The present invention relates to a rotary assembly of or for a fluid flow-based energy generating apparatus, such as a wind energy generating apparatus or a waterflow energy generating apparatus.

Prior-art rotary assemblies of the here above described type are associated with a number of disadvantages, which at the present are becoming increasingly more relevant with the increased adoption of renewable energy generation methods in the form of large-scale plants (e.g. wind farms) comprising significant numbers of energy generating units (e.g. wind turbines).

In particular, known rotary assemblies for fluid flow-based energy generation have been found to generate energy with sub-optimal efficiency. With such rotary assemblies, a significant portion of the captured kinetic (e.g. wind) energy is used to overcome the mechanical friction that occurs between the various moving components of such known rotary assemblies. The remaining amount of captured kinetic energy usable for generating electrical energy is thus decreased, resulting in a sub-optimal energy output.

Known fluid flow-based energy generating apparatuses are moreover known to take up a significant amount of space. Wind turbines in particular typically comprise rotor blades, that each can span 100 meter or more and are arranged at the top of tower of the wind turbine. The significant physical dimensions of such known fluid-based energy generating apparatuses have thus far limited their practical applicability at certain locations where little space is available or where the presence of such an apparatus is considered aesthetically unpleasing.

Moreover, known rotary assemblies have been found require regular maintenance, including regular repair and eventual replacement of entire components.

The objective of the present invention is to provide a rotary assembly with which at least some or others of the here above described disadvantages of known rotary assemblies are diminished or abated.

This objective is achieved with a rotary assembly of or for a fluid flow-based energy generating apparatus, the rotor assembly comprising: a base defining a stator, and a looped rotor that encloses the base and is configured to be rotatable around the base along a rotational axis of the looped rotor, wherein the base and the looped rotor are configured to induce a magnetic moment substantially parallel to a rotational axis of the looped rotor and repelling one of the base and the looped rotor relative to the other, to thereby levitate the rotor relative to the base.

In the here above described rotary assembly, the looped rotor is at all times magnetically raised from the base. Consequently, mechanical friction between the looped rotor and the base during operation of the rotary assembly is absent or at least minimised, thereby improving the operational lifetime of the rotor assembly. Moreover, when the above rotary assembly is comprised by or connected to an energy generating apparatus, energy generation with an improved degree of efficiency is achieved.

In a preferred embodiment of the rotary assembly, the base is a looped base comprising a through hole configured to receive a structural component of a fluid flow-based generating apparatus, such as an upright.

The through hole may receive, for example, a rotor hub to form a wind turbine. Alternatively, the rotor assembly according to these embodiments may be arranged an upright (e.g. a tower) of a wind turbine, with said tower extending through the through hole of the substantially looped base. As such, the energy generating capability of (existing) wind turbines may be improved. It is also conceivable that the rotary assembly is arranged around any other type of elongate (part of a) structure, including buildings, chimneys, above ground metro tubes, and the like.

In a preferred embodiment of the rotary assembly, the looped rotor comprises a flexible material, so that the looped shape of the looped rotor may be adjusted, and/or comprises a plurality of interconnected segments, wherein said interconnected segments are translatable relative to one another, such that the looped shape of the rotor may be adjusted.

In these embodiments, the rotary assembly can be easily arranged around an upright having an eccentric (i.e. non-circular shape) cross-section.

In a further preferred embodiment of the rotary assembly, the base and the looped rotor are configured to induce a further magnetic moment substantially transverse to the rotational axis of the looped rotor and repelling the one of the base and the rotor relative to the other to thereby stabilise the looped rotor relative to the base.

In the hereabove embodiments, the stability of the looped rotor relative to the base is further improved.

In a further preferred embodiment of the rotary assembly, the base comprises two halves that are disconnectable to allow the looped rotor to be arranged there between.

The construction of the rotary assembly according to the present invention results in it being relatively difficult to install this rotary assembly in comparison to rotary assemblies known in the Art. The base comprising two distinct halves that are disconnectable from one another significantly simplifies both the manufacturing and installation of the rotary assembly, because the two halves of the base can be disconnected from one another to arrange the base therebetween, after which the two halves of the base are again connected to one another with the looped rotor enclosing the base.

In a further preferred embodiment of the rotary assembly, the looped rotor comprises two parts that are disconnectable. Like in the hereabove embodiment, the looped rotor comprising two distinct parts facilitates easy manufacturing and/or installation of the rotary assembly according to the present invention.

In a further preferred embodiment of the rotary assembly, the looped rotor comprises an extension configmed to allow actuation of the looped rotor by an external force acting upon said extension. The extension is moreover preferably configured to allow actuation of the looped rotor by said external force acting upon said extension in, or parallel to, a plane of rotation of the looped rotor.

The above embodiments of the rotary assembly according to the present invention are particularly suitable to construct or assemble a novel fluid flow-based energy generating apparatus in accordance with the present invention.

In a further preferred embodiment of the rotary assembly, the rotary assembly further comprises a coil disposed at least partially around the looped rotor, and the looped rotor comprises at least one magnet disposed thereon to induce an electric current in the coil upon rotation of the looped rotor.

In a further preferred embodiment of the rotary assembly, the looped rotor comprises one or more than one rotor blade.

In a further preferred embodiment of the rotary assembly, the base comprises an electromagnet.

The objective of the present invention is moreover achieved with a fluid flow-based energy generating apparatus according to the present invention, the fluid flow-based generating apparatus comprising rotary assembly according to any one of the hereabove described embodiments.

Such a fluid flow-based energy generating apparatus may generate fluid flow-based energy with an improved degree of efficiency due to relatively low amount of mechanical friction that is generated by the rotary assembly according to the present invention.

Such a fluid flow-based energy generating apparatus preferably comprises an elongate structural component extending through the through hole of the looped base. The elongate structural component of the fluid flow-based generating apparatus may, for example, be a tower of a wind turbine. As such, the energy output of currently existing or newly build wind turbines, among other types of fluid flow-based wind energy generating apparatuses, may be improved based upon the principles of the present invention.

Moreover, the elongate structural component may be constituted by any other similarly suitable component of a structure forming the fluid flow-based energy generating apparatus. Such components may include buildings, chimneys, above ground metro tubes, and the like. Consequently, with the rotary assembly according to the present invention a fluid flow-based energy generating apparatus may be realised virtually anywhere using structural components that are already present. The invention will be elucidated here below with reference to the drawing, in which:

Fig. 1 shows a perspective view of a rotary assembly according to an embodiment of the present invention;

Fig. 2 shows a cross-sectional view of the rotary assembly of Fig. 1;

Fig. 3 shows a perspective view of a rotary assembly according to a further embodiment of the present invention;

Fig. 4 shows a cross-sectional view of the rotary assembly of Fig. 3;

Fig. 5 shows a further cross-sectional view of a rotary assembly according to the embodiment of Fig. 3 and Fig. 4;

Fig. 6 shows a cross-sectional view of a rotary assembly according to yet a further embodiment of the present invention;

Fig. 7 shows a perspective view of a rotary assembly according to the embodiment of Fig. 6;

Fig. 8 depicts a top view a rotary assembly according to yet a further embodiment;

Fig. 9 shows a perspective view of a rotary assembly of Fig. 8; and

Fig. 10A and Fig. 10B respectively depict exemplary embodiments of fluid flow-based energy generating apparatuses in accordance with the present invention.

Referring now to Fig. 1, there is depicted a rotary assembly 1 according to the present invention. The rotary assembly 1 is intended to be installable in, or at least comprised by, a fluid flow-based energy generating apparatus in the form of a wind energy generating apparatus 15. Such a fluid flow-based energy generating apparatus will be elucidated here below with reference to Fig. 10A and 10B.

The rotary assembly 1 comprises a base 3 that defines a stator. Around the base 3, there is arranged a looped rotor 5. The looped rotor 5 comprises a closed shape that encloses the base 3 defining the stator; with the base 3 being substantially arranged concentrically with the looped rotor 5. As such, the looped rotor 5 is configured to be rotatable around the base 3 along a rotational axis of the looped rotor 5 in a plane of rotation.

At least one of the base 3 and the looped rotor 5 is configured to induce at least a magnetic moment substantially parallel to a rotational axis of the looped rotor 5 and repelling the one of the base 3 and the looped rotor 5 relative to the other, to thereby levitate the looped rotor 5 relative to the base 3. This induced magnetic moment may be directed upward and/or downward with respect to the rotary assembly 1 (i.e. in both directions substantially parallel with the rotational axis of the looped rotor 5. This will be elucidated further with reference to Fig. 2.

The base 3 may moreover comprise a through hole 7. Aside from reducing material cost during production of the rotary assembly 1, the through hole 7 defines a connection means to connect the rotary assembly 1 to a-fluid flow-based generating apparatus 15 or to form such a fluid flow-based energy generating apparatus 15. Exemplary embodiments of such a fluid flow-based.

Fig. 2 depicts a cross-sectional view of the rotary assembly 1 of Fig. 1. The dashed arrows in this figure represent the opposite magnetic moments of the base 3 and the looped rotor 5. As can be discerned from this figure, at least one of the base 3 and the looped rotor 5 is configured to induce at least a magnetic moment substantially parallel to a rotational axis of the looped rotor 5. This is induced magnetic moment may be oriented downward and/or upward relative to the rotary assembly 1 and substantially parallel with rotational axis of the looped rotor 5, which is represented by the dashed arrows in Fig. 2. Consequently, one of the base 3 and the looped rotor 5 repelled relative to the other and the looped rotor 3 is levitated relative to the base 3.

As can moreover de discerned from Fig. 2, at least one of the base 3 and the looped rotor 5 is preferably configured to induce a further magnetic moment directed substantially transverse to the rotational axis of the looped rotor 5 (in both left and right directions). In Fig. 2, this is represented by (horizontal) dashed arrows. This induced sideways directed magnetic moment repels the one of the base 3 and the looped rotor 5 relative to the other. As a force to one side hence induces a counter effective force on the other side and the looped rotor 5 is thereby stabilised relative to the base 3. As such, intermediate distances between the base 3 and the looped rotor 5 can be effectively maintained in both horizontal and vertical directions.

The base 3 depicted in Fig. 2 moreover comprises a first base half 4 and a second base half 4’. In Fig. 2 these two base halves 4, 4’are indicated by the dashed line that bifurcates the base 3. The first base half 4 and the second base half 4’ are preferably disconnectable from one another, allowing for easy arrangement of the looped rotor 5 around the base 3. It is moreover conceivable that - as an alternative to the base 3 comprising a first base half 4 and a second base half 4’ - the looped rotor 5 comprises two halves (not shown) that are disconnectable from one another.

Fig. 3 shows an embodiment of the rotary assembly 1 according to the present invention having a plurality of circular or ring shaped magnets 9. The ring shaped magnets 9 are disposed at intermediate distances along substantially the entire length of the looped rotor 5, which extends through respective through holes of each of the plurality of ring shaped magnets 9. The ring shaped magnets may induce the hereabove described magnetic moments substantially parallel and/or transverse to the rotational axis of the looped rotor 5 (radial magnetization).

Fig. 4 depicts a cross-sectional view of the rotary assembly of Fig. 3. In this figure, a cross section of one of the hereabove described ring shaped magnets 9 disposed around the looped rotor 5 can be discerned. Moreover, it is shown that the base 3 comprises base magnets 2, 2’, 2”.

The base magnets 2, 2’, 2” may be permanent or electromagnets and are configured to induce the here above described magnetic moments for levitating and stabilising the looped rotor 5 relative to base, as is depicted in Fig. 2. At least one or both of the upper base magnet 2 and the lower base magnet 2” may be configured to induce the upward directed magnetic moment for levitating the looped rotor 5 as described hereabove. Moreover, the intermediate base magnet 2’ may be configured to induce the hereabove described sideways directed magnetic moment for stabilising the looped rotor 5 relative to the base 3.

Fig. 7 shows a further cross-sectional view of the rotary assembly of Fig. 3 and Fig. 4, with two of the hereabove described ring shaped magnets 9 being visible in addition to the upper base magnet 2 and the lower base magnet 2”. Fig. 5 moreover shows a coil 8 comprised by the base 3 that defines the stator. The coil 8 is disposed at least partially around the looped rotor 5. The rotary assembly 1 generates electrical energy by inducing an electric current in the coil 8 by means of a rotating magnetic field stemming from magnets (e.g. the ring shaped magnets 9) comprised by the base 3. Alternatively, the coil 8 may be comprised by the looped rotor 5 (not shown).

Fig. 7 and Fig. 8respectively show a cross-sectional view and a perspective view of a rotary assembly 1 according to a further embodiment of the present invention. As can be discerned from these figures, the looped rotor 5 comprises one or more than one extension 11 on which an external force may act to thereby actuate the looped rotor 5 and consequently generate electrical energy. This external force may, for example, be a force generated by the wind.

The respective aerodynamic shapes of each of the extensions 11 may be designed such that an optimal absorption of the wind force by each respective one of the extensions 11 is guaranteed. As such, it is emphasized here that the shape of the extensions 11 as shown in the appended figures is merely exemplary and that the extensions 11 may alternatively comprise, for example, an elongate rotor blade-like shape similar to the rotor blades of wind turbines known in the Art.

Fig. 8 shows a further embodiment of the rotary assembly 1 according to the present invention that likewise comprises a plurality of extensions 11. In contrast to the embodiments of the rotary assembly 1 depicted in the foregoing figures, the base 3 in Fig. 8 is non-annular with the through hole 7 comprised by this non-looped base 3 likewise being non-annular. Fig. 9 moreover shows that the non-looped base 3 may moreover deviate from the annular shape of the foregoing figures in a direction parallel to the rotation direction of the looped stator 5.

In the embodiments of the rotary assembly depicted in Fig. 8 and Fig. 9, the looped rotor 5 must exhibit a certain degree of flexibility for the looped rotor 5 to be able to rotate around the non-looped base 3. As such, the looped rotor 5 in Fig. 8 comprises a plurality of interconnected segments 13 that are translatable relative to one another such that the looped shape of the rotor may be adjusted. In Fig. 8, boundaries between successive interconnected segments 13 are indicated by the dashed lines. Neighbouring segments 13 may, for example, be connected to one another by means of a pivot (not shown) in a manner that is at least somewhat comparable to a roller chain or bush roller chain. Alternatively, the looped rotor 5 may comprise a material that is flexible; i.e. exhibits a degree of flexibility in a direction perpendicular to a rotational axis of the looped rotor 5 and/or a direction parallel to the rotational axis of the looped stator 5, such that the looped shape of the looped rotor 5 may be adjusted.

Fig. 10A and Fig. 10B show examples of fluid flow-based energy generating apparatuses in accordance with the present invention comprising at least one rotary assembly 1 in according to any one of the hereabove described embodiments.

Fig. 10A shows an exemplary embodiment of a fluid flow-based energy generating apparatus 15 in the form of a wind turbine 12 of a type well known in the Art. The wind turbine 12 comprises a tower 13 supporting a nacelle of the wind turbine 12. Along a vertical length of this tower 13, there is arranged a plurality of rotary assemblies 1 according to any one of the hereabove described embodiments.

Each of the rotary assemblies 1 may generate energy as described here above with reference to the foregoing figures, thereby contributing to an improved total energy output of the wind turbine 12. Rotary assemblies 1 according to the present invention may be integrated into newly build wind turbines or currently existing wind turbines may be retrofitted by means of the rotary assembly 1 according to the present invention.

Fig. 10B depicted an alternative embodiment of a fluid flow-based energy generating apparatus 15 in accordance with the present invention. In this embodiment, the fluid flow-based energy generating apparatus 15 comprises a building 14 around which one or more than one rotary assembly 1 as described hereabove is arranged. It is noted that in the exemplary embodiment of the building comprises an eccentric cross section around which the rotary assembly 1 may be arranged. However, it is entirely conceivable that the cross section of the building 14 comprises an approximately round, square or rectangular shape.

It is noted here that the scope of protection for the developments described in the present disclosure are by no means limited to any particular feature of the embodiments of either the rotary assembly 1 or the wind energy generating apparatus 15 described above and illustrated in the appended drawing. The skilled person will acknowledge, for example, that certain features disclosed herein in relation to one embodiment of the rotary assembly 1 may also be applied in another embodiment of this rotary assembly 1.

In particular, it is emphasised here that the basic principles of the herein disclosed rotary assembly 1 are applicable to all apparatuses that generate energy based on a fluid flow, which include wind energy generating apparatuses (e.g. wind turbines) and furthermore water (flow) energy generators. The scope of protection is thus exclusively determined based on the limitations of the appended independent claims, but may, in some jurisdictions, even encompass obvious alternatives for features in the independent claims. Other variations for specifically described elements, components and functionalities, that may also be embodied within the scope of the appended claims of the present disclosure, have been at least hinted at in the above embodiment description or the skilled person may be considered to be able to contemplate these variations within the range of this skilled person’s general knowledge. This exemplary reference to alternative embodiments substantiates that any limitation to any specific feature, that is not defined as a limitation in the independent claims, is unwarranted.