WECS1

PS 7007 WIND ENERGY CONVERSION SYSTEMS

VENKATA SUBRAMANIAN.M, AP/EEE 1

UNIT I INTRODUCTION •Components of WECS •WECS schemes •Power obtained from wind •simple momentum theory •Power coefficient •Sabinin’s theory •Aerodynamics of Wind turbine

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 Of all the forces of nature, I should think the wind

contains the largest amount of motive power. 

All the power exerted by all the men, beasts, running-water, and steam, shall not equal the one hundredth part of what is exerted by the blowing of the wind.

 Quite possibly one of the greatest

discoveries, will be the taming and harnessing of it.

– Abraham Lincoln - 1860

Among renewable energy sources, wind energy generation has been noted as the most rapidly growing technology because it is one of the most cost effective and environmental friendly means to generate electricity from renewable sources. FUNDAMENTAL CONCEPT Wind energy conversion systems convert the kinetic energy of the wind into electricity or other forms Of energy. flow diagram of the wind energy conversion system.

There are huge variations in size, but all wind turbines from the smallest to the largest work in the same way.  The overall configuration is identical. Each system consists of a rotor (blades) that converts the wind’s energy into rotational shaft energy, a nacelle (enclosure) containing a drive train, and a generator . The energy that moves the wind (kinetic energy) moves the blades. This energy in turn moves the drive train (mechanical energy) is then turned into electricity (electrical energy) in the generators and then stored in batteries or transferred to home power grids or utility companies for use in the usual way.

COMPONENTS OF A WIND TURBINE SYSTEM Typical wind turbines involve a set of rotor blades (usually three) rotating around a hub. The hub is connected to a gearbox and a generator, located inside the nacelle, which houses the electrical components. The basic components of a wind turbine system are shown below and outlined

V2

Rotor power

P  21 ρAV1 C p 3

where : C p  rotor power coefficient V1

  air density A  rotor swept area Ideal (Betz limit) Cp  0.593 w here: V2  13 V1 (wind velocity slows by 2/3)

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Horizontal axis 3-bladed ( HAWT ) VAWT )

Horizontal axis 2-bladed

Vertical axis (

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‘Top box’:

Wind Sensors

low voltage, control…

GE 1.5 wind turbine 52 metric ton nacelle 35 metric ton rotor

High-speed coupling

Mechanical brake Gearbox

Generator

Pitch drive 6-ft

Pitch bearing Bed Frame

Hub

Yaw drives Yaw bearing

Rotor main shaft Main bearing Hokie Bird is registered trademark of Virginia Tech

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