulation.Secondly,based on the introduction of wind power model,the method of maximum power point tracking is proposed.Through the analysis and comparison of different methods,the gradient disturbance observation method is selected to track and control the maximum power point of wind power generation,and the feasibility of the control strategy is verified by simulation analysis.Finally,the energy storage system control strategy for stable operation of microgrid system is designed.compared with the control strategy and V/f control strategy of PQ-V/f combined control based on charged state,it can make full use of wind power and hydro power resources without causing overcharge and over discharge of energy storage battery,and better protect the energy storage battery.The LLCCL filter is used to ensure that the micro-grid system can supply and distribute power for this kind of area stably.And the MATLAB / Simulink simulation software was used to analyze the proposed control strategy to verify the feasibility of the control strategy in the case of this industrial park. |
PDF Full Text Request