From economical point of view designing of transmission line system is very important in the electricity supply system. Extra High Voltage Transmission Lines are best suited for transmission of bulk power.

1. SIMULATION OF EXTRA HIGH
VOLTAGE LONG AC TRANSMISSION
LINE
PRESENTED BY:
SHIVANGEE
KAMINI SINGH
KUMARI PRIYANKA
GUIDED BY:
MS. SHIKHA CHOUDHARY
(Assistant Professor)
DEPARTMENT OF ELECTRICAL ENGINEENIRING
RAJKIYA ENGINEERING COLLEGE
AMBEDKARNAGAR

2. CONTENTS
• INTRODUCTION
• NEED
• COMPONENTS
• DESIGN METHODOLOGY
• ELECTRICAL REQUIREMENT
• SELECTION OF TRANSMISSION VOLTAGE
• SELECTION OF TOWER STRUCTURE
• SELECTION OF CONDUCTOR SIZE
• INSULATOR REQUIREMENT

3. • ADVANTAGES
• DISADVANTAGES
• APPLICATIONS
• MATLAB
• SIMULATION CIRCUIT
• BLOCKS USED IN SIMULINK MODEL
• RESULTS
• CONCLUSION
• REFERENCE

4. INTRODUCTION
Electrical power system has three principle divisions :
▫ Generating station
▫ Transmission system
▫ Distribution system

6. • In electric power transmission engineering this
refers to equipment designed for more than
345,000 volts between conductors.
• Two factors considered in the classification of
a “high voltage” are the possibility of causing
spark in the air and danger of electric shock by
contact.

7. VOLTAGE RANGE
• Extra low voltage – below 70 V
• Low voltage – upto 1000V
• Medium Voltage – 1000V to 35 kV
• High Voltage – 35 kV to 230 kV
• Extra high voltage – above 230 kV
• Ultra high voltage – above 800 kV

8. TRANSMISSION PLANNING
• Data evaluation.
• Technical evaluation.
• Economic evaluation.
• Environmental impact assessment.

9. NEED
• Increase transmission efficiency.
• Decrease volume of the conductor.
• Increase transmission capacity.
• Economical to interconnect the power system on a
large scale.
• No. of circuit and the land requirement decreases.

10. COMPONENT
• Conductor
• Earth wire
• Insulator
• Transmission tower

12. DESIGN METHODOLOGY
• Collecting preliminary line design data and gathering
available climatic data.
• Calculating climatic loading on components.
• Calculating loads according to safety requirements.
• Selecting appropriate correction factors.
• Designing the components for the above load and
strengths.

13. ELECTRICAL REQUIREMENT
• Continuous current rating.
• Short time current rating.
• Voltage drop.
• Power loss.
• Diameter of conductor.
• Length of line.

14. SELECTION OF TRANSMISSION VOLTAGE
• Standard voltage – 66,110,132,220,400 KV
Selection criterion of Economic Voltage
• Length of line
• Voltage regulation
• Power loss in transmission
• Initial and operating cost

15. ECONOMIC VOLTAGE OF TRANSMISSION OF POWER
• E = 5.5 √(L(km)/1.61+(load in kva)/150)
Table: Economic Voltage of Transmission of Power
Power Transfer
Requirement
(MW)
Distance
(km)
Economic Voltage
Level
(KV)
3500 500 765
500 400 400
120 150 220
80 50 132

16. SELECTION OF TOWER STRUCTURE
• Single circuit tower/Double circuit tower.
• Length of insulator assembly.
• Minimum clearances between conductors, and
between conductors and ground.
• Location of ground wires with respect to outermost
conductor.
• Minimum clearance of the lowest conductor above
ground level.

17. HEIGHT OF TOWER STRUCTURE
Height of tower is determine by
H=h1+h2+h3+h4
h1=ground clearance
h2=sag
h3=vertical spacing between conductors
h4=vertical clearance between earth wire
and top conductor

18. SELECTION OF CONDUCTOR SIZE
1. Mechanical Requirement
• Tensile strength(for tension)
• Strain strength(for vibration)
2. Electrical Requirement
• Continuous current rating
• Short time current carrying rating
• Voltage drop
• Power loss
• Length of line
• Charging current

19. INSULATOR REQUIREMENT
• Toughened glass
• Fiber glass
• High grade electric porcelain
Types of insulators are categorized as :
• Pin type
• String type
1. Suspension type
2. Strain type

20. ADVANTAGES
• Reduction of electrical losses.
• Increase in transmission efficiency.
• Improvement of voltage regulation.
• Reduction in conductor material.
• Flexibility for future system growth.
• Increase in transmission capacity.

21. DISADVANTAGES
• Corona loss and radio interference.
• Line supports.
• Erection difficulties.
• Insulation needs.
• High cost.
• Generates electrostatic effects which are harmful to
human being & animals.

22. APPLICATION
• In electrical power distribution.
• In cathode ray tubes, to generate X-rays and
particle beams, to demonstration arcing for
ignition.
• In photomultiplier tube
• Industrial and scientific application.

23. MATLAB
• MATLAB (Matrix Laboratory) is a tool for numerical
computation and visualization.
• Simulink is a block diagram environment for multi
domain simulation and Model-based design.
• In MATLAB simulation the same model or topology can
be tested with the real time hardware ratings and device
specifications.

24. • The applications of this software are really prove
their worth through their real time applications.
• It supports system-level design, simulation, automatic
code generation and continuous test and verification
of the system.

25. SIMULATION CIRCUIT
• The implementation of any converter circuit
needs to be tested before going for hardware.
• The applications of this software are really
prove their worth through their real time
applications.
• The objective of this minor project is to analyze
and design Extra High Voltage Long AC
Transmission Line .

26. • Simulink model of Design of Extra High Voltage Long
AC Transmission Line is shown in figure1.
• The results obtained after simulation are used in the
designing of Extra High Voltage Long AC Transmission
Line Model.

27. Figure 1: Simulink Model

28. BLOCKS USED IN SIMULINK MODEL
• Discrete Measurement: It allows to solve the circuit
discretization of the electrical system for a solution at
fixed time steps.
• Constant: The Constant block generates a real or
complex constant value.
• Three Phase RLC load: It implements three balanced
branches consisting each of a resistor, an inductor, or a
capacitor or a series combination of these.

29. • Three-phase transformer: This block
implements a three-phase transformer using three
single-phase transformers.
• Circuit Breaker: It uses signal and phase current
information to break an electrical circuit.
• Transmission Line: This block implements a
balanced three-phase transmission line model with
parameters lumped in a PI section.

30. •Series Compensated Network: In order to
increase the transmission capacity, each line is
series compensated.
•Three Phase Synchronous generator: The
Simplified Synchronous Machine block models
both the electrical and mechanical characteristics
of a simple synchronous machine.
•Three phase Source: This block implements a
balanced three-phase voltage source with an
internal R-L impedance.

31. • Three Phase VI Measurement: This block is
used to measure instantaneous three phase
voltages and currents in a circuit.
•Bus Selector: This block outputs a specified
subset of the elements of the bus at its input.
•Scope: This block displays time domain signals
with respect to simulation time.

32. RESULTS
Fig 1.1: Voltage and Current waveform at generation side

33. Fig 1.2: Voltage and Current waveform at load side

34. CONCLUSION
• From economical point of view designing of transmission
line system is very important in the electricity supply system.
• Extra High Voltage Transmission Lines are best suited for
transmission of bulk power.
• It helps to investigate system functionality, performance and
to verify overall design.

35. • The result is a reduction in development time and cost,
increased system reliability and performance
optimization.
• From this work and result analysis the designing of
Extra High Voltage AC Transmission Lines is
efficiently observed .

36. REFERENCE
• www.google.co.in
• www.wikipedia.org
• www.slideshare.net
• www.ijsret.org
• www.newacademicscience.co.uk
• www.electricaltechnology.org
• http://eeexplore.ieee.org