High Temperature Conductors
Sterlite Technologies Limited
Disclaimer
Certain words and statements in this communication concerning Sterlite Technologies Limited and its prospects, and
other statements relating to Sterlite Technologies’ expected financial position, business strategy, the future
development of Sterlite Technologies’ operations and the general economy in India & global markets, are forward
looking statements.
Such statements involve known and unknown risks, uncertainties and other factors, which may cause actual results,
performance or achievements of Sterlite Technologies Limited, or industry results, to differ materially from those
expressed or implied by such forward-looking statements.
Such forward-looking statements are based on numerous assumptions regarding Sterlite Technologies’ present and
future business strategies and the environment in which Sterlite Technologies Limited will operate in the future.
The important factors that could cause actual results, performance or achievements to differ materially from such
forward-looking statements include, among others, changes in government policies or regulations of India and, in
particular, changes relating to the administration of Sterlite Technologies’ industry, and changes in general economic,
business and credit conditions in India.
Additional factors that could cause actual results, performance or achievements to differ materially from such
forward-looking statements, many of which are not in Sterlite Technologies’ control, include, but are not limited to,
those risk factors discussed in Sterlite Technologies’ various filings with the National Stock Exchange, India and the
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A growing need for efficient power
transmission networks ….
With increased private participation in power generation, transmission & distribution in
India, alongside that of legacy incumbents, there is a robust demand for bare overhead
power conductors.
The evident challenge is:
(a) To transmit more power over existing lines and
(b) Development of more efficient power conductors for new lines.
Building of efficient power transmission systems is a national priority.
3
Innovative solutions for efficient power
transmission systems
4
Increasing demand for Electrical Power
Generation & Transmission, but…..
• Very high cost to install
new Power lines.
• Difficulty in acquiring
Tower sites – Right of way .
• Time involved in
constructing new Power
lines.
• Provision for future
contingencies
Usage of High
Temperature – Low
Sag (HTLS) Conductors
Capacity Enhancement:
Transmission Line
Higher
Voltage
Trans. System
Capacity
Enhancement
Bundle
Conductor
Size Up
Conductor
Advanced
Material
AL59
TACSR
ACSS
STACIR
Hence, Shift From ACSR to HTLS
High current carrying capacity
Ampacity
Conductor Cost
Low Line loss
Low Sag-Tension
Property
Economics
Sag-Tension
HTLS
Conductors
Easy & rapid
installation
Long – Term
reliability
Reliability
Installation
High Ampacity Conductors
Low Resistance Conductors
AL59 Alloy Conductors
1120 Alloy Conductors
EHC Alloy
Dull Surface Finish
Dull Conductor
Colored Conductors
High Temperature (HTLS) Conductors
ACSS (Aluminium Conductor Steel Supported)
TACSR (Thermal Alloy Conductor Steel Re-inforced)
STACIR (Super thermal Aluminium Conductor Invar
Reinforced)
ACCC (Aluminium Conductor Composite Core)
ACCR (Aluminium Conductor Composite Reinforced)
Specialty materials.
Superior performance.
A range of specialty alloys offer superior thermal resistance that improves the efficiency
in high current transmission.
9
AL59 Conductor
 26% to 31% more current carrying capacity as
that of ACSR of the same size, while maximum
sag remains the same & working tension is lesser
than that of ACSR.
 Resistivity is substantially lesser than that of
ACSR/AAAC conductors, resulting in lower I2R
losses.
 Higher corrosion resistance than 6201 alloy
series (AAAC).
* Source: CPRI Report on AL59 Conductor vide Study on AL59 Conductor at CPRI Laboratory,
Bangalore.
Higher Current Carrying Capacity – AL59
1600
Amperes
1400
ACSR
Alloy
1200
AL-59
Alloy1120
1000
EHC
800
600
65
70
75
80
85
90
Degrees C
AL-59 provides Higher Ampacity
95
100
ACSS – Aluminium Conductor Steel Supported
CONSTRUCTION:
ACSS Aluminium wires are manufactured from Annealed Aluminium 1350 wires. The conductor
comprises of an inner core of Galfan (Zn 5% Al Mischmetal) coated steel wire and concentrically
arranged annealed Aluminium strands forming the outer layers of the conductor
APPLICATION:
ACSS Conductors are used for both up gradation and for new power transmission and distribution
lines.
Annealed Aluminium 1350 wire
Fully annealed Aluminium is having lower yield strength, resulting into inelastic elongation in
Aluminium wire when tension is applied on a composite conductor.
•
Annealed Aluminium wire can operate
continuously up to 2500C without any
loss in strength
•
When stressed, the complete conductor
Aluminium elongates and transfers all
the load to steel core
•
Lower compressive forces between
annealed Aluminium and Steel Core
enables higher self damping capacity
because of this increased elongation in
annealed Aluminium
Properties
HAL (Hard
drawn 1350
Al)
Annealed
Aluminium
1350
160
60
Conductivity
%IACS
61
63
%
Elongation
1.2 to 2
25 to 30
Conductor
ACSR
ACSS
Ampacity
1X
2X
Tensile
Strength in
(Mpa)
Generally for ACSS Conductor mfg, bobbins in stranding machine are to be kept with minimum
tension. Sterlite adopted a new annealing process which enables to run the machine at same
tension.
Mischmetal Steel Wire
The Mishmetal Coating on the steel core can withstand for continuous operating temperature
upto 2500C
•
•
•
Mechanical and physical properties of
Mishmetal steel wire are similar to that
of the galvanized steel wires
Properties
Galvanized
Steel
Galfan
Steel
Corrosion resistance of Mishmetal steel
wires are better than that of galvanized
steel wires
Tensile
Strength in
(Mpa)
1410
1410
% Elongation
4
4
ASTM B 802 and B 803 were developed in
1989 defining requirement of the core
wire using this different coating
Continuous
temperature
at which
coating
withstands
(Deg C)
150
250
ACSR
ACSS
Conductor
TACSR– Thermal Alloy Conductor Steel Reinforced
CONSTRUCTION:
Thermal-resistant Aluminum-alloy Conductor, Steel Reinforced (TACSR) conductors wherein the
inner core is composed of galvanized steel and the outer layers are composed of thermal-resistant
aluminum-alloy.
APPLICATION:
TACSR conductors are used to enhance the capacity of the existing transmission line by simply
replacing the existing conductor without any modifications to the tower. Also used for new lines
where power transfer requirement is very high.
STACIR – Super Thermal Alloy Conductor
Invar Reinforced
CONSTRUCTION:
Super thermal alloy (STAL) are manufactured from Al-Zr (Aluminium Zirconium) alloy rods. The
conductor comprises of an inner core of Aluminium clad Invar (36%Ni in steel) and concentrically
arranged STAL strands forming the outer layers of the conductor
APPLICATION:
STACIR/AW conductors is preferred for re-conductoring applications. The capacity of the existing
transmission line can be enhanced by simply replacing the existing conductor without any
modifications to the tower.
16
Thermal Alloy (s)
Super thermal alloy contains Zr which deposits over the grain boundary of Aluminium,
thus increasing the recrystalisation temperature of Aluminium which enables STAL to
operate at high temperature without any loss in strength.
Properties
HAL (Hard drawn
1350 Al)
TAL (Thermal
Alloy Al-Zr)
STAL (Super
Thermal Alloy
Al-Zr)
Tensile Strength
in (Mpa)
160
160
160
Conductivity
%IACS
61
60
60
Continuous
Operating
Temperature
80
150
210
Emergency
Operating
Temperature
120
180
280
Conductor
ACSR
TACSR
STACIR
Ampacity
1X
1.5X
2X
Inner Core – TACSR & STACIR
STACIR is designed with Aluminium clad invar having low thermal co-efficient of
expansion at 2100C which enables it to maintain the SAG equal to equivalent ACSR.
TACSR can be designed with STC 6 core to maintain the sag equal to ACSR, even while it
operate at 1500C.
Properties
Galvanized Steel
Galvanized
Steel (ST6 C)
Aluminium Clad
Invar
Tensile Strength
in (Mpa)
1226
1700
1184
8
8
14
11.5x10-6
11.5x10-6
3.7x10-6
Young's Modulus
(Kg/mm2)
21000
21000
15500
Conductor
ACSR
TACSR
STACIR
Ampacity
1X
1.5X
2X
Conductivity
%IACS
Linear Coefficient of
Expansion
Technical Comparison:
ACSR Moose
AL59
(ACSR Moose
Equivalent)
EC 1350
Al 59 Alloy wires
ST1 A Galvanized
Steel
Al 59 Alloy wires
54Al/3.53 mm
7st/3.53 mm
61Al/3.52 mm
31.77
31.68
31.62
31.77
31.77
597
593
591
597
597
Minimum breaking load as per
ST6C Core (kgf)
16184
14576
14271
18043
15549
Weight (kg/km)
2004
1640
1983
2004
1956
DC resistance (Ohm/km)
0.05595
0.0501
0.05477
0.05651
0.05409
Current carrying capacity
(Amperes)
876
1098
1950
1650
2078
Maximum continuous
operating temperature (0C)
85
95
250
150
210
Particulars
Aluminum type
Core type
Stranding
(Aluminum / Core)
Diameter (mm)
Cross section area (mm2)
ACSS
(ACSR Moose
Equivalent)
TACSR
(ACSR Moose
Equivalent)
STACIR
(ACSR Moose
Equivalent)
Annealed
Aluminium Wires
ST6 C/ST 1A
Galvanized steel
wire
54TAL/3.513 mm
7st/3.513 mm
Heat Resistance
Al Alloy
Super Thermal
Aluminium alloy
ST6 C
Aluminium Clad
Invar wire
54TAL/3.53 mm +
7st/3.53 mm
54STAL/3.53 mm
7Invar/3.53 mm
Use of High Ampacity conductors can result in saving in CAPEX
Technical Comparison: Current Carrying Capacity
ACSR Moose
ACSS
(ACSR Moose
Equivalent)
Current Carrying Capacity (Amperes)
876
1950
Current Carrying Capacity (Twin)
1752
3900
Current Carrying Capacity (Quad)
3504
7800
Same Current Construction
Quad
Twin
Total Conductor Weight (Per Circuit)
24048
11898
-
50%
Particulars
Savings in Weight (%)
Manufacturing Capability - Sterlite
21
Sterlite In-house Facility – HTLS Conductors
Special Features
Aluminium / STAL Rods
Rolling Mill
Precise High Speed
Wire Drawing Machines
Furnace for
Aging / Annealing (ACSS)
61 Rigid Strander (with Auto
Batch loading system) for
Higher Transmission Sizes
05 – Rolling Mill
17 – Wire Drawing Machines
37 Rigid Strander for
Medium Transmission Sizes
03 – Ageing Furnace
01 – Anealing Furnace
19 Rigid Strander
08 – 61 Rigid Strander
03 – 37 Strander
02– 19 Strander
08 – Skip Strander
High Speed Skip 7 Strander
for Distribution Sizes
• State of the art Properzi
Rolling Mill with
computerized process
control and hence precise
and accurate product.
• Auto Tension devices for
each bobbin of the Rigid
Stranders.
• High Speed Stranding @
40 to 50meter/min
• Inbuilt Conductor
automatic Greasing System
• Special designed
machine for making Dull
Conductors
•In-house
facility/technology for
making STAL alloy
New Products Developed
Product
Special properties/
Usage
Approved / Type tested at
AAAC ASTER 570 (61/3.45mm)
High conductivity and high strength
compared to 6201 AAAC
EDF,France
Al 59 (61/4.02)
Strength in-between 6201 AAAC
and AAC and conductivity nearly
equal to E.C grade
JPOWER,Japan
E.H.C
AAAC Araucaria (61/4.17)
Super high conductivity and Super
high strength compared to 6201
AAAC
SAG,Germany
ACSR/AS Dove (26Al/3.71+7St/2.89)
Aluminium clad steel instead of
galvanized steel which increases the
current carrying capacity of the
conductor compared to ACSR
JPOWER, Japan
1120 Sulfur Conductor (61/3.75mm)
Strength in-between 6201 AAAC
and AAC and conductivity nearly
equal to E.C grade
SAG, Germany
5/20/2010
23
New Products Developed.. Continued..
Product
Special properties/
Usage
Approved / Type tested
at
STACIR Moose
For Uprating Lines; can
operate up to
210
Deg C
Kinertics Canada
ACSS Curlew
For Uprating and New
Lines; can operate up to
250 DegC
Tag Corporation, Chennai
TACSR
For Uprating Lines; can
operate up to 250 DegC
Tag Corporation, Chennai
Summary
25
Benefits in performance and costs
For re-conductoring:
• Enhanced current carrying capacity.
• No modification / reinforcement to existing towers.
• Cost effectiveness.
For new lines:
• Enhanced current carrying capacity.
• Reduction in overall capital expenditure.
• Reduction in overall operating expenditure
• Higher corrosion resistance.
• Shorter project duration.
CBIP
26
Sterlite’s offerings:
Diverse range of applications
NEW LINES
RECONDUCTORING
AL59
AL59
1120
1120
TACSR
TACSR
ACSS
ACSS
STACIR
Other New Solutions: Dull, TW, Gap Type Conductors
3rd Annual Conference on Power Transmission in India
27
Thank You
Connecting every home on the planet…
Workshop on
Latest Technologies in Power Transmission Sector
Organised By
CBIP
20th May, 2010
Fault Location Session
Travelling Wave System (TWS)
By
Sudhanshu Gupta
What are we doing?
Double ended accurate fault location system for interconnected transmission lines
Permanent and
Intermittent Faults
X
X
X
X
>100KV
TWS
X
X
DSFL
Typical Application
Categories of Fault
Faults can be divided into three types
• Permanent faults – normally rare but need finding and fixing
fast
• Intermittent faults – can be re-closed but can occur again. Eg
damaged insulation, vegetation
• Transient faults – can be re-closed. Caused by random events
eg lightning, bush fires.
Intermittent and transient faults were not taken too seriously
but there is an increasing awareness over power quality and
system stability issues that are driving a need to reduce the
number of line trips.
You need accurate fault location to find these faults
The need for fault location
It is generally accepted that accurate fault location on overhead
lines is necessary at transmission voltages (>100KV) to:
• Reduce downtime
• Allow the implementation of preventive maintenance at known
trouble spots to avoid further trips and voltage dips
• Reduce costs and manpower requirements – no need for multiple
line patrols or use of helicopters.
• Minimises extra costs involved in maintaining system security
during the plant outage.
The traditional methods of fault location have been based on
impedance techniques now commonly incorporated in digital
relays and fault recorders.
Problems with Impedance
Impedance techniques have been used for the past 35 years. They
are now conveniently available in digital protection relays and fault
recorders. Problems arise when:
• The fault arc is unstable
• The fault resistance is high and fed from both ends
• Circuits run parallel for only part of the route
Accuracy is dependent on:
• PT and CT response
• The assumption that the line is symmetrical
• A lumped equivalent circuit used in the algorithms
•Filtering of harmonics and DC offsets – more difficult with reduced
data window caused by faster clearance times (5 cycles or less)
•Line parameters
Accuracy of Impedance
Typically 1 to 20% of line length but it can be worse
depending on fault type.
Phase to phase faults give best performance.
Phase to earth faults with high fault resistance can result in large errors.
Actual error increases with line length.
Compensation required for mutual coupling on double circuit lines
Compensation required for end source impedance.
On a 200Km line the error could be from 2Km to 40Km
There is a need for a better system
Application of TWS (Traveling wave
system)
• Best on interconnected overhead lines
• Uses a double ended technique to allow automatic calculation and
display of fault position
• Accuracy not affected by the factors that cause problems to
impedance methods
• Accuracy not affected by line length
• Works for all types of faults including open circuit faults
• Works on series compensated lines, lines with tapped loads, lines
with lengths of underground cable and teed circuits
Double Ended Method of TWS Fault Location
T1A
A
The distance to fault
is proportional to
the difference in
arrival time (T1A –
T1B), the length of
line (La+Lb) and the
propagation velocity
La
A
Fault
Lb
Traveling waves
generated by the
fault propagate along
the line in both
directions
TWS devices
installed at line
ends trigger on
the arrival of the
wave and assign
an accurate time
tag
B
T1B
La = [(La+Lb) + (T1A-T1B).v] / 2
V for air insulation = 300m/μs
How it works
TWS Accuracy
Time stamp accurate to 1μs
It is fortunate and somewhat convenient that at
the speed of light, one micro-second equals
300 m (975 feet)
It is fortunate and somewhat convenient that
300 m (975 feet) equals the average span
length on a transmission line.
The result is repeatable fault location
within 1 tower / span on all types of
fault. Measurements from both ends
gives accuracy 150m
TWS Implementation
TWS Implementation
Secondary clamp on sensors
Install while energized
No line outage required
TWS Implementation
TWS Implementation
Example of Distance to Fault Results
from our PAD software
Result from Malaysia
Automatic DTF Calculation using Double Ended Type D Method
via TWS Base Station 2000 software
TWS Fault Location to One Span - Works Even
When Impedance Methods have Large Errors
Send the repair teams to the right place. Minimize search time and
reduce expensive downtime
What is the actual cost of inaccuracy?
TWS accuracy in all types of weather
Works in fog and at
night when
helicopters cannot
Why risk multiple line patrols over dangerous terrain when you can go
straight to the spot?
TWS One span accuracy locates damaged
insulators
Question:
A structure experienced 4 self-clearing faults in
1 year. Is it in the best interest of your
company and reliability to visually inspect that
structure for damage that may eventually result
Question:
in a non-clearing fault?
A structure experienced 4 self-clearing
faults in 1 year. Is it in the best interest of
your company and reliability to visually
inspect that structure for damage that may
Not possible to pinpoint damage with impedance methods
eventually result in a non-clearing fault?
due to inconsistency of results and variable errors
TWS Accurate enough to locate fault damage
caused by bird streamers
Assess damage and organise repairs
One span accuracy tracks down tree
problems
Go straight to cause of problem to take remedial action and avoid
further trips
TWS accuracy pinpoints lightning faults
Vital information when deciding
whether to reclose a line
• Compare lightning strike
information from the IEEE Fault
And Lightning Location
System (FALLStm) against
exact TWS fault location to:
• Confirm lightning is fault cause:• The TWS trigger was caused by
an actual lightning strike on the
line
• Confirm lightning is not the fault
cause:• The TWS trigger was caused by
induced lightning activity, but not
a direct hit
Track faults from ground fires
Compare GPS fire coordinates
against exact TWS fault
location to:
Confirm ground fire is fault
cause
Confirm ground fire is not fault
cause
Vital information when deciding whether to reclose a line
Can the TWS be used as a single ended
fault locator?
NO except under special circumstances
•
•
The line being monitored is very short compared to the other
lines connected to the busbar
The transmission system is very simple minimising the
number of reflections
Even with the above the operator must be skilled at interpreting
TWS waveforms and be prepared that sometimes they will get a
wrong answer!
We only promote the TWS as a double ended system
Measurement of line length
• The TWS is triggered by energising a dead line
• The waveform is analysed and line length measured by identifying a
reflection from the far open circuit end
• A good method to check the length of the line including sags and
changes in elevation
• Known as a Type E test
A precise line length checks improves TWS fault
location accuracy and maximises the benefits
Type E Method for confirming line length
Often used on a trial to show the system is
working
END A
x
Far end must be open and isolated
(mechanical break with a disconnector)
L1
Closing the circuit breaker
at End B to energise the
dead line launches a wave
that reflects from the far
open circuit end
L2
x
T2
END B
Line Length = [T2 x v]/2
Result from Nigeria
Type E Test – Line re-energised from TWS1 end with far
end of line open and isolated
TWS Deployment – General Rules
• TWS must be located at a substation where more than one line is
connected to the busbar if linear couplers are used.
= TWS line module (current)
TWS can be located at a line end but the voltage component of the wave
must be monitored, not the current
= TWS line module (voltage)
= TWS line module (current)
TWS Deployment – General Rules
Only allow a maximum of one tee connection between two TWSs
One T only
= TWS line module (current)
Remember – a TWS system must have a good
comms infrastructure for practical double ended
operation
Two types of substations
Centralised Relay Room
Distributed Relay Rooms
Good for TWS – LC connection <25m
Good for DSFL
All relay panels in one room
adjacent to each other
Secondary wiring
X
X
Central services – control,
comms, batteries
Wiring for Indications
X
X
Relays
X
Relays
X
Relays
Results Analysis – 3 x Software Sets
NFE – configures TWS network
Saves files to TWSBase2000
TWS Base2000 – manual connection
to TWS devices. Download, save,
display and analyse index files and
waveforms. Calculation of DTF
Communications to TWS
PAD – automatically polls DSFL
devices, calculates and displays
DTF results. Logs comms errors and
GPS lock issues
TWS
PAD software - Fast, Automatic Listing of
Exact Fault Position
• Results displayed shortly after a line trip – no operator
intervention required
• No need to wait for a protection engineer to analyze the data
• Results emailed to maintenance departments to get repair
crews moving faster.
• Option to terminate polling and get results from a single circuit
on demand after a line trip in 4 clicks
• The health status of the fleet of TWS can be seen at a glance
Results available where and when they are needed
without the intervention of skilled operators
Simplified display of Distance to Fault
Results
Results automatically displayed shortly after a line trip
providing vital information for the decision to reclose
Structure ID
can be
imported and
displayed
Simplified Display of System Alarms
Allows communication problems to be quickly identified
so they can be rectified. Provides details of the integrity
of the GPS time synchronization to warn of intermittent
or more serious problems
Network File Editor – a tool to configure a TWS
fault location system
• A graphical user interface (GUI) to configure a fleet of TWS devices
• Can create a new network of devices or edit an existing one
• Can define circuits of a given line length by mapping a TWS line
module at one line end with another at the opposite line end
• Circuits can be two or three ended (that is containing one ‘tee’)
• Communication mode, ethernet or modem, and contact details
easily set for each device
• Link to TWS Base Station software to immediately start using new
configuration
Simple, fast method of setting up or editing a TWS network
without the need for specialist knowledge
TWS Installed Base
Approximately 1000 units have been sold to date to 70 Utilities in
30 Countries.
•
•
•
•
•
•
•
•
237 units in USA & Canada (23 Companies)
180 units in Africa (S. Africa, Namibia, Nigeria)
100 units in the UK
115 units in the Far East (Malaysia, HK, Indonesia, Vietnam)
100 units in Western Europe (France, Spain)
70 units in Australia & New Zealand
55 units in S. America (Brazil, Mexico, Argentina)
30 units in Scandinavia & Baltic countries.
Users by Type
•
•
•
•
•
•
•
Transmission greater than 100KV
Interconnected substations
Long lines greater than 100Km
Difficult terrain with access problems
Prone to bad weather – lightning, rain, gales
Poor maintenance record – more faults
Heavily loaded lines - line trips have bigger impact
New Generation Conductors
Transmission of Electric Energy
 Short History
&
 Development of Bare High
Voltage
Overhead Lines
(Bare OHC)
Important Conditions for Bare OHC
 Ampacity
 SAG
 Tension on the towers
 Tension in the conductor
 Temperature of the conductor
 Boundary conditions
History Bare OHC
 Since beginning all conductors
were made of
 Copper
or
 Copper Alloys
 Reasons:
 Good Conductivity
 Availability
Materials of Bare OHC
Material
Density
Conductivity
Tensile
Strength
CTE
g/cm3
% IACS
MPa
X 10 -6 / Co
Copper
8.9
100
450
17
Aluminium
2.7
61
165
23
Steel
7.8
9
1600
11.5
Alloy
2.7
52
325
23
Invar
7.1
14-23
1310 –
1170
3.7
AAC – All Aluminium Conductors
 Advantages:
Better Conductivity per unit of weight strung.
(Less tension on towers)
 Disadvantages:
Loses 60% of its strength when overloaded.
Has in absolute value less reserve in
strength to overcome wind and ice loading.
Continuous improvement in Bare OHC
ACSR
AAAC 6201
AL-59
TACSR
Good Conductivity –
53.0 % IACS*
Moderate
Better Conductivity – Moderate Conductivity
Conductivity – 52.5% 59% IACS*
– 52 % IACS*
IACS*
Moderate Corrosion
Resistance
Better
Corrosion Better
Resistance
Resistance
Corrosion Moderate
Resistance
Better Strength to Better Strength to
Weight Ratio
Weight Ratio
Good Strength to
Weight Ratio
Better
Strength
Moderate
Strength
Tensile Good Tensile Strength
Typical Application
Commonly used for
both transmission and
distribution circuits.
Typical Application
Transmission
and
Distribution applications
in
corrosive
environments,
ACSR
replacement.
Better Strength to
Weight Ratio
Tensile Better Tensile Strength
Typical Application
Transmission
and
Distribution High Ampacity
applications in corrosive
environments,
ACSR
replacement.
* International Annealed Copper Standard for conductivity
Corrosion
Typical Application
Transmission
and
Distribution High Ampacity
applications
in
noncorrosive
environments,
ACSR replacement.
An Overview of Bare
Overhead Transmission
Conductors
Categories of Overhead Conductors
Homogeneous Conductors
 AAC – All Aluminum Conductor
 AAAC – All Aluminum Alloy conductor
Non - Homogeneous Conductors
 ACSR
 ACSR/AW
– All Aluminum Conductor Steel Reinforced
– All Aluminum Conductor Al. Clad Steel
Reinforced
 TACSR
– Thermal Aluminum Conductor Steel Reinforced
 TACSR/AW – Thermal Aluminum Conductor Cl. Steel Reinforced
 TACIR/AW – Thermal Aluminum Conductor Cl. Invar Reinforced
 AACSR
– All Aluminum Alloy Conductor Steel
Reinforced
 ACAR
– All Aluminum Conductor Al. Alloy Reinforced
 ACSS
– All Aluminum Conductor Steel Supported
Limitations of Present Transmission System
 The present Transmission System is overloaded due to
Economic Expansion (Commercial, Industrial and
Residential)
 Max. Op. Temp with Existing ACSR Conductors 85 0C
 Very High cost to install new Transmission Lines.
 Very difficult to acquire Right of Way (ROW).
 Time constraint for new Transmission Lines.
 Objections from inhabitants to construct new T/L.
 Solution: New Generation Conductors ...
New Generation Conductors
Options Available with
Apar Industries Limited
High Ampacity Alloy Conductors
AAAC 6201,
6101
AAAC 1120
Defined as per IEC, Defined as per
ASTM, BS, NFC,
Australian
EN, CSA
Specification.
Specification.
Popularly in use
@ Countries:
France,
Bangladesh, India,
North and East
Africa, Middle East,
USA … so on
AL-57, AL-59
Thermal Resistant
Alloy (TAL)
Defined as per
Swedish
specification & EN
Specification.
Defined as per IEC, &
ASTM Specification.
Popularly in use @ Popularly in use @ Popularly in use @
Countries:
Countries:
Countries:
Australia & New
Norway, Sweden,
South and East Asia,
Zealand
India … so on
Nigeria, Middle East
Asia, Europe… so on
Up rating of Transmission System
Yes, New
No,
Transmission Lines
Re -Conductoring
High Ampacity Alloy
Conductors
Ground clearance is enough?
TAL with Al. Clad Invar
Core. i.e. for PGCIL ReConductoring Tender we
have offered TACIR/AW
388 sq mm against
ACSR Moose
Power T’xfer
Requirements
More
than
30%
Thermal Resistance Al.
Alloy Conductor
TACIR/AW &
TACIR/TW/AW,
GAP type
Conductors
TACSR, TACSR/EST,
TACSR/AW, TACSR/TW
Up to
30%
Al-59
AAA 1120
Summary
• TACSR family Conductor has 60+ % more ampacity of ACSR Conductors.
• TACSR/TW Conductor has more than 70+% more ampacity of conventional ACSR type.
• TACIR/TW Conductor has equivalent sag-tension properties as conventional ACSR type.
• Conventional fittings and accessories for ACSR can be used for TAL Conductors
except compression fittings
• Same installation method as conventional ACSR is applied for TALConductors
• TAL Conductors has high long-term reliability with strong track record
Use AL-59 & TACSR for New Lines and
TACIR/AW & GAP Conductor for Re-Conductoring
Greetings & Welcome
Presented by :
Workshop on latest
technologies on power
transmission sector: CBIP New
Delhi 20th MAY 2010
M N RAVINARAYAN
& N R DHAR
Dated on :
20-05-2010
Transmission line Signature Analysis.
- ECG OF TRANSMISSION LINES
- a necessity
1. Reduction of downtime
It is imperative on the part of Transmission line operator to
eliminate patrolling as far as practicable, reduce downtime, labour
and transportation cost . It is, therefore, necessary that accurate &
re-confirmed information is obtained before commencing
patrolling or sending team to the spot, on the instant information.
On-line fault locators today give data of instant information of
distance to faults with varying accuracy regarding location of fault
in a transmission line.
A reconfirmation with an Line Signature Analysis study is
preferable to accurately locate the prolonged presence of fault in
order to send teams to pinpointed fault location & repair the same
to reduce downtime.
2. Safe recharging of lines
Line Signature Analysis study prior to recharging, after the line
repair, reveals healthiness of line or indicates persistence of faults
in the event of a multiple fault condition. This will avoid stress
conditions on the terminal equipments, relays and eventual
line/system tripping, as the line can be declared faulty without
charging.
3. Predictive Maintenance
Line Signature study of a transmission line (Line healthiness study
or ECG of a transmission line) can predict developing fault
locations e.g. weak jumpers, leaky insulators etc on the line
indicating various degrees (immediate/2nd & 3rd preference etc) of
weakness of the line. Thus a planned maintenance schedule can be
programmed to avoid forced outage of any line. This helps in
reducing the downtime of the line to a greater extent.
4. Line pre-commissioning tests
Line Signature Analysis study is also most useful tool for precommissioning tests for a newly constructed Transmission Line.
Line Signature scans the entire line and provides documentation
on the line’s readiness for charging. Decision for charging a new
Transmission line can be taken based on this Line Signature study.
5. Accurate data independent of
operating parameters
The Signature Analysis does not require any presetting of line data,
no additional attachments interfering with the substation/power
station terminal equipments. The Line Signature Analysis study is
not influenced either by any effect due to dynamic behavior of the
transmission line that may be encountered when the transmission
line is in charged condition or by any data of line, conductors,
geometry of towers, GPS positioning etc. This is considered an
ideal situation for study of line condition.
6. Historical data for asset management
Line Signature Analysis provides historical data on the entire line,
its weakness/improvement, which can be useful for comparison
with subsequent data for monitoring the transmission line
condition at any given point of time for planning preventive
maintenance.
7. Data for Relay system
Feeding a correct data of a transmission line for on-line / Relay
system is essential. Length of a line constitutes an important factor
for input data of ONLINE / Relay system. The Signature Analysis
on application to a line provides accurate line length and hence
helps improve accurate functioning of on-line / Relay system.
8. A backup
Line Signature Analysis can be used as a back up of on-line
systems in the event of system failure. Various components are
responsible for measurement by on-line system whereas Line
Signature Analysis is an in-dependant system.
TAURUS EHT 1250 MAX-3
FAULT ANALYSER SYSTEM
UTILITY
1. Used for FAULT LOCATION
2. Used for Predictive Maintenance
3. Used for Pre–charging verification
4. Used for Pre-commissioning of EHT lines
The MAX-3 Digi Scan
-- Salient features..
1. Portable offline system with in-built re-chargeable battery.
Housed in IP67 pelican casing.
2. Complete fault Information in direct reading digital display
3. Complete Line Healthiness Study.
4. Can be used in any line EHT line from 66kV to 1250 kV.
5. Requires no parameter input. Extremely simple operation
6. Accuracy of +/- 100 meters through out the range of 1000 KM.
7. Direct PC storage and printout.
8. Optimum safety. Complete suppression of induction voltage
9. All the functionalities of the system can be tested with the EHT line Simulator.
10. Economical Investment – one single system is sufficient for the entire station and
applied to any EHT line from 66kV to 1250kV.
A look at
ECG OF TRANSMISSION LINES
- The LINE SIGNATURE ANALYSIS
GOOD LINE
NORMAL LINE
BAD LINE
GOOD LINE
NORMAL LINE
BAD LINE
A look at - All the in-homogeneous present on your EHV line
B PHASE OPEN :- PROGRESSIVE GAIN HIGHLIGHTS
06 4:43:15 PM :- 400 KV Mysore - Neelamangala ckt1
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135.8[3]
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135.8[8]
A3
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135.9[8]
A4
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012.3[1]
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026.1[1]
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135.9[8]
A5
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012.3[3]
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022.3[3]
026.2[3]
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036.0[1]
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050.7[1]
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060.3[1]
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086.3[1]
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118.7[1]
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135.8[8]
A6
002.0[8]
004.5[8]
012.2[6]
020.6[3]
022.2[5]
025.9[7]
029.3[3]
035.6[3]
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039.6[2]
046.4[3]
047.0[3]
050.5[3]
051.2[1]
056.6[3]
060.4[3]
065.9[3]
069.2[2]
078.7[2]
085.6[1]
086.3[3]
090.6[2]
096.7[3]
097.3[3]
102.6[2]
112.7[1]
118.7[4]
124.0[1]
126.6[1]
135.8[8]
Remarks
X
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E
Case Studies
Decapping FAULT AT 69 KM IN B PHASE
DECAPPING FAULT
SHORT CIRCUIT FAULT AT 112 KM IN Y PHASE
SHORT CIRCUIT
FAULT
Thank you