Method for calculating zero sequence mutual inductive impedance in multiple transmission lines on common tower

A zero-sequence mutual inductance and transmission line technology, applied in the field of zero-sequence mutual inductance impedance calculation, can solve problems such as inconsistency, error, and rationality to be explored, and achieve the effect of simple operation process, high accuracy, and strong achievability

Active Publication Date: 2017-10-20
GUANGZHOU POWER SUPPLY BUREAU GUANGDONG POWER GRID CO LTD
View PDF4 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] When the empirical method is used to estimate the zero-sequence mutual inductance impedance, the influence of soil resistivity and tower structure is not considered, which is seriously inconsistent with the actual situation
When using the empirical estimated value of zero-sequence mutual inductance impedance for fault calculation and simulation analysis, the results may have large errors with the real situation, and the rationality of this approach needs to be explored

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
  • Method for calculating zero sequence mutual inductive impedance in multiple transmission lines on common tower
  • Method for calculating zero sequence mutual inductive impedance in multiple transmission lines on common tower
  • Method for calculating zero sequence mutual inductive impedance in multiple transmission lines on common tower

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0020] The following is a clear and complete description of the technical solutions in the embodiments of the present invention with reference to the drawings and embodiments. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them.

[0021] In theoretical calculation, for a line with uniformly transposed three-phase parameter symmetry, that is, a balanced transmission line, the positive and negative zero-sequence impedance per unit length can be calculated by the following formula respectively (the unit is Ω / km):

[0022]

[0023]

[0024]

[0025]

[0026]

[0027] In the above formula: R represents DC resistance, and 0.05 is used to represent earth resistance (earth resistance=Z L = π 2 f×10 -4 (Ω / km), when the power frequency is 50Hz, its value is about 0.05), r' represents the equivalent radius of the wire, D g Indicates the equivalent depth of the ground return route, D ave Indicates the geometric ...

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 method for calculating zero sequence mutual inductive impedance in multiple transmission lines on a common tower. The method comprises steps of acquiring basic data related to each loop, a base tower, a power transmission conductor, and a ground wire; equating the soil along the line to the soil resistivity [Rho]t in the same tower section and the soil resistivity [Rho]f in the different tower section; equating the soil of the entire line with a uniform soil resistivity having the same soil resistivity and constructing initial values of [Rho]t and [Rho]f with the uniform soil resistivity; writing a linear algebraic equation group of [Rho]t and [Rho]f for each loop and using an iterative method and the initial values of the iteration to solve [Rho]t and [Rho]f; and according to the basic data, [Rho]t and [Rho]f, obtaining the zero sequence mutual inductive impedance of each type of tower in each loop line and the entire line. The zero sequence mutual inductive impedance and the soil resistivity calculated by the method of the invention can be applied to the research of protection setting calculation, short-circuit calculation, power flow calculation and computer simulation and can greatly improve the accuracy of the analysis and calculation and reduce the error caused by the empirical estimation.

Description

technical field [0001] The invention relates to the field of AC high-voltage transmission systems, in particular to a calculation method for zero-sequence mutual inductance impedance on a multi-circuit transmission line on the same tower. Background technique [0002] The erection of multi-circuit transmission lines on the same tower is an effective means to make full use of transmission corridors, increase transmission capacity, and reduce transmission costs. In actual engineering, in order to ensure the accuracy of the setting value of the relay protection device, the positive (negative) and zero-sequence impedance of each circuit in the multi-circuit transmission line on the same tower usually requires actual measurement. The measurement of line parameters is usually carried out during power outage maintenance. The zero-sequence and positive (negative) sequence impedance values ​​of each circuit can be obtained through measurement. However, since the measurement of zero-s...

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): G01R35/02
CPCG01R35/02
Inventor 刘育权李晓华王莉刘飘曹杰梁子鹏张少凡杨咏梅王聪王历晔
Owner GUANGZHOU POWER SUPPLY BUREAU GUANGDONG POWER GRID CO LTD
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