The Design And Implementation Of Intelligent Micro-Grid System In An Island

In recent years,fossil energy crisis is increasingly serious,the traditional thermal power will face the test of depletion of resources,while thermal power emissions of large amounts of carbon dioxide,has brought serious environmental problems.At the same time,large power grids in the early part of this century have undergone several large-scale blackouts,and the power grid operation and maintenance is difficult,and it is difficult to meet the growing demand for power quality of users.Large power grid in the military is also easy to become the target,once the attack,resulting in power system power failure,power-dependent facilities will be paralyzed.The proposed microgrid provides a new way to solve these problems.Microgrid integrated distributed power,energy storage unit,coordinated control to become an autonomous system,both with large power grid for energy exchange,can also be independent of the system to provide power for the load.We want to carry out micro grid technology research,the urgent need to rely on practical engineering.Based on this,this topic began to design a island micro-grid system.First of all,the subject of the island micro-grid for the overall program design.This paper introduces the current electricity supply situation of the island microgrid and analyzes the demand of power supply,and compares the merits of AC microgrid scheme and DC microgrid in the project implementation site respectively.This paper analyzes the advantages of the hybrid microgrid with mixed energy storage in this project,and selects the equipment in the island microgrid,and determines the overall design scheme of the island microgrid.Secondly,the design of the converter in the microgrid.In this paper,the five converters in the subject are divided into three types,and these three types of converters are designed from the aspects of topology design and internal selection of main components.The converteris a key device for microgrid control.The structure of the converter control module is introduced,and the realization method of the detection and driving of the control module of the converter is given.Thirdly,a coordinated control strategy of distributed power generation unit and hybrid energy storage in island microgrid is proposed.A control strategy based on DC bus is proposed,the control mode of each converter running under this control method is described respectively,and realize unmanned operation.Subsequently,the island microgrid monitoring system based on MCGS was built.Not only to achieve the data display,curve and report output,fault records and other functions,the coordination control method will be embedded in the monitoring system to achieve the island micro-grid intelligent unattended.At last,experimental validation of this system is undergone and the practicability of the system is proved.Display output curves fluctuations in off-grid mode,and the fluctuation of the output curve is displayed when the grid mode and the off-grid mode are switched.The experimental results show that the system can run stably.