DE102020109209A1 - Power-generating component of a rotary electric machine and a rotary electric machine - Google Patents

Abstract

The invention relates to a power-generating component of an electric rotary machine and an electric rotary machine with the power-generating component. The power-generating component comprises at least one winding (2) of at least one electrical line element (20) guided at least in sections in slots (10) of the power-generating component (1), wherein the line element (20) has at least one first projection (22) which extends radially in relation to the direction of longitudinal extent of the line element (20) and the first projection (22) rests against a groove wall (11) delimiting a groove (10) and consequently the line element (20) is positioned at least on a section on which the first projection (22) is arranged by the first projection (22) at a distance (30) from the groove wall (11). With the power-generating component proposed here and with it equipped rotary electric machine will be set up conditions are made available which, in a cost-effective and space-saving design, allow optimal cooling and / or a long service life or simplified assembly of their electrical lines or windings.

Description

The invention relates to a power-generating component of an electric rotary machine and to an electric rotary machine with the power-generating component according to the invention.

Depending on the power range or application, it is often necessary to dissipate heat generated by various losses in electrical machines by means of effective cooling. The cooling ensures that critical temperatures, which could damage materials and components, are avoided. In addition, the cooling contributes to improving the efficiency of the electrical machine, since in particular the ohmic resistance in electrical conductors is highly temperature-dependent, as a result of which the power losses increase at higher temperatures.
In particular in the case of electrical machines that have a high torque or power density, surface cooling with heat dissipation to the surrounding air is often not sufficient, so that cooling by means of a cooling fluid is necessary. In principle, oils, water or water mixtures such as. B. water-glycol, but also dielectric liquids are used. However, the use of gaseous media, such as air, as a cooling medium is also not excluded.
In this case, there is usually also the requirement that the cooling system has the smallest possible installation space requirement with low financial and technological expenditure and ensures optimal heat transfer.

In the area of the end windings, there are already different approaches to liquid cooling. Direct conductor cooling in the grooves of the electrical machine, however, continues to be a technical challenge.

There are various publications on jacket cooling and on end winding for cooling electrical machines. While the jacket cooling transfers the heat generated on the surface of the laminated stator core into a cooling circuit, with the end winding cooling the heat is transferred directly to the conductors outside the laminated stator core in the area of the winding heads into the fluid.

the DE 11 2011 103 347 T5 discloses an electrical machine module having an electrical machine including a stator assembly, the stator assembly including a plurality of stator laminations connected together and a plurality of conductors positioned through axial slots of the plurality of stator laminations. There is a coolant channel defined at least partially within the axial slots; and a housing at least partially surrounding the electric machine and at least partially defining a machine cavity, the coolant passage in fluid communication with the machine cavity. Slot liners can be positioned along the axial length of the stator assembly through each of the axial slots and multiple conductors can be positioned through the slot liners.

Further improvements are provided by separately designed cooling channels, which are introduced into the laminated core of the stator, as is the case in FIG EP3157138 A1 is revealed. This document discloses a laminated core of a rotor or stator of an electrical machine, with a plurality of laminations, the laminations having recesses for transporting a cooling medium through the laminated core. In this case, inlet channel sections, return channel sections, tooth inlet channel sections, tooth intermediate channel sections and tooth return channel sections are recesses.

The following documents, among others, are known for improved cooling with direct contact between fluid and conductor in the groove.

That's how she teaches DE10 2015 013 018 A1 a stator for an electrical machine, comprising an annular stator body with a plurality of stator teeth protruding radially from an annular basic shape, which form a receptacle for windings in each case of at least one coil in the circumferential direction between two of the stator teeth. Furthermore, the stator comprises a plurality of coils, the windings of which each revolve around at least one of the stator teeth. The stator furthermore has a stator housing which, taken alone or together with the stator body, completely encloses a cooling volume through which coolant can flow - apart from at least one coolant inflow and at least one coolant outflow. The cooling volume includes at least the coils. In a similar embodiment, the JP2016149900 A2 a cooling structure for an electric rotating machine with a stator, a rotor and a housing, wherein a rotor space and a stator space are separated from one another by a partition wall. A cooling circuit is assigned to the stator. The coolant flow through the stator can be controlled as a function of the pressure conditions via a valve device.

the DE 10 2015 220 852 A1 discloses an electrical machine with an oil-based cooling circuit, wherein the coolant is the power electronics, the phase connection lines and flows through the grooves of the electrical machine and cools.

the DE 10 2016 101 705 A1 is directed to an electrical machine having a stator with a coil device and a rotatable rotor. A coolant can flow directly around the coil device for heat dissipation. A wall element is arranged between the stator and the rotor, which wall element seals the part of the coil device around which the coolant flows in a fluid-tight manner from the rotor. In this case, the wall element comprises magnetically conductive wall sections which, compared to other wall sections of the wall element, specifically have an increased magnetic conductivity. From the US 2017 104 380 AA an electrical machine with a stator and a rotor is known, the stator and / or the rotor having slots. A respective slot is sealed in a fluid-tight manner for receiving a cooling fluid. A winding of a conductor is arranged in a respective slot. Spacers can be used to position the conductors in a respective slot.

the US2009078448 AA teaches an electrical winding conductor with a rectangular cross-section for the production of an electrical winding for electrical devices, with elevations consisting of insulating material being attached to one side of the winding conductor over its entire length at a distance from one another.

Furthermore, there is the approach of integrating a spacer in a stator of an electrical rotating machine for electrical conductors guided in slots of the stator, which spacer realizes a defined distance between the electrical conductor and the laminated core. This spacer can be designed as a slot insert which forms a closed surface on one axial side of the stator.

The present invention is based on the object of providing a power-generating component, in particular a stator, of an electric rotary machine which, in a cost-effective and space-saving design, enables optimal cooling and / or a long service life or simplified assembly.
This object is achieved according to the invention by the power-generating component according to claim 1. An electric rotary machine having the power-generating component is defined in claim 11. Advantageous embodiments of the power-generating component are the subject matter of claims 2 to 10.
The features of the claims can be combined in any technically meaningful manner, in which case the explanations from the following description and features from the figures can also be used, which include additional embodiments of the invention.

The invention relates to a power-generating component of an electric rotary machine, comprising at least one winding of at least one electrical line element guided at least in sections in grooves of the power-generating component. According to the invention, it is provided that the line element has at least one first projection extending radially in relation to the direction of longitudinal extent of the line element, the first projection resting on a groove wall delimiting a groove and consequently the line element at least on a section on which the first projection is arranged, is positioned by the first projection at a distance from the groove wall.

The terms “axial” and “radial” relate in the context of the present invention to the longitudinal axis of the relevant line element.
The wrapped line element preferably has a rectangular cross section. Copper or a copper alloy or also aluminum or an aluminum alloy is preferably used as the conductor material.

A cooling fluid can flow through this distance or free space between the relevant line element of a groove wall in order to absorb heat from the line element and / or from the laminated core forming the groove.
The invention is not limited to the use of a cooling fluid, but a respective projection or several projections can also serve to facilitate the assembly or arrangement of line elements within a groove, since the projections already support the assembly process in that the line elements can be positioned without damage.

The power-generating component according to the invention can in particular be a stator of an electric rotating machine, the present invention not being restricted to this application, but the power-generating component can also be the rotor of the electric rotating machine, which has turns of electrical line elements.

In an advantageous embodiment of the power-generating component it is provided that the line element has at least one second projection which extends radially in relation to the direction of longitudinal extent of the line element and which rests against at least one adjacent line element and consequently the line element at least on a section, on which the second projection is arranged, is positioned at a distance from the adjacent conduit element.

A cooling fluid can flow through this distance or free space between the relevant line element and an adjacent line element in order to absorb heat from the line element and / or from the laminated core forming the groove. Adjacent line elements can also be components of a common conductor which, in its winding in the groove, has line elements that run essentially parallel to one another and form sections of the conductor.
The spacing of the line elements from one another by means of the second projections also reduces the risk of damage to the line elements from one another, so that an insulating paper used between the line elements and the groove wall can be dispensed with.

The line element and the respective adjacent line element can be arranged adjacent to one another in the radial direction. This means that in a respective groove the line elements are positioned parallel to one another in a row arrangement along the radial direction of extent of the groove.
An alternative embodiment provides that the line element and the respective adjacent line element are arranged adjacent to one another in the circumferential direction.
Such a configuration requires a wider groove than in the first-mentioned embodiment. Furthermore, it is not ruled out that the power-generating component has both types of arrangement in a groove, that is to say has line elements which are adjacent to further line elements both in the radial direction and in the circumferential direction.

In particular, it is provided that a respective projection is an integral part of the line element, in particular one that cannot be separated from a coating or insulation of the line element.

For example, the line element can have a coating that forms the projection. This coating can be implemented in the form of a sheathing of the conductive material of the line element, in particular in order to form an insulation of the conductive material.
The insulation layer is used for electrical insulation of the line element. Materials from the group of thermoplastics and thermosets are preferably used here. In addition, the use of inorganic substances for insulation cannot be ruled out.

In an alternative embodiment it is provided that the projection or the thickening is formed by the conductive material of the line element and is covered by a coating or insulation of constant thickness.

In a further alternative embodiment it is provided that at least one projection is produced by deforming a section of the line element with a constant thickness.
This means that in this embodiment the projection is formed by a concavity which is produced by deformation of the line element, the concavity being formed in a section of the line element with a substantially constant cross section and the concavity being a convexity on its side opposite the concave side trains.
If necessary, a projection can also be formed by applying a solid or pasty medium such as adhesive dots, for example, which then hardens.
It is also possible to provide existing plastic knobs on the outside of the line element with a coating of an adhesive.

A projection can be formed by an essentially punctiform widening of the cross section of the line element.
In a further embodiment variant, a projection is formed by a cross-sectional widening of the line element extending along a length section of the line element.
In the first-mentioned case, the projection is thus formed by a compact elevation or thickening.
In the second case, the projection is formed by an elevation or thickening that extends over a length of the line element which is at least three times as long as the maximum transverse extent of the line element, measured in an area in which no projection is arranged.
When the line element runs in several grooves, a continuous or elongated projection can rest on the walls of several grooves.

Furthermore, first projections can be arranged on mutually opposite sides of the conduit element, so that the conduit element is supported on mutually opposite groove walls on mutually opposite sides.
A slight clearance fit between the first projections and the groove walls can also be implemented here. In general, however, the radial extension of the first projections should be dimensioned in relation to the clear width of the relevant groove in such a way that the with the electric rotary machine equipped with the power-generating component, the line element in question is positioned in the groove in a defined manner and is fixed in its translational degree of freedom perpendicular to the direction of longitudinal extent.

In one embodiment it is provided that between adjacent line elements at least one projection is arranged, which is positioned at least in some areas, in particular essentially, outside of two planes between which the adjacent line elements are arranged.

In this case, the second projection separates a respective line element from an adjacent line element. Furthermore, in this embodiment it can also be provided that the second projection here also realizes the function of spacing from a respective groove wall. In the case of essentially rectangular cross-sections of the line elements, this means that the second projections are arranged in the corner regions of a respective line element in the cross-section of a winding set.

In particular, it can be provided that a projection is convex on its side facing away from the conductive material of the line element.
This convexity of the projection leads to a point-like or linear support and thus counteracts an unnecessary narrowing of the free flow cross-section in a relevant groove.

In particular, projections on radially opposite sides of a line element can have different axial positions.

This means that no first projection is arranged at the axial position of a first projection between a first groove wall and a line element between this line element and an opposing second groove wall.

With regard to the second projections, this means that at the axial position of a second projection between a line element and a line element adjacent to the line element, no second projection is arranged between the adjacent line element and a third line element again arranged adjacent to the adjacent line element.
The axial positions of the projections on opposite sides of a line element should be at least 10 mm to 50 mm apart. The distance between the projections should expediently be defined in such a way that no bending of the line element can be recorded.

In an advantageous embodiment of the power-generating component it is provided that the power-generating component has a connection for feeding a cooling fluid into the groove.
It is advisable that the power-generating component then also has a flow connection for discharging the cooling fluid from the relevant groove.

A respective line element and the width of a respective groove can be dimensioned in relation to one another in such a way that the distance between a line element and a groove wall corresponds to a maximum of 1/10 of the maximum transverse extent of the line element at this axial position.

The distance here is the shortest distance between the groove wall and a region of the surface of the line element on which no first projection is arranged.
Likewise, the maximum transverse extent is to be determined at a position of the line element at which no projection is arranged.
This enables a large cross section of the line element for a high degree of copper filling and a low ohmic resistance within the groove. At the same time, the contact area between the remaining surface of the line element and the cooling fluid is maximized, while ensuring a sufficiently large cross section to achieve the lowest possible pressure loss.

Another aspect of the present invention is an electric rotary machine which has at least one power-generating component according to the invention.
In an advantageous embodiment, the electric rotary machine comprises a cooling fluid circuit which is fluidically coupled to the connection for supplying a cooling fluid to the power-generating component.

• 1: ein Ausschnitt aus einer Querschnitt-Ansicht einer erfindungsgemäßen leistungserzeugenden Komponente einer ersten Ausführungsform;
• 2: ein Ausschnitt aus einer Querschnitt-Ansicht einer erfindungsgemäßen leistungserzeugenden Komponente einer zweiten Ausführungsform;
• 3: ein Ausschnitt aus einer Querschnitt-Ansicht einer erfindungsgemäßen leistungserzeugenden Komponente einer dritten Ausführungsform;
• 4: ein Ausschnitt aus einer Querschnitt-Ansicht einer erfindungsgemäßen leistungserzeugenden Komponente einer vierten Ausführungsform; und
• 5: ein Ausschnitt aus einem Längsschnitt einer erfindungsgemäßen leistungserzeugenden Komponente.

The invention described above is explained in detail below against the relevant technical background with reference to the accompanying drawings, which show preferred embodiments. The invention is in no way restricted by the purely schematic drawings, it being noted that the exemplary embodiments shown in the drawings are not restricted to the dimensions shown. It is shown in

• 1 : a detail from a cross-sectional view of a power-generating component according to the invention of a first embodiment;
• 2 : a detail from a cross-sectional view of a power-generating component according to the invention of a second embodiment;
• 3 : a detail from a cross-sectional view of a power-generating component according to the invention of a third embodiment;
• 4th : a detail from a cross-sectional view of a power-generating component according to the invention of a fourth embodiment; and
• 5 : a detail from a longitudinal section of a power-generating component according to the invention.

First, the in the 1-4 different embodiments of the power-generating component shown.
The power-generating device 1 is here a stator of an electric rotating machine.
The power-generating component 1 has grooves running in the radial direction 10 on where as winding 2 several power elements arranged parallel to one another 20th are arranged. These line elements 20th can in particular be part of a common conductor.
On the radially inner side of the power-generating component 1 is used to seal off the groove 10 formed space a slot closure part 12th arranged.

The line elements 20th each have a coating 21 on, which can be designed in particular as an insulation layer.
At least some of the ones in the groove in question 10 arranged line elements 20th have a plurality of first projections arranged on their outside 22nd on the outside of the conduit element 20th of one the groove 10 limiting groove wall 11 spaced.
From the 1 and 2 it can be seen that these first protrusions 22nd are arranged at different axial positions, assuming that the
1 and 2 Sectional representations at different axial positions of the power-generating component 1 demonstrate.
Due to the arrangement of the first protrusions 22nd it is possible to use the pipe elements 20th In one winding process, gentle on the material in the slot 10 to place without the need for intermediate layers of insulation paper.
Furthermore, through a respective first projection 22nd a distance 30th between the line element 20th and the opposite groove wall 11 realized, which allows a cooling fluid in the groove 10 on the pipe element 20th can flow along and heat from the conduit element 20th can accommodate. Due to a preferred crowning or convexity 24 of the first protrusions 22nd is the contact surface between a respective first projection 22nd and the groove wall 11 minimized, so that correspondingly more volume for the cooling fluid 31 is available, and thus the distance between the line element 20th and groove wall 11 can be minimized.

As from the 3 and 4th can be seen on the line elements 20th in addition to the first protrusions 22nd still second protrusions 23 be arranged that a distance 41 between the relevant line element 20th and a respective adjacent line element 40 guarantee.
Accordingly, this configuration enables the cooling fluid 31 between the line elements 20th , 40 can be performed and such the line elements 20th , 40 almost completely with cooling fluid on all sides 31 can be flowed around.
4th shows a special embodiment in the case of the projections here both between the line elements 20th as well as between a respective line element 20th and the groove wall 11 are arranged. These projections thus have the function of a first projection 22nd and a second protrusion 23 . The line elements 20th are in the relevant groove 10 between a first level 50 and a second level 51 arranged. The said projections with the function of the first projection 22nd and the function of the second protrusion 23 are thus in the embodiment shown here essentially outside of these two levels 50 , 51 arranged in limited space.

The ones in the 1-4 illustrated projections 22nd , 23 are not necessarily executed selectively, but they can extend over a certain length on the outside of the relevant line element 20th , 40 extend.

5 shows in a longitudinal section also the through several line elements 20th realized winding of the power-generating component.
Here it can be seen that at the axial position of a second protrusion 23 between a line element 20th and one to the conduit element 20th adjacent line element 40 between the adjacent line element 40 and one to the adjacent line element 40 again adjacently arranged third line element 42 no second lead 23 is arranged. This enables the cooling fluid 31 the line elements can also better flow around transversely, deviating from a pure longitudinal flow.

With the power-generating component proposed here and with it Equipped electrical rotary machine devices are made available which, in a cost-effective and space-saving design, allow optimal cooling and / or a long service life or simplified assembly of their electrical lines or windings.

List of reference symbols

1

Power-generating component

2

Winding

10

Groove

11

Groove wall

12th

Slot closure part

20th

Line element

21

Coating

22nd

first lead

23

second lead

24

convexity

30th

distance

31

Cooling fluid

40

adjacent line element

41

Distance to the neighboring pipe element

42

third line element

43

axial distance between protrusions

50

First floor

51

second level

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 112011103347 T5 [0005]
• EP 3157138 A1 [0006]
• DE 102015013018 A1 [0008]
• JP 2016149900 A2 [0008]
• DE 102015220852 A1 [0009]
• DE 102016101705 A1 [0010]
• US 2017104380 AA [0010]
• US 2009078448 AA [0011]

Claims (11)

Power-generating component (1) of an electric rotary machine, comprising at least one winding (2) of at least one electrical conduction element (20) guided at least in sections in slots (10) of the power-generating component (1), characterized in that the conduction element (20) has at least one has a first projection (22) which extends radially in relation to the direction of longitudinal extent of the line element (20), the first projection (22) resting against a groove wall (11) delimiting a groove (10) and consequently the line element (20) at least on a section, on which the first projection (22) is arranged, is positioned by the first projection (22) at a distance (30) from the groove wall (11). Power-generating component according to Claim 1 , characterized in that the conduit element (20) has at least one second projection (23) which extends radially in relation to the direction of longitudinal extent of the conduit element (20) and which rests on at least one adjacently positioned conduit element (40) and consequently the conduit element (20) at least is positioned at a section on which the second projection (23) is arranged at a distance (41) from the adjacent line element (40). Power-generating component according to Claim 2 , characterized in that the line element (20) and the adjacent line element (40) i) in the radial direction, or ii) in the circumferential direction are arranged next to one another. Power-generating component according to one of the preceding claims, characterized in that the line element (20) has a coating (21) which forms the projection (22, 23). Power-generating component according to one of the preceding claims, characterized in that the projection (22, 23) i) forms an essentially punctiform cross-sectional widening of the line element (20), or ii) a cross-sectional widening of the line element extending along a length section of the line element (20) (20) trains. Power-generating component according to one of the preceding claims, characterized in that first projections (22) are arranged on opposite sides of the line element (20) so that the line element (20) is supported on opposite sides on mutually opposite groove walls (11). Power-generating component according to one of the Claims 2 until 5 , characterized in that between adjacent line elements (20, 40) at least one projection (22, 23) is arranged, which at least regionally, in particular essentially, outside of two planes (50, 51), between which the adjacent line elements (20, 40) are arranged, is positioned. Power-generating component according to one of the preceding claims, characterized in that projections on radially opposite sides of a line element have different axial positions. Power-generating component according to one of the preceding claims, characterized in that the power-generating component (1) has a connection for feeding a cooling fluid (31) into the groove (10). Power-generating component according to one of the preceding claims, characterized in that the distance (30) between a line element (20) and a groove wall (11) corresponds to a maximum of 1/10 of the maximum transverse extent of the line element (20) at this axial position. Electric rotary machine, comprising at least one power-generating component (1) according to one of the Claims 1 until 10 .

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