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

An islanding detection method, device and system based on hybrid power feedback disturbance

An island detection and mixed power technology, which is applied in the direction of measuring devices, electrical devices, and measuring electric power, can solve the problems of large detection blind spots, high misjudgment rates, and low efficiency, and achieve accurate real islands, small detection blind spots, and reduced The effect of small power quality impact

Active Publication Date: 2021-11-30
STATE GRID HUNAN ELECTRIC POWER
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to provide an islanding detection method, device and system based on hybrid power feedback disturbance to inject active voltage feedback disturbance and reactive frequency feedback into the grid-connected inverter at the same time. Island detection by disturbance, which solves the technical problems of large detection blind area, low reliability and low efficiency and high misjudgment rate caused by single power feedback disturbance in the existing island detection

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
  • An islanding detection method, device and system based on hybrid power feedback disturbance
  • An islanding detection method, device and system based on hybrid power feedback disturbance
  • An islanding detection method, device and system based on hybrid power feedback disturbance

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0045] Embodiment one, as figure 1 As shown, an islanding detection method based on hybrid power feedback disturbance, including the following steps:

[0046] S1: Obtain the local load consumption power and grid transmission power of the micro-grid in real time, and judge whether the operating state of the micro-grid falls into the limit of the overvoltage and underfrequency detection method according to the local load consumption power and the grid transmission power Detect blind areas, if yes, perform S2, if not, use the over-undervoltage and over-underfrequency detection method to perform islanding detection on the microgrid, and obtain an islanding detection result;

[0047] S2: Determine the dominant feedback disturbance of the microgrid according to the local load consumption power and the grid transmission power; wherein, the dominant feedback disturbance is an active voltage feedback disturbance or a reactive frequency feedback disturbance;

[0048] S3: Obtain the dis...

Embodiment 2

[0132] Embodiment two, such as Figure 12 As shown, an island detection device based on hybrid power feedback disturbance includes a power acquisition module, a detection blind zone discrimination module, an island routine detection module, a feedback disturbance analysis module, a feedback coefficient calculation module, a disturbance injection module, an island initial detection module and an island Check the module again;

[0133] The power collection module is used to obtain the local load consumption power, grid transmission power and distributed power output power of the microgrid in real time;

[0134] The detection blind zone discrimination module is used to judge whether the operation state of the microgrid falls into the detection blind zone of the overvoltage and undervoltage and underfrequency detection method according to the local load consumption power and the grid transmission power;

[0135] The island conventional detection module is used to use the over-und...

Embodiment 3

[0142] Embodiment 3. An islanding detection system based on hybrid power feedback disturbances, including the islanding detection device based on hybrid power feedback disturbances in Embodiment 2, and also includes distributed power sources, grid-connected inverters, local loads and grid-connected breaker;

[0143] The distributed power supply is electrically connected to the local load and the grid-connected circuit breaker through the grid-connected inverter, and the grid-connected circuit breaker is also electrically connected to the microgrid. The distributed power supply, the The grid-connected inverter, the local load and the grid-connected circuit breaker are all electrically connected to the islanding detection device based on hybrid power feedback disturbance.

[0144] On the one hand, it reduces the impact of power feedback disturbance on power quality, and on the other hand, it improves the detection speed. The hybrid power feedback disturbance based on multi-decis...

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 present invention relates to an islanding detection method, device and system based on hybrid power feedback disturbance, including real-time acquisition of local load consumption power, power grid transmission power and distributed power output power, and judging whether the operating state of the microgrid falls into overvoltage and undervoltage and The detection blind area of ​​the over-under-frequency detection method, if not, use the over-under-voltage and over-under-frequency detection method to perform island detection on the microgrid; if so, determine the dominant feedback disturbance and calculate the active voltage feedback coefficient and reactive frequency feedback coefficient; Simultaneously inject active voltage feedback disturbance and reactive frequency feedback disturbance into the microgrid; first judge whether islanding occurs according to the grid-connected point voltage within the first preset time or the grid-connected point frequency within the second preset time, and if so, calculate the grid equivalent Resistance and judge whether real islanding occurs again according to the grid equivalent resistance. The invention is based on the mixed power feedback disturbance, has a small detection blind area, and realizes higher reliability, accuracy and adaptability.

Description

technical field [0001] The invention relates to the field of flexible microgrid protection and control, in particular to an islanding detection method, device and system based on hybrid power feedback disturbance. Background technique [0002] The use of various distributed power generation and energy storage devices in the microgrid not only achieves energy saving and emission reduction, but also greatly promotes my country's sustainable development strategy. When the power supply of the microgrid is interrupted due to faults, man-made or natural reasons, the photovoltaic system fails to detect the power outage in time and disconnects from the grid, making the system and surrounding loads form an uncontrolled self-powered island. The existence of the island effect causes many hazards, such as: the power supply voltage and frequency in the island area are unstable; it affects the related protection operations of the power distribution system; the single-phase power supply of...

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): G01R31/00G01R21/00G01R19/165
CPCG01R19/16547G01R21/00G01R31/00
Inventor 徐宇新黄勇王阳光张孝军
Owner STATE GRID HUNAN ELECTRIC POWER
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