2. What is wind turbine/wind mill
Wind turbine is a device that converts kinetic energy into
mechanical energy
If the mechanical energy is used to produce electricity, the
device may be called a wind turbine
If the mechanical energy is used to drive machinery, such as
for grinding grain the device is called a
wind mill.
4. Why Did we take this project
of wind turbine?
IT’S VERY CHEAP.
WIND POWER CONSUMES NO FUEL. SO IT IS VERY RELIABLE.
MORE EFFICIENT.
SUITABLE FOR KARACHI CLIMATE.
COMPARED TO THE ENVIRONMENTAL IMPACT OF
TRADITIONAL ENERGY SOURCES, THE ENVIRONMENTAL
IMPACT OF WIND POWER IS RELATIVELY MINOR IN TERMS OF
POLLUTION.
WIND TURBINES CAN CARRY ON GENERATING ELECTRICITY
FOR 20-25 YEARS. OVER THEIR LIFETIME THEY WILL BE
RUNNING CONTINUOUSLY FOR AS MUCH AS 120,000 HOURS
6. 1. DC Motor
A DC MOTOR IS A MACHINE WHICH CONVERTS ELECTRICAL
ENERGY INTO MECHANICAL ENERGY.
7. Construction of DC motor
DC MOTOR CONSISTS OF THE FOUR IMPORTANT PARTS.
ARMATURE: A RECTANGULAR COIL WHICH IS MADE OF
INSULATED COPPER WIRE WHICH IS WOUND ON THE SOFT IRON
CORE THIS IS ARMATURE.
FIELD WINDING: THE FIELD WINDINGS ARE ATTACHED TO
INSIDE OF THE YOKE AND TO FORM TWO POLES FITTING
CLOSELY TO THE ARMATURE.
COMMUTATER AND BRUSHES: COMMOTATOR IS USED TO
REVERSE THE DIRECTION OF CURRENT. PRESS SLIGHTLY AGAINST
THE TWO SPLIT RINGS AND THE SPLIT RING ROTATE BETWEEN THE
BRUSHES. THE CARBON BRUSHES CONNECTED TO THE DC
SUPPLY.
8. Internal structure:
THE YOKE (OR CASING): IT COVERS THE WHOLE MACHINE
AND PROVIDES THE MECHANICAL SUPPORT TO THE POLES
9. WORKING PRINCIPLE OF DC MOTOR
when A current coil conductor is placed inside of the
magnet field .when the current is passed through the
conductor a field is produced around it. And the
direction of this magnetic field can be determined by
the right hand rule .because of the current flows
through the segments of the loop is in different
direction it means that that are opposite to each
other as shown in the figure .The segment on one side
pushes the upward while the segment on the other
side pushes the down word. it mean that both sides of
the armature experience the force which is in equal in
magnitude but in opposite in direction and its known
as couples forces these combined forces create the
twisting action or torque.
10. The direction of Forces
HERE THE DIRECTION OF COUPLE FORCES CAN BE FOUND WITH
HELP OF FLAMING LEFT HAND RULE .WHICH STATED THAT IF WE
POINT OUT THE INDEX FINGER IN THE DIRECTION OF MAGNETIC
FIELD AND THE MIDDLE FINGER IS IN THE DIRECTION OF CURRENT
THE THUMB WILL SHOWS THE DIRECTION OF MAGNETIC FORCE. AS
SHOWN IN THE FIGURE BELOW.
11. Why we use Dc motor not
AC motor?
Due to below reasons we use DC motor:
High starting torque.
Speed control over a wide range, both below and
above normal speed
Quick starting, stopping
12. Blades:
ON THE BASIS OF BLADES THERE ARE TWO TYPES OF
WIND TURBINES.
VERTICAL AXIS WIND TURBINE (VAWT)
HORIZONTAL AXIS WIND TURBINE (HAWT)
13. (1) VAWT
IN VAWT GENERATOR IS MOUNTED AT THE BASE OF
THE TOWER AND THE BLADES ARE WRAPPED
AROUND THE SHAFT VERTICALY.
14. (2)HAWT
In HAWT, blades are on the top, spinning in the air,
wrapped horizontality on the shaft and are most
commonly seen.
15. Calculation of Wind Power
•Power in the wind
– Effect of swept area, A
– Effect of wind speed, V
– Effect of air density, R
Swept Area: A = πR2 Area
of the circle swept by the
rotor (m2).
Power in the Wind = ½ρAV3
17. Number of Blades – One
Rotor must move more
rapidly to capture same
amount of wind
Blades easier to install
because entire rotor can
be assembled on ground
Captures 10% less energy
than two blade design
18. Number of Blades - Two
Advantages &
disadvantages similar to one
blade
Need teetering hub and or
shock absorbers
Capture 5% less energy than
three blade designs
19. Number of Blades - Three
Balance of gyroscopic
forces
Slower rotation
120 Angel apart from each
other
10% more Energy than Two
blades rotor
22. Tip-Speed Ratio
Tip-speed ratio is the ratio of the
speed of the rotating blade tip
to the speed of the free stream
wind.
There is an optimum angle of
attack which creates the
highest lift to drag ratio.
Because angle of attack is
dependant on wind speed,
there is an optimum tip-speed
ratio
ΩR
V
TSR =
Where,
Ω = rotational speed in radians /sec
R = Rotor Radius
V = Wind “Free Stream” Velocity
ΩR
R
23. TOWER
The Structure or Tower consists of
Rotor
Blades
Hub
Low-speed shaft
Bearings
Gearbox
Generator
Main frame
Electrical connections
Cooling systems
Assembly and installation
Foundation/support structure
24. DRAWINGS IN AUTOCAD
3 Feet
7.5Feet
2Feet
Blades
Gear Box
Base
Generator
Rotor
Hub
Angle=120
Bearing
Tower
1:2
27. Length of Tower
and Wind Speed
Speed of Wind increases exponentially as the
height of tower increases. From this graph, one
can see that at low heights, the wind speed
increases significantly at first, but at higher heights
the rate of increase is much less.
28. Energy In the Wind
Ew = (Ws
3 *(1.2252/2)*As) /1000
Ew= Energy in the Wind
Ws= Wind Speed (mph)
As= Swept Area of Blades
30. APPLICATIONS:
IT CAN BE USED TO PROVIDE ELECTRICITY TO
SECURITY AND CCTV CAMERAS
ALSO TO POWER STREETLIGHTS AND TRAFFIC
MANAGEMENT SYSTEMS
IT IS USED TO DRIVE SAILBOATS
IT IS USED TO LIGHTING UP THE SMALL VILLAGES
AND URBAN AREAS HOME
IT IS USED IN INDUSTRIES DUE TO ITS LOW COSTS
BY USING IT WE CAN AVOID CONVERTING POWER
FROM AC TO DC OR DC TO AC. EVERY TIME THE
POWER IS CONVERTED, YOU WILL LOSE 25% TO 30%
OF THE POWER