WO2016027010A1

WO2016027010A1 - Synchronous electromagnetic motor or generator having a plurality of air gaps and diagonal magnetic flux

Info

Publication number: WO2016027010A1
Application number: PCT/FR2015/000168
Authority: WO
Inventors: Romain RAVAUD
Original assignee: Whylot Sas
Priority date: 2014-08-19
Filing date: 2015-07-30
Publication date: 2016-02-25

Abstract

The present invention relates to a motor (1) or generator including: a rotor (2) having a body (2a) in the form of a disk, secured to at least one drive shaft (3, 3a); at least one stator (4); at least one permanent magnet (5, 5a) supported by the rotor (2); and at least one related winding (6, 6a, 6b, 6c) supported by the stator (4). The winding (6, 6a, 6b, 6c) is positioned such as to create a magnetic flux on said at least one magnet (5, 5a) when supplied with electricity or vice versa. The rotor (2) includes at least two magnets (5, 5a) extending in two different directions. At least one of the magnets extends such as to project from and revolve around the body (2a), making an angle different from 0° and from 90°. A winding (6, 6a, 6b, 6c) is provided on each side of each magnet (5, 5a).

Description

"Synchronous electromagnetic motor or generator with multiple air gaps and diagonal magnetic flux"

The present invention relates to a synchronous electromagnetic motor or generator with several air gaps and diagonal magnetic flux, this flux being different from an axial or radial flow or a combination of these two types of flow.

According to the state of the art, a conventional motor embodiment is composed of at least one rotor forming its rotating element and at least one stator forming its fixed element. The rotor may comprise at least one series of permanent magnets and the stator may comprise at least one series of coils.

When the series or series of windings are electrically powered, the rotor which is attached to the motor drive shaft is subjected to a torque resulting from the magnetic field thus created. Depending on the direction of the magnetic flux created, a motor is referred to as axial, radial or transverse flow.

For a generator, it is the rotation of the rotor that creates an induced current in the series of coils.

For an axial flow motor, the or each series of magnets has a thick arc shape. Magnets are said to axial flow because their magnetic field is orthogonal to the plane of the arc of the disc forming the rotor body. The center of the arc goes through the drive shaft of the motor or electromagnetic generator.

There are also synchronous motors with radial magnetic flux directed towards the center of the motor and synchronous motors with transverse flux. A transverse flow motor has the following configuration: a stator with a single axial coil with several magnetic circuits, stirrups, orthoradial orientation and overlapping the winding, the rotor retaining its role of looping the magnetic flux but having magnets at the new configuration of the stator and winding brackets.

For these two types of synchronous motor, it has also been developed a multi-gap structure, that is to say having at least one stator between two rotors or at least one rotor between two stators. This increases the torque delivered by the engine but has the disadvantage of complicating the construction and size of the engine.

More and more synchronous motors must fulfill the requirement to have the smallest possible footprint while providing the highest power possible. It has therefore also been proposed motors combining an axial flow with a radial flow.

WO / 2011059162 discloses an axial flow permanent magnet motor or generator which combines an axial flow mode with a radial flow mode. This motor or generator comprises a first and a second rotor each comprising at least one magnet, said magnets being installed in opposite directions, a first and a second stator each comprising a coil at each end of a core, face to face, said core comprising a fixing unit connected to its central part and fixed to an external anchoring support to interpose between the first rotor and the second rotor.

The engine or generator according to this document also comprises a yoke which is spaced apart from the magnets installed in the first and second rotors and which is connected to the first and second rotors from the inside to form a magnetic flux circuit.

Therefore, such an engine or generator combines the advantages of an axial flow and a radial flow. In addition, by having two stators between the magnets, the torque in a given place can be doubled, which gives a motor or a high efficiency generator.

However, it is desirable to be able to further increase the torque produced by a synchronous motor while not noticeably increasing its price or its bulk.

US-A-2004/150289 or US-A-5 886 550 discloses an electromagnetic motor or generator comprising a rotor with a body in the form of a disc secured to at least one median drive shaft, at least one stator, at least one permanent magnet being carried by the rotor and at least one associated winding being carried by said at least one stator, an air gap being defined between said at least one magnet and said at least one winding, said at least one winding being positioned to create a magnetic flux on said at least one magnet when electrically powered or conversely, the rotor comprising at least two magnets extending in two different directions, at least one of which extends in projection and revolution of the rotor body while making with the body an angle different from 0 ° and 90 °, a winding being provided for each magnet, said at least two magnets being distributed all around the rotor body leaving a gap between them.

In these documents, the windings are outside the distribution of said at least two magnets arranged around the rotor body and do not penetrate between said at least two magnets. It follows a lack of compactness of such engine or generator object of these documents.

WO-A-00/70725 discloses an engine comprising two parallel branches forming an angle of 180 ° between them since extending in the opposite direction, each carrying a magnet. A winding is interposed between the two branches. In such an engine, the branches do not form an angle of 0 to 90 ° between them starting from the same central core and are not in revolution around the body of a rotor which is not in the form of a disk. It follows that such an engine or generator that does not have a rotor in the form of a disk is not compacted optimally.

The problem underlying the present invention is to design a motor or generator comprising a rotor in the form of a disk that can deliver a magnetic flux during its operation not derived from an axial or radial flow or a combination of these two flows, this magnetic flux to significantly increase the torque provided by the engine or the energy delivered by the generator while maintaining a high compactness to the engine or the generator, the engine or generator that can withstand a speed of high rotation of the rotor.

For this purpose, there is provided according to the invention an electromagnetic motor or generator comprising a rotor with a body in the form of a disc secured to at least one median drive shaft, at least one stator, a gap being defined between the rotor and said at least one stator, at least one permanent magnet being carried by the rotor and at least one associated winding being carried by said at least one stator, said at least one winding being positioned to create a magnetic flux on said at least one a magnet when electrically energized or vice versa, the rotor comprising at least two magnets extending in two different directions, at least one of which extends in projection and revolution of the rotor body while making with the body an angle different from 0 ° and 90 °, a winding being provided on each side of each magnet, said at least two magnets being distributed all around the rotor body leaving a gap between them, characterized in that a winding is housed in the interval, the magnetic flux created by the coil exerted on the two magnets surrounding it.

Such an electric motor or generator can not be qualified as a motor or generator with radial flow or axial flow or even combined radial and axial flow. The flow created is rather similar to a diagonal flow according to the positioning of the magnets, especially when they are positioned in axial section in a star-shaped configuration. It is thus possible to have a motor or generator with multiple air gaps with a power multiplied by the number of magnets forming branches of different direction on the rotor.

As a coil is housed in each gap between two magnets, the magnetic flux created by the coil acting on the two magnets, the coils therefore extend in the largest possible space and exploits the free space of the interval between two magnets. This increases the efficiency of the engine and makes the engine significantly more compact than when the windings are arranged outside, as is shown by the state of the art closest.

Advantageously, said at least two magnets are inclined relative to each other in axial section of the rotor. This makes it possible to maintain a narrowing gap as one moves closer to the rotor and to ensure that the magnets take up a minimum of space by exploiting all the space surrounding the portion of the rotor that carries the magnets.

Advantageously, said at least two magnets are distributed around the body in the form of rotor disk leaving an interval between them in which is housed a coil, the magnetic flux created by the coil acting on the two magnets surrounding it or conversely for a generator. This results in a uniform distribution of the magnets all around the rotor body.

Advantageously, each winding has a specific shape at its associated interval. This makes it possible to exploit the associated interval as much as possible. Advantageously, each winding has a pointed shape narrowing towards the portion of the rotor separating two adjacent magnets. Thus, the gap between two magnets is almost completely filled by a coil, resulting in space saving and obtaining a compact configuration motor or generator.

Advantageously, said at least two magnets define in axial section of the rotor a star shape. The star shape is preferred since it makes it possible to exploit all the surrounding space all around the portion of the rotor carrying the magnets. The magnets are not so superimposed or aligned but connected to each other to the portion of the rotor carrying them, which provides a saving of space and helps to obtain a compact configuration engine or generator.

Advantageously, the star shape comprises from two to ten branches, each branch carrying a magnet.

Advantageously, the windings are secured to a carrier structure forming a stator. This helps support the windings and compactness of the stator, as well as its rigidity.

Advantageously, at least two windings are carried by a common structure. This assists in supporting and maintaining the windings so that they are properly inserted into their respective gaps between two adjacent magnets of the rotor and remain in place within this range without the possibility of shifting.

Advantageously, the structure common to said at least two coils is connected to the carrier structure, which reinforces the holding of the coils in position.

Advantageously, said at least magnets are brought towards the periphery of the rotor body by forming a first set of magnets and coils.

Advantageously, the motor or the generator has at least one second set of magnets and coils, the second set of magnets and winding being closer to the drive shaft than the first set. With such an arrangement, for the same size of the stator, it can be delivered at least twice as much torque or n times stronger when the engine comprises n sets. These at least two sets can operate commonly or alternatively. For example, as an example of alternative operation, for a motor developing a high torque, an external positioning of an assembly is advantageous while for a motor rotating at high speed, a more internal positioning of a set is more appropriate, which it makes it possible to reduce the centrifugal force applying to the magnets carried by the assemblies and to avoid their detachment.

Other features, objects and advantages of the present invention will appear on reading the detailed description which follows and with reference to the appended drawings given by way of non-limiting examples and in which:

FIG. 1 is a schematic representation of an axial section of a non-axial or radial synchronous motor or generator according to a first embodiment of the present invention,

FIG. 2 is a diagrammatic representation of an axial section of a non-axial or radial synchronous motor or generator according to a second embodiment of the present invention.

The figures are given by way of examples and are not limiting of the invention. They constitute schematic representations of principle intended to facilitate the understanding of the invention and are not necessarily at the scale of practical applications. In particular, the dimensions of the different pieces are not representative of reality.

More precisely, the number of branches of the axial star section shown in FIGS. 1 and 2 is not limiting. In addition, the windings shown are not necessarily connected to each other or to each other as illustrated. Different forms of structure carrying windings have been shown on the right and left in the figure: this is not necessarily the case, these bearing structures may be similar to left and right, which is the preferred embodiment. These different carrier structures may constitute alternative embodiments for maintaining the windings.

Referring to FIGS. 1 and 2, in general, a motor 1 or an electromagnetic generator comprises a rotor 2 in the form of a disk secured to at least one median drive shaft 3, 3a and at least one a stator 4. The rotor 2 comprises a body 2a which forms the disk extending perpendicular to the drive shaft 3, 3a being integral thereto.

In Figures 1 and 2, there are two drive shafts 3 and 3a integral with the rotation of the rotor 2, the first of these two shafts 3 being disposed on one side of the stator 4 while the second of these shafts 3a is disposed on the other side of the stator 4. This is not limiting and there may be only one drive shaft integral with the rotation of the rotor 2.

A rolling bearing 10, 10a fixed to the stator 4 surrounds each drive shaft 3, 3a in order to allow it to rotate relative to the stator 4.

At least one permanent magnet 5, 5a is carried by the rotor 2 and at least one associated winding 6, 6a, 6b, 6c is carried by said at least one stator 4, an air gap being defined between said at least one magnet 5, 5a and said at least one winding 6, 6a, 6b, 6c. Said at least one winding 6, 6a, 6b, 6c is positioned to create a magnetic flux on said at least one magnet 6, 6a, 6b, 6c. For a generator, it is the rotation of the rotor 2 and said at least one magnet 5, 5a which creates a current induced in the windings 6, 6a, 6b, 6c.

In Figures 1 and 2, only two magnets are shown by being inserted into a form 11 housing forming part of the rotor 2 being indicated by references 5 and 5a. These references, however, apply to all permanent magnets illustrated in these figures which can be housed in a respective form. The same applies to the windings and their references 6, 6a which are valid for all windings. References 6b, 6c relate to specific windings which will be further detailed.

In Figures 1 and 2, it is visible that in the illustrated embodiments, the magnets 5, 5a are carried by a respective branch of which only two are referenced 11. The magnets 5, 5a can be encapsulated in a resin or other binder to be secured respectively with their branch 11. In one embodiment of the present invention, it is also possible that the magnets occupy the entire width of the shape carrying them respectively.

According to the present invention, the rotor 2 comprises at least two magnets 5, 5a extending in two different directions, at least one of which extends in projection and in revolution of the body 2a of the rotor 2 while making with the body 2a an angle different from 0 ° and 90 °, a winding 6, 6a, 6b, 6c being provided on each side of each magnet 5, 5a.

The engine or the generator is said to have several air gaps with a succession of different diagonal magnetic fluxes for most of a radial or axial magnetic flux.

The magnets 5, 5a may be of revolution being continuous around the rotor 2 as well as the windings 6, 6a, 6b, 6c, the magnets 5, 5a can then be substantially cylindrical. In another embodiment of the invention, a magnet 5 or 5a may consist of a series of magnets forming a distribution of magnets in revolution around the rotor 2, mainly of its body 2a.

Said at least two magnets 5, 5a are advantageously inclined with respect to one another in axial section of the rotor 2. It is possible that one of the magnets 5 is in the extension of the body of the rotor 2 or included in the body of the rotor 2 while the other forms an angle with the rotor body always in axial section of the rotor 2.

In a preferred form of the present invention, shown in FIG. 1, said at least two magnets 5, 5a are distributed all around the disk formed by the body 2a of the rotor 2, leaving a gap between them in which is housed a coil 6 , 6a, 6b, 6c, the magnetic flux created by the coil 6, 6a, 6b, 6c acting on the two magnets 5, 5a surrounding it or conversely for the generator.

Preferably, as shown in Figure 1, this distribution can be uniform and symmetrical leaving the same gap between each magnet 5, 5a and its immediate neighbor.

Each winding 6, 6a, 6b, 6c has a shape specific to its associated interval. As the magnets 5, 5a can extend by having an inclination, advantageously axial, between them and therefore extending in divergent directions away from each other, the further away the rotor 2, each coil 6, 6a, 6b, 6c has a pointed shape 7 narrowing towards the portion of the rotor 2 separating two magnets 5, 5a adjacent.

In a preferred and particularly advantageous embodiment of the present invention, always shown in FIG. 1, said at least two magnets 5, 5a define in axial section of the rotor 2 a starry shape. This star shape has at least two branches, each branch having a respective magnet 5, 5a.

Thus the star-shaped axial section of the rotor 2 can comprise two to n branches, n being a natural number greater than two, each branch carrying a magnet or a succession of magnets around the rotor 2. The number n is advantageously between three and twenty.

FIG. 2 shows an alternative embodiment to that of FIG. 2. In this embodiment, said at least two magnets 5, 5a are non-uniformly distributed around the disk constituted by the body 2a of the rotor 2, leaving a interval between them in which is housed a coil 6, 6a, 6b, 6c, the magnetic flux created by the coil 6, 6a, 6b, 6c exerted on the two magnets 5, 5a surrounding or conversely for the generator. There is therefore a portion of the star directed towards the drive shaft 3, 3a which has no branches.

Referring again to Figures 1 and 2, at least a portion of the windings 6, 6a, 6b, 6c can be secured to a carrier structure 8 forming a stator 4, in particular by defining its inner contour. The carrier structure 8 may advantageously be in the form of a housing containing the windings 6, 6a, 6b, 6c and surrounding at least partially at a distance the outer contour of the body 2a of the rotor 2, in particular its outer periphery farthest from the drive shaft 3, 3a.

At least two coils 6b, 6c can also be carried by a common structure 9. In this case, the common structure 9 to said at least two coils 6b, 6c can advantageously be connected to the carrier structure 8.

In Figures 1 and 2, magnetization arrows are incorporated in the magnets. It is possible to reverse the direction of the arrows and even arrange the magnets so that the arrows are oriented differently.

Said at least two magnets 5, 5a can be brought towards the outer periphery of the disk-shaped body 2a of the rotor 2, that is to say its outermost portion furthest from the drive shaft 3, 3a. In this case, the periphery of the rotor 2 with said at least two magnets 5, 5a and the windings 6, 6a, 6b, 6c form a first assembly in revolution of magnets 5, 5a and coils 6, 6a, 6b, 6c . The engine 1 or the generator may have at least a second set of magnets and coils, the second set of magnets and winding being closer to the drive shaft 3, 3a than the first set. The windings 6, 6a, 6b, 6c of each of these assemblies can be powered separately in order to provide the motor with a regulation of its power.

A conventional winding 6, 6a, 6b, 6c may consist of a good conductor wire wound on a support means advantageously flexible and elastically deformable. The coils 6, 6a, 6b, 6c can also be embedded in any insulating binder, for example a resin, to ensure good electromagnetic insulation thereof.

A non-limiting embodiment of a winding or windings for an engine or a generator may comprise one or more windings in the form of a rigid branch, for example three rigid branches, which corresponds to the use of a three-phase current. This or these rigid branches are advantageously in one piece.

Advantageously, the motor or the electromagnetic generator according to the present invention can be polyphase. In this case, it advantageously has at least one winding per phase of current.

The invention is in no way limited to the described and illustrated embodiments which have been given by way of example only.

Claims

1. Motor (1) or electromagnetic generator comprising a rotor (2) with a body (2a) in the form of a disc integral with at least one median drive shaft (3, 3a), at least one stator (4) ), at least one permanent magnet (5, 5a) being carried by the rotor (2) and at least one associated winding (6, 6a, 6b, 6c) being carried by said at least one stator (4), an air gap being defined between said at least one magnet (5, 5a) and said at least one coil (6, 6a, 6b, 6c), said at least one coil (6, 6a, 6b, 6c) being positioned to create a magnetic flux on said at least one magnet (5, 5a) when electrically energized or vice versa, the rotor (2) comprising at least two magnets (5, 5a) extending in two different directions, at least one of which extends in projection and revolution of the body (2a) of the rotor (2) making with the body (2a) an angle other than 0 ° and 90 °, a winding (6, 6a, 6b, 6c) being provided on each side of each magnet (5 , 5a), the s said at least two magnets (5, 5a) being distributed all around the body (2a) of the rotor (2) leaving a gap between them, characterized in that a coil (6, 6a, 6b, 6c) is housed in the interval, the magnetic flux created by the coil (6, 6a, 6b, 6c) exerted on the two magnets (5, 5a) surrounding it.

2. Motor (1) or generator according to the preceding claim, wherein said at least two magnets (5, 5a) are inclined relative to each other.

3. Motor (1) or generator according to the preceding claim, wherein each winding (6, 6a, 6b, 6c) has a shape specific to its associated range.

4. Motor (1) or generator according to the preceding claim, wherein each winding (6, 6a, 6b, 6c) has a pointed shape (7) narrowing towards the portion of the rotor (2) separating two magnets (5, 5a) adjacent.

5. Motor (1) or generator according to any one of the two preceding claims, wherein said at least two magnets (5, 5a) define in axial section of the rotor (2) a star shape.

6. Engine (1) or generator according to the preceding claim, wherein the star shape comprises two to n branches, n being a natural integer greater than 2, each branch carrying a magnet (5, 5a).

7. Motor according to any one of the preceding claims, wherein at least a portion of the windings (6, 6a, 6b, 6c) is secured to a carrier structure (8) forming a stator (4).

8. Motor (1) or generator according to the preceding claim, wherein at least two coils (6b, 6c) are carried by a common structure (9).

9. Motor (1) or generator according to the preceding claim, wherein the common structure (9) to said at least two coils (6b, 6c) is connected to the carrier structure (8).

10. Motor (1) or generator according to any one of the preceding claims, wherein said at least two magnets (5, 5a) are carried towards the periphery of the body (2a) of the rotor (2) forming a first assembly. revolution of magnets (5, 5a) and windings (6, 6a, 6b, 6c).

11. Motor (1) or generator according to the preceding claim, which has at least a second set of magnets and coils, the second set of magnets and winding being closer to the drive shaft (3, 3a) than the first set.