PRESENTED BY
R.PRUTHVIRAJ

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ABSTRACT
This paper deals with wind power generation and the limitations that arise in generation. As energy crisis is very high in case of developing countries like India, there came urgent need to look for other sources of energy that are clean and pollution free as conventional sources causes pollution. Wind is a clean and plentiful source of energy. The wind is a non-conventional source similar to Solar, Sea, Geothermal and Biomass. A Windmill utilizes the wind energy and then converts it to electrical energy. For designing a windmill the size of the turbine, the size of the generator etc are required.
Wind turbines used to generate electricity are available with several power ratings and also in several physical sizes. Large wind turbines, which are usually installed in clusters called wind farms, can generate large amounts of electricity. Large wind turbines may even produce hundreds of megawatts (MW) of electricity enough to power hundreds of homes. Small wind turbines, which are generally defined as producing not more than 100 kW of power, are designed to be installed at homes, farms and small businesses either as a source of backup electricity, or to offset use of utility power and reduce electricity bills. Very small wind turbines (20 – 500 watt units) are used to charge batteries for sailboats and other recreational uses.
The problems faced in wind power generation are due to local impacts and system impacts. Local impacts deal with the impacts that occur in the vicinity of the wind turbine or wind farm. System impacts are the impacts that affect the behavior of the system as a whole. Using modern power electronics and special type of wind turbines that suit to the conditions can solve local impacts.
INTRODUCTION:
The wind is a clean and plentiful source of energy. Wind turbines used to generate electricity come in a wide variety of sizes. Large wind turbines, which are usually installed in clusters called wind farms, can generate large amounts of electricity. Large wind turbines may even produce hundreds of megawatts (MW) of electricity enough to power hundreds of homes. Small wind turbines, which are generally defined as producing no more than 100 kW of electricity, are designed to be installed at homes, farms and small businesses either as a source of backup electricity, or to offset use of utility power and reduce electricity bills. Very small wind turbines (20 – 500 watt units) are used to charge batteries for sailboats and other recreational uses.
It is estimated that wind potential is 1.6x10 7 MW which is same as world energy requirement. But the only problem is that wind speed is highly fluctuating. So many problems arise during power generation. So we mainly concentrate on the problems occurred during generation and how they can be rectified. The problems faced are due to local impacts and system impacts. Local impacts deal with the impacts that occur in the vicinity of the wind turbine or wind farm. System impacts are the impacts that affect the behavior of the system as a whole. Using modern power electronics and special type of wind turbines that suit to the conditions can solve local impacts. Designing turbines to withstand voltage variations of certain magnitudes can rectify system impacts to some extent. Controlling the rotor speed by gear mechanism can rectify problems due to high wind or computer aided techniques.
A small wind energy system could prove to be a practical and economical source of electricity for a home or farm if some or all of the following are true:
 Land requirement is at least one acre in size.
 Local zoning ordinances allow wind turbines.
 Electricity bills tend to be high.
 Property does not have easy access to utility lines, i.e. off electrical power grid.
 Comfortable with making long-term investments.
 Turbine is 250–300 m away from your neighbour’s house (closer for small turbines ie.1 kW).
1.1 WIND AVAILABILITY:
Constructing a wind turbine is economically viable at home or farm depends most strongly on the quality of the wind resource. Generally, average annual wind speeds of at least 4.0–4.5 m/s (14.4–16.2 km/h; 9.0–10.2 mph) are needed for a small wind turbine to produce enough electricity to be cost-effective. A very useful resource for evaluating a site for its wind energy potential is a wind resource potential map. It may be useful to check wind speed measurements that have been recorded at a local weather station.
It is important to consider that sitting factors at these weather stations, such as nearby trees and buildings, might influence any wind speed measurements. Also, the equipment at these stations is often located close to the ground, and that weather stations located at airports are usually sheltered from the wind. This means that wind speed measurements recorded at these stations might under represent the wind potential at the selected site.
For the most precise evaluation of the wind speed at your site, you need to purchase a wind resource evaluation system. While wind resource evaluation systems can be expensive, if your property is hilly and has unusual terrain features then it might be worth obtaining one. The most important component of a wind resource evaluation system is an anemometer. Anemometers are typically designed with cups mounted on short arms that are connected to a rotating vertical shaft.
The anemometer rotates in the wind and generates a signal that is proportional to the wind speed. If you do purchase an anemometer, you will also need to purchase something to record the readings made by the anemometer, and a tower or tripod to mount the whole system on.
For as little as 20,000 Rs. you might be able to purchase a wind totalized, which is a very simple type of wind resource evaluation system where the anemometer is linked to an odometer. The odometer is similar to those found in cars. After a period of time, the number recorded on the odometer, which represents the total “distance” the anemometer has turned, can be divided by the time passed since the odometer was last checked in order to determine the average wind speed over a period of time at a location.
More expensive wind resource evaluation systems are available. On many systems, a data logger continuously records wind speeds measured by the anemometer, and the data can be downloaded to a computer. These types of wind measurement systems provide a more accurate assessment of the wind resource at a location, but are much more expensive. For example, a system of this type, where the anemometer and data logger would be mounted on a 10 ft tripod, cost 2, 00,000 Rs. in 2002.
No matter what measurement system you install, for a small wind turbine a minimum of one year of data should be recorded and compared with another source of wind data. It is very important that the measurement equipment is set high enough to avoid turbulence created by trees, buildings or other obstructions. Readings would be most useful if they have been taken at hub height, or the elevation at the top of the tower where the wind turbine is going to be installed. If there is a small wind turbine system in your area, you may be able to obtain useful information from its owners about the annual electrical output of the system and, possibly, wind speed data. Such information could be extremely valuable as an alternative to installing a wind resource evaluation system.