ABSTRACT
This paper targets the transformation of mechanical energy to electrical energy using piezoelectric materials. With piezoelectric materials, it is possible to harvest power from vibrating structures. It has been proven that, micro to milliwatts of power can be generated from vibrating materials. In gadgets like mobile phones, television remotes, laptops and other devices which employ key depressions for operation, mechanical vibrations are produced while pressing the keys. If these vibrations are successfully harvested, the resulting energy could serve as an ancillary source of energy for charging the batteries.
This paper presents a model of piezoelectric transducer for a gadget like, mobile phone, prototype of the power scavenging circuit, and the overall circuit for charging the mobile battery using the generated energy. Index Terms—Charge development, Diaphragm type piezoelectric crystal, Key depressions, Piezoelectric effect.
Origin of the idea and Economic feasibility:
The idea pertains generally to a mechanism for capturing mechanical energy and converting it to electrical energy, and is particularly useful for continually charging or providing emergency power to mobile, laptops and battery powered devices that are handled or carried by people.
After a long travel to distant places, long time listening to music or watching videos on our mobile or laptop, they show us low battery power. And soon when we want to chat with our buddies . At that peak hour my mobile isn’t allowing me to,there started our idea of making a self-chager without searching for a plug point or a charger .Indeed,thats the point where our project got initiative..
As the project has components that were relatively cheaper and when piezo materials were orderd in huge quantity the cost reduces further.Hence in economic point of view it would come up to cost equalivalent to a cell adapter.More over this product will have much impact on present day environment,one can start charging this Mobile or laptop from anywhere and anytime
Uniqueness of invention:
• . The design presented here will be quite effective in providing an alternate means of power supply for the mentioned devices during emergency.
• now-days energy efficient and eco friendly electronic devices are much in need and demand so we thought of an idea that would charge the battery of electronic devices by using the property of piezoelectricity.with this we can charge the battery wherever we are ,without actually searching for the plug point.
Components required:
S.No. | Component Required | Range | Quantity | Availability |
1. | Schottky Diode(BATIS-05) | 0.3V | 2 | Yes |
2. | Capacitor | 10,000 MicroF | 2 | Yes |
3. | IC-LM2576 | (0-4)V | 2 | Yes |
4. | IC-74XXX | (0-4)V | 2 | Yes |
5. | Relay Switch |
| 1 | Yes |
6. | PIEZOELECTRIC MATERIAL(PZT) | (0-40)V | 1 | Yes |
7. | Dummy Mobile Phone |
| 1 | Yes |
8. | Bread Board |
| 1 | Yes |
9. | Multimeter | (0-30)V | 1 | Yes |
10. | CRO | (0-30)MHz | 1 | Yes |
11. | Soldering Iron |
| 1 | Yes |
12. | Function Generator | (0-20)MHz | 1 | Yes |
Design and description of circuit:
The basic block diagram of the proposed model is shown in Fig. . It consists of 3 main blocks, (a) piezoelectric power generation (b) rectification (c) storage of DC voltage. AC voltage is generated from the piezoelectric material which is rectified by the rectification block and then it is stored in a storage device such as a battery.
The overall circuit diagram of the entire process. The rectifier maybe either a full wave rectification circuit or a half wave rectification circuit based on the combination of diodes or a voltage double rectifier. Since a diode is being used in the rectifier, a p-n junction diode or a Schottky diode can be used. The Schottky diode has a threshold voltage which is smaller than that of a p-n junction diode. For example, if the diode is formed on a silicon substrate, a p-n diode may have a threshold voltage of approximately 0.065 volts while the threshold voltage of a Schottky diode is approximately 0.30 volts. Accordingly, the uses of Schottky diode instead of p-n diode will reduce the power consumption required for rectification and will effectively increase the electrical charge available for accumulation by the capacitor. When the electromotive force in the piezoelectricity generation section is small, a Schottky diode having a low rising voltage is more preferable. The bridge rectifier section provides rectification of the AC voltage generated by the piezoelectric section. By arranging the rectification section on a monolithic n-Si substrate, it is possible to form a very compact rectification section.
A typical diode can rectify an alternating current—that is, it is able to block part of the current so that it will pass through the diode in only one direction. However, in blocking part of the current, the diode reduces the amount of electric power the current can provide. A full-wave rectifier is able to rectify an alternating current without blocking any part of it. The voltage between two points in an AC circuit regularly changes from positive to negative and back again. In the full-wave rectifier.
Product description:
The idea goes like this: A sheet of piezo electric material is placed beneath the keypad of a mobile phone or a laptop, or otherwise the keys itself are made of the piezo material. when we press the keys we are supplying the mechanical energy to the piezo material ,then the piezo material responds to it by generating a voltage proportional to the force applied that charge produced will be send to the battery which stores the charge, thus the battery gets charged.
If the voltage generated is more than the battery specifications then the adapter used in between would bring it down to the required value.We also thought of using a switch just in front of the battery so that whenever there is no need for ‘piezo charging ‘ the switch can be opened and the charging stops ..
structure is deformed by about 0.1% of the original , dimension.Conversely lead zirconate titanate crystals will change about 0.1% of their static dimension when an external electric field is applied to the material.structure is deformed by about 0.1% of the original ,dimension.Conversely lead zirconate titanate crystals will change about 0.1% of their static dimension when an external electric field is applied to the material.
References :
While the pedantic among us may quibble with phrases like “self-powering portable electronics” and start blathering about the second law of thermodynamics, new research from Australia is pushing the limits of piezoelectric materials for turning pressure into electrical energy for mobile devices.
The researchers have published their work in the journal Advanced Functional Materials after demonstrating a method for combining piezoelectric materials with thin-film technology to produce more easily integrated into mass-production techniques.
"The concept of energy harvesting using piezoelectric nanomaterials has been demonstrated, but the realization of these structures can be complex, and they are poorly suited to mass fabrication,” says Dr. Madhu Bhaskaran, lead coauthor of the research. "Our study focused on thin-film coatings because we believe they hold the only practical possibility of integrating piezoelectrics into existing electronic technology."
When more easily integrated piezoelectric materials are combined with groundbreaking work in reducing the amount of energy consumed by electronic devices like that done by Eric Pop and his team at the University of Illinois at Urbana-Champaign’s Beckman Institute for Advanced Science and Technology, it seems possible that we may be able to run our small electronic devices for longer than a few hours before we have to plug them into an outlet.
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