3. Content
o History
o Introduction
o What is piezo material
o Working
o Output power
o Road power generator
o Road power Generator –block diagram
o Construction of road power generator
o Working of road power generator
o Application of piezoelectricity
o Advantage and disadvantage
o Conclusion
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4. History
The name Piezo originates
from the Greek word
piezein, which means to
squeeze or press.
The piezoelectric effect
was first proven in 1880
by the brothers Pierre
and Jacques Curie.
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5. Introduction
In literature, piezoelectricity is a piezoelectric
effect of some materials like crystal leads to
produce energy under pressure.
The isolation between positive and negative
electrical charges in molecules will cause dipole
moment that cause the movement from
negative to positive charge depending on the
volume of the crystal.
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6. Introduction
In the piezoelectric crystal, when a pressure is
taking place, the molecular dipole moment will
produce electricity
The piezoelectric effect is a linear
electromechanical relationship between
mechanical movement and
the electric energy of piezoelectric materials
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7. What is Piezoelectric Material?
Piezoelectric Material is one that possesses the property
of converting mechanical energy into electrical energy
and vice versa.
Compression
Effect: Decrease in volume and it has a
voltage with the same polarity as thematerial
Tension
Effect: Increase in volume and it has a voltage
with opposite polarity as the material
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Fig 1.1(a) Fig 1.1(b)
8. Material used in Piezoelectricity
NATURAL SYNTHETIC
Quartz Lead zirconate titanate (PZT)
Rochelle Salt Zinc oxide (ZnO)
Topaz Barium titanate (BaTiO3)
Sucrose Gallium orthophosphate (GaPO4)
Tendon Potassium niobate (KNbO3)
Silk Lead titanate (PbTiO3)
Enamel Lithium tantalate (LiTaO3)
Dentin Langasite (La3Ga5SiO14)
DNA Sodium tungstate (Na2WO3)
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9. Working
The positive & negative charges are
symmetrically distributed in a crystal.
Piezoelectric ceramic materials are not
piezoelectric until the random ferroelectric
domains are aligned by a process known as
POLING.
Polingconsists of inducing a DC voltage
across the material.
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11. When pressure is applied to an object, a
negative charge is produced on the expanded
side and a positive charge on the compressed
side.
Once the pressure is relieved, electrical current
flows across the material.
Working
11Fig 1.3: working of piezo material
12. The output voltage obtained from a single
piezoelectric crystal is in millivolt(mV) range, which is
different for different crystals.
And the wattage is in microwatt(µW) range.
In order to achieve higher voltages, the
piezoelectric crystals can be arranged in series.
Used to charge batteries for backup
supplies or to power low-power microprocessors.
Output power
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14. Road Power Generator
The piezoelectric effect is a linear electromechanically
relationship between mechanical movement and the electric
energy of piezoelectric materials.
A smart road of one kilometer in distance could supply
enough energy for 40 houses. The upgrade of roads to smart
roads could generate much power to improve the national
power grid.
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15. Road power Generator –block diagram
Activator plate Linear to rotary motion with rack and pinion
mechanism
This small speed
converted
into large one by pulleys
Using flywheel for
uniform speed
Flywheel connected
to dc generator or
dynamo
Dc controller for
regulating current
Inverter for converting 12v DC to
220v AC
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17. Construction of RPG
A small ramp installed on the road, connected within a
generator that converts kinetic energy generated by the
pressure of vehicle on the ramp into electrical energy
through movable arm, horizontal stick, gear box and fly
wheel as explained in Fig. 1.4.
The ramp is different from ordinary speed breakers as
the ramp is smooth and safe and it could make
from fiber glass or plastic to prevent damage to the
vehicles
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18. Working Of RPG
The ramp height is 5 cm horizontally and connected
to the movable arm.
When the vehicle pressed down
the ramp, the mechanical movement transferred
through the movable arm to force the horizontal stick
to rotate and this motion transferred to the fly wheel
through the gear box.
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19. Working of RPG
The gear box will apply enough torque to double the
rotational speed of the fly wheel to store enough
amount of energy in it.
The prober rotation of the fly wheel will force the
alternator to generate power.
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20. Working of RPG
Formula:
Fw = (M× Ne × ȵ) ÷(r ×Nw)
Where
M= net torque
Ne = engine speed
ȵ= engine efficiency
r = radius of wheel
Nw =wheel speed
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24. Gyms and workplaces
Vibrationscaused from
machines in the gym.
At workplaces,
piezoelectric
laid in the
crystal are
chairs for
storing energy.
Utilizing the vibrations in
the vehicle like clutches,
gears etc.
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25. Power generating boots or shoes
Idea was researched in
US.
To power the battlefield
equipment by generators
embedded in soldier
boots.
Idea was abandoned due
to the discomfort.
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26. Floor mats and people powered
dance clubs
Series of crystals can be laid below the floor mats, tiles
and carpets.
One footstep can only provide enough electrical current
to light two 60-watt bulbs for one second.
[source: Christian Science Monitor].
When mob uses the dance floor, an enormous voltage is
generated.
This energy is used to power the equipment of night
clubs.
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28. Mobile keypads & keyboards
Crystals laid down under
keys of mobile unit and
keyboard.
For every key pressed
vibrations are created.
These vibrations can be
used for charging
purposes.
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29. Other applications
Electric cigarette lighter:
Pressing the button of the lighter causes a spring-loaded
hammer to hit a piezoelectric crystal, producing a sufficiently
high voltage that electric current flows across a small spark gap,
thus heating and igniting the gas.
As sensing elements:
Detection of pressure variations in the form of sound is the
mostcommon sensor application, e.g. piezoelectric
microphones. Sound waves bend the piezoelectric material,
creating a changing voltage.
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30. Advantage
Unaffected by external electromagnetic fields.
Pollution Free
Low Maintenance
Easy replacement of equipment.
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31. Disadvantage
They cannot be used for truly static
measurements
Can pick up stray voltages in connecting wires.
Crystal is prone to crack if overstressed.
May get affected by long use at high
temperatures
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32. Conclusion
Considered as sustainable, clean source of energy
and environmentally
friendly .
Convert the ambient vibration energy surrounding
them into electrical energy.
Electrical energy can then be used to power other
devices or stored for later use.
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