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

Microgrid grounding and interphase fault identification method and system

A phase-to-phase fault and identification method technology, applied in the direction of measuring electricity, measuring electrical variables, instruments, etc., can solve the problems of insufficient sensitivity, low reliability, and slow action speed of the microgrid

Active Publication Date: 2019-12-24
NARI TECH CO LTD +4
View PDF6 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a method and system for identifying micro-grid grounding and phase-to-phase faults, so as to solve the problems of insufficient sensitivity, low reliability, and slow action speed in micro-grid protection caused by the prior art

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
  • Microgrid grounding and interphase fault identification method and system
  • Microgrid grounding and interphase fault identification method and system
  • Microgrid grounding and interphase fault identification method and system

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0050] In order to make the technical means, creative features, goals and effects achieved by the present invention easy to understand, the present invention will be further described below in conjunction with specific embodiments.

[0051] The first aspect: if figure 1 , discloses a method for identifying microgrid grounding and phase-to-phase faults, the method comprising the following steps:

[0052] Step 1: Based on the negative-sequence electrical quantity being the fault characteristic quantity, collect the sampled current value and sampled voltage value of the measured point, and calculate the negative-sequence power frequency mutation value, negative-sequence voltage power-frequency mutation value, and negative-sequence current power frequency mutation value. Mutation value; the specific calculation method is as follows:

[0053]

[0054]

[0055]

[0056] In the above formula is the current sampling time a, b, c phase voltage, are the voltages of phases ...

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 microgrid grounding and interphase fault identification method and system. The microgrid grounding and interphase fault identification method comprises the steps of acquiringa sampling current value and a sampling voltage value of a tested point, and calculating a power frequency break variable value of a negative sequence power, a power frequency break variable value ofa negative sequence voltage and a power frequency break variable value of a negative sequence current; acquiring a real-time load current and a real-time load voltage value of the tested point, and calculating a negative sequence power floating threshold value, a negative sequence voltage floating threshold value and a negative sequence current floating threshold value; and judging a fault pointaccording to a result of comparing the power frequency break variable value of the negative sequence power, the power frequency break variable value of the negative sequence voltage and the power frequency break variable value of the negative sequence current with the negative sequence power floating threshold value, the negative sequence voltage floating threshold value and the negative sequencecurrent floating threshold value in one-to-one correspondence. By the method, the protection action reliability is improved, and the microgrid protection action speed is increased.

Description

technical field [0001] The invention relates to a method and system for identifying grounding and phase-to-phase faults in a microgrid, and belongs to the technical field of electric power system relay protection. Background technique [0002] Due to the short circuit of the microgrid and the characteristics of multiple power sources, variable operation modes, and three-phase asymmetry, it is difficult to set the protection value caused by the protection range of the line and the coordination between adjacent lines with the overcurrent protection of the single-ended criterion. . The micro-power sources in the micro-grid are mostly connected by inverters, and their fault current is limited by semiconductor devices to within 2 times the rated current. Therefore, the fault current at the outlet of the micro-power source will not be as large as that of the traditional grid. When the micro-grid is running off-grid When there is only one micro-power supply, the maximum short-circ...

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): G01R31/02
Inventor 李志坚张海滨郑玉平王伟梅德冬潘书燕刘辉宋鹏侯宇许广婷董璇孙蓉
Owner NARI TECH 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