Longitudinal variations of very-low-frequency chorus activity in the magnetosphere: Evidence of excitation by electrical power transmission lines

1977 ◽  
Vol 4 (7) ◽  
pp. 275-278 ◽  
Author(s):  
J. P. Luette ◽  
C. G. Park ◽  
R. A. Helliwell
Keyword(s):  
Transmission Lines ◽  
Power Transmission ◽  
Electrical Power ◽  
Low Frequency ◽  
Power Transmission Lines ◽  
Very Low Frequency ◽  
Longitudinal Variations

scholarly journals CALCULATION OF POWER LINE FIELDS BETWEEN CIRCULAR CONDUCTORS

2012 ◽  
Vol 04 (01) ◽  
pp. 1250025
Author(s):  
ANDREW SEAGAR ◽  
SALAKCHIT NILBOWORN
Keyword(s):  
Electric Field ◽  
Transmission Lines ◽  
Power Transmission ◽  
Circular Cross Section ◽  
Low Frequency ◽  
Test Cases ◽  
Power Transmission Lines ◽  
System Matrix ◽  
High Voltage Direct Current ◽  
Frequency Components

It is important to calculate the electric field at the surface of high voltage direct current power transmission lines, since it is this field which governs the onset of corona discharge and the power loss arising therefrom. A method is presented here to calculate the electric field based on an implementation of the boundary element method for conductors of strictly circular cross section. Given the circular geometry it is possible to resolve all integrals involved analytically. A Galerkin approach is adopted, giving the solution in the spatial frequency domain. That allows a controlled truncation of the system matrix by choice of which frequency components to keep. It transpires that the low frequency components are the most important ones. Two test cases are used to quantify the accuracy of the solution with respect to truncation and distance from the surface. It is found that the accuracy increases with distance from the surface, but for all distances can be controlled by choosing an appropriate level of truncation.

scholarly journals Analysis of Lightning Performance on 345 kV Transmission Lines Using Python Programming

2020 ◽  
Vol 3 (3) ◽  
pp. 65-76
Author(s):  
Fri Murdiya ◽  
Rofi Hariadi
Keyword(s):  
Transmission Lines ◽  
Power Transmission ◽  
Electrical Power ◽  
Object Oriented Programming ◽  
Computer Application ◽  
Lightning Strike ◽  
Percentage Error ◽  
Power Transmission Lines ◽  
Shielding Failure ◽  
Python Programming

One of main causes of interruption of electrical power supply is the lightning strike on overhead power transmission lines. The lightning performance of transmission line can be determined by value of shielding failure flashover rate (SFFOR) and back flashover rate (BFOR). The object of this study is to create a computer application to compute lightning performance on the transmission lines using Python programming. Pythons package tkinter used for program interface window. Application programming is done by using the concept of object-oriented programming (OOP) using Pythons keyword class. Validation shows that the application has applied the method correctly with a percentage error 0 % for SFFOR and 3.14 % for BFOR. The application can do analysis on the factors that affecting SFFOR and BFOR such as the effect of thunder day, tower foot resistance, and number of isolator disk. The results obtained in this study is computer application that can perform lightning performance analysis and analysis of factors that can affect it, such as thunder day, tower foot resistance and the number of isolator disk.

scholarly journals Corona Loss Minimization on High Voltage Transmission Line Network using Bundled Conductors.

2020 ◽  
Vol 9 (3) ◽  
pp. 887-891
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Power Transmission ◽  
Hessian Matrix ◽  
Electrical Power ◽  
Power Transmission Lines ◽  
Long Distance ◽  
Power Stations ◽  
Line Network ◽  
Corona Losses

Electrical power generated and transmitted at a long distance away from the power stations is usually affected by inherent transmission line losses. The Ohmic and Corona losses which are predominantly common in power transmission lines are considered in this paper. These two losses are mathematically modeled with and without embedded bundled conductors. The resultant model which is a non-linear multivariable unconstrained optimized equation is minimized using the Hessian matrix determinant method for stability test purposes. The results obtained show that corona losses are minimized with embedded bundled conductors at a very low current value with large spacing distance between the bundled conductors. The decrease in the corona loss which is a consequence of spacing adjustment of the 2, 3, and 4 strands of bundled conductors was plotted using MATLAB 7.14. The plots obtained are in conformity with the inverse relation between corona loss and conductor spacing.

Study on Dynamic Simulation of 4-Bundle Ice-Coated Conductor Galloping Based on 3-D Model

2011 ◽  
Vol 105-107 ◽  
pp. 474-477
Author(s):  
Shi Jing Wu ◽  
Zeng Lei Zhang ◽  
Zhen Hao Liu ◽  
Ji Cai Hu
Keyword(s):  
Transmission Lines ◽  
Power Transmission ◽  
Low Frequency ◽  
Element Model ◽  
Wake Flow ◽  
Power Transmission Lines ◽  
Ansys Software ◽  
Frequency Coupling ◽  
D Model ◽  
The Finite Element Model

Galloping of power transmission lines is a low frequency self-oscillation with large amplitude. The aerodynamic effect on each sub-conductor of 4-bundle conductor is different due to wake-flow-influence. In order to explore the reasons leading to galloping, a 3-D model for power transmission line is built. A two-node quadratic beam element in 3-D and a structure mass element are applied to establish the finite element model of iced 4-bundle conductor in ANSYS software. Then dynamic transient response calculations are made on this model. According to the results, difference in vibration of sub-conductors and frequency coupling of torsional and transverse vibration can be confirmed. The simulation results illustrate the wake-flow-influence effect and the coupled motions effect on galloping of 4-bundle conductor.

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