Distinguishing method of inrush current blocking of transformer

A discrimination method and transformer technology, applied in the direction of instruments, measuring electrical variables, measuring devices, etc., can solve the problems of symmetric inrush differential protection, which is prone to misoperation, etc., and achieve the effect of reliable locking, ensuring operation speed, and preventing misoperation

Inactive Publication Date: 2013-10-02
STATE GRID CORP OF CHINA +2
View PDF9 Cites 23 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a discrimination method for transformer inrush current blocking, which is used to solv

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
  • Distinguishing method of inrush current blocking of transformer
  • Distinguishing method of inrush current blocking of transformer
  • Distinguishing method of inrush current blocking of transformer

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0030] The present invention will be described in further detail below in conjunction with the accompanying drawings.

[0031] Such as figure 1 Shown is the flow chart of the discrimination method for transformer excitation inrush current blocking proposed by the present invention. Specific steps are as follows:

[0032] 1. Sampling the phase current of each side of the transformer;

[0033] 2. Judging whether the no-load closing conditions of the transformer are satisfied according to the collected phase current of each side:

[0034] figure 2 It is a block diagram of transformer no-load closing logic, and the specific judgment logic is as follows:

[0035] 1) Before the transformer is put into the system, the phase current on each side of the transformer is less than the preset no-current threshold, and this state lasts for a preset time setting of 1;

[0036] 2) When the transformer is put into the system, the phase current of at least one side of the transformer is 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 distinguishing method of the inrush current blocking of a transformer, which comprises the following steps: 1) judging whether the transformer is in no-load closing; 2) when the transformer is in load closing, adopting a conventional method to judge whether the protection blocking is started or not, when the transformer is in no-load closing, adopting a wave form factor method to judge the failure or the inrush current, if the judging result is inrush current, starting the protection blocking, and if the judging result is failure, opening the protection blocking. The method can judge the symmetrical inrush current better, and solves the problem that the differential protection to the symmetrical inrush current is easy to malfunction when the transformer air-drops.

Description

technical field [0001] The invention relates to a method for judging transformer inrush current blocking. Background technique [0002] The transformer is an essential and important equipment in the power system. In order to prevent serious damage to the transformer when an internal fault occurs, usually a large-capacity transformer must be equipped with a current differential protection as the main protection; the basic principle of the current differential protection is Kirkho husband's law. When the transformer performs no-load closing and external fault recovery, it is usually accompanied by the generation of excitation inrush current, which may easily cause the malfunction of current differential protection. At present, the principle of second harmonic blocking is mostly used. [0003] In the HVDC power transmission system, the converter station no longer has typical industrial frequency power characteristics due to its nonlinear characteristics; the filter on the AC ...

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): G01R31/00
Inventor 张红跃张振华熊章学宋红涛柳明路振宇徐玉洁牛志雷
Owner STATE GRID CORP OF CHINA
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