Piezo Electric Transducer

Prudhvi Mulagacherla

Contents

• Introduction• Piezo electric transducer(nanogenerator)• Inside a nanogenerator• Working principle• Sources which nanogenerator can exploit• Applications• Limitations

Introduction

Developers of Nanogenerators

Dr. Zhong Lin (Z.L.) Wang and his colleagues at Georgia Institute of Technology, Georgia State, USA have made significant leaps in developing nanogenerators over the last decade.

• Piezoelectric Transducer- When an external force is applied on to a quartz crystal, there will be a change in the voltage generated across the surface. This change is measured by its corresponding value of sound or vibration.

Piezoelectric Transducer• Ability to create electrical potential when compressed,

expanded or changed in shape (Mechanical energy to Electrical energy).

• Made up of Zinc Oxide wires called Nanowires.• Produces 45mv whenever the zinc wire is pulled back and

forth.• Wires have

diameter of : 100-300 nm Length of : 10-100 micron

Inside A Nanogenerator• Consists of an integrated

circuit.• Nanowire bends and generates

an electrical charge.• Several electrodes capture

power from millions of nanowires.

How it works?

• Working principle of Nanogenerator where an individual nanowire is subjected to the force exerted perpendicular to the growing direction of nanowire.

Sources which Nanogenerators can exploit• For Large scale applications (from wherever periodic

kinetic energy exists) :1. Wind,2. Ocean Waves.

• Small scale applications :1. Tiny physical motion,2. Inhalation of lung,3. Heartbeat,4. Muscle movement,i.e. Any kind of movement!!

MOBILE KEYPADS & KEYBOARDSCrystals laid down under keys of

mobile unit and keyboard.For every key pressed vibrations

are created.These vibrations can be used for

charging purposes.

GYMS AND WORKPLACESVibrations caused from

machines in the gym.At workplaces,

piezoelectric crystal are laid in the chairs for storing energy.

Utilizing the vibrations in the vehicle like clutches, gears etc.

POWER GENERATING BOOTS OR SHOESIdea was researched in US.To power the battlefield

equipment by generators embedded in soldier boots.

Idea was abandoned due to the discomfort.

ADVANTAGES DISADVANTAGESUnaffected by external electromagnetic fields.

They cannot be used for truly static measurements

Pollution FreeCan pick up stray voltages in connecting wires.

Low Maintenance Crystal is prone to crack if overstressed.

Easy replacement of equipment.

May get affected by long use at high temperatures.

CONCLUSIONPiezoelectricity is a revolutionary source for “GREEN ENERGY”. Flexible piezoelectric materials are attractive for power harvesting

applications because of their ability to withstand large amounts of strain. Convert the ambient vibration energy surrounding them into electrical energy.

Love India

Jai Hindh