Stator of an electric machine

Abstract

Proposed is a stator of an electric machine (2), having a stator axis (3) and a stator laminated core (4) on which stator teeth (5) and stator grooves (6) situated between the stator teeth (5) are formed and which comprises a stator yoke (7) which connects the stator teeth (5), wherein: the stator grooves (6) have groove slots (7) formed between tooth ends (5e) facing away from the yoke; a single conductor (9) or a conductor bundle (10) comprising a plurality of conductors (9), in particular a stack of flat-wire conductors, is provided in each of the stator grooves (6) to form an electrical stator winding (11); and at least one groove gap (12) is provided between the groove flanks (6f) of each stator groove (6) and the conductor (9) or conductor bundle (10) arranged in the stator groove (6), which groove gap forms a groove gap channel (15) which extends in the axial direction with respect to the stator axis (3) and through which a cooling fluid, in particular oil, can flow along a groove cooling path (16); characterized in that - at least one supply path (17) is formed in the stator laminated core (4), which opens into at least one of the stator grooves (6) in order to supply cooling fluid to at least one groove cooling path (16), and - each supply path (17) extends through a distributor channel (18) which extends in the circumferential direction in the stator yoke (7), and a plurality of branch channels (19) branch off from said distributor channel and each open into one of the stator grooves (6).

Description

[0001] Description

[0002] title

[0003] Stator of an electrical machine

[0004] State of the art

[0005] The invention is based on a stator of an electrical machine according to the preamble of the main claim.

[0006] A stator of an electrical machine is already known from DE102019113785 A1, which has a stator axis and a stator laminated core. Stator teeth and stator slots located between the stator teeth are formed on the stator laminated core. The stator laminated core comprises a stator yoke connecting the stator teeth. The stator slots have slot slots formed between the tooth ends facing away from the yoke. A single conductor or a conductor bundle comprising several conductors, in particular a stack of flat wire conductors, is provided in each of the stator slots to form an electrical stator winding. Between the slot flanks of the respective stator slot and the conductor or conductor bundle arranged in the stator slot, at least one slot gap is provided, which forms a slot gap channel extending in the axial direction with respect to the stator axis. A cooling fluid, in particular oil, can flow through the slot gap channel along a slot cooling path.

[0007] Advantages of the invention

[0008] The stator of an electrical machine according to the invention, with the characterizing features of the main claim, has the advantage that the supply of the cooling fluid into the slot gap channels is simplified. The manufacturing costs for the stator are thereby reduced.

[0009] This is achieved according to the invention in that at least one supply path is formed in the stator laminated core, which opens into at least one of the stator slots for the cooling fluid supply of at least one slot cooling path, wherein the respective supply path runs through a distribution channel running in the circumferential direction in the stator yoke, from which a plurality of branch channels branch off, each of which opens into one of the stator slots.

[0010] The measures listed in the subclaims enable advantageous further developments and improvements of the stator of the electrical machine specified in the main claim.

[0011] It is very advantageous if the distribution channel and the branch channels are implemented exclusively in special laminations of the stator laminated core, which are arranged between two first sub-packages of the stator laminated core. The first sub-packages are formed from laminations that are, in particular, identical in shape and do not include a distribution channel or branch channels. Since the distribution channel and the branch channels are only implemented in the special laminations between the first sub-packages and not in all laminations of the stator laminated core, the electromagnetic properties of the stator laminated core are only minimally impaired.

[0012] It is particularly advantageous if the special laminations each have a plurality of distribution channel sections arranged one behind the other in the circumferential direction and spaced apart from one another, with an interrupter web being formed between adjacent distribution channel sections of the same special lamination. The distribution channel sections of at least two adjacent special laminations are arranged offset from one another in the circumferential direction and are fluidly connected to one or more distribution channels by partial overlap of distribution channel sections. This easily forms at least one distribution channel running in the circumferential direction in the stator yoke of the stator core.

[0013] It is further advantageous if the branch channels of the respective special plate each extend radially into one of the interrupter webs of the special plate, wherein the branch channels, for flow connection to the associated distributor channel, each overlap with one of the distributor channel sections of an adjacent special plate by providing a first overlap surface. In this way, the branch channels can be fluidly connected to the respective distributor channel to form the supply paths. The respective first overlap surface represents an inlet into the respective branch channel. According to a first embodiment, the respective branch channel can open into a groove base of the respective stator groove.

[0014] According to an advantageous second embodiment, the respective branch channel can extend into one of the laminar teeth of the respective special lamina and, to open into one of the stator slots, overlap with a branch channel outlet formed in the laminar tooth of an adjacent special lamina by providing a second overlap surface. In this way, the branch channel opens into a slot of the respective stator slot. The respective second overlap surface represents an outlet from the respective branch channel and an inlet into the respective stator slot.

[0015] It is furthermore advantageous if the first and / or second overlapping surfaces for the branch channels of the same distribution channel are of different sizes depending on the distance from an inlet into the distribution channel, in particular becoming increasingly larger with increasing distance. In this way, the cooling fluid from the respective distribution channel is distributed more evenly among the individual branch channels than with overlapping surfaces of the same size, whereby the stator slots or their slot gap channels are supplied with cooling fluid more evenly. In addition, the overlapping surfaces can be used to throttle the flow upstream of the slot gap channels. The flow throttling upstream of the slot gap channels has the advantage that it does not increase the pressure in the slot gap channels and thus does not place greater pressure loads on the at least one slot closure for sealing or quasi-sealing the slot slots.

[0016] Alternatively, a channel width of the branch channels of the same distribution channel, measured in the circumferential direction, can be designed to be of different sizes depending on the distance from the inlet into the distribution channel, in particular becoming increasingly larger with increasing distance.

[0017] It is also advantageous if one or more distribution channels, in particular several separate, partially annular distribution channels, are formed in the special fins. With several separate distribution channels, the cooling fluid can be distributed more evenly among the groove gap channels, thereby ensuring a more even supply of cooling fluid to the groove gap channels.It is also advantageous if the stator laminated core has a plurality of through-holes arranged along the circumferential direction for the passage of a fastening screw for fastening the stator laminated core to a housing, wherein an angular distance is provided between adjacent through-holes, wherein the respective distribution channel leads upstream via a connection channel formed in the special laminations into one of the through-holes, which can be flowed through by the cooling medium as part of the supply path, in particular by providing a groove running in the axial direction through the through-hole. In this way, the distribution channel can be supplied with cooling fluid via one of the through-holes of the stator laminated core. In this way, the through-holes can be used not only for fastening the stator laminated core to a housing, but also for supplying fluid to the stator slots.Preferably, the through holes are arranged in such a way that the through holes can be aligned with one another with at least one axis of symmetry. This allows the special lamellas to be rotated relative to one another by an angular distance equal to n times their respective angular distance.

[0018] It is advantageous if the respective special lamination has through-openings, each of which is part of one of the through-holes of the stator laminated core and each of which opens into one of the distribution channel sections of the special lamination via a connection channel of the special lamination. In this way, the through-holes of the stator laminated core can be fluidically connected to the respective distribution channel. The connection channel provided in the special lamination can be designed, for example, as a slot-shaped recess or punched-out portion.

[0019] It is very advantageous if, in order to achieve the overlap of distribution channel sections, several of the special laminations can be rotated relative to one another around the stator axis by a first angle of rotation, which is in particular an n-fold, especially in particular an odd n-fold angular distance, where n is a natural number. Alternatively or additionally, several of the special laminations can be arranged laterally reversed to one another in order to achieve the overlap of distribution channel sections. In this way, a package of special laminations can be formed with only one type or with only a few types of special laminations, in which the at least one distribution channel is designed according to the invention. The manufacturing costs for producing the stator laminated core are thereby reduced.It is also advantageous if two slot cooling paths running in opposite directions are provided in the respective stator slot, which exit at the ends of the respective stator slot via a slot outlet, particularly in the slot base or slot slot. This flow guidance in the respective stator slot requires a lower pressure in the respective slot cooling path, thus reducing the sealing requirements for the slot gap channels. Furthermore, the pressure loss in the respective slot cooling path is reduced because the respective slot cooling path does not run over the entire length, but only over an axial section of the respective stator slot.

[0020] It is also advantageous if the slot slots of the stator core are closed by at least one slot seal. This seals or virtually seals the slot gap channels at the slot slots, so that no cooling fluid, or only a small amount of cooling fluid, enters the air gap formed between the stator and a rotor of the electric machine.

[0021] The invention further relates to an electrical machine with a stator according to the invention.

[0022] drawing

[0023] Embodiments of the invention are shown in simplified form in the drawing and explained in more detail in the following description.

[0024] They show:

[0025] Fig.1 shows a stator with a supply path according to the invention according to a first embodiment,

[0026] Fig.2 one of the special lamellas according to the invention of the stator according to Fig.1 for forming the supply path according to the invention according to the first embodiment,

[0027] Fig.3 is a partial view of several stacked special lamellas according to Fig.2 for forming the supply path according to the first embodiment, Fig.4 is one of the special lamellas according to the invention of the stator according to Fig.1 for

[0028] Formation of the supply path according to the invention according to a second embodiment,

[0029] Fig.5 is a partial view of several stacked special lamellas according to Fig.4 for forming the supply path according to the second embodiment, Fig.6 is a partial view of a machine housing with a stator attached thereto according to Fig.1,

[0030] Fig.7 one of the base laminations for forming the first sub-packets of the stator according to Fig.1 and

[0031] Fig.8 a section through one of the stator slots of the stator according to Fig.1 with two

[0032] Supply path supplied groove cooling paths.

[0033] Description of the embodiments

[0034] Fig.1 shows a cut-open stator with a supply path according to the invention according to a first embodiment.

[0035] The stator 1 of an electrical machine 2 has a stator axis 3 and a stator laminated core 4 formed by a core of laminated laminations 20.

[0036] Stator teeth 5 and stator slots 6 located between the stator teeth 5 are formed on the stator laminated core 4. The stator laminated core 4 further comprises a stator yoke 7 connecting the stator teeth 5. The stator slots 6 have slot slots 6s formed between tooth ends 5e facing away from the yoke.

[0037] In each of the stator slots 6, a single conductor 9 or a conductor bundle 10 comprising several conductors 9, in particular a stack of flat wire conductors, is provided to form an electrical stator winding 11. Between the slot flanks 6f of the respective stator slot 6 and the conductor 9 or conductor bundle 10 arranged in the stator slot 6, at least one slot gap 12 is provided, which forms a slot gap channel 15 extending in the axial direction with respect to the stator axis 3. A cooling fluid, in particular oil, can flow through the respective slot gap channel 15 along a slot cooling path 16. The slot slots 6s of the stator laminated core 4 are sealed or quasi-sealed by at least one slot closure 34. The slot closure 34 can, for example, be a sealing sleeve, a slot closure unit, or an insert.

[0038] According to the invention, at least one supply path 17 is formed in the stator laminated core 4, which supply path opens into at least one of the stator slots 6 for supplying cooling fluid to at least one slot cooling path 16.

[0039] Furthermore, it is provided according to the invention that the respective supply path 17 runs through a distribution channel 18 running in the circumferential direction in the stator yoke 7, from which several branch channels 19 branch off, each of which opens into one of the stator slots 6.

[0040] The distribution channel 18 and the branch channels 19 are formed exclusively in a stack 21 of special laminations 20s of the stator core 4, which is arranged between two first sub-packages 4.1 of the stator core 4. The two first sub-packages 4.1 of the stator core 4 are formed, for example, by base laminations 20b, which are, in particular, identical in shape. One of the base laminations 20b is shown in Fig. 7.

[0041] In the stack 21 of special lamellae 20s, one or more distribution channels 18, in particular several separate, partially annular distribution channels 18, can be formed.

[0042] The special laminations 20s of the stack 21 are, for example, firmly connected to the two first sub-packets 4.1, so that a coherent stator laminated core 4 is formed.

[0043] In the stator slots 6, a plurality of support points, spaced apart from one another in the axial direction, can be formed for clamping the conductor 9 or conductor bundle 10 located in the respective stator slot 6. The support points are each formed by rotating a plurality of laminations 20 of the stator core 4 by a second angle of rotation t|, in particular by rotating a plurality of laminations 20 in opposite directions. The support points allow the slot gap channel 15 in each stator slot 6 to be reproducibly adjusted and stably maintained. The respective slot cooling path 16 can be at least narrowed at the support points. Therefore, a bypass can be provided at each support point to direct the cooling fluid past the respective narrowed support point.The bypasses of the respective stator slot 6 are formed, starting from the inlet into the respective stator slot 6 along the respective slot cooling path 16, alternately in the slot base 6g or in the slot slot 6s, in particular to form meandering slot cooling paths 16. In this way, the slot gap channels 15 can be flowed through in a meandering manner or the slot cooling paths 16 can run in a meandering manner, whereby the conductors 9 in the stator slots 6 are cooled more evenly and thus the cooling of the stator 1 is improved.

[0044] Fig.2 shows one of the special lamellas according to the invention of the stator according to Fig.1 for forming the supply path according to the invention according to the first embodiment.

[0045] The special laminations 20s each have a plurality of distribution channel sections 18a arranged one behind the other in the circumferential direction and spaced apart from one another, with an interrupter bar 22 being formed between adjacent distribution channel sections 18a of the same special lamination 20s. Furthermore, the special laminations 20s have a plurality of branch channels 19. The distribution channel sections 18a and the branch channels 19 together form a recess pattern in the respective special lamination 20s for forming the supply path 17 according to the invention. The number of branch channels 19 per special lamination 20s is smaller than the number of stator slots 6. Between adjacent branch channels 19, there can be one or more stator slots 6 that do not have a branch channel 19. The recess pattern can have at least one axis of symmetry.

[0046] Fig.3 shows a partial view of several stacked special lamellas according to Fig.2 for forming the supply path according to the first embodiment.

[0047] The distribution channel sections 18a of at least two adjacent special lamellae 20s of the stack 21 are offset from one another in the circumferential direction and are fluidly connected to one or more distribution channels 18 by partial overlap 24 of distribution channel sections 18a.

[0048] The branch channels 19 of the respective special lamella 20s extend radially relative to the stator axis 3 into one of the interrupter webs 22 of the special lamella 20s (Fig. 2, Fig. 3). For flow connection with the associated distributor channel 18, the branch channels 19 each overlap with one of the distributor channel sections 18a of an adjacent special lamella 20s by providing a first overlap surface 25 (Fig. 3). According to the first embodiment, the respective branch channel 19 opens into a groove base 6g of the respective stator groove 6.

[0049] The first overlapping surfaces 25 can be designed to be of different sizes for the branch channels 19 of the same distribution channel 18 depending on the distance from an inlet 18i into the distribution channel 18, in particular increasingly larger with increasing distance.

[0050] Alternatively, a channel width B of the branch channels 19 of the same distribution channel 18 measured in the circumferential direction can be designed to be of different sizes depending on the distance from the inlet 18i into the distribution channel 18, in particular becoming increasingly larger with increasing distance.

[0051] Fig.4 shows one of the special lamellas according to the invention of the stator according to Fig.1 for forming the supply path according to the invention according to a second embodiment.

[0052] The second embodiment differs from the first embodiment in that the respective branch channel 19 extends into one of the lamella teeth 30 of the respective special lamella 20s.

[0053] The recess pattern according to the second embodiment comprises the distribution channel sections 18a, the branch channels 19, and additional branch channel outlets 19a. The branch channels 19 and the branch channel outlets 19a are formed in different lamella teeth 30. The number of branch channels 19 per special lamella 20s is smaller than the number of lamella teeth 30. For example, one branch channel 19 is provided in one part of the lamella teeth 30, and one branch channel outlet 19a is provided in another part of the lamella teeth 30.

[0054] Fig.5 shows a partial view of several stacked special lamellas according to Fig.4 for forming the supply path according to the second embodiment.

[0055] The respective branch channel 19 overlaps, at the opening into one of the stator slots 6, with a branch channel outlet 19a formed in the lamella tooth 30 of an adjacent special lamella 20s by providing a second overlapping surface 26. According to the second exemplary embodiment, the first and / or second overlapping surfaces 25, 26 for the branch channels 19 of the same distribution channel 18 can be of different sizes depending on the distance from the inlet 18i into the distribution channel 18, in particular becoming increasingly larger with increasing distance.

[0056] Fig.6 shows a partial view of a machine housing with a stator attached thereto according to Fig.1.

[0057] The stator laminated core 4 according to the invention has at least one through-hole 28, in particular a plurality of through-holes 28 arranged along the circumferential direction, which are formed by corresponding through-openings 27 in the laminations 20 and are in particular each provided for passing through a fastening screw 29 for fastening the stator laminated core 4 to a machine housing 31. An angular distance a is provided between adjacent through-holes 28.

[0058] The respective through-hole 28 is provided radially outside the distribution channel 18 and is arranged, for example, at least in sections in a bulge formed on the outer circumference of the stator laminated core.

[0059] The respective distribution channel 18 leads upstream into one of the through-holes 28 via a connecting channel 23 formed in the special lamellae 20s and extending in particular in the radial direction. The respective through-hole 28, as part of the supply path 17, can be flowed through by the cooling medium, in particular by providing a groove extending in the axial direction through the through-hole 28. For example, a partially annular distribution channel 18 is provided in the stack 21 of special lamellae 20s for each through-hole 28.

[0060] According to Fig.2 and Fig.4, the respective through-opening 27 of the respective special lamella 20s opens into one of the distribution channel sections 18a of the special lamella 20s via the connecting channel 23 of the special lamella 20s. The connecting channel 23 of an individual special lamella 20s leads into one of the distribution channel sections 18a of the special lamella 20s, forming an angled, in particular L- or T-shaped, channel section.

[0061] To achieve the overlap 24 of distribution channel shown in Fig.3 and Fig.5

[0062] In sections 18a, several of the special lamellae 20s can be rotated relative to each other with respect to the stator axis 3 by a first angle of rotation, which is in particular an n-fold, especially an odd n-fold angular distance a, where n is a natural number. Alternatively or additionally, several of the special lamellae 20s can be arranged laterally inverted relative to each other.

[0063] Fig.8 shows a section through one of the stator slots of the stator according to Fig.1 with two slot cooling paths supplied by the supply path.

[0064] In the respective stator slot 6, two slot cooling paths 16 are provided, which run in opposite directions and are connected at the ends of the respective stator slot 6 via a slot

[0065] Drain, especially in the groove base 6g or in the groove slot 6s.

Claims

Claims 1. Stator of an electrical machine (2) with a stator axis (3) and with a stator laminated core (4) on which stator teeth (5) and stator slots (6) located between the stator teeth (5) are formed and which comprises a stator yoke (7) connecting the stator teeth (5), wherein the stator slots (6) have slot slots (7) formed between the tooth ends (5e) facing away from the yoke, wherein a single conductor (9) or a conductor bundle (10) comprising a plurality of conductors (9), in particular a stack of flat wire conductors, is provided in each of the stator slots (6) to form an electrical stator winding (11), wherein between the slot flanks (6f) of the respective stator slot (6) and the conductor (9) or the conductor bundle (10) arranged in the stator slot (6)conductor bundle (10) at least one slot gap (12) is provided, which forms a slot gap channel (15) extending in the axial direction with respect to the stator axis (3), through which a cooling fluid, in particular oil, can flow along a slot cooling path (16), characterized in that. - at least one supply path (17) is formed in the stator laminated core (4), which opens into at least one of the stator slots (6) for supplying cooling fluid to at least one slot cooling path (16), - the respective supply path (17) is connected by a conductor in the stator yoke (7) Circumferentially extending distribution channel (18), from which several branch channels (19) branch off, each of which opens into one of the stator slots (6).

2. Stator according to claim 1, characterized in that the distribution channel (18) and the branch channels (19) are designed exclusively in special laminations (20s) of the stator laminated core (4), which are arranged between two first partial packages (4.1) of the stator laminated core (4).

3. Stator according to claim 2, characterized in that the special laminations (20s) each have a plurality of distribution channel sections (18a) arranged one behind the other in the circumferential direction and spaced apart from one another, wherein an interrupter web (22) is formed between adjacent distribution channel sections (18a) of the same special lamination (20s), wherein the distribution channel sections (18a) of at least two adjacent special laminations (20s) are offset from one another in the circumferential direction and by partial overlapping (24) of distribution channel sections (18a) are flow-connected to one or more distribution channels (18).

4. Stator according to claim 3, characterized in that the branch channels (19) of the respective special lamella (20s) extend in the radial direction with respect to the stator axis (3) in each case into one of the interrupter webs (22) of the special lamella (20s), wherein the branch channels (19) for the flow connection with the associated distributor channel (18) each overlap with one of the distributor channel sections (18a) of an adjacent special lamella (20s) by providing a first overlapping surface (25).

5. Stator according to one of the preceding claims, characterized in that a. the respective branch channel (19) opens into a groove base (6g) of the respective stator groove (6), or b. the respective branch channel (19) extends into one of the laminar teeth (30) of the respective special lamina (20s) and, in order to open into one of the stator grooves (6), overlaps in each case with a branch channel outlet (19a) formed in the laminar tooth (30) of an adjacent special lamina (20s) by providing a second overlapping surface (26).

6. Stator according to one of claims 4 or 5, characterized in that the first and / or second overlapping surfaces (25, 26) for the branch channels (19) of the same distribution channel (18) are of different sizes depending on the distance from an inlet (18i) into the distribution channel (18), in particular are increasingly larger with increasing distance.

7. Stator according to one of claims 4 or 5, characterized in that a channel width (B) of the branch channels (19) of the same distribution channel (18) measured in the circumferential direction is of different sizes depending on the distance from an inlet (18i) into the distribution channel (18), in particular becoming increasingly larger with increasing distance.

8. Stator according to one of the preceding claims, characterized in that one or more distribution channels (18), in particular a plurality of partially annular distribution channels (18) separated from one another, are formed in the special lamellas (20s).

9. Stator according to one of the preceding claims, characterized in that the stator laminated core (4) has a plurality of through holes (28) arranged along the circumferential direction for the passage of a fastening screw (29) for fastening the stator laminated core (4) to a housing (31), wherein an angular distance (a) is provided between adjacent through holes (28), wherein the respective distribution channel (18) leads upstream via a connection channel (23) formed in the special laminations (20s) into one of the through holes (28), which can be flowed through by the cooling medium as part of the supply path (17), in particular by providing a groove running in the axial direction through the through hole (28).

10. Stator according to claim 8, characterized in that the respective special lamination (20s) has through-openings (27), which are each part of one of the through-holes (28) of the stator laminated core (4) and each open into one of the distribution channel sections (18a) of the special lamination (20s) via a connection channel (23) of the special lamination (20s). 11 . Stator according to one of the preceding claims, characterized in that in order to achieve the overlap (24) of distribution channel sections (18a) a. several of the special lamellae (20s) are rotated relative to one another with respect to the stator axis (3) by a first angle of rotation, which is in particular an n-fold, especially in particular an odd n-fold angular distance (a), where n is a natural number, and / or b. several of the special lamellae (20s) are arranged laterally reversed to one another.

12. Stator according to one of the preceding claims, characterized in that in the respective stator groove (6) two groove cooling paths (16) running in opposite directions are provided, which exit at the ends of the respective stator groove (6) via a groove outlet, in particular in the groove base (6g) or in the groove slot (6s).

13. Stator according to one of the preceding claims, characterized in that the slot slots (6s) of the stator laminated core (4) are closed by means of at least one slot closure (34).

14. Electrical machine with a stator (1) according to one of the preceding claims.

Images