Research On Related Technologies Of Intelligent Gateway In Microgrid System

With energy and environmental issues becoming increasingly serious, distributed power as a clean and efficient new generation form is taken seriously in many countries of the world. But a large number of distributed powers connected to the grid will bring security and stability risks, and therefore the concept of micro-grid is proposed. Micro-grid is mainly composed of the distributed power, protection devices, load, energy storage, monitoring systems, and energy management system, which changes the grid-connected problem of a large number of distributed powers into a controlled-source problem and reduces the adverse effects on distribution network.In the micro-grid, the sampling, communications, and protection of power supplies, loads and point of common coupling node is particularly important, so this paper focuses on the intelligent gateway applied in micro-grid system.After the description of the background of intelligent gateway, according to the actual needs of the micro-grid applications, the paper proposed three-port structure intelligent gateway, making intelligent gateway more flexible applied in the node of micro-grid, which also simplified the difficulty of micro-grid platform construction. Then this paper gave detailed explanations of the development process of intelligent gateways from both hardware and software aspects. The hardware description includes a sampling circuit, capturing circuits, communications interface circuits, and LCD monitor design, and the software highlights program design, power quality analysis and software phase lock based on FreeRTOS operating system.Islanding detection is one of the key issues in the micro-grid. After summarizes of the current situation and the advantages and disadvantages of various domestic islanding detection methods, the article proposed a novel islanding detection based on impedance pattern recognition approach. With setting up an experimental platform of islanding detection and using of MATLAB for data post-processing, the paper verified the accuracy and reliability of this kind of islanding detection method, which laid a solid foundation for the islanding detection of micro-grid intelligent gateway.