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

Self-adaptive reclosing method for overhead flexible DC power grid

A reclosing and self-adaptive technology, which is applied in the direction of electrical components, circuit devices, emergency protection circuit devices, etc., can solve the problem that flexible DC power grids require higher breaking capacity of DC circuit breakers, need to be opened again, and overhead flexible DC power grids Secondary hazards and other issues, to achieve the effect of improving safety and power supply reliability, avoiding impact, and reducing breaking capacity

Inactive Publication Date: 2020-02-07
HUAZHONG UNIV OF SCI & TECH
View PDF8 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] Aiming at the defects of the prior art, the object of the present invention is to provide an adaptive reclosing method for the overhead flexible direct grid, which aims to solve the problem that the existing automatic reclosing causes secondary damage to the overhead flexible direct grid and needs to be opened again, thus Leading to the problem that the DC circuit breaker's breaking capacity is relatively high in the flexible DC power grid

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
  • Self-adaptive reclosing method for overhead flexible DC power grid
  • Self-adaptive reclosing method for overhead flexible DC power grid
  • Self-adaptive reclosing method for overhead flexible DC power grid

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0041] In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

[0042] like figure 1 As shown, the present invention provides an adaptive reclosing method for overhead flexible direct grid, including:

[0043] (1) When a DC short-circuit fault signal is received, the DC circuit breaker opens;

[0044] (2) After de-ionizing, reclose some sub-modules of the transfer branch of the DC circuit breaker;

[0045] (3) Part of the overlapped sub-modules are discharged by the capacitor, injecting a voltage traveling wave with a preset amplitude into the fault line, and generating the first singular point of the DC voltage of the line;

[0046] (4) When the voltage tra...

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 self-adaptive reclosing method for an overhead flexible DC power grid, which belongs to the field of flexible DC power transmission. The method comprises the following steps:when a DC short-circuit fault signal is received, a DC circuit breaker is opened; after deionization, part of sub-modules of a transfer branch of the DC circuit breaker are reclosed; the reclosed sub-modules are discharged through a capacitor, a voltage traveling wave with a preset amplitude is injected into a fault line, and a first singular point of the DC voltage of the line is generated; whenthe voltage traveling wave is reflected at the fault point or at the tail end of the fault line, a second singular point of the DC voltage of the line is generated; singular points of the DC voltageare detected by wavelet transformation; and the fault property of the fault line is judged according to the polarities of the wavelet transform mode extreme values of the first singular point and thesecond singular point, and self-adaptive reclosing is carried out. According to the invention, the problem of secondary impact caused by reclosing of the DC circuit breaker in a permanent fault is avoided, and the requirement of the flexible DC power grid for the switching capacity of the DC circuit breaker is reduced.

Description

technical field [0001] The invention belongs to the field of flexible DC power transmission, and more specifically relates to an adaptive reclosing method for an overhead flexible DC power grid. Background technique [0002] With the increasing demand for grid-connected renewable energy, the multi-terminal flexible DC grid based on modular multilevel converter (MMC) technology has become one of the development trends of the future smart grid. [0003] Considering the power transmission distance, voltage level and cost, flexible DC systems often use overhead lines for large-scale power transmission. Most overhead line faults are transient faults. After the fault is isolated, the system should be restarted quickly to restore the power supply of the system, thereby improving the reliability of the system. At present, automatic reclosing schemes are often used in engineering to restart faults. This method cannot judge the nature of the fault. Once it coincides with a permanen...

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): H02H7/26H02H7/28H02H1/00
CPCH02H1/003H02H7/265H02H7/268H02H7/28
Inventor 文劲宇杨赛昭向往
Owner HUAZHONG UNIV OF SCI & TECH
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