On the Eddy Current Losses in Metallic Towers

Ibrahim Mahariq,Huda Mohammed,Svetlana Beryozkina,Hamza Kurt

doi:10.14710/ijred.9.1.1-6

Abstract

The existence of magnetic field around high-voltage overhead transmission lines or low-voltage distribution lines is a known fact and well-studied in the literature. However, the interaction of this magnetic field either with transmission or distribution towers has not been investigated. Noteworthy it is to remember that this field is time-varying with a frequency of 50 Hz or 60 Hz depending on the country. In this paper, we studied for the first time the eddy currents in towers which are made of metals. As the geometrical structures of towers are extremely complex to model, we provide a simple approach based on principles of electromagnetism in order to verify the existence of power loss in the form of eddy currents. The frequency-domain finite difference method is adapted in the current study for simulating the proposed model. The importance of such a study is the addition of a new type of power loss to the power network due to the fact that some towers are made of relatively conductive materials.©2020. CBIORE-IJRED. All rights reserved

Highlights

It is a well-known fact that some of electrical energy generated and supplied to a distribution utility does not reach to the end consumer
The eddy current density induced in a metal due to a magnetic field produced by a currentcarrying conductor is:
In this paper we presented a method for analyzing the eddy current in transmission towers that it can be applied to any type of towers by segmenting the tower to small parts for the facilitation of the numerical calculation, and saving memory and time

Summary

Introduction

It is a well-known fact that some of electrical energy generated and supplied to a distribution utility does not reach to the end consumer. Steel needs less maintenance compared to other material types These towers are interacting with the magnetic field produced by the current carrying conductors of the three-phase transmission line (Ryan 2001). Liu et al (1996) discussed the environmental effects due to transmission lines using charge simulation method as a means of calculating the magnetic field around the three phase conductors. Hwang (1997) applied finite element method to calculate the forces and eddy current losses induced in the structural steel that always run parallel to the three-phase line which is used to provide mechanical protection for the current lines. By using the finite difference method for solving Maxwell’s differential equations in low frequency problems, the resulting eddy-currents losses in the tower are estimated at different material properties.

Formulation of Eddy Currents

Finite Difference Discretization

Results and Discussions

Conclusion