Electric cable running state diagnosis method and system

Abstract

The invention discloses a cable operation state diagnosis system. The system realizes cable operation state diagnosis by measuring and analyzing cable broadband impedance spectrum data, and specifically includes three major functions: (1) cable overall operation state evaluation; (2) cable local Locating and diagnosing latent defects; (3) Rapidly locating permanent cable faults. The main components of the system are as follows: firstly, the cable initial characteristic parameter management module realizes the calculation of the initial characteristic parameters of the cable by inputting the cable geometric dimension data and the cable insulating material dielectric function data; then the cable broadband impedance spectrum measurement module automatically selects the appropriate frequency according to the cable length range, measure the broadband impedance spectrum of the head end of the cable under test; finally, the cable broadband impedance spectrum positioning analysis module analyzes and processes the initial characteristic parameters of the cable and the measured impedance spectrum data, so as to realize the evaluation of the overall aging state of the cable, the diagnosis of local latent defects of the cable and Cable permanent fault fast location function. The invention fills the gap of using the cable broadband impedance spectrum data to diagnose the running state of the cable at present, and has the characteristics of convenient use, high accuracy and no damage to the cable.

Description

technical field [0001] The invention belongs to the technical field of cable diagnosis, and more specifically relates to a method and system for diagnosing the running state of a cable. Background technique [0002] Cables play an extremely important role in the transmission of electric energy and communication signals in modern large-scale electrical systems. Cables in operation are prone to permanent faults. Once a cable fault occurs, it will cause a large electrical system to shut down or even go out of control, causing serious economic losses and social impact. [0003] The power cables in the urban power supply system are laid in cable trenches or directly buried underground. The laying environment and usage status will greatly affect the life of the cables. Power cables operate under different soil, moisture, moisture, and temperature environments for a long time, and the insulation is susceptible to corrosion and penetration, resulting in partial insulation aging; un...

AI Technical Summary

Problems solved by technology

[0005] There are a large number of cables with short length and high voltage level in nuclear power plants. The occurrence of nuclear power accidents often begins with local nuclear leakage. Under high-dose nuclear radiation, the organic polymer structure of cables will be destroyed and rapid aging will occur, which will lead to cable The failure makes the reactor out of control, which will eventually lead to a major safety accident in the nuclear power plant

[0006] It can be seen that it is of great significance to realize the diagnosis of cable operation status. The diagnosis of cable operation status includes the evaluation of the overall operation status of the cable, the location of local latent defects of the cable, and the rapid location of the cable after a permanent fault. The existing instruments cannot realize the above functions at the same time. , especially for the location of latent defects in cables, there is still a lack of very reliable diagnostic instruments

Images