US-12620861-B2 - Synchronous machine

US12620861B2US 12620861 B2US12620861 B2US 12620861B2US-12620861-B2

Abstract

An inductively electrically excited synchronous machine is disclosed. The synchronous machine includes a stator group with a housing and a stator arranged in the housing and a rotor group with a shaft and a rotor that is non-rotatably connected to the shaft. The rotor group is rotatably arranged about an axis of rotation in the stator of the stator group. A bearing shield and a bearing fixed in the bearing shield are provided. The bearing shield axially closes the housing of the stator group and the bearing rotatably receives the shaft of the rotor group. An energy transmitter with a hollow-cylindrical magnetic core is provided. The magnetic core is arranged radially between the bearing shield and the bearing and partially forms the bearing shield.

Inventors

Leonard Lorenz
Gustavo Esteves Albieri
Christoph Schmuelling

Assignees

MAHLE INTERNATIONAL GMBH

Dates

Publication Date: 20260505
Application Date: 20220824
Priority Date: 20210924

Claims (20)

1 . An inductively electrically excited synchronous machine, comprising: a stator group with a housing and a stator arranged in the housing, a rotor group with a shaft and a rotor that is non-rotatably connected to the shaft, the rotor group rotatably arranged about an axis of rotation in the stator of the stator group, a bearing shield and a bearing fixed in the bearing shield, the bearing shield axially closes the housing of the stator group and the bearing rotatably receives the shaft of the rotor group, an energy transmitter with a hollow-cylindrical magnetic core, and wherein the magnetic core is arranged radially between the bearing shield and the bearing and partially forms the bearing shield.
2 . The synchronous machine according to claim 1 , wherein the magnetic core is composed of a ferritic material.
3 . The synchronous machine according to claim 1 , wherein the energy transmitter comprises a reinforcing element, wherein the reinforcing element, located outside, encompasses and reinforces the magnetic core at least partially.
4 . The synchronous machine according to claim 3 , wherein the reinforcing element is composed of steel.
5 . The synchronous machine according to claim 3 , wherein: the reinforcing element comprises at least one hollow-cylindrical section, and the at least one hollow-cylindrical section lies against the magnetic core and is arranged to face the bearing or the bearing shield.
6 . The synchronous machine according to claim 3 , wherein: the reinforcing element is configured C-shaped and placed onto the magnetic core, and the reinforcing element encompasses the magnetic core on two sides encircling the axis of rotation and are coaxial relative to one another and an axial side oriented transversely to the axis of rotation.
7 . The synchronous machine according to claim 1 , wherein the bearing comprises an inner ring non-rotatably arranged on the shaft, an outer ring, and at least two rolling elements arranged between the outer ring and the inner ring.
8 . The synchronous machine according to claim 7 , wherein the outer ring of the bearing is in direct contact with the magnetic core or with a reinforcing element which, located outside, at least partially encompasses and reinforces the magnetic core.
9 . The synchronous machine according to claim 7 , wherein: the energy transmitter comprises a secondary coil encircling the axis of rotation and a disc carrying the secondary coil, the disc is oriented transversely to the axis of rotation and is non-rotatably connected to the shaft of the rotor group, and the secondary coil is arranged to be inductively interactable on a primary coil at least partially encompassed by the magnetic core.
10 . The synchronous machine according to claim 9 , wherein: the magnetic core axially projects over the bearing on one side, and the disc radially projects into the magnetic core in a region of the magnetic core axially projecting beyond the bearing.
11 . The synchronous machine according to claim 1 , wherein: the energy transmitter comprises a secondary coil encircling the axis of rotation and a disc carrying the secondary coil, the disc is oriented transversely to the axis of rotation and is non-rotatably connected to the shaft of the rotor group, and the secondary coil is arranged to be inductively interactable on a primary coil at least partially encompassed by the magnetic core.
12 . The synchronous machine according to claim 11 , wherein: the magnetic core axially projects over the bearing on one side, and the disc radially projects into the magnetic core in a region of the magnetic core axially projecting beyond the bearing.
13 . An inductively electrically excited synchronous machine, comprising: a stator group with a housing and a stator arranged in the housing, a rotor group with a shaft and a rotor that is non-rotatably connected to the shaft, the rotor group rotatably arranged about an axis of rotation in the stator of the stator group, a bearing shield and a bearing fixed in the bearing shield, the bearing shield axially closes the housing of the stator group and the bearing rotatably receives the shaft of the rotor group, an energy transmitter with a hollow-cylindrical magnetic core, and wherein the magnetic core is arranged radially between the bearing shield and the bearing, and wherein the magnetic core partially forms the bearing shield or is integrated in the bearing shield.
14 . The synchronous machine according to claim 13 , wherein the magnetic core is in direct contact with the bearing and the bearing shield.
15 . The synchronous machine according to claim 13 , wherein the energy transmitter comprises a reinforcing element that at least partially surrounds the magnetic core.
16 . The synchronous machine according to claim 15 , wherein the magnetic core is composed of a ferritic material, and the reinforcing element is composed of steel.
17 . The synchronous machine according to claim 15 , wherein: the reinforcing element comprises at least one hollow-cylindrical section, and the at least one hollow-cylindrical section lies against the magnetic core and is arranged to face the bearing and/or the bearing shield.
18 . The synchronous machine according to claim 15 , wherein: the reinforcing element has a C-shaped structure, and the C-shaped structure of the reinforcing element encompasses the magnetic core on two sides encircling the axis of rotation and are coaxial relative to one another and on an axial side oriented transversely to the axis of rotation.
19 . The synchronous machine according to claim 15 , wherein the bearing comprises an inner ring non-rotatably arranged on the shaft, an outer ring, and at least two rolling elements arranged between the outer ring and the inner ring.
20 . The synchronous machine according to claim 19 , wherein the outer ring is in direct contact with the reinforcing element.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to International Patent Application No. PCT/EP2022/073572 filed Aug. 24, 2022, which also claims priority to German Patent Application DE 10 2021 210 674.9 filed Sep. 24, 2021, the contents of each of which is hereby incorporated by reference in its entirety. TECHNICAL FIELD The invention relates to an inductively electrically excited synchronous machine. BACKGROUND An inductively electrically excited synchronous machine usually comprises a stator and a rotor rotatably arranged in the stator. There, the energy is transmitted to the windings in the rotating rotor by means of an energy transmitter. The energy transmitter comprises a stator-side primary coil and a rotor-side secondary coil, which electromagnetically interact with one another. Further, a stator-side inverter and a rotor-side rectifier are provided. The energy transmitter is arranged outside of a housing of the synchronous machine and disadvantageously requires additional installation space. SUMMARY The object of the invention therefore is to state, for a synchronous machine of the generic type, an improved or at least alternative embodiment, with which the described disadvantages are overcome. According to the invention, this object is achieved through the subject of the independent claim(s). Advantageous embodiments are subject of the dependent claims. An inductively electrically excited synchronous machine comprises a stator group with a housing and a stator arranged in the housing. In addition, the synchronous machine comprises a rotor group with a shaft and a rotor that is non-rotatably connected to the shaft. The rotor group is rotatably arranged about an axis of rotation in the stator of the stator group. Further, the synchronous machine comprises a bearing shield and a bearing fixed in the bearing shield, wherein the bearing shield axially closes the housing of the stator group and the bearing rotatably receives the shaft of the rotor group. In addition, the synchronous machine comprises an energy transmitter with a hollow cylindrical magnetic core. According to the invention, the magnetic core is arranged radially between the bearing shield and the bearing and partially reproduces the bearing shield. In connection with the present invention, the terms “axial” and “radial” always relate to the axis of rotation. The magnetic core is arranged between the bearing shield and the bearing and can be fastened to the bearing shield and/or to the bearing in a materially connected and/or non-positively connected and/or positively connected manner. The magnetic core can support the mechanical loads that occur in the synchronous machine. Through the arrangement of the magnetic core between the bearing shield and the bearing, the installation space required for the energy transmitter can be reduced and the synchronous machine can be configured more compact axially. In addition, costs of the synchronous machine can be reduced. Besides the magnetic core, the energy transmitter of the synchronous machine can also comprise further components. Accordingly, the energy transmitter can comprise a primary coil, a secondary coil, a rectifier and an inverter. The individual components of the energy transmitter are divided into primary-side or stator-side or stationary components and secondary-side or rotor-side or rotatable components. The magnetic core, the primary coil and the inverter are primary-side or stator-side or stationary components. The secondary coil and the rectifier are secondary-side or rotor-side or rotatable components. The primary coil and the secondary coil can electromagnetically interact with one another. The magnetic core can at least partially encompass or surround the primary coil and thus amplify the electromagnetic interaction between the primary coil and the secondary coil. The magnetic core can be advantageously formed from a ferritic material. In a further development of the synchronous machine the energy transmitter can comprise a reinforcing element. The reinforcing element, located outside, can include or surround the magnetic core at least partially. The reinforcing element can be firmly connected to the magnetic core in a materially connected and/or positively connected and/or non-positively connected manner. The reinforcing element can protect the magnetic core from mechanical loads and thus increase the lifespan of the magnetic core. The reinforcing element can be formed for example from steel. Advantageously, the reinforcing element can comprise at least one hollow-cylindrical section. The at least one hollow-cylindrical section of the reinforcing element can lie against the magnetic core and be arranged so as to face the bearing or the bearing shield. In addition it can be provided that the reinforcing element is configured C-shaped and is placed onto the magnetic core. Then, the reinforcing element can include the magnetic core on two sides encirclin