Electric machine, in particular for a motor vehicle, and method for producing an electric machine of this type

Abstract

The invention relates to an electric machine having at least one winding (12) by means of which a magnetic field can be generated, and having a sensor device (22) by means of which the magnetic field can be detected, the sensor device (22) comprising at least one circuit board (24) having a plurality of circuit-board regions (26) which are at least partially mutually spaced in the circumferential direction (36) of the electric machine and between which respective length portions (L) of the winding (12) are located. The sensor device (22) comprises sensor elements (28) which are held on the circuit board (24) and by means of which the magnetic field can be detected, wherein at least two of the sensor elements (28) differ from one another in terms of their measuring principles for detecting the magnetic field.

Description

[0001] Electrical machine, in particular for a motor vehicle, and method for producing such an electrical machine

[0002] The invention relates to an electrical machine, in particular for a motor vehicle, according to the preamble of patent claim 1. Furthermore, the invention relates to a method for producing such an electrical machine according to the preamble of patent claim 9.

[0003] DE 102016 005232 A1 discloses a rotor position sensor for an electrical machine. DE 102013 225 141 A1 discloses a position sensor device for detecting the angular position of a rotor. DE 102013 020 985 A1 discloses an electrical machine for a motor vehicle. DE 102012 009 906 A1 discloses an electrical machine. DE 102008 042 912 A1 discloses a sensor device for detecting the rotational position of a rotating component. DE 102007 060241 A1 discloses an electrical machine with a sensor device for detecting the rotor position.

[0004] DE 10 2007 028482 A1 describes a sensor arrangement. DE 10 2005 004 322 A1 discloses a rotor position detection system using a Hall sensor and a flux guide element. Furthermore, DE 103 31 505 A1 discloses a sensor arrangement for determining the position angle of an electrical machine.

[0005] DE 102021 131 178 A1 discloses an electric machine in a housing with a stator and a rotor, which has one or more point field detectors for detecting stray flux within the housing. For this purpose, the point field detectors are arranged within the housing and can be located, among other things, on the rotor or the stator.

[0006] EP 2 214296 A1 describes a motor assembly in a motor housing with a motor housing opening into which a sensor housing can engage and be arranged. The sensor housing contains one or more Hall-effect sensors that protrude beyond the sensor housing and, when the sensor housing is inserted, are positioned in the intermediate regions of the teeth of the motor stator through slots in the motor housing opening.

[0007] The object of the present invention is to provide an electrical machine, in particular for a motor vehicle, and a method for producing such an electrical machine, so that a magnetic field of the electrical machine can be detected in a particularly advantageous manner.

[0008] This object is achieved by an electrical machine having the features of patent claim 1 and by a method having the features of patent claim 9. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims.

[0009] A first aspect of the invention relates to an electric machine, in particular for a motor vehicle. This means, for example, that the motor vehicle, also simply referred to as a vehicle and designed, for example, as a motor vehicle, in particular as a passenger car, in its fully manufactured state has the electric machine and can be driven, in particular purely electrically, by means of the electric machine. The electric machine has at least one winding, by means of which a magnetic field can be generated, in particular for driving a rotor of the electric machine. This means, for example, that the electric machine, in its fully manufactured state, has the aforementioned rotor, which can be driven by means of the magnetic field.For example, in its fully manufactured state, the electric machine has a stator and a rotor, wherein the rotor can be driven by means of the stator and thus rotated about a machine rotation axis of the electric machine relative to the stator. In particular, the rotor can be driven by means of the magnetic field and thus rotated about the machine rotation axis relative to the stator. In particular, it is conceivable that the winding mentioned is a winding of the stator and is therefore also referred to as a stator winding. For example, the electric machine can provide drive torques for driving the motor vehicle via its rotor. The electric machine has a sensor device by means of which the magnetic field can be detected.In particular, a variable that characterizes the magnetic field, i.e., describes or indicates it, such as a magnetic flux of the magnetic field, also referred to as magnetic flux, can be detected by means of the sensor device. For example, a leakage flux of the electrical machine, also referred to as magnetic leakage flux, can be realized by means of the sensor device, wherein the magnetic leakage flux describes a portion of the magnetic flux or is a portion of the magnetic flux. Thus, for example, a leakage flux measurement can be carried out by means of the sensor device, in which the leakage flux is measured, i.e., detected, by means of the sensor device. In other words, the sensor device can, for example, measure, i.e., detect, the magnetic flux and / or the leakage flux of the magnetic field and thus the magnetic field.Since the magnetic field can be used, for example, to drive the rotor, the magnetic field is also referred to as the rotor magnetic field. In particular, the magnetic field, in particular the magnetic flux and / or the leakage flux, can be measured using the sensor device, so that the detection or measurement of the magnetic field is also referred to as magnetic field measurement or rotor magnetic field measurement.

[0010] In order to be able to particularly advantageously detect, i.e., measure, the magnetic field and thus, for example, the magnetic flux and / or the stray flux, the invention provides that the sensor device comprises a printed circuit board (PCB), also referred to as a printed circuit board (PCB), which has a plurality of circuit board regions that are at least partially, in particular completely, spaced apart from one another in the circumferential direction of the electrical machine, between which respective longitudinal regions of the winding are arranged. The circumferential direction of the electrical machine, and thus of the stator and rotor, extends around the machine's axis of rotation.Since the circuit board regions are at least partially spaced apart from one another, respective through-openings are arranged between the circuit board regions in the circumferential direction of the electrical machine, which through-openings are continuous, in particular, in the axial direction of the electrical machine, the axial direction of which coincides with the machine's axis of rotation. The through-openings are penetrated by the longitudinal regions of the winding, in particular, in the axial direction of the electrical machine, the radial direction of which runs perpendicular to the axial direction of the electrical machine. In particular, the circuit board regions are arranged between the longitudinal regions of the winding in the circumferential direction of the electrical machine in such a way that, viewed in the circumferential direction of the electrical machine, the longitudinal regions and the circuit board regions are arranged alternately one after the other.Furthermore, the invention provides that the sensor device has sensor elements held on the circuit board, by means of which the magnetic field or the variable can be detected. Thus, for example, the magnetic flux and / or the leakage flux can be measured, i.e. detected, by means of the sensor elements. For example, the respective sensor element is or comprises at least or exactly one magnetic field sensor and / or magnetic flux sensor, by means of which the magnetic field, in particular the magnetic flux and / or the leakage flux, can be measured, i.e. detected. In particular, the number of sensor elements is at least ten. Preferably, the number of sensor elements is greater than ten, in particular greater than or equal to one hundred. It can be provided that at least or exactly one sensor element is provided per circuit board region.Furthermore, it is conceivable, for example, that the number of sensor elements is greater than the number of circuit board regions, wherein it is conceivable, for example, that, in particular, exactly one of the sensor elements is arranged on, in particular, exactly one of the circuit board regions, so that, for example, at least or exactly all of the circuit board regions or several of the circuit board regions are free of a sensor element. In other words, it is provided, for example, that none of the sensor elements is arranged on at least or exactly one of the circuit board regions or on several of the circuit board regions.

[0011] In order to realize a particularly weight-, space- and cost-effective design of the electrical machine and thus to be able to detect the magnetic field in a weight-, cost- and space-efficient manner, the invention provides that the circuit board regions are designed as teeth, which are also referred to as tabs or prongs. The teeth project inwards in the radial direction of the electrical machine, the radial direction of which runs perpendicular to the axial direction of the electrical machine, from a base region of the circuit board that is common to the teeth. The teeth are held on the base region and held together via the base region, in particular in such a way that the teeth and the base region are designed as one piece with one another, i.e. are formed from a single piece.This means in particular that the teeth and the base region are not composed of parts that are formed separately from one another and connected to one another, but rather the teeth and the base region are preferably formed from a single piece, thus designed as a monoblock or formed by a monoblock. In other words, it is preferably provided that the teeth and the base region are formed from an intelligent body that is manufactured in one piece, thus formed from a single piece and thus manufactured integrally. Each tooth ends inwards in the radial direction of the electrical machine at a free end of the respective tooth that is opposite, for example, the annular base region. The circuit board is thus comb-shaped, thus in the form of a comb, the teeth of which are the prongs.This allows for a cost-effective, space-saving and weight-efficient design of the circuit board and thus of the sensor device as a whole, while also enabling time-saving and cost-effective assembly of the circuit board.

[0012] In order to be able to measure, i.e. detect, the magnetic field and thus, for example, the magnetic flux and / or leakage flux particularly advantageously and precisely, it is further provided according to the invention that at least two of the sensor elements differ from one another in their measuring principles for detecting the magnetic field. Thus, for example, at least or exactly a first of the sensor elements belongs to a first sensor type, by means of which the magnetic field and thus, for example, the magnetic flux and / or the leakage flux can be or is detected according to or in accordance with a first measuring principle. Furthermore, for example, at least or exactly a second of the sensor elements belongs to a second sensor type different from the first sensor type, by means of which the magnetic field and thus, for example, the magnetic flux and / or leakage flux can be or is detected according to or in accordance with a second measuring principle different from the first measuring principle.The first and second measuring principles differ from each other, allowing the magnetic field to be detected with particular precision. Since, for example, the magnetic flux can be detected using the respective sensor element, the respective sensor element is or comprises, in particular, a so-called flux sensor, by means of which the magnetic flux can be detected.

[0013] The first sensor type or a respective sensor element belonging to the first sensor type is or comprises, for example, a 3D Hall sensor, by means of which the magnetic field, in particular the magnetic flux and / or stray flux, can be detected with particularly high resolution. The second sensor type or a respective sensor element belonging to the second sensor type is or comprises, for example, a Hall switch.

[0014] For example, with regard to detecting the magnetic field, in particular the magnetic flux and / or the leakage flux, the first sensor element has a very high measurement accuracy for measuring an amplitude of the magnetic field, in particular the magnetic flux, which allows, for example, a particularly precise or direct inference to be made about a temperature of the rotor, also referred to as the rotor temperature. In other words, the invention makes it possible to determine the rotor temperature particularly precisely because the at least two sensor elements differ from one another in their measurement principles for detecting the magnetic field, in particular the magnetic flux and / or the leakage flux, for example at least as a function of the magnetic field, in particular the magnetic flux and / or the leakage flux, detected by the first sensor element.For example, the first sensor element can have a measurement accuracy of, for example, 0.1% per Kelvin with regard to detecting the magnetic field, in particular the magnetic flux and / or the leakage flux, and with regard to determining the rotor temperature. In particular, the invention makes it possible, for example, to detect the amplitude of the magnetic field, in particular the magnetic flux and / or the leakage flux, particularly precisely by means of the first sensor element, so that, for example, the rotor temperature can be determined particularly precisely depending on the detected amplitude, in particular by inferring the rotor temperature, for example, directly depending on the detected amplitude.

[0015] The invention also enables a particularly cost-effective design of the electrical machine, as the electrical machine can be manufactured using only low material costs. Furthermore, cost-effective assembly is possible, as, for example, no specially designed rotating part is required and therefore does not have to be installed to detect, in particular, the magnetic field and thus, for example, the magnetic flux and / or the stray flux. Furthermore, a space- and weight-efficient design of the electrical machine can be realized, as the magnetic field can be detected, i.e., measured, using only a small number of parts.

[0016] In particular, it is conceivable that the sensor device has a plurality of circuit boards, namely the aforementioned circuit board and at least one or more further circuit boards, wherein the previous and following statements regarding the first circuit board can also be readily transferred to the respective further circuit board and vice versa.

[0017] This makes it possible, for example, to easily, redundantly, and precisely detect the magnetic field using the circuit boards and the respective sensor elements mounted thereon, in particular the magnetic flux and / or the leakage flux. By detecting or measuring the magnetic field or the magnetic flux, a failure of a current sensor, for example, can be detected early on. As a result, emergency operation of the electrical machine is feasible, which can be operated, in particular controlled or regulated, in emergency operation depending on the detected magnetic field, in particular depending on the magnetic flux and / or the leakage flux.It has been shown to be particularly advantageous if an arrangement, in particular a spatial arrangement, of the sensor elements and / or the sensor elements belonging to the first sensor type, the number of which is, for example, six, is dependent on a pole-slot ratio, whereby a particularly advantageous flux position signal, and thus a particularly advantageous detection of the magnetic field and thus, for example, of the magnetic flux and / or the stray flux, can be realized.

[0018] A further embodiment is characterized in that at least or exactly one of the sensor elements, in particular the first sensor element, i.e., the sensor element belonging to the first sensor type, is designed to detect both the magnetic field and at least or exactly one measured variable different from the magnetic field and provided in addition to the magnetic field. This ensures particularly advantageous operation of the electric machine in a particularly simple, space-saving, and weight-efficient manner.

[0019] To achieve particularly advantageous operation of the electrical machine, it has proven particularly advantageous if the measured variable is a temperature of the electrical machine. Thus, the at least one or exactly one sensor element is or comprises, for example, in particular exactly or at least, a magnetic field sensor, in particular a magnetic flux sensor simply referred to as a flux sensor, for detecting the magnetic field, in particular the magnetic flux and / or the stray flux, and the at least one or exactly one sensor element is or comprises, in particular exactly, a temperature sensor, by means of which the temperature can be detected, i.e., measured.The temperature is very preferably a temperature of the stator, also referred to as stator temperature, wherein, for example, the electrical machine can be operated, in particular controlled or regulated, particularly advantageously depending on the detected, i.e. measured, temperature.

[0020] In order to be able to realize particularly advantageous operation of the electrical machine in a particularly cost-effective manner, it is provided in a further embodiment of the invention that the other sensor elements of the sensor device provided in addition to the at least one or exactly one sensor element are designed to detect exclusively the magnetic field in relation to the measured variable and the magnetic field. This allows the other sensor elements to be designed to be lightweight, space-saving and cost-effective. Since the at least one or exactly one sensor element is designed both to detect the magnetic field and to detect the measured variable, the at least one or exactly one sensor element can, for example, carry out a main measurement in which the magnetic field and the measured variable are measured, i.e. detected, by means of the at least one or exactly one sensor element.The at least one or exactly one sensor element thus has a first function and a second function, also referred to as an additional function. The first function comprises measuring, i.e., detecting the magnetic field, and the second function comprises measuring, i.e., detecting the measurand.

[0021] In order to be able to detect, i.e. measure, the magnetic field, in particular the magnetic flux and / or the leakage flux, particularly precisely and thus advantageously, one embodiment of the invention provides that a respective one of the sensor elements is held, in particular precisely, on the respective circuit board area.

[0022] A further embodiment is characterized in that the base region is circular or circular-segment-shaped on its side facing away from the teeth, which faces outward in the radial direction of the electric machine. This allows for a particularly space-efficient design of the circuit board and thus of the sensor device as a whole on the outer circumference, allowing the circuit board and thus the sensor device to be installed particularly advantageously. This allows for particularly effective detection, i.e., measurement, of the magnetic field, in particular the magnetic flux and / or the stray flux.

[0023] In a further, particularly advantageous embodiment of the invention, the circuit board is inserted between the longitudinal sections in the radial direction of the electric machine, from the outside to the inside. This allows the circuit board and thus the sensor device to be assembled particularly quickly and cost-effectively, thereby enabling the electric machine to be manufactured particularly quickly and cost-effectively. Thus, the magnetic field, in particular the magnetic flux and / or the stray flux, can be detected, i.e., measured, in a particularly cost-effective manner.

[0024] In a further embodiment of the invention, the sensor elements are each at least partially embedded in the circuit board. This allows for a particularly space-efficient design of the sensor device, allowing the magnetic field, in particular the magnetic flux and / or the stray flux, to be detected particularly well.

[0025] In a further embodiment of the invention, the circuit board is manufactured by an injection molding process. In other words, the circuit board is preferably manufactured by injection molding. This allows a possibly complex circuit board geometry to be manufactured as needed in a particularly cost-effective manner, so that the circuit board can be advantageously positioned, particularly with respect to the winding. This allows the magnetic field to be measured, i.e., detected, particularly advantageously.

[0026] In order to be able to produce the circuit board particularly cost-effectively, a further embodiment of the invention provides that the circuit board is produced by laser direct structuring (LDS).

[0027] In a further, particularly advantageous embodiment of the invention, it is provided that the electrical machine has a laminated core carrying the winding, which is in particular formed separately from the winding.

[0028] It has proven particularly advantageous if a respective laminated core segment of the laminated core is connected to the circuit board on both sides in the circumferential direction of the electrical machine. This allows the circuit board to be integrated into the laminated core in a particularly space-efficient manner, particularly in the axial direction of the electrical machine, so that a particularly space-efficient design can be achieved, particularly when viewed in the axial direction of the electrical machine. In particular, the circuit board is designed in the precise shape of a laminated core segment, also referred to as a stator laminate, so that, for example, during production of the electrical machine, i.e. during a method for manufacturing the electrical machine, the circuit board can be placed directly on or onto the laminated core and, for example, can be glued directly to the laminated core. This can be achieved, for example, before and / or after the winding is introduced or arranged in or on the laminated core.As a result, the circuit board can be arranged with particularly precise fit between the laminated core and a winding overhang. This ensures very precise positioning of all sensor elements. In particular, excessive offset can be avoided, so that the magnetic field can be measured very precisely. For example, the circuit board is designed to fit a yoke of the stator, also referred to as the stator yoke, and / or an electrical pole of the electrical machine, so that a particularly advantageous integration of the circuit board and thus the sensor device into the electrical machine is possible. For example, the circuit board is arranged directly between the stator yoke and the winding overhang of the winding, particularly in the axial direction of the electrical machine, which allows a particularly advantageous arrangement of the circuit board and thus the sensor device.This means that the magnetic field can be detected, i.e. measured, particularly well.

[0029] For example, the stator yoke is the laminated core. The winding overhang is formed, for example, by the aforementioned longitudinal sections of the winding, such that the longitudinal sections and thus the winding overhang protrude from the stator or the laminated core in the axial direction of the electrical machine. In particular, it is provided that the longitudinal sections of the winding and thus the winding overhang protrude from an axial end face of the stator yoke or the laminated core in the axial direction of the electrical machine.

[0030] A further embodiment is characterized in that the respective sheet metal segment and the printed circuit board are arranged at least partially at the same height, viewed in the axial direction of the electric machine. This allows for a particularly space-efficient design, particularly viewed in the axial direction of the electric machine, and the printed circuit board and thus the sensor device can be integrated particularly advantageously into the electric machine, allowing the magnetic field to be detected particularly effectively.

[0031] Furthermore, it is preferably provided that the respective sheet metal segment and the circuit board are arranged flush with each other, particularly on a respective axial end face, which, for example, faces the winding head, thereby achieving a particularly space-efficient design. This allows the magnetic field to be detected particularly advantageously.

[0032] For example, the circuit board is at least partially, in particular at least predominantly and thus at least more than half or completely, overlapped by the laminated core in a first direction running parallel to the axial direction of the electrical machine or coinciding with the axial direction of the electrical machine. In this case, it is provided, for example, that the circuit board is arranged completely non-overlapping with the laminated core in a second direction running parallel to the axial direction of the electrical machine or coinciding with the axial direction of the electrical machine and opposite the first direction, and is therefore not overlapped by the laminated core. As a result, the magnetic field can be detected particularly advantageously by means of the sensor device, and the sensor device can be installed particularly easily and thus quickly and cost-effectively.

[0033] In order to be able to detect the magnetic field particularly precisely and thus particularly advantageously, it can be provided that the first sensor element and / or the second sensor element has a magnetic sensor designed to detect the magnetic field, which is an anisotropic magneto-resistive sensor, thus an AMR sensor.

[0034] Finally, it has proven particularly advantageous if the sensor device is designed to determine, i.e. to ascertain, at least one rotational position, also referred to as angular position or angular attitude, of the rotor of the electrical machine and / or an amplitude of the magnetic field and / or one or the aforementioned temperature of the electrical machine as a function of the detected magnetic field or as a function of the detected variable. Since the rotor is rotatable about the machine axis of rotation relative to the stator, the rotor can be rotated into a plurality of mutually different rotational positions or angular attitudes relative to the stator. In this case, at least or exactly one of the rotational positions or a plurality of rotational positions or angular attitudes can be detected by means of the sensor device as a function of the magnetic field.In particular, it is provided, for example, that the higher the number of sensor elements, the higher the accuracy, also referred to as angular accuracy, with which the at least one rotational position or positions can be determined. One background of the invention is, in particular, that the electrical machine, preferably designed as a rotating field machine, can be operated, in particular controlled, particularly advantageously as a function of the rotational position, also referred to as the rotor position. Typically, determining the rotor position with the aid of magnetic field sensors is very inaccurate, or a particularly large number of sensors is required, which must be individually mounted with precise positions, which can lead to a very cost-intensive manufacturing process.The invention now makes it possible to assemble the circuit board and thus the sensor device in a time-efficient, cost-effective and particularly precise manner, so that the magnetic field and, for example, subsequently at least one rotational position can be detected precisely and cost-effectively. The amplitude, also referred to as flux amplitude or rotor flux amplitude, can be used as very advantageous additional information, for example to determine, in particular ascertain, and very particularly calculate the temperature as a function of the amplitude, in particular from the amplitude, where the temperature is, for example, a temperature of the rotor, also referred to as the rotor temperature. Furthermore, particularly advantageous condition monitoring of the electrical machine can be implemented, for example as a function of the amplitude.The invention also makes it possible to detect demagnetization or partial demagnetization of the rotor as well as bearing damage and other damage at an early stage, so that particularly advantageous operation of the electrical machine can be achieved.

[0035] A second aspect of the invention relates to a method for manufacturing an electrical machine, in particular according to the first aspect of the invention. In the method according to the second aspect of the invention, the electrical machine is equipped with at least one winding, by means of which a magnetic field can be generated, and with at least one sensor device, by means of which the magnetic field can be detected.

[0036] In order to be able to detect the magnetic field, in particular a magnetic flux of the magnetic field and / or a stray flux of the magnetic field, in a particularly advantageous manner, the second aspect of the invention provides that the sensor device is produced from a circuit board having a plurality of circuit board regions that are at least partially, in particular completely, spaced apart from one another in the circumferential direction of the electrical machine, between which respective length regions of the winding are arranged. In addition, the sensor device is produced from sensor elements held on the circuit board, by means of which the magnetic field, in particular the magnetic flux and / or the stray flux, can be detected. It is further provided that at least or exactly two of the sensor elements differ from one another in their measuring principles for detecting the magnetic field.Advantageous and advantageous embodiments of the first aspect of the invention are to be regarded as advantages and advantageous embodiments of the second aspect of the invention and vice versa.

[0037] A third aspect is also disclosed, which relates to a method for operating an electrical machine according to the first aspect of the invention. Advantages and advantageous embodiments of the first aspect and the second aspect of the invention are to be regarded as advantages and advantageous embodiments of the third aspect, and vice versa.

[0038] Further advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and from the drawings. The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures, can be used not only in the respective specified combinations, but also in other combinations or on their own, without departing from the scope of the invention.

[0039] The drawing shows:

[0040] Fig. 1 is a schematic perspective view of a stator of an electrical machine, in particular for a motor vehicle;

[0041] Fig. 2 shows a partial schematic perspective view of a first embodiment of a circuit board of a sensor device of the electrical machine;

[0042] Fig. 3 is a schematic plan view of a second embodiment of the circuit board;

[0043] Fig. 4 is a schematic plan view of a third embodiment of the circuit board; and

[0044] Fig. 5 is a schematic representation of a sensor element held on the circuit board.

[0045] In the figures, identical or functionally identical elements are provided with the same reference symbols.

[0046] Fig. 1 shows a schematic perspective view of a stator 10 of an electrical machine, in particular of a motor vehicle. This means that the motor vehicle, also simply referred to as a vehicle and designed, for example, as a motor vehicle, in particular as a passenger car, in its fully manufactured state has the electrical machine and can be driven, in particular purely electrically, by means of the electrical machine. Preferably, the electrical machine is a high-voltage component whose electrical voltage, in particular electrical operating or rated voltage, is preferably greater than 50 volts, in particular greater than 60 volts, and very preferably amounts to several hundred volts.In its fully manufactured state, the electric machine comprises the stator 10 and a rotor (not shown in the figures), which is drivable by means of the stator 10 and is thus rotatable relative to the stator 10 about a machine rotation axis of the electric machine, the axial direction of which coincides with the machine rotation axis. In particular, the electric machine, whose radial direction runs perpendicular to the axial direction of the electric machine, can provide drive torques for driving the motor vehicle via its rotor.

[0047] The electrical machine, in particular the stator 10, has at least one winding 12, by means of which a magnetic field, in particular with a magnetic flux also simply referred to as flux or magnetic flux, can be generated. The winding 12 is very preferably designed according to hairpin technology, also referred to as hairpin technology, and is therefore also referred to as a hairpin winding. Since the winding 12 is a winding of the stator 10, the winding 12 is also referred to as a stator winding. The stator 10 and thus the electrical machine have a laminated core 14, to which the winding 12 is held. Thus, the winding 12 is supported by the laminated core 14. The axial direction of the electrical machine and thus of the stator 10 is illustrated in Fig. 1 by a double arrow 16. For example, the laminated core 14 is formed from a plurality of laminated core segments that are formed separately from one another and connected to one another, in particular pressed together.From Fig. 1 it can be seen that respective longitudinal regions L of the winding 12 on a first axial end face AS1 of the laminated core 14 protrude from the laminated core 14, in particular from the axial end face AS1 of the laminated core 14, in the axial direction of the electrical machine and thus of the laminated core 14, whereby the longitudinal regions L form at least one winding head 18 of the winding 12 arranged on the axial end face AS1. The laminated core 14 also has, for example, a second axial end face AS2 facing away from the first axial end face AS1 in the axial direction of the electrical machine and thus of the laminated core 14.In this case, it is conceivable, for example, that on the second axial end face AS2, second length regions L2 of the winding 12 protrude in the axial direction of the electrical machine and thus of the stator 10 of the laminated core 14 from the laminated core 14, in particular from the axial end face AS2 of the laminated core 14, whereby, for example, the length regions L2 on the second axial end face AS2 form a second winding head 20 of the winding 12.

[0048] The electric machine also has a sensor device 22, by means of which the magnetic field, in particular the magnetic flux and / or a stray flux of the electric machine, in particular the magnetic field, can be detected. In order to be able to particularly advantageously detect, i.e., measure, the magnetic field, in particular the magnetic flux and / or the stray flux, the sensor device 22 has at least one circuit board 24, which is preferably formed separately from the laminated core 14 and, for example, is connected at least indirectly, in particular directly, to the laminated core 14.

[0049] Fig. 2 shows a section in a schematic perspective view of a first embodiment of the sensor device 22 with a first embodiment of the circuit board 24. It is particularly clearly visible from Fig. 2 that the circuit board 24, which at least partially, in this case completely, has spaced-apart circuit board regions 26 in the circumferential direction of the electrical machine and thus of the stator 10 running around the machine rotation axis, between which the longitudinal regions L are arranged. Expressed conversely, the circuit board regions 26 are arranged between the longitudinal regions L in the circumferential direction of the electrical machine and thus of the stator 10.

[0050] The sensor device 22 also has sensor elements 28, which are held on the circuit board 24 and thus supported by the circuit board 24, in particular such that the sensor elements 28 are each at least partially embedded in the circuit board 24. Thus, the circuit board 24 is equipped with the sensor elements 28. The magnetic field, in particular the magnetic flux and / or the leakage flux, can be measured, i.e., detected, by means of the sensor elements 28. Thus, for example, in a method for operating the electrical machine, it is provided that the magnetic field, in particular the magnetic flux and / or the leakage flux, is detected, i.e., measured, by means of the sensor elements 28. For example, the sensor elements 28 and thus the sensor device 22 provide at least one, in particular electrical, signal that characterizes the magnetic field detected, i.e., measured, by means of the sensor elements 28.

[0051] From Fig. 2, it can be seen that a respective one of the sensor elements 28 is held, in particular precisely, on the respective circuit board region 26. Thus, for example, the sensor elements 28 are arranged between the length regions L. For example, in the first embodiment of the sensor device 22 shown in Fig. 2, one sensor element 28 is provided for each circuit board region 26, in particular precisely.

[0052] The circuit board regions 26 are designed as teeth or prongs which protrude inwards in the radial direction of the electrical machine and thus of the stator 10 from a base region 30 of the circuit board 24 that is common to the teeth and which end inwards in the radial direction of the electrical machine and thus of the stator 10 at a respective free end E of the respective tooth that is opposite the base region 30. The circuit board 24 is thus comb-shaped, in this case such that the circuit board 24 is designed in the form of a comb bent around the machine's axis of rotation. This makes it possible to assemble the circuit board 24 in a particularly time- and cost-effective manner such that, in a method for manufacturing the electrical machine, the circuit board 24 is inserted between the longitudinal regions L from the outside to the inside in the radial direction of the electrical machine and thus of the stator 10.The radial direction of the electric machine and thus of the stator 10 runs perpendicular to the axial direction of the electric machine and thus of the stator 10 and is illustrated in Figs. 1 and 2 by a double arrow 32. The axial direction of the electric machine and thus of the stator 10 is illustrated in Fig. 1 by a dash-dotted line 34, wherein the circumferential direction of the electric machine and thus of the stator 10 runs around the axial direction and is illustrated by a double arrow 36.

[0053] From Fig. 2 it can be seen that the base region 30 is designed in the shape of a circular segment on its side 35 facing away from the teeth (circuit board regions 26) and pointing outwards in the radial direction of the electric machine. From Fig. 1 it can be seen that in the circumferential direction of the electric machine and thus of the stator 10, a respective one of the lamination segments from which the laminated core 14 is formed adjoins the circuit board 24 on both sides, wherein a first of the lamination segments 38 adjoining the circuit board 24 in the circumferential direction and a second of the lamination segments adjoining the circuit board 24, in particular directly, in the circumferential direction is designated by 40.The respective lamination segment 38, 40 and the circuit board 24 are arranged at least partially, in particular at least completely, at the same height when viewed in the axial direction of the electrical machine, in this case such that the respective lamination segment 38, 40 and the circuit board 24 are arranged flush with one another on the axial end face AS1. In this case, the circuit board 24 is at least partially, in particular at least predominantly and thus at least more than half or completely, covered, i.e. overlapped, by the laminated core 14 in a first direction illustrated by an arrow 42, wherein the first direction illustrated by the arrow 42 runs parallel to the axial direction or coincides with the axial direction of the electrical machine.In a second direction, illustrated by an arrow 44 and opposite to the first direction, the printed circuit board 24 is arranged completely without overlap with the laminated core 14 and is therefore not overlapped by the laminated core 14, wherein the second direction runs parallel to the axial direction or coincides with the axial direction and is opposite to the first direction. Thus, the printed circuit board 24 is arranged in the axial direction of the electrical machine between the winding head 18 and at least one longitudinal region of the laminated core 14, whereby the magnetic field, in particular the magnetic flux and / or the stray flux, can be detected particularly advantageously. In particular, the sensor elements 28 are arranged in the axial direction between the winding head 18 and at least the longitudinal region of the laminated core 14.

[0054] In order to be able to detect the magnetic field, in particular the magnetic flux and / or the leakage flux, particularly precisely, it is further provided that at least or exactly one of the sensor elements 28, in this case a plurality of first sensor elements 28, is designed to measure, i.e. detect, the magnetic field, in particular the magnetic flux and / or the leakage flux, by means of a first measuring principle, that is to say according to or in accordance with the first measuring principle, wherein at least or exactly one second of the sensor elements 28, in this case a plurality of second sensor elements 28, is designed to measure, i.e. detect, the magnetic field, in particular the magnetic flux and / or the leakage flux, by means of a second measuring principle different from the first measuring principle, that is to say according to or in accordance with the second measuring principle.This means that the first sensor elements 28 and the second sensor elements 28 differ from one another in their measuring principles for detecting the magnetic field. For example, the respective first sensor element 28 is or comprises at least or exactly one first magnetic field sensor, which belongs to a first sensor type, and is therefore a sensor of a first sensor type. Furthermore, the respective second sensor element 28 is or comprises at least or exactly one second magnetic field sensor, which belongs to a second sensor type different from the first sensor type, and is therefore a sensor of a second sensor type different from the first sensor type. The respective first magnetic field sensor is designed to measure the magnetic field according to the first measuring principle, and the respective second magnetic field sensor is designed to measure the magnetic field according to the second measuring principle, and thus to detect it.

[0055] Furthermore, it is provided that at least or exactly one of the sensor elements is designed as a multi-function sensor. The multi-function sensor is, for example, one of the first sensor elements 28 or one of the second sensor elements 28. The multi-function sensor is designed to detect both the magnetic field and at least or exactly one measured variable that is different from the magnetic field and provided in addition to the magnetic field. In the exemplary embodiment shown in the figures, the additional measured variable is a temperature of the electrical machine, in particular of the stator 10, so that the temperature is also referred to as the stator temperature. In this case, the multi-function sensor comprises, for example, the magnetic field sensor belonging to the first sensor type or the second sensor type, and in addition, the multi-function sensor comprises at least or exactly one additional sensor, by means of which the additional measured variable can be detected or is detected.In the embodiment shown in the figures, the additional sensor is a temperature sensor, by means of which the aforementioned temperature can be or is detected. The multifunctional sensor is shown schematically in Fig. 5 and designated by 46.

[0056] It is preferably provided that the remaining sensor elements 28 of the sensor device 22, which are provided in addition to the at least one or exactly one multifunctional sensor 46, are designed to detect exclusively the magnetic field with respect to the measured variable and the magnetic field, so that, for example, the measured variable, i.e. the temperature, cannot be detected by means of the remaining sensor elements 28.

[0057] It has proven particularly advantageous if the sensor device 22 is designed to determine, i.e., ascertain, at least one rotational position, in particular a plurality of rotational positions, of the rotor, in particular with respect to the stator 10, and / or an amplitude of the magnetic field as a function of the detected magnetic field. The respective rotational position is also referred to as the rotor position and can be used, for example, to operate, in particular to control, the electrical machine as a function of the ascertained rotational position. The higher the number of sensor elements 28, the higher the accuracy with which the rotational position of the rotor can be ascertained. This ensures particularly precise control of the electrical machine.

[0058] Preferably, at least one of the lamination segments of the laminated core 14 and the circuit board 24 per se, i.e., considered on their own, are structurally identical, i.e., identically formed, particularly with regard to their respective outer contours, i.e., outer peripheral shapes. The number of sensor elements 28 is preferably in a range from 10 to 100 inclusive. Preferably, the number of first sensor elements 28 is equal to the number of second sensor elements. Very preferably, the circuit board 24 is manufactured by an injection molding process and / or by a laser direct structuring process, i.e., by laser direct structuring (LDS).Because the circuit board 24 is preferably designed in the form of a sheet metal segment of the laminated core 14, the circuit board 24 can be introduced into the manufactured winding 12, which is designed, for example, as a hairpin winding, in a time- and cost-effective manner, in particular in such a way that the comb-shaped circuit board 24 in the present case is inserted in the radial direction of the electrical machine and thus of the stator 10 from the outside to the inside between the length regions L of the winding 12.

[0059] By detecting the magnetic field, particularly the magnetic flux and / or the stray flux, bearing damage can be detected, for example, and a position signal can be recorded redundantly. Furthermore, changes in the electrical machine due to aging, temperature, or other damage can be compensated for. Compared to conventional solutions, moving parts or couplings are no longer required and can thus be avoided, allowing for particularly high levels of robustness.

[0060] Fig. 3 shows a schematic plan view of a second embodiment of the sensor device 22 with a second embodiment of the circuit board 24. It can be seen that a sensor element 28 is not arranged on each circuit board region 26, but rather the sensor elements 28 are provided on first of the circuit board regions 26, and second of the circuit board regions 26 are free of the sensor elements 28. This is implemented in such a way that a respective one of the sensor elements 28 is arranged on the respective first circuit board region 26, in particular precisely. For example, the first circuit board regions 26 and the second circuit board regions 26 are arranged alternately one after the other in the circumferential direction of the electrical machine running around the machine's axis of rotation.Alternatively or additionally, it can be provided that the first sensor elements and the second sensor elements are arranged alternately one after the other in the circumferential direction of the electric machine and the stator 10 running around the machine rotation axis.

[0061] From Fig. 3 it can also be seen that the sensor device 22 has a connection element 48, which is fastened, for example, to the circuit board 24. For example, the sensor device 22 can provide the aforementioned signal via the connection element 48. For example, a line can be connected, in particular electrically, to the connection element 48, so that the signal from the sensor device 22 can be transmitted to or onto the line, for example via the connection element 48. By means of the line, the signal can, for example, be guided to an electronic computing device, which can, for example, operate, in particular regulate or control, the electrical machine as a function of the signal.

[0062] In particular, by using the first sensor elements 28 and the second sensor elements 28, a particularly high level of measurement accuracy can be achieved, particularly with regard to measuring the magnetic flux and / or the rotational position. For example, the first sensor elements 28 and the second sensor elements 28 are or will be geometrically distributed across different teeth. In order for saturation harmonics in the signal to trigger each other, a six-phase system is suitable, for example. Thus, for example, six sensor elements 28 are each arranged electrically offset from one another by 30 degrees when viewed in the circumferential direction of the electrical machine. Advantageously, a mechanical, i.e. spatial, arrangement of the sensor elements 28 depends on the ratio of slots to poles of the electrical machine.If the electrical machine, in particular the stator 10, has, for example, 48 slots and eight poles, it is provided, for example, that the sensor elements 28 in.

[0063] are arranged offset from one another by 7.5 degrees in the circumferential direction of the electrical machine. Thus, for example, when viewed in the circumferential direction of the electrical machine, a distance between adjacent sensor elements 28 is 7.5 degrees, in particular when viewed in pairs. This is the case, for example, in a third embodiment of the sensor device 22 shown in Fig. 4 and in a third embodiment of the circuit board 24. In the second embodiment, it is conceivable that, viewed in the circumferential direction of the electrical machine, the sensor elements 28 are arranged in pairs offset from one another by 15 degrees, i.e., are spaced apart from one another, such that a mechanical offset of 15 degrees is provided between the sensor elements 28.It is conceivable to space the sensor elements 28 apart from one another by 15 degrees when viewed in the circumferential direction of the electrical machine, in particular when viewed in pairs, wherein, for example, the sensor elements 28 are offset from one another by 30 degrees when viewed electrically.

[0064] The magnetic field sensor of the multifunction sensor 46, designated 50 in Fig. 5, belongs to the first sensor type and is designed, for example, as a 3D Hall sensor. The temperature sensor of the multifunction sensor 46 is designated 52 in Fig. 5. The magnetic field sensor 50 and the temperature sensor 52 form a single unit.

[0065] 10 Stator

[0066] 12 windings

[0067] 14 sheet package

[0068] 16 Double arrow

[0069] 18 winding heads

[0070] 20 winding heads

[0071] 22 Sensor device

[0072] 24 boards

[0073] 26 Circuit board area

[0074] 28 Sensor element

[0075] 30 basic range

[0076] 32 double arrow

[0077] 34 dotted line

[0078] 35 page

[0079] 36 Double arrow

[0080] 38 sheet segment

[0081] 40 sheet segments

[0082] 42 Arrow

[0083] 44 Arrow

[0084] 46 Multifunction sensor

[0085] 48 connecting element

[0086] 50 magnetic field sensor

[0087] 52 Temperature sensor

[0088] AS1 axial end face

[0089] AS2 axial end face

[0090] L1 length ranges

[0091] L2 length ranges

Claims

Patent claims 1. An electrical machine having at least one winding (12) by means of which a magnetic field can be generated, and having a sensor device (22) by means of which the magnetic field can be detected, characterized in that the sensor device (22) comprises: - at least one circuit board (24) which has a plurality of circuit board regions (26) which are at least partially spaced apart from one another in the circumferential direction (36) of the electrical machine and between which respective length regions (L) of the winding (12) are arranged, wherein the circuit board regions (26) are designed as teeth which protrude inwardly in the radial direction (32) of the electrical machine from a base region (30) of the circuit board (24) which is common to the teeth and which end inwardly in the radial direction (32) of the electrical machine at a respective free end (E) of the respective tooth opposite the base region (30); and - sensor elements (28) held on the circuit board (24), by means of which the magnetic field can be detected, wherein at least two of the sensor elements (28) differ from one another in their measuring principles for detecting the magnetic field.

2. Electrical machine according to claim 1, characterized in that at least or exactly one of the sensor elements (28) is designed to detect both the magnetic field and at least or exactly one measured variable different from the magnetic field and provided in addition to the magnetic field.

3. Electrical machine according to claim 2, characterized in that the measured variable is a temperature of the electrical machine.

4. Electrical machine according to claim 2 or 3, characterized in that the remaining sensor elements (28) of the sensor device (22) provided in addition to the at least one or exactly one sensor element (46) are designed to detect exclusively the magnetic field with respect to the measured variable and the magnetic field.

5. Electrical machine according to one of the preceding claims, characterized in that the respective sensor element (28) is held on a respective one of the circuit board areas (26).

6. Electrical machine according to one of the preceding claims, characterized in that the base region (30) is circular or circular segment-shaped on its side (35) facing away from the teeth and pointing outwards in the radial direction (32) of the electrical machine.

7. Electrical machine according to one of the preceding claims, characterized in that the circuit board (24) is inserted in the radial direction (32) of the electrical machine from the outside to the inside between the longitudinal regions (L).

8. Motor vehicle with at least one electric machine according to one of the preceding claims.

9. A method for producing an electrical machine, in which the electrical machine is equipped with at least one winding (12) by means of which a magnetic field can be generated, and with at least one sensor device (22) by means of which the magnetic field can be detected, characterized in that the sensor device (22) is produced from: - a circuit board (24) having a plurality of circuit board regions (26) at least partially spaced apart from one another in the circumferential direction (36) of the electrical machine, between which respective length regions (L) of the winding (12) are arranged, wherein the circuit board regions (26) are designed as teeth which protrude inwardly in the radial direction (32) of the electrical machine from a base region (30) of the circuit board (24) common to the teeth and which end inwardly in the radial direction (32) of the electrical machine at a respective free end (E) of the respective tooth opposite the base region (30); and - sensor elements (28) held on the circuit board (24), by means of which the magnetic field can be detected, wherein at least two of the sensor elements (28) differ from one another in their measuring principles for detecting the magnetic field.

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