Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

A Calculation Method of Current Transformer Iron Core Saturation Time During Fault

A current transformer and time calculation technology, which is applied in the field of current transformer iron core saturation time calculation during faults, can solve problems such as inability to calculate saturation time, and help accident analysis, improve protection and equipment selection, and overcome estimation The effect of large saturation time error

Active Publication Date: 2019-10-18
POWER DISPATCHING CONTROL CENT OF GUANGDONG POWER GRID CO LTD
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] The present invention overcomes the technical defect that the above-mentioned existing current transformer saturation identification method cannot calculate the saturation time, and provides a current transformer core saturation time calculation method when a fault occurs, which fills in the inability of the existing current transformer saturation identification method Calculation of blanks for saturation time

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 Calculation Method of Current Transformer Iron Core Saturation Time During Fault
  • A Calculation Method of Current Transformer Iron Core Saturation Time During Fault
  • A Calculation Method of Current Transformer Iron Core Saturation Time During Fault

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0046] The accompanying drawings are for illustrative purposes only and cannot be construed as limiting the patent;

[0047] For those skilled in the art, it is understandable that some well-known structures and descriptions thereof may be omitted in the drawings.

[0048] The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0049] The embodiment is the application of the present invention under the short-circuit fault of the AC system.

[0050] S1. Obtain the mathematical expression of the primary short-circuit current by fitting parameters (assuming it is the superposition of the power frequency component and the attenuation non-periodic component), that is Get the primary current power frequency amplitude I psc , primary current time constant T p and the angle θ between the initial short-circuit current and the voltage; a certain short-circuit current waveform is as follows fig...

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 calculation method for saturation time of a current transformer core in a fault. The method comprises the implementation steps that S1, a mathematical expression of a primaryshort-circuit current of a current transformer is obtained through mathematical fitting, and parameters of the current transformer are obtained through measurement of the current transformer; S2, a mathematical expression of saturation magnetic flux of the current transformer is designed through the parameters of the current transformer; S3, a mathematical expression of magnetic flux and the mathematical expression of the saturation magnetic flux are compared, if an intersection exists, the step S4 is executed, and if no intersection exists, the method is ended; and S4, the saturation time ofthe current transformer core is calculated by judging whether residual magnetism exists. Through the method, quantitative calculation can be performed on the saturation time, accuracy is high, and the method is beneficial for accident analysis, protection improvement and equipment model selection; meanwhile, the influence of the residual magnetism on the saturation time is considered, so that themethod has practicability; and moreover, different saturation time is calculated for different types of current transformers, so that the method has universality.

Description

technical field [0001] The invention relates to the technical field of electric power system relay protection, and more particularly, relates to a method for calculating the saturation time of a current transformer iron core during a fault. Background technique [0002] The current transformer is an important device required for the relay protection to judge the operating state of the system, and its measurement accuracy is crucial to the action performance of the relay protection. The complex transient process during abnormal operating conditions such as various forms of short-circuit faults and transformer excitation inrush current will cause the current transformer to be saturated to varying degrees, which will affect the measurement of the secondary current and interfere with the correct judgment of the relay protection. In recent years, there have been many protection misoperation accidents caused by the transient saturation of current transformers on site, which seriou...

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): G06F17/10
Inventor 王育学黄明辉陈志光曾耿晖李一泉刘玮王增超刘琨朱晓华陈桥平
Owner POWER DISPATCHING CONTROL CENT OF GUANGDONG POWER GRID CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com