Failure line selection method of small current ground system by using simulation after zero mode current measure

A low-current grounding, zero-mode current technology, applied in electrical components, emergency protection circuit devices, etc., can solve problems such as ignoring fault characteristics and thorough analysis

Inactive Publication Date: 2008-08-13
KUNMING UNIV OF SCI & TECH
View PDF0 Cites 54 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, if you rely too much on mathematical analysis tools and ignore the thorough analysis of the fault characteristics themselves, the solution to the problem will undoubtedly be at a loss

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
  • Failure line selection method of small current ground system by using simulation after zero mode current measure
  • Failure line selection method of small current ground system by using simulation after zero mode current measure
  • Failure line selection method of small current ground system by using simulation after zero mode current measure

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0094] When a single-phase ground fault occurs in a low-current grounding system, the above principles can be used to achieve perfect fault line selection. The specific implementation process is shown in Figure 7.

[0095] Concrete implementation steps of the present invention are as follows:

[0096] 1. When the bus zero-mode voltage instantaneous value u n (t) greater than K u u n , the fault line selection device starts immediately, and records the zero-mode current of each feeder for one fault cycle, where K u The general value is 0.15, U n Indicates the rated voltage of the busbar;

[0097] 2. Design a zero-phase-shift digital filter to filter out the attenuated DC component and steady-state power frequency component in the zero-mode current, obtain the high-frequency transient component of the zero-mode current, and only consider the path of the high-frequency transient component, as shown in Figure 2 The middle switch K can be regarded as disconnected;

[0098] 3...

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 fault route-selecting method by using small current grounding system simulated by measured zero-mode current. The method includes following steps: when a generatrix zero-mode voltage instantaneous value is over the limit, a fault route-selecting is started and recorded immediately; zero-phase shift digital wave filter is used to obtain a high-frequency transient weight of each feed line zero-mode current; orderly the feed line is supposed to be fault feed line, the rest of the high-frequency transient weight of the feed line zero-mode current is quantificationally solved by using the measured simulative method according to the supposed high-frequency transient weight of the feed line zero-mode current and each feed line zero-order distributing capacitance parameter; the actual-measured wave shape and simulative wave shape of the high-frequency transient weight of the feed line zero-mode current are analyzed and a average relative coefficient of the actual-measured wave shape and simulative wave shape of the high-frequency transient weight of the feed line zero-mode current are solved, the route-selecting criterion is formed to achieve the fault route selection. The principle analysis and simulation indicate that route selection of this method is accurate and reliable.

Description

technical field [0001] The invention relates to the technical field of electric power system relay protection, in particular to a fault line selection method for a small current grounding system simulated after zero-mode current measurement. Background technique [0002] my country's 6-66kV distribution network adopts non-effective grounding methods such as ungrounded neutral point and resonance grounding. Due to the difficulty in line selection for single-phase ground faults in small current grounding systems (also known as small grounding current systems), and people's lack of attention to the application of distribution network protection, there is insufficient trust in the single-phase ground fault line selection technology of small current grounding systems. Many power supply enterprises still use the method of manual routing to realize fault line selection, which seriously restricts the development of distribution automation. Reliable line selection methods and techni...

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): H02H7/26
Inventor 束洪春彭仕欣李斌董俊刘志坚孙士云刘可真唐岚邱革非
Owner KUNMING UNIV OF SCI & TECH
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