Design And Application Of AC/DC Hybrid Microgrid Monitoring And Energy Management System

A microgrid is an electric power system that can effectively integrate distributed renewable energy sources.Unlike standalone DC and AC microgrids,hybrid AC/DC microgrids reduce conversion steps and devices,enabling flexible and efficient integration of distributed renewable energy sources into the grid.This article focuses on the design of a microgrid monitoring and energy management system software specifically for hybrid AC/DC microgrids.It provides real-time and accurate data monitoring and device control,ensuring efficient,economical,safe,and reliable microgrid operation.The main contents are as follows:(1)The architecture of the hybrid AC/DC microgrid is designed,with the DC side following battery voltage changes and removing pure DC loads to reduce control complexity.The communication control system of the microgrid is divided into three layers: process layer,interval layer,and station control layer.Communication between the process layer and interval layer uses RS485 and Mod Bus-RTU protocols,while communication between the interval layer and station control layer uses Ethernet and Mod Bus-TCP/IP,achieving stable microgrid operation.(2)Traditional operational strategies for microgrids with distributed power sources,loads,and energy storage systems often focus only on the internal components’ performance and fail to consider comprehensive energy balance within the microgrid and its coordination with the external grid.Additionally,some energy management strategies are overly complex and computationally intensive,leading to decreased system stability.Therefore,this article proposes simple yet stable energy management control strategies for maximizing benefits in grid-connected mode and maximizing the lifespan of energy storage systems.In off-grid mode,load prioritization and maximizing operating time principles are proposed to optimize microgrid operation.(3)To address the problem of poor scalability in most microgrid monitoring and energy management systems available on the market,this software solves the issue by adding configuration files.This allows for seamless updates to the software without the need for recompilation when there are changes,additions,or removals of microgrid equipment.Instead,the corresponding configurations can be modified in the configuration file,and upon reboot,the software will automatically update the interface and database based on the configuration file.The software is developed using C#language on the Windows platform,utilizing the Microsoft.NET Framework’s WPF framework for microgrid monitoring and energy management.It adopts a modular design,ensuring strong code versatility and high scalability.(4)The effectiveness of the microgrid monitoring and energy management system is demonstrated based on the Nanchang University Photovoltaic and Hydrogen Energy Storage Intelligent Microgrid Demonstration Project.The installation of the microgrid monitoring and energy management system enables efficient,economical,safe,and reliable operation of the microgrid,validating the effectiveness of the energy management strategies in off-grid mode.The effectiveness of energy management strategies in grid-connected mode is verified through simulation and emulation.