EP2122809A2

EP2122809A2 - Electric machine

Info

Publication number: EP2122809A2
Application number: EP08706364A
Authority: EP
Inventors: Rolf Gloor
Original assignee: Gloor Engineering
Current assignee: Gloor Engineering
Priority date: 2007-02-15
Filing date: 2008-02-15
Publication date: 2009-11-25
Also published as: US20090295237A1; WO2008098403A2; WO2008098403A3; US7990009B2; CN101657955B; CN101657955A

Abstract

In an electric machine for converting electrical energy into mechanical energy and vice-versa, comprising a movable part (k, k', f, fr, fr') and a stationary part (S, M, L, W), the movable part (k, k', f, fr, fr') is designed as an inner rotor (k, k', f, fr, fr') without a winding for transverse magnetic flux. For the purposes of magnetic flux guidance, the rotor (k, k', f, fr, fr') has at least two axially spaced apart magnetic conductors (f), and the stationary part (S, M, L, W) has in the circumferential direction of the electric machine a number of magnetic webs (S, M) which operationally interact with the magnetic conductors (f) of the rotor (k, k', f, fr, fr'). The stationary part (S, M, L, W) has at least one first winding structure (W) and a second winding structure (L) arranged between the axially spaced apart magnetic conductors (f) of the rotor.

Description

Electrical machine Technical field

The present invention relates to the field of electric machines. It relates to such an electrical machine for converting electrical energy into mechanical energy and vice versa, comprising a movable part and a fixed part, wherein in transverse magnetic flux guide, the movable part is designed as an in-line, winding-free rotor, wherein the rotor for the purpose of magnetic flux guide at least two axially spaced from each other magnetic conductor, so that form a first and a second impeller, and the fixed part in the circumferential direction of the machine comprises a number of magnetically effective webs, which are in operative connection with the magnetic conductors of the rotor, said fixed part having at least one first winding structure which is also operatively connected to the axially spaced magnetic conductors of the rotor.

Machine for conversion of electrical to mechanical energy and vice versa, comprising a movable part and a fixed part, wherein in transverse magnetic flux guide, the movable part is designed as an internal, winding-free rotor.

Although such so-called transversal flux machines measured an increased interest because of their very good torque-to-mass ratio, they are called complicated and therefore pose a challenge for the production.

Technological background

The technology of transversal flux guidance has been known for electrical machines for decades. However, transversal flux machines are considered to be complicated to produce, and indeed, known transversal flux machines today have a Onellen electrical rotary machines large number of different components whose assembly is time-consuming and therefore costly.

On the other hand, conventional electrical machines of the drive technology require, for example, on the mechanical side special adjustments for the power transmission, such as a reduction gear, to be able to lead a correspondingly large torque, for example, on the wing hub of a wind power plant. These transmissions are not only associated with additional costs, they also require space, maintenance and friction losses. These shortcomings can only be prevented if drives can be executed without transmission. For this purpose, a large torque is required, which can be met by a transverse flux machine with the outstanding properties in terms of specific torque and efficiency. For this reason, a transverse flux machine appears particularly suitable as a direct drive machine.

Regardless of their good properties, the transversal flux machine has not been supplied with great interest in mass production because of the complicated production.

From DE 35 36 538 Al it is known that in a transverse flux machine according to the number of pole pairs U-profile soft iron elements are installed in a stationary machine part, which close the magnetic circuit. The movable machine part is designed here as an internal, disk-shaped rotor; On its disk surfaces arranged perpendicular to a rotor axis, it has permanent magnets in an alternating sequence for the purpose of excitation. These permanent magnets are subjected to centrifugal forces in accordance with the rotational speed of the machine, which can be a great burden for an adhesive bond between such permanent magnets and the rotors.

DE 195 47 159 AI discloses a transverse flux machine, which works as Außenläuferma- machine with rotating soft iron elements. Their structure does show respect the resulting centrifugal forces a more favorable design variant with respect to the DE 35 36 538 Al _1, however, their structure is relatively complicated, since the outer rotating rotor elements are held by means of an annular structure for each phase,

WO2006126552 discloses an electric machine for converting electrical to mechanical energy and vice versa, comprising a movable part and a fixed part, wherein in transverse magnetic flux guide, the movable part is designed as an internal, winding-free rotor, wherein the rotor for the purpose of magnetic flux guide at least two axially spaced from each other magnetic conductor, so that form a first and a second impeller, and the fixed part in the circumferential direction of the machine comprises a number of magnetically effective webs, which are in operative connection with the magnetic conductors of the rotor, said fixed part having at least one first winding structure which is also operatively connected to the axially spaced magnetic conductors of the rotor.

Presentation of the invention

Based on this prior art, the object of the present invention is to provide an electrical machine which shows an improved torque - machine volume ratio with good centrifugal force resistance.

The object underlying this invention is achieved by an electrical machine according to claim 1. Advantageous embodiments of this machine are the subject of the dependent claims or can be found in the following description and the exemplary embodiments. The present electric-to-mechanical electrical machine and vice versa comprises a movable part and a stationary part, wherein in transverse magnetic flux guide, the movable part is formed as an in-line, winding-free rotor and the rotor is at least two axially spaced from each other for magnetic flux guidance comprises magnetic conductors on so-called impellers, between which the fixed part in the circumferential direction of the machine has a number of magnetically effective webs, which are in operative connection with the magnetic conductors of the rotor and wherein said fixed part has at least one first winding structure with the axial spaced magnetic conductors of the rotor is also in operative connection. In addition, the inventive machine has a second winding structure on the webs, wherein either the first winding structure acts as an armature winding and the second winding structure as a field winding or vice versa and wherein the at least one first and a second impeller radially inward magnetically effective by means of another magnetic Ladder are connected.

The magnetic flux thus proceeds from the magnetically active web of the stationary part via a first magnetic conductor of the rotor to an axially adjacent second magnetic conductor of the rotor and back to the magnetically active web. This magnetic circuit encloses the first winding structure of the stationary part of the electric machine according to the invention.

It goes without saying that these magnetic circuit determining machine parts suffice for a single-phase machine; Of course, several units are to be arranged axially next to each other according to the desired number of phases.

The design of the machine essential to the invention essentially shows rotor elements which are equipped as impellers with individual magnetic conductors and have annular structures of the stationary part of the machine, hereinafter also referred to as stator. called, such as the first winding structure. Thus, it is possible the entire machine disc-shaped (rotor), or annular (stator) to build up axially. In addition, in the machine according to the invention, essentially the impellers and the near-axis, magnetically active connection of adjacent impellers belonging to a phase rotate. A significant advantage of the new electric machine is that a significantly higher torque can be provided with the best possible centrifugal force resistance and thus robustness of the machine, as in state-of-the-art machines, that is, the same size as a known machine provides the new Machine, the larger torque, or if the machine is designed for torque, shows the new electric machine with significantly smaller volume.

In addition, the magnetic circuit structure shows a particularly effective frictional connection, since the first winding structure can be arranged particularly close to the axis in the stator and the magnetic flux is radially closed achsfem on the vanes and the webs in the stator. Because of the winding arrangement close to the axis of the first winding structure comparatively little line copper is used on the one hand, this first winding arrangement is very robust to produce, and on the other hand arises due to the low copper consumption compared to the prior art comparatively high efficiency of the machine with the already mentioned, improved specific torque.

An advantageous embodiment of the electric machine provides that axially adjacent impellers are connected by means of a magnetic conductor; For this purpose, the impellers may have an L-shaped or a T-shaped structure, viewed in a radial section, or may alternatively be spaced apart by a magnetically conductive ring. A further embodiment provides that adjacently arranged impellers may be spaced by a permanent magnet ring. It is advantageous if the machine has an additional, second winding structure between the radially inner, first winding structure and the radially outer web ends in the stator. It is provided that either the first or the second winding structure acts as a field winding or as an armature winding.

Furthermore, each of the webs surrounded by a second winding structure can advantageously be designed as permanent magnets.

The second winding structure may be formed as a single, independent coil windings, wherein each individual coil winding is arranged as a short-circuit winding between the radially inner, first winding structure and the radially outer web ends.

Advantageously, the second winding structure in the circumferential direction of the machine can also be arranged wave-like or loop-shaped between the first winding structure and the radially outer web ends. In the case of the wave-shaped, second winding structure, each web of a machine pole on both sides in the circumferential direction radially extending winding parts and adjacent webs alternately only a tangentially outer or a tangentially inner winding part. In the case of a loop-shaped second winding structure between the first winding structure and the radially outer web ends in the circumferential direction of the machine, each web of a machine pole is surrounded along its radial and tangential web sides by a coil having a number of turns, adjacent coils being respectively the same at the radial web sides Number of turns lie together and at the tangential outer and the tangential inner web pages each only the simple number of turns of a coil occurs; Thus, this loop-shaped, second winding structure allows a more compact design of the machine according to the invention and the compensation of an axial magnetic flux component of this second winding structure. A further advantageous embodiment of the machine provides that the second winding structure is arranged between the first winding structure and a housing bounding the machine, wherein this second winding structure is formed as an embedded winding structure and each part winding of this second winding structure between each two circumferentially adjacent webs is arranged. This second winding structure can be designed as a short-circuit winding, as a wave winding or as a loop winding.

Further advantageous embodiments provide to build the electric machine two and more phases. Optionally, axially adjacent two or more phases may be realized in the fixed part, bounded as a composite of only two impellers of the rotating part of the machine, or each of the two or more phases are each located between directly associated impellers. In the circumferential direction, the two or more phases are installed offset from each other with a desired phase shift.

The new electric machine is further characterized by the fact that it can be implemented as an asynchronous machine or as a synchronous machine. The synchronous machine with asynchronous startup option is also an interesting design,

Their applications range from regenerative to motorized operation. By way of example, wind power plants may be mentioned here or direct drives for vehicles. It is also conceivable that the new electrical machine-because of its above-described, robust construction-is used directly with its impellers as a generator turbine and / or pump, for example in pumped storage power plants, in which case the impellers of the rotor and the webs of the stator correspondingly have adapted, fluidically optimized geometry. Of course, any fluid medium in such a turbomachine is conceivable, such as liquids or gases; it would also be conceivable use as a blower. Short description of the drawing

In the drawing, several embodiments of the invention are shown in simplified form, namely show

1 a, b is a longitudinal sectional view, or a cross-sectional view of the invention according to the electric machine in the embodiment of a three-phase synchronous A with an excitation in the form of short-circuited rings, or a three-phase synchronous machine with an excitation in the form of a loop winding.

2a, b is a longitudinal sectional view, or a cross-sectional view of the inventive electrical machine in the embodiment of the three-phase synchronous machine with an excitation in the form of a wave-shaped winding structure.

3a, b is a longitudinal sectional illustration, or a cross-sectional view of the erfindungsgemäßen electrical machine in the embodiment of a three-phase synchronous A with an excitation in the form of short-circuiting rings, said shorting rings are each formed between embedded in the circumferential direction of the machine webs as embedded shorting rings , or with an excitation in the form of a corresponding loop winding, and the

4a, b, a further embodiment of the machine according to Fig. 3rd Ways to carry out the invention

Fig. I a, b show by way of a three-phase machine, an embodiment of the inventive electric machine in a longitudinal sectional view (Fig. I a) or ₁ in a cross-sectional view (Fig. I b). This is a three-phase asynchronous machine or a synchronous machine with phases Pl, P2 and P3. This machine comprises a rotationally symmetrical housing G, which carries a stationary part S, M ₁ L, W of the machine, wherein on an inner wall of the housing G three axially spaced web rings with a number of webs S, M are arranged. In the circumferential direction, the number of webs S, M in the example of embodiment 32 is what corresponds to the number of poles of the machine.

The webs S, M of the second phase P2 are in the present, three-phase design with respect to the webs S, M of the first phase Pl rotated by one-third of the pole pitch. In the third phase P3 by two-thirds compared to the first phase PI. On the inside of these webs S, M, a concentric winding is attached as a first winding structure W.

A movable part k, k ', f of the machine is arranged on a rotor axis a, on the per phase PI, P2, P3 two impellers fr, fr ¹ are mounted with magnetically conductive vanes f. The wings f are aligned in this embodiment, aligned with each other, said wings f radially and viewed from the rotor axis a from at least in the region of the webs S, M are formed as spaced circumferentially of the machine wings f; below that you can be connected. In the region of the webs S, M are then the number of pole pairs according to a number of wings f, in the present example 16 wings f, distributed over the circumference. Adjacent vanes fr, fr ^{1 of} a respective phase Pl, P2, P3 are connected by means of a magnetically conductive core k, or a permanent magnet k '. Furthermore, the machine has a second winding structure L, Lk, Ls. This second winding structure L, Lk, Ls is formed in the form of individual short-circuit windings Lk or in the form of a loop winding Ls on the webs S ₁ M. In this case, the short-circuit windings Lk or the loop winding Ls with their respective coil axes are arranged parallel to the rotor axis a on the webs S, M. These short-circuit windings Lk, or loop winding Ls extend in the present example between the radially inner web ends Si and the radially outer web ends Sa and thus frame the webs S, M completely. This machine has 32 poles, that is, 16 pairs of poles and 16 wings f on the impellers fr, fr '. The vanes fr, fr 'of all adjacent phases Pl, P2, P3 are in this embodiment aligned with each other, whereas the webs S, M of the phases have a phase shift. This is clear in Fig. I a ₁ in which the corresponding phase-shifted phases PI, P2, P3 appear cut differently. In the phase Pl, the cut passes radially through a short-circuit winding Lk, or a loop winding Ls, the phases P2, P3 have sections through the webs S, M and the short-circuit windings Lk, and the loop winding Ls at the inner web ends Si and the outer bridge ends Sa on. The present machine is used with its short-circuit windings Lk for the excitation and the first winding structure W for the armature winding as an asynchronous machine used; With a loop winding Ls as excitation, this machine according to the invention functions as a synchronous machine or as a non-slip asynchronous machine.

By a current in the first winding structure W creates a flooding, which leaves a magnetic flux Φ arise in the magnetic circuit. The magnetic circuit consists of the core k, k ', two axially adjacent wings f, the two air gaps between wings f and the associated web S, M. Depending on the magnetization of the wings f and their position relative to the webs S, M is formed attractive force (Maxwell force) in the axial and tangential direction between wing f and web S ₁ M. The force in the axial direction causes only a mechanical stress on the components but no remarkable movement, since the wings f and webs S, M can not move in this direction outside their elasticity. The tangential force causes a movement of the wings f, since they can rotate with the rotor axis a. Due to the above-mentioned phase shift of the phases Pl, P2 and P3 results in an approximately constant force in the circumferential direction - depending on the phase sequence in the drive- and thus a torque.

The embodiment of the machine according to the invention shown in FIGS. 2a, b (longitudinal and cross section) has, in addition to the first winding structure W, a second winding structure L, Lw, which is arranged as wave-shaped winding Lw on the webs S, M. This wave-shaped winding Lw is characterized in that all the webs S, M are provided on their radial sides with the wave-shaped winding Lw, whereas in the circumferential direction immediately adjacent webs S, M each alternately only one winding part of the wave-shaped winding Lw at the radially inner web end Si or at the radially outer web end Sa have. If the wave-shaped winding Lw serves as a field winding, then adjacent webs S, M an opposite, magnetic polarity on and there are for example again 16 pole pairs of webs S, M before and 16 wings on the impellers fr, fr '. With the first winding structure W as armature winding, this machine functions as a synchronous machine. Again, the webs S, M of the individual phases Pl, P2, P3 are arranged with a phase shift to each other; Fig. 2a illustrates this at the different sections of the wave-shaped winding Lw, namely with a radial section through this wave-shaped winding Lw in phase Pl and with cuts through the webs S, M of the phases P2 and P3 and through the wave-shaped winding Lw at the outer web end Sa , or at the inner web end Si.

In FIGS. 3a, b, in turn, an asynchronous machine according to the invention is shown in a longitudinal section (FIG. 3a) or in a cross-sectional view (FIG. 3b), similar to that shown in FIGS. 1a, b. The difference lies in the arrangement of the second winding structure L, Lk, which is embodied here as an embedded winding structure, wherein each individual short-circuit winding Lk is respectively arranged between two circumferentially adjacent webs. Compared to the illustration in Fig. I a ₁ b b the short-circuit windings are Lk in Fig. 3a, rotated 90 °, and thus have a tangential magnetic flux direction through. In order to close the magnetic flux Φ, which in the present case is guided via axial air gaps, in this embodiment of the machine according to the invention, the vanes fr, fr 'of each phase are rotated by one pole pitch, because of the tangential flow through the short-circuit windings Lk.

The machine shown in FIGS. 3a, b can also be equipped with a loop winding Ls instead of the short-circuit windings Lk described above; Thus, this machine can also be used as a synchronous machine or as a slip ringless Schleifringasynchronmaschine.

FIGS. 4a, b show a further embodiment of the asynchronous machine, as shown in FIGS. 3a, b. The essential difference here is that the air gap is not axially, but radially directed, wherein the webs S, M and embedded between two webs S short-circuit windings Lk extend radially outward of the machine over the entire width of two adjacent vanes fr, fr ¹ . Again, of course, instead of the short-circuit windings Lk a loop winding Ls be arranged, as already explained above.

Without departing from the spirit of the invention, it is conceivable that the machines illustrated in FIGS. 3 a, b and 4 a, b are provided with an embedded wave winding Lw as second winding structure instead of short-circuit windings.

Furthermore, within the meaning of the invention, it is conceivable that the impellers fr, fr 'are designed as discs with a flange attachment articulated radially inward; that is, the vanes fr, fr 'would have an L-shaped structure in an axial section. In the case of a formed side flange, an impeller fr, fr 'would be T-shaped in an axial section; these two variants are not the subject of figurative representation in the drawing.

Claims

claims

An electric machine for converting electrical energy into mechanical energy and vice versa, comprising a movable part (k, k ¹ , f, fr, fr ') and a fixed part (S ₁ M, L ₁ W), wherein in transverse magnetic flux guidance of movable part (k, k ', f, fr, fr') is formed as an in-line, winding-free rotor (k, k ", f, fr, fr '), the rotor (k, k', f, fr, fr ') for the purpose of magnetic flux guide at least two axially spaced apart magnetic conductor (f), so that a first and a second impeller (fr, fr') form, and the fixed part (S, M ₁ L, W) in the circumferential direction of the machine a number of magnetically active webs (S, M) which are in operative connection with the magnetic conductors (f) of the rotor (k, k 'f, fr, fr'), said fixed part (S, M, L, W ) has at least one first winding structure (W, L), which with the axially spaced magnetic conductors (f) of the rotor (k, k ', f, fr, fr') e- benfalls in Wirkverb Indung is, characterized in that in addition to the first winding structure (W) a second winding structure (L) on the webs (S, M) is arranged, wherein either the first winding structure (W) acts as an armature winding and the second winding structure (L) as an excitation winding or vice versa, and wherein the at least one first and a second impeller (fr, fr ') radially magnetically inwardly magnetically connected by means of another magnetic conductor (k, k') are connected.

2. Electrical machine according to claim 1, characterized in that the fixed part (S, M, L, W) corresponding to a number of poles of the machine number of webs (S, M), each with a radially inner web end (Si) and with each a radially outer web end (Sa), the first winding structure (W) being designed as a ring winding, and the second winding structure (L) being radially strives between the inside and the outside lying bridge ends (Si, Sa) extends.

3. Electrical machine according to one of claims 1 or 2, characterized in that the first winding structure (W) as a ring winding (W) coaxially to a rotor axis (a) is formed.

4. Electrical machine according to claim 3, characterized in that the second winding structure (L) as one of the number of poles of the machine corresponding number of short-circuit windings (Lk) between the first radially inner winding structure (W) and the radially outer web ends (Sa) is trained.

5. Electrical machine according to claim 3, characterized in that the second winding structure (L) between the first winding structure (W) and the radially outer web ends (Sa) in the circumferential direction is wave-shaped, each web (S ₁ M) of a Maschinenpols of radially extending Windungsteilen is limited and adjacent webs (S, M) alternately only a tangentially outer winding part or a tangentially inner winding part of the second winding structure (Lw) have.

6. Electrical machine according to claim 3, characterized in that the second winding structure (L) between the first winding structure (W) and the radially outer web ends (Sa) is arranged loop-shaped in the circumferential direction of the machine, wherein each web (S ₁ M) of a Machine pole circumferentially and along its radial and tangential web sides of a coil (Ls) is surrounded by a number of turns, wherein at the radial web sides adjacent coils (Ls) each with the same number of turns together and are performed with alternating winding sense.

7. Electrical machine according to claim 3, characterized in that the second winding structure (L) between the first winding structure (W) and a machine-limiting housing (G) is arranged, said second winding structure (L) is formed as an embedded winding structure and each partial winding of this second winding structure (L) is arranged between in each case two circumferentially adjacent webs (S).

8. Electrical machine according to claim 7, characterized in that the second winding structure (L) as a short-circuit winding (Lk), as a wave winding (Lw) or as a loop winding (Ls) is formed.

9. Electrical machine according to one of the preceding claims, characterized in that the machine is configured in two or more phases, wherein in each case a fixed part (S, M, L, W) is present per phase, and these at least two fixed parts (S , M, L, W) are arranged side by side in an axial direction of the machine.

10. Electrical machine according to claim 9, characterized in that the at least two fixed parts (S, M, L, W) are arranged circumferentially against each other with a phase shift twisted.

1 1. Electrical machine according to one of claims 9 or 10, characterized in that the at least two fixed parts (S, M, L, W) are arranged between two axially spaced apart magnetic conductors (f) of the rotor, or that at least two fixed parts (S, M, L, W) are axially spaced from each other and each between two axially spaced apart magnetic conductors (f) of the rotor (k, k ', f, fr, fr') are arranged.

12. Electrical machine according to one of the preceding claims, characterized in that the magnetic conductor (k, k ¹ ) of the winding-free rotor (k, k ', f, fr, fr ¹ ) as a permanent magnet (k ¹ ) are formed.

13. Electrical machine according to one of the preceding claims, characterized marked, that in each case by a second winding structure (L) surrounded webs (S, M) as permanent magnets (M) are formed.