13-09-2014, 02:43 PM
Wind Energy and Wind Turbine
Wind Energy.ppt (Size: 557 KB / Downloads: 40)
Wind Power - Introduction
Wind power is good renewable, clean and free
source of energy for power production
Reduce dependence on fossil fuels including
imported oils
Reduce emission of greenhouse gas and other
pollutant
One major concern is the noise – can be improved
Intermittency and variability of the wind
Wind Energy Conversion
Wind power describes the process by which the wind is used to generate mechanical energy or electrical energy.
Wind energy is the kinetic energy of the large mass of air over the earth surface.
Wind turbines converts the kinetic energy of the wind into mechanical energy first and then into electricity if needed.
The energy in the wind turns propeller like blades around a rotor shaft.
- The rotor is connected to the main shaft, which spins a generator to create electricity.
Common Power Control Methods
Pitch control
- blade pitch and blade angle of attack is decreased
with wind speed greater than rated speed.
- Wind speed and power output and power out put are
continuous monitored by sensors
- Need sophisticated control mechanism
Stall control
- blades are designed in such a that with increase in
wind speed, the angle of attack increases.
- Pressure variation at the tp and bottom surface
changes causing flow separation and vortex shedding
- kills lift forces and leads to blades stalling
- Need very sophisticated blade aerodynamic design