WO2022195611A1

WO2022195611A1 - Shrouded fluid turbine system augmented with energy feedback, control and method thereof

Info

Publication number: WO2022195611A1
Application number: PCT/IN2022/050222
Authority: WO
Inventors: Vishak Jambu NATHAN
Original assignee: Nathan Vishak Jambu
Priority date: 2021-03-17
Filing date: 2022-03-10
Publication date: 2022-09-22

Abstract

The present invention generally relates to the field of energy generation systems, more particularly to the fluid turbines. The present invention relates to a system and method for shrouded/ducted fluid turbine comprising augmented energy feedback mechanism. The ducted fluid turbine system with feedback mechanism, comprises a fluid inducer [1], a duct [13] with an inlet [2], a turbine [8], a generator [9], a diffuser [10], a power feedback controller [11] with an embedded control unit and a fluid blower [12]. Advantageously, the present invention relates to a shrouded/ducted fluid turbine with enhanced power generation via feedback mechanism. The power generated from the turbine is increased by forced induction of larger mass of fluid [air / water] into the inlet of the shroud / duct.

Description

SHROUDED FLUID TURBINE SYSTEM AUGMENTED WITH ENERGY FEEDBACK,

CONTROL AND METHOD THEREOF

FIELD OF THE INVENTION

The present invention generally relates to the field of energy generation systems, more particularly to the fluid turbines. The present invention relates to a system and method for shrouded/ducted fluid turbine comprising augmented energy feedback mechanism.

BACKGROUND OF THE INVENTION

Shrouded / ducted wind turbines were a subject of serious research until the mid 1980s. However, the relationship between the amount of material required for the duct and the area of the duct opening did not allow the shrouded wind turbines to grow in size. In addition, as the shroud increased in size, the wind drag on the shroud increased as well, requiring strong support towers. The conventional open wind turbines could be increased in size far more easily and as the technology for the same matured, the horizontal axis wind turbine with three blades came to be adopted as the industry standard.

Invelox journal paper relates to a description of a new concept in wind power and its performance evaluation. The Tnvelox Wind turbine’ used a converging / venturi duct with an omni-directional inlet on top of a tower to increase the wind speed and direct it to a turbine at the ground level. A new concept in wind power harnessing is described which significantly outperforms traditional wind turbines of the same diameter and aerodynamic characteristics under the same wind conditions and it delivers significantly higher output, at reduced cost. Its first innovative feature is the elimination of tower-mounted turbines. These large, mechanically complex turbines, and the enormous towers used to hoist them into the sky, are the hallmark of today’s wind power industry. They are also expensive, unwieldy, inefficient, and hazardous to people and wildlife. The second innovative feature of INVELOX is that it captures wind flow through an omnidirectional intake and thereby there is no need for a passive or active yaw control. Third, it accelerates the flow within a shrouded Venturi section which is subsequently expanded and released into the ambient environment through a diffuser. In addition, INVELOX provides solutions to all the major problems that have so far undermined the wind industry, such as low turbine reliability, intermittency issues and adverse environmental and radar impact. Simulating the performance of this wind delivery system is quite challenging because of the complexity of the wind delivery system and its interaction with wind at the front end and with a turbine at the back end. The objectives of the present work are to model and understand the flow field inside the INVELOX where the actual wind turbine is located as well the external flow field which not only provides the intake flow but also has to match the exhaust flow of the system. The present computations involved cases with different incoming wind directions and changes in the intake geometry. The results show that it is possible to capture, accelerate and concentrate the wind. Increased wind velocities result in significant improvement in the power output. These results led to the design of a demonstration facility which has provided actual data which verified the significantly increased power expectations. However the intake is a large nozzle, which converges to a “venturi” just before the turbine, accelerating the flow. In the present invention, the intake is the inlet is a straight or mildy widening duct, which terminates at a diffuser. The turbine is placed just at the entrance of the diffuser.

US7976270 relates to a turbine with mixers and ejectors. A Mixer/Ejector Wind/Water Turbine (“MEWT”) system is disclosed which routinely exceeds the efficiencies of prior wind/water turbines. Unique ejector concepts are used to fluid-dynamically improve many operational characteristics of conventional wind/water turbines for potential power generation improvements of 50% and above. Applicants' preferred MEWT embodiment comprises: an aerodynamically contoured turbine shroud with an inlet; a ring of stator vanes; a ring of rotating blades (i.e., an impeller) in line with the stator vanes; and a mixer/ejector pump to increase the flow volume through the turbine while rapidly mixing the low energy turbine exit flow with high energy bypass fluid flow. The MEWT can produce three or more time the power of its un-shrouded counterparts for the same frontal area, and can increase the productivity of wind farms by a factor of two or more. The same MEWT is safer and quieter providing improved wind turbine options for populated areas. However the increase in speed over the turbine is accomplished by passive fluid mechanic effects after the turbine, primarily by mixing of the flow through the turbine and the surrounding flow over the ducted turbine, thereby lowering the pressure there and increasing the wind speed through the turbine.

US20130309081 relates to a fluid turbine with rotor upwind of ringed airfoil. The present disclosure relates to a fluid turbine including a rotor and one or more ringed airfoil segments in fluid communication with a wake of the rotor. Each of the ringed airfoil segments includes a leading edge positioned co-planar with or downstream of the rotor plane as measured along the central axis. The ringed airfoil segments may include associated mixing elements. The fluid turbine may include a second ringed airfoil downstream of the one or more ringed airfoil segments. However the increase in speed over the turbine is accomplished by passive fluid mechanic effects after the turbine, primarily by the means of creating vortices behind the turbine, thereby lowering the pressure there and increasing the wind speed through the turbine.

US9932959 relates to a Shrounded wind turbine configuration with nozzle augmented diffuser. Disclosed are a system, a method and an apparatus of diffuser nozzle augmented wind turbine. In one embodiment, a method includes attaching a nozzle with a streamlined opening to a diffuser to direct an air flow into a wind turbine. In addition, the method includes increasing a wind speed approaching a set of turbine blades within a shrouded wind turbine configuration. The method also includes recirculating the air within the shroud configuration to increase an output power generated through the wind turbine. The system is composed of diffuser and nozzle integrated and non- integrated with and without a flange. In one embodiment, a method includes increasing a pressure differential of a wind turbine. However the increase in speed over the turbine is accomplished by passive fluid mechanic effects after the turbine, primarily by the means of creating vortices behind the turbine, thereby lowering the pressure there and increasing the wind speed through the turbine.

US7811048 relates to turbine-intake tower for wind energy conversion systems. A turbine-intake tower for delivering wind to a turbine has a hollow support column, an intake nozzle assembly rotatably coupled to the support column, and a tower nozzle disposed within the support column. The intake nozzle assembly is configured to receive and to accelerate wind. The tower nozzle is configured to receive the wind from the intake nozzle assembly and to further accelerate the wind received from the intake nozzle assembly for delivery to the turbine. However the intake is a large nozzle, which converges to a “venturi” just before the turbine, accelerating the flow. In the present invention, the intake is the inlet is a straight or mildy widening duct, which terminates at a diffuser. The turbine is placed just at the entrance of the diffuser.

For a given wind velocity, wind power is directly proportional to the rotor disk area of the turbine that faces the wind. The rotor area in turn scales proportionally to the square of the diameter of the rotor. As wind is “free”, with zero marginal cost, the key driver to wind turbine economics is the capital cost per unit of power generated. The need to keep the unit installed capital cost low has led to wind turbines growing in size to exploit the economies of scale with increasing rotor diameter. In the standard three blade horizontal axis wind turbines this has resulted in turbines with very large hub heights and rotor diameters. The tower and the foundation have to be designed to cater to the huge weights of hundreds of tons on top of the tower and the associated torque when the wind turbine is working and the moment due to the thrust on the rotor.

The capital cost of a modern wind turbine is very substantial and the reduction in unit capital cost has been achieved largely due to the increase in the denominator of the (Capital Cost÷ Power Generated) equation due to scaling achieved by increasing rotor diameter.

Reducing the capital cost of the turbine is a lever in achieving lower unit capital cost that has not been exploited successfully. The Diffuser Augmented Wind Turbines (DAWT), which are turbines enclosed in a shroud/duct, were an attempt to do so, but were found to be uncompetitive against just increasing the blade lengths in conventional turbines.

Generally, in machines, capital cost reductions have been achieved by increase in power density (ie power output per unit mass/size) and the resulting miniaturization of the machine.

There is no prior art for energy feedback and using “induced flow” and “entrained flow” to increase the mass flow rate through a turbine rotor to generate energy from wind or from a flowing fluid.

OBJECTS OF INVENTION

It is the primary object of the present invention to provide a shrouded/ducted fluid turbine with enhanced power generation via feedback mechanism.

It is another object of the present invention to increase the power generated from the turbine by forced induction of larger mass of fluid [air / water] into the inlet of the shroud / duct.

It is another object of the present invention to provide a Feedback Augmented Shrouded Turbine (FAST) which attempts to increase the power density of the conventional Diffuser Augmented Wind Turbines (DAWT) with forced induction which increases the mass flow rate through the machine, where energy feedback is used to increase the mass flow rate through the engine. SUMMARY OF THE INVENTION

One or more of the problems of the conventional prior art may be overcome by various embodiments of the present invention.

It is the primary aspect of the present invention to provide a ducted fluid turbine system with feedback mechanism, comprising: a fluid inducer; a duct with an inlet; a turbine; a generator; a diffuser; a power feedback controller with an embedded control unit; and a fluid blower, wherein the power produced at the generator transfers to the power feedback controller, supplying a portion of the power, to the fluid blower, wherein the fluid blower drives air for the fluid inducer as feedback, and wherein the remaining power from the power feedback controller is supplied to an external load, wherein the power feedback controller regulates the power generated from the generator and the turbine to drive the fluid blower to force induct fluid into the inlet of the duct, and wherein the inlet of the duct is placed on the top of a tower, and a duct outlet is connected to the diffuser, an outlet of the diffuser is placed at a carefully calculated level close to a ground.

It is another aspect of the present invention to provide a ducted fluid turbine system with feedback mechanism, wherein the inlet of the duct rotates to point into the wind by a fin.

It is another aspect of the present invention to provide a ducted fluid turbine system with feedback mechanism, wherein the forced induction is a positive feedback loop controlled by the embedded control unit by regulating a fraction of the total generated power to be divided between the power needed for the forced induction and the power supplied to the external load. It is another aspect of the present invention to provide a ducted fluid turbine system with feedback mechanism, wherein the power feedback controller is provided for controlling the feedback loop and for conditioning the generated power for appropriate voltage and frequency as required for supplying power to the external load.

It is another aspect of the present invention to provide a ducted fluid turbine system with feedback mechanism, wherein the turbine is mechanically connected to the fluid blower and the generator.

It is another aspect of the present invention to provide a ducted fluid turbine system with feedback mechanism, wherein the power feedback controller supplies another portion of generated power from the generator to the fluid inducer.

It is another aspect of the present invention to provide a ducted fluid turbine system with feedback mechanism, wherein the inlet comprises an air foil shape ramp at an annulus region of the fluid inducer.

It is another aspect of the present invention to provide a ducted fluid turbine system with feedback mechanism, wherein the annulus region of the fluid inducer and the inlet comprises two or more exit slits.

It is another aspect of the present invention to provide a ducted fluid turbine system with feedback mechanism, wherein the fluid inducer is in fluid communication with the fluid blower connected via a fluid flow guide pipe which is co-axial to an axis of rotation of the inlet.

It is another aspect of the present invention to provide a ducted fluid turbine system with feedback mechanism, wherein the fluid is preferably water or air.

It is another aspect of the present invention to provide a method for extracting power from a ducted fluid turbine system with feedback mechanism, comprising: transferring one portion of power from a power feedback controller to a fluid blower; transferring another portion of power from the power feedback controller to an external load; supplying the driving air for a fluid inducer as feedback by driving of the fluid blower; accelerating of the driving air along an air foil shape ramp in an annulus region of the fluid inducer; generating of a partial vacuum in an inlet of the fluid inducer and drawing in of the surrounding air into the fluid inducer where it is accelerated; drawing of the air surrounding the flow along by fluid entrainment as the flow exits the fluid inducer; exiting of the entrained air from an inlet of a duct, along with the flow from the fluid inducer transferring of the air flow via the duct to a turbine at the external load; driving of a generator by the turbine to produce electricity; and entering of the air flow into a diffuser, and discharging of the air flow back to the atmosphere.

BRIEF DESCRIPTION OF THE DRAWINGS:

So that the manner in which the features, advantages and objects of the invention, as well as others which will become apparent, may be understood in more detail, more particular description of the invention briefly summarized above may be had by reference to the embodiment thereof which is illustrated in the appended drawing, which form a part of this specification. It is to be noted, however, that the drawing illustrates only a preferred embodiment of the invention and is therefore not to be considered limiting of the invention's scope as it may admit to other equally effective embodiments.

Figure 1 illustrates the feedback augmented shrouded/ducted turbine of the present invention.

Figure 2 illustrates cross-sectional view of inducer according to an embodiment of the present invention.

Figure 3 illustrates cross-sectional view of inlet duct/shroud according to an embodiment of the present invention.

Figure 4 illustrates cross-sectional view of inducer with a blower according to another embodiment of the present invention.

Figure 5 illustrates a flowchart of components with working interrelationship (shown when applied to wind energy).

Figure 6 illustrates the feedback augmented shrouded/ducted turbine in a tower setup of the present invention. DESCRIPTION FOR DRAWINGS WITH REFERENCE NUMERALS:

[1] - Fluid Inducer

[2] - Duct / shroud inlet

[3] - Fin

[4] - Sleeve for rotation

[5] - Air supply from blower

[6] - Inlet rotation axis

[8] - Turbine

[9] - Generator

[10] - Diffuser

[11] - Power controller

[12] - Fluid Blower

[13] - Duct / shroud

[14] - Fluid flow guide pipe

[15] - Induced air

[16] - Blower air exit slit in inducer cross section [16a] - Blower air exit slit in inlet duct cross section

[17] - Entrained air

[18] - Air to turbine

[25] - Air foil shape ramp

[21] - Neck portion of Duct / shroud

[19] - Motor of blower

[30] - Grid/load

[31] - Truss

[32] - Tower legs

[35] - Duct / shroud outlet

DETAILED DESCRIPTION OF THE INVENTION

It is to be understood that the present disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The present disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The present invention generally relates to the field of energy generation systems, more particularly to the fluid turbines. The present invention gives a system and method for shrouded/ducted fluid turbine comprising augmented energy feedback mechanism.

The present invention increases wind velocity by using Power feed back to increase the mass flow rate of the wind through the turbine, by entraining the surrounding air. The higher mass flow rate through the turbine as a result of this allows the turbine to be reduced in size for a given power level.

Referring to figure 1 , the feedback augmented shrouded/ducted turbine is illustrated. A ducted fluid turbine system with feedback mechanism, comprises a fluid inducer [1], a duct [13] with an inlet [2], a turbine [8], a generator [9], a diffuser [10], a power feedback controller [11] with an embedded control unit and a fluid blower [12]. The power produced at the generator [9] transfers to the power feedback controller [11], supplying a portion of the power, to the fluid blower [12]. The fluid blower [12] drives air for the fluid inducer [1] as feedback. The remaining power from the power feedback controller [11] is supplied to an external load [30]. The power feedback controller [11] regulates the power generated from the generator [9] and the turbine [8] to drive the fluid blower [12] with a motor [19] to force induct fluid into the inlet [2] of the duct [13].

Referring to Figure 6, the feedback augmented shrouded/ducted turbine in a tower setup is illustrated. The inlet [2] of the duct [13] is placed on the top of a tower, and a duct outlet [35] is connected to the diffuser [10], an outlet of the diffuser [10] is placed at a carefully calculated level close to a ground. The tower comprises a truss [31] and two or more tower legs [32].

The inlet [2] of the duct [13] rotates to point into the wind by a fin [3]. The forced induction is a positive feedback loop controlled by the embedded control unit by regulating a fraction of the total generated power to be divided between the power needed for the forced induction and the power supplied to the external load [30]. The power feedback controller [11] is provided for controlling the feedback loop and for conditioning the generated power for appropriate voltage and frequency as required for supplying power to the external load [30]. The turbine [8] is mechanically connected to the fluid blower [12] and the generator [9]. The power feedback controller [11] supplies another portion of generated power from the generator [9] to the fluid inducer [1]. The inlet [2] comprises an air foil shape ramp [25] at an annulus region of the fluid inducer [1]. The annulus region of the fluid inducer [1] and the inlet [2] comprises two or more exit slits [16, 16a]. The fluid inducer [1] is in fluid communication with the fluid blower [12] connected via a fluid flow guide pipe [14] which is co-axial to an axis of rotation [6] of the inlet [2]. The fluid is preferably water or air. The duct [13] is a long pipe. An example is the cold air delivered all over a building by a network of pipes in a building with central a/c or split a/c. Here it is just the long vertical pipe that connects the inlet and the diffuser [10].

Referring to Figure 5, a flowchart of components with working interrelationship (shown when applied to wind energy) is illustrated. The method for extracting power from a ducted fluid turbine system with feedback mechanism comprises the following steps. One portion of power from a power feedback controller [11] is transferred to a fluid blower [12]. Another portion of power from the power feedback controller [11] is transferred to an external load [30]. The driving air is supplied for a fluid inducer [1] as feedback by driving of the fluid blower [12]. The driving air is accelerated along an air foil shape ramp [25] in an annulus region of the fluid inducer [1]. A partial vacuum is generated in an inlet of the fluid inducer [1] and the surrounding air is drawn into the fluid inducer [1] where it is accelerated. The air surrounding the flow is drawn along by fluid entrainment as the flow exits the fluid inducer [1]. The entrained air exits from an inlet [2] of a duct [13], along with the flow from the fluid inducer [1] transferring of the air flow via the duct [13] to a turbine [8] at the external load [30]. A generator [9] is drove by the turbine [8] to produce electricity. The air flow is entered into a diffuser [10], and the air flow is discharged back to the atmosphere.

Referring to Figure 2, a cross-sectional view of inducer is illustrated. Referring to Figure 3, cross- sectional view of inlet duct/shroud is illustrated. Referring to Figure 4, a cross-sectional view of inducer with a blower is illustrated. The driving air is supplied for the fluid inducer [1] as feedback by driving of the fluid blower [12] with a motor [19]. The driving air is accelerated along an air foil shape ramp [25] in an annulus region of the fluid inducer [1]. A partial vacuum is generated in an inlet of the fluid inducer [1] and the surrounding air is drawn into the fluid inducer [1] where it is accelerated. The induced air [15] surrounding the flow is drawn along by fluid entrainment as the flow exits the fluid inducer [1]. The entrained air [17] exits from an inlet [2] of a duct [13], along with the flow from the fluid inducer [1] transferring of the air flow [18] via the duct [13] to a turbine [8] at the external load [30]. Two or more blower air exit slits [16] are provided in inducer cross section. Two or more [16a] blower air exit slits are provided in inlet duct cross section. The fluid entrainment is a fluid mechanic effect. A jet of air coming out of a nozzle drags the surrounding air by by visocity and shear and hence a large amount of surrounding air is set in motion by the small jet that comes out of the nozzle. The entrained flow is the surrounding air that is dragged along by the high speed air that as it exits the inducer.

In the feedback augmented shrouded turbine, a portion of the output power (feedback power) of the turbine, by leveraging the well know fluid mechanics principles of entrained flow and induced flow, is used to “force induct” a larger mass of air than otherwise into the inlet of the shroud/duct. This forced induction of the air into the ducted turbine increases the power generated commensurately. This is analogous to the turbo charger / super charger of an internal combustion engine that uses forced induction to increase the mass flow rate through the engine to increase the power output.

The forced induction / feedback power is a positive feedback loop that is controlled by the embedded control unit. The control unit is a software program / embedded system that is a part of the power feedback controller . The control unit does this by regulating the fraction of the total generated power to be divided between the power needed for the forced induction system and the power supplied to the load. This leads to a reduction in duct inlet and allows a smaller, lighter and cheaper duct than otherwise to be placed on top of the tower, while the turbine, generator and other heavy items can be placed on the ground level. In addition, a tower for such a setup would be proportionally use less material and be cheaper than for a conventional wind turbine where the generator and turbine are placed on top of the tower.

In the present invention, a portion of the power output of the turbine by using a part of the generator output, is used to drive the blower that supplies air to the “inducer” as the “driving air”, where it is accelerated along the airfoil shaped ramp in the inducer’s annulus by “Coanda effect”. This generates a partial vacuum in the inducer inlet and draws in surrounding air (induced air) into the inducer where it is accelerated.

Alternately, instead of being driven by air supplied by the blower, the inducer could tap power supply from the generator to drive a high velocity jet fan in the inducer. As the flow exits the inducer, the air surrounding the flow is drawn along by “entrainment”, thereby increasing the mass of the air flow and serving as an “air multiplier”. The entrained air, along with the flow from the inducer exit enters the “inlet duct”, which is at the top of a tower to take advantage of the higher wind velocity further up from the ground. The flow is routed via the ducting to the turbine at the ground level. The turbine drives the generator to produce electricity. After the turbine, the flow enters the “diffuser”, where it is discharged back to the atmosphere.

The inlet duct annulus also has an airfoil ramp like the inducer, where similar Coanda effect and partial vacuum mechanism is used to increase suction, which increases the flow in the inlet and stabilizes the flow. The power produced at the generator passes to the “controller”, which routes a part of the power, to the “blower” that supplies the driving air for the inducer as “feedback”, while the remaining power is supplied to the external load.

The present invention system works on the principle of positive feedback. Due to this feedback, the turbine tends to pick up speed and the power produced at the generator increases. This allows the system generate power at a lower “cut in speed” than a conventional wind turbine. That is, the system generates power even in slower speed wind conditions in which a traditional wind turbine does not produce useable power. The controller plays a key part in controlling the feedback loop, in addition to conditioning the generated power for appropriate voltage and frequency as may be required for supplying power to the load.

Due to the much higher speed of the air flow in the shroud/duct when compared to the speed of the free stream wind, the turbine can spin at a higher speed than in a conventional wind turbine and a reducing gear system to increase the speed of the generator shaft is not necessary and the turbine is possibly directly coupled to the generator or requires far fewer and simpler gears.

The duct/shroud [13] comprises of an inlet [2], a neck portion [21] and an outlet [35]. The neck portion [21] comprises of a rotatable part above the sleeve [4] and the fixed part below the sleeve [4]. The turbine [8] is coupled to a generator [9]. The outlet [35] of duct/shroud [13] is connected to a diffuser [10]. The turbine [8] is enclosed at the junction of duct/shroud outlet [35] and diffuser [10]. The inducer [1] is placed adjacent to the ducted/shroud inlet [2]. The fin [3] is attached to the outer region of duct/shroud inlet [2]. The sleeve for rotation [4] is placed in the top portion of the supporting tower. All the parts can rotate above the sleeve [4] to point into the wind, the turning force is provided by the force generated by the fin [3] as the wind blows over it and the fluid flow pipe [14] is co-axial with the axis of rotation [6] of the inlet [2]. The fin [3] turns the opening of the inlet [2] into the wind, whereas in a conventional turbine, the wind turbine is turned into the wind by yaw motors. The inducer [1], inlet and the inlet shroud/ duct [2] are rotated about the sleeve [4] by the action of the wind over the fin / fins [3] to position the inlet mouth into the direction of the fluid flow appropriately.

In the Feedback Augmented Shrouded Turbine, the following are more beneficial over prior art

1) Dramatic decrease in duct size as a result of increased power density, making DWAT competitive with conventional wind turbines.

2) Ability to operate at lower cut in speeds, thereby generating power even in low wind conditions where a conventional wind turbine doesn’t generate power.

3) Ability to operate in higher winds than conventional turbines.

4) Larger wind speed operating range over conventional turbine leads to leads to higher capacity factor, and greater amount of power generated in a year.

5) The inlet duct mounted on top of the tower would be much smaller and lighter than otherwise and can be yawed and pointed into wind by a simple and passive fin or “wind vane” mechanism. This eliminates the need for yaw gears and motors that are used to position large turbines into the wind.

6) Much lower weights and moments need to be supported by the tower and hence will therefore be much cheaper and lighter than current turbines.

7) Lower weight of duct opening will permit pointing the duct into the wind by a simple fin via the “windvane” mechanism. Unlike conventional wind turbines, complex gearing and motors to point the duct into the wind might not be needed.

8) Mechanical gearbox between the turbine and the generator may be eliminated, increasing reliability and decreasing cost.

9) Bird safe, lower noise, no light flickering, radar interference and general environmental disturbance than current wind turbines.

Although, the invention has been described and illustrated with respect to the exemplary embodiments thereof, it should be understood by those skilled in the art that the foregoing and various other changes, omissions, and additions may be made therein and thereto, without parting from the spirit and scope of the present invention.

Claims

I CLAIM:

1. A ducted fluid turbine system with feedback mechanism, comprising: a fluid inducer [ 1 ] ; a duct [13] with an inlet [2]; a turbine [8]; a generator [9]; a diffuser [10]; a power feedback controller [11] with an embedded control unit; and a fluid blower [12], wherein the power produced at the generator [9] transfers to the power feedback controller [11], supplying a portion of the power, to the fluid blower [12], wherein the fluid blower [12] drives air for the fluid inducer [1] as feedback, and wherein the remaining power from the power feedback controller [11] is supplied to an external load [30], wherein the power feedback controller [11] regulates the power generated from the generator [9] and the turbine [8] to drive the fluid blower [12] to force induct fluid into the inlet [2] of the duct [13], and wherein the inlet [2] of the duct [13] is placed on the top of a tower, and a duct outlet [35] is connected to the diffuser [10], an outlet of the diffuser [10] is placed at a carefully calculated level close to a ground.

2. The ducted fluid turbine system with feedback mechanism as claimed in claim 1, wherein the inlet [2] of the duct [13] rotates to point into the wind by a fin [3].

3. The ducted fluid turbine system with feedback mechanism as claimed in claim 1, wherein the forced induction is a positive feedback loop controlled by the embedded control unit by regulating a fraction of the total generated power to be divided between the power needed for the forced induction and the power supplied to the external load [30].

4. The ducted fluid turbine system with feedback mechanism as claimed in claim 3, wherein the power feedback controller [11] is provided for controlling the feedback loop and for conditioning the generated power for appropriate voltage and frequency as required for supplying power to the external load [30].

5. The ducted fluid turbine system with feedback mechanism as claimed in claim 1, wherein the turbine [8] is mechanically connected to the fluid blower [12] and the generator [9].

6. The ducted fluid turbine system with feedback mechanism as claimed in claim 1, wherein the power feedback controller [11] supplies another portion of generated power from the generator [9] to the fluid inducer [1]

7. The ducted fluid turbine system with feedback mechanism as claimed in claim 1, wherein the inlet [2] comprises an air foil shape ramp [25] at an annulus region of the fluid inducer [1]

8. The ducted fluid turbine system with feedback mechanism as claimed in claim 7, wherein the annulus region of the fluid inducer [1] and the inlet [2] comprises two or more exit slits [16, 16a].

9. The ducted fluid turbine system with feedback mechanism as claimed in claim 1, wherein the fluid inducer [1] is in fluid communication with the fluid blower [12] connected via a fluid flow guide pipe [14] which is co-axial to an axis of rotation [6] of the inlet [2].

10. The ducted fluid turbine system with feedback mechanism as claimed in claim 1, wherein the fluid is preferably water or air.

11. A method for extracting power from a ducted fluid turbine system with feedback mechanism, comprising: transferring one portion of power from a power feedback controller [11] to a fluid blower

[12]; transferring another portion of power from the power feedback controller [11] to an external load [30]; supplying the driving air for a fluid inducer [1] as feedback by driving of the fluid blower

[12]; accelerating of the driving air along an air foil shape ramp [25] in an annulus region of the fluid inducer [1]; generating of a partial vacuum in an inlet of the fluid inducer [1] and drawing in of the surrounding air into the fluid inducer [1] where it is accelerated; drawing of the air surrounding the flow along by fluid entrainment as the flow exits the fluid inducer [1]; exiting of the entrained air from an inlet [2] of a duct [13], along with the flow from the fluid inducer [1] transferring of the air flow via the duct [13] to a turbine [8] at the external load [30]; driving of a generator [9] by the turbine [8] to produce electricity; and entering of the air flow into a diffuser [10], and discharging of the air flow back to the atmosphere.