Abstract:
The apparatus includes a wind turbine system for the collection of wind energy and the conversion thereof through staged-compression into highly compressed gas. The highly compressed gas is routed to a central tank, and then expanded into a plurality of concentric ring tanks, each storing gas at successively lower pressures. The cooling resulting from this expansion is utilized to cool hot compressed gas from an intermediate line of gas compressors, increasing the efficiency of the following compressors. This absorption of heat also improves the efficiency of the gas turbines driving electrical generators. The gas compressor in each wind turbine is located near ground level, and driven by a vertical shaft passing through the wind turbine support tower. One embodiment has conventional radially extending blades, and another embodiment has ducted blades to withstand higher winds. Both ground mounted and deep water adaptions for the wind turbines are disclosed.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates generally to wind turbine systems for the collection and storage of wind energy to be used for the generation of electrical energy. More specifically, the invention relates to a plurality of land or water-based wind turbines outputting compressed gas, in which the outputs are variously arranged in serial and parallel relation to provide staged compression of the gas, in which an efficient storage system for the high pressure gas outputted by the wind turbines is provided, and in which gas cooling and heating systems are in communication between certain of the wind turbines and the staged decompression storage system, enhancing the efficiencies of both the wind turbines and the air or gas turbines driven by the stored pressurized gas to produce electricity. 
     2. Description of the Prior Art 
     Applicant herein is the named inventor in U.S. Pat. No. 9,030,039 (the &#39;039 Patent), issued May 12, 2015, for a Wind Turbine And Compressed Gas Storage System For Generating Electrical Power. As shown in the &#39;039 Patent, the upper head portion of each wind turbine is pivotally mounted on a lower storage tank portion. The storage tank portion supports the head portion of the wind turbine at an elevated location to encounter wind forces effectively. The storage tank portion also serves to house a gas turbine compressor in its upper end and to store compressed gas in one or more internal tanks. 
     In this system, a plurality of such wind turbines is serially interconnected for staged compression to output high pressure compressed gas. Rows of such serially interconnected wind turbines have their outputs connected in parallel, to increase the volume of compressed gas. 
     The combined outputs of these wind turbines is fed to a reserve tank for storing the compressed gas. The reserve tank includes a plurality of concentric ring-like tanks, each tank storing compressed gas at stepped pressures, varying from the highest pressure central tank to the lowest pressure outermost ring tank. Compressed gas from the outermost ring tank is fed to one or more air turbines driving a respective electrical generator. 
     Cited by the Examiner in the prosecution of the &#39;039 Patent was US 2013/0305704 A1, now U.S. Pat. No. 8,850,808, granted to Ingersoll et al., for a Compressor And/Or Expander Device. In the &#39;808 Patent, FIG. 1 shows a Wind Farm 102 in communication with a Motor/Alternator 110, an Actuator 112, a Compressor/Expander 120, and a Storage Structure 122. The Power Grid 124 is also shown in two-way communication with the Motor/Alternator 110. FIG. 2A shows 1 st , 2 nd  and 3 rd  stage compressors serially interconnected and driven by a common hydraulic actuator. 
     Also cited in the prosecution of the &#39;039 Patent was U.S. Pat. No. 4,423,333, issued to Rossman, for a Horizontal Axis Wind Energy Conversion System With Aerodynamic Blade Pitch Control. Rossman provides a flyweight mechanism on each rotor blade to provide aerodynamic efficiency at operating wind velocities, and near constant speed and zero lift pitch of the rotor blades when rotational speeds exceed the design speed of the system. Gravity neutralization means (FIG. 6) comprised of a bevel gear and pinions couples the blades together, while the flyweight mechanism connected to the bevel gear acts to neutralize centrifugal torque on the rotor blades. 
     U.S. Pat. No. 3,806,733, is another reference cited by the Examiner in the prosecution of the &#39;039 Patent. The &#39;733 Patent shows a Wind Operated Power Generating Apparatus, including an air compressor 35 at the top of a tower 20, a pressurized air reservoir and supply tank 14, an operating tank 16, and an electric current generator 18. The supply of pressurized air inflates air cells which are attached to an endless belt. The air cells rising in a tank of fluid cause the belt to be driven upwardly, operating the electric current generator. 
     Lastly, in U.S. Pat. No. 2,454,058, cited by Applicant in the prosecution of the &#39;039 Patent, an Apparatus For Converting Intermittent Power To Continuous Power is taught. In this arrangement, the output from a wind-driven air compressor is directed underground into a “shot hole” 114 where the compressed air forces water away from the drill hole and filling the voids with compressed air. The reverse occurs when air pumping is discontinued, so as to drive the air engine 104 and generator 106 for operation during quiescent wind conditions. 
     SUMMARY OF THE INVENTION 
     The aeronautical and robust design features of the wind turbines of the present invention ensure their survivability in extremely strong wind storms. These design features include the low aspect ratio of the propeller blades, and the mechanisms to feather the propeller blades into a fully neutral position and to brake the output drive shaft of the propeller blade assembly under strong wind conditions. 
     Two embodiments of the propeller blades are disclosed, one with a plurality of conventional blades extending from a central hub, and the other a ring fan propeller having a plurality of short blades arranged in a peripheral ring assembly supported by spokes extending from a central hub. 
     Two constructions for the wind turbine towers are disclosed, one adapted for installation on the ground, and the other having special features for installation in deep water environments. This flexibility allows the wind turbine system to be installed in the most favorable wind locations, whether they be on land or over water. 
     All of the heavy components present in the nacelles at the top of prior art wind turbines have either been eliminated or moved to the base of the wind turbine tower. This reduces wind loads, eliminates the need for large construction cranes for assembly and maintenance, and places many high maintenance items at a much more convenient location for repair or replacement. 
     The apparatus includes a plurality of wind turbines, serially interconnected for staged compression to output high pressure compressed gas. A plurality of such serially interconnected lines may also have their respective outputs connected together in parallel, to increase the volume of compressed gas produced. 
     The combined output from the wind turbines is fed to a storage tank system adapted to store a large quantity of compressed gas. The storage tank includes a plurality of concentric ring-like tanks, each tank being interconnected to inner and outer adjacent tanks, each tank storing compressed gas at stepped pressures, varying from the highest pressure central tank, fed by the gas outputted from the wind turbines, to the lowest pressure outermost tank. The plurality of tanks is interconnected through pressure regulated valves to effect the stepped decompression and expansion of the contained gas. Compressed gas from the outer ring tank is fed to one or more gas turbines driving a respective electrical generator. 
     The present invention has a simplified and improved gas cooling and heating circulation system. This increases the efficiency of the higher pressure output wind turbines by drawing off hot gas outputted by a selected row of wind turbines, and circulating that hot gas through a heat exchanger line passing through the outer ring tank in the ring tank storage system. 
     Because the gas in the outer ring tank is relatively cool from the successive stages of gas expansion, this volume of stored pressurized gas is effective to cool the hot incoming gas circulated from the row of wind turbines. This cooled incoming gas is then returned to the next row of wind turbines, making their operation more efficient. 
     Through this same operation, the excessive heat from gas circulated through the heat exchanger line is effective to raise the temperature of the gas stored in the outer ring tank, making the operation of the gas turbines driving the electrical generators more efficient. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a plurality of wind turbines of a first embodiment, shown installed in a deep water environment; 
         FIG. 2  is a perspective view of a plurality of wind turbines of a second embodiment, shown installed in a deep water environment; 
         FIG. 3  is a side elevational view of the first embodiment of the wind turbine adapted for deep water mooring, showing conventional propeller blades, a support tower, a flotation tank, a ballast keel, and 3-axis couplings for the input and output gas lines; 
         FIG. 4  is a fragmentary, front elevational view of the wind turbine head of  FIG. 3 , the representation of the elevator in broken line corresponding to its position during low or no wind conditions; 
         FIG. 5  is a top plan view of the wind turbine head and flotation tank, shown in  FIG. 3 ; 
         FIG. 6  is a side elevational view of the second embodiment of the wind turbine adapted for deep water mooring, showing the ring fan propeller, a heavy duty support tower, a flotation tank, a ballast keel, and 3-axis couplings for the input and output gas lines; 
         FIG. 7  is a fragmentary, front elevational view of wind turbine head of  FIG. 6 , the representation of the elevator in broken line corresponding to its position during low or no wind conditions; 
         FIG. 8  is a top plan view of the wind turbine of  FIG. 6 ; 
         FIG. 9  is a side elevational view, comprising a fragmentary pictorial representation of the feathering and braking mechanisms for the propeller blades and the output drive shaft; 
         FIG. 10  is a side elevational view, comprising a pictorial representation of a multiplier gear train and gear box assembly; 
         FIG. 11  is a fragmentary top plan view of three of the propeller blades of the ducted ring fan propeller; 
         FIG. 12  is a fragmentary front elevational view of the propeller blades in  FIG. 11 , showing the cowling and a portion of the feathering mechanism; 
         FIG. 13  is a fragmentary side elevational view of one of the propeller blades of  FIG. 11 , showing the cowling and a portion of the feathering mechanism; 
         FIGS. 14A and 14B  comprise a schematic representation of a wind turbine system, including an array of wind turbines arranged in stages  1  through  10  and lines A through J, the array of wind turbines being interconnected in serial and parallel fashion for staged compression of gas, the high pressure gas outputted therefrom being delivered to the concentric ring tank storage system, the output from the stage  5  compressors being circulated through a heat exchanger line within the outermost ring tank and then being delivered to the input of the stage  6  compressors, outputs from the outermost ring tank being connected to respective electrical power gas turbines and generators, the graphical patterns used in  FIGS. 14A and 14B  representing respective pressures in the wind turbines and the ring tanks, according to the provided legend; 
         FIG. 15  is a representation of a wind turbine operating as an open system with ambient air from the upper head portion taken directly into an air turbine compressor, a portion of the head, tower, and base being broken away to reveal inner components; 
         FIG. 16  is a cross-sectional view of a stage  1  wind turbine configured for use in a closed system, using return air or gas from electrical power gas turbines; 
         FIG. 17  is a cross-sectional view of a stage  5  wind turbine, showing the gas supplied at approximately 1200 psi from a stage  4  turbine and being outputted at approximately 1500 psi to the heat exchanger line; 
         FIG. 18  is a cross-sectional view of a stage  10  wind turbine, showing the gas supplied at approximately 2700 psi from a stage  9  turbine and being outputted at approximately 3000 psi to the ring tank storage system; 
         FIG. 19  is a front elevational view of a 3-axis air swivel coupling; 
         FIG. 20  is a right side elevational view of a 3-axis air swivel coupling; 
         FIG. 21  is a rear elevational view of a 3-axis air swivel coupling; 
         FIG. 22  is a left side elevational view of a 3-axis air swivel coupling; and, 
         FIG. 23  is a schematic representation of a swivel joint. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The first embodiment of the wind turbine  11  is shown generally in  FIG. 1  and in  FIGS. 3-5 , inclusive. Wind turbine  11  comprises a head portion  12 , having at least two propeller blades  13  extending radially from a hub  14 . The propeller blades  13  have respective longitudinal axes, and are mounted to hub  14  for rotation about these longitudinal axes between a first rotational position where the propeller blades  13  are fully engaged with incoming wind, and a second rotational position where the propeller blades are minimally engaged with incoming wind. 
     The hub  14  is further mounted for rotation on a front end of head portion  12 , directed toward incoming wind. A first gear assembly  16 , preferably comprising a pair of bevel gears, is mounted in the head portion  12  between the front end and the rear end of head portion  12 . The first gear assembly  16  has a first shaft  17  interconnected to hub  14 , and a second shaft  18  directed vertically and downwardly. 
     One or more derricks  15  may be mounted on the upper side of head portion  12 . Structurally integrated with the wind turbine  11 , derricks  15  are useful during the initial assembly of the components comprising head portion  12 , and are also convenient for later servicing these same components. In this manner, derricks  15  substantially eliminate the need for separate tower cranes after the main components of the wind turbine have been erected. 
     A rudder  19  having lower and upper portions, is mounted on the rear end of the head portion  12 . Also included within head portion  12  is feathering and braking means  21 , responsive to the incoming wind, for maintaining propeller blades  13  in the first rotational position when the incoming winds are light and moderate, and for progressively and proportionally rotating the propeller blades  13  into the second rotational position as the incoming winds increase from moderate to strong in strength. Feathering and braking means  21  includes fin assembly  20  and an elevator  25 , pivotally attached to the trailing edge of the fin assembly  20 . The feathering and braking means  21  further applies rotational braking forces to first shaft  17  by means of disc and caliper assembly  22 , when the incoming winds are exceptionally strong. 
     Wind turbine  11  also includes a tower  23 , having an upper end  24  and a lower end  26 . Head portion  12  is rotationally mounted to upper end  24  of tower  23 , so that rudder  19  is effective to orient the front end of head portion  12  and propeller blades  13  toward any incoming wind. A gear box  27  having an input shaft  28  and an output shaft  29 , is located within the lower end  26  of tower  23 . A main shaft  31  extends vertically through tower  23 , interconnecting second shaft  18  and input shaft  28 . A drive train  32  may optionally be included, further to convert the rotational speed of main shaft  31  as needed. 
     A turbine gas compressor  33  is located below tower  23 , and is driven by output shaft  28 . Turbine gas compressor  33  has a gas inlet  34  and a gas outlet  36 . Check valves  37  are provided at the output of gas compressor  33  to prevent backflow into and through compressor  33  during a system shutdown or when a quiescent wind condition arises. 
     In the event that wind turbine  11  is installed over water, a flotation tank  38  is provided for buoyant support and vertical stability for turbine  11 , and to house turbine gas compressor  33 . Flotation tank  38  has a top end  39  and a bottom end  41 , as shown most clearly in  FIG. 3 . The top end  39  of flotation tank  38  is attached to lower end  26  of tower  23 . Also provided is a ballast keel  42 , having a vertical axis  43 , an upper portion  44 , and a lower portion  46 . The vertical axis  43  of ballast keel  42  is aligned with the longitudinal axis of tower  23 , and the upper portion  44  of keel  42  is attached to the bottom end  41  of flotation tank  38 . To provide further stability in orientation and location for the wind turbine  11 , a plurality of mooring cables  47  is provided, having respective upper ends attached to lower portion  46  of ballast keel  42 . 
     Owing to the inevitability of some movement of wind turbine  11  over open water, a 3-axis coupling  48  is provided. A coupling  48  is included at least at the gas outlet  36  of turbine gas compressor  33 . If the wind turbine  11  is one of the stage  2  through stage  10  turbines, and therefore has a gas inlet  34  interconnected to the gas outlet  36  of a previous stage compressor  33 , a coupling  48  will also be included at the gas inlet  34 . An example of such a wind turbine  11  is shown in  FIG. 3 . 
     Each 3-axis coupling  48  comprises a plurality of curved pipe sections  49  joined by respective swivel joints  51 . Each swivel joint  51  includes means for maintaining a gas-tight seal within a respective swivel joint  51 , irrespective of the position or rotation of pipe sections  49 . In the example shown in  FIG. 23 , groups of o-rings  52  are provided around the top, bottom, and side edges of the end flange  53  of a pipe section  49 . Ceramic or rubber gaskets may also be considered structural equivalents of these o-rings, for purposes of the present disclosure. 
     It is apparent that the present design lowers all heavy components of the wind turbines  11 , aside from the head portion  12  and its associated components, to the base or lower end  26  of the tower  23  of each wind turbine  11 . These heavy components include the turbine gas compressor  33 , the gear box  27 , the drive train  32 , and all input and output gas plumbing associated with the turbine gas compressor  33 . This relocation of the heavy components to a lower position within the wind turbine  11 , speeds up construction and makes future maintenance operations much simpler and safer. 
     In the event that wind turbine  11  is installed over land, a very similar construction is employed to that just described. For example, in  FIG. 15 , a stage  1  wind turbine adapted for land installation is shown. In this arrangement a tower base  54  is provided, immediately below the lower end  26  of the tower  23 . The tower base  54  may be located partially underground, and preferably includes access doors or panels (not shown), for ready access to the turbine gas compressor  33  and its associated gas plumbing. 
     The wind turbine  11  shown in  FIG. 15  is termed a stage  1  wind turbine, as its turbine gas compressor  33  has a gas inlet  34  in communication with the ambient air. This arrangement is also termed an “open” system, to be contrasted to a “closed system” described below. A stage  1  wind turbine  11  compresses ambient air sufficiently so that its air outputted through gas outlet  36  is at approximately 300 psi. This outputted air, in turn, is fed to the gas inlet  34  of a stage  2  turbine gas compressor  33 . 
     Making particular reference to  FIG. 14A , it can be seen that lines A-J of the stage  1  wind turbines  11  have their outputs directed to a respective stage  2  wind turbine  11 . The serial interconnections of stage  1  through stage  10  wind turbines results in successive increases of approximately 300 psi for each stage. This staged air compression results in an output of approximately 3000 psi from the plurality of stage  10  wind turbines  11 , toward the top of  FIG. 14A . The arrangement of wind turbines  11  in  FIG. 14A  comprises a “closed system”, as the air or gas fed to the inlets of the stage  1  wind turbines comes from a return air line  56 . As will be seen in  FIG. 14B , return air line  56  is connected to the discharge of gas turbines  57 . In other words, after the compressed gas is utilized to drive gas turbines  57 , it is returned to the stage  1  wind turbines, to be reused. Air or gas used in a closed system may be conditioned and filtered, to reduce moisture and contaminants, for example. Air used in an “open system” is simply used one time by the system, and discharged to the ambient air from gas turbines  57 . 
     Turning now to  FIG. 16 , another type of stage  1  wind turbine  11  is shown. It should be noted that the gas inlet  34  is being fed gas at 15 psi from return line  56 . This is the type of stage  1  wind turbine  11  which would be employed in the closed system, shown in  FIG. 14A . The turbine gas compressor  33  delivers gas at approximately 300 psi through gas outlet  36  to a stage  2  wind turbine.  FIG. 17  shows a stage  5  wind turbine  11 . The construction of this wind turbine  11  is identical to that of the stage  1  wind turbine, with the exception that its gas inlet  34  is receiving gas at approximately 1200 psi, and its gas outlet  36  is outputting gas at approximately 1500 psi. FIG.  18  shows a stage  10  wind turbine  11 . The construction of this wind turbine  11  is identical to that of the stage  1 - 9  wind turbines  11 , with the exception that its gas inlet  34  is receiving gas at approximately 2700 psi, and its gas outlet  36  is outputting gas at approximately 3000 psi. 
     The combined output from the wind turbines  11  is fed through a high pressure output line  58  to a storage tank system  59  adapted to store a large quantity of compressed gas. The storage tank system  59  includes a plurality of concentric ring-like tanks, each tank being interconnected to inner and outer adjacent tanks through pressure actuated transfer valves  60 . The actuating or threshold pressure of the pressure actuated valves  60  is such that each tank stores compressed gas at a respective stepped pressure, varying from the highest pressure central tank, fed by the gas outputted from the last stage of the wind turbines, to the lowest pressure outermost tank  61 . In the respects described so far, the construction and operation of the storage tank system  59  is identical to that disclosed in U.S. Pat. No. 9,030,039. 
     However, the present invention has a simplified and improved gas cooling and heating circulation system from that shown in the &#39;039 Patent. The outermost ring tank  61  includes a heat exchanger line  62 , provided with a plurality of peripheral fins  63  to enhance the transfer of heat. Heat exchanger line  62  has an inlet connected to a first cooling line  64  and an outlet connected to a second cooling line  66 . First cooling line  64  is preferably connected to the gas outputted by the stage  5  wind turbines, in the first plurality  67  of wind turbines comprising all of the wind turbines in stages  1 - 5  , inclusive. Second cooling line  66  is connected to the gas inputted into the stage  6  wind turbines, in the second plurality  68  of wind turbines comprising all of the wind turbines in stages  6 - 10 , inclusive. See,  FIGS. 14A and 14B . 
     It should be noted that the heat exchanger line  62  could be interconnected between, for example, stages  3  and  4 , or stages  7  and  8 . Or, there could be more than one heat exchanger line in a system. 
     Heat exchanger line  62  passes through outermost ring tank  61 , and is effective to transfer heat from gas outputted by from the outputs of the stage  5  wind turbines within the first plurality  67  of wind turbines  11  into the gas contained within outermost ring tank  61 , and to return cooled gas passing through said second cooling line to the inputs of the stage  6  wind turbines within the second plurality  68  of wind turbines  11 . 
     This increases the efficiency of the higher pressure output wind turbines  11  by drawing off hot gas outputted by a selected row of wind turbines, and circulating that hot gas through heat exchanger line  62  passing through the outermost ring tank  61  in the storage tank system  59 . Because the gas in the outermost ring tank  61  is relatively cool from the successive stages of gas expansion, this contained volume of stored pressurized gas is effective to cool the hot incoming gas circulated from the stage  5  row of wind turbines  11 . This cooled gas is then returned to the stage  6  row of wind turbines  11 , making their operation more efficient. 
     Through this heat exchange process, the excessive heat from gas circulated through the heat exchanger line  62  is effective to raise the temperature of the gas stored in the outermost ring tank  61 . Compressed gas from the outermost ring tank  61  is fed to one or more gas turbines  57  driving a respective electrical generator  69  connected to a transformer  71 . By utilizing the excessive heat generated by the first plurality  67  of wind turbines  11  and raising the temperature of the gas within the outermost ring tank  61 , the operation of the gas turbines  57  driving the electrical generators  69  is made more efficient. 
     A second embodiment of the wind turbine  11  is shown generally in  FIG. 2 , and more specifically in  FIGS. 6-8 , inclusive and in  FIGS. 11-13 , inclusive. This second embodiment shares many features with the first embodiment described above, but includes a head portion  12  having a different apparatus for converting incoming wind to rotational forces for driving its turbine gas compressor  33 . 
     Head portion  12  of the second embodiment has a ring fan propeller  72  attached to shaft  17 . Ring fan propeller  72  comprises a peripheral outer ring or cowling  73 , a concentric inner ring or cowling  74 , and a central hub  76 . Ring fan propeller  72  further has a plurality of support arms  77  extending radially from hub  76  to inner ring  74 , and a plurality of propeller blades  78  positioned transversely between inner ring  74  and outer ring  73 . Each blade  78  has an leading edge  79  and a trailing edge  81 . The inner and outer rings serve to redirect and compress air at the leading edges  79  of the propeller blades  78  in order to drive them more effectively, as well as to create a vacuum at the trailing edges  81  in order to accelerate the exhaust of air passing through the propeller blades  78 . Each blade  78  is pivotally mounted adjacent its leading edge  79  for rotation about a shaft  82  having an axis transverse to a respective blade  78 . 
     Ring fan propeller  72  further includes means  83  to rotate propeller blades  78  from a first rotational position where the blades  78  are fully engaged with incoming wind, and a second rotational position where the blades  78  are minimally engaged with incoming wind. More specifically, means  83  comprises a rack and pinion  84 , primary tension bars  86 , bevel gear assembly  87 , and secondary tension bars  88 . Rack and pinion  84  is slidably and rotationally mounted over first shaft  17 , so that the entire ring fan propeller  72  can rotate while allowing blades  78  to be appropriately adjusted by movement of the remainder of the feathering and braking means  21  in response to movement of elevator  25 . In this manner, each of the propeller blades  78  may be feathered to a fully neutral position in reaction to very high wind velocity. 
     It will be appreciated, then, that I have disclosed an improved wind turbine and a compressed gas storage system capable of being located on land or over water, which apparatus makes wind energy storable and dispatchable, making possible the supply of base load and peak load requirements, and overcoming the intermittence of wind, one of the main problems associated with the generation of electricity by wind power.