Method of fault isolation and self-healing for electric distribution network

Abstract

The invention relates to a method of fault isolation and self-healing for an electric distribution network. The method comprises the following steps: 1) non-path protection which is capable of detecting and removing any position and does not need path relation is adopted on the electric distribution network; 2) a circuit breaker capable of cutting off short circuit electricity is adopted to replace the existing load switch; and 3) a spare power supply automatic input unit is arranged on the electric network. Compared with the prior art, the method provided by the invention does not only rely on a communication channel, can be used for removing a fault section selectively and rapidly, but also the power supply at a non-fault section can be recovered rapidly, and the power distribution network has a fault self-healing capability.

Description

technical field [0001] The invention relates to a distribution network, in particular to a method for fault isolation and fault self-healing of a distribution network. Background technique [0002] The traditional three-stage current protection and distance protection, due to the short feeder, are often difficult to achieve coordination performance; the closer the directional overcurrent protection is to the power supply end, the longer the action time is, and when the number of feeder sections increases, the action time is also unacceptable to users; However, the differential protection that performs well in the high-voltage power grid encounters difficulties on the feeder line, because the feeder line has many branch lines, and the branch currents of these branch lines are uncertain and changeable, and it also needs channels; the direction comparison type longitudinal connection Protection has a similar problem. The non-communication protection that has appeared is based ...

AI Technical Summary

Problems solved by technology

[0003] However, the disadvantages of the non-channel protection proposed at present are: the three-phase symmetrical fault cannot be removed quickly; the fault detection criterion of the passive end needs to be improved; the realization of the system also requires the cooperation of a switching device

This mode has a high level of automation, and the switch only needs one action, but it is too dependent on the channel; because the system decision-making command is issued by the dispatch center, coupled with the delay of the communication channel, the recovery time of the non-faulty section is also long ; System reliability directly depends on channel reliability

To sum up, the feeder automation technology that has emerged has the following defects: 1) Generally, except for the circuit breaker at the outlet of the feeder, other positions of the feeder are installed with load switches that do not have the ability to cut off the short-circuit current, so the non-faulty feeder section cut off is inevitable

2) The current quick-break protection is only configured at the outlet of the feeder, which will inevitably act blindly and cut off the entire feeder, without selectivity

3) Feeder automation mode relying on communication channels, complex system structure and low reliability

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