Research On DC Microgrid Control And Coordination Optimization Strategy For Solar-Storage

Distributed generation technology has many advantages,such as high utilization rate of new energy,economy and reliability.With the increasing number of nodes connected to the grid by distributed new energy,the penetration of high proportion of distributed new energy brings about the stability of power system.Microgrid is the key to solve this problem.Compared with traditional AC distribution network,DC microgrid has technical and economic advantages,and has great development prospects.In this paper,the structure,operation mode and optimal coordination strategy of DC microgrid are studied.Through the study of bus structure and mathematical models of different microgrids of photovoltaic,battery and inverter,different control strategies and practical operation modes are formulated.On the basis of traditional droop control,a cooperative optimization control strategy based on multi-microgrid is proposed,which takes advantage of the dominant role of different types of power supply to act as the main role of power supply in different stages,while giving full play to the advantages of droop control without communication links,so as to maintain the stability of DC voltage and ensure the safe and stable operation of the system.Through the comparative analysis of capacity,benefit,voltage loss,economic cost and other microgrid indicators,the differences,advantages,disadvantages and future development trend of AC/DC microgrid are clarified.A simple microgrid model based on photovoltaic,energy storage and other micro-power sources is built in MATLAB/Simulink simulation,which verifies the operation and control modes of different micro-power sources.In this paper,the coordination of micro-power supply in DC power grid and the function of DC power grid in hybrid power grid are analyzed and simulated by two schemes.The simulation results verify the effectiveness and correctness of the strategy.The structure and operation mode of DC microgrid exhibition are analyzed and studied,and the optimal coordination strategy is put forward,which can be used as a reference for the stable operation of the actual microgrid.This study has certain practical significance and practical value.