Question

1. You want to conduct an experiment to understand how the power generated by a wind turbine is affected by the speed of the wind. Write your hypothesis (1point) and explain how you can conduct the experiment (assume that you’re in laboratory conditions like we preformed the Wind Turbine experiment) eg the experiment needed and the procedure of the experiment (1 point). Which parameters/conditions in the experiment should be kept under control and which parameters should be observed to test the hypothesis? (1 point)

Answer 1

SOLUTION::

Wind turbines operate on a simple principle. The energy in the wind turns two or three Propellers around a rotor. The rotor is connected to the main shaft, which rotates within a stator surrounded by copper wire loops. Electromagnetic induction is created and

electricity is generated

>>Power is directly proportional to cube of velocity as...

The power developed from a wind turbine can be calculated from the formulae

Power = . 1/2.ρ.Av^3.Cp
ρ – Air density, kg/m2
A – Area of blade coverage, determine through knowledge of blade length, m2
v – Wind speed, m/sec
Cp - Power coefficient where Cp,max = 0.59.

>>Parameter which should kept under control is [Control the pitch]:

When wind speed is not higher than the rated speed, the blade incidence stay near the angle 0°
(highest power point). When wind speed is higher than the rated speed, the pitch control
mechanism changes blade incidence so that the generated power remains within the allowed
range. This acts as both an optimisation control feature as well as a protection method
preventing runaway states of the generator .

Procedure:

1. High speed Wind is being passed through aerodynamic wings of rotor.

2. Due to movement of air over wing high pressure and low pressure area created over the wing and wing starts lifting i.e start rotation.

3. Blades rotates low speed shaft of the order of 7-10 RPM .

4. A gear box transmites this power and change it to high RPM

5. A high speed shaft rotates at about 1500 RPM.

6. This is connected to shaft of generator which changes electric field across it and electricity generated.

7. Keep on changing speed of wind , keeping other parameters constant.

8. Record the data.