A ROTOR AND PRODUCTION OF A ROTOR OF A ROTATING ELECTRICAL MACHINE

Abstract

The invention relates to a method for producing a rotor (14) for a rotating electrical machine (10) in which at least one rotor winding (20) is introduced into a rotor laminated core (16) of the rotor (14) in an electrically insulated manner, wherein the rotor winding (20) is designed as an electrically insulated cage and/or as a damper loop at least partially by means of an additive production method in the rotor laminated core (16), wherein an electrical insulation layer (46) is formed at the same time as the rotor winding (20) is formed between an electrical conductor (22) of the rotor winding (20) and the rotor laminated core (16) and/or between adjacent conductors (22) of the rotor winding (20).

Claims

1.-18. (canceled)

19. A method for producing a rotor for a rotating electrical machine, said method comprising; forming a rotor winding embodied as an electrically insulated cage and/or as a damper loop in a rotor laminated core through an additive production process; and forming a layer of electrical insulation between an electrical conductor of the rotor winding and the rotor laminated core and/or between adjacent conductors of the rotor winding, while the rotor winding is formed.

20. The method of claim 19, wherein the rotor winding is embodied as at least two cages electrically insulated from one another.

21. The method of claim 19, wherein the layer of electrical insulation is formed by deposition of an electrically insulating ceramic material.

22. The method of claim 19, wherein the layer of electrical insulation is formed at least in part by a chemical reaction of a surface of the electrical conductor of the rotor winding with a further substance.

23. The method of claim 19, wherein the rotor laminated core is formed together with the rotor winding.

24. The method of claim 19, wherein the layer of electrical insulation is formed at least partly by deposition of a plastic.

25. The method of claim 19, further comprising: forming a short circuit ring at an axial end of the rotor laminated core; and forming the short circuit ring with a cooling unit

26. The method of claim 25, wherein the cooling unit extends from the short circuit ring beyond an axial extent of the rotor laminated core.

27. The method of claim 19, further comprising: forming the electrical conductor of the rotor winding in a radially outwardly open slot of the rotor laminated core and closing off the slot by a slot closure, in particular a magnetic slot closure, preferably through the additive production process.

28. The method of claim 19, further comprising arranging the electrical conductor of the rotor winding in a plane that extends outside an axis of rotation of the rotor.

29. The method of claim 19, further comprising forming at least one of the electrical conductors of the rotor winding in the rotor laminated core such as to establish a predetermined harmonic effect in relation to a magnetic field of a stator of the electrical machine during operation of the electrical machine.

30. The method of claim 19, further comprising forming at least one of the electrical conductors through the additive production process such as to at least partly extend transversely to a direction of current conveyance determined by the at least one of the electrical conductors.

31. The method of claim 30, further comprising changing a dimension of the at least one of the electrical conductors, in particular transverse to the direction of current conveyance determined by the at least one of the electrical conductors.

32. The method of claim 19, further comprising changing a cross-sectional surface of at least one of the electrical conductors in a longitudinal extent direction of the at least one of the electrical conductors during production by the additive production process.

33. A rotor for a rotating electrical machine, comprising: a rotor laminated core; a rotor winding inserted into the rotor laminated core electrically insulated and formed as an electrically insulated cage and/or as a damper loop; and a layer of electrical insulation formed between an electrical conductor of the rotor winding and the rotor laminated core and/or between adjacent electrical conductors of the rotor winding, with a material of at least one of the electrical conductors being changed, in particular transverse to a direction of current conveyance determined by the at least one of the electrical conductors and/or a cross-sectional surface in a longitudinal extent of the at least one of the electrical conductors.

34. The rotor of claim 33, wherein the at least one of the electrical conductors, at least transverse to direction of current conveyance determined by the at least one of the electrical conductors, has a layer structure with at least two layers made of materials that differ from one another.

35. The rotor of claim 33, wherein the at least one of the electrical conductors, in a longitudinal extent direction of the least one of the electrical conductors, has two cross-sectional surfaces that differ from one another.

36. A rotor for a rotating electrical machine, comprising: a rotor laminated core; a rotor winding inserted into the rotor laminated core electrically insulated in the form of at least two different cages that are electrically insulated from one another; and a layer of electrical insulation formed between an electrical conductor of the rotor winding and the rotor laminated core and/or between adjacent electrical conductors of the rotor winding, wherein in the rotor laminated core, guided sections of electrical conductors assigned to the cages respectively are arranged such that the guided sections have in a direction of their longitudinal extent at least two different spacings from one another.

37. The rotor of claim 36, wherein the at least one of the electrical conductors, at least transverse to direction of current conveyance determined by the at least one of the electrical conductors, has a layer structure with at least two layers made of materials that differ from one another.

38. The rotor of claim 36, wherein the at least one of the electrical conductors, in a longitudinal extent direction of the least one of the electrical conductors, has two cross-sectional surfaces that differ from one another.

39. A rotating electrical machine, comprising: a stator; and a rotor supported rotatably in an opening of the stator, said rotor being configured in one of two ways, a first way in which the rotor comprises a rotor laminated core, a rotor winding inserted into the rotor laminated core electrically insulated and formed as an electrically insulated cage and/or as a damper loop, and a layer of electrical insulation formed between an electrical conductor of the rotor winding and the rotor laminated core and/or between adjacent electrical conductors of the rotor winding, with a material of at least one of the electrical conductors being changed, hi particular transverse to a direction of current conveyance determined by the at least one of the electrical conductors and/or a cross-sectional surface in a longitudinal extent of the at least one of the electrical conductors, a second way in which the rotor comprises a rotor laminated core, a rotor winding inserted into the rotor laminated core electrically insulated hi the form of at least two different cages that are electrically insulated from one another, and a layer of electrical insulation formed between an electrical conductor of the rotor winding and the rotor laminated core and/or between adjacent electrical conductors of the rotor winding, wherein hi the rotor laminated core, guided sections of electrical conductors assigned to the cages respectively are arranged such that the guided sections have in a direction of their longitudinal extent at least two different spacings from one another.

Description

[0057] In the figures:

[0058] FIG. 1 shows a schematic sectional view of a rotating electrical machine with a cage rotor along an axis of rotation of the rotor;

[0059] FIG. 2 shows a schematic end-face side view of a first cage rotor in accordance with a first exemplary embodiment with two cages embodied electrically insulated from one another, as well as two short circuit rings arranged radially above one another, produced with a production method of the invention;

[0060] FIG. 3 shows a schematic sectional view in the area of an end-face side end of the rotor in accordance with FIG. 2;

[0061] FIG. 4 shows a schematic end-face side view of a second cage rotor with two cages embodied electrically insulated from one another, in accordance with a second exemplary embodiment, wherein the short circuit rings of the cages are arranged in one another, produced with the production method of the invention;

[0062] FIG. 5 shows a schematic sectional view in the area of the end-face side end of the rotor in accordance with FIG. 4;

[0063] FIG. 6 shows a schematic sectional diagram of a stator for the cage rotor in accordance with one of the preceding exemplary embodiments, wherein the stator has tooth-wound coils in accordance with an embodiment as a two-pole rotating electrical machine;

[0064] FIG. 7 shows, in a schematic representation, a diagram by means of which the magnetic field in the air gap distributed over the circumference is represented by bars;

[0065] FIG. 8 shows a schematic cross-sectional diagram of a section of the cage rotor in accordance with one of the preceding figures transverse to the axis of rotation of the rotor in the area of an air gap;

[0066] FIG. 9 shows a schematic perspective view of an electrical conductor of the rotor winding of a cage rotor, wherein the electrical conductor is produced in layers radially from the inside outwards by means of the additive production method;

[0067] FIG. 10 shows a section of a schematic sectional view in a radially outer area of a slot of a cage rotor, wherein an electrical conductor produced in layers by means of the additive production method is arranged in the slot;

[0068] FIG. 11 shows a section of a schematic sectional view in a radially outer area of a slot of a cage rotor, wherein two electrical conductors insulated electrically from one another of different cages of a cage rotor insulated electrically from one another are arranged in the slot.

[0069] FIG. 1 shows, in a schematic sectional view, a rotating electrical machine 10, which, in this figure, is embodied as an asynchronous machine for a connection to a three-phase ac voltage network, and which has a stator 12 that is arranged in a rotationally fixed manner. The stator 12 has a stator laminated core 34, in which a stator winding 36 is arranged. In FIG. 1 the winding heads 18 of the stator winding 36 projecting beyond the stator laminated core 34 on the long side are visible. The section in FIG. 1 here is a longitudinal section along an axis of rotation 30 of a rotor 14, which is embodied as a cage rotor.

[0070] The rotor 14 is arranged rotatably hi the asynchronous machine 10 and is held rotatably in its position relative to the stator 12 via bearings not shown in any greater detail. The rotor 14 has a rotor laminated core 16, which comprises a rotor winding 20. The rotor winding 20 comprises electrical conductors 22, which are embodied as bars. Short circuit ring units 28 are provided in each case on end-face side ends 38 of the rotor laminated core 16, by means of which the electrical conductors 22 (FIG. 3, 5, 8) are coupled to each other on the end-face side in each case in order to form cages.

[0071] The rotor 14 further has a rotor shaft 40, which serves for connection to a rotatable mechanical device. The rotatable mechanical device can have any given function, for example a drive function for an industrial machine, an electrically driven vehicle and/or the like. Moreover the mechanical device can naturally also be an internal combustion engine, a wind turbine and/or the like. Depending on its operating mode, the cage rotor 14 can be supplied with mechanical energy in the form of the rotational movement, so that the asynchronous machine 10 can be operated in a generator mode, or the asynchronous machine 10 can obtain electrical energy via the electrical energy supply network connected to it and can provide a torque in motor mode via the rotor 14 and the rotor shaft 40.

[0072] FIG. 2 shows, in a schematic end-face side view, a first embodiment for the asynchronous machine 10 in accordance with FIG. 1, wherein the rotor 14 has two short circuit rings 24, 26 on the end face side in each case, which form the short circuit ring unit 28. The embodiment of the short circuit rings 24, 26 is provided in the same way on both end-face skies of the rotor 14 here. The short circuit rings 24, 26 are arranged radially above one another here, so that the short circuit ring 26 is radially enclosed by the short circuit ring 24. FIG. 3 illustrates this embodiment. It can further be seen that the short circuit ring 24 has axially projecting air scoops 32. An air guidance can be generated with these air scoops 32, which serves to cool the rotor 14 on the end-face side.

[0073] It can further be seen from FIG. 3 that the short circuit rings 24, 26 are each connected to the electrical conductor 22. The electrical conductors 22 in this figure are embodied as bar conductors and project axially beyond the end-face side end 38 of the rotor laminated core 16 by a distance a. The short circuit rings 24, 26 are therefore not in direct contact with the rotor laminated core 16. The electrical conductors 22 are each linked electrically-conductively alternately in the circumferential direction to one of the short circuit rings 24, 26. This enables cages electrically insulated from one another to be provided, which, as will be explained below, results in an improved function of the asynchronous machine 10.

[0074] FIG. 8 shows schematically, in a sectional cross-sectional diagram, section in the area of the air gap between the stator 12 and the rotor 14. It can be seen from FIG. 8 that the electrical conductors 22 are embodied as bar conductors, The electrical conductors 22 are each connected electrically-conductively alternately to the short circuit ring 24 or to the short circuit ring 26. The electrical conductors 22 are formed in slots 44 of the rotor laminated core 16 that are open radially outwards and essentially extend in the axial direction in parallel to the axis of rotation 30 of the rotor 14. Although there is provision in this figure for the slots to be formed parallel to the axis of rotation 30, there can also be provision however for the slots to be embodied beveled in relation to the axis of rotation 30 of the rotor. The bevel can vary depending on the application for the asynchronous machine.

[0075] FIG. 4 now shows, in a view like that shown in FIG. 2, an alternate second embodiment for the short circuit ring unit 28 in accordance with FIG. 1. In the embodiment depicted in FIG. 4 there is provision for a first short circuit ring 24 to accommodate a second short circuit ring 26, so that the second short circuit ring 26 is arranged within the short circuit ring 24. The short circuit rings 24, 26 are electrically insulated from one another by means of a layer of electrical insulation 46. The layer of electrical insulation 46 is formed in this example by an electrically insulating oxide layer. The layer of electrical insulation 46 is produced using an additive production method for producing the rotor 14.

[0076] In this way the electrical conductors 22 that are connected to the different short circuit rings 24, 26 will also be electrically insulated from said rings as well and also from one another in relation to the rotor laminated core 16. FIG. 5, in a comparable diagram to FIG. 3, shows a longitudinal section along the axis of rotation 30 of the rotor 14 in the area of the end-face side end 38 of the rotor laminated core 16. In this figure the short circuit ring 26 is radially accessible on the end-face side. In an alternate embodiment the short circuit ring 26 can naturally also be enclosed completely by the material of the short circuit ring 24. A wide range of construction options is opened up here by the additive production method, so that the short circuit ring unit 28 can be adapted to different requirements as required with great precision.

[0077] FIG. 6 now shows, in a schematic diagram, an embodiment for the stator 12 of the asynchronous machine 10 in accordance with FIG. 1. It can be seen from FIG. 6 that the stator 12 features the stator laminated core 34, which is equipped with tooth-wound coils 18, which form the stator winding 36. In this figure there is provision that, for embodiment of a two-pole asynchronous machine 10, tooth-wound coils are provided in the circumferential direction, which are connected accordingly to the three-phase electrical energy supply network for forming a rotary field. For this reason the three-phase electrical energy supply network can also be provided by a suitably embodied converter, which is connected for its part to an electrical supply network, an electrical energy store, for example a high-voltage battery, and/or the like.

[0078] Each of the tooth-wound coils 18 has a yoke 50, which extends axially in the direction of the axis of rotation 30. A respective tooth is formed by this. The yoke 50 is bordered by electrical conductors 52, through which the same electrical current flows in the opposite direction and, in operation according to specification and a respective coil 18, form the stator winding 36. Through this a magnetic field is generated in a predetermined way along the extent of the yoke 50, which is introduced into an air gap 48 (FIG. 8). The field runs via the air gap 48 into the rotor 14 and here in particular into the rotor laminated core 16, so that the desired electromagnetic interlinkage can be brought about.

[0079] It is to be noted that naturally the magnetic field and also the current flowing through the electrical conductors 52 involves variables that change over time.

[0080] FIG. 7 shows, in a schematic graphical diagram, a bar diagram, which schematically represents the magnetic field in the area of the air gap 48 created in the circumferential direction by the stator 12 in accordance with FIG. 6. .sub.p designates a half rotation phase in relation to the pole division. The individual bars are able to be assigned individual tooth-wound cons 18 in each case. The bars 1 to 12, which are shown in FIG. 7, are naturally likewise variable in accordance with the timing variability. On application of a three-phase alternating line voltage of 50 Hz the bars 1 to 12 vary accordingly over time. Consequently the stator depicted in FIG. 6 provides a corresponding rotating field. The bar diagram thus shows the magnetic field at a fixed point in time.

[0081] FIG. 8 now shows a section in the area of the air gap 48 in a cross-sectional diagram transverse to the axis of rotation 30. It can be seen that, on the rotor side, opposite to twelve tooth-wound coils 18 of the stator 12 thirteen trapezoidal bars are provided as electrical conductors 22. The electrical conductors 22as already explained aboveare alternately connected electrically-conductively to one of the short circuit rings 24, 26. Each of the electrical conductors 22 is embodied in a radial longitudinal slot 44 of the rotor laminated core 16 open to the outside. Moreover each of the electrical conductors 22 is arranged electrically insulated from the rotor laminated core 16 by a layer of electrical insulation 46.

[0082] In the present invention there is provision for the electrical conductors 22 as well as the layer of electrical insulation 46 to be produced by an additive production method. Initially, in the familiar way, the rotor laminated core 16 is prepared, by individual laminations of the rotor laminated core 16 being produced. This can be done by punching or the like. Then the individual laminations of the rotor laminated core 16 are provided with a layer of electrical insulation not shown in any further detail.

[0083] In a next step, by means of selective laser melting (SLS) as an additive production method, a first of the two short circuit ring units 28 is initially produced, by copper being deposited in a predeterminable way, in order to produce the short circuit rings 24, 26. As the method progresses, directly thereafter the electrical conductors 22, here the trapezoidal conductor bars, are embodied step-by-step. As the embodying of the electrical conductors 22 progresses, the individual laminations of the rotor laminated core 16 are inserted and in this way the entire rotor 14 is produced in a continuous working method.

[0084] To provide the reliable function, during the embodiment of the electrical conductor 22, its surface is provided with a layer of electrical insulation 46. For this purpose an appropriate electrically insulating ceramic layer is deposited, which in the completed rotor 14 formed is arranged between the electrical conductors 22 and the rotor laminated core 16. The additive production method is continued until such time as the axially opposite short circuit ring unit 28 is completely formed.

[0085] Moreover there can be provision for the short circuit rings 24, 26 to be able to be provided on their end-face side with air guidance scoops, like the air scoop 32. This enables a cooling function to be provided for the rotor 14 and also for the entire electrical machine 10 at the same time.

[0086] A stray flux is further indicated schematically in FIG. 8 with the reference number 42. This stray flux 42 can be reduced by the second cage winding, which is embodied electrically insulated from the first cage winding, so that overall an improvement in the function of the electrical machine 10 can be achieved.

[0087] FIG. 9 shows a schematic perspective view of an electrical conductor 54 of a rotor winding of a cage rotor not shown in any greater detail. In this embodiment the electrical conductor 54 is produced in layers radially from the inside outwards by means of the additive production method. The electrical conductor 54 has a longitudinal axis 56, in which an electrical current is conveyed during operation according to specification. The electrical conductor 54 can be produced at the desired position by individual layers being deposited along the longitudinal axis 56 by means of the additive production method. Such an electrical conductor 54 is shown in FIG. 10. For this reason a blank with a diameter smaller than that required can be provided, which is then built up by means of the additive production method to the desired geometry and size.

[0088] FIG. 10 shows a section of a schematic sectional view in a radially outer area of a rotor laminated core 16 of a cage rotor. The area shown comprises a slot 44, in which an electrical conductor 54 produced layer-by-layer by means of the additive production method is arranged. The electrical conductor 54, because of the additive production method, has a layer structure comprising layers 60, which are arranged in above one another in the slot 44 in the radial direction of the cage rotor. The layers 60 in this example directly adjoin one another and in this embodiment are not electrically insulated from one another. Not shown in FIG. 10 however is the fact that the electrical conductor 54 is arranged electrically insulated from the rotor laminated core 16.

[0089] The individual layers 60 can for this reason be made of toe same material, in this embodiment however there is provision for the individual layers to have different materials from one another. Thus there is provision for the lowest or radially innermost layer 60 to be formed essentially from copper. The uppermost or radially outermost layer 60 on the other hand is essentially formed from aluminum. Layers 60 lying radially outwards between these two layers have a decreasing copper content and an increasing aluminum content. The materials selected naturally can be varied in almost any given way as required. An inverted layer arrangement is also possible.

[0090] The slot 44, after the electrical conductor 54 has been arranged in the slot 44 by means of the additive production method, is closed off radially outwards by means of a slot closure 58. The slot closure 58 in this example is likewise produced by the additive production method. A magnetizable material is provided as the material in this example. As an alternative or in addition however a non-magnetizable material can also be provided, for example a plastic, in particular a composite material, but also combinations hereof and the like.

[0091] FIG. 11 shows a section of a schematic sectional view in a radially outer area of a cage rotor. Arranged in a slot 44 of a rotor laminated core 16 are two electrical conductors 62, 64 insulated from one another of different cages of a cage rotor electrically insulated from one another. For this purpose the electrical conductor 64 is first inserted into the slot 44 by means of the additive production method. A layer of electrical insulation 66 is then attached to the electrical conductor 64 by means of the additive production method. Then the electrical conductor 62 is likewise attached to the layer of electrical insulation 66 by means of the additive production method. Finally the slot 44as already explained for the embodiment depicted in FIG. 10is closed off by means of a slot closure 58. Here too the electrical insulation of the electrical conductors 62, 64 to the rotor laminated core is not shown in any further detail. For this reason however, it can likewise be produced by means of the additive production method, either before the electrical conductors 62, 64 are inserted into the slot 44, or also during this process. Naturally the individual electrical conductors 62, 64 can also have a layer structureas already explained with reference to FIG. 10.

[0092] In the embodiments depicted in FIGS. 10 and 11, the rotor laminated core 16, and thus also the slot 44, are already present before the insertion of the electrical conductors 54, 62, 64. There can however also be provision for the rotor laminated core 16 and any electrical insulations to be produced by means of the additive production method at the same time as the electrical conductors 54, 62, 64.

[0093] The exemplary embodiments described above merely serve to explain the invention and are not restrictive for said invention. In particular features of the exemplary embodiments can naturally be combined with one another in any given way, in order to arrive at further embodiments as per requirements, without departing from the ideas of the invention. In particular different additive production methods can naturally also be combined with one another, in order to arrive at new production methods for the rotor of the rotating electrical machine,

[0094] Moreover the invention can naturally also be applied to the stator of the rotating electrical machine.