This slide contains
1. Introduction of Overhead and Underground Cables
2. Main Components of Overhead Lines
3. Propertis of Conductor Materials
4. Commonly Used Conductor Materials
5. Line Supports
6. Different types of Line Support with properties
7. Insulator and its properties
8. Types of Insulator
9. Transmission Line Challenges in Nepal
Since the loads having the trends towards growing density. This requires the better appearance, rugged construction, greater service reliability and increased safety. An underground cable essentially consists of one or more conductors covered with suitable insulation and surrounded by a protecting cover. The interference from external disturbances like storms, lightening, ice, trees etc. should be reduced to achieve trouble free service. The cables may be buried directly in the ground, or may be installed in ducts buried in the ground.
UNIT - 05 DISTRIBUTION LINES AND TRANSFORMER CENTREPremanandDesai
Code of practice for Distribution Lines and Transformer centre, types of transformer centres -
Pole mounted, plinth mounted, indoor and outdoor types. Determining the rating of
Distribution Transformer. Write Specifications of the Distribution Transformer. Draw the
SLD of a Transformer centre indicating the size of protective devices, Prepare the schedule of
equipments /Materials with specifications for a 11KV/415V,100 KVA transformer centre and
their estimates, 415 V LT line materials and specifications , method of calculating various LT
line materials (only). Prepare the schedule of materials (only) for 3 phase 4 wire LT line,
11 KV HT Line-materials and their specifications, method of calculating various HT line
materials and tapping structure, TOPO sheet and its use, Concept of combined estimates.
Prepare the schedule of materials (only) for 11 KV single circuit HT line for Rural
Electrification.
(Note: HT lines over head type only)
Since the loads having the trends towards growing density. This requires the better appearance, rugged construction, greater service reliability and increased safety. An underground cable essentially consists of one or more conductors covered with suitable insulation and surrounded by a protecting cover. The interference from external disturbances like storms, lightening, ice, trees etc. should be reduced to achieve trouble free service. The cables may be buried directly in the ground, or may be installed in ducts buried in the ground.
UNIT - 05 DISTRIBUTION LINES AND TRANSFORMER CENTREPremanandDesai
Code of practice for Distribution Lines and Transformer centre, types of transformer centres -
Pole mounted, plinth mounted, indoor and outdoor types. Determining the rating of
Distribution Transformer. Write Specifications of the Distribution Transformer. Draw the
SLD of a Transformer centre indicating the size of protective devices, Prepare the schedule of
equipments /Materials with specifications for a 11KV/415V,100 KVA transformer centre and
their estimates, 415 V LT line materials and specifications , method of calculating various LT
line materials (only). Prepare the schedule of materials (only) for 3 phase 4 wire LT line,
11 KV HT Line-materials and their specifications, method of calculating various HT line
materials and tapping structure, TOPO sheet and its use, Concept of combined estimates.
Prepare the schedule of materials (only) for 11 KV single circuit HT line for Rural
Electrification.
(Note: HT lines over head type only)
This presentation is from my talk Delivered to Young Engineers to have a brief overview of :
1. Substation And Its Types
2. Substation Equipment
3. Substation Grounding
4. Design Consideration
5. Bus Switching Scheme
6. Basic Insulation Level and Its importance
7. Fault level and its importance
8. Other Equipment
9. Substation IEC 61850 Protocol Basic
It will be helpful for Engineering students to have an overview from a Practical point of view. Widely publicize it for benefit of others.
HVDC (high-voltage direct current) is a highly efficient alternative for transmitting large amounts of electricity over long distances and for special purpose applications.
This presentation is from my talk Delivered to Young Engineers to have a brief overview of :
1. Substation And Its Types
2. Substation Equipment
3. Substation Grounding
4. Design Consideration
5. Bus Switching Scheme
6. Basic Insulation Level and Its importance
7. Fault level and its importance
8. Other Equipment
9. Substation IEC 61850 Protocol Basic
It will be helpful for Engineering students to have an overview from a Practical point of view. Widely publicize it for benefit of others.
HVDC (high-voltage direct current) is a highly efficient alternative for transmitting large amounts of electricity over long distances and for special purpose applications.
This is the simple ppt explaining about the main components of the power systems. especially we are determining the insulators and its types with real time pictures which are attractive,
Transmission and distribution line design finalBhanu Poudyal
Transmission Line designed on basis of data available for a given Hydropower system.
Looking this document you can yourself design the Transmission Line system.
Complete details of EHV Transmission Line. Consolidated this presentation from those experts who had contributed separately on slider share and other web pages.Thanks for their valuable inputs.
The following topics will be covered: the definition of a substation, an overview of the different type of substations and the functions of substations
Nepal’s access to energy and modern energy services is inadequate and the use of energy is inefficient. The electrical power supply is characterized by scheduled power interruption up to 16 hours daily. The insufficient and interrupted supply of electricity affects industrial production negatively and forces more and more industrial and commercial enterprises to generate their own electricity generally by means of diesel generators. Over the last year its development has led to the increased import of petroleum products contributing to an increased trade balance deficit. Furthermore, the additional burning of fossil fuels results in higher emissions of climate change relevant and environmentally harmful pollutants.
Energy efficiency improvements help industries, business, governments, and consumers meet their needs by using less energy, saving them money, driving investment across all sectors of the economy, creating much needed jobs, and reducing the myriad of environmental impacts of the energy production system. The industrialists, regulators, and citizens are increasingly recognizing the energy efficiency is a crucially important national resource. In fact, the demand for the energy efficiency audit by the industrialists in Rupandehi is increasing day by day.
After performing the energy efficiency audits in the industries as well as the business, the project has identified the saving potential of around 2,000 kVA electrical demand, 3,39,000 kWh electricity, 33,380 litres of Diesel fuel, 27,300 litres of Furnace Oil and 31,14,000 MJ of thermal energy.
Electricity and each type of fuel savings are being compared with the annual electricity sales by Nepal Electricity Authority (NEA) and fuel sales by Nepal Oil Corporation (NOC). Practice of energy efficiency in the different sectors has proved the saving of electrical energy equivalent to 4.03% of the sales by NEA and 2.39% of diesel sales by NOC. Finally, the energy efficiency project is being adopted by the industrialists and the business personnel to enhance their energy use.
This is the summary to choose main components of Mechanical design of Overhead T/L .
For more contacts: ranjeetkumar13el42@gmail.com
@Fb : fb/ranjeet.ray.42
Seismic response of transmission tower a case studyeSAT Journals
Abstract Towers and tower like structures are the major infrastructure for the transmission of electrical power, telecommunication and broadcasting. The transmission towers are highly repetitive and therefore the analysis and designs should be highly competitive towards commercial solutions. In the present study, an attempt has been made to analyse the existing Electrical Transmission tower of voltage 220kV using FEM software NISA. The analysis of an existing structure without secondary bracings has been carried out for the North-South Component of EL-Centro Ground motion, 1940.In this analysis, the stiffness and damping properties have been considered for improving the seismic performance of the existing structure. By keeping the Group number as it is, using different sections, the geometric properties of the given angle section are optimized to optimized angle section and optimized tubular section. For cross braces, the damping value is varied ranging from 5%-25% for above sections. In this analysis, the displacement at top cross-arm of the tower is considered as the main parameter for conservative results. Finally the results obtained are regarding possible improvements in the analysis of the existing structure
Micro-alloyed copper overhead line conductors - Wire & Cable Technology Inter...Leonardo ENERGY
http://www.bluetoad.com/publication/?i=217299&p=90
Overhead line conductors are traditionally a domain for aluminium, using either steel reinforced aluminium or aluminium alloys. Using copper for overhead lines might surprise some people because it is a substantially heavier material. Weight, however, is not the most crucial characteristic of the conductor. Its smaller section and hydrophobic coating reduces the wind and ice loads on the conductors, which makes the overhead line more resistant and resilient to weather conditions.
Also, the higher conductivity of copper reduces the losses and the life cycle cost of the overhead line.
Micro-alloyed copper overhead line conductors - PowerGrid International Augus...Leonardo ENERGY
http://www.elp.com/articles/powergrid_international/print/volume-19/issue-8/features/microalloyed-copper-overhead-line-conductors.html
Overhead line conductors are traditionally a domain for aluminium, using either steel reinforced aluminium or aluminium alloys. Using copper for overhead lines might surprise some people because it is a substantially heavier material. Weight, however, is not the most crucial characteristic of the conductor. Its smaller section and hydrophobic coating reduces the wind and ice loads on the conductors, which makes the overhead line more resistant and resilient to weather conditions.
Also, the higher conductivity of copper reduces the losses and the life cycle cost of the overhead line.
New generation of copper conductors for overhead linesLeonardo ENERGY
Transmission network operators are facing substantial and even contradictory challenges. A highly variable renewable energy supply and an increased focus on energy efficiency require a reinforcement of the grid, but the resistance against the construction of new lines has never been so high. The new generation of copper alloy conductors can be part of the solution.
These copper alloys offer outstanding mechanical properties and a high annealing temperature that makes possible to apply affordable and durable hydrophobic coatings. This unique combination makes the new copper conductors highly suitable for severe weather conditions (wind & cold) both in new lines and in refurbishment projects. Additionally, the high conductivity of copper offers a significant reduction of life cycle costs.
This webinar will present the main properties of the new copper alloy conductors and how they allow to respond to the transmission and distribution network new challenges. Also a concrete case study for a 70 km line will be presented, stressing the relevance of the cost of losses and minimizing the total cost of ownership.
New generation of copper conductors for overhead linesLeonardo ENERGY
Transmission network operators are facing substantial and even contradictory challenges. A highly variable renewable energy supply and an increased focus on energy efficiency require a reinforcement of the grid, but the resistance against the construction of new lines has never been so high. The new generation of copper alloy conductors can be part of the solution.
These copper alloys offer outstanding mechanical properties and a high annealing temperature that makes possible to apply affordable and durable hydrophobic coatings. This unique combination makes the new copper conductors highly suitable for severe weather conditions (wind & cold) both in new lines and in refurbishment projects. Additionally, the high conductivity of copper offers a significant reduction of life cycle costs.
This webinar will present the main properties of the new copper alloy conductors and how they allow to respond to the transmission and distribution network new challenges. Also a concrete case study for a 70 km line will be presented, stressing the relevance of the cost of losses and minimizing the total cost of ownership.
Conductor materials - Copper and its alternativesLeonardo ENERGY
The only known electrical conductor materials with a commercial applicability are copper and aluminium. Between these two there is only limited competition because their other characteristics beyond electrical conductivity are so different. Which are these differences, and are there any other materials that may serve as electrical conductors? How about competing technologies such as wireless energy transfer?
Copper alloy conductors for overhead lines - CIGRÉ Regional South-East Europe...Leonardo ENERGY
Transmission network operators are facing substantial and often contradictory challenges. A highly variable renewable energy supply and an increased focus on energy efficiency require the reinforcement of the grid. However, resistance to the construction of new lines is huge. Micro-alloyed copper conductors can be part of the solution. Their energy efficiency and their ability to cope with temporary capacity overloads are highly valued features. Such overloads are possible due to the higher resistance of copper against creep at high temperatures. The energy efficiency of the copper conductor compensates for its higher initial cost. As a result, its life cycle cost (LCC) is often lower than that of a steel reinforced aluminium (ACSR) conductor. This was the finding of two feasibility studies conducted by DNV GL (KEMA). The first study examined the construction of new lines; the second investigated the refurbishment of existing lines. The latter study also demonstrated why the higher specific weight of copper compared to an ACSR conductor does not require any reinforcement of the overhead line towers. The smaller cross section combined with a hydrophobic coating results in a much lower wind and ice load, which is a decisive factor for determining the required strength of the towers. This makes the copper conductor particularly suitable in cold and windy climates.
CIGRÉ Regional South-East European Conference
Cathodic prevention of steel rebars in concrete the international outlookSimone Tremolada
The fundamental application of " cathodic prevention " of steel reinforcement in concrete was ideated and developed by Professor Pietro Pedeferri. It was successfully applied since 1989 in Italy on Viaduct St. Nicholas I of the highway Rome - Aquila - Teramo and in 1996 in the western underbroadwalk of the Sydney Opera House. Over the past 20 years it has spread throughout the world and particularly in Northern Europe, Middle East and Australia being recognized as the most reliable technique to combat corrosion for new buildings and infrastructure where reinforced concrete is exposed to possible contamination from chlorides. This memory is a review of some of the most significant industrial cases reported in the international literature.
Durrat Al Bahrain and the NAKILAT shipyard in Qatar are two recent projects developed in the Middle East. Cathodic Prevention of West Swanson Dock in Melbourne was the largest project completed in Australia in the last decade.
Other significant experiences in China and North Africa are a sign of the vitality of this technique in the developing countries.
Copper alloy conductors for overhead lines - Nordic Conference on Electricity...Leonardo ENERGY
New generation of micro-alloyed copper conductors to face DSOs challenges
Distribution network operators are facing substantial and often contradictory challenges. A highly variable renewable energy supply and an increased focus on energy efficiency require the reinforcement of the grid. However, resistance to the construction of new lines has never been higher. Micro-alloyed copper conductors can be part of the solution. Their energy efficiency and their ability to cope with temporary capacity overloads are highly valued features. Such overloads are possible due to the higher resistance of copper against creep at high temperatures. The energy efficiency of the copper conductor compensates for its higher initial cost. As a result, the life cycle cost (LCC) of the micro-alloyed copper conductor is in the same range or lower than that of a steel reinforced aluminium (ACSR) conductor. This was the finding of two feasibility studies conducted by DNV GL (KEMA). The first study examined the construction of new lines; the second investigated the refurbishment of existing lines. The latter study also demonstrated why the higher specific weight of copper compared to an ACSR conductor does not require any reinforcement of the overhead line towers. Indeed, copper’s mechanical strength makes a steel core superfluous and even more importantly, the smaller cross section combined with a hydrophobic coating, results in a much lower wind and ice load, which is a decisive factor for determining the required strength of the towers. This makes the copper conductor particularly suitable for overhead lines in cold and windy climates.
NORDAC 2014
Eleventh Nordic Conference on Electricity Distribution System
Management and Development.
Stockholm, 8 - 9 September 2014
Busbars, busducts, and busways using copper conductors have several advantages compared to their counterparts fabricated from other materials.
The main advantages of copper arise from its high electric conductivity (low electric resistance). These characteristics make it possible to create busways with the same current carrying capacity but that are smaller and/or more energy efficient.
In addition, the use of copper results in highly durable connections that can resist strong mechanical forces.
Cost of the conductor should not be the only consideration when evaluating the cost of a busway. The cost of the mechanical support systems, the energy losses over the lifetime of the installation, and the scrap value of the material at its end-of-life must all be taken into consideration in order to gain an accurate picture. When this is done, it becomes clear that the initial price of copper has only a minor influence on the total life cycle cost of the busway.
A complete slide to teach you about basics of electrical power transmission with a lot of images. Including basic definition, one-line diagram, economy, various types of conductors, towers, poles, insulators and problems regarding transmission system. It also includes questions and discussions to clear the concept. Whole slides is written in point form, so you can catch the main concept about transmission system easily
Similar to Mechanical Design of Transmission Line (In context of Nepal) (20)
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Planning Of Procurement o different goods and services
Mechanical Design of Transmission Line (In context of Nepal)
1. Mechanical Design Of Transmission Line
(In context of Nepal)
PRESENTED BY
SHULAB SHRESTHA
Third Year
17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 1
2. Introduction:
WHY OVERHEAD LINES???
17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 2
ELECTRICAL CONSIDERATIONS FOR TRANSMISSION LINE DESIGN:
LOW VOLTAGE DROP
MINIMUM POWER LOSS FOR HIGH EFFICIENCY OF POWER
TRANSMISSION.
THE LINE SHOULD HAVE SUFFICIENT CURRENT CARRYING CAPACITY SO
THAT THE POWER CAN BE TRANSMITTED WITHOUT EXCESSIVE VOLTAGE
DROP OR OVERHEATING.
3. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 3
The underground cables are rarely used for power transmission due to two main
reasons.
installation costs for underground transmission will be very heavy.
proper insulation to the cables to withstand higher pressures.
Why Not UNDERGROUND CABLES???
Therefore, it has limited use for
distribution in congested areas where
safety and good appearances are the
main considerations.
4. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 4
Main Components of Overhead Lines
1. Conductors
2. Supports: Towers, Poles
3. Insulators: attached to supports and insulate the conductors from the ground.
4. Cross arms: support to the insulators and conductor
5. Guys and Stays: cables fastened to the poles to support the poles
6. Lightening arresters: to discharge excess voltage due to lightening to earth
7. Fuses and Isolation Switches: to isolate different parts of the overhead system
8. Guard Wires: above or below power lines while crowing telephone line to prevent
electromagnetic interference
9. Miscellaneous items: Phase Plate, Danger Plate, Barbed Wire, Vibration Dampers
5. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 5
Main Components of Overhead Lines
6. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 6
Main Components of Overhead Lines
GUYS AND STAYS
FUSE
BIRD
GUARDS
GUARD
WIRE
LIGHTENING
ARRESTORS
7. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 7
CONDUCTOR MATERIALS
• High Electrical Conductivity
• High Tensile Strength
• Low Cost
• Low Specific Gravity
• Easy Availability
• Not so brittle
8. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 8
COMMONLY USED CONDUCTOR MATERIALS
• Copper
• Aluminum
• Steel-Cored Aluminum
• Galvanized Steel
• Cadmium Copper
9. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 9
COPPER
• High Electrical Conductivity
Low resistance = 16.78 nΩ•m at 20 °C
High Current Density
• Greater Tensile Strength
• Small Cross Section Area
Low wind resistance → less transverse load in tower
• Expensive
• Durable, high scrap value
• Scarcity
10. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 10
ALUMINUM
• Cheap and light compare to copper
• Less electrical conductivity and tensile strength
Conductance = 60% that of copper for same cross section
For same resistance areaAl = 1.26 areaCu
• Specific gravity of aluminum is less than copper.
Less weight on supports
generate greater swings hence large cross arms required
• Low melting point → cannot withstand short-circuit currents
• Used for low voltage distribution lines
11. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 11
STEEL CORED ALUMINUM
ASCR(Aluminum Conductor Steel Reinforced)
• Core of galvanized steel, aluminum conductors it outer layers
• Cross section ratio steel : Al is 1:6 (1:4 for high tensile strength)
• Increase tensile strength
less sag
greater span
lesser tower height
• Universally used in transmission and
distribution
12. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 12
GALVANIZED STEEL
• High tensile strength → greater span
• Low conductivity → greater cross sectional area
• Eddy current and hysteresis loss
• Used in small power, small distance system where required cross
section is very low for ACSR or Copper
13. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 13
CADMIUM COPPER
• Cadmium and Copper alloy
• 1-2% cadmium is added to copper → increase tensile strength by 50%
• Long span is possible
• Expensive
• Used in small power where cross section required is small
14. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 14
SUPPORTS
Line supports should have following properties:
i. High mechanical strength to withstand the weight of conductors and
wind loads
ii. Light in weight
iii. Economical in cost and maintenance
iv. Longer life
v. Easy accessibility for conductors and insulators for maintenance
15. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 15
TYPES OF LINE SUPPORTS
1. Wooden Poles
Cannot be used for high voltage > 20 KV
Less mechanical strength
Short life time 20-25 years
16. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 16
TYPES OF LINE SUPPORTS
2. Steel Poles
Greater mechanical strength
Longer life 40 years
Longer spans 50-80 m
Lighter in weight
17. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 17
TYPES OF LINE SUPPORTS
3. RCC Poles
Reinforced Cement Concrete
Greater mechanical strength
Longer life than steel poles
Longer spans 80-200 m
Used for up to 33 KV
Good insulating
18. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 18
TYPES OF LINE SUPPORTS
4. Steel Tower
Assembly of galvanized angle sections
Used for long distance transmission and high voltage (>66 KV)
Greater mechanical strength, longer life, longer spans than RCC or
steel poles
High tower → lightening hazard → tower footing grounded to
bypass lightening
19. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 19
TYPES OF LINE SUPPORTS
220 KV double circuit
transmission tower
220 KV single circuit
transmission tower
110 KV single circuit
transmission tower
20. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 20
IN CONTEXT OF NEPAL
Pre stressed concrete (PSC) Poles
22. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 22
INSULATOR
Line conductors should be insulated from support system
to prevent leakage to ground
To prevent potential hazard due to the leakage
Insulation required depends upon voltage level
Materials: porcelain, glass, rubber
In Nepal Porcelain insulator is largely used
23. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 23
INSULATOR
The insulators should have the following desirable properties :
1. High mechanical strength
2. High electrical resistance
3. High relative permittivity of insulator material in order that dielectric
strength is high.
4. High ratio of puncture strength to flashover.
5. Economical in cost and maintenance.
24. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 24
TYPES OF INSULATOR
Pin Type Suspension Type Strain Type
Shackle Stay
25. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 25
TRANSMISSION LINE CHALLENGES IN NEPAL
There is no access to power for the approx. 58 percent of population.
NEA has the monopoly in electricity.
Over the period of 100 years, Nepal has built just 981 KM circuit of transmission line
which clearly shows NEA has rarely shown any interest in the transmission line
According to 20 year power generation report :- If Nepal’s economy had a capacity to
absorb 11500 MW (peak hour), it would have required 845 KM long 400 KV lines, the
total cost for which would have been Rs 41 billion and for 612 north south 400 KV
would required Rs 33 billion and for 612 north south 400 KV would require Rs 33
billion.
If Nepal builds this transmission line, there will be a rush of investors to invest in
Nepal. In case, India agrees, even Nepal will be able to export its power to Bangladesh.
26. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 26
TRANSMISSION LINE CHALLENGES IN NEPAL
NEA is planning to expand its transmission line to 3272 KM or circuit. This includes 78 kilometers of 33 KV,
1409 kilometers of 132 KV, 755 KM of 200 KV and 1030 KM of 400 KV in the coming ten years.
to complete this project NEA needs huge amount of investment and manpower (technicians).
The corridor transmission line projects include Kabeli Damak 132, Kosi corridor (Bashantapur-Kusha) 220
KV, Katari-Okhaldhunga, Solu, Singati-Lamosanghu,Sunkosi-Dolkha,Ramecchap –Garjyan-Khimti, Middle
Marsyangdi-Manang, Kaligandaki 220 KV, Katari-Okhaldhunga-Solu, Singati-Lamosanghu, Sunkosi-Dolkha,
Ramecchap-Garjyan-Khimit, Middle Marsyangdi-Manang, Karnali Corridor (Lamki-Upper Karnali)132 KV.
Under the absorption project are Thanko-Chapagaun-Bhaktapur, 132 KV, Syangja132 substation, Kamane
Substation, Kushum-Hapure 132 KV transmission line, Butwal-Kohalpur, Chapali 132, Matatirtha 132 kv
station. Similarly, the primary phase of project include Bajhang-Dipayal-Attariya Transmission line, Hapure-
Tulsipur Transmission line Surkhet-Dailekh-Jumla Transmission like, Kaligandai-Gulmi (Jhimruk)132 kv
Transmission line, Hetauda Butwal 400 KV Transmission line, Butwal-Lamki 400 KV Transmission line and
Lamki- Mahendranagar 400 KV Transmission line.
27. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 27
TRANSMISSION LINE CHALLENGES IN NEPAL
Out of all those corridor transmission project NEA has completed just 2 projects.
Hetauda-Kamane 132/33kV Substation Matatirtha Substation Expansion work
28. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 28
TRANSMISSION LINE CHALLENGES IN NEPAL
Without construction of transmission lines, one cannot expect any private investment
and even NEA cannot build any project.
The government has no plans to construct the transmission line in the attractive power
generation sites like road.
Land acquisition is one of the major challenges for the construction of transmission line.
Construction of transmission line is matter of major debate and controversy.
Even the government agrees to construct the transmission line; it has to face several
hurdles at the implementation stage from the people.
For instance, the second circuit of Heatuda Dhalkebar 132 KV Transmission line took a
decade to complete. Thankot, Chapagaun and Bhaktapur (132 KV) Transmission line
project was canceled due to opposition from people.
29. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 29
TRANSMISSION LINE CHALLENGES IN NEPAL
Private investment company shows
hesitation in investment mainly for
one reasons lack of commitment on
the construction of transmission line
NEA Annual Report 2014
30. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 30
TRANSMISSION LINE CHALLENGES IN NEPAL
Nepal-India Transmission line has another painful story to tell.
Whether to import power from India or to export, Nepal needs grid connection with
India. With the fund available from the World Bank, Nepal-India agreed to complete the
Dhalkebar- Mujafarpur 400 KV transmission line by 2014. However, no progress has
been made yet on the project.
The annual peak power demand of the Integrated Nepal Power System (INPS) in fiscal
year 2013/14 is estimated to be 1,201 MW, Compared to the preceding fiscal year’s
figure of 1,094.6 MW, the annual peak power demand of the INPS registered a
growth rate of 9.7 %.
31. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 31
TRANSMISSION LINE CHALLENGES IN NEPAL
32. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 32
TRANSMISSION LINE CHALLENGES IN NEPAL
The dream to end the immediate load shedding of Nepal by importing electricity
through this grid seems to be just a dream.
In conclusion, if NEA and government does not give grid development project the
upmost priority, Nepal seems to fail in development in Hydropower.
33. 17 October 2016DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING 33
REFRENCES
http://www.slideshare.net/Dhananjayjha2043/electrical-transmission-
line?related=2
http://www.conceptohub.com/lesson/mechanical-design-of-overhead-
transmission/
http://www.slideshare.net/search/slideshow?searchfrom=header&q=CONDUCTOR
https://en.wikipedia.org/wiki/Transmission_tower
http://www.tpub.com/neets/book4/11e.htm
file:///C:/Users/Sulav/Downloads/Transmission%20Line%20Challenges%20_%20Ne
wSpotLight%20Nepal%20News%20Magazine.htm
http://www.bnmahtogroup.com/industry_register/nepal-poles-industries-pvt-ltd/
http://www.nea.org.np/anual-report.html
Book : Principle of power System V.K. Mehta