CN109936226A - Stator and motor with cooling system - Google Patents

Abstract

The present invention relates to a kind of stators (1) for being used for motor (2), it is with stator core (3), the stator core extends around the stator longitudinal axis (4) of stator (1) and along stator longitudinal axis (4), wherein, stator core (3) has multiple stator tooths (5), the stator tooth is distributed ground arrangement in the peripheral direction of stator (1) and extends towards stator longitudinal axis (4) and along stator longitudinal axis (4), wherein, it is configured with stator slot (6) respectively between adjacent stator tooth (5).The cooling duct wall portion (7) of stator (1) is so disposed between at least one stator slot (6) and stator tooth (5) adjacent at least one stator slot (6), so that construction is parallel to the cooling duct (8) of stator longitudinal axis (4) extension between cooling duct wall portion (7) and stator tooth (5).In addition, the present invention relates to a kind of motor (2), with such stator (1).

Description

Stator and motor with cooling system

technical field

The present invention relates to a coolable stator for an electric machine. Furthermore, the invention relates to an electric machine having a stator of this type.

Background technique

Electric machines usually have a rotor, which is surrounded by a stator. The stator has a stator base body (Statorrundkörper) or a stator core (Statorblech, sometimes also called a stator core) with stator teeth and stator slots, wherein the stator slots are arranged between the stator teeth. Arranged around the stator teeth and in the stator slots are stator windings, which are usually realized in the form of coils (spules) formed from insulated stranded wires. The coils each have a specific mass and a specific ohmic resistance, which is determined by the material, length and cross-section of the litz wires. The density of the stranded wire and the specific ohmic resistance are defined by the material. A coil part of the coil is arranged in the stator slot and thus forms the active part (aktiven Teil, sometimes also called excitation part) of the stator winding. The other coil part forms the winding head of the electric machine and is usually arranged on the axial end side of the electric machine. This coil part is also referred to as the winding head part. The power density of the electric machine depends on the configuration of the coils, in particular on the diameter of the litz wires and on the number of stator windings.

Power losses in the form of heat losses (Verlustwärme) occur during the operation of the electric machine. The power density of an electric drive depends in particular on the operating temperature of the motor and power electronics. Overheating of the electric machine (for example due to heat losses) leads to a reduction in the power density and may furthermore lead to permanent damage at the electric machine. For example, the insulation of the litz wires of the stator winding can be damaged by excessively high temperatures and thus cause short circuits between adjacent litz wires.

In order to avoid overheating and overheating, many electric machines have cooling devices for heat removal. Many different cooling devices or cooling systems are known, which are designed, for example, in particular for cooling a stator or a rotor. In the case of cooling devices for cooling the stator of an electric machine, a distinction is generally drawn between cooling devices for heat removal of the active parts of the stator windings and cooling devices for heat removal of the winding heads of the electric machine.

Known cooling devices for heat removal of the active part of the stator winding often have a cooling jacket with a cooling structure, which surrounds the stator. Therefore, the cooling jacket is arranged in the region of the stator back iron of the stator. The cooling is effected, for example, with water, oil, water-glycol-mixtures or the like. Here it is indirect cooling, since the cooling jacket has no direct contact with the stator windings. Cooling of the winding heads is mostly not achieved. Therefore, such a cooling device is particularly suitable for cooling electric machines with relatively small winding head parts, ie with a relatively large structural length. A disadvantage in the case of such cooling devices is the dissipation of heat losses from the stator windings through the electrical insulation of the stator slots, through the stator core and through the separating seam between the stator core and the cooling jacket towards the cooling fluid. Therefore, heat loss must overcome multiple thermal barriers or resistances. This leads to an additional limitation of the effective power (Leistungsfähigkeit) of the electric machine.

Heat-dissipating cooling devices for winding heads of electrical machines are often designed to spray the winding heads directly with fluid, in particular oil. In this way, direct cooling of the stator windings at the winding heads is achieved, wherein no cooling of the stator, in particular the stator core, is achieved. These cooling devices are therefore particularly suitable for cooling electrical machines with relatively high winding head sections, ie relatively short overall lengths.

From DE 10 2011 053 299 A1 a cooling system is known for an electric machine in which cooling channels are formed in the stator core radially along the stator teeth and between adjacent stator slots. The intertangent extends to the longitudinal axis of the stator. These cooling channels have the disadvantage that a relatively large area of the stator winding is thereby lost. Furthermore, inflow channels and outflow channels are provided in the stator back iron, whereby the power density of the electric machine is reduced.

The document DE 10 2011 056 007 A1 discloses a cooling system for an electric machine in which cooling plates with radially extending cooling channels are arranged between adjacent stator cores. Such a construction is very complex and can only be produced at a cost.

The document DE 10 2012 217 711 A1 describes an electric machine with a cooling system in which cooling channels with triangular cross-sections are formed in a potting compound surrounding the stator winding. Therefore, the cooling channel is arranged between the two stator tooth segments. Using such a cooling system does not ensure efficient cooling of the remaining stator areas.

An electrical machine is known from DE 10 2014 017 745 A1 in which a cooling device is arranged in a stator slot and closes the stator slot on one side. This electrical machine has the disadvantage that the number of stator windings and/or the size of the stator back iron is thereby significantly reduced.

SUMMARY OF THE INVENTION

The task of the present invention is therefore to obviate or at least partially obviate the disadvantages described above in the case of a stator for an electric machine and an electric machine. In particular, it is the task of the present invention to create a stator for an electric machine and an electric machine which is simple and cost-effective with a predetermined installation space and a predetermined power density Ensures improved cooling of the stator.

The above tasks are achieved by the patent claims. The object is therefore solved by a stator with the features of the independent claim 1 and by an electric machine with the features of the parallel claim 8 . Additional features and details of the invention emerge from the dependent claims, the description and the drawings. Here, the features and details described in connection with the stator according to the invention obviously also apply in connection with the electric machine according to the invention and respectively vice versa, so that mutual reference can always be made with regard to the disclosure for the individual inventive aspects.

According to a first aspect of the invention, this task is solved by a stator for an electric machine. The stator has a stator core which extends around and along the stator longitudinal axis of the stator. The stator core has a plurality of stator teeth which are distributed in the circumferential direction of the stator and extend towards and along the longitudinal axis of the stator. Stator slots are respectively formed between adjacent stator teeth. According to the invention, the cooling channel walls of the stator are arranged between the at least one stator slot and the stator teeth adjacent to the at least one stator slot in such a way that between the cooling channel walls and the stator teeth, parallel to the longitudinal direction of the stator is formed. Axial extending cooling channel.

The stator core is preferably made of electrical steel sheet (Elektroblech, also sometimes called electrical steel sheet) and preferably has an alloy of iron and silicon. Preferably, the electrical steel sheet is produced by cold rolling. The stator core is preferably composed of a large number of stator laminations which are connected to one another, in particular glued together and electrically insulated from one another, which are arranged coaxially. Preferably, the stator chips are glued to one another by means of a coating. Alternatively, the stator core can likewise be produced by means of an additive manufacturing method, wherein partial electrical insulation of the stator longitudinal axis section is preferred in order to avoid eddy currents passing through the stator.

The longitudinal axis of the stator preferably corresponds to the longitudinal axis of the rotor in the case of an installed rotor. The stator core extends around the stator longitudinal axis and has a central free space for accommodating the rotor in the region of the stator longitudinal axis. Accordingly, the cross-section of the stator core (except for the stator slots, cooling channels and the like) is preferably annular or substantially annular in configuration. Furthermore, the stator core extends along the stator longitudinal axis, so that the stator core (with the exception of the stator slots, cooling channels and the like) is preferably of hollow-cylindrical or substantially hollow-cylindrical configuration.

The stator teeth preferably extend towards the stator longitudinal axis by a common stator back iron via which the stator teeth are connected to each other and terminate in a central free space for accommodating the rotor. The stator teeth are preferably distributed regularly, in particular uniformly, in the circumferential direction of the stator. At the end facing the longitudinal axis of the stator, the stator teeth preferably have stator tooth heads which have a greater width than the rest of the stator teeth. The remaining areas of the stator teeth preferably have a constant or at least approximately constant width.

Stator slots with slot inner walls are formed between adjacent stator teeth. The stator slots are preferably produced by means of a dividing production method such as, for example, punching, laser cutting or the like. Preferably, a layer of adhesive or paint is arranged (in particular sprayed) on the inner wall of the groove for sealing. This is particularly advantageous in the case of stator cores that are assembled from stator core sheets that are not glued to one another.

The stator windings are preferably arranged in the stator slots, wherein the stator windings preferably have stranded conductors. A stranded line has a large number of individual wires, which are tightly bundled together by a common insulating jacket and thus insulated radially outwards. The individual wires are preferably twisted against each other. The stator windings in the stator slots preferably form the active part of the stator windings. The remaining stator windings arranged at the end faces of the stator preferably form winding heads.

The cooling channel walls preferably have a material with a particularly favorable or high thermal conductivity in order to improve or not unduly hinder the heat exchange between the cooling fluid (eg, water, oil or the like) and the stator windings. Preferably, the cooling channel wall is designed in one piece and can be moved into the stator core. Therefore, easy assemblability of the cooling channel wall is ensured. Furthermore, the cooling channel wall is preferably electrically insulated on the side facing the stator winding, in particular by means of an adhesive or varnish layer of insulating paper or the like. The insulation preferably also has a relatively high thermal conductivity in order to improve or not unduly hinder the heat exchange between the cooling fluid and the stator windings. Therefore, thinner layers of adhesive or lacquer are preferred as insulation for the cooling channel walls.

The cooling channel wall preferably surrounds the stator slot by a plurality of sides, so that the cooling channel is formed on the plurality of sides of the stator slot. Via the cooling channel walls, the cooling channels are preferably sealed relative to the stator slots, so as to avoid intrusion of cooling fluid into the stator slots. For this reason, it is preferred that the cooling channel is sealed relative to the stator core, eg, guided in grooves in the stator core and/or glued to the stator core or the like. According to the invention, the cooling channel can be divided into a plurality of cooling channels, which preferably extend parallel to one another along the longitudinal axis of the stator.

The stator windings are preferably arranged on the stator slots in such a way that the stator windings are supported on the cooling channel walls. Preferably, the stator slots are separated from the immediately adjacent stator teeth by means of annular or two separate cooling channel walls, so that the stator slots are surrounded on both sides of the cooling channel. Preferably, the ends of the stator slots facing the stator back iron are likewise delimited by cooling channel walls, so that cooling channels are formed between the stator back iron and the stator slots. It is preferred that the cooling channel walls are formed convexly or at least slightly convex towards the stator slots, in order to avoid bending of the cooling channel walls towards adjacent stator teeth when the stator windings are arranged in the stator slots. In this way, it can be ensured that the cooling ducts are not closed off or excessively narrowed when the stator windings are arranged.

The stator according to the invention has the advantage over conventional stators that cooling of the stator is provided in a simple and cost-effective manner, particularly close to the point of occurrence of heat losses in the stator, ie at the stator function at the windings. Only a few heat flow barriers are arranged between the stranded wire and the cooling medium of the cooling channel. In this way, the stator can be dissipated particularly efficiently and thus maintenance of the predetermined operating temperature can also be ensured in the case of particularly high loads. Furthermore, the additional cooling jacket can be dispensed with, so that the stator slot can be enlarged and the stator back iron can be guided further outwards in the radial direction from the stator longitudinal axis. Thereby, the power density of the stator can be increased. With the aid of the stator according to the invention, the power density and the efficiency of the electric machine can thus be significantly improved with a given installation space.

According to an advantageous development of the invention, in the case of the stator, it can be provided that between the cooling channel wall and the stator teeth at least one cooling channel wall relative to the stator teeth is arranged. The supporting support device. The support means are preferably designed to divide the cooling channel into a plurality of cooling channels. Preferably, the cooling channels are designed to flow through the cooling fluid independently of one another. Preferably, the cooling channel walls are supported against the stator teeth by means of a plurality of support means. The support means are preferably distributed in such a way that, when the stator windings are arranged at the cooling channel walls, a pressure distribution that is as uniform as possible is ensured. Preferably, the support means are fastened at the cooling channel wall or are at least partially constructed integrally with the cooling channel wall. The support means have the advantage that bending of the cooling channel walls towards the stator teeth is avoided, or at least substantially avoided, in the case of the arrangement of the stator windings in the stator slots.

It is preferred according to the invention that the support device has an electrical insulator or is designed as an electrical insulator. The electrical insulator is preferably arranged at least in the contact area of the support means with the adjacent stator teeth. As electrical insulators, for example, adhesives, lacquers, resins, ceramics or the like are preferred. By means of the electrical insulator, the electrical strength of the stator can be further improved.

Further preferably, the cooling channel wall has a U-shaped cross-section or at least a substantially U-shaped cross-section. The two legs of the cooling channel wall preferably extend parallel to each other, approximately in the direction of the longitudinal axis of the stator. The ends of the cooling channel walls adjacent to the longitudinal axis of the stator are preferably accommodated in grooves at the adjacent stator tooth heads and are sealed fluid-tight and preferably electrically insulating. In this way, the cooling channel wall can be fastened between the two stator teeth easily and with simple means. The cooling channels are therefore preferably open only to the end side of the stator and are otherwise hermetically sealed by the cooling fluid. Such a cooling channel wall has the advantage that it can be easily produced and can be assembled on the stator core, in particular by being inserted into the stator core. Furthermore, by means of a stator core constructed in this way, cooling channels can be provided which surround the stator slots and thus the stator windings on three sides. The U-shaped cross section has the advantage that a particularly efficient heat dissipation of the stator windings and an easy assembly can be achieved in this way.

In a particularly preferred embodiment of the invention, in the case of the stator, provision can be made that the cooling channel wall has a bulge in at least one partial section. The bulge is preferably formed in the direction of the indirectly adjacent stator teeth, so that in this subsection the side of the cooling channel wall facing the stator slots is concave and the side of the cooling channel wall facing the stator teeth is formed convexly . The bulge is preferably configured such that at least one stranded wire can be arranged in the bulge. Preferably, a plurality of stranded wires may be arranged within the protuberance. It is also preferred that the cooling channel wall has a plurality of such elevations, which are distributed in particular uniformly or regularly on the cooling channel wall. Furthermore, it is preferred that the cooling channel wall touches the adjacent stator teeth in the region of the bulge and thus forms the support means. This has the advantage that additional support means can be dispensed with. Preferably, the cooling channel walls are electrically insulated at the point of contact with the stator teeth. This bulge has the advantage that an increase in the contact surface between the cooling channel wall and the stator winding and between the cooling channel wall and the cooling fluid can thereby be achieved. In this way the heat transfer between the stranded wire and the cooling fluid and thus the cooling capacity of the stator can be improved.

It is preferred that the cooling channel wall has a zigzag or wavy cross section in at least one partial section. Preferably, the cooling channel walls contact adjacent stator teeth at the crests or peaks. It is preferred here that the cooling channel wall is electrically insulated at the point of contact. Such a cross section has the advantage that the cooling channel wall therefore has a larger surface for heat exchange between the stranded wire and the cooling fluid. In addition, such a cooling channel wall portion has high rigidity against bending. Furthermore, additional support means can be eliminated.

Preferably, the cooling channel wall is constructed integrally with the stator core. The cooling channel walls are preferably constructed by removal of electrical steel sheet material in the region of the cooling channel (eg by punching, laser cutting or the like). Alternatively, the stator core with cooling channel walls can be produced by means of an additive manufacturing method. Thus, a stator core with integrated cooling channels and integrated cooling channel walls can be produced with simple components and cost-effectively. Additional sealing of the cooling channel walls to the stator core is not required due to the overall construction.

According to a second aspect of the invention, this task is solved by an electric machine with a rotor and a stator surrounding the rotor, wherein the stator is designed as a stator according to the invention. The rotor is preferably constructed according to a conventional rotor of a conventional electric machine. Preferably, the rotor also has cooling channels for cooling the rotor directly.

The cooling channels of the stator can be charged with cooling fluid, for example, via a common cooling fluid supply of the electric machine. Furthermore, the electric machine preferably has a cooling fluid discharge via which cooling fluid can be discharged from a cooling channel of the electric machine. Alternatively, the electric machine for the cooling channels has separate cooling fluid supply lines and cooling fluid discharge lines, so that the individual cooling fluid channels can be loaded with cooling fluid independently of one another. By means of temperature sensors in the region of the cooling channels and suitable control electronics, a targeted heat removal of the stator can thus be achieved.

All the advantages already described for the stator according to the first aspect of the invention result in the case of the described electric machine. Thus, the electric machine according to the invention has the advantage over known electric machines that cooling of the stator is provided in a simple and cost-effective manner, particularly close to the point of occurrence of heat losses from the stator, That is, it works at the stator winding. Only a few heat flow barriers are arranged between the stranded wire and the cooling medium of the cooling channel. In this way, the stator can be dissipated particularly efficiently and thus the maintenance of the predetermined operating temperature of the electric machine can also be ensured in the case of particularly high loads. Furthermore, in the case of electric machines, the additional cooling jacket surrounding the stator can be dispensed with, so that the stator slots can be enlarged and the stator back iron can be further guided outwards in the radial direction by the stator longitudinal axis. As a result, the power density of the electric machine can be increased. The electric machine according to the invention has a significantly improved power density and a significantly increased efficiency, given a given installation space, compared to conventional electric machines with an alternative cooling system.

It is preferred that insulating paper is arranged on the side of the cooling channel wall facing the stator slots. The insulating paper provides electrical insulation of the cooling channel walls from the stator windings and increases the electrical strength of the electric machine in an advantageous manner and with simple means.

Preferably, the electric machine has a first end cover (Abschlussdeckel, sometimes also called a sealing cover) on at least one first end side, wherein the first end cover covers the stator in such a way that the cooling channel is sealed towards the first end side. Further preferably, the electric machine has a second end cover on the second end side, which covers the stator in such a way that the cooling channel is sealed towards the second end side. The first end cap preferably has an inflow for supplying the cooling fluid, wherein the inflow is connected in fluid communication with the cooling channel and is sealed against the surrounding environment. The second end cap preferably has an outflow for discharging the cooling fluid, wherein the outflow is connected in fluid communication with the cooling channel and is sealed against the surrounding environment. Alternatively, the first end cap has an inflow portion and an outflow portion. In this case it is preferred that the second end caps connect the cooling channels in fluid communication with each other and seal against the surrounding environment. The end cap is designed in such a way that the fluid flow through the electric machine can be guided by the inflow through the fluid channel towards the outflow, wherein escape of the cooling fluid within the electric machine is preferably avoided. Preferably, the end caps are configured as electrical insulators or at least electrically insulated with respect to the stator core and/or the stator windings.

Description of drawings

The stator according to the invention and the electric machine according to the invention are explained in more detail subsequently with the aid of drawings. Schematically, respectively:

FIG. 1 shows a part of an electric machine according to the prior art in a perspective view,

FIG. 2 shows a detail of a preferred first embodiment of the stator according to the invention in a top view,

Figure 3 shows an enlarged detail from Figure 2 in a top view,

FIG. 4 shows a portion of the first end side of the stator from FIG. 2 with a sealing device in a perspective view,

Figure 6 shows a detail of a preferred second embodiment of the stator according to the invention in a top view,

FIG. 7 shows a detail of a preferred third embodiment of the stator according to the invention in a top view,

FIG. 8 shows a preferred embodiment of the electric machine according to the invention in a side view.

Elements with the same function and operating principle are each provided with the same reference symbols in FIGS. 1 to 8 .

List of reference symbols

1 Stator

2 motors

3 stator core

4 Stator longitudinal axis

5 stator teeth

6 stator slots

7 Cooling channel wall

8 cooling channels

9 Support device

10 Uplift

11 Rotor

12 insulating paper

13 First end side

14 First end cap

15 Stator back iron

16 Cooling jacket

17 Stator winding

18 Winding head

19 Stator tooth head

20 holding slots

21 Seals

22 Second end side

23 Second end cap

24 Coolant inflow port

25 Coolant outflow connection.

Detailed ways

FIG. 1 schematically shows a part of an electric machine 2 according to the prior art in a perspective view. The electric machine 2 has a rotor 11 which is surrounded by the stator 1 . The stator 1 has a stator core 3 with a large number of stator slots 6 and a stator back iron 15 . Arranged in the stator slots 6 are stator windings 17 which form winding heads 18 outside the stator slots 6 . A cooling jacket 16 with a plurality of cooling channels 8 is arranged on the outer surface of the stator 1 which points away from the rotor 11 . Efficient cooling of the stator windings 17 , especially within the stator slots 6 , is not feasible with such an electric machine 2 .

FIG. 2 schematically shows a part of a preferred first embodiment of the stator 1 according to the invention in a top view. An enlarged detail from FIG. 2 is shown in FIG. 3 . The stator 1 has a stator core 3 with a plurality of stator teeth 5 and a stator back iron 15 connecting the stator teeth 5 . Stator slots 6 are respectively arranged between adjacent stator teeth 5 . Arranged between the stator slots 6 and the stator core 3 is a cooling channel wall 7 which is supported against the stator core 3 via a plurality of support means 9 . The cooling channel walls 7 are held in the receiving grooves 20 of two adjacent stator tooth heads 19 of the stator teeth 5 of the stator core 3 and are sealed against the stator core 3 . A plurality of cooling ducts 8 are formed between the cooling duct wall 7 and the stator core 3 , which cooling ducts are separated from one another by support means 9 . Alternatively, the cooling channels 8 can likewise be connected to each other in fluid communication or form a common cooling channel 8 . The cooling channel 8 is designed for the passage of a cooling fluid, such as, for example, water, oil or the like. Arranged in the stator slots 6 are stator windings 17 which are supported against the cooling channel walls 7 . An optional insulating paper 12 for electrical insulation is arranged between the cooling channel wall 7 and the stator winding 17 .

FIG. 4 schematically shows a portion of the first end face 13 of the stator 1 from FIG. 2 in a perspective view. An annular seal 21 is arranged in the region of the stator back iron 15 . Furthermore, a seal 21 is arranged on the end side of the cooling channel wall 7 . The seal 21 is configured for sealing with respect to the first end cover 14 (see FIG. 5 ), not shown here, in order to avoid unintentional escape of cooling fluid from the stator 1 .

FIG. 5 schematically shows the stator 1 from FIG. 4 with end caps 14 , 23 in a perspective view. A first end cover 14 is arranged on the first end side 13 of the stator core 3 and is sealed via a seal 21 . The coolant inflow port 24 is thus connected in fluid communication with the cooling channel 8 , which is hidden in this view, and is sealed against the surrounding environment. The second end cover 23 is arranged on the second end side 22 of the stator core 3 and is sealed via the seal 21 . The coolant outflow port 25 is thus connected in fluid communication with the cooling channel 8 , which is hidden in this view, and is sealed against the surrounding environment. Thus, the coolant inflow port 24 and the coolant outflow port 25 are connected to each other in fluid communication via the cooling channel 8 . The coolant inflow port 24 and the coolant outflow port 25 are preferably designed for connection to a coolant pump (not shown) with a coolant cooling device.

FIG. 6 schematically shows a part of a preferred second embodiment of the stator 1 according to the invention in a top view. The stator 1 of the second embodiment differs from the first embodiment substantially by the overall configuration of the stator core 3 , the cooling channel walls 7 and the support means 9 . Such a stator core 3 can be produced particularly easily and cost-effectively and enables a reduction in the number of assembly steps of the stator 1 , since additional assembly of the cooling channel wall 7 is eliminated.

FIG. 7 schematically depicts a fragment of a preferred third embodiment of the stator 1 according to the invention in a top view. The stator 1 of the third embodiment is substantially different from the first embodiment in the configuration of the cooling channel wall portion 7 . The cooling channel wall 7 has a corrugated shape with a plurality of elevations 10 , wherein the elevations 10 are configured to support the device 9 and the cooling channel wall 7 is supported against the stator core 3 . A part of the stator winding 17 is arranged in the ridges 10 , while another part of the stator winding 17 is arranged in the remaining area of the stator slot 6 . A cooling channel 8 is formed between the two bulges 10 and the stator core 3 .

FIG. 8 schematically shows a preferred embodiment of the electric machine 2 according to the invention in a side view. The electric machine 2 has a rotor 11 which is surrounded by the stator 1 according to the invention. The stator 1 and the rotor 11 are arranged coaxially to the stator longitudinal axis 4 . A coolant inflow connection 24 is arranged on the first end side 13 of the electric machine 2 . A coolant outflow port 25 is arranged on the second end side 22 of the electric machine 2 opposite the first end side 13 .

Claims (10)

1. one kind is used for the stator (1) of motor (2), which has stator core (3), and the stator core is around the stator (1) Stator longitudinal axis (4) and along the stator longitudinal axis (4) extend, wherein the stator core (3) have multiple stator tooths (5), the stator tooth ground arrangement is distributed in the peripheral direction of the stator (1) and towards the stator longitudinal axis (4) and Extend along the stator longitudinal axis (4), wherein it is configured with stator slot (6) respectively between adjacent stator tooth (5),

It is characterized in that,

It is so arranged between at least one stator slot (6) and stator tooth (5) adjacent at least one stator slot (6) There is the cooling duct wall portion (7) of the stator (1), so that the structure between the cooling duct wall portion (7) and the stator tooth (5) It makes and is parallel to the cooling duct (8) that the stator longitudinal axis (4) extends.

2. stator (1) according to claim 1, which is characterized in that in the cooling duct wall portion (7) and the stator tooth (5) at least one eyelid retractor for support of the cooling duct wall portion (7) relative to the stator tooth (5) is disposed between Part (9).

3. stator (1) according to claim 2, which is characterized in that the supporting device (9) has electrical insulator or construction At electrical insulator.

4. stator (1) according to any one of the preceding claims, which is characterized in that cooling duct wall portion (7) tool Have in the cross section of u shape or at least with the cross section for being substantially in u shape.

5. stator (1) according to any one of the preceding claims, which is characterized in that the cooling duct wall portion (7) exists There is protuberance (10) at least one portion section.

6. stator (1) according to claim 5, which is characterized in that the cooling duct wall portion (7) it is described at least one With the cross section or wavy cross section of indention in partial sector.

7. stator (1) according to any one of the preceding claims, which is characterized in that the cooling duct wall portion with it is described Stator core integrally constructs.

8. one kind has rotor (11) and surrounds the motor (2) of the stator (1) of the rotor (11), which is characterized in that described fixed Sub (1) is according to claim 1 to any one of 7 constructions.

9. motor (2) according to claim 8, which is characterized in that in the cooling duct wall portion (7) in face of described fixed Insulating paper (12) are disposed on the side of pilot trench (6).

10. motor (2) according to claim 8 or claim 9, which is characterized in that the motor (2) is at least one the first end side (13) there are first end cover (14) at, wherein the first end cover (14) so covers the stator (1), so that the cooling Channel (8) is sealed towards first end side (13).