A single-phase ground fault detection method and detection equipment for transmission and distribution lines

A single-phase ground fault, transmission and distribution line technology, applied in the direction of measuring electricity, measuring devices, measuring electrical variables, etc., can solve the problem of inability to accurately detect the magnitude of transients, overlapping frequency ranges of transient currents, and inability to reliably detect single-phase Ground faults, etc.

Inactive Publication Date: 2011-12-21
DEXINDONGYUAN INTELLIGENT TECH BEIJING CO LTD
View PDF5 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although the transient current is relatively obvious, because the duration of the transient is very short and it is a fast decay process, less than a quarter of the power frequency cycle, the detection equipment obviously cannot accurately detect the instantaneous value of the transient, so It is also impossible to accurately detect the magnitude of the transient quantity

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 single-phase ground fault detection method and detection equipment for transmission and distribution lines
  • A single-phase ground fault detection method and detection equipment for transmission and distribution lines
  • A single-phase ground fault detection method and detection equipment for transmission and distribution lines

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0027] When a single-phase ground fault occurs in a neutral point ungrounded system, one of the basic characteristics of the line is that the transient current jumps instantaneously and the ground phase voltage drops. Since the sudden change characteristic of the transient current is relatively obvious, the present invention utilizes this characteristic to reliably detect the occurrence of a single-phase grounding fault.

[0028] The present invention provides a detection method for a single-phase ground fault:

[0029] (1) Detection of sudden change rate of line transient current, ΔI p / Δt>R h ;

[0030] (2) Detection line voltage drop, Vh .

[0031] Among them, ΔI p is the sudden change value of transient current, Δt is the time constant of transient quantity jump, R h is the preset threshold for judging the effectiveness of the transient current mutation rate, V h is the preset threshold for judging voltage drop.

[0032] Among them, the transient circuit mutation va...

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 and equipment for detecting a single-phase earth fault of a transmission and distribution line. The method comprises the following steps of: 1, detecting the mutation rate of transient current of the line, wherein the mutation rate Delta Ip/Delta t of the transient current is greater than Rh when the transient current positively jumps; and 2, determining a short-circuit earth fault when detecting that line voltage drops and V is smaller than Vh, wherein the sequence of the step 1 and the step 2 can be changed. According to the fault detection equipment, false alarm or alarm omission can be prevented, demands of different users can be met, and the equipment is applicable for mass production.

Description

technical field [0001] The invention relates to power equipment, in particular to the detection of single-phase grounding faults of power transmission and distribution lines. Background technique [0002] Transmission and distribution lines have many branches, long lines, and complex loads. However, when a ground fault occurs, these faults must be eliminated as soon as possible, otherwise the phase voltage will increase, which will seriously damage the insulation performance of the power supply equipment and lines, and then cause phase-to-phase short-circuit faults, thereby reducing the quality and efficiency of power supply. To troubleshoot, you must first find the location where the fault occurred. [0003] For neutral point non-directly grounded power transmission and distribution systems, when a single-phase ground fault occurs, the line voltage does not change, the line load current does not change, and the characteristic quantity is not very obvious, so single-phase g...

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
IPC IPC(8): G01R31/02G01R19/12
Inventor 何晋章
Owner DEXINDONGYUAN INTELLIGENT TECH BEIJING CO LTD
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