Piezoelectic Wind Mill

This paper deals that the concepts of harnessing electrical energy from wind energy with piezoelectric crystals. In recent years, invention and development of power electronics devices have been increasing rapidly at a constant rate and these devices have been used in daily lives of people to ease their work and to make them comfortable. The feasibility of piezoelectric power generation system for the electric power system, with the conventional windmill, is discussed in this paper.

Design and implementation of a piezoelectric windmill which consists of the conventional windmill, piezoelectric flag, step up converters and filter circuits. The windmill of our design consists of two main components:

1.The blades connected to the axis of the tower by which normal operation of the windmill can be achieved and

2. The piezoelectric (flag or sheet) component attached to the top of the tower from which the additional energy can be achieved. As the wind blows the pressure of the wind helps to produce the electric energy which is, by the way, the principle of piezoelectric component. As the output given out from here is of varying frequency type and of low voltage, we need a constant frequency and high voltage output to operate the load. Therefore a suitable converter is used to achieve the constant frequency AC output which is then given to a suitable load for a test run.

In today’s world energy is the most important especially electricity is important. Renewable energy sources are expected to be the apt solution to solve the energy crisis problem. As natural resources and fossils fuels are on its verge of extinction, the researchers are striving hard to find an alternative energy source from nature. Due to the depletion of fossil fuels and drastic changes in climatic conditions, the use of natural renewable energy for production of power has become essential. Fossils fuels are depleted for generation of electric power and scientist predicts that fossils fuels will be exhausted in near future. The alternatives should not be harmful to the environment. Human beings on this

Planet has started to use energy harvesting technology in the form of windmill, geothermal and solar energy. Now renewable energy resources are focused more and researchers are currently involved in the use of piezoelectric crystals. After solar power wind energy is the most effective power since Wind is a clean and renewable energy source which has been used to produce electrical power and in addition to it piezoelectric transducers are used which converts vibrational energy to electrical energy. Piezoelectric crystals are typically low cost and easy to maintain and are available in abundance. Piezoelectric crystals used are ceramic quartz crystals and are one of the small-scale energy sources. Whenever piezoelectric crystals are subjected to mechanical vibration, they generate a small voltage. The windmills could also be used in shadowy environments. The proposed system consists of a conventional windmill with piezoelectric component boost circuits and filter circuits.

The piezoelectric windmill topology employs two systems for power generation so which two principles are employed. The first one is windmill which operates on a simple principle that converts the kinetic energy of air into mechanical energy and which in turn is converted into electricity. The second processor latter is described as i.e. the piezoelectric crystal converts the mechanical energy or vibrational energy of air into electrical energy. The piezoelectric effect converts mechanical strain into electric current or voltage. It is based on the fundamental structure of a crystal lattice. Certain crystalline structures have a charge balance with negative and positive polarization, which neutralize along the imaginary polar axis. When this charge balance is perturbed with external stress onto the crystal mesh, the energy is transferred by electric charge carriers creating a current in the crystal. Conversely, with the piezoelectric effect, an external charge input will create an unbalance in the neutral charge state causing mechanical stress.

The main aim of the system is to generate continuous electrical power of considerable amount from wind energy with piezoelectric crystals.The system consists perform the operation of a windmill which harnesses wind energy with minimum pickup speed to produce electrical power in addition to the electrical energy is obtained by using piezoelectric transducers which converts the vibrational energy or pressure of air to electrical energy which is used to operate the suitable light load.

EQUIPMENTS REQUIRED:

The following Apparatus required to design the piezoelectric windmill

? Windmill prototype

? Piezoelectric crystals

? Inverters

? Rectifiers

? Step up transformers

? Load (e.g. Bulb, fan etc.)

PIEZOELECTRIC TRANSDUCERS:

The piezoelectric material described above in the block diagram is mechanical energy or vibrational energy of air into electrical energy as the name indicates piezoelectric means electricity caused by pressure.

Today most commonly used piezoelectric transducers are lead zirconate titanate compositions and also piezo-polymers has also gained importance as well as acceptance in today’s market. The advantage of piezoelectric transducers is that it is available in low cost and is flexible as well as it can be obtained in any desired shape

BOOST CONVERTER:

A boost converter (step-up converter) is a DC-DC power converter that steps up the voltage from its input supply to its output (load). The advantage of this boost converter is that it is able to step up the voltage at its lowest as possible and the input is continuous and desirable. Boost converters or regulators are used in many instances from providing small supplies where higher voltages may be needed too much higher power requirements.

AUTOMATIC VOLTAGE REGULATOR:

A voltage regulator is designed to automatically maintain a constant voltage level. The automatic voltage regulator is used to regulate the voltage. It takes the fluctuating voltage and changes them into a constant voltage. The fluctuation in the voltage mainly occurs due to the variation in load on the supply system and automatic voltage regulators are commonly used

STEP UP TRANSFORMERS:

The step-up transformer is used in the above circuit to step up the 12v or 24v ac output of the inverter to 230v or required level so as to run the suitable load.

As the name indicates STEP UP means RAISING the voltage level. The step-up transformers are normally used in power systems so as to minimize the power losses as power is normally transmitted at high voltages.

WORKING:

The method showcased here is the electrical energy harvesting using piezoelectric effect in addition to the conversion of wind power to the electrical power using conventional windmill with a slight modification in its characteristics design. The power obtained from windmill as well as the power of piezoelectric crystal to operate load or stored in a battery for later use with an inverter. The power obtained from the windmill is stepped up with a step up transformer to a required level in order to operate the load. The intermediate process also consists of the automatic voltage regulator and filter circuits to filter the harmonics, stray inductance and to obtain the smooth fundamental output. The electrical power obtained from the piezoelectric crystal is then stepped to 230v to operate the light load.

ADVANTAGES:

1. Eco-friendly power generation.

2. Wind is free renewable energy resources.

3. The remote areas that are not connected to the electrical grid can produce their own power supply.

4. It reduces the country reliance on foreign imports of fossil fuels etc.

5.It is self -generating and it does not require any external additional source for its operation

6. Piezoelectric crystals are low cost and easy to maintain.

7. Piezoelectric crystals are flexible and compact.

8. The piezoelectric transducer is available in the desired shape

DISADVANTAGES:

1. Some piezoelectric transducers are water soluble and get dissolved in high humid environment

2. Its output may vary depending on the temperature conditions

3. It has high temperature sensitivity

4. The strength of the wind is not constant and it varies from zero to storm force. This means that wind turbines do not produce the same amount of electricity all the time. There will be times when they produce no electricity at all.

5. Many people feel that the countryside should be left untouched, without these large structures being built. The landscape should left in its natural form for everyone to enjoy.

6. Wind turbines operations are noisy. Each one can generate the same level of noise as a family car travelling at 60-70 mph.

7. Many people see large wind turbines as unsightly structures and not pleasant or interesting to look at. They disfigure the countryside and are generally ugly.

This project is developed which could be economical and an affordable solution to the people. It can be used in remote places where more power is required and there is no other choice of electric power available to them. Effective wind energy harvesting is realized and obtained by this method. The piezoelectric transducers are used since it is of low cost and easy to maintain and in today scenario it has gathered a huge response among the scientist for its developments in near future. As a whole piezoelectric windmill, an emerging alternative for renewable power production which does not harm the environment as well as additional power can be produced when does not depend on climatic conditions