AU2007100123A4 - Vetical axis wing turbine - Google Patents

Description

EDITORIAL NOTE There are 4 pages of description Field of Invention O This invention relates generally to vertical axis wind turbines that utilizes the kinetic 0 cenergy of moving air to provide rotational energy useable for generating electric power and/or other useful purposes. More particular this invention relates to a wind turbine Cwith a special configuration for setting up the sail blades.

Background of the Invention Wind as a source of energy is a concept that has been promoted for some time. According to one source, there is evidence which shows that windmills were in use in Babylon and Cin China as early as 2000 B.C.

0 O Despite the continued research and development in this age old technology, until the present invention, no windmill or wind turbine device has successfully appropriately O addressed some of the most important problems which have seemingly made the O harnessing of wind not economically feasible.

Vertical Axis Wind Turbines (or VAWTs) have the main rotor shaft running vertically.

The advantages of this arrangement are that the generator and/or gearbox can be placed at the bottom, near the ground, so the tower doesn't need to support it, and that the turbine doesn't need to be pointed into the wind.

Drawbacks are usually the pulsating torque produced during each revolution, and the difficulty of mounting vertical axis turbines on towers, meaning they must operate in the slower, more turbulent air flow near the ground, with lower energy extraction efficiency.

A number of these devices are comprised of a multitude of moving parts, such as rotors, stators, vanes, shields, and the like. These parts not only compromise the integrity of the machine, but also require continuous maintenance, repair and/or replacement. For such a device, which may produce only a few kilowatts of power, the costs soon begin to outweigh the benefits. Another concept widely used is to build large multi-story wind turbines capable of producing at or near the megawatt level. Two such devices are shown in U.S. Pat. No. 3,902,072 to Quinn, and U.S. Pat. No. 3,994,621 to Bogie. It is believed that these devices would cost close to $100 million to build and several hundred thousand to maintain each year.

The present invention, in its various embodiments, recognizes and addresses some of these and other problems and overcomes some limitations encountered by those skilled in the art.

Summary of the Invention It is an object of the invention to provide a wind turbine comprising a shaft having a rotational axis. arranged to be rotatably mounted to a nacelle and at least three special design blade, wherein each special design blade has a two parallel arms, a first sail blade is mounted along the two arms, a second sail blade is mounted at the end of the arms such that the first sail blade and the second blade form an angle of 75 120 degrees. The O special design blades are securely fixed to the shaft that each of the second sail blade of the special design blades defines a polygon.

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o, 0 Detail Description 0 The following descriptions and referenced drawings are for selected preferred embodiments of the present invention. Naturally, changes may be made to the Sdisclosed embodiments while still falling within the scope and spirit of the present C4 invention and the patent granted to its inventor.

As can be seen from the drawings, the basic concepts of the present invention may be embodied in many different ways. FIGS. I shows the preferred embodiment of C the wind turbine 10. The wind turbine 10 has a rotating shaft 22 attached to a nacelle 32 at one end and a number of special design blade (SDB) 42 at the other

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O The SBD has two parallel arms (44, 46) forming a framework for mounting a first O sail blade 48 and a second sail blade 50. The first sail blade 48 is mounted along the two parallel arms. The second sail blade is mounted at the end of the two parallel arms such that the first sail blade and the second sail blade form a right angle. However, the two blades can also form any angle between 75 120 degrees. Typically, each sail blade only covers substantial length of the entire arms.

A number of these SBDs is securely attached to one end of the rotating shaft.

Each of the second sail blade of the SBDs form each side of a equilateral polygon.

In one embodiment, there are four SBDs and hence they form a square. In a further embodiment, there are eight SBDs and hence they form a octagon. It is also possible to have other numbers of SBDs attached to the shaft and form different polygon.

The wind blows on the SBD and makes them turn. With this polygon configuration, it is possible to attract wind blowing from any directions, hence maximising SDB movements and transform more energy. Since the SBD are formed with simple materials, the cost of construction is greatly reduced.

In operation, the SDB turn a shaft inside the nacelle which operates the power generator.

The generator, which uses simple mechanical method to convert the rotational energy into electrical energy at a low maintenance cost. These are similar to those found in normal power stations.

The nacelle has a speed control module. The rotation speed of the shaft can vary greatly depending on the wind speed. It is possible to damage the nacelle if the rotating speed is too high. The speed control module can adjust the speed of the rotating shaft to protect the nacelle from damaging and to further utilise the energy for generating power.

The power output goes to a transformer, which converts the electricity coming out of the O generator to 240 Volts for domestic-connected systems or to the right voltage for distribution system, typically the appropriate and acceptable Voltage for grid connected ,j systems. For stand-alone systems the power is used on site or stored in batteries. For Sgrid-connected systems the power is used on site or distributed to local electricity Snetworks.

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Claims (4)

1. A wind turbine comprising a shaft having a rotational axis. arranged to be rotatably mounted to a nacelle, (ii) at least three special design blade, wherein each special design blade has a two parallel arms, a first sail blade is mounted along the two arms, a second sail blade is mounted at the end of the arms such that r the first sail blade and the second blade form an angle of 75 120 (degrees, o (iii) the special design blades are securely fixed to the shaft that each of the O second sail blade of the special design blades define a polygon. O

2. The wind turbine of claim 1 wherein the shaft has eight special design blades O securely fixed on the shaft such that the second sail blades define an octagon.

3. The wind turbine of claims 1 or 2 wherein each of the first blades only covers an substantial length of the entire length of the arms.

4. The wind turbine of any of the previous claims wherein the nacelle has a speed control module adapted to adjust the speed of the shaft. The wind turbine of any of the previous claims wherein the angle between the first blade and the second blade is a right angle.