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

A frequency band adaptive acquisition method for single-phase ground fault line selection in distribution network

A single-phase-to-ground fault and acquisition method technology, applied in the fault location and other directions, can solve the problems of inaccurate frequency band selection, invalid criterion, insufficient sensitivity, etc., and achieve the effect of solving inaccurate frequency band selection.

Active Publication Date: 2018-02-06
XIAN XIRUI ELECTRIC ENG CO LTD
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to propose an adaptive acquisition method for the line selection frequency band of a single-phase ground fault in a small current grounding system that is not affected by the operation mode and inaccurate line parameters, so as to solve the problem caused by the inaccurate frequency band selection of the traditional line selection method. Insufficient sensitivity and criterion failure of

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
  • A frequency band adaptive acquisition method for single-phase ground fault line selection in distribution network
  • A frequency band adaptive acquisition method for single-phase ground fault line selection in distribution network
  • A frequency band adaptive acquisition method for single-phase ground fault line selection in distribution network

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0017] figure 1 Middle R 0k , L 0k 、C 0k , C' 0k represent the equivalent parameters of the line π model respectively, where C 0 ' k ≠C 0k , indicating the influence of load-side branch capacitance, etc. 3L is the inductance of the arc suppressing coil. When the switch is opened, the system is not grounded, and when the switch is closed, the system is grounded through the arc suppressing coil. i 0i (i=1,2...,n) represents the zero-sequence current of n outgoing lines, which is capacitive. i L Indicates the current in the arc suppressing coil, which is inductive.

[0018] According to the characteristics of single-phase grounding faults, the equivalent network of single-phase grounding in small current grounding systems is established by using Karen Bauer phase-mode transformation, such as figure 2 shown.

[0019] where u f is the additional power supply at the point of failure, R f is the transition resistance, u 1f , u 2f , u 0f is the network port voltage o...

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 frequency band self-adaptive acquisition method for single-phase grounding line selection of a distribution network. When a single-phase ground fault occurs in the distribution network, the zero-sequence current of each outgoing line can be divided into a common mandatory component under the action of zero-sequence voltage and a free component generated by the charging and discharging of inductive and capacitive elements related to the parameters of the line itself. The common frequency and corresponding phase of the zero-sequence current of each outgoing line are solved by using the matrix beam algorithm. Sort the common frequencies from small to large and perform a phase group ratio to find the frequency so that the phase of each common frequency component of a certain outgoing line is always opposite to that of other lines or the common frequency components of all outgoing lines are always in the same phase until the next frequency No longer satisfied, this frequency is the upper band limit. The lower limit of the frequency band of the arc-suppression coil grounding system is 150Hz, and the lower limit of the frequency band of other indirect grounding systems is 0. This method is not affected by the operation mode of the distribution network and the imprecise line parameters.

Description

technical field [0001] The invention relates to a new method for relay protection of an electric power system, in particular to a method for adaptively acquiring frequency bands for line selection for single-phase grounding faults in a distribution network based on a matrix bundle algorithm. Background technique [0002] The problem of line selection for single-phase ground faults in low-current grounding systems has always been a hot and difficult research point, and the current mainstream is the line selection method based on transient information. These transient methods are mainly divided into two categories: 1) Line selection methods based on the amplitude and phase relationship between the transient zero-sequence voltage and each outgoing zero-sequence current in the characteristic frequency band; 2) Selection methods based on other transient characteristics line method. When a single-phase ground fault occurs in a low-current grounding system, the most basic fault fe...

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 Patents(China)
IPC IPC(8): G01R31/08
Inventor 宋国兵常仲学张恒泰
Owner XIAN XIRUI ELECTRIC ENG CO LTD
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