A Phantom Grounding Identification Method of Distribution Network Based on the Distance Between Adjacent Points on the Plane Constructed by Zero-sequence Voltage Adjacent Sub-differences

A technology of zero-sequence voltage and phantom grounding, which is applied in the direction of measuring electricity, measuring electrical variables, measuring devices, etc., can solve the problems of long time window, unfavorable discovery, etc., and achieve the effect of easy realization and simple calculation

Active Publication Date: 2016-07-20
KUNMING UNIV OF SCI & TECH
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is to provide a method for distinguishing phantom grounding and single-phase grounding faults based on the distance between adjacent points on the plane formed by the adjacent sub-difference of zero-sequence voltage, which overcomes the existing methods for identifying phantom grounding and single-phase grounding The required time window is long, which is not conducive to timely detection of single-phase ground faults

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 Phantom Grounding Identification Method of Distribution Network Based on the Distance Between Adjacent Points on the Plane Constructed by Zero-sequence Voltage Adjacent Sub-differences
  • A Phantom Grounding Identification Method of Distribution Network Based on the Distance Between Adjacent Points on the Plane Constructed by Zero-sequence Voltage Adjacent Sub-differences
  • A Phantom Grounding Identification Method of Distribution Network Based on the Distance Between Adjacent Points on the Plane Constructed by Zero-sequence Voltage Adjacent Sub-differences

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0043] Embodiment 1: A distribution network phantom grounding identification method based on the distance between adjacent points on the plane formed by the adjacent sub-differences of the zero-sequence voltage. Calculate the first-order difference and second-order difference of the zero-sequence voltage data of the distribution network bus in the short time window after the phantom grounding, use the first-order difference and second-order difference to construct a plane, and calculate the adjacent points on the plane The sum of squares of the distances is used to distinguish phantom grounding and single-phase grounding faults according to the sum of squares of distances between adjacent points.

[0044] The specific steps of the method are as follows:

[0045] (1) After a single-phase ground fault or phantom ground occurs in the distribution network line, the line selection device starts immediately and records the wave, and records the zero-sequence voltage of the bus;

[...

Embodiment 2

[0058] Embodiment 2: as figure 1 The shown 110kV / 35kV neutral point is grounded through the arc suppressing coil single-phase ground fault simulation model of the distribution network system. It has 6 feeders, and the neutral point of the Z-shaped transformer is grounded through the arc suppressing coil in series with resistance. Overhead feeder L 1 =15km,L 3 =18km, L 5 = 30km, wire-cable hybrid feeder L 4 =17km, the overhead feeder is 12km, the cable is 5km, and the cable feeder is L 2 = 6km, L 6 = 8km. Among them, the overhead feeder is JS1 rod type, LGJ-70 type conductor, the span is 80m, and the cable feeder is YJV23-35 / 95 type cable. G in the power grid is an infinite power source; T is the main transformer, the transformation ratio is 110kV / 35kV, and the connection group is Y N / d11;T Z Is a zigzag transformer; L is the arc suppression coil; R is the damping resistance of the arc suppression coil. The feeder adopts three types of lines: overhead line, overhead l...

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 relates to a power distribution network virtual grounding identification method based on planar adjacent point distances formed by zero sequence voltage adjacent difference and belongs to the technical field of power system relay protection. The method includes: when a fault or virtual grounding occurs on a power distribution network with a neutral point grounded through an arc suppression coil, extracting the distribution network bus zero sequence voltage data in a short time window after the fault or the virtual grounding; calculating the first difference and the second difference of the zero sequence voltage data, building a plane with the first difference and the second difference, calculating the quadratic sum of the adjacent point distance on the plane, and judging the virtual grounding and single-phase grounding fault according to the quadratic sum. The method has the advantages that only differentiation, square and summation need to be performed on the zero sequence voltage data, and the method is simple in calculation and easy to implement.

Description

technical field [0001] The invention relates to a virtual grounding identification method of a distribution network based on the distance between adjacent points on a plane formed by adjacent sub-differences of zero-sequence voltage, and belongs to the technical field of electric power system relay protection. Background technique [0002] When the distribution network whose neutral point is grounded through the arc-suppression coil is in normal operation, the arc-suppression coil is usually in an overcompensated state. When the system feeder increases, the capacitive current of the system increases, and the automatic tuning device will automatically track the change of the capacitive current to adjust the inductance value of the arc suppression coil. During the adjustment process, the system is likely to enter a full compensation state, resulting in parallel resonance overvoltage, resonance The overvoltage may approach or even exceed the neutral point displacement voltage f...

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): G01R31/00
Inventor 束洪春曹璞璘高利方夏
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