Unidirectional hydro turbine with enhanced duct, blades and generator

• US 9,000,604 B2
• Filed: 04/29/2011
• Issued: 04/07/2015
• Est. Priority Date: 04/30/2010
• Status: Expired due to Fees

• Current Assignee: Clean Current Limited Partnership
• Original Assignee: Clean Current Limited Partnership
• Inventors: Sireli, Eyup Mete, Platon, Mihai C., Raychev, Milen Atanasov
• Primary Examiner(s): TA, THO DAC
• Application Number:
  US13/695,335
• Publication Number:
  US 20130043685A1
• Time in Patent Office: 1,439 Days
• Field of Search: 290/43, 290/54
• US Class Current: 290/54
• CPC Class Codes: F03B 11/02 Casings spiral or volute casings F03B3/186
• CPC Class Codes: F03B 17/061 with rotation axis substantially in flow direction
• CPC Class Codes: F05B 2240/97 on a submerged structure
• CPC Class Codes: Y02E 10/20 Hydro energy
• CPC Class Codes: Y02E 10/30 Energy from the sea, e.g. using wave energy or salinity gradient

Abstract

An apparatus is disclosed for a turbine for generating electrical power from fluid flow comprising a duct with an oblong elevation, intake hoods and vents, aft diffuser cutouts and an oblique face to optimize flow and therefore power characteristics. A unidirectional turbine generator apparatus is also disclosed comprising turbine blades with one or more raked and/or tapered sections, and optionally also with multiple beaded surface features to improve efficiency and performance of the turbine generator. A hydro turbine generator with a single-sided axial-flux magnetic generator is disclosed comprising a hybrid magnetic/anti-friction axial bearing assembly. A multiple turbine generator arrangement is also disclosed comprising multiple unidirectional turbine generators connected to a shore-based electrical distribution system.

Claims

1. A hydro turbine generator apparatus for generating electrical power from water flow, said apparatus comprising:

a rotor comprising a hub and a plurality of blades extending radially outward from said hub; and

a duct comprising an inlet end and an outlet end, an inner surface and an outer surface, and a central longitudinal axis, wherein said hub is disposed along said central longitudinal axis of said duct;

wherein α

comprises a first angle between said central longitudinal axis of said duct and a line tangential to said inner surface of said duct at said outlet end of said duct;

β

comprises a second angle between said central longitudinal axis of said duct and a line between a first point at the beginning of a flared section of said duct and a second point directly downstream of said first point and located on said inner surface of said duct at said outlet end of said duct; and

wherein the ratio of α

/β

is between 1.5 and 2.5.

2. The hydro turbine generator apparatus according to claim 1, wherein said inlet end of said duct is substantially circular in elevation, and said outlet end of said duct is oblong in elevation.

3. The hydro turbine generator apparatus according to claim 1, wherein a vertical dimension of said duct is less than a horizontal dimension of said duct.

4. The hydro turbine generator apparatus according to claim 1, wherein a ratio of a cross-sectional area of said outlet end to a cross-sectional area of said inlet end is between 1.1 and 2.1.

5. The hydro turbine generator apparatus according to claim 1, wherein at least one of said inlet and said outlet end of said duct are substantially circular, oblong, obround, elliptical or any combination thereof in elevation.

6. The hydro turbine apparatus according to claim 1, wherein a ratio of a cross-sectional area of said outlet end to a cross-sectional area of said inlet end is between 1.2 and 1.6.

7. The hydro turbine apparatus according to claim 1, wherein said hub comprises a longitudinal hole defined by at least one interior wall surface extending longitudinally through said hub.

8. The hydro turbine apparatus according to claim 1, further comprising at least one intake hood on a lateral surface of said duct, said at least one intake hood further defining at least one intake vent extending between an outer surface and an inner surface of said duct, such that a water flow is redirected from said outer surface of said duct to said inner surface.

9. The hydro turbine apparatus according to claim 1, further comprising a deviation of an edge surface at said outlet end of said duct toward said inlet end of said duct, such that at least one cut-out is defined in said edge surface at said outlet end of said duct.

10. The hydro turbine apparatus according to claim 9, comprising a first said cut-out at a top side of said edge surface at said outlet end of said duct, and a second said cut-out at a bottom side of said edge surface at said outlet end of said duct.

11. The hydro turbine apparatus according to claim 1, wherein said duct has a front face at said inlet end which is oblique in side elevation, inclining inwards towards said hub from a protruding lower front edge of said face to a recessed upper front edge of said face.

12. The hydro turbine generator apparatus according to claim 1, wherein said blades comprise at least one raked section along their span.

13. The hydro turbine generator apparatus according to any claim 1, wherein said blades comprise at least two beaded surface features along at least a portion of a low-pressure side of said blades.

14. The hydro turbine generator apparatus according to claim 1, wherein said blades each comprise a root proximal to said hub and a tip distal from said hub, and wherein said blades taper from said root towards said tip in at least one of chord thickness and chord length dimensions.

15. The hydro turbine generator apparatus according to claim 1, wherein said blades each comprise a root proximal to said hub and a tip distal from said hub, and wherein said blades comprise a radial twist extending along at least a portion of said blade between said root and said tip.

16. The hydro turbine generator apparatus according to claim 14, wherein said taper is biased towards at least one of a leading edge and a trailing edge of said hydro turbine blades.

17. The hydro turbine generator apparatus according to claims 1, additionally comprising a single-sided axial-flux magnetic generator, wherein said magnetic generator provides an axial bearing function comprising an axial magnetic attractive force which is adapted to balance at least a portion of an axial bearing load of said hydro turbine generator.

18. The hydro turbine generator according to claim 17, wherein a gap between a rotor and a stator of said magnetic generator is dynamically adjustable and is operable to dynamically adjust said axial magnetic attractive force.

19. The hydro turbine generator according to claim 1, wherein said generator is additionally operable as a turbine pump.

20. The hydro turbine generator according to claim 1, additionally comprising a permanent magnet generator, wherein a gap between a rotor and a stator of said permanent magnet generator is adapted to be fully flooded by water during immersed operation of said hydro turbine generator.

21. The hydro turbine generator according to claim 1, additionally comprising at least one anti-friction bearing, wherein said at least one anti-friction bearing is adapted to be fully flooded by water during immersed operation of said hydro turbine generator.

22. The hydro turbine generator according to claim 1, additionally comprising a single-sided axial-flux magnetic generator having a permanent magnet rotor, wherein said electrical power comprises variable voltage and frequency power signals, and wherein said generator is additionally operable to be connected to at least one other such generator and to at least one power conversion module in parallel connection for conversion of said variable voltage and frequency power signals to fixed voltage and frequency power signals.