Download Investigation and Analysis of Electromagnetic Radiation on High

International Conference on Current Research in Engineering Science and Technology (ICCREST-2016)
Investigation and Analysis of Electromagnetic Radiation on High
Voltage Transmission Line
S. Priya 1, Dr. P. Anbalagan 2
1
PG Scholar, 2Assistant Professor,
Department. of EEE, AUT-BIT Campus, Trichy
Abstract— High voltage power lines produce
electromagnetic radiation; this electromagnetic radiation can
cause various health hazards to humans.
Several
developments have taken place in the design of the power
lines such as increasing the distance between Neighboring
transmission lines and the residences decreasing the current,
shielding, changing the geometry of the conductors through
the compaction method, the phase splitting method as well
as the current-phase rearrangement method, to reduce the
radiation. It is important to implement these techniques
because many researchers still suspect the existence of an
association between the EMF induced from power lines and
health damages despite all the studies which failed to prove
the presence of a causal relationship. The main objective of
this work is to give a detailed analysis of the magnetic fields
emitted by 220 kV power transmission lines. The work
starts by an overview on the latest developments in the
power line designs, including recent configurations and the
different ways of conductor placements that help in
reducing the emitted magnetic fields and by a review of the
basic magnetic field equations that will be used later in the
comparison of theoretical and actual values. This work is
implemented by using MATLAB.
ELF-EMFs have frequencies of up to 300 cycles per
second, or Hertz (Hz); for example, the frequency of
alternating current in power lines is 50 or 60 Hz. Cell
phones produce radiofrequency EMFs above the ELF range.
For more information about cell phones, see the NCI Fact
Sheet Cell Phones and Cancer Risk. Electric fields are easily
shielded or weakened by walls and other objects, whereas
magnetic fields can pass through buildings, living things,
and most other materials. Consequently, magnetic fields are
the component of ELF-EMFs that are usually studied in
relation to their possible health effects. Electric and
magnetic fields (EMFs) are invisible areas of energy, often
referred to as radiation, that are associated with the use of
electrical power and various forms of natural and man-made
lighting. EMFs are typically characterized by wavelength or
frequency into one of two radioactive categories:

Non-ionizing: low-level radiation which is generally
perceived as harmless to humans

Ionizing: high-level radiation which has the potential
I. INTRODUCTION
Electric and magnetic fields are invisible areas of
energy that are produced by electricity, which is the
movement of electrons, or current, through a wire. An
electric field is produced by voltage, which is the pressure
used to push the electrons through the wire, much like water
being pushed through a pipe. As the voltage increases, the
electric field increases in strength. A magnetic field results
from the flow of current through wires or electrical devices
and increases in strength as the current increases. The
strength of a magnetic field decreases rapidly with increased
distance from its source. Electric and magnetic fields
together are referred to as electromagnetic fields, or EMFs.
There are both natural and human-made sources of EMFs.
The earth’s magnetic field, which causes a compass to point
North, is an example of a naturally occurring EMF. Power
lines, wiring, and electrical appliances, such as electric
shavers, hair dryers, computers, televisions, and electric
blankets produce what are called extremely low frequency
(ELF) EMFs.
E-ISSN :2348 - 8379
for cellular and DNA damage
Fig. 1 Radiation Spectrum
EMF is Harmful to Health:
During the 1990s, most EMF research focused on
extremely low frequency exposures stemming from
conventional power sources, such as power lines, electrical
substations, or home appliances. While some of these
www.internationaljournalssrg.org
Page 62
International Conference on Current Research in Engineering Science and Technology (ICCREST-2016)
studies showed a possible link between EMF field strength
and an increased risk for childhood leukemia, their findings
indicated that such an association was weak. Now, in the
age of cellular telephones, wireless routers, and portable
GPS devices (all known sources of EMF radiation),
concerns regarding a possible connection between EMFs
and adverse health effects still persists, though current
research continues to point to the same weak association.
Additionally, the few studies that have been conducted on
adults show no evidence of a link between EMF exposure
and adult cancers, such as leukemia, brain cancer, and breast
cancer. Nevertheless, NIEHS recommends continued
education on practical ways of reducing exposures to EMFs.
II. RELATED WORKS
H. Ahmadi et al (2010), has discussed about the
problems and solutions for the electromagnetic fields near
transmission line. The people are highly concerned about
the effects of high voltage transmission lines on their health.
Probable
risk
for
leukemia,
breast
cancer,
neuropsychological disorders and reproductive outcomes
has been reported due to this exposure. In this study, several
measurements around different areas such as overhead
transmission lines, GIS compartments and some appliances
have been conducted and compared with the standard
tolerances. The emphasis of this research is on high voltage
substations and publics. Field magnitudes above 10kV/m
have been measured under wires. Results show that there is
no serious concern for the people living near the
transmission lines but for the individuals who are beneath
those lines for long. Recent achievements about electric
fields’ effect on human health are reviewed.[1]
Girish Kulkarni et al(2012), has suggested about the
proximity effects of high voltage transmission lines on
humans. New threats to humans are observed from
electromagnetic radiation from various sources like mobile
phones, transmission lines and many more. For providing
continuous and uninterrupted supply of electric power to
consumer’s maintenance operation of high voltage power
lines are often performed with systems energized or live.
This is referred as Hot Line maintenance or live line
maintenance in this paper authors are concentrating on
effects due to high voltage transmission lines on persons
involved in this live line maintenance. The main aim of this
paper is to create a model for health hazards in high voltage
transmission lines. In this paper just a theoretical approach
is presented, in coming days the model suggested will be
prepared with ANSYS or MATLAB [3].
Djalel et al (2014) has presented the study of the
influence high-voltage power lines on environment and
human health. The methodology for calculating the
electromagnetic field radiated by the high voltage (HV)
lines and for selection of analytical models that interpret the
electric and magnetic fields as a function of the distance to
the target object. The results were compared with
measurements carried out on site where the HV lines are
E-ISSN :2348 - 8379
present through a neighborhood of a large agglomeration in
the city of Tebessa, for over 50 years. Following published
standards establishing the human to HV power line
distances for professional exposure or in the case of low
frequency field exposure the results obtained by calculations
/simulation and measurement in this work, enable us to
recommend possible solutions for the electromagnetic
pollution issues in the town of Tebessa and thus to reduce
the permanent danger to the public considering also the
legislative vacuum and the poor preoccupation of official
authorities [8].
IV. INVESTIGATION OF EMF IN POWER TRANSMISSION
LINE
Recognizing that there is a great deal of public
interest and concern regarding potential health effects from
exposure to electric and magnetic fields (EMFs) from power
lines, this section provides information regarding EMF
associated with electric utility facilities and the potential
effects of the proposed Project related to public health and
safety. Potential health effects from exposure to electric
fields from power lines is typically not of concern since
electric fields are effectively shielded by materials such as
trees, walls, etc.; therefore, the majority of the following
information related to EMF focuses primarily on exposure
to magnetic fields from power lines.
ELECTROMAGNETIC RADIATION
Electromagnetic radiation (EM radiation or EMR)
is the radiant energy released by certain electromagnetic
processes. Visible light is one type of electromagnetic
radiation; other familiar forms are invisible electromagnetic
radiations, such as radio waves, infrared light and X rays.
Classically,
electromagnetic
radiation
consists
of electromagnetic waves, which are synchronized
oscillations of electric and magnetic fields that propagate at
the speed of light through a vacuum. The oscillations of the
two fields are perpendicular to each other and perpendicular
to the direction of energy and wave propagation, forming
a transverse wave. Electromagnetic waves can be
characterized by either the frequency or wavelength of their
oscillations to form the electromagnetic spectrum, which
includes, in order of increasing frequency and decreasing
wavelength: radio
waves, microwaves, infrared
radiation, visible
light,
ultraviolet radiation, Xrays and gamma rays.
PROTECTION FROM POWER LINE RADIATION
Your best protection from power line health risks is
knowledge, and that may mean taking measurements. If you
have no way of measuring power line radiation levels, it
may help to know that the strongest high voltage
transmission lines (220kV) typically produce less than 0.5
mill gauss EMF at 200 meters. The strongest street pole
power lines (33 kV) generally produce less than 0.5
milligauss at 25 metres. Many street pole power lines are of
www.internationaljournalssrg.org
Page 63
International Conference on Current Research in Engineering Science and Technology (ICCREST-2016)
a lower voltage than this, and their EMF would extend far
less. Power lines vary, so if your house is less than 200
meters from major power lines, or within 25 meters of
street-pole power lines, you may want to use a Low
Frequency Gauss meter suitable for power line radiation
detection [4].
Now we must analyze the transmission tower
characteristics that were given and calculate relative
positioning of all the conductors:
C. PROPOSED SYSTEM
The problem basically gave me the parameters of a
specific transmission line and asked for the electromagnetic
values at a constant height of 1.8 meters from ground
(approximately the height of a person's head), considering
that the person could move on the X axis of a transverse
section of the power line. The electromagnetic field, as the
name says, is made of 2 components, the electric field and
the magnetic field. This work will analyze them separately
in different time instants, both in normal conditions and
hypothetical abnormal or accidental situations
The transmission line being analyzed is a 3-phased, 50
Hz alternating current power line considering a voltage of
400kV and a power of 1200MVA. Each phase is composed
of 2 conductors ("bundled" 2 ways) each one having a
diameter of 31.8 mm. There are also 2 overhead earth wires
or shield wires on the top of the tower, each one having a
diameter of 23.45 mm. All the important distances are
represented on the previous image (in meters). The section
being studied is an area perpendicular to the length of the
conductors, considering 40 m for each side from the center
of the tower (on the X axis) and a height of 50 m from the
ground (on the Y axis).
First some physics. For the magnetic field we have
Ampere’s Law, which is an electromagnetism law that
relates the magnetic field in a closed loop or surface with
the electric current circulating through that same loop:
∮ ⃗. d⃗ =
.i
→ 1
To determine the electromagnetic field of this
transmission line, we're also gonna need to use the method
of images, also known as method of mirror charges. This
method is used as a mathematical tool to solve
electromagnetic problems by adding a mirror image of the
conductor, with the opposite charge, in relation to a
common surface, in our case, the ground. To apply this, we
just replicate the conductors underneath the soil, like the
ground was a mirror, and consider the current on them to be
the same but with opposite direction. The cross inside the
conductors represents the back side of a vector and the point
represents the front side, establishing the sense of direction.
Fig. 4 Transmission Tower Characteristics
Considering the center of the image as the center of the
referential for X and Y. We can now take the coordinates of
all the conductors. I'm also representing them as imaginary
numbers to make mathematical calculations easier. These
are the coordinates for the real and imaginary conductors:
P1a = -d3 + hj
P1ai = -d3 - hj
P1b = -d2 + hj
P1bi = -d2 - hj
P2a = -d1 + hj
P2ai = -d1 - hj
P2b = d1 + hj
P2bi = d1 - hj
P3a = d2 + hj
P3ai = d2 - hj
P3b = d3 + hj
P3bi = d3 – hj
Pg1 = -d4 + hgj
Pg1i = -d4 - hgj
Pg2 = d4 + hgj
Pg2i = d4 - hgj
→ 2
We need the distances between live conductors to
be able to calculate the matrix of the coefficients of
potential.
TRANSMISSION TOWER CHARACTERISTICS
E-ISSN :2348 - 8379
www.internationaljournalssrg.org
Page 64
International Conference on Current Research in Engineering Science and Technology (ICCREST-2016)
Fig.4 Image Conductors
Fig. 5 Input Coordinates to Coefficients
Vertical and horizontal distances are directly
obtained by analyzing the previous image but the diagonal
distances need to be calculated. Having established all the
coordinates is now easier to get them. To get the diagonal
distance you can just calculate the modulus or absolute
value of the difference between 2 points. The distances are:
LINE VOLTAGE
Now we know that the line to line voltage is
400kV, so the instantaneous line to neutral voltage is given
by:
We are also gonna need the distances between live
conductors and the shield wires:
V1(t) = √ .
H1 = |P1a – P1bi| = 60.0013 m
V2(t) = √ .
H2 = |P1a – P2ai| = 60.6132 m
V3(t) = √ .
H3 = |P1a – P2bi| = 60.6712 m
√
√
√
× 103. ej(ω.t)
× 103. ej(ω.t - 2π/3)
× 103. ej(ω.t + 2π/3)
→ 4
H4 = |P1a – P3ai| = 62.4167 m
H5 = |P1a – P3bi| = 62.5281 m
H6 = |P1a – P2bi| = 60.5577 m
→ 3
H7 = |P1a – P1bi| = 62.3076 m
Where omega is the angular speed for a frequency
of 50Hz. Each phase is composed of 2 conductors; therefore
the voltage in each conductor is approximately the same.
Also the shield wires are considered to have 0V. We know
this line has a power of 1200MVA, so we can calculate the
current:
In =
√ .
=
×
√ .
×
= 1732.1 A
→5
For this particular scenario we are considering a
power factor of 1, even though this is obviously not what
happens in reality. Although this is not a real situation, this
consideration shall not change the values of the electric and
magnetic fields, but just change the time instant when they
occur.
What this means is that the values of the final
results are still correct, but their timings might not be the
ones indicated.
1. Line Current
Fig. 4 Distance of Conductors and Shield wires
These are the instantaneous current values for each phase:
I1(t) = √2. In . ej(ω.t)
I2(t) = √2. In. ej(ω.t - 2π/3)
I3(t) = √2. In . ej(ω.t + 2π/3)
→ 6
Since there are 2 conductors in parallel for each
phase, we can consider the current on each conductor to be
aproximmately half of the phase current. Then we can also
assume that the current on the shield wires is 0A, since their
voltage is also 0V.
E-ISSN :2348 - 8379
www.internationaljournalssrg.org
Page 65
International Conference on Current Research in Engineering Science and Technology (ICCREST-2016)
.
=
.
∙
,
<
,
>
2
⎡
⎢
⎢
⎢
⎢
⎢
⎢
⎣
⎡
⎢
⎢
⎢
⎢
⎢
⎢
⎣
⎤
⎥
⎥
⎥
⎥
⎥
⎥
⎦
→7
With all these considerations done, we can finally
start calculating the magnetic field. We have reached the
equation for the magnetic induction
Now we must attend to some factors:
We have seen that the direction of the current on
the phase conductors is the opposite of the direction in the
"image" or mirrored conductors.
This must be represented in the equation with a
mathematical operator, and since the coordinates are
complex numbers, that operator can be just 'j' (I'm using 'j'
as the imaginary unit instead of 'i' to avoid confusions with
the currents).
Other factor we must pay attention happens when
'r' is larger than the radius 'R', because 'r' is the distance
between the point you are analyzing and the conductor,
which is given by a complex number, and the fact that is
being used on the denominator of the equation means that
the direction of the vector is gonna change and it'll give you
a wrong result.
To correct this, in that situation we are going to
use the conjugate of 'r'. \
⎤
⎥
⎥
⎥ .
⎥
⎥
⎥
⎦
→9
Going back to the electric field equation, we now
have the electric charges values, so we can adapt to:
̇n =
. Im ( ̇
.
). ( | ̇ ̇ | - |
̇
̇
|
)
→ 10
By varying X and Y we'll get the values for a
specific area:
E(y, x) = Ep
→ 11
The matrix [A] can now be filled:
⎡
⎢
⎢
[ ]=⎢
⎢
⎢
⎢
⎣
⎤
⎥
⎥
⎥
⎥
⎥
⎥
⎦
And finally, the charges can be obtained by:
⎡
⎢
⎢
⎢
⎢
⎢
⎢
⎢
⎣
⎤
⎥
⎥
⎥
⎥=
⎥
⎥
⎥
⎦
→8
V. IMPLEMENTATION OF PROPOSED SYSTEM
The frequency (f) is 50Hz and the period (T) is 20ms, I
decided to analyze 6 time instants, from 0ms to 8.333ms,
each with an interval of T/12 ms. I'm analyzing just 6
because after those, the values will start repeating, even
though the voltage and current will have opposite values, in
absolute values, they will be the same.
To have some kind of reference here are some common
EMF
values
for
domestic
appliances:




Refrigerator
Stereo
TV
Toaster
- 0,3µT and 90V/m;
- 1µT and 90V/m;
- 2µT and 60V/m;
- 0,8µT and 40V/m;
From this instant on, the graphs will start repeating
themselves, passing through the same situations.
E-ISSN :2348 - 8379
www.internationaljournalssrg.org
Page 66
International Conference on Current Research in Engineering Science and Technology (ICCREST-2016)
By analyzing the figures, it is curious to observe that
sometimes, the center of the tower, at ground level, has
lower EMF values than the sides of the tower, a fact that is
commonly unknown by most, which proves that is safer to
be right beneath than to be just next to it.
Fig. 5.2 Electric Field
Test System 230KV:
Sn
Un
Vg
F
Length
Height
T
H
Hg
D
D1
D2
D3
D4
=
=
=
=
=
=
=
=
=
=
=
=
=
=
1000e6
400e3
0;
50;
40;
50;
0.02/3
30;
35;
0.4;
0.2;
8.4;
8.8;
4.3;
% Current
% Voltage
% Initial voltage
% Frequency
% Width and Height
% the area to analyze
% time instant to analyze
Comparision of MATLAB code Table- I
Output Spectrum of EMF
Magnetic Field
50
Ii =
1.00E+08 A
Vi =
400000 V
T=
0.0067 MA
diameter
0.0318
diameter2
0.0234
In
1.44E+03
Phase i1 =
-1.0206e+03 + 1.7678e+03i
Phase i2 =
2.0412e+03 + 9.0649e-13i
Phase i3 =
-1.0206e+03 - 1.7678e+03i
Phase v1 =
-1.6330e+05 + 2.8284e+05i
Phase v2 =
3.2660e+05 + 1.4504e-10i
Phase v3 =
-1.6330e+05 - 2.8284e+05i
45
40
VI. CONCLUSION
35
Y-axis(m)
30
25
20
15
10
5
0
-40
-30
-20
-10
0
X-axis(m)
10
20
30
40
Fig. 5.1 Magnetic Field
Electric Field
50
45
Although the science is far from conclusive, a
substantial base of data exists from years of research which
is highly suggestive of an association between exposure to
electromagnetic fields and the development of certain health
problems. Identification of these groups aggressed of people
would be impractical given our current state of knowledge,
but their risk would be greater than the general population.
The HV power lines are a source of pollution to the
40
35
Y-axis(m)
30
25
20
15
10
5
E-ISSN :2348 - 8379
0
-40
The power transmission line is one of the major
components of an electric power system. Its major function
is to transport electric energy, with minimal losses, from the
power sources to the load centers, usually separated by long
distances. For the electric field, simulation, the results of
modeling and measurements coincide and give satisfaction.
The difference found between theory and measurement at a
distance of 35-40 m where the B field rebounds
(fluctuation), could be generated by external parameters
such as electric permittivity ε and magnetic permeability µ
of the soil varying from one location to another, also by
climatic and atmospheric conditions such as humidity and
environmental temperature gradients.
-30
-20
www.internationaljournalssrg.org
-10
0
X-axis(m)
10
20
30
40
Page 67
International Conference on Current Research in Engineering Science and Technology (ICCREST-2016)
environment through its direct assault on the landscape, land
use in the city or agricultural land and its impact on human
and animal health by its electromagnetic radiation
REFERENCE
[1] H. Ahmadi, S. Mohseni, A. A. ShayeganiAkmal,
Electromagnetic Fields near Transmission Lines –
Problems and Solutions, Iran J. Environ. Health. Sci.
Eng., 2010, Vol. 7, No. 2 pp. 181-188.
[2] G. Draper , T. Vincent, M.E. Kroll , J. Swanson.
Childhood cancer in relation to distance from high
voltage power lines in England and Wales: a casecontrol study. CCRG, University of Oxford, British
Medical Journal BMJ 04 June 2005.
[3] GirishKulkarni, Dr.W.Z.Gandhare, Proximity Effects of
High Voltage Transmission Lines on Humans, ACEEE
Int. J. on Electrical and Power Engineering, Vol. 03,
No. 01, Feb 2012
[4] M. H. Shwehdi and U. M. Johar, Transmission Line
EMF Interference with Buried Pipeline: Essential &
Cautions, Proceedings of the International Conference
on Non-Ionizing Radiation, pp2, 2003.
[5] Ahlbom A, Day N, Feychting M, Roman E, Skinner J,
Dockerty J. A pooled analysis of magnetic fields and
childhood leukemia. Br J Cancer, 2000,83:692-698.
[6] Nitsch J, Gronwald F, Wollenberg G. Radiation non
uniform transmission line and the partial element
equivalent circuit method. Jon Willey a& Son Ltd 2009
[7] Boorman GA, McCormick DL, Findlay JC, Hailey JR,
Chronic toxicity/oncogenicity evaluation of 60 Hz
(power frequency) magnetic fields in F344/N rats.
ToxicolPathol. 1999. 27:267–278.
[8] Djalel D., Mourad M. (2014), Study of the influence
high-voltage power lines on environment and human
health (Case Study: The electromagnetic pollution in
Tebessa city, Algeria), Journal of Electrical and
Electronic Engineering, 2(1), 1-8.
[9] R. W. P. King, D. Margetis, The Low-Frequency
Electric Fields Induced In A Spherical Cell Including
Its Nucleus, Progress In Electromagnetics Research,
PIER 36, 61–79, 2002
[10] Desjobert H, Hillion J, Adolphe M, Averlant G,
Nafziger J. Effects of 50 Hz magnetic fields on Cmyc
transcript levels in non synchronized and synchronized
human cells. Bioelectromagnetics. 1995. 16 :277- 283.
[11] Dockerty JD, Elwood JM, Skegg DC, Herbison GP.
Electromagnetic field exposures and childhood cancers
in New Zealand. Cancer Causes Control; 1998. 9 : 299309.
[12] R Matthes, A McKinlay, J Bernhardt Eds. Exposure to
static and low frequency electromagnetic fields,
biological effects and health consequences (0-100 kHz).
ICNIRP.2004.
[13] Ivancsits S, Diem E, Pilger A, Rudiger HW, Jahn O.
Induction of DNA strand breaks by intermittent
exposure to extremely-low-frequency electromagnetic
fields in human diploid fibroblasts. 2002. 519 :1-13.
E-ISSN :2348 - 8379
[14] Ivancsits S, Diem E, Jahn O, Rudiger HW. Age-related
effects on induction of DNA strand breaks by
intermittent exposure to electromagnetic fields. Mech
Ageing Dev 2003.124:847-50.
[15] Ivancsits S, Diem E, Jahn O, Rudiger HW. Intermittent
extremely low frequency electromagnetic fields cause
DNA damage in a dose-dependent way. Int Arch Occup
Environ Health, 2003. 76:431-436.
www.internationaljournalssrg.org
Page 68