Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Phase current sudden change based earth fault protection method

A ground fault and sudden change technology, applied in emergency protection circuit devices, electrical components, etc., can solve the problems of line selection troubled by electric workers, weak fault current characteristics, and huge multiplication operations, and achieve high protection accuracy and reliability. performance, computational simplicity, and improved accuracy and reliability

Active Publication Date: 2016-08-31
长沙精科电力技术有限公司
View PDF6 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0002] my country's distribution network widely adopts the non-effective neutral point grounding mode. This mode of operation can effectively improve the reliability of power supply. However, when the single-phase grounding fault occurs, the fault current characteristics are weak, the arc is unstable and other factors, and the line selection problem has always been a problem. Difficulties Plagued by Power Workers
The main difficulties of the wavelet algorithm are: ① easily affected by factors such as wavelet basis functions and decomposition scales; ② a large number of layer-by-layer extraction and separation of sampled data, the amount of multiplication is very huge

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
  • Phase current sudden change based earth fault protection method
  • Phase current sudden change based earth fault protection method
  • Phase current sudden change based earth fault protection method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0021] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0022] Such as figure 1 As shown, the earth fault protection method based on phase current sudden change of the present invention, its steps are:

[0023] S1: Online monitoring of the zero-sequence voltage of the distribution network, when the zero-sequence voltage exceeds the limit (that is, exceeds the voltage limit value), the transient phase current signal of each line is collected;

[0024] S2: Extract the transient phase current mutation amount of each line;

[0025] S3: Perform pairwise correlation analysis on the phase current mutation of each line to obtain the phase-to-phase correlation number [ρ AB ρ BC ρ CA ], the minimum correlation coefficient ρ between phases can be obtained by comparison min ;

[0026] S4: Judging the faulty line according to the size of the correlation coefficient. When the minimum correlatio...

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 discloses a phase current sudden change based earth fault protection method which comprises the following steps: 1) online monitoring the zero sequence voltage of a power distribution network wherein when the zero sequence voltage exceeds the limit value of the voltage, the transient phase current signals of all lines are collected; 2) extracting the sudden changes in the transient phase current signals of all lines; 3) conducting two-on-two correlation analysis on the sudden changes in the transient phase current signals to obtain phase correlation coefficients [Rho AB, Rho BC Rho CA]; comparing for the smallest correlation coefficient Rho min; and 4) based on the identical correlation coefficients to find out the lines in fault. The method, with simple principles, is easy to perform for enhanced protection accuracy and reliability.

Description

technical field [0001] The invention mainly relates to the technical field of distribution network grounding, in particular to a grounding fault protection method based on phase current mutation. Background technique [0002] my country's distribution network widely adopts the non-effective neutral point grounding mode. This mode of operation can effectively improve the reliability of power supply. However, when the single-phase grounding fault occurs, the fault current characteristics are weak, the arc is unstable and other factors, and the line selection problem has always been a problem. Difficulties plaguing electricians. At present, the research on fault line selection has achieved some preliminary results, but the accuracy of line selection in practical applications is still low and needs to be further improved. [0003] The existing ground fault protection methods of distribution network mainly include three methods: injection signal method, steady state method and tr...

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): H02H7/26H02H7/22
CPCH02H7/22H02H7/262H02H7/263
Inventor 曾祥君刘谋海谷应科
Owner 长沙精科电力技术有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com