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Title of Presentation

Conductors used in
Electrical Power System

Subject Lecturer: Sir Ateeq Ahmed Baig
Subject Name: Power System Analysis
Group Members
11-EE-20
11-EE-36
11-EE-52

Zohaib Mirza
Bilal Muneer
Madasar Latif

General Considerations for T/L
Conductors
The conductor material used for transmission and distribution of
electric power should have the following properties :
(1) high electrical conductivity
...

(3) low cost so that it can be used for long distances
...

All above requirements are not found in a single material
...


Commonly Used Conductor Materials
The most commonly used conductor materials in
Electrical Power System
• Copper
• aluminium
• steel-cored aluminium
• galvanised steel
• cadmium copper
...


1
...
However, due to its
higher cost and non-availability, it is rarely used
for these purposes
...


2
...

• Aluminium has much smaller conductivity and
tensile strength
...
For the same resistance, the
diameter of aluminium conductor is about 1·26
times the diameter of copper conductor
...
,
aluminium has an edge over copper
...
It is
particularly profitable to use aluminium for heavy
current transmission
...
Steel cored aluminium
Due to low tensile strength, aluminium
conductors produce greater sag
...
In
order to increase the tensile strength, the
aluminium conductor is reinforced with a core of
galvanised steel wires
...
C
...
R
...


The steel cored aluminium conductors have the
following advantages :
(i) The reinforcement with steel increases the tensile
strength but at the same time keeps the composite
conductor light
...

(ii) Due to smaller sag with steel cored aluminium
conductors, towers of smaller heights can be used
...
Galvanised steel
...
Therefore, galvanised
steel conductors can be used for extremely long spans or
for short line sections exposed to abnormally high stresses
due to climatic conditions
...
Due to poor conductivity and high
resistance of steel, such conductors are not suitable for
transmitting large power over a long distance
...


5
...


The conductor material now being employed in certain
cases is copper alloyed with cadmium
...
Therefore,
cadmium copper conductor can be useful for
exceptionally long spans
...
e
...
Cadmium copper is also used
in those areas where there is ammonia gas , because
aluminium reacts with ammonia and corrodes
...

AAAC : All Aluminium Alloy conductors
ACSR : Aluminium conductors, Steel-Reinforced
ACAR : Aluminium conductor, Alloy-Reinforced
AACSR : Aluminum Alloy Conductor Steel
Reinforced

AAC (ALL ALLUMINIUM CONDUCTORS)
AAC is made up of one or more strands of hard drawn 1350
aluminium alloy
...
AAC has seen extensive
use in urban areas where spans are usually short but high
conductivity us required
...

Because of its relatively poor strength to weight ratio, AAC had
limited use in transmission lines and rural distribution because of
long spans utilized
...

These conductors are designed to get better strength to weight ratio and
offer improved electrical properties, excellent sag-tension characteristics,
and superior corrosion resistance when compared with ACSR
...
The core can be
single wire or stranded depending on the size
...

• ACSR conductors combine the light weight and good conductivity
of aluminium with the high tensile strength and ruggedness of
steel
...


Features of ACSR
•
•
•
•

high Tensile strength
better sag properties
economic design
best suited for transmission lines with long spans

1350-H19 Aluminium SPECS

2- Aluminum Conductor Steel
Reinforced (ACSR)

1- Steel strands
2- Aluminum strands

Code names and technical data for
ACSR

ACAR (Aluminium Conductor Alloy Reinforced)
•

•

Aluminium Conductor Alloy Reinforced (ACAR) is formed by concentrically
stranded wires of Aluminium 1350 on high strength Aluminium Magnesium -Silicon(AlMgSi) alloy core
...

ACAR has got a better mechanical and electrical properties as compared
to an equivalent ACSR, AAC or AAAC
...
These conductors are extensively used in
overhead transmission and distribution lines
...
The core can be of either single wire or
stranded multi wire
...

Additional corrosion protection is available through the application of
grease to the core or infusion of the complete cable with grease
...


Features
•
•
•
•

offers optimal strength for line design
...


Applications

The all aluminum alloy conductor steel reinforced is used for the power
transmission lines with large span length installed under various severe weather
conditions like snow, ice, storms, and so on
...
Variable steel core stranding enables the desired strength to be achieved
without sacrificing ampacity
...
00 mm
and 30-Strands of Aluminium of dia 3
...
18 mm
and 54-Strands of Aluminium of dia 3
...


(iii) for 400 KV
lines

: Twin 'Moose' ACSR having 7-Strands of steel of dia 3
...
53 mm
...
e
...
00
mm dia plus 12-Aluminium strands of 3
...

• For 220 KV Lines:
Special 'DEER' conductor, having 17-Strands of Steel of dia
2
...
65 mm dia
...
Corona occurs when the surface potential gradient of a conductor
exceeds the dielectric strength of the surrounding air
...
Corona produces power loss
...
Implementing Extra High Voltage has advantage of
reduction in the copper losses and improves efficiency
...
In order to reduce corona effect hollow round conductors
are used
...
For transmission of power beyond 230kV bundled conductors are
employed

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