WATER POWER PLANT HAVING A FREE-STANDING AXIS OF ROTATION

Abstract

A water power plant for the generation of electric current from a flowing medium by means of a turbine, which includes a housing around which the flow passes on an outer side, a stator of an electric generator which operates in a low-speed mode, and a rotor of the generator, which is rotatably mounted relative to the stator. The rotor includes a rotor ring with an annular surface and, starting from the rotor ring, an arrangement of inwardly extending turbine blades, thereby defining a free-standing axis of rotation. The housing defines an inlet portion with a first front-side cutting edge which delimits a circular inlet opening, from which extends an inlet-side guide surface to the rotor, and an outlet portion with an outlet opening, between which a flow path passing the rotor ring can be formed. It is provided that the inlet opening has a free inlet cross-section which is maximally as large as a cross-sectional area delimited by the rotor ring.

Claims

1-25. (canceled)

26. A water power plant for the generation of electric power from a flowing medium by means of a turbine, which features housing that medium can flow around on the outer side, a stator of an electric generator that preferably operates as a low speed rotor, and a rotor of the electric generator rotatably supported relative to the stator, and the rotor, comprising a rotor ring with an annular surface and an assembly of turbine blades extending inwardly from the rotor ring, and thereby defining a freely standing rotation axis, wherein the housing features an inlet portion with a first front-side cutting edge that delimits a circular inlet opening, from which an inlet-side guide surface extends to the rotor, and an outlet portion with an outlet opening, between which a flow path passing through the rotor ring can be formed, wherein the circular inlet opening features a free inlet cross-section, which is maximally as large as a cross-sectional area delimited by the rotor ring and the housing features a convex contour between the inlet opening and the outlet opening on the outer side.

27. The water power plant according to claim 26, wherein the free inlet cross-section of the circular inlet opening is maximally as large as the cross-sectional area that is delimited by the rotor ring minus a material cross-sectional area of the turbine blades.

28. The water power plant according to claim 26, wherein the outlet portion features a second face side cutting edge that delimits the circular outlet opening from which an outlet-side guide surface extends to the rotor, and the free inlet cross-section of the inlet opening is maximally as large as a free outlet cross-section of the outlet opening.

29. The water power plant according to claim 26, wherein the at least one front-side cutting edge features a maximum radius of 5 mm.

30. The water power plant according to claim 26, wherein the rotor can be rotated in opposite directions relative to the stator in both directions of rotation, and at least the housing is formed axis-symmetrically.

31. The water power plant according to claim 26, wherein the inner surfaces and the annular surface delimit an inner flow diameter of at least 30 cm.

32. The water power plant according to claim 26, wherein a free through-opening is provided on the axis of rotation that features a diameter of at least 10 cm.

33. The water power plant according to claim 26, wherein the turbine blades project from the rotor ring into the inlet portion and into the outlet portion.

34. The water power plant according to claim 27, wherein, the outlet portion features a second face side cutting edge that delimits the circular outlet opening from which an outlet-side guide surface extends to the rotor, and the free inlet cross-section of the inlet opening is maximally as large as a free outlet cross-section of the outlet opening.

35. The water power plant according to claim 27, wherein the at least one front-side cutting edge features a maximum radius of 5 mm.

36. The water power plant according to claim 28, wherein the at least one front-side cutting edge features a maximum radius of 5 mm.

37. The water power plant according to claim 27, wherein the rotor can be rotated in opposite directions relative to the stator in both directions of rotation, and at least the housing is formed axis-symmetrically.

38. The water power plant according to claim 28, wherein the rotor can be rotated in opposite directions relative to the stator in both directions of rotation, and at least the housing is formed axis-symmetrically.

39. The water power plant according to claim 29, wherein the rotor can be rotated in opposite directions relative to the stator in both directions of rotation, and at least the housing is formed axis-symmetrically.

40. The water power plant according to claim 27, wherein the inner surfaces and the annular surface delimit an inner flow diameter of at least 30 cm.

41. The water power plant according to claim 28, wherein the inner surfaces and the annular surface delimit an inner flow diameter of at least 30 cm.

42. The water power plant according to claim 29, wherein the inner surfaces and the annular surface delimit an inner flow diameter of at least 30 cm.

43. The water power plant according to claim 30, wherein the inner surfaces and the annular surface delimit an inner flow diameter of at least 30 cm.

44. The water power plant according to claim 27, wherein a free through-opening is provided on the axis of rotation that features a diameter of at least 10 cm.

45. The water power plant according to claim 28, wherein a free through-opening is provided on the axis of rotation that features a diameter of at least 10 cm.

Description

[0031] An exemplary embodiment of the invention is shown in the figures. Shown are:

[0032] FIG. 1 a perspective view of a water power plant according to the invention,

[0033] FIG. 2 a view of a turbine of the water power plant in direction II of FIG. 1,

[0034] FIG. 3 a sectional view of the turbine in the plane III-III of FIG. 2,

[0035] FIG. 4 an enlarged detail IV of FIG. 3,

[0036] FIG. 4a a further enlarged seal according to detail IVa of FIG. 4,

[0037] FIG. 4b an alternative embodiment of the seal,

[0038] FIG. 5 a view of a rotor of the turbine,

[0039] FIG. 6 a side view of the rotor in the direction VI of FIG. 5,

[0040] FIG. 7 a perspective view of a stator of the turbine,

[0041] FIG. 8 a perspective view of a water power installation with the water power plant according to FIG. 1,

[0042] FIG. 9 is a perspective view of an alternative embodiment of the invention water power installation with the water power plant according to FIGS. 1 and

[0043] FIG. 10 a perspective view of another alternative embodiment of water power installation with two water power plants according to FIG. 1 and a protective arrangement.

[0044] FIG. 11 a perspective view of a further alternative embodiment of the water power installation mounted on a watercraft.

[0045] FIGS. 1 and 2 show a water power plant 2 in the form of a mini power plant that features a turbine 4 with housing 6 that is held on a tubular support apparatus 8. In said case, the turbine 4 features a circular inlet opening 9 that is delimited by the housing 6 and that delimits a circular free inlet cross-section Q1 that features a diameter D1 of at least 30 cm, as can be seen in FIG. 2.

[0046] Within the housing 6, a rotor 10 of an electric generator 20 is provided. The rotor 10 features a rotor ring 12 with a cylindrical annular surface RF from which an arrangement of several turbine blades 14 projects radially inwards. The turbine blades 14 only extend so far inwardly that around a free-standing axis of rotation A defined by the rotor 10 a free passage opening 16 remains, which features a diameter DO of at least 10 cm.

[0047] As shown in FIGS. 3 and 4, the rotor 10 is rotatably mounted within an annular stator 18 that is fixedly connected to the housing 6. In said case, the rotor 10 is rotatably mounted over several rollers 22 on a stator-side inner side 24 that is formed by the stator 18 and/or the housing 6. The stator 18 and the rotor 10 thus form the electric generator 20 that is used to generate electric power from a medium flowing through the turbine 4 in the flow direction S.

[0048] The electric generator 20 of the turbine 4 operates as a low-speed rotor due to a high number of poles distributed over the circumference of the stator. In said case, the number, size, shape and angle of attack of turbine blades 14 are selected in such a way that, in the case of the applications provided for the water power plant 2, no appreciable turbulences are generated even at different flow rates.

[0049] As seen in FIG. 3, the housing 6 of the turbine 4 features a circumferential cross-section that is convexly formed on an outer side 26. As illustrated, the convex shape, for example, can be formed by two oppositely inclined face sides 28a, 28b that extend away from a first front-side cutting edge 30 and a second face side cutting edge 32.

[0050] Based on the flow direction S, the first front-side cutting edge 30 is formed on an inlet portion 31 and the second face side cutting edge 32 is formed at an outlet portion 35 of the housing 6. The first front-side cutting edge 30 delimits the circular inlet opening 9 with the free inlet cross-section Q1, and an entry-side guide surface 33 extends away from the first front-side cutting edge 30 in the direction of the rotor 10. The guide surface 33, as shown, can be designed such that it tapers towards the first front-side cutting edge 30. As an alternative to this, the guide surface 33, for example, can also be cylindrical (not shown).

[0051] The second face side cutting edge 32 of the outlet portion 35 also delimits an outlet opening 37 with a free outlet cross-section Q2 that features a diameter D2, wherein an outlet-side guide surface 39 extends away from the second face side cutting edge 32 in the direction of the rotor 10. As shown, the outlet-side guide surface 39 can also be designed such that it tapers toward the second face side cutting edge 32. As an alternative to this, however, the outlet-side guide surface 39, for example, can also be cylindrical (not shown).

[0052] In any case, the diameter D1 of the free inlet cross-section Q1 of the circular inlet opening 9 is dimensioned such that it is maximally as large as the diameter DR of the cross-sectional area QR delimited by annular area RF of the rotor ring 12. Preferably, the free inlet cross section Q1 is dimensioned in such a way that it corresponds to the resulting surface from the cross-sectional area QR of the rotor ring 12 minus a material cross-sectional area of the turbine blades 14 extending perpendicularly to the direction of flow S. In this way, only such a flow volume can flow in at the circular inlet opening 9 during operation, as can flow through the rotor 10 without substantial backwater.

[0053] Moreover, the diameter D1 of the free inlet cross-section Q1 of the circular inlet opening 9 is maximally as large as the diameter D2 of a free outlet cross-section Q2 of the outlet opening 37. In this way, a substantially backwater-free flow of a conveyed medium can be formed over an entire flow path P between the circular inlet opening 9 and the outlet opening 37, so that during the operation of the water power plant 2 an occurring backwater pressure can be reduced to a minimum.

[0054] The two cutting edges 30, 32 are preferably sharp-edged or formed with a radius as small as possible in order to be able to divide the flow body guided along the flow path P as far as possible from the rest of the medium and again converged together after passing through the water power plant 2. Preferably, the radius of the cutting edges 30, 32 is selected such that cut injuries during the assembly and in the normal use of the water power plant 2 can still be excluded, wherein the radius is at most 5 mm.

[0055] As an alternative to the illustrated cross-section of the housing 6, the housing can also be flat circumferentially on the outer side 26, in the sense of continuously smooth form. In said case, the cross-section, as shown by dashed-dotted lines, can be essentially circular in shape and axis-symmetrical. With appropriate shape and arrangement of the turbine blades 14, the turbine 4 could be operated in a directionally independent manner, i.e. from both sides. As an alternative to this, the outer side 26 could also be adapted in portions to the shape of a wing profile in order to achieve a particularly low cW value, thereby minimizing the flow resistance in a specific flow direction S or the backwater pressure on the housing 6 during operation.

[0056] As shown, particularly in FIG. 4, the turbine 4 features a coil cavity 34 that is delimited by the rotor ring 12 of the rotor 10 and the stator 18 and/or the housing 6 fixedly connected thereto. In this coil cavity 34, rotor-side magnetic-field generating means MR and stator-side magnetic-field generating means MS are arranged adjacent to each other. In the depicted embodiment of the electric generator 20, the rotor-side magnetic-field generating means MR are exemplarily formed by permanent magnets and the stator-side magnetic-field generating means MS are formed by coils.

[0057] As can be seen in FIG. 4, the two annular gaps 40A, 40B are arranged in each case between a rotor-side annular edge 36 and a stator-side annular edge 38 that can be formed both by the stator 18 and by the housing 6. Both annular gaps 40A, 40B can be sealed to the outside at least partially against the ingress of water.

[0058] In order to seal the annular gap 40A, 40B, as shown in FIGS. 4 and 4a, a lip seal 42 can be provided. As can be seen particularly from FIG. 4a, this lip seal 42, for example, can be formed by a sealing ring 44 that is held in a stator-side annular groove 46 and rests circumferentially on the rotor-side edge 36. As an alternative to this, the sealing ring 44 can also be held conversely in a rotor-side annular groove 46 and rest on the stator-side edge 38 (not shown).

[0059] FIG. 4b shows an alternative embodiment of the seal of the coil cavity 34, in which a labyrinth seal 47 is provided on the annular gap 40. For this purpose, mutually intermeshing teeth are provided on the rotor-side edge 36 and on the stator-side edge 38.

[0060] Alternatively or additionally to the use of one of the above-mentioned seals, the coil cavity 34 according to FIG. 4b can be acted upon by compressed air source 50 via a pressure line 48 with compressed air in order to prevent water ingress into the coil cavity 34.

[0061] In addition, an anti-adhesion coating can be provided on the lip seal 42 as well as on the labyrinth seal or on the edges 36, 38 in order to ensure the smallest possible friction resistance despite the seal on the annular gap 40.

[0062] In a further embodiment, the rollers 22 can be formed by lubricant-free bearing rollers, such as, for example, plastic rollers with which sealing of the annular gaps 40A, 40B can be dispensed with.

[0063] In order to avoid damage to the magnetic field generating means MR, MS in any case of water ingress into the coil cavity 34, they can additionally feature an additional protection at least in the area of the coil cavity 34. For this purpose, the coil-shaped stator-side magnetic-field generating means MS and the rotor-side magnetic-field generating means MR, as can be seen in FIGS. 5 and 6, are formed by circumferentially arranged permanent magnets, for example, sealed with epoxy resin.

[0064] As can also be seen from FIGS. 5 and 6, the rollers 22 are arranged circumferentially on the rotor ring 12 of the rotor 10. In addition or alternatively, it would also be possible to provide the rollers 22 on the stator 18 or on the housing 6 and to support them on the rotor 10 (not shown).

[0065] FIG. 7 shows the stator 18 with only a part of the preferably completely circumferentially arranged coil-shaped stator-side magnetic field generating means MS and housing part 56 that is fixedly connected to the stator 18 or formed in one piece with it. Moreover, the supporting apparatus 8 that is essentially formed by a tubular support element 52 and it thereby forms a free mounting cross-section 54 is attached to the housing part 56.

[0066] This free mounting cross-section 54 is used to hold an electrical line 58 by leading from the stator, by means of which power generated by the turbine 4 can be transmitted away. In addition, the compressed air line 48 can also be guided to the coil cavity 34 via the mounting cross-section 54 in order to connect the latter to the compressed air source 50.

[0067] FIG. 8 shows a hydroelectric installation 60 in which the water power plant 2 is connected via the support apparatus 8 to a fixing means 62. The turbine 4 here is arranged below a water level WS of a flowing body of water 64. The fixing means 62 that can be formed, for example, by a support in the form of a foundation or by a ground anchor is arranged above the turbine 4 on an embankment 66. Further means for the operation of the water power plant 2, for example, the compressed air source 50 or electrical devices E, for example, a transformer or an electrical distributor, can also be provided on the fixing means 62.

[0068] In order to be able to displace the turbine 4, for example, for maintenance, repair or cleaning purposes from the flowing water 64, a rotating and/or pivoting joint 68 can be provided between the support apparatus 8 and the fixing means 62.

[0069] As depicted, for example, for the embodiment FIG. 8, a spur 69 can be provided also on the housing 6 of the turbine 4 that protrudes, in particular, from one side of the housing 6 facing away from the supporting element 52 and for additional anchoring of the water power plant 2 on the base B of the respective water body.

[0070] FIG. 9 shows an alternative embodiment of the water power plant 60 that is operated as a stationary installation. For this purpose, the support apparatus 8 is permanently installed at a water body edge 70, for example, in a bank crest.

[0071] In both embodiments according to FIGS. 8 and 9, the fixing means 62 is arranged outside the water body at a level above the turbine, for example, on a dike 72. In this way, both the fixing means 62 and the lines 48, 58 that are routed in the support apparatus, as well as the electrical devices E can be protected from ingress of water in the event of flooding.

[0072] As can be seen from FIG. 10, in a further embodiment of the water power plant 60, two or more water power plants 2 may also be provided, for example, arranged in series or alternatively in parallel or offset with respect to one another as depicted.

[0073] Moreover, as illustrated by way of example for one of the water power plants 60 according to FIG. 10, one or more water power plants 2 may also feature a protective arrangement 74 that can be perfused with the medium. This consists, for example, of an arrangement of essentially horizontally oriented rods 76 that are arranged at an angle to the direction of flow S of the flowing water 64. In this way, floating refuse or material 78, which is approaching the relevant water power plant 2, can be deflected around the turbine 4 in order to avoid damage or contamination.

[0074] The protective arrangement 74 can thereby be attached separately to the water power plant 2, arranged behind it, for example, on the waterbed or on the shore, to withstand greater forces that are exerted, for example, by colliding with floating refuse or material 78. As an alternative to this, however, the protective arrangement 74 can also be held on the housing 6 in order to enable rapid construction and easy transport of the entire water power plant 60.

[0075] As can be seen from FIG. 11, in a further embodiment of the water power installation 60, the water power plant 2 can be attached to a watercraft 80, for example, via the rotating and/or pivot joint 68. As an alternative to the illustrated lateral attachment, the water power plant 60 can be attached alternatively or additionally to a bow or stern of the watercraft 80. In any case, the hydroelectric installation 60 can be used for charging electrochemical energy storage in the form of a battery/accumulator system 82.