WIND POWER PLANT
INRODUCTIONEnergy is an important part of any country’s economy. Today major energy need in a
country is achieved by using conventional sources of energy. It includes coal, natural gas, nuclear fuel, etc. But
these sources are limited on earth .
Looking towards the environment effect as thermal plant releases smoke and ash which causes air pollution
Nuclear power plant releases radioactive waste which are hazardous and cause air and land pollution.
Due to these factor we concern our idea toward non conventional sources of energy.
Non –conventional sources of energy are environmental friendly, easily available
on earth .
Wind energy has evolved as one of the non conventional sources of energy . It is an indirect form of solar
energy. Wind power plant extract energy from wind and convert it into mechanical energy which is used by
turbine to convert it into electrical energy.
Cause of wind flowDue to non uniform heating of land and water by solar energy, air nearer to equator heats
up quickly , these hot air tend to move upward because of less density ,The air vacancy created is filled by
cold air coming from poles .
Air carrying momentum is known as wind. Turbine blades as barrier which extract power from wind.
Advantages of wind energy

Wind energy is available in the country situated on bank of the sea.

Wind power plant does not require any additional source of energy for power generation.

It is pollution free and eco-friendly.

Both type of plant large scale and small scale can be constructed.
Wind in India
Studies shows that wind in India is varying in nature. Wind direction changes with season .
Some state like Tamilnadu, Gujrat has large potential of wind energy.
Parts of wind power plant
Rotor blade
Blade extract power from the wind. When wind forces the blade it transfers some energy to rotar.
Betz’s coefficient  Theoretical studies show that ideal wind turbine extract 60 % of total wind energy.
 That is maximum fraction of power that can be extracted by wind turbine is 60%.Therefore
shape and size of blade will determine turbine performance.
Shaft
Wind turbine shaft is connected to centre of rotor .when the rotor spins the shaft spins as well and rotor
transfers rotational energy to shaft .
Generator
Generator is a device which converts mechanical energy into electrical energy . Generator is based on the
principle of electromagnetic induction.
Gearbox
Gear box contains gear which are mechanically coupled to each other. Gear convert high speed-low torque
to low speed- high torque.
Turbine efficiency
Turbine efficiency = Na * Ng * Nc * Ngen
Where
Na = aero turbine efficiency
Ng= gearing efficiency
Nc = mechanical coupling
Ngen = generator efficiency
Our wind power plan
Our wind plant is horizontal axis wind plant as in India wind blows much higher than our rooftops.
We use variable pitch gear as coupling device with variable speed controller using lever and crank-shaft
mechanism.
Type of material for blade –
Wood (pine & spruce)
 Easy to carve
 Resistance to fatigue
Diameter of blade-5 meter
Number of blade –when the number of blade increases turbine will stops more wind energy i.e lift force on
Blade increases but axial thrust(drag)also increases which is counterbalanced by mechanical design .we use
three blades which are so adjusted on hub so as when speed increases there will be increase in drift and decrease
in drag.
Gear system and speed controller-we use variable pitch gear as coupling device which is mounted on
generator. Wind turbine rotator shaft is connected with a gear which is coupled through variable pitch gear by
chain which passes over a secondary gear .secondary gear is pivoted with crank shaft mechanism by a lever other
side of secondary gear is connected with spring for it’s sidewise movement.
Crank is attached with a motor which is connected with coil inside which there is a U –shaped permanent
Magnet.
Generator -we use three phase generator as it extract more power from rotor (three times more than
single phase). If more power is extracted there will less desipition of wind energy as vibrational energy.
Rectifier-we use six diodes to make rectifying circuit to convert AC into DC . diodes are provided with better
heat sink
Voltage regulator-voltage regulator circuit is drawn in figure.
Regulating operation
1. If the output voltage decreases , the increased base emitter voltage causes transistor to conduct more .
Thereby raising the output voltage –maintaining the output constant.
2. If the output voltage increases ,the decreased base emitter voltage causes the transistor to conduct less
Thereby reducing the output voltage –maintaining the output constant.
Battery storage
We use 12 V lead acid rechargeable battery as it’s energy/price ratio is more . it has long life
High charge\ discharge cycle. Easily available in market.
1.2.3--- Ball bearing system
4------- blade
5 - variable pitch gear
6 - generator
13 - diode
14 - crank shaft
11 U shaped magnet
10 - coil
8 - chain
Working - whole system is set up in low wind speed with chain on the upper most variable pitch gear
When wind increases it generates current in coil on free end of rotor which pull secondary
gear and draws the chain in second pitch on variable gear hence maintaining speed.
when wind speed decreases spring pull back chain to large diameter of variable pitch gear
hence maintaining speed of generator by increasing speed of variable pitch gear.