Power cable identification method

Abstract

The invention relates to a power cable identification method. The method comprises the steps of signal transmitting, signal receiving, phase calculation, alignment judgment and the like. According to the power cable identification method provided by the invention, on the basis of a double modulation wave technology, the electromagnetic induction principle is utilized, and on-line detection of the power cable is realized by identifying different phases of the coupling signal. The transmitting end couples an identification signal to a metal armor of the cable through electromagnetic induction; and a receiving end detects the signal on the metal armor and performs identification by adopting a phase identification technology so as to judge the corresponding relation between the power cables.

Description

technical field [0001] The invention relates to a power cable identification method, which belongs to the technical field of cable detection. Background technique [0002] In cities, power cables are almost always laid in underground pipes, and then pipe wells are opened on the road for equipment maintenance. There are often multiple power cables in the pipeline, and there will also be labels to identify them when they are initially laid, but after a long time, the labels may corrode and fall off. In addition, when laying power cables, most of the power cables are entrusted to external construction units to implement, technical and management. There is a big difference in the level, and the dislocation of the pipe through the upper and lower parts occurs from time to time. When crossing the fire separation wall, the communication channel, and the mixed buried section, there are often situations such as mutual entanglement and coiling; there is also a lack of standardized acc...

AI Technical Summary

Problems solved by technology

The pulse polarity method has the advantage of obvious electromagnetic field change characteristics, but it must untie the grounding wire at the end of the cable during operation, and connect the pulse signal source to the grounding system in series. However, in the safety regulations for cable operation and maintenance, It is forbidden to release the ground under operating conditions

Therefore, the pulse polarity method can only identify out-of-service cables, and cannot implement the identification and detection of running cables. Power cables are identified and detected, but if multiple cables are grounded together (currently commonly used construction method), the signal flow of each cable will change or even have no signal flow due to the difference or lack of remote grounding resistance. Misjudgment or identification is difficult, and when detecting a double bridge, the signals of the two cables are equivalent, and the target cable cannot be identified. At present, most cable identification instruments on the market basically use the audio induction method; the resistance method is simple and practical. However, due to the strong electromagnetic field environment around the cable operating environment, there are different interference errors in different detection circuits, the accuracy is difficult to control, and it is difficult to judge the target cable through equivalent values. At present, it is rarely used; GPS synchronization method is a new method that has appeared in recent years. , it can realize online cable identification, and the identification rate is high, but its dependence on third-party signals is strong, the receiving and processing time is long, and the operation is not convenient enough. In addition, urban high-rise buildings and trees are blocked, and the signal is unstable. , it is prone to misjudgment. If the online cable identification technology can remove the dependence on the GPS synchronization signal, the practicability and accuracy will be greatly improved.

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