49
Results and Discussion
The use of variable wind speed in the turbine has confirmed the rotational speed of the
wind turbine relative to the wind speed in a way the turbine operates which ultimately
confirms the production of maximum power point in varying wind speed [22, 23].
Thus, maximum power point can be captured in a varying wind speed by keeping the
tip ratio in its optimal value in a variable speed generation system of the wind where
the fundamental equation governing the mechanical power of this wind turbine is
confirmed by
P
C
AV
w
p
,
=
( )
1
2
3
λ β ρ
(3.29)
where ρ is the air density (kg/m
3
), C p is the power coefficient, A is the intercepting
area of the rotor blades (m
2
), V is the average wind speed (m/s), and λ is the tip speed
ratio. Here, the maximum value of the power coefficient C p is 0.593, also known as
Betz’s coefficient. The tip speed ratio (TSR) for wind turbine is defined as the ratio
of rotational speed of the tip of a blade to the wind velocity and thus it has been
described mathematically as
λ
ω
=
R
V
(3.30)
where R is the radius of the turbine (m), ω is the angular speed (rad/s), and V is the
average wind speed (m/s).
The energy generated by wind can be obtained by
Q
P
w
Time kWh
= ×(
)[
]
(3.31)
Simply, the various factors like the velocity of wind considering height are also
calculated by direct measurement of wind speed considering the error proneness
due to vegetation, shading, and obstacles in the vicinity [24]:
v
vZ
Z
Z
Z
Z
Z
( )
= ( )
ln
ln
r
r
0
0
(3.32)
where Z r is the reference height (m), Z is the height where wind speed is to be determined, Z 0 is the measure of surface roughness (0.1–0.25 for crop land), v(Z ) is the
wind speed at height Z (m/s), and v(Z r ) is the wind speed at reference height z (m/s).
Consequently, the change of the wind velocity considering the optimum turbine
generator speed corresponding to max power is determined to extract the maximum
power point tracking (MPPT) and is expressed by the optimum rotor speed of the
turbine drivetrain:
Results and Discussion
Results and Discussion
The use of variable wind speed in the turbine has confirmed the rotational speed of the
wind turbine relative to the wind speed in a way the turbine operates which ultimately
confirms the production of maximum power point in varying wind speed [22, 23].
Thus, maximum power point can be captured in a varying wind speed by keeping the
tip ratio in its optimal value in a variable speed generation system of the wind where
the fundamental equation governing the mechanical power of this wind turbine is
confirmed by
P
C
AV
w
p
,
=
( )
1
2
3
λ β ρ
(3.29)
where ρ is the air density (kg/m
3
), C p is the power coefficient, A is the intercepting
area of the rotor blades (m
2
), V is the average wind speed (m/s), and λ is the tip speed
ratio. Here, the maximum value of the power coefficient C p is 0.593, also known as
Betz’s coefficient. The tip speed ratio (TSR) for wind turbine is defined as the ratio
of rotational speed of the tip of a blade to the wind velocity and thus it has been
described mathematically as
λ
ω
=
R
V
(3.30)
where R is the radius of the turbine (m), ω is the angular speed (rad/s), and V is the
average wind speed (m/s).
The energy generated by wind can be obtained by
Q
P
w
Time kWh
= ×(
)[
]
(3.31)
Simply, the various factors like the velocity of wind considering height are also
calculated by direct measurement of wind speed considering the error proneness
due to vegetation, shading, and obstacles in the vicinity [24]:
v
vZ
Z
Z
Z
Z
Z
( )
= ( )
ln
ln
r
r
0
0
(3.32)
where Z r is the reference height (m), Z is the height where wind speed is to be determined, Z 0 is the measure of surface roughness (0.1–0.25 for crop land), v(Z ) is the
wind speed at height Z (m/s), and v(Z r ) is the wind speed at reference height z (m/s).
Consequently, the change of the wind velocity considering the optimum turbine
generator speed corresponding to max power is determined to extract the maximum
power point tracking (MPPT) and is expressed by the optimum rotor speed of the
turbine drivetrain:
Results and Discussion