Motor

Abstract

The invention relates to an electric machine (2) having a rotor (4) and a centrifugal pendulum (10), the rotor (4) having permanent magnets (8) and a number of pole pairs, the magnetic field of the permanent magnets being parallel to the rotor rotational axis (6) of the rotor (4), the centrifugal pendulum (10) having a natural frequency and a rotational point (12), the rotational point is fixed to the rotor (4) and has a distance from the rotor rotational axis (6) that is greater than zero, the natural frequency of the centrifugal pendulum (10) being coordinated with the number of pole pairs of the permanent magnets (8) of the rotor (4).

Description

Technical Field

[0001] The present invention relates to an electric motor and a vehicle. Background Art

[0002] A hybrid vehicle is known from EP 3 461 669 A1.

[0003] A hybrid module for a vehicle is known from DE 10 2014 222 644 A1.

[0004] DE 10 2009 012 485 A1 describes a drive train for a hybrid drive.

[0005] DE 10 2018 101 597 A1 describes a drive train for a vehicle. Summary of the Invention

[0006] Against this background, the object of the present invention is to optimize an electric machine.

[0007] This object is achieved by an electric machine and a vehicle having the features of the independent claims. Embodiments of the electric machine and the vehicle are derived from the dependent claims and the description.

[0008] The electric machine according to the present invention comprises a rotor and a centrifugal pendulum serving as a damper, such as a vibration absorber. The rotor has a rotor axis of rotation, permanent magnets, and a certain number of pole pairs, wherein the magnetic fields of the permanent magnets and / or the magnetic fields generated by the pole pairs are oriented largely parallel to the rotor axis of rotation, at least along the rotor axis of rotation. The centrifugal pendulum has a natural frequency and a rotation point fixed to the rotor. The rotation point is spaced at a distance greater than zero from the rotor axis of rotation, wherein a pendulum axis of the centrifugal pendulum extending through the rotation point is arranged parallel to and offset from the rotor axis of rotation. The natural frequency of the centrifugal pendulum is coordinated / matched and / or corresponds to the number of pole pairs of the permanent magnets of the rotor.

[0009] A centrifugal pendulum has a mass and a connecting element. The mass is fixed to a rotation point on the rotor via the connecting element and is rotatable relative to the rotor. The distance between the masses is adjusted by the length of the connecting element. The natural frequency of the centrifugal pendulum is not fixedly predetermined, but is coordinated with the number of pole pairs of the rotor.

[0010] A vehicle according to the present invention, such as a motor vehicle, includes at least one embodiment of the proposed electric machine. The electric machine is designed to drive at least one device, such as at least one device of the vehicle and / or the entire vehicle, typically for driving drive wheels as a vehicle device. As a hybrid vehicle, the vehicle can be driven or driven selectively by at least one proposed electric machine and another power unit, such as an internal combustion engine. It is also possible for the vehicle to be driven or driven solely by at least one proposed electric machine as a purely electric vehicle.

[0011] In one embodiment, the centrifugal pendulum has a natural frequency that is coordinated with a specific nth order of the rotor speed, i.e., the rotational non-uniformity and / or torque fluctuation of the rotor shaft. This means that the natural frequency of the centrifugal pendulum is adaptively equivalent to the number of pole pairs of the rotor and / or adaptively consistent with the number of pole pairs. Typically, the natural frequency of the rotor, or the natural frequency of the rotor rotating about the rotor axis of rotation during operation of the motor, has at least one order related to the number of pole pairs. Here, the natural frequency of the centrifugal pendulum is selected or can be selected to be equal to at least one order of the natural frequency of the rotor, typically in accordance with the speed, wherein at least one order of the natural frequency of the rotor can be canceled out by the centrifugal pendulum. The number of pole pairs, each consisting of a north pole and a south pole, typically also corresponds to the number of permanent magnets.

[0012] The electric motor has permanent magnets and / or permanent magnet magnetic fields aligned or oriented in line with or parallel to the rotor's axis of rotation. For an electric motor having a composite structure consisting of the rotor and the provided centrifugal pendulum, rotational vibrations of the rotating rotor during operation are reduced by the centrifugal pendulum adapted to the rotor.

[0013] In contrast, in known electric machines, the permanent magnets and / or magnetic fields are arranged at an angle relative to the rotor's axis of rotation and overlap with respect to the rotor's axis of rotation. A centrifugal pendulum, coordinated with the pole pair number, acting as a speed-adapted damper on and / or at the rotor of the electric machine, can reduce the cogging torque and / or torque ripple of the rotor. This eliminates the need for lossy torque regulation over a 360° rotation angle, for example, via a circuit for a speed-synchronous torque shaft, such as an inverter, because the rotation of the rotor is automatically adapted purely mechanically during operation by the centrifugal pendulum. This can improve the efficiency and performance of the electric machine and the vehicle to be driven by it. This can increase the range of the electrically driven vehicle and improve driver comfort.

[0014] In electric machines with one pole pair, the torque ripple occurs essentially at the first order of the rotor speed, with the natural frequency of the centrifugal pendulum adapted to the speed being coordinated to the first order. In the case of four pole pairs, the torque ripple occurs essentially at the fourth order of the rotor speed, with the natural frequency of the centrifugal pendulum adapted to the speed being coordinated to the fourth order.

[0015] In one embodiment, the electric motor includes a stator that surrounds a rotor and a centrifugal pendulum fixed to the rotor, wherein the rotor rotates within the stator during operation of the motor. The stator includes a plurality of electromagnets that surround the rotor. In this embodiment, the electromagnets and / or the magnetic fields generated by the electromagnets are also parallel to the rotor's axis of rotation. The electric motor can be operated both as a motor and as a generator.

[0016] It goes without saying that the features mentioned above and those yet to be explained below can be used not only in the respectively specified combination but also in other combinations or on their own without departing from the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The invention is schematically illustrated in the drawing according to one embodiment and is described schematically and in detail with reference to the drawing.

[0018] Figure 1 An electric machine known from the prior art is shown in a schematic diagram.

[0019] Figure 2a 、 Figure 2b An embodiment of an electric machine according to the invention is shown in a schematic diagram.

[0020] List of reference numerals:

[0021] 2 motors

[0022] 4 rotors

[0023] 6 Rotor rotation axis

[0024] 8 permanent magnets

[0025] 10 Centrifugal Pendulum

[0026] 12 rotation points

[0027] 14 connecting elements

[0028] 16 mass bodies

[0029] 18-pendulum rotation axis

[0030] 20 lines

[0031] 100 motors

[0032] 102 rotor

[0033] 104 Rotor rotation axis

[0034] 106 permanent magnet

[0035] Line 108 DETAILED DESCRIPTION

[0036] The accompanying drawings are described continuously and comprehensively. Like reference numerals denote like parts.

[0037] exist Figure 1 An electric machine 100 shown in FIG. 1 , known from the prior art, comprises a rotor 102 rotatable about a rotor axis of rotation 104 . The rotor 102 comprises a plurality of permanent magnets 106 , which are oriented obliquely relative to the rotor axis of rotation 104 , as indicated here by lines 108 .

[0038] exist Figure 2a In the side perspective view and Figure 2b The embodiment of the electric machine 2 according to the invention, each schematically shown in cross-section in FIG, comprises a rotor 4 having a central rotor axis of rotation 6 and a number of permanent magnets 8. The permanent magnets 8 and / or the magnetic fields generated by the permanent magnets are oriented or directed at least along the rotor axis of rotation 6, parallel to the rotor axis of rotation 6, which is Figure 2a This is indicated by line 20.

[0039] In one embodiment, the electric machine 2 additionally has a stator (not shown in greater detail here) comprising a plurality of electromagnets, which stator or these electromagnets surround the rotor 4. It is provided that the electromagnets and / or the magnetic fields generated by the electromagnets are aligned or oriented at least along the rotor axis of rotation 6, also parallel to the rotor axis of rotation 6.

[0040] The rotor 4 is also combined with a centrifugal pendulum 10, which serves as a mechanical damper, such as a vibration absorber, for the rotor 4. The centrifugal pendulum 10 has a rotation point 12, which is arranged on the permanent magnets 8 of the rotor 4. The rotation point 12 is located radially between the central rotor axis of rotation 6 and the outer wall of the permanent magnets 8. The centrifugal pendulum 10 also has an elongated connecting element 14, which is elongated in this case, and a mass 16. The mass 16 is rotatably fastened to the rotation point 12 via the connecting element 14.

[0041] During operation of the electric machine 2 , the rotor 4 rotates relative to the stator. The connecting element 14 and the mass 16 also rotate about a pivot axis 18 , which extends through the rotation point 12 and is aligned or oriented parallel to the rotor axis of rotation 6 .

[0042] The natural frequency of the centrifugal pendulum 10 is coordinated and / or corresponds to the number of pole pairs of the permanent magnets 8 of the rotor 4 .

Claims

1. An electric motor comprising a rotor (4) and a centrifugal pendulum (10), wherein: The rotor (4) has permanent magnets (8) and a certain number of pole pairs, wherein the magnetic field of the permanent magnets is parallel to the rotor rotation axis (6) of the rotor (4), wherein the centrifugal pendulum (10) has a natural frequency and a rotation point (12), which is fixed on the rotor (4) and has a distance greater than zero from the rotor rotation axis (6), wherein the natural frequency of the centrifugal pendulum (10) is coordinated with the number of pole pairs of the permanent magnets (8) of the rotor (4).

2. The motor according to claim 1, characterized in that The centrifugal pendulum (10) comprises a mass body (16) and a connecting element (14), wherein the mass body (16) is fixed to a rotation point (12) on the rotor (4) via the connecting element (14), wherein the distance is adjusted by the length of the connecting element (14).

3. The electric motor according to claim 1 or 2, which is used in a vehicle.

4. A vehicle having at least one electric machine (2) according to any one of the preceding claims.

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