WO2006045772A1

WO2006045772A1 - Electrical machine

Info

Publication number: WO2006045772A1
Application number: PCT/EP2005/055493
Authority: WO
Inventors: Gerhard Dorr
Original assignee: Siemens Aktiengesellschaft
Priority date: 2004-10-26
Filing date: 2005-10-24
Publication date: 2006-05-04
Also published as: DE102004052070A1; EP1805872A1

Abstract

The invention relates to an electrical machine comprising a rotor (3) and a stator (2). The rotor (3) can rotate about a rotation axis (4). The stator (2) is mounted so that it encircles the rotation axis (4), and the stator is cooled by a liquid cooling medium. The lines (5) for the cooling medium are rigid and are attached to the stator (2) itself.

Description

description

Electric machine

The present invention relates to an electric machine with a rotor rotatable about a rotation axis and a rotation axis surrounding the arranged, cooled by means of a liq ^¬ sigen cooling medium stand.

Such electrical machines are well known.

Electric machines are available as liquid-cooled (usually water-cooled) machine therefore particularly advantageous because a very efficient cooling can be achieved with this type of electrical machines and more complete insbeson ^¬ a compact machine design is possible. A compact machine design is particularly advantageous for various applications, for example in vehicle drives. In addition, liquid-cooled electric machines are also particularly quiet because no fan is required.

Liquid cooled electric machines are made in the prior art with housings enclosing a water jacket. Through the water jacket cooling water is pumped, thereby resulting in the electrical machine loss ^¬ heat is dissipated.

The housing of such electrical machines is usually constructed of several parts, wherein at least one part is provided with spi ^¬ ralförmigen grooves, which form in cooperation with another housing part closed guide channels for the cooling water.

The type of construction of the liquid-cooled electrical machines of the prior art has several disadvantages. For example, the heat is dissipated indirectly. So it must first be discharged through the contact of the stator core into the housing, the resulting heat loss, only then the heat can be absorbed by the flowing in the cooling channels cooling water.

Furthermore, the design of the prior art ferti¬ supply technology is very cumbersome, since both the individual parts of the housing and the composite housing would have to be machined several times consuming. As a result, since ^¬ of the cost of the electric machine increase.

In other embodiments of water-cooled electrical machines, attempts are made to form the cooling channels as cast-in tubes. However, this procedure has proven to be prone to failure and expensive in the past.

The object of the present invention is to fen a simple construction electric machine to sheep, in a simple, reliable and efficient flues ^¬ sigkeitskühlung is realized.

The object is achieved in that even rigid lines for the cooling medium are applied to the stand itself.

This type of cooling of the electric machine is initially efficient, because the heat loss arising in the stator can di ^¬ rectly dissipated to the lines for the cooling medium. It is also simple and reliable because the lines can be made as such in advance and then only the finished lines on the stand aufge¬ must be introduced.

Preferably, each of the lines per se has a constant distance from the axis of rotation. Because this results in a simpler routing. In general, the stand as an outer stator and the rotor are designed as internal rotor and the lines arranged on the outer circumference of the stator. Because this results in a good accessibility of the pipes, for example, for maintenance and inspection purposes. Also, the application to the stand is easier.

The manufacture of the stator of the electric machine according to the invention is particularly simple if the lines extend in one of the main directions of a cylindrical coordinate system related to the axis of rotation. The main direction, in which the lines run, can be alternately the axial direction or the tangential direction of the cylindrical coordinate system.

If the stand has depressions and the lines are arranged in the depressions, a guide for the lines results, as it were, on its own. In addition, in this case, the lines are protected to a limited extent from accidental mechanical effects.

If the lines seen the wells, gene toward the Leitun¬, in cross-section at least substantially ausfül ^¬ len, results in a particularly good heat dissipation.

To fill the wells through the lines, it is particularly advantageous if the lines are rolled into the Vertie ^¬ tests. But it is also possible that the lines are pressurized in the radial direction or in the tangential direction tensile or pressurized.

The rolling of the lines in the recesses and the pressurization in the radial direction are possible regardless of the specific type of wiring. A tensile action in the tangential direction is only useful if the lines are arranged on the outer circumference of the stator and in the tangential direction or the direction the lines has at least one tangential component. A pressure in the tangential direction is only useful if the lines on the inner circumference of the stator are ordered an¬ and extend in the tangential direction or zumin- least one extending in the tangential component on ^¬ point.

The stator consists, as in the prior art also, of a stack of stator laminations extending in the direction of the axis of rotation. For realizing depressions extending in the tangential direction, it is possible, for example, for the stator plates to have either a larger or a smaller sheet surface and to alternate the stator sheets with a smaller sheet surface and the stator sheets with a larger sheet metal surface in groups. For the realization of depressions extending in the axial direction, it is preferred that the stator laminations all have the same sheet-metal surface and the recesses are introduced into the stator laminations. The introduction of the recesses in the stator plates can be done, for example, by punching, especially in conjunction with the punching of the stator plates as such.

The lines may be formed as substantially circular tubes. But they can also have a substantially D-shaped cross-section. They may also have a Läng¬ union cross-section, which is rounded off at its narrow sides. They are preferably made of a metal, e.g. made of copper or aluminum, or of a plastic.

The lines may have been set up in multiple ways Herge ^¬. Preferably, however, the lines are formed as extruded or extruded profile.

The lines can be individual lines that are also individually connected to a cooling medium circuit. But they can also be grouped into meandering groups. be summarized. This is particularly useful in conjunction with egg ^¬ ner axial alignment of the lines.

A water cooling is particularly useful when the electrical machine is designed as a large electric machine. Such large electric machines are often used in ^¬ particular as vehicle drives.

Further advantages and details emerge from the following description of exemplary embodiments in conjunction with the drawings. Here are a schematic diagram:

1 shows schematically an electrical machine,

2 schematically shows a possible first embodiment of the stator of the electric machine of FIG. 1,

3 shows a detail of the stator of FIG. 2,

4 shows a section through the stand of FIG 2 along a

Line IV-IV in FIG. 2,

5 shows a further detail of the stator of FIG. 2, FIG. 6 shows an alternative embodiment of the lines in which FIG

Stand of FIG 2, 7 shows schematically a possible second embodiment of

Stator of the electric machine of FIG 1, 8 shows a partial section through the stator of FIG 7 along a line VIII-VIII in FIG 7,

9 shows a detail of the stator of FIG. 7 before rolling in lines,

FIG. 10 shows the illustration of FIG. 9 after the rolling of the lines, FIG. 11 shows a side view of the stator of FIG. 7 and FIG

12 shows schematically a vehicle with an electric machine according to the invention.

According to FIG. 1, an electrical machine has a housing 1 in which a stator 2 is arranged fixed to the housing. In the housing 1, a rotor 3 is further mounted such that it is rotatable about a rotation axis 4. The stator 2 is obviously designed as an outer stator 2, the rotor 3 as an inner rotor 3. Accordingly, the stator 2 surrounds the rotor 3. Regardless of the configuration of the stator 2 as an outer stator 2, the stator 2 surrounds at least the axis of rotation 4.

According to FIG 1, the electric machine is exemplified as a large electric machine. Least therefore it meets min ^¬ of the following criteria:

- Your power consumption or output P is at least 1 MW.

- The length 1 of the housing 1 is at least 100 cm.

- The diameter d of the housing 1 is at least 75 cm. The volume V surrounded by the housing 1 is at least 0.5 m ³ .

In most cases, even several of the above criteria are met, often even all of the criteria mentioned above. The electric machine can also be smaller in size.

As is indicated schematically in FIG. 1, rigid lines 5 for a liquid cooling medium are applied to the stator 2 itself. As shown in the upper part of FIG 1 lau ^¬ 5 fen lines tangentially to the axis of rotation 4 around, as shown in the lower part of Figure 1 they extend parallel to the rotational axis 4. The upright 2 by means of the liquid cooling medium (in the Usually water) can be cooled. The stator 2 is thus formed as a liquid-cooled stator 2 ausge¬.

As indicated in FIG 1 and is apparent, moreover, also from the walls ^¬ ren FIG, the lines 5 are applied to the stator on the outer periphery of the stator. 2 In principle could also ^¬ th lines 5 but the inner periphery of the stand 2 or to the faces of the stator 2 may be disposed. FIG 2 shows in more detail a possible first Ausgestal ^¬ processing of the stator 2 of the electric machine of FIG 1. Ge ^¬ Mäss FIG 2, the stator depressions 6 on the stand 2 Außen¬ circumferentially tangentially about the rotational axis 4 to run environmentally. The depressions 6 are produced as follows:

The stator 2 consists of a stack of stator laminations 7 ', 7 ".The stack extends in the direction of the axis of rotation 4. This configuration is common and is also shown in FIG 3. Also the connection of the individual stator ^plates 7', 7 "To each other to the stack, for example by welding, clamps or the like, is carried out as is common practice in the art.

The uprights 7 ', 7 "have all the same internal dimensions r1, r2, as shown in FIG 4. However, the uprights 7', which form the depressions 6, have a smaller outer dimension R1 than the uprights 7", which are located between the pillars Wells 6 are arranged. These have a larger Au ^¬ ßenabmessung R2.

The stator laminations 7 'with the smaller outer dimension Rl (and thus also the smaller sheet metal surface) are each combined into groups with 50 to 500 stator laminations 7'. Likewise, the stator plates 7 "with the larger outer dimension R2 (and thus the larger sheet metal surface) are each combined into groups with 50 to 500 stator plates 7". The numbers of these two types of groups do not necessarily have to be the same. But it is possible that they are the same. The depressions 6 are then formed by alternately alternating the stator plates 7 'with a smaller sheet surface and the stator plates 7 "with a larger sheet surface.

The lines 5 are then - see the FIG 2, 4 and 5 - arranged in the recesses 6. They are preferably dimensioned such that, as seen in the direction of the lines 5, the recesses 6 in cross-section at least substantially fill, in particular flat on the stator plates 7 'an¬ lie.

Depending on the number of stator laminations 7 'with a small sheet metal area per group, the lines 5 can have different cross sections. In the embodiment of FIGS 2 to 5 spielsweise have the lines 5 is preferably the Darge ^¬ featured on oblong cross-section, of ten at its Schmalsei- is rounded. With correspondingly smaller number of

Stator laminations 7 'having a smaller sheet area, the Lei¬ could obligations 5 but also (completely or at least in the union Wesent ^¬) and circular tubes may be formed. Furthermore, the lines 5 - see FIG 6 - also have a substantially D-shaped cross-section. The "chord", ie the straight portion of the D-shaped cross section, may alternatively abut the stand 2 or be remote from it.

According to FIG. 4, the lines 5 are tensioned in the tangential direction. Alternatively, they could also, as shown in FIG. 4, be pressurized by means of metal bands 8 in the radial direction. In these two cases, after insertion of the lines 5 into the depressions 6, no deformation of the lines 5 takes place. In these two cases, the chord of the cross section should therefore face the stator 2 when such a cross section is used.

However, it is also possible to insert initially round, in particular circular ^¬ shaped, lines 5 in the recesses 6, wherein the lines 5 are dimensioned such that they do not completely fill the Ver ^¬ recesses 6 and 6 slightly above the upper edge of the recesses survive. If the wires are rolled into the recesses 6 then 5 after the insertion of the cables 5 in the recesses 6, thereby the lines einge¬ suppressed in the recesses 6 5 so that they cross section of the recesses 6 fully constantly fill ^¬. At the same time, at the level the 2 side facing away from the lines 5 automatically the tendon of the then D-shaped cross section.

Regardless of the specific nature of the connection of the lines 5 to the stator 2, however, an intimate planar contact of the lines 5 arises, at least to the stator plates 7 'with a small sheet surface, so that the heat removal from the stator 2 can take place via these.

To optimize the heat dissipation, the lines 5 should consist of a good heat-conducting material. The material should preferably be non-magnetic. These two requirements are met by a variety of metals, especially copper and aluminum. These two metals are therefore preferred as a conductor material. Alternatively, could also ^¬ th lines 5 but from a plastic.

The cables 5 can access a variety of ways Herge ^¬ presents his. Preferably, however, they are produced by extruding or extruding a corresponding profile. This is especially true if the lines 5 have an elongated cross-section which is rounded at its narrow sides (see FIG 4). In principle, however, this type of production is also conceivable and possible in the case of the other line cross sections, that is to say the at least substantially circular cross section or the D-shaped cross section.

In the above first in conjunction with FIGS 2 to 6 ^¬ be described embodiment of the stand 2 of the inventive electric machine have the lines 5 - in each case per se - a constant distance from the axis of rotation 4 on. Furthermore, the lines 5 extend in one of the main directions of a cylindrical coordinate system, which is related to the axis of rotation 4, namely in the tangential direction of the cylindrical coordinate system. But there are also other configurations possible. Thus, in particular, the lines 5 could also be helically applied to the outside ^¬ side of the stator 2, so helically around the rotation axis 4 rotate. Even then, the lines would 5 - each seen by itself - have a constant distance from the axis of rotation. Furthermore, it is possible for the lines 5 to extend in the axial direction, that is to say parallel to the rotation axis 4 of the rotor 3. This second embodiment of the stator 2 of the electric machine according to the invention will be described below - initially in conjunction with FIGS

10 - explained in more detail. In advance but that was hingewie ^¬ sen, that even in this case, the lines 5 - each per se - a constant distance from the Rotationsach¬ se 4 have and one of the main directions of the cylindrical coordinate system see run, namely processing of Axialrich¬ ,

Also in the case of the second embodiment of the stator 2 of the electric machine according to the invention, the stator 2 -see FIG. 7-has recesses 6 in which the lines 5 are arranged. However, in this embodiment, the depressions 6 extend, of course, axially, ie, parallel to the axis of rotation 4. They are preferably produced as follows:

As in the case of the first embodiment, the stator 2 also consists of a stack of stator laminations 7 in the second embodiment, the stack extending in the direction of the axis of rotation 4. In contrast to the first embodiment, however, the stator laminations 7 shown in FIG. 8 all have the same sheet-metal surface. The recesses 6 are introduced in this case in the stator laminations 7, and indeed for all stator laminations 7 at the same radial and tangential position. The introduction of the recesses 6 in the stator plates 7 can be done by punching. The punching can again take place as a common punching process together with the actual punching of the stator laminations 7 from a larger sheet metal. The recesses 6 are, as already mentioned, arranged in the second embodiment of the stator 2 at all stator plates 7 at the same positions. Therefore, the mutually angereih¬ th stator plates 7 form - see Figures 9 and 10 - axially continuous recesses 6, in which the leads 5 are ^¬ are introduced.

For introducing the lines 5 into the recesses 6 lines 5 are preferably inserted into the recesses 6, which are initially formed as a circular or at least ^{Wesentli ¬} chen circular tubes. Thereafter, the lines 5 are rolled into the recesses 6. By rolling in, the lines 5 fill the recesses 6 (viewed in the direction of the lines 5) completely in cross-section and terminate flush with the stator plates 7. Furthermore, by rolling in, there is an intimate form-fitting and force-locking contact of the lines 5 with the stator laminations 7. The lines 5 have a substantially D-shaped cross section after rolling in (see FIG. 10), the chord of the D -förmig cross-section of the stator 2 is applied.

In principle, other mounting options for the lines 5 in the recesses 6 are possible. For example, the lines 5, as indicated by dashed lines in Figures 10 and 11 may be surrounded by metal bands 8, by means of which the lines 5 are pressurized in the radial direction. In this case, the leads 5 may also have a cross section other than a substantially D-shaped. Ins¬ particular, they may be formed as substantially or completely circular tubes or an elongated

Have cross-section which is rounded at its narrow sides. You may even, assuming a corresponding cross-section of the recesses 6, continue to have a D-shaped cross-section, in which case, however, the chord of the D-shaped cross section should be facing the stand 2. Preferably, the recesses 6 - see FIG 8 - are formed such that they have a slightly smaller open width w in their radially outer region than in its radially inner region. Because of this, the lines 5 are secured captive in the depressions 6 after rolling into the depressions 6, similar to a Schwalbenschwanzver¬ bond.

With respect to the material and the manufacturing method for the lines 5, the statements made above in connection with the first embodiment also apply to the second embodiment. The lines 5 can thus be designed in particular as an extruded or extruded profile and preferably consist of a good heat-conducting, anti-magnetic material, in particular of copper or aluminum.

As a rule, both in the first embodiment (FIGS. 2 to 6) and in the second embodiment (FIGS. 7 to 10), there is one separate feed connection per line 5 and one separate discharge connection, by means of which the lines 5 are integrated into a coolant circuit are. In particular, in the second embodiment is in the modification shown in FIG 11 but also possible that the Leitun- are summarized gen to 5 groups, each group is formed ma ^¬ other like or coiled. This Ausgestal ^¬ tung provides in particular the advantage that the supply and discharge port for the respective group on the same face of the electrical machine are arranged.

The electric machine according to the invention is, as already mentioned, preferably ^{ausgebil ¬} det as a large electric machine. Such large electrical machines are in principle universally applicable, for example as a generator of a power plant or as a stationary drive eg cable cars, elevators, etc .. Preferably, however, the electric machine according to FIG 12 - there provided with the reference numeral 9 - in one Vehicle 10 is arranged, for example, a locomotive 10. The electric machine 9 is thus used according to FIG 12 as driving ^¬ zeugantrieb. The electric machine 9 is also used in other vehicles, especially in ships and submarines.

The inventive design of the electric machine or its cooling circuit allows in particular a compact, cost-effective machine design with very efficient and reliable heat dissipation. In addition, the embodiment according to the invention - in contrast to the water-cooled electric machines of the prior art - can also be used with caseless machines.

Claims

claims

1. Electrical machine arranged vice bend with a rotatable around a rotation axis (4) rotor (3) and an axis of rotation (4) cooled by a liquid cooling medium ge ^¬ stand (2), dadurchgekennzeich ^¬ net that on the stand ( 2) even rigid lines (5) are applied for the cooling medium.

2. Electrical machine according to claim 1, characterized in that each of the lines (5) seen in itself has a constant distance from the rotation ^¬ axis (4).

3. Electrical machine according to claim 1 or 2, since ^{¬ characterized in} that the stator

(2) as an outer stand (2) and the rotor (3) as an inner rotor

(3) are formed and that the lines (5) are arranged on Außenum ^¬ catch of the stator (2).

4. Electrical machine according to claim 1, 2 or 3, ^{¬ characterized in} that the Leitun ^¬ gene (5) in one of the main directions of the rotation ^¬ axis (4) related cylindrical coordinate system run fen.

5. Electric machine according to claim 4, characterized in that the main direction is the axial direction of the cylindrical coordinate system.

6. Electric machine according to claim 4, characterized in that the main direction is the tangential direction of the cylindrical coordinate system.

7. Electrical machine according to one of the above claims, characterized in that the Stand (2) recesses (6) and that the lines (5) in the recesses (6) are arranged.

8. Electrical machine according to claim 7, characterized in that the lines (5), the recesses (6) seen in the direction of the lines (5), in cross-section at least substantially fill.

9. Electrical machine according to claim 7 or 8, since - by in that the INTR ^¬ are rolled gen (5) in the recesses (6).

10. Electrical machine according to claim 7 or 8, ^{¬ characterized in} that the lines (5) in the radial direction are pressurized.

11. Electrical machine according to claim 7 or 8, ^{¬ characterized in} that the lines ^¬ gene (5) in the tangential direction tensile or pressurized.

12. Electrical machine according to one of claims 7 to 11, characterized in that the stator (2) consists of a in the direction of the axis of rotation (4) extending stack of stator plates (1 ', 7 ") that the stator plates (7', 7 ") each have either a larger or a smaller sheet metal surface and that the Ständerble ^¬ che (7 ') with a smaller sheet surface and the stator ^plates (7") alternate with larger sheet metal area in groups.

13. Electrical machine according to one of claims 7 to 10, characterized in that the stator (2) consists of a in the direction of the axis of rotation (4) extending stack of stator laminations (7), that the stator laminations (7) all have the same sheet surface and that the recesses (6) in the stator plates (7) are introduced ^¬ .

14. Electrical machine according to claim 13, characterized in that the depressions (6) are formed as punched-out portions of the stator laminations (7).

15. Electrical machine according to one of claims 1 to 14, characterized in that the Lei ^¬ lines (5) as substantially circular tubes (5) are out ^¬ forms.

16. Electrical machine according to one of claims 1 to 14, characterized in that the Lei ^¬ lines (5) have a substantially D-shaped cross-section auf¬.

17. Electrical machine according to one of claims 1 to 14, characterized in that the Lei ^¬ lines (5) have an elongated cross-section which is rounded at its narrow sides.

18. Electrical machine according to one of the above claims, characterized in that the Lei ^¬ lines (5) made of a metal, such as copper or aluminum, or consist of a plastic.

19. Electrical machine according to one of the above claims, characterized in that the Lei ^¬ lines (5) are formed as extruded or extruded profile from ^¬ .

20. Electrical machine according to one of the above claims, characterized in that the Lei ^¬ obligations (5) to meander-formed groups are summarized.

21. Electrical machine according to one of the above claims, characterized in that it is designed as a large electric machine.

22. An electric machine according to one of the above claims, wherein a vehicle is used as a vehicle drive.