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

A Fault Line Selection Method of Distribution Network Based on Zero Sequence Current Differential Polarity Comparison

A technology for distribution network faults and zero-sequence currents, applied in fault locations, detecting faults according to conductor types, and measuring electricity, etc., can solve problems such as hidden dangers of distribution network safety, and achieve low sampling frequency, easy implementation, and high accuracy. Effect

Active Publication Date: 2019-04-09
KUNMING UNIV OF SCI & TECH
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, such a long-term operation will bring huge hidden dangers to the distribution network, so it is necessary to optimize and study the method of fault line selection in the distribution network

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 Fault Line Selection Method of Distribution Network Based on Zero Sequence Current Differential Polarity Comparison
  • A Fault Line Selection Method of Distribution Network Based on Zero Sequence Current Differential Polarity Comparison
  • A Fault Line Selection Method of Distribution Network Based on Zero Sequence Current Differential Polarity Comparison

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0021] Embodiment 1: A distribution network fault line selection method based on zero-sequence current differential polarity comparison. A simulation model is built according to the parameters of the distribution network operation. By setting different lines and phase-to-phase ground faults in the simulation model, Obtain the line power frequency zero-sequence current signal i generated by each simulated line under the ground fault 0i (t); Select the zero-sequence current i within 10ms after the fault 0i (t); then define the zero-sequence current differential function F of the line i (t), find the zero-sequence current i 0i (t) difference function F i (t), and then use the difference function F i (t) Construct P i (t), using P i (t) Compare the zero-sequence current polarity of each line, when P i (t)=max{P 1 (t),P 2 (t)...,P n (t)}, then line i is a faulty line; when P i (t)≠max{P 1 (t),P 2 (t)...,P n (t)}, then i is a non-faulty line.

[0022] The specific step...

Embodiment 2

[0035] Embodiment 2: The other parts of this embodiment are the same as Embodiment 1, as shown in Figure 1, the simulation model of 110kV / 35kV distribution network is shown in Figure 1, it has 6 feeders, and the neutral point of the Z-shaped transformer passes through The arc coil series resistor is grounded. Overhead feeder L 1 =18km,L 3 =30km, cable feeder L 2 =7km. G in the power grid is an infinite power source; T is the main transformer, the transformation ratio is 110kV / 35kV, and the connection group is Y N / d11;T Z Is a zigzag transformer; L is the arc suppression coil; R is the damping resistance of the arc suppression coil. The feeder adopts three types of lines: overhead line, overhead line-cable hybrid line and cable line. The load uses a constant power load model.

[0036] (1) Feeder L 2 A single-phase grounding fault occurs in phase B 10 kilometers away from the beginning, the grounding resistance is 10Ω, the fault angle is 60°, and the sampling frequency ...

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 relates to a zero sequence current difference polarity comparison based power distribution network fault line selection method, which belongs to the technical field of electric power system fault line selection. According to the parameters for the operation of a power distribution network, a simulation model is set up. By setting different lines to have grounding faults with the phases respectively in the simulation model, power line work frequency zero-sequence current signals are generated among the simulated lines. The zero-sequence current within 10ms is selected after the faults occur. Then, the zero-sequence current differential function is defined and calculated; after that, the differential function is used to construct fault discriminators; based on the fault discriminators, the polarity of the zero sequence current of each line is compared. When the value of the fault discriminator of a certain line is equal to the maximum value of all the line fault discriminators, the line is determined as a faulty line. When the value of the fault discriminator of the certain line is not equal to the maximum value of all the line fault discriminators, the line is determined as a non-faulty line.

Description

technical field [0001] The invention relates to a fault line selection method of a distribution network based on zero-sequence current differential polarity comparison, and belongs to the technical field of power system fault line selection. Background technique [0002] The distribution network is the most direct link with users in the power system, and its coverage is extensive. Compared with the transmission network, the fault probability is higher, and single-phase grounding is the main fault type that occurs in the distribution network operation. When a single-phase ground fault occurs in the distribution network whose neutral point is grounded through the arc suppression coil, the three-phase line voltage of the power grid always maintains symmetry. Due to the compensation effect of the arc suppression coil, the fault current generated is small. According to the power system Operating procedures In this case, the system can continue to run for 1-2 hours with a fault, w...

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): G01R31/08
CPCG01R31/086G01R31/088
Inventor 王书领李文泽马聪
Owner KUNMING 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