PIEZO ELECTRICITY GENERATOR

PIEZO ELECTRICITY GENERATOR  



INDEX


Sr. no.
Name
1
introduction
2
What is piezoelectricity generation
3
How it works
4
Application of piezoelectricity
5
A simple project of piezoelectricity generation
6
Schematic diagram 
7
List of component
8
Cost estimating
9
use
10
Reference
11
conclusion


Introduction

There are lots of ways are founded to produce electricity and piezoelectricity is one part of these way.

Piezoelectricity was discovered in 1880 by French physicists Jacques and Pierre Curie.

The word piezoelectricity means electricity resulting from pressure. It is derived from the Greek piezo or pieze in which means to squeeze or press, and electric or electron, which means amber, an ancient source of electric charge.

Piezoelectricity is the electric charge that accumulates in certain solid materials (such as crystals, certain ceramics )

The piezoelectric effect is understood as the linear electromechanical interaction between the mechanical and the electrical state in crystalline materials with no inversion. The piezoelectric effect is a reversible process in that materials exhibiting the direct piezoelectric effect (the internal generation of electrical charge resulting from an applied mechanical force) also exhibit the reverse piezoelectric effect (the internal generation of a mechanical strain resulting from an applied electrical field). For example, lead zirconate titanate crystals will generate measurable piezoelectricity when their static structure is deformed by about 0.1% of the original dimension. Conversely, those same crystals will change about 0.1% of their static dimension when an external electric field is applied to the material. The inverse piezoelectric effect is used in the production of ultrasonic sound waves.


What is piezoelectricity generation? 

Squeeze certain crystals (such as quartz) and you can make electricity flow through them. The reverse is usually true as well: if you pass electricity through the same crystals, they "squeeze themselves" by vibrating back and forth. That's pretty much piezoelectricity in a nutshell but, for the sake of science, let's have a formal definition:
Piezoelectricity (also called the piezoelectric effect) is the appearance of an electrical potential (a voltage, in other words) across the sides of a crystal when you subject it to mechanical stress (by squeezing it).
In practice, the crystal becomes a kind of tiny battery with a positive charge on one face and a negative charge on the opposite face; current flows if we connect the two faces together to make a circuit. In the reverse piezoelectric effect, a crystal becomes mechanically stressed (deformed in shape) when a voltage is applied across its opposite faces.

What causes piezoelectricity?



Think of a crystal and you probably picture balls (atoms) mounted on bars (the bonds that hold them together), a bit like a climbing frame. Now, by crystals, scientists don't necessarily mean intriguing bits of rock you find in gift shops: a crystal is the scientific name for any solid whose atoms or molecules are arranged in a very orderly way based on endless repetitions of the same basic atomic building block (called the unit cell). So a lump

of iron is just as much of a crystal as a piece of quartz. In a crystal, what we have is actually less like a climbing frame (which doesn't necessarily have an orderly, repeating structure) and more like three-dimensional, patterned wallpaper.
Artwork: What scientists mean by a crystal: the regular, repeating arrangement of atoms in a solid. The atoms are essentially fixed in place but can vibrate slightly. 

In most crystals (such as metals), the unit cell (the basic repeating unit) is symmetrical; in piezoelectric crystals, it isn't. Normally, piezoelectric crystals are electrically neutral: the atoms inside them may not be symmetrically arranged, but their electrical charges are perfectly balanced: a positive charge in one place cancels out a negative charge nearby. However, if you squeeze or stretch a piezoelectric crystal, you deform the structure, pushing some of the atoms closer together or further apart, upsetting the balance of positive and negative, and causing net electrical charges to appear. This effect carries through the whole structure so net positive and negative charges appear on the opposite, outer faces of the crystal.

The reverse-piezoelectric effect occurs in the opposite way. Put a voltage across a piezoelectric crystal and you're subjecting the atoms inside it to "electrical pressure." They have to move to rebalance themselves—and that's what causes piezoelectric crystals to deform (slightly change shape) when you put a voltage across them.

How it works

Here's a quick animation showing how piezoelectricity occurs. It's somewhat simplified, but it gives you the basic idea.

Normally, the charges in a piezoelectric crystal are exactly balanced, even if they're not symmetrically arranged.
The effects of the charges exactly cancel out, leaving no net charge on the crystal faces. (More specifically, the electric dipole moments—vector lines separating opposite charges—exactly cancel one another out.)
If you squeeze the crystal (massively exaggerated in this picture!), you force the charges out of balance.
Now the effects of the charges (their dipole moments) no longer cancel one another out and net positive and negative charges appear on opposite crystal faces. By squeezing the crystal, you've produced a voltage across its opposite faces—and that's piezoelectricity.

Application of piezoelectricity

     1.  production and detection of sound

     2.  generation of high voltages

     3.  electronic frequency generation

     4.  microbalances

     5.  To drive an ultrasonic nozzle

     6.  ultrafine focusing of optical assemblies

     7.  scanning probe microscopes Such as STM, AFM, MTA, SNOM, etc.,

    It is also the basis of a number of scientific instrumental techniques with atomic resolution

A simple project of piezoelectricity generation



This is the simple project of piezoelectricity generation which you can make at your home without any skill required.

Equal and continues pressure on piezo plate produce the electricity. it takes 1 min to get 3 voltage and this voltage just flash the LED.  The important thing continues pressure on the piezo plate that must require otherwise voltage drop down issue will generate.

WATCH THIS TO LEARN HOW IT WORKS

    

Schematic diagram



This is the schematic diagram of piezoelectricity generation model here in this figure 6 component is used a piezo plate, diode, resistor, capacitor, LED and switch.


List of component


1.          Switch
2.          Piezo plate buzzer
3.          Resister
4.          Capacitor
5.          Diode
6.          LED


1.Switch

Here we used this switch to control the voltage of the capacitor.











2.Piezo plate buzzer
This is piezo plate buzzer and it is used to generate the electrical energy through mechanical pressure therefore here the mechanical energy convert into electrical energy.




3.Resister
    470 Ω resistor is used here to manage the voltage.







4.Capacitor
100 µF capacitor is used to store the voltage which produced by the piezo plate.







5.Diode
    Here Diode id used to stable the voltage that coming through the piezo plate.






6.LED
           LED is used to show the generated electricity as a little flash.








Use
1.          As science project.
2.          To demonstrate the piezoelectricity generation method.
3.          For education model.

Reference
           
           1.  Wikipedia
           2.  Youtube
           3.  Google search 

Conclusion
This is the simple piezoelectricity generator it noting required any skill to build at home after a long study it can be changed into battery charging device.