wind turbine

WIND TURBINES

• Presented by-SHAKIL MUHAMMAD

UET PESHAWARPAKISTAN

HOW WIND TURBINES GENERATE ELECTRICITY

First, let’s answer a very important question.

What are Wind Turbines?

Wind turbines are devices that convert the wind’s kinetic energy into Electrical energy.

First Wind Turbine

Made by :Charles.J.BrushIn1887.

Wind turbines have a variety of shapes and sizes…

Types of Electricity Generating Wind Turbines

Small

Large

Intermediate

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But they’re all composed of the same 3 basic parts.

Basic Parts

A. Rotor Blades

Basic Parts

A. Rotor Blades

B. Shaft

Basic Parts

A. Rotor Blades

B. Shaft

C. Generator

Basic Parts

A. Rotor Blades

The rotor blades are the “wind catchers” of a wind turbine.

Basic Parts

A. Rotor Blades

They’re long projections that have aerodynamic designs.

Basic Parts

B. Shaft

The shaft is a rod that connects the rotor blades to the generator.

Basic Parts

B. Shaft

Its main purpose is to transfer the rotational mechanical energy of

the rotor blades to the generator.

Basic Parts

C. Generator

3 Basic Parts

Finally, the generator is a device designed to convert mechanical

energy into electrical energy.

C. Generator

3 Basic Parts

It uses the principle of electromagnetic induction.

Now that you know its basic parts, let’s understand how

wind turbines generate electricity.

Basic Processes

B. Converting to Electricity

A. Capturing Wind Energy

Basic ProcessesA. Capturing Wind Energy

Wind energy is captured using the wind turbine’s rotor blades.

Basic ProcessesA. Capturing Wind Energy

When wind passes through the blades, two aerodynamic forces are at work.

Basic ProcessesA. Capturing Wind Energy

LIFT

DRAG

Rotor Blade

After this, it’s time to convert the mechanical energy into electricity.

Basic ProcessesB. Converting to Electricity

When the rotor blades

turn,

Basic ProcessesB. Converting to Electricity

the shaft also turns.

Basic ProcessesB. Converting to Electricity

The Shaft then rotate

the generator

How Does a Generator Work?

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Basic ProcessesB. Converting to Electricity

Which makes the generator

produce electricity!

Large Wind Turbines

• 450’ base to blade• Each blade 112’• 163+ tons total• Foundation 20+ feet deep• Rated at 1.5 – 5 megawatt• Supply at least 350 homes

Increasing RPM

Other Processes Involved

You might notice that large wind turbines turn slowly.

Increasing RPM

Other Processes Involved

On average, their rotor blades rotate at a speed of 20 rpm

(rotations per minute).

Increasing RPM

Other Processes Involved

20 rpm is too slow to power up a generator!

Increasing RPM

Other Processes Involved

Large wind turbines use a gearbox to increase the rpm from 20 rpm

to as much as 2000 rpm!

Increasing RPM

Other Processes Involved

To understand the process, let’s examine these two gears:

Other Processes Involved

Gear A

Gear B

Increasing RPM

Other Processes Involved

Gear A

Gear B

Gear A has 9 gear teeth

Increasing RPM

Other Processes Involved

Gear A

Gear B

Gear A has 9 gear teeth

while Gear B only has 6.

Increasing RPM

Other Processes Involved

Gear A

Gear B

Gear A has 9 gear teeth

while Gear B only has 6.This would mean that 1 revolution

of Gear A would be equal to 1.5 (9÷6) revolutions for Gear B.

Increasing RPM

Other Processes Involved

Gear A

Gear B

Gear A has 9 gear teeth

while Gear B only has 6.So if Gear A revolves at a rate of

20 rpm, Gear B would revolve at a faster rate of 30 (20×1.5) rpm.

Increasing RPM

Braking Mechanism

Other Processes Involved

Overspeeding of the rotor blades can cause malfunctions on the

wind turbine’s system.

Braking Mechanism

Other Processes Involved

This is why a braking mechanism should exist to limit the maximum

speed of the rotor blades.

*Benefits*

• Renewable Energy source• Enviromental Friendly• Electricity is produced in very low cost

*Summary*

END

Questions???