Method for detecting and identifying constructional deficiencies of high-voltage and supervoltage cables and cable sets

A cable accessory and defect detection technology, applied in the direction of measuring electricity, measuring devices, measuring electrical variables, etc., can solve problems such as the defect type that cannot be given discharge, the uncertainty of cable line maintenance decision-making, etc., and achieve the effect of real-time monitoring

Inactive Publication Date: 2010-02-17
WUHAN NARI LIABILITY OF STATE GRID ELECTRIC POWER RES INST
View PDF0 Cites 32 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The existing XLPE partial discharge on-line detection device can detect partial discharge, but it cannot give the type of defect that caused the discharge, which brings uncertainty to the decision-making of cable line maintenance

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for detecting and identifying constructional deficiencies of high-voltage and supervoltage cables and cable sets
  • Method for detecting and identifying constructional deficiencies of high-voltage and supervoltage cables and cable sets
  • Method for detecting and identifying constructional deficiencies of high-voltage and supervoltage cables and cable sets

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0041] Embodiment: Extract the partial discharge signal from a certain 110kV cable intermediate joint, and the discharge spectrum formed is as follows image 3 , Figure 4 shown.

[0042] Calculate its discharge spectrum statistics operator:

[0043] (1) Skewness: Sk+=0.134, Sk-=-0.028;

[0044] (2) Steepness: Ku+=-1.129, Ku-=-1.405;

[0045] (3) Number of peaks: Pe+=98, Pe-=101;

[0046] (4) Degree of asymmetry: Asy=0.621;

[0047] (5) Modified cross-correlation coefficient: mcc=0.485;

[0048] (6) Phase coefficient: ph=0.188.

[0049] Then calculate and form the partial discharge grayscale image and Weibull statistical parameters in sequence.

[0050]By comparing the above parameters with the typical defects in the sample library, it is judged that the partial discharge defect type of the cable joint is low-voltage floating discharge, which is consistent with the actual discharge defect of the cable joint.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a method for detecting and identifying constructional deficiencies of high-voltage and supervoltage cables and cable sets, which belongs to the field of power cable detection. Ameasurement unit conditions and acquires signals of a sensor and the signals are transmitted to an industry control computer by a USB communication mode. Software extracts various characteristic quantities of a discharge spectrum from local discharge signals and compares with a local discharge spectrum caused by the constructional deficiency of a prepared typical joint so as to judge whether an on-site running cable joint has deficiencies or not and judge the type of the deficiencies. The invention has the advantages that the method can carry out local discharge detection on electrified cablemiddle joints and effectively monitor insulated conditions according to the on-site requirement, thereby realizing the detection and the identification on the constructional deficiencies of the joints, providing scientific basis for the state maintenance of a cable system and improving the power supply reliability of the cable system.

Description

technical field [0001] The invention relates to a method for detecting and identifying construction defects of high-voltage and ultra-high-voltage cable accessories, which belongs to the field of power cable detection. Background technique [0002] In high-voltage and ultra-high-voltage cross-linked polyethylene (XLPE) power cable systems, cable accessories such as intermediate joints are manually manufactured and installed under on-site conditions, and their insulation quality is often lower than that of the cable body, which is the weak link in the cable system. . Various construction defects caused by poor construction technology of the intermediate joint make the electric field distribution in the joint uneven, resulting in partial discharge. Under power frequency voltage, partial discharge will cause the generation and expansion of electric tree in the cable insulation, and accelerate the deterioration of insulation, eventually leading to insulation breakdown. [0003...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01R31/08G01R31/12G01R31/02
Inventor 罗俊华赵健康李文杰夏荣蒙绍新
Owner WUHAN NARI LIABILITY OF STATE GRID ELECTRIC POWER RES INST
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap