Method for recognizing magnetizing rush current of transformer based on dynamic quadrangle shape analysis

A technology of excitation inrush current and identification method, which is applied in the direction of external dimension measurement, electrical components, emergency protection circuit devices, etc., can solve problems such as misjudgment and inaccurate judgment results, and achieve the effect of avoiding inaccuracy, easy implementation, and simple principle

Active Publication Date: 2015-05-06
XIAN UNIV OF TECH
View PDF1 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a transformer excitation inrush identification method based on dynamic quadrilateral shape analysis, which solves the problem that the local waveform distortion in the existing technology of identifying excitation inrush current based on waveform characteristics will lead to inaccurate or even misjudged results.

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
  • Method for recognizing magnetizing rush current of transformer based on dynamic quadrangle shape analysis
  • Method for recognizing magnetizing rush current of transformer based on dynamic quadrangle shape analysis
  • Method for recognizing magnetizing rush current of transformer based on dynamic quadrangle shape analysis

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0044] by image 3 (a) Transformer excitation inrush current and image 3 The fault current waveform inside the transformer shown in (b) is taken as an example for testing.

[0045] Step 1. Collect and analyze the 3 / 2 cycle A-phase current waveform from the moment the circuit breaker closes, and filter the current waveform to filter out serious waveform distortion points.

[0046] Step 2. Sampling the current waveform collected in step 1 to obtain the value of each sampling point.

[0047] Step 3. Determine the maximum value point X, the minimum value point Y and the line segment MN among the sampling points, count the number n of sampling points between MN, and determine that point O is the kth sampling point. right image 3 Inrush current shown in (a), n=204, k=81; image 3 The internal fault current shown in (b), n=202, k=100.

[0048] Step 4. Move the sampling point from point O to obtain the quadrilateral ABCD, and calculate the angle θ between the line segment DA an...

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 discloses a method for recognizing magnetizing rush current of a transformer based on dynamic quadrangle shape analysis. The method specifically comprises the steps of acquiring differential current waveforms of current mutual inductors at two differential protection sides of the transformer, and sampling; dividing the current waveforms into two parts according to the equal area condition; gradually moving the sampling points in the two waveform parts and forming a quadrangle set; determining the shape of each quadrangle; counting the proportion of parallelogram in the quadrangle set; determining whether the type of the current waveform is the type of magnetizing rush current or internal fault current according to the proportion. With the adoption of the method for recognizing magnetizing rush current of the transformer based on dynamic quadrangle shape analysis, the magnetizing rush current of the transformer can be effectively and reliably recognized, and thus the influence of local deformation of the sampled waveforms on the determining result can be effectively avoided.

Description

technical field [0001] The invention belongs to the technical field of transformer relay protection, and in particular relates to a transformer excitation inrush current identification method based on dynamic quadrilateral shape analysis. Background technique [0002] The transformer is one of the important equipment in the power system, which plays an important role in voltage change and power transmission. The safe and reliable operation of the transformer is directly related to the safety and stability of the power system. At the same time, the transformer is expensive, and the maintenance time is long and difficult. Once it is damaged due to a fault, it will cause major economic losses. Therefore, it has important theoretical significance and engineering value to ensure that the protection scheme of the transformer is accurate and reliable. [0003] Differential protection with better sensitivity and selectivity is generally used as the main protection in the protection...

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): H02H7/045G01R29/04
Inventor 段建东闫富平李笑张宏光慕腾
Owner XIAN UNIV OF 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