Electric drive with stator winding and control device surrounded by shielding device

Abstract

An electric drive includes a rotor and a stator in toothed-coil technology, wherein the stator has a number of individual tooth modules. A respective individual tooth module has a stator winding which is wound around an associated tooth, a control device which is designed to generate an activation signal for the stator winding, and a shielding device which surrounds the stator winding and the control device.

Claims

1. An electric drive, comprising: a rotor; and a stator in toothed-coil technology, wherein the stator has a number of individual tooth modules, wherein each individual tooth module has: a stator winding which is wound around an associated tooth, a control device which is designed to generate an activation signal for the stator winding, and a shielding device which surrounds the stator winding and the control device.

2. The electric drive as claimed in claim 1, wherein a respective control device has an electric fuse element.

3. The electric drive as claimed in claim 1, wherein a respective control device has a power semiconductor module and/or an electric energy store.

4. The electric drive as claimed in claim 1, wherein a respective control device has a device for detecting the rotor position.

5. The electric drive as claimed in claim 1, wherein a respective control device has an energy supply connection.

6. The electric drive as claimed in claim 1, wherein the electric drive has a superordinate controller which has a data connection to the control devices of the respective individual tooth modules.

7. The electric drive as claimed claim 1, wherein the shielding device has a housing made of sheet steel, wherein the housing partially or completely surrounds the stator winding and the control device.

8. The electric drive as claimed in claim 1, wherein the shielding device is formed from potting compound containing soft magnetic particles, wherein the potting compound partially or completely surrounds the stator winding and the control device.

9. The electric drive as claimed in claim 1, wherein the rotor is provided with markings for coding the rotor position on its circumference.

10. The electric drive as claimed in claim 1, wherein the rotor is in the form of a permanent magnet rotor or a reluctance rotor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is described in detail below with reference to the drawings, in which:

(2) FIG. 1 schematically shows an individual tooth module according to the invention in accordance with a first embodiment,

(3) FIG. 2 schematically shows an individual tooth module according to the invention in accordance with a further embodiment,

(4) FIG. 3 schematically shows a topology of a logical connection of the individual tooth modules to a superordinate control unit according to a first embodiment,

(5) FIG. 4 schematically shows a topology of a logical connection of the individual tooth modules to a superordinate control unit according to a further embodiment, and

(6) FIG. 5 schematically shows a plurality of individual tooth modules which are connected in a parallel manner to a voltage intermediate circuit.

DETAILED DESCRIPTION OF THE DRAWINGS

(7) FIG. 1 shows, by way of example, a single individual tooth module 1 of a plurality of individual tooth modules which are part of an electric drive (not illustrated in any more detail). The electric drive also has a rotor (not illustrated) and a stator in toothed-coil technology and a rotor (not illustrated any further), wherein the individual tooth modules 1 are part of the stator.

(8) The rotor may be in the form of a permanent magnet rotor or a reluctance rotor, for example.

(9) A respective individual tooth module 1 has a stator winding 2 which is wound around an associated tooth 11 made of electrical steel sheet. In the present case, only winding heads of the stator winding 2 are schematically shown for reasons of the simpler illustration.

(10) The individual tooth module 1 has a control device 3 which is designed to generate an activation signal for the stator winding 2. For this purpose, the control device 3 has an electric fuse element 18, a power semiconductor module 5, an electric energy store 6, an optional device 7 for detecting the rotor position and an electronic module 16. The electronic module 16 may have, for example, a microcontroller or an FPGA and associated peripheral components such as resistors, capacitors, coils, A/D converters etc.

(11) The control device 3 has an energy supply connection 8 for connection to an energy supply or a DC intermediate circuit 17.

(12) A data transmission connection 12 is also provided, by means of which the control device 3 has a data connection to a superordinate controller 9.

(13) FIG. 3 shows, by way of example, a possible topology of a logical connection of the individual tooth modules 1 to the superordinate controller 9. One of the individual tooth modules 1 is defined as a master and regulates the electric drive and monitors communication. If the master individual tooth module fails, one of the previous slave individual tooth modules is defined as the new master individual tooth module and regulates the drive. If the superordinate controller 9 or the connection to the latter fails, the master starts an emergency program in which it regulates the modules to a predefined operating point.

(14) If the individual tooth modules 1 do not have a device 7 for detecting the rotor position, a central device 13 for detecting the rotor position may be alternatively provided, as shown in FIG. 4, which central device transmits the rotor position to the individual tooth modules via the respective data transmission connections 12, the device 13 also being able to be integrated in one of the individual tooth modules. If the rotor position detection fails, the drive can also continue to be operated in a regulated manner without a sensor. If the application allows, it is also possible to completely dispense with a system for detecting the rotor position.

(15) Furthermore, the controller 9 is additionally expanded in FIG. 4 with a superordinate regulation block 14 and a control block 15, the control block 15 also being able to be provided in the controller 9 from FIG. 3.

(16) The individual tooth module 1 in FIG. 1 has a shielding device 4 in the form of a sheet steel housing which surrounds the stator winding 2 and the control device 3 and shields them from the environment.

(17) FIG. 2 shows an embodiment of an individual tooth module 1′ without a device 7 for detecting the rotor position, in which the shielding device is formed from potting compound 10 containing soft magnetic particles, the potting compound 10 surrounding the stator winding 2 and the control device 3. The housing 4 of the embodiment from FIG. 1 may likewise be filled with potting compound.

(18) If an individual tooth module 1, 1′ fails, there is a reduction in the torque. The loss of torque is reduced by the structure comprising as many individual tooth modules 1, 1′ as possible. The necessary overdimensioning for compensating for a single fault is greatly reduced in comparison with 3-phase or 6-phase systems. As a result, the drive can have a smaller structure and this saves material, installation space and weight.

(19) If a winding 2 is destroyed by a winding short or external mechanical effects (for example penetration of a foreign body through the housing), this does not have any further effects other than the destruction of this one winding and the proportionate loss of torque.

(20) The fuse element 18 prevents a short circuit in the DC intermediate circuit as soon as a serious fault results in the failure of an individual tooth module 1, 1′. This results in increased operational reliability.

(21) On account of the structure according to the invention, the installation effort is reduced and fewer electrical connections are required, thus reducing the number of possible fault sources.

(22) The electric drive may be a synchronous machine, a synchronous reluctance machine or a BLDC machine, for example.

(23) The shielding device prevents electromagnetic influencing of the electronics and the influencing of the environment by the individual tooth module.

(24) The potting compound cannot catch fire and, as a result, also prevents the burning of the potted components. Defects as a result of mechanical effects, for example strong vibrations, can therefore be avoided. The drive is still functional even when liquid enters the housing.

(25) FIG. 5 shows, in a highly schematic manner, a plurality of individual tooth modules 1 which are connected in a parallel manner to a voltage intermediate circuit or DC intermediate circuit. The individual tooth modules 1 are uniformly distributed over a circumference of the stator. It goes without saying that, in addition to the components 2, 18, 5 and 6 shown, yet further components (not illustrated) may typically be present, for example current sensors, voltage sensors, temperature sensors, (load) resistors, coils, capacitors, etc.