Measuring a temperature at a receiving opening of a bar of a stator of an electric drive machine for a motor vehicle

Abstract

The invention relates to a stator (10) for an electric drive machine (100) of a motor vehicle (K), comprising a stator main part (20), at least one winding assembly (30) which has a plurality of individual winding regions (32, 34) that are provided in respective slots of the stator main part (20), at least one bar (60) which is connected to at least one of the individual winding regions (32, 34), and at least one temperature sensor (90) which is at least indirectly and thermally conductively connected to the at least one bar (60). The at least one bar (60) has at least one receiving opening (70), into which the at least one temperature sensor (90) is at least partly introduced in order to measure the temperature of the bar (60). Other aspects of the invention relate to an electric drive machine (100) comprising at least one stator (10) and to a motor vehicle (K) comprising at least one electric drive machine (100).

Description

[0001] Temperature measurement at a receiving opening of a rail of a stator of an electric drive motor for a motor vehicle

[0002] The invention relates to a stator for an electric drive motor of a motor vehicle, comprising a stator base body, at least one winding arrangement having a plurality of individual winding regions arranged in respective slots of the stator base body, at least one rail connected to at least one of the individual winding regions, and at least one temperature sensor connected at least indirectly and in a thermally conductive manner to the at least one rail. Further aspects of the invention relate to an electric drive motor having a stator and to a motor vehicle. The winding arrangement can generally also be designed as an endless winding or endless wave winding and referred to as such. Alternatively, the winding arrangement can generally be designed as a hairpin winding and referred to as such.

[0003] In the stators of electric drive machines, it may be necessary to implement a temperature sensor for detecting the current temperature of current-carrying conductor sections on the stator. These conductor sections can, for example, be individual winding regions of endless wave windings. For this purpose, a stator for an electric machine, in particular for a drive machine designed as a drive machine for an electrically driven motor vehicle, is known from WO 2022 / 002295 A1, for example. The stator comprises a stator body with a plurality of stator windings and a temperature sensor for detecting the temperature of at least one section of a stator winding. The temperature sensor, together with a conductor section, is arranged in a trough-shaped receptacle of an add-on part and is fixed in the receptacle by means of a potting compound.The conductor section is designed in thermally conductive contact with the temperature sensor as a component of the stator winding or as a section thermally conductively connected to the stator winding.

[0004] The object of the present invention is to provide a stator, an electric drive motor, and a motor vehicle of the type mentioned above, which allow for improved maintenance. This object is achieved by a stator having the features of patent claim 1, by an electric drive motor having the features of patent claim 8, and by a motor vehicle having the features of patent claim 9. Advantageous embodiments with expedient further developments of the invention are specified in the subclaims.

[0005] A first aspect of the invention relates to a stator for an electric drive motor of a motor vehicle, comprising a stator base body, at least one winding arrangement having a plurality of individual winding regions arranged in respective slots of the stator base body, at least one rail connected to at least one of the individual winding regions, and at least one temperature sensor connected at least indirectly and in a thermally conductive manner to the at least one rail.

[0006] According to the invention, it is provided that the at least one rail has at least one receiving opening into which the at least one temperature sensor for measuring the temperature on the rail is inserted at least in part.

[0007] This is advantageous because inserting the temperature sensor into the receiving opening allows for a particularly simple arrangement of the temperature sensor for temperature measurement and, in particular, improved accessibility to the stator for any maintenance of the temperature sensor and / or its replacement. In other words, thanks to its arrangement on the rail, the temperature sensor can be replaced with particularly little effort and, for example, with little risk of a tool colliding with the winding arrangement. A further advantage is that by inserting the temperature sensor into the receiving opening, it enables at least a qualitative measurement of the temperature of a point that is particularly hot during operation of the electric drive machine, also known as a “hotspot,” or at least allows conclusions to be drawn about the course of this temperature or an average temperature value of a winding temperature of the individual winding areas.A further advantage is that the receiving opening represents an interface, i.e. a fastening point, also called a measuring interface, for the temperature sensor on the stator, which can be provided without major disruptions to the stator manufacturing process. The receiving opening, in particular an inner surface circumferentially bounding the receiving opening, represents an insulation-free, or in other words, stripped, zone of the rail. In principle, several types of connection that can be easily removed are conceivable, by means of which the temperature sensor, which is at least partially inserted into the receiving opening, can be held fixed to the rail. The temperature sensor can thus advantageously be inserted into the receiving opening with the formation of a positive connection and, additionally or alternatively, a frictional connection with the rail.The mounting opening forms a measuring interface, i.e., a connection point for securing the temperature sensor. This allows the temperature sensor to be securely held in an exposed location that is easily accessible for maintenance, allowing the temperature sensor to be easily replaced in the event of a fault. This prevents any damage to the insulation of the individual winding areas and thus the winding arrangement, not least during maintenance work, as well as any undesirable deformation of the individual winding areas beyond a process-safe level. The rail can also be referred to and / or designed as a busbar, a phase connection rail, or a star-point rail.

[0008] The invention is based on the finding that, in the case of stators of electric drive machines, it may be necessary to implement a temperature sensor for detecting the current temperature on the rail (phase connection rail or star point rail) or on the stator. It has proven particularly advantageous if the temperature sensor is mounted as close as possible to a so-called hotspot of the electric drive machine, but in any case in a partial area or component area that qualitatively has the temperature profile of the hotspot or an average value of a winding temperature occurring across the entire winding arrangement, in particular the endless wave winding or endless winding, or at least has a temperature profile proportional to the temperature profile of the hotspot or the average value.The arrangement of the temperature sensor proposed according to the present invention, for example in applications with endless wave winding, enables a corresponding temperature measurement at a location free of insulation material, so that no stripping and thus damage to the insulation of the individual winding areas, for example on the winding arrangement, is necessary for temperature determination.

[0009] In an advantageous development of the invention, the at least one receiving opening is spaced apart in the axial direction and / or in the radial direction of the stator from a winding head of the winding arrangement comprising the respective individual winding region bends of the individual winding regions. This makes the receiving opening particularly accessible for maintenance work on the temperature sensor, and the risk of a tool required for maintenance colliding with the winding head is particularly low.In a further advantageous development of the invention, the at least one receiving opening is spaced apart from an intermediate plane region in the axial direction of extension, wherein the intermediate plane region is delimited by two planes in the axial direction that are parallel to one another and oriented perpendicular to the axial direction of extension, and at least the majority of the individual winding region bends are arranged in the intermediate plane region, wherein a first plane of the two parallel planes is tangent to an end face of the stator base body facing the rail, and a second plane of the two parallel planes is tangent to the majority of the individual winding region bends or has a distance from the majority of the respective individual winding region bends that corresponds at most to an average winding diameter of a line element assigned to the winding arrangement.This is advantageous because it allows maintenance of the temperature sensor and, if necessary, its replacement to be carried out without any risk of a tool used for maintenance or replacement colliding with the bends of the individual winding areas. The winding diameter can be the total diameter of a conductor element forming the winding arrangement, i.e., the total diameter of the conductive core of the conductor element including the insulation surrounding this core.

[0010] In a further advantageous development of the invention, the at least one receiving opening is spaced from the stator base body in the radial direction of extension of the stator. This is advantageous because it provides improved accessibility to the receiving opening and thus also to the at least one temperature sensor for maintenance work. A central axis of the receiving opening can extend parallel to a rotational axis of a rotor of the electrical machine and parallel to a longitudinal axis of the rotor and of the stator. Alternatively, the central axis of the receiving opening can extend in the radial direction of extension and thus perpendicular to the rotational axis of the rotor of the electrical machine and perpendicular to the longitudinal axis of the rotor and of the stator of the electrical machine. Furthermore, the central axis of the receiving opening can extend diagonally and thus both in the axial direction and in the radial direction of extension of the stator.

[0011] In a further advantageous development of the invention, the at least one temperature sensor is reversibly detachably connected to the at least one rail. This advantageously enables non-destructive detachment of the temperature sensor from the rail (phase connection rail or star-point rail). Particularly residue-free detachment of the temperature sensor from the rail is advantageously possible if the temperature sensor is connected to the rail without a material bond. The term "material bond" means that there is no material bond, for example, in the form of an adhesive bond, between the rail and the temperature sensor.

[0012] In a further advantageous development of the invention, the at least one temperature sensor is pressed or inserted, at least partially, into the at least one receiving opening. This pressing process creates a particularly durable connection between the temperature sensor and the rail, while enabling good heat transfer between the rail and the temperature sensor. The insertion process allows for particularly low-effort detachability, allowing the temperature sensor to be easily removed from the receiving opening. Insertion requires less force than pressing.

[0013] In a further advantageous development of the invention, the at least one receiving opening is designed as a through-opening. This advantageously allows the temperature sensor, for example, a measuring tip of the temperature sensor, to be passed through the receiving opening, thereby creating a particularly large contact area between the rail and the temperature sensor. This large contact area enables a temperature measurement that is particularly representative of the winding arrangement.

[0014] A second aspect of the invention relates to an electric drive machine having at least one stator according to the first aspect of the invention. In this electric drive machine, both temperature measurement and maintenance of the temperature sensor can be performed in an improved manner.

[0015] A third aspect of the invention relates to a motor vehicle having at least one electric drive motor according to the second aspect of the invention. The electric drive motor of the motor vehicle can be subjected to improved temperature monitoring and maintenance.

[0016] The preferred embodiments and their advantages presented with respect to one of the aspects apply accordingly to the other aspects of the invention, and vice versa. The features and feature combinations mentioned above in the description, as well as the features and feature combinations mentioned below in the description of the figures and / or shown alone in the figures, can be used not only in the respective specified combination, but also in other combinations or on their own, without departing from the scope of the invention.

[0017] Further advantages, features and details of the invention emerge from the claims, the following description of preferred embodiments and from the drawings.

[0018] The invention is explained once again below using a specific embodiment. This shows:

[0019] Fig. 1 is a schematic perspective view of a portion of a stator having a stator base body and a winding arrangement with a plurality of individual winding regions arranged in respective slots of the stator base body, in which a rail is connected to at least one of the individual winding regions;

[0020] Fig. 2 is an abstract representation of a motor vehicle and an electric drive machine, which comprises the stator, which comprises a temperature sensor for temperature measurement, which is thermally conductively connected to the rail by the temperature sensor being partially inserted into a receiving opening of the rail.

[0021] Fig. 1 shows a section of a stator 10 of an electric drive machine 100 shown abstractly in Fig. 2. The electric drive machine 100 serves to drive a motor vehicle K, also shown abstractly in Fig. 2

[0022] The stator 10 has a stator base body 20 and a winding arrangement 30 with a plurality of individual winding regions 32, 34.

[0023] The individual winding regions 32, 34 are arranged in respective slots of the stator base body 20. Furthermore, the stator 10 has a rail 60 that extends at least partially in the circumferential direction U of the stator 10. The rail 60 can be designated and / or designed as a phase connection rail or a star point rail. In the present case, the rail 60 is integrally connected to the individual winding region 32 by a welded joint.

[0024] A temperature sensor 90 of the stator 10, shown schematically in Fig. 2, is directly thermally conductively connected to the rail 60. For this purpose, the rail 60 has a receiving opening 70, which is circumferentially delimited by an inner surface 72 of the rail 60. The temperature sensor 90 for measuring the temperature on the rail 60 is inserted into the receiving opening 70, which is designed as a through-opening. The temperature sensor 90 can also be passed through the receiving opening 70 in order to form a particularly durable positive and / or non-positive, yet reversible and thus non-destructively detachable connection between the temperature sensor 90 and the rail 60. In the present variant, the temperature sensor 90 is pressed into the receiving opening 70.

[0025] The receiving opening 70 can generally be spaced apart in the axial extension direction A and additionally or alternatively in the radial extension direction R of the stator 10 from a winding head 50 of the winding arrangement 30 comprising respective individual winding region bends 42, 44 of the individual winding regions 32, 34.

[0026] In addition, the receiving opening 70 is spaced apart from a plane intermediate region EZB in the axial direction of extension A, wherein the plane intermediate region EZB is delimited by two planes E1, E2 that are parallel to one another and oriented perpendicular to the axial direction of extension A in the axial direction of extension A, and at least the majority of the individual winding region bends 42, 44 are arranged in the plane intermediate region EZB. A first plane E1 of the two parallel planes E1, E2 is tangent to an end face 22 of the stator base body 20 facing the rail 60, whereas a second plane E2 of the two parallel planes E1, E2 is tangent to the majority of the individual winding region bends 42, 44 or is at a distance A1 from the majority of the respective individual winding region bends 42, 44. The distance A1 corresponds to a maximum of an average winding diameter D_W of a line element 31 assigned to the winding arrangement 30.

[0027] The receiving opening 70 can generally also be spaced apart from the stator base body 20 in the radial extension direction R of the stator 10, although this is not shown in Fig. 1 and Fig. 2. The present stator 10 provides a measuring tap on the rail 60 (phase or star point connection rail), which can be used on the stator 10, regardless of whether the winding arrangement 30 is designed as an endless wave winding or as a hairpin wave winding.

[0028] A significant advantage of the receiving opening 70 is that excessive stripping or damage to insulated areas of the winding arrangement 30 can be avoided, and any special components for implementing the temperature sensor 90 are not required. In particular, the use of complex manufacturing processes can be eliminated. The receiving opening 70 creates an interface for the temperature sensor 90, which in this case is plugged axially and thus in the axial extension direction A onto the winding arrangement 30 or the winding head 50, which can be designed in particular as a stator temperature sensor.

[0029] The individual winding region 32 is connected to the rail 60 in such a way that the intermediate plane region EZB lies between the rail 60 and the end face 22 in the axial direction of extension A. The individual winding regions 32, 34 and thus also the rail 60 are thus spaced further from the end face 22 in the axial direction of extension A than, for example, the individual winding region bends 42, 44. The advantage here is that no separate components need to be used and the receiving opening 70 provides a stripped area, which is a result of the stator manufacturing process that is necessary anyway.

[0030] The interface for the temperature sensor 90 can be created by doubling the rail 60, i.e., for example, by having a larger rail diameter than the winding diameter D_W. Additionally, the receiving opening 70 for receiving the temperature sensor 90—as shown in Fig. 1 and Fig. 2—can be provided as a hole in the rail 60 or, alternatively, by a U-shaped sheet metal part connected to the rail 60. When the receiving opening 70 is provided by such a sheet metal part, respective legs of the sheet metal part forming the U-shape can form the receiving opening 70.

[0031] The advantage over concepts known from the prior art is that the temperature sensor 90 is integrated into the rail 60 (phase connection rail or

[0032] Star point rail) and thus, if necessary, easy replacement of the temperature sensor 90 is ensured. Depending on requirements, the receiving opening 70 and thus the temperature sensor 90 can be arranged at any location where the individual winding areas 32, 34 are present, for example, in the form of standard pins (in a hairpin winding) or where the rail 60 runs.

[0033] The receptacle for the temperature sensor 90 provided by the receiving opening 70 enables an optimization of the temperature measurement with regard to a stator temperature of the stator 10 and can be implemented without great manufacturing effort.

[0034] List of reference symbols

[0035] 10 Stator

[0036] 20 stator base body

[0037] 22 front side

[0038] 30 Winding arrangement

[0039] 31 Line element

[0040] 32 single winding range

[0041] 34 single winding area

[0042] 42 Single winding area bending

[0043] 44 Single winding area bending

[0044] 50 winding head

[0045] 60 rail

[0046] 70 Recording opening

[0047] 72 interior surface

[0048] 90 Temperature sensor

[0049] 100 electric drive motors

[0050] A Axial extension direction

[0051] A1 distance

[0052] D_W winding diameter

[0053] ECB intermediate level area

[0054] E1 first level

[0055] E2 second level

[0056] R radial extension direction

[0057] K Motor vehicle

[0058] U circumferential direction

Claims

Claims 1. Stator (10) for an electric drive machine (100) of a motor vehicle (K), with a stator base body (20), with at least one winding arrangement (30) which has a plurality of individual winding regions (32, 34) which are arranged in respective slots of the stator base body (20), with at least one rail (60) which is connected to at least one of the individual winding regions (32, 34), and with at least one temperature sensor (90) which is connected at least indirectly and in a thermally conductive manner to the at least one rail (60), characterized in that the at least one rail (60) has at least one receiving opening (70) into which the at least one temperature sensor (90) for measuring the temperature on the rail (60) is inserted at least in part.

2. Stator (10) according to claim 1, characterized in that the at least one receiving opening (70) is spaced apart in the axial extension direction (A) and / or in the radial extension direction (R) of the stator (10) from a winding head (50) of the winding arrangement (30) comprising respective individual winding region bends (42, 44) of the individual winding regions (32, 34).

3. Stator (10) according to claim 2, characterized in that the at least one receiving opening (70) is spaced apart from a plane intermediate region (EZB) in the axial extension direction (A), wherein the plane intermediate region (EZB) is delimited by two planes (E1, E2) which are parallel to one another and oriented perpendicular to the axial extension direction (A) in the axial extension direction (A), and at least the majority of the individual winding region bends (42, 44) are arranged in the plane intermediate region (EZB), wherein a first plane (E1) of the two parallel planes (E1, E2) is tangent to an end face (22) of the stator base body (20) facing the rail (60) and a second plane (E2) of the two parallel planes (E1, E2) is tangent to the majority of the individual winding region bends (42, 44) or is at a distance (A1) from the majority of the respective single winding area bends (42, 44) which has a maximum of one average winding diameter (D_W) of a line element (31) assigned to the winding arrangement (30).

4. Stator (10) according to one of the preceding claims, characterized in that the at least one receiving opening (70) is spaced from the stator base body (20) in the radial extension direction (R) of the stator (10).

5. Stator (10) according to one of the preceding claims, characterized in that the at least one temperature sensor (90) is reversibly detachably connected to the at least one rail (60).

6. Stator (10) according to one of the preceding claims, characterized in that the at least one temperature sensor (90) is pressed at least partially into the at least one receiving opening (70).

7. Stator (10) according to one of the preceding claims, characterized in that the at least one receiving opening (70) is designed as a through opening.

8. Electric drive machine (100) with at least one stator (10) according to one of claims 1 to 7.

9. Motor vehicle (K) with at least one electric drive machine (100) according to claim 9.

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