7. 2 July
2020
U.ARAVIND,
LECT/MECH
7
• The circulation of air in the
atmosphere is caused by the
non-uniform heating of the
earth’s surface by the sun
• Wind speeds increase with
height
• Air movement is affected by
earth rotation
8. 2 July
2020
U.ARAVIND,
LECT/MECH
8
Wind Speed Remarks
Below 3 m/s Unsuitable for wind power
system
3 – 4.5 m/s May not reliable for wind
power systems
4.5 – 10 m/s Suitable for wind power
system
11. 2 July
2020
U.ARAVIND,
LECT/MECH
11
The output of the wind energy
converter is depends on
The wind speed5 TO 20
The cross section of the wind
swept by rotor
The overall conversion efficiency
of the rotor, transmission system
and generator , pump
12. • Wind mill converts the kinetic
energy of the wind into mechanical
energy
• Kinetic energy = ½ m V2
• Mass, m = ρA
V
• Kinetic energy = ½ ρA V3 watts
Wind power α V3
2 July
2020
U.ARAVIND,
LECT/MECH
12
15. 1.Circumferential force
• Acting in the direction of wheel
rotation
• It provide torque
• T = {ƞρDV3 }/ 8Ng N
i c
2. Axial force
• Acting in the direction of wind stream
• It provide thrust
• Fx(max) = {ПρD2V2 } / 9gc
U.ARA
iVIND,
LECT/MECH
44
2 July
2020
17. 1. Drag force
• Acting in the of wind direction
2. Lift force
• Acting perpendicular to the wind direction
Lift
Drag
2 July
2020
U.ARAVIND,
LECT/MECH
17
21. 2 July
2020
U.ARAVIND,
LECT/MECH
21
Wind speed
Turbine height
Site cost
Ground nature
Local ecology
Transportation
Altitude of the site
Nearness of the local user
Environmental facts
23. I. Based on axis of rotation
a) Horizontal axis machines
b)Vertical Axis machines
II. Based on size
a) Small scale machines (upto 2kW)
b) Medium scale machines (2-
100kW)
c) Large scale machines (100kW and
)
2
July
u
202
p
0
U.ARAVIND, LECT/MECH 54
24. 2 July
2020
U.ARAVIND,
LECT/MECH
24
III. Based on the type of Output power
a) DC output
b) AC output
IV. Based on the rotational speed
a) Constant speed with variable pitch
blades
b) Nearly constant speed with fixed
pitch blades
c) Variable speed with fixed pitch
blades
25. 2 July
2020
U.ARAVIND,
LECT/MECH
25
V.Based on the utilization of output
a) Battery storage
b) Direct connections to an
electromagnetic energy
converter
c) Interconnection with
conventional electric utility grid
d) Thermal potential storage
39. 2 July
2020
U.ARAVIND,
LECT/MECH
39
I. Horizontal Axis wind machines
a) Horizontal axis using two
aerodynamic blades
b) Horizontal axis Propeller type
using Single blade
c) Horizontal axis multi blade type
d) Horizontal axis Dutch type
45. 2 July
2020
U.ARAVIND,
LECT/MECH
45
• The axis of rotation is
horizontal
• It consists of rotor, supporting
structure, gear box, generator
• Rotor blades made of metal or
composite materials
59. 2 July
2020
U.ARAVIND,
LECT/MECH
59
• The axis of rotation is vertical
• Its also known as Cross wind
axis machine
• No need of yaw control
mechanism
• Heavy components placed on
the ground
62. 2 July
2020
U.ARAVIND,
LECT/MECH
62
Schemes for electric
generation
Constant speed - constant
frequency system (CSCF)
Variable speed - constant
frequency system (VSCF)
Variable speed - Variable
frequency system (VSVF)
65. 2 July
2020
U.ARAVIND,
LECT/MECH
65
• When power generation is excess,
the excess energy would be stored
• Energy may be used in the varies
forms Heat, Mechanical, Electrical
66. •For low & intermediate
electric power - Battery
storage
2 July
2020
U.ARAVIND,
LECT/MECH
66
73. • The computer
• Emergency stop
• Revolution counter
• Parachutes
• Lightning rod
• Vibration sensor
•E
2 July
l20
e
20 ctronic th
U.A
e
RAV
r
IND
m
, LECT/M
o
ECH
10
4