Ring differential protection method and device for distribution network

Abstract

The invention discloses a ring differential protection method and device for distribution network, which relates to the technical field of power network. The ring differential DTU device is arranged on a distribution station in a substation, and each DTU device is ring-connected through a gigabit optical fiber. The voltage and current data are sampled by a DTU device, and then a message is formedand sent out; Each DTU device sends the sampled value of the tie line and its own state information through the optical fiber ring network, and simultaneously receives the sampled value and the stateinformation of the equipment subscribed by the DTU device. When the launching fault occurs between two substations, the differential algorithm is used to trigger the differential action, and the circuit breaker of the two substations is disconnected and the fault is removed. A DTU device is use for collecting real-time data of whole line and establishing relay protection by utilizing line currentdifferential protection. That invention has the advantages of high reliability, fast operation speed, high sensitivity and good selectivity, thereby reducing power-off area and shortening power-off time.

Description

technical field [0001] The invention relates to the technical field of power grids, and more specifically relates to a ring differential protection method and device for a distribution network. Background technique [0002] With the gradual advancement of the national smart grid construction work and the gradual development of the decentralized distribution network access mode, the new distribution network operation structure and protection control technology are urgent tasks to improve the reliability and power quality of distribution network power supply. Network reliability is an important indicator to measure the power supply level of a region. When a fault occurs, the power outage area is large and the time is long. Contents of the invention [0003] The technical problem to be solved by the present invention is that when a short-circuit fault occurs in the existing distribution network, the blackout area is large and the time is long. [0004] The present invention ...

AI Technical Summary

Problems solved by technology

[0002] With the gradual advancement of the national smart grid construction work and the gradual development of the decentralized distribution network access mode, the new distribution network operation structure and protection control technology are urgent tasks to improve the reliability and power quality of distribution network power supply. Network reliability is an important indicator to measure the power supply level of an area. When a fault occurs, the power outage area is large and the time is long.

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