Dynamic resistance grounding mode of neutral point of power distribution network, and ground fault line selection method

A grounding method and grounding line selection technology, applied in electrical components, emergency protection circuit devices, etc., to achieve the effect of low overvoltage level, small resistive current, and safety risk reduction

Active Publication Date: 2017-03-15
李景禄
View PDF4 Cites 16 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Aiming at the problems existing in the current distribution network neutral point small resistance grounding method, the present invention invents a distribution network neutral point dynamic resistance grounding method and a grounding line selection method. Combined with the co

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
  • Dynamic resistance grounding mode of neutral point of power distribution network, and ground fault line selection method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0014] When the distribution network is in normal operation, the resistance short-circuit switch works in the disconnected state, and the neutral point is grounded through the neutral resistance connected in series, which is used to limit the overvoltage in the distribution network; the neutral point displacement voltage rises to the fault When starting the voltage, immediately, it is judged that a single-phase grounding occurs in the distribution network. First, the ground fault area is judged according to the value of the neutral point displacement voltage. At that time, it is a low-impedance grounding. neutral point and After series connection, the medium resistance is grounded, and the computer measurement and control system compares the zero-sequence current value flowing through each feeder, and uses the zero-sequence current ratio method to select the single-phase grounding fault line; at that time, it is high-impedance grounding, and at this time, the resistance is sho...

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 dynamic grounding mode of a neutral point of a power distribution network in a medium-resistance and low-resistance way, and a ground fault line selection method, for the problem existing in a low-resistance grounding mode of the neutral point of the power distribution network at present. The grounding resistance value of the neutral point of the power distribution network can be dynamically converted according to requirements, namely, when the power distribution network is in a normal operating state, the neutral point is grounded through a resistor and a serially-connected medium resistor for limiting each kind of overvoltage in the power distribution network; when a displacement voltage of the neutral point rises to a fault starting voltage, it is determined that the power distribution network suffers from single-phase grounding immediately; firstly, a grounding fault region is determined according to the displacement voltage value of the neutral point, and at the moment, the low-resistance grounding mode is performed; the neutral point is grounded through the serially-connected medium resistor, a single-phase grounding fault line is selected out by a zero sequence current amplitude-comparing method, and at the moment, a high-resistance grounding mode is performed; and the grounding of the neutral point is converted to low-resistance grounding, and a fault loop current is accelerated to satisfy the detection sensitivity of a zero sequence current transformer so as to select out and cut away the fault line.

Description

technical field [0001] The invention mainly relates to the field of neutral point grounding of a distribution network, in particular to a dynamic resistance grounding mode and a grounding line selection method for a neutral point of a distribution network, and is suitable for single-phase grounding fault processing of a 6-66kv distribution network. Background technique [0002] Different neutral point grounding methods of distribution network have great influence on power supply reliability, internal overvoltage level and lightning arc establishment rate. The neutral point grounding method of the distribution network involves many factors such as the structure of the distribution network, the insulation level of lines and equipment, the configuration of relay protection, the communication system, and personal safety. The neutral point grounding methods of distribution network are: (1) neutral point is insulated from ground; (2) neutral point is grounded through arc suppressi...

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): H02H7/28
CPCH02H7/28
Inventor 李政洋李景禄
Owner 李景禄
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