Turn-to-turn zero-sequence differential protection method and device for valve side winding of series transformer

A technology for differential protection devices and series transformers, which is applied to emergency protection circuit devices and electrical components, and can solve the problems of unreliable isolation of inter-turn faults in valve side windings of series transformers, insufficient sensitivity of longitudinal differential protection, etc.

Pending Publication Date: 2018-06-22
CHINA ELECTRIC POWER RES INST +1
View PDF0 Cites 21 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] In order to overcome the defect that the inter-turn fault of the valve side winding of the series transformer cannot be reliably isolated due to the insufficient sensitivity of the longitudinal differential protection in the above-mentioned prior art, the present invention provides a zero-sequence differential protection method and device for the valve side winding of the series transformer , first calculate the zero-sequence differential current starting threshold and braking coefficient, then determine the zero-sequence differential current starting criterion according to the zero-sequence differential curren

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
  • Turn-to-turn zero-sequence differential protection method and device for valve side winding of series transformer
  • Turn-to-turn zero-sequence differential protection method and device for valve side winding of series transformer
  • Turn-to-turn zero-sequence differential protection method and device for valve side winding of series transformer

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0052] The present invention will be described in further detail below in conjunction with the accompanying drawings.

[0053] The embodiment of the present invention provides a zero-sequence differential protection method between turns of the valve side winding of a series transformer, in which the series transformer belongs to the main component of the unified power flow controller, and the unified power flow controller is located at the head end of the line. The specific structure diagram is as follows figure 1 As shown, the series transformer is connected in series to the head end of the line PQ, and the parallel transformer is connected to the bus P in parallel. TBS stands for thyristor bypass switch, TBS is connected between the valve side windings of series transformers, and is used to quickly bypass series side converters in emergency conditions. QF 1 and QF 2 Respectively, the switch at the beginning and end of the line PQ, QF 3 and QF 4 are the series transformer...

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 turn-to-turn zero-sequence differential protection method and device for the valve side winding of a series transformer. The turn-to-turn zero-sequence differential protectionmethod comprises the following steps: firstly calculating the starting threshold value and braking coefficient of zero-sequence differential current, then determining zero-sequence differential current starting criterions and valve side winding turn-to-turn zero-sequence differential protection criterions, and finally judging whether valve side winding turn-to-turn zero-sequence differential protection is of actions. In the turn-to-turn zero-sequence differential protection method for the valve side winding of the series transformer provided by the invention, when a small turn-to-turn fault occurs in the valve side winding, under the premise that the protection of a unified power flow controller is free of action, turn-to-turn protection can be accurately and rapidly acted, rapid isolation of the turn-to-turn fault of the valve side winding is guaranteed, the valve side winding is avoided from being damaged, and safe operation of the series transformer is guaranteed.

Description

technical field [0001] The invention relates to the technical field of relay protection, in particular to a method and device for zero-sequence differential protection between turns of a valve side winding of a series transformer. Background technique [0002] As the transmission corridors of the power system become increasingly saturated, it will become more and more difficult to increase the transmission capacity by building new transmission lines. The needs of large-scale interconnected networks to increase the transmission power of the power grid and reduce losses have become urgent problems that need to be solved. Unified Power Flow Controller (UPFC) is a new generation of flexible AC power transmission equipment with the most comprehensive functions so far. The application in actual engineering has obvious technical advantages and broad application prospects. [0003] The series transformer is an important part of UPFC. Its valve-side winding is connected to the conve...

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): H02H7/045
CPCH02H7/045
Inventor 周泽昕柳焕章杜丁香王兴国曹虹
Owner CHINA ELECTRIC POWER RES INST
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