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This post was last edited by Jibao NARI – Microcomputer Protection – Islanding Prevention – Zhang on 2020-2-20 at 19:15. An overview of the distribution network automation terminal DTU is as follows: It utilizes modern computer technology, remote control, automatic control, communication systems, as well as advanced distribution equipment to enable online and offline remote monitoring of the distribution network, as well as automated management of it. This approach aims to ensure the safe, reliable, economical, high-quality, and efficient operation of the distribution network. It features flexible configuration capabilities, WEB publishing functionality, and an independent protection plugin. It is a new type of distribution network automation terminal that integrates DTU, line protection, and communication equipment management. The functional modules of the distribution network automation terminal DTU can monitor in real time operational and fault-related information such as line voltage, line current, zero-sequence current, and device status for 10–35 KV lines. It also enables remote signaling, remote measurement, and remote control functions, thereby facilitating real-time monitoring of distribution network automation. The protection function of the distribution terminal DTU enables local detection and isolation of line faults. Adopting a distributed design pattern, it features powerful software and hardware configuration capabilities. It not only meets the real-time requirements of DTUs but also provides data storage and recording functions. Additionally, it enables independent configuration of line microcomputer protection, successfully addressing the issue of coexistence among measurement and control, protection, and communication functions. Main functions: 1. Collect line fault information to enable fault identification. 2. Execute remote control commands to achieve fault isolation and power restoration. 3. Enable the measurement and acquisition of voltage, current, active power, reactive power, power factor, frequency, or harmonic values for multiple circuits, as well as the transmission of these values to higher-level devices. 4. Receive and execute remote control commands from higher-level devices, as well as send back verification signals. 5. Receive and execute timing synchronization commands. 6. It features program self-recovery and device self-diagnosis functions. 7. It has a channel monitoring function. 8. It can be connected to multiple power sources and will automatically switch over seamlessly in the event of a failure of the main power supply. 9. It can communicate with other systems in the substation to exchange information. 10. It has the function of receiving and executing reset commands. 11. It features intelligent battery maintenance functionality. 12. It has the capability to communicate with two or more master stations. 13. Supports various communication methods such as telephone dialing, wireless, fiber optic, Ethernet, RS232/485, etc. 14. It offers a rich variety of communication protocols, supporting all currently popular protocols (such as 101, 104, CDT, MODBUS). Application scope: Distribution automation terminals DTU are generally installed in conventional substations, outdoor small-scale substations, ring main units, small power stations, box-type substations, etc. They are used to collect and calculate data such as the position signals of switching equipment, voltage, current, active power, reactive power, power factor, and electrical energy. They enable the operation of opening and closing switches, and help to identify faults in feedline switches, isolate them, and restore power supply to areas that are not affected by the fault. Some DTUs also have the functions of protection and automatic switching to a backup power supply. Functions achieved: 1. Improve power supply reliability ； 2. Improve power quality ； 3. Save energy and reduce losses, optimize operations, and improve the economic efficiency of power systems ； 4. Improve the modernization level of distribution network management.