Intelligent diagnosis method and apparatus for power transmission and distribution line state

Abstract

The invention relates to a transmission and distribution line state intelligent diagnosis method and a device thereof. When the transmission and distribution line suffers from a short circuit fault, a circuit breaker trips to trigger a control device, a closing circuit is locked immediately, a line state sensor is started to detect the insulation state against ground of each phase, i.e. the rehabilitation conditions of the fault-phase insulating resister Rm of the transmission and distribution line are detected, the fault-phase insulating resister Rm is compared with the set insulation value Rj, and when the Rm is smaller than the Rj, the closing circuit is continued to be locked; and when the Rm is larger than the Rj, the closing circuit is switched on. The transmission and distribution line state intelligent diagnosis device comprises a main controlling unit, a comparison controller and a line state sensor. The invention relates to the transmission and distribution line state intelligent diagnosis and the device with a simple and compact structure, low cost, good reliability, convenient installation, simple and easy operation and better security.

Description

technical field [0001] The invention mainly relates to the field of fault diagnosis of power transmission and distribution lines, in particular to an intelligent diagnosis method and device for the state of power transmission and distribution lines, and is particularly suitable for intelligently diagnosing whether the power transmission and distribution lines can be closed. Background technique [0002] Automatic reclosing has decades of operating experience in the power system. While automatic reclosing has brought huge economic benefits, it has also brought some adverse effects to the power system. The main performance is that the automatic reclosing switch cannot distinguish between self-recoverable faults and non-self-recoverable faults. Self-recoverable faults are some faults. When the grounding short circuit is eliminated, the line insulation will automatically recover. For example, lightning strikes an overhead line tower to trip the line. The line insulation will not...

AI Technical Summary

Problems solved by technology

[0005] 1. First put forward the voltage criterion and the voltage compensation criterion. This method mainly uses the characteristic that there is a capacitive coupling voltage when a transient fault occurs in the fault phase, but there is no such voltage when a permanent fault occurs to distinguish permanent faults from transient faults. , its main shortcoming lies in its low sensitivity, and its ability to withstand transition resistance is at the expense of the applicable length of the line and is affected by the operating mode of the system

[0006] 2. Some scholars use artificial neural network (ANN) technology to identify permanent faults and transient faults. Although this method has high precision, training neural networks requires a lot of fault calculations, which is complicated to implement and difficult to apply to actual system

[0007] 3. The proposed digital signal processing algorithm for identifying transient and permanent faults using the characteristics of arcs in the air, but it is very difficult to establish an accurate arc model, and due to the differences in the characteristics of different types of arcs, this method is universally applicable restricted

[0008] 4. In recent years, some researchers believe that the high-frequency signal generated by fault transient can be used to identify permanent faults and transient faults, but it is difficult to identify permanent faults and transient faults because high-frequency signals, especially high-frequency signals of voltage collection

This greatly affects the power supply reliability of the distribution network and affects the safe and stable operation of the distribution network.

It makes it impossible to effectively distinguish the fault category, which greatly affects the stability and reliability of power production

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