Method and device for quickly and intelligently isolating fault in zero second in first overcurrent section of power distribution network

Abstract

The invention discloses a method for quickly and intelligently isolating a fault in zero second in a first overcurrent section of a power distribution network, which comprises the following steps that: when a certain section of a main line fails, feeder terminal devices corresponding to an in-station switch and a section switch at the upstream of the section detect a fault current, and if the fault current exceeds a set value of the current of a first overcurrent section, the in-station switch and the section switch rapidly trip in 0s; the feeder terminal devices control section switches in non-fault sections to be re-closed step by step from top to bottom according to the switch network topology, quickly identify a fault point, and switch off and lock the section switches at the two ends of the fault point, so as to isolate a fault area; the in-station switch is reclosed within a set reclosing time, and recovers power supply at the upstream of the fault point; and an interconnection switch starts closing and recovers power supply at the downstream of the fault point. A fault can be isolated between a former switch and a latter switch in a fault area, so that the fault area is minimized, power supply at the upstream and downstream of the non-fault area is recovered in time, and the automation level and the power supply reliability of the distribution network are improved to the maximum extent.

Description

technical field [0001] The invention relates to distribution network feeder automation, in particular to a method and device for quickly and intelligently isolating faults in a distribution network over a period of zero seconds. Background technique [0002] The three-stage current protection is to set different delay action times under different over-current values ​​to avoid peak currents, so that when a short-circuit fault occurs on the line, only the circuit breaker closest to the accident point operates to reduce the impact of power failure. The over-current section is also called current quick-break protection. When the over-current in the station is set to 0S protection for a period of time, the short-circuit fault current of the line exceeds the fixed value of the over-current section, which will cause the switch in the station to trip and cause a power outage on the whole line, which cannot quickly and effectively isolate the fault. The power supply can only be rest...

AI Technical Summary

Problems solved by technology

The over-current section is also called current quick-break protection. When the over-current in the station is set to 0S protection for a period of time, the short-circuit fault current of the line exceeds the fixed value of the over-current section, which will cause the switch in the station to trip and cause a power outage on the whole line, which cannot quickly and effectively isolate the fault. The power supply can only be restored after checking and repairing

Long-term power outages will bring huge economic losses and have a huge impact on power supply reliability and service satisfaction

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