DE102023129917B3 - Rotor arrangement, electric machine and method for manufacturing - Google Patents

Abstract

A rotor assembly has a rotor core (30) with rotor slots (32), a rotor winding assembly (40), a first cap (51), a second cap (52), and tubes (53), wherein the first cap (51) and the second cap (52) are arranged on two mutually opposite axial sides (15, 16) of the rotor core (30), wherein the rotor winding assembly (40) has rotor windings (41) extending through the rotor slots (32), wherein the first cap (51) has a first channel arrangement (61) and the second cap (52) has a second channel arrangement (62), wherein the tubes (53) each extend through an associated rotor slot (32) and are connected to both the first cap (51) and the second cap (52), and wherein the tubes (53) are each in fluid communication with the first channel arrangement (61) and with the second channel arrangement (62) stand

Description

The invention relates to a rotor arrangement, an electric machine and a method for producing the rotor arrangement.

The DE 10 2021 126 074 A1 shows a rotor with several coolant channels extending over the entire length.

The DE 10 2012 021 600 A1 shows a rotor with a laminated core and a winding.

The DE 10 2012 218 696 B4 shows a rotor with a laminated core and cooling channels.

The DE 10 2021 212 152 A1 shows a rotor with a rotor winding and a hollow shaft.

The DE 10 2021 103 441 A1 shows a rotor with a cooled rotor winding.

The DE 10 2018 220 810 A1 shows a fluid-cooled rotor for an electrical machine. The rotor winding is cooled directly or via near-loss cooling. For this purpose, the spaces between the pole pieces are filled with a potting compound containing axial channels through which a cooling fluid can flow axially along the rotor winding.

The DE 10 2021 133 675 A1 shows a rotor for an electrical machine, comprising a rotor shaft, a laminated core arranged on the rotor shaft and formed from stacked electrical sheets with radially outwardly projecting laminated core projections, rotor windings which are each wound around a laminated core projection, and a pole separator with a cooling channel for a coolant running in the pole separator.

The DE 10 2021 213 717 A1 shows a rotor for an electrical machine, which comprises a rotor shaft, a rotor core mounted on the rotor shaft, end plates with radial projections arranged on the axial sides of the rotor core, and a plurality of rotor windings, wherein the rotor windings are wound around the projections.

It is therefore an object of the invention to provide a new method for producing a rotor arrangement, a new rotor arrangement and a new electric machine.

These tasks are solved by the main claim and the subordinate claims.

1. A) Die erste Kappe wird mit den an der ersten Kappe befestigten Rohren derart relativ zum Rotorkern mit der am Rotorkern angeordneten Rotorwicklungsanordnung bewegt, dass sich die Rohre durch eine jeweils zugeordnete Rotornut des Rotorkerns erstrecken und die erste Kappe auf einer ersten axialen Seite des Rotorkerns angeordnet ist, wobei die Rohre mit der ersten Kanalanordnung in Fluidverbindung stehen;
2. B) Die zweite Kappe wird auf der zur ersten axialen Seite entgegengesetzten zweiten axialen Seite des Rotorkerns relativ zum Rotorkern derart bewegt, dass die Rohre in Fluidverbindung mit der zweiten Kanalanordnung stehen, um über die Rohre eine Fluidverbindung zwischen der ersten Kanalanordnung und der zweiten Kanalanordnung zu bewirken.

A method for manufacturing a rotor assembly comprising a rotor core with rotor slots, a rotor winding assembly, a first cap with a first channel arrangement, a second cap with a second channel arrangement and tubes, comprises the following steps:

1. A) The first cap is moved with the tubes attached to the first cap relative to the rotor core with the rotor winding arrangement arranged on the rotor core such that the tubes extend through a respective associated rotor slot of the rotor core and the first cap is arranged on a first axial side of the rotor core, the tubes being in fluid communication with the first channel arrangement;
2. B) The second cap is moved relative to the rotor core on the second axial side of the rotor core opposite the first axial side such that the tubes are in fluid communication with the second channel arrangement to effect fluid communication between the first channel arrangement and the second channel arrangement via the tubes.

Cooling in the grooves, enabled by the tubes, increases the potential power density of the rotor assembly. The tubes enable good coolant flow even at high speeds and prevent leakage. Furthermore, the sequential assembly allows for process reliability in the rotor assembly. The first cap and the tubes can also be formed as a single piece.

According to a preferred embodiment, after step B), a potting resin is introduced into the rotor grooves on the outside of the tubes. This also ensures a high level of process reliability, and unintentional clogging of the channels by the potting resin can be prevented.

According to a preferred embodiment, prior to step A), the tubes are attached to the first cap at first connection points such that a fluid connection exists between the tubes and the first channel arrangement. The first connection points are sealed such that no fluid connection is established between the inside of the respective tube and the outside of the respective tube at the respective first connection point. This prevents, on the one hand, an unwanted escape of a coolant from the tubes and, on the other hand, the ingress of a casting resin during an injection molding process.

According to a preferred embodiment, in step B), the tubes are attached to the second cap at second connection points such that a fluid connection exists between the tubes and the first channel arrangement, wherein the second connection points are sealed such that At the respective second connection point, no fluid connection is provided between the inside of the respective pipe and the outside of the respective pipe. This prevents coolant leakage and, if necessary, resin ingress, as at the first connection points.

According to a preferred embodiment, the rotor winding arrangement comprises rotor windings that extend through the rotor slots, and the tubes each extend through the associated rotor slot in a region between two adjacent rotor windings. This prevents damage to the rotor windings.

According to a preferred embodiment, a rotor shaft is inserted into the rotor core. This enables good support of the rotor assembly.

• - mit der ersten Kanalanordnung,
• - mit der zweiten Kanalanordnung, oder
• - mit der ersten Kanalanordnung und mit der zweiten Kanalanordnung steht.

According to a preferred embodiment, the rotor shaft has a rotor shaft channel arrangement, wherein the rotor shaft channel arrangement is in fluid communication after insertion

• - with the first channel arrangement,
• - with the second channel arrangement, or
• - with the first channel arrangement and with the second channel arrangement.

This allows coolant to be supplied and, if necessary, removed via the rotor shaft.

According to a preferred embodiment, in step A), the first cap with the tubes attached to the first cap is moved relative to the rotor core with the rotor winding arrangement arranged on the rotor core such that free tube ends of the tubes protrude from the rotor core on the second axial side. This facilitates the positioning of the second cap and control of the movement.

A rotor arrangement for an electric machine comprises a rotor core with rotor slots, a rotor winding arrangement, a first cap, a second cap, and tubes, in which the first cap and the second cap are arranged on two mutually opposite axial sides of the rotor core, in which the rotor winding arrangement has rotor windings which extend through the rotor slots, in which the first cap has a first channel arrangement and the second cap has a second channel arrangement, in which the tubes each extend through an associated rotor slot and are connected to both the first cap and the second cap, and in which the tubes are each in fluid communication with the first channel arrangement and with the second channel arrangement. Such a rotor arrangement enables cooling and thus a high power density. In addition, it can be manufactured with process reliability.

According to a preferred embodiment, a potting resin is arranged in the rotor grooves on the outside of the tubes. Such a potting resin enables cavities to be filled and increases the stability and durability of the rotor assembly.

According to a preferred embodiment, the rotor arrangement has a rotor shaft.

• - mit der ersten Kanalanordnung,
• - mit der zweiten Kanalanordnung, oder
• - mit der ersten Kanalanordnung und mit der zweiten Kanalanordnung.

According to a preferred embodiment, the rotor shaft has a rotor shaft channel arrangement, and the rotor shaft channel arrangement is in fluid communication

• - with the first channel arrangement,
• - with the second channel arrangement, or
• - with the first channel arrangement and with the second channel arrangement.

This allows for good distribution of a coolant.

According to a preferred embodiment, the first channel arrangement, the tubes, and the second channel arrangement form a fluid line, which fluid line is closed between the first channel arrangement and the second channel arrangement to prevent a fluid from escaping in the region of the tubes. This can prevent a coolant from escaping into the rotor grooves.

According to a preferred embodiment, a coolant is provided in the tubes or in the fluid line. This improves the cooling performance. The coolant is preferably conveyed in a coolant circuit.

• - mit der ersten Kanalanordnung,
• - mit der zweiten Kanalanordnung, oder
• - mit der ersten Kanalanordnung und mit der zweiten Kanalanordnung über ein Dichtelement verbunden, welches Dichtelement bevorzugt als gummielastisches Dichtelement oder als Klebeverbindung ausgebildet ist. Die Dichtigkeit der Verbindung kann hierdurch erhöht werden.

According to a preferred embodiment, the tubes

• - with the first channel arrangement,
• - with the second channel arrangement, or
• - connected to the first channel arrangement and to the second channel arrangement via a sealing element, which sealing element is preferably designed as a rubber-elastic sealing element or as an adhesive connection. The tightness of the connection can thereby be increased.

According to a preferred embodiment, the rotor assembly is manufactured by such a method.

An electric machine has such a rotor arrangement and a stator arrangement.

• 1 in einem Querschnitt eine Elektromaschine mit einer Rotoranordnung,
• 2 in einem Längsschnitt zwei Kappen für die Rotoranordnung,
• 3 in einem Längsschnitt die Rotoranordnung von 1, und
• 4 in einer Detaildarstellung ein Detail von 3.

Further details and advantageous developments of the invention will become apparent from the exemplary embodiments described below and illustrated in the drawings, which are in no way to be understood as limiting the invention, as well as from the dependent claims. It is understood that the features mentioned above and those to be explained below can be used not only in the respective combinations specified, but also in other combinations or on their own, without departing from the scope of the present invention. It shows:

• 1 in a cross-section an electric machine with a rotor arrangement,
• 2 in a longitudinal section two caps for the rotor assembly,
• 3 in a longitudinal section the rotor arrangement of 1 , and
• 4 in a detailed view a detail of 3 .

In the following, identical or functionally identical parts are provided with the same reference symbols and are usually described only once. The description builds on each figure to avoid unnecessary repetition.

1 shows an electric machine 10 with a rotor arrangement 20 and a schematically illustrated stator arrangement 12.

The rotor assembly has a rotor core 30 with rotor slots 32, a rotor winding assembly 40 and tubes 53 extending through the rotor slots 32.

The rotor core 30 is preferably designed as a laminated core.

The rotor core 30 has a magnetic yoke 304, also called the armature back or yoke, and stator teeth 302.

The stator teeth 302 have tooth tips 303, which are widened in the embodiment.

The rotor winding assembly 40 has rotor windings 41 which are arranged on the stator teeth 302 and extend through the rotor slots 32.

A slot insulation 304 is preferably provided between the stator teeth 302 and the associated rotor windings.

The rotor core 30 has rotor poles 301, each of which has one of the stator teeth 302 and the associated rotor winding 41.

The tubes 53 extend in the axial direction or at least in a direction with an axial portion through the rotor grooves 32 and enable cooling of the rotor arrangement 20 in the region of the rotor grooves 32.

A potting resin 42 is provided in the rotor grooves 32 on the outside of the tubes 53. The potting resin 42 enables the cavities in the rotor assembly to be closed. By designing the coolant channels as tubes 53, the potting resin 42 can prevent the channels from becoming blocked during production.

Several tubes 53 may also be provided in each rotor groove 32.

The tubes 53 are preferably dimensionally stable, but they can be flexible, preferably elastically flexible. The tubes 53 are preferably made of plastic, but they can also be made of a metal such as aluminum.

The tubes 53 preferably have a circular cross-section, but they may also have a different cross-section, for example square, oval or polygonal.

The rotor assembly 20 has a rotor shaft 80 and preferably a rotor shaft channel assembly 82.

The illustrated rotor assembly 20 is a rotor assembly for a separately excited synchronous machine. Such an electric machine 10 does not require permanent magnets on the rotor assembly 20, and the magnetic flux of the rotor assembly 20 is generated by the rotor winding assembly 40 by energizing it. However, during operation, heat is generated in the area of the winding assembly, and this heat must be dissipated to prevent a reduction in performance.

In the exemplary embodiment, the rotor arrangement 20 is designed with six poles, but it can also have a different number of poles.

The stator arrangement 12, which is only arranged schematically, preferably has a stator core (not shown) and a stator winding arrangement.

2 shows in a schematic longitudinal section a first cap 51, two tubes 53 and a second cap 52.

The first cap 51 has a channel arrangement 61, and the second cap 52 has a channel arrangement 62.

The tubes 53 are connected to the cap 51 at a connection point 55 and are in fluid communication with the channel arrangement 61.

The cap 52 has receptacles 522 for receiving the free ends 531 of the tubes 53, and by placing the cap 52 on the tubes 53, connection points 56 and a fluid connection between the channel arrangement 62 and the tubes 53 are created.

This allows a flow of a schematically indicated coolant 99 from the channel arrangement 62 through the tubes 53 to the channel arrangement 61 and thereby a cooling of the rotor slots 32 and in particular of the rotor windings 41.

3 shows the rotor arrangement 20 in a longitudinal section.

The cap 51 is on a first axial side 15 of the rotor core 30, and the cap 52 is on a second axial side 16 of the rotor core 30. The tubes 53 extend through the rotor slots 32 and are connected to the cap 51 and to the cap 52.

The rotor shaft 80 extends through the rotor core 30.

In the exemplary embodiment, the rotor shaft channel arrangement 82 is in fluid communication with the channel arrangement 62, but it can also alternatively or additionally be in fluid communication with the channel arrangement 61.

The channel arrangement 61, the tubes 53 and the channel arrangement 62 form a fluid line 64 which is closed between the first channel arrangement 61 and the second channel arrangement 62 in order to prevent the coolant 99 from escaping in the region of the tubes 53.

4 shows a detail of 3 .

The tube 53 is connected to the cap 51 via a sealing element 91.

The sealing element 91 is preferably designed as a rubber-elastic sealing element or as an adhesive connection. These sealing elements enable a tight connection in which the coolant 99 at the connection point 55 does not pass from the inside of the tube 53 to the outside of the tube 53, but remains in the provided fluid line 64.

Manufacturing process

In the following, a method for manufacturing the rotor assembly is described with reference to the preceding figures.

In a step A), the first cap 51 with the tubes 53 fastened to the first cap 51 is moved relative to the rotor core 30 with the rotor winding arrangement 40 arranged on the rotor core 30 such that the tubes 53 extend through a respective associated rotor slot 32 of the rotor core 30 and the first cap 51 is arranged on the first axial side 15 of the rotor core 30, wherein the tubes 53 are in fluid communication with the first channel arrangement 61.

In a step B), the second cap 52 on the second axial side 16 of the rotor core 30 opposite the first axial side 15 is moved relative to the rotor core 30 such that the tubes 53 are in fluid communication with the second channel arrangement 62 in order to effect a fluid connection between the first channel arrangement 61 and the second channel arrangement 62 via the tubes 53.

These two steps A) and B) enable a process-reliable assembly of the cooling-suitable caps 51, 52 with the tubes 53.

Preferably, after step B), the potting resin 42 is introduced into the rotor grooves 32 on the outside of the tubes 53. By providing the tubes 53, the fluid lines within the rotor grooves 32 are not blocked.

Preferably, before step A), the tubes 53 are fastened to the first cap 51 at the first connection points 55 such that a fluid connection exists between the tubes 53 and the first channel arrangement 61, wherein the first connection points 55 are sealed such that no fluid connection is created between the inside of the respective tube 53 and the outside of the respective tube 53 at the respective first connection point 55.

Preferably, in step B), the tubes 53 are fastened to the second cap 52 at second connection points 56 such that a fluid connection exists between the tubes 53 and the first channel arrangement 61, wherein the second connection points 56 are sealed such that at the respective second connection point 56 there is no fluid connection between the inside of the respective tube 53 and the outside of the respective tube 53.

Preferably, the rotor winding arrangement 40 has rotor windings 41 that extend through the rotor slots 32, and in which the tubes 53 each extend through the associated rotor slot 32 in a region between two adjacent rotor windings 41. There is generally space for the tubes in this region.

• - mit der ersten Kanalanordnung 61,
• - mit der zweiten Kanalanordnung 62, oder
• - mit der ersten Kanalanordnung 61 und mit der zweiten Kanalanordnung 62

steht.Preferably, the rotor shaft 80 with the rotor shaft channel arrangement 82 is inserted into the rotor core 30, wherein the rotor shaft channel arrangement 82 is in fluid communication

• - with the first channel arrangement 61,
• - with the second channel arrangement 62, or
• - with the first channel arrangement 61 and with the second channel arrangement 62

stands.

Preferably, in step A), the first cap 51 with the tubes 53 attached to the first cap 51 are moved relative to the rotor core 30 with the rotor winding arrangement 40 arranged on the rotor core 30 such that the free tube ends 531 of the tubes 53 protrude from the rotor core 30 on the second axial side 16. This facilitates a connection to the cap 52. Alternatively, the cap 52 can have projections extending toward the cap 51 and enabling a connection to shorter tubes 53.

Naturally, various variations and modifications are possible within the scope of the invention.

Claims (13)

A method for manufacturing a rotor assembly (20) comprising a rotor core (30) with rotor slots (32), a rotor winding assembly (40), a first cap (51) with a first channel arrangement (61), a second cap (52) with a second channel arrangement (62), and tubes (53), which method comprises the following steps: A) The first cap (51) is moved with the tubes (53) attached to the first cap (51) relative to the rotor core (30) with the rotor winding assembly (40) arranged on the rotor core (30) in such a way that the tubes (53) extend through a respective associated rotor slot (32) of the rotor core (30), and the first cap (51) is arranged on a first axial side (15) of the rotor core (30), wherein the tubes (53) are in fluid communication with the first channel arrangement (61); B) The second cap (52) is moved relative to the rotor core (30) on the second axial side (16) of the rotor core (30) opposite the first axial side (15) such that the tubes (53) are in fluid communication with the second channel arrangement (62) in order to effect a fluid connection between the first channel arrangement (61) and the second channel arrangement (62) via the tubes (53). Procedure according to Claim 1 , in which after step B) a potting resin (42) is introduced into the rotor grooves (32) on the outside of the tubes (53). Procedure according to Claim 1 or 2 , in which, before step A), the tubes (53) are fastened to the first cap (51) at the first connection point (55) in such a way that a fluid connection exists between the tubes (53) and the first channel arrangement (61), wherein the first connection points (55) are sealed in such a way that no fluid connection is created between the inside of the respective tube (53) and the outside of the respective tube (53) at the respective first connection point (55). Method according to one of the preceding claims, in which in step B) the tubes (53) are fastened to the second cap (52) at second connection points (56) in such a way that a fluid connection exists between the tubes (53) and the first channel arrangement (61), wherein the second connection points (56) are sealed in such a way that at the respective second connection point (56) no fluid connection is provided between the inside of the respective tube (53) and the outside of the respective tube (53). Method according to one of the preceding claims, in which the rotor winding arrangement (40) has rotor windings (41) which extend through the rotor slots (32), and in which the tubes (53) each extend through the associated rotor slot (32) in a region between two adjacent rotor windings (41). Method according to one of the preceding claims, in which a rotor shaft (80) with a rotor shaft channel arrangement (82) is inserted into the rotor core (30), wherein the rotor shaft channel arrangement (82) is in fluid communication - with the first channel arrangement (61), - with the second channel arrangement (62), or - with the first channel arrangement (61) and with the second channel arrangement (62). Method according to one of the preceding claims, wherein in step A) the first cap (51) with the tubes (53) attached to the first cap (51) is arranged relative to the rotor core (30) with the rotor winding arrangement (40) arranged on the rotor core (30) so that free tube ends (531) of the tubes (53) protrude from the rotor core (30) on the second axial side (16). Rotor assembly for an electric machine (10), which comprises a rotor core (30) with rotor slots (32), a rotor winding assembly (40), a first cap (51), a second cap (52), and tubes (53), wherein the first cap (51) and the second cap (52) are arranged on two mutually opposite axial sides (15, 16) of the rotor core (30), wherein the rotor winding assembly (40) comprises rotor windings (41) extending through the rotor slots (32), wherein the first cap (51) comprises a first channel arrangement (61) and the second cap (52) comprises a second channel arrangement (62), wherein the tubes (53) each extend through an associated rotor slot (32) and are connected to both the first cap (51) and the second cap (52), wherein the tubes (53) - to the first channel arrangement (61), - with the second channel arrangement (62), or - are connected to the first channel arrangement (61) and to the second channel arrangement (62) via a sealing element (91), and in which the tubes (53) are each in fluid communication with the first channel arrangement (61) and with the second channel arrangement (62). Rotor arrangement according to Claim 8 in which a casting resin (42) is arranged in the rotor grooves (32) of the rotor core (30) on the outside of the tubes (53). Rotor arrangement according to Claim 8 or 9 which has a rotor shaft (80) with a rotor shaft channel arrangement (82), and in which the rotor shaft channel arrangement (82) is in fluid communication - with the first channel arrangement (61), - with the second channel arrangement (62), or - with the first channel arrangement (61) and with the second channel arrangement (62). Rotor arrangement according to one of the Claims 8 until 10 , in which the first channel arrangement (61), the tubes (53) and the second channel arrangement (62) form a fluid line (64), which fluid line (64) is closed between the first channel arrangement (61) and the second channel arrangement (62) in order to prevent an escape of a fluid in the region of the tubes (53). Rotor arrangement according to one of the Claims 8 until 11 in which the sealing element (91) is designed as a rubber-elastic sealing element or as an adhesive connection. Electric machine (10) comprising a rotor arrangement according to one of the Claims 8 until 12 and a stator arrangement (12).

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