ELECTRICAL MACHINE

Abstract

The invention relates to an electrical machine (10), comprising at least one first coil (12), which is surrounded by a first electrical insulation element (24) at least in a partial region, and at least one second coil (14), which is surrounded by a second electrical insulation element (26) at least in a partial region, wherein at least one electrically conductive layer (28) provided in addition to the coils (12, 14) and in addition to the electrical insulation elements (24, 26) is arranged between the coils (12, 14).

Claims

1. An electrical machine (10), comprising at least one first coil (12) which is sheathed at least in a subregion by a first electrical insulation (24), and comprising at least one second coil (14) which is sheathed at least in a subregion by a second electrical insulation (26), wherein at least one electrically conductive layer (28), which is provided in addition to the coils (12, 14) and in addition to the electrical insulations (24, 26), is arranged between the coils (12, 14).

2. The electrical machine (10) as claimed in claim 1, wherein the electrically conductive layer (28) is arranged within the first insulation (24) between said first insulation and the first coil (12).

3. The electrical machine (10) as claimed in claim 1, wherein the electrically conductive layer (28) is arranged outside the first insulation (24), as a result of which the first insulation (24) is arranged between the electrically conductive layer (28) and the first coil (12).

4. The electrical machine (10) as claimed in claim 2 or 3, wherein the electrically conductive layer (28) surrounds at least a portion of the first coil (12) on at least two sides which are averted from one another.

5. The electrical machine (10) as claimed in one of the preceding claims, wherein at least one second electrically conductive layer (30), which is provided in addition to the coils (12, 14) and in addition to the electrical insulations (24, 26), is arranged between the coils (12, 14).

6. The electrical machine (10) as claimed in claim 5, wherein the electrically conductive layers (28, 30) are electrically insulated from one another by a phase separator (40) which is arranged between said electrically conductive layers.

7. The electrical machine (10) as claimed in claim 5, wherein the second electrically conductive layer (30) is arranged within the second insulation (26) between said second insulation and the second coil (14).

8. The electrical machine (10) as claimed in claim 6 or 7, wherein the second electrically conductive layer (30) surrounds at least a portion of the second coil (14) on at least two sides which are averted from one another.

9. The electrical machine (10) as claimed in one of claims 5 to 8, wherein the second electrically conductive layer (30) is arranged outside the second insulation (26), as a result of which the second insulation (26) is arranged between the second electrically conductive layer (30) and the second coil (14).

10. The electrical machine (10) as claimed in one of claims 5 to 9, wherein the electrically conductive layers (28, 30) are electrically connected to one another with a high impedance.

11. The electrical machine (10) as claimed in one of the preceding claims, wherein the electrically conductive layer (28, 30) is electrically connected to a predetermined ground potential (34) with a high impedance.

12. The electrical machine (10) as claimed in one of the preceding claims, wherein a detection device (36) is provided, by means of which detection device an electrical voltage between the electrically conductive layer (28, 30) and a reference potential (34) can be detected.

13. The electrical machine (10) as claimed in claims 11 and 12, wherein the reference potential (34) is the ground potential (34).

14. An aircraft comprising at least one electrical machine (10) as claimed in one of the preceding claims.

Description

[0030] Further advantages, features and details of the invention can be gathered from the following description of preferred exemplary embodiments and with reference to the drawing. The features and combinations of features cited above in the description and the features and combinations of features cited below in the description of the figures and/or shown in the figures alone can be used not only in the respectively indicated combination but also in other combinations or on their own, without departing from the scope of the invention.

[0031] In the drawing:

[0032] FIG. 1 shows a detail of a schematic sectional view of an electrical machine according to a first embodiment; and

[0033] FIG. 2 shows a detail of a schematic sectional view of the electrical machine according to a second embodiment.

[0034] Identical or functionally identical elements are provided with the same reference symbols in the figures.

[0035] FIG. 1 shows a detail of a schematic sectional view of a first embodiment of an electrical machine 10 for a vehicle, in particular for an aircraft. In this case, the vehicle can be driven by means of the electrical machine 10. The electrical machine 10 has a stator, not shown in FIG. 1, and a rotor, not shown in FIG. 1, which can be driven by the stator and in this way can be rotated about a rotation axis relative to the stator. For example, at least one propeller of the aircraft can be driven by the rotor, so that the aircraft can be made to fly by means of the electrical machine 10. In other words, the aircraft can be driven in the air by means of the electrical machine 10. To this end, the electrical machine 10 is operated in a motor mode and therefore as an electric motor. In the motor mode, the rotor and, by means of said rotor, the propeller are driven by the stator and therefore rotated about the rotation axis relative to the stator. Use as a generator, that is to say an electrical machine which is driven by an internal combustion engine or turbine for example, is expressly likewise possible and also covered.

[0036] The electrical machine 10 has at least one first coil 12 and at least one second coil 14 which are wound, for example, onto a laminated core 16 of the electrical machine 10. In other words, the coils 12 and 14 are wound around respective subregions of the laminated core 16, so that the coils 12 and 14 are held on the laminated core 16. To this end, the laminated core 16 has respective teeth 18, wherein the teeth 18 are immediately or directly adjacent to one another in the circumferential direction, which runs around the rotation axis, of the electrical machine 10 and therefore of the stator or of the rotor. This means that no further tooth of the laminated core 16 is arranged between the teeth 18 in the circumferential direction of the electrical machine 10. A slot 20 of the laminated core 16 is arranged between the teeth 18 in the circumferential direction of the electrical machine 10, wherein the coils 12 and 14 are each arranged at least partially in the slot 20. Furthermore, the coil 12 is wound around a first one of the teeth 18, wherein the coil 14 is wound around a second of the teeth 18. Therefore, the coils 12 and 14 are also immediately or directly adjacent to one another, so that no other coil or winding of the electrical machine 10 is arranged between the adjacent coils 12 and 14 in the circumferential direction.

[0037] The respective coil 12 or 14 has at least one electrical conductor 22 which is formed, for example, from copper, and therefore the conductor 22 is designed, for example, as a copper conductor. The respective conductor 22 is wound around the tooth 18 in this case, so that in this way the respective coil 12 or 14 is formed at least by the respective conductor 22. The respective conductor 22 is, for example, a partial conductor and provided with a partial conductor insulation and in this way electrically insulated.

[0038] Furthermore, an electrical insulation, which is also referred to as a main insulation 24 or 26, is associated with the respective coil 12 or 14. This means that the main insulation 24 is associated with the coil 12 and the main insulation 26 is associated with the coil 14, so that the coil 12 is electrically insulated by means of the main insulation 24 and the coil 14 is electrically insulated by means of the main insulation 26. It can be seen in FIG. 1 that the respective main insulation 24 or 26 surrounds at least a length region of the respectively associated coil 12 or 14 completely circumferentially in its circumferential direction, so that at least the respective length region of the respective coil 12 or 14 is sheathed by the respective main insulation 24 or 26 completely circumferentially in the circumferential direction. In particular, the respective coil 12 or 14 is at least predominantly, in particular completely, sheathed by the respectively associated main insulation 24 or 26 and in this way electrically insulated, in particular toward the respectively other coil 14 or 12. The respective main insulation 24 or 26 is therefore also referred to as the first sheathing.

[0039] In order to now be able to ensure particularly safe operation of the electrical machine 10 and therefore of the aircraft overall, a first electrically conductive layer 28, which is provided in addition to the coils 12 and 14 and in addition to the main insulations 24 and 26, is associated with the coil 12 and therefore the main insulation 24, which first electrically conductive layer is arranged between the coils 12 and 14, in particular in the circumferential direction of the electrical machine 10. Furthermore, a second electrically conductive layer 30, which is provided in addition to the coils 12 and 14, in addition to the main insulations 24 and 26 and in addition to the electrically conductive layer 28, is associated with the coil 14 and therefore the main insulation 26, which second electrically conductive layer is likewise arranged between the coils 12 and 14. It can be seen in FIG. 1 that the respective electrically conductive layer 28 or 30 is designed as a second sheathing of the respective associated coil 12 or 14 in the first embodiment shown in FIG. 1. Therefore, the respective second sheathing surrounds at least a length region of the respective coil 12 or 14 completely circumferentially in its circumferential direction. In particular, the respective coil 12 or 14 is preferably at least partially, in particular at least predominantly or completely, sheathed by the respective second sheathing completely circumferentially in the circumferential direction. In the first embodiment, the respective second sheathing is arranged outside the respective main insulation 24 or 26, so that the main insulation 24 is arranged between the coil 12 and the second sheathing (electrically conductive layer 28). Accordingly, the second sheathing (electrically conductive layer 30) is also arranged outside the main insulation 26, so that the main insulation 26 is arranged between the coil 14 and the electrically conductive layer 30 (second sheathing). Furthermore, the electrically conductive layer 28 is arranged between the electrically conductive layer 30 and the coil 12, whereas the electrically conductive layer 30 is arranged between the electrically conductive layer 28 and the coil 14. The respective electrically conductive layer 28 or 30 is preferably formed by a solid component, that is to say by a component in the solid state of aggregation. The respective electrically conductive layer 28 or 30 can be formed in one piece, or else the respective electrically conductive layer 28 or 30 has a plurality of parts which are formed separately from one another and are connected to one another. It is further conceivable for the respective electrically conductive layer, respective electrically conductive layer 28 or 30 or the respective component which forms the respective electrically conductive layer 28 or 30 to be designed in a flexible or dimensionally unstable or else rigid or dimensionally stable manner.

[0040] Furthermore, provision is made in the case of the electrical machine 10 for the electrically conductive layers 28 and 30 to be electrically connected to one another with a high impedance. In other words, a high-impedance electrical connection 32 is provided, via which the electrically conductive layers 28 and 30 are electrically connected to one another. To this end, the high-impedance connection 32 has at least or precisely one electrical resistor R for each electrically conductive layer 28 or 30 for example. In addition, the electrically conductive layers 28 and 30 are electrically connected to a predetermined ground potential 34, so that the electrically conductive layers 28 and 30 are, for example, connected to ground. In other words, a preferably high-impedance ground connection of the electrically conductive layers 28 and 30 is provided, in particular in such a way that the electrically conductive layers 28 and 30 are electrically connected to the predetermined ground potential 34 with a high impedance and via the resistors R in particular.

[0041] In this case, the predetermined ground potential 34 is used as the reference potential in order to detect at least one electrical voltage between the electrically conductive layers 28 and 30 and the reference potential (predetermined ground potential 34) by means of a detection device 36, which is also referred to as a measuring device. In other words, the electrical machine 10 comprises the detection device 36, by means of which a voltage measurement can be carried out. As part of the voltage measurement operation, the abovementioned electrical voltage between the electrically conductive layers 28 and 30 and the predetermined ground potential 34 is detected, that is to say measured, by means of the detection device 36. If, for example, the detection device 36 detects that the electrical voltage which is detected by means of the detection device 36 exceeds a prespecifiable threshold value, a short circuit between one of the coils 12 and 14 and at least one of the electrically conductive layers 28 and 30 can be inferred in this way, so that damage to at least one of the main insulations 24 and 26 can be inferred as a result. Consequently, at least one protective measure or countermeasure can be carried out, as part of which, for example, the electrical machine 10 is switched off. Consequently, for example, total failure of a drive train, which comprises the electrical machine 10, for electrically driving the vehicle can be prevented.

[0042] The connection 32 further has a busbar 38 to which the electrically conductive layers 28 and 30 are electrically connected, in particular via the resistors R. Therefore, the electrically conductive layers 28 and 30 and possibly all further electrical layers (not illustrated) of identical construction are electrically connected to one another via the busbar 38. In addition, the electrically conductive layers 28 and 30 are electrically connected to the predetermined ground potential 34, which is common to the electrically conductive layers 28 and 30, via the busbar 38.

[0043] FIG. 2 shows a second embodiment of the electrical machine 10. Whereas in the first embodiment the respective electrically conductive layer 28 or 30 is designed as a sheathing of the respective coil 12 or 14, so that in the first embodiment the respective electrically conductive layer 28 or 30 is arranged on at least two sides of the respective coil 12 or 14 which differ from one another and in particular are averted from one another, the respective electrically conductive layer 28 or 30 is designed as a substantially two-dimensional layer in the second embodiment. This means that the respective electrically conductive layer 28 or 30 is arranged only on precisely one side of the respective coil 12 or 14, so that in the second embodiment in each case only precisely one side of the respective coil 12 or 14 is covered or overlapped by the respective electrically conductive layer 28 or 30 toward the respectively other coil 14 or 12.

[0044] In this case, at least one phase separator 40 is arranged between the electrically conductive layers 28 and 30 which are electrically insulated from one another by means of the phase separator 40.

[0045] A further difference between the first embodiment and the second embodiment is that the coils 12 and 14 which are arranged in the slot 20 follow one another in the circumferential direction and in this case directly in the first embodiment, so that no other coil is arranged between the coils 12 and 14. In the second embodiment, however, the coils 12 and 14 are arranged so as to follow one another or one behind the other in the radial direction of the electrical machine 10, wherein, for example, the coil 14 is at least partially, in particular at least predominantly or completely, covered or overlapped by the coil 12 in the radial direction of the electrical machine 10 toward the outside.

[0046] Machines which are arranged in a linear manner, for example linear motors, are not illustrated but are likewise covered by the invention.