DESIGN AND FABRICATION OF EFFICIENCY INCREASED ADVANCED WIND TURBINE SYSTEM
A windmill is a mill that converts the energy of wind into rotational energy by means of vanes called sails or blades. Centuries ago, windmills usually were used to mill grain, pump water, or both. Thus they often were gristmills, wind pumps, or both. The majority of modern windmills take the form of wind turbines used to generate electricity, or wind pumps used to pump water, either for land drainage or to extract groundwater. Wind turbine project is mini project.
In existing windmill the blades or vanes is uni-directional which remains in one direction. If we get wind in upward and downward direction it rotates and generate power, what about in left and right direction? So there is a need of 360 degree turning wind blades.
Wind energy is one of the most important types of renewable energy using which is inevitable in today’s world. Using this energy has been taken into consideration from the past and first it was used as windmills for daily use and now, in developed countries, it is utilized in different kinds of wind turbines with multi-megawatt power of energy generation. In our country, extreme reliance to non-renewable resources and production of pollutions in metropolises has encouraged the researchers and officials to find a renewable replacement, which is dependent on the construction and designing of wind turbines through the available technologies.
Currently two kinds of wind turbines, among different designs considered by the designers, are horizontal axis wind turbine (HAWT) and vertical axis wind turbine (VAWT), used mainly to generate power. In comparison, each one has its own advantages and disadvantages. Some advantages of vertical axis turbine are easy designing and construction, lower cost, no need to rotor yaw mechanism (Yaw) to find that wind direction and sound pollution and ecosystem damage reduction. Among its disadvantage are less efficiency, power production with higher fluctuation, lower speed of the blades and lower energy yield. However, there are also downfalls to the VAWM. Firstly, boundary layer affects from the ground influence the air stream incident on the VAWT, which in some cases leads to inconsistent wind patterns. Secondly, VAWT are not self – starting currently, an outside power source is required to start turbine rotation until a certain rotational speed is reached