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This post was last edited by chenjinfeng on 2020-3-27 at 14:24. Distribution network automation is an important technical approach for further reducing the time required to restore power supply after failures in distribution networks and for improving the level of management of their operation. Concept of distribution network automation: Distribution automation relies on the primary power grid structure and equipment, and makes use of computer and network technologies, communication technologies, as well as modern electronic sensing technologies. With the distribution automation system as its core, it enables the integration of real-time, near-real-time, and non-real-time data from distribution network devices, thereby facilitating monitoring, protection, and control of the network’s normal operation as well as in the event of accidents. A distribution automation system consists mainly of a main station, distribution automation terminals, and communication channels; communication between the main station and the terminals is typically carried out via fiber optic cables or wireless methods such as GPRS. Significance of distribution network automation: By implementing distribution network automation, real-time monitoring of the operating status and power flow of distribution network equipment is achieved, providing strong technical support for the centralized and standardized management of distribution network operations. By rapidly locating/isolating distribution network faults and restoring power to the non-faulty sections, it reduces the scope of the fault’s impact, accelerates fault resolution, shortens the duration of power outages, and further enhances power supply reliability. Basic knowledge of distribution network automation: Feeder automation refers to the monitoring and control of the operating status of distribution lines, enabling rapid and accurate identification of faults once they occur, as well as quick isolation of the faulty sections in order to restore power supply to the areas that are not affected by the fault. Feeder automation includes two types: centralized main station feeder automation and local feeder automation. Centralized feeder automation at the main station: This refers to the communication between the distribution automation main station and the distribution automation terminals, with the main station being responsible for locating faults in the distribution lines, isolating those faults, and restoring power supply to the areas that are not affected by the faults. Local feed automation: It refers to a system that does not rely on communication with the distribution automation main station; instead, it utilizes on-site automated switches and terminals to carry out real-time detection of faults in distribution lines, enabling rapid fault location/isolation as well as the restoration of power supply to areas that are not affected by the fault. Based on control logic and operating principles, they are further divided into adaptive composite type, voltage-time type, and voltage-current type. Distribution automation master station: The distribution automation master station serves as the monitoring, control, and management center for the entire distribution network. It is responsible for collecting, processing, and storing information related to the distribution network, as well as conducting comprehensive analysis, calculations, and decision-making. It also shares information and interacts in real time with systems such as distribution network GIS, distribution network operation information systems, dispatch automation systems, and metering automation systems. Based on the layout of its functional modules, distribution automation master station systems can be divided into two types: basic Type and integrated Type. The basic distribution automation master station mainly deploys a basic platform, SCADA, and feeder fault handling modules. The integrated distribution automation master station builds upon the basic distribution automation master station system by adding grid analysis functions such as network topology, feeder automation, power flow calculation, and network reconfiguration. Distribution automation terminal devices: Distribution automation terminals refer primarily to those devices that are installed in switchyards, distribution rooms, ring main units, box-type substations, and pole-mounted switches; they are used to collect information on operational faults in distribution equipment and to carry out control functions. Depending on the application scenario, they are divided into distribution automation terminals (DTU) for substations, feeder automation terminals (FTU) for overhead lines, cable-type fault indicators, and overhead-type fault indicators. Overhead line feeder automation terminal (FTU): The overhead line feeder automation terminal (FTU) is used for the monitoring and control of sectionalizing switches and tie switches in 10kV overhead lines. It can be configured in two operating modes according to the control logic: current-based and voltage-time based. Distribution automation terminal (DTU) in the substation: The station terminal DTU is generally installed in conventional switchgear rooms, ring main units, small substations, box-type substations, etc. It is used to collect telemetry and telecommunication data related to switching equipment, to operate the switches for opening and closing, as well as to identify faults in feeder switches, isolate them, and restore power supply to the areas that are not affected by the fault.