Rotor of an electrically excited synchronous machine

Abstract

The invention relates to a rotor of an electrically excited synchronous machine (1), comprising: a rotor shaft (8) which is rotatable about a rotor axis (7); a rotor body (9), in particular a rotor laminated core, which is coupled to the rotor shaft (8); and a secondary unit (10) of an energy transmitter system, in particular a rotary transmitter, which is connected to the rotor shaft (8) for conjoint rotation, for contactlessly transmitting electrical energy into an exciter coil (3) of the rotor (2) of the electric machine (1), wherein the secondary unit (10) comprises a secondary winding support (11), a secondary winding (12) arranged on the secondary winding support (11), and a circuit board (13) which extends in the radial direction with respect to the rotor axis (7) and which has a rectifier circuit (14) for generating a DC voltage for the exciter coil (3), characterized in that - the circuit board (13) of the secondary unit (10), in particular electronic or electrical components (15) of the circuit board (13), can be cooled with cooling fluid from the rotor shaft (8), and - the cooling fluid for cooling the circuit board (13) can be conducted in a radial direction onto a front side (13f) and / or a rear side (13b) of the circuit board (13).

Description

[0001] Description

[0002] title

[0003] Rotor of an electrically excited synchronous machine

[0004] State of the art

[0005] The invention is based on a rotor of an electrically excited synchronous machine according to the preamble of the main claim.

[0006] A rotor of an electrically excited synchronous machine is already known from DE2653401 A1, comprising a rotor shaft rotatable about a rotor axis, a rotor body coupled to the rotor shaft, in particular a rotor core, and a secondary unit of an energy transmission system, in particular a rotary transformer, which is rotationally fixedly connected to the rotor shaft for the contactless transmission of electrical energy to an excitation winding of the rotor of the electrical machine. The secondary unit comprises a secondary winding support, a secondary winding arranged on the secondary winding support, and a circuit board extending radially relative to the rotor axis, having a rectifier circuit for generating a DC voltage for the excitation winding. The rectifier circuit comprises diodes and rectifier mounting plates.A cooling fluid jet is sprayed onto the diodes and the rectifier mounting plates from a fixed cooling opening in a housing. The cooling is not optimal because the diodes are not continuously cooled by the cooling jet, but only at the times when the diodes move past and are hit by the cooling jet.

[0007] Advantages of the invention

[0008] The rotor of an electrically excited synchronous machine according to the invention with the characterizing features of the main claim has the advantage that the cooling of the rectifier circuit is improved by allowing the circuit board of the secondary unit, in particular electrical or electronic components of the circuit board, especially semiconductor elements, conductor tracks, or solder joints for interconnecting the components, to be cooled with the cooling fluid from the rotor shaft, and by allowing the cooling fluid for cooling the circuit board to be directed radially to a front and / or rear side of the circuit board. In this way, cooling fluid can be continuously directed from the rotor shaft to the cooling-relevant components of the rectifier circuit, in particular to the so-called hot spots of the rectifier circuit.

[0009] The measures listed in the subclaims enable advantageous further developments and improvements of the rotor of an electrically excited synchronous machine specified in the main claim.

[0010] According to an advantageous embodiment, the cooling fluid can be directed from a shaft cooling channel of the rotor shaft to the circuit board via at least one supply opening of at least one supply path. Sufficient cooling fluid for cooling the circuit board is provided via the at least one supply path.

[0011] It is particularly advantageous if the secondary winding support has a support passage for the rotor shaft to pass through, wherein an annular gap-shaped distribution channel is formed between a distributor section of the support passage and the rotor shaft. This distribution channel is provided as part of the supply path for distributing the cooling fluid to several supply openings arranged one behind the other in the circumferential direction and is fluidly connected to the shaft cooling channel via at least one shaft opening. This allows the cooling fluid to be directed to the circuit board via several supply openings, so that several cooling-relevant components of the rectifier circuit can be optimally cooled. Furthermore, this part of the supply path can be formed in a simple and cost-effective manner.

[0012] It is further advantageous if the respective supply opening of the supply path is provided radially within components of the circuit board, in particular radially within the circuit board. In this way, the cooling fluid can be guided from the supply opening in a radial direction along the circuit board and the cooling-relevant components of the circuit board.

[0013] It is very advantageous if, according to a first embodiment, the cooling fluid can be conducted from the respective feed opening as a cooling film or in a channel in the radial direction along the front and / or along the back of the circuit board. It is also advantageous if, according to the first embodiment, a boundary wall extending in the radial direction and circumferential direction is provided on the front of the circuit board and / or on the back of the circuit board to form a cooling channel that cools the circuit board, the cooling channel being formed between the circuit board and the boundary wall. In this way, a closed cooling channel for cooling the circuit board is formed. The circuit board can have vias in order to better cool the components of the circuit board.

[0014] Furthermore, it is advantageous if, according to a second embodiment, the cooling fluid can be directed from the respective supply opening as a spray or jet in the radial direction onto components of the circuit board. In this way, the components of the circuit board, in particular housing parts of the components or connection surfaces of the components to the circuit board, can be cooled directly.

[0015] It is also advantageous if the circuit board is arranged in a circuit board receptacle of the secondary winding support and / or is designed, in particular, in the shape of an annular disk. In this way, the circuit board receptacle of the secondary winding support can both hold or secure the circuit board and guide the cooling fluid in sections.

[0016] It is advantageous if the secondary unit has at least one outlet for centrifuging the cooling fluid, which is provided in particular on an inner circumference of a cylindrical section of the circuit board holder, especially in particular on a chamfer of the inner circumference, and / or on the front side of the circuit board. In this way, after cooling the circuit board, the cooling fluid can be centrifuged in a targeted manner toward a winding head of a stator of the electrical machine. As a result, the cooling fluid used to cool the secondary unit can also be used to cool the stator of the electrical machine.

[0017] It is also advantageous if the secondary unit has a flow connection upstream of the outlet and downstream of the supply opening, which is designed to direct cooling fluid from the rear side of the circuit board to the front side of the circuit board. In this way, the cooling fluid directed to the rear side can be directed from the rear side of the circuit board to the front side of the circuit board and from there, together with the cooling fluid from the front side, can be ejected via the outlet located on the front side.

[0018] The invention also relates to an electrical machine comprising a rotor according to the invention and also a static primary unit of the energy transmission system

[0019] drawing

[0020] An embodiment of the invention is shown in simplified form in the drawing and explained in more detail in the following description.

[0021] They show:

[0022] Fig.1 shows an electrical machine with an energy transmission system comprising a primary unit and a secondary unit according to the invention,

[0023] Fig.2 a view of the secondary unit according to Fig.1 and

[0024] Fig.3 a side view of the secondary unit according to Fig.1 and Fig.2.

[0025] Description of the embodiment

[0026] Fig.1 shows an electrical machine with an energy transmission system comprising a primary unit and a secondary unit according to the invention.

[0027] The electrical machine 1 is an electrically excited synchronous machine 1 which has a rotor 2 with an excitation winding 3 and a stator 4 with a stator winding 5.

[0028] The rotor 3 of the electric machine 1 comprises a rotor shaft 8 rotatable about a rotor axis 7, a rotor body 9 coupled to the rotor shaft 8, in particular a rotor core. Furthermore, a secondary unit 10 of an energy transmission system 6 is provided on the rotor 3, which is rotationally fixedly connected to the rotor shaft 8 and is used for the contactless transmission of electrical energy to the excitation winding 3 of the rotor 2 of the electric machine 1. The secondary unit 10 of the energy transmission system 6 interacts with a static primary unit 30 of the energy transmission system 6. The energy transmission system 6 is also referred to as a rotary transformer.

[0029] The secondary unit 10 comprises a secondary winding carrier 11, a secondary winding 12 arranged on the secondary winding carrier 11 and a circuit board 13 extending in the radial direction with respect to the rotor axis 7 with a rectifier circuit 14 for generating a DC voltage for the excitation winding 3.

[0030] According to the invention, the circuit board 13 of the secondary unit 10, in particular electronic or electrical components 15 of the circuit board 13, can be cooled with cooling fluid from the rotor shaft 8 and the cooling fluid for cooling the circuit board 13 can be directed in the radial direction onto a front side 13f and / or a rear side 13b of the circuit board 13.

[0031] The components 15 of the circuit board 13 can be, for example, semiconductor elements, conductor tracks, solder joints for connecting the components or so-called pinfins.

[0032] The cooling fluid can be guided from a shaft cooling channel 16 of the rotor shaft 8 via at least one supply opening 18 of at least one supply path 19 onto the circuit board 13.

[0033] Fig.2 shows a view of the secondary unit according to Fig.1 .

[0034] The secondary winding support 11 has a support passage 20 for the passage of the rotor shaft 8. Between a distributor section 21 of the support passage 20 and the rotor shaft 8, an annular gap-shaped distribution channel 22 is formed, which is provided as part of the supply path 19 for forwarding the flow of the cooling fluid to at least one supply opening 18 and is fluidly connected directly or indirectly to the shaft cooling channel 16 via at least one shaft opening 23. According to the exemplary embodiment, the distribution channel 22 is designed to distribute the cooling fluid to several supply openings 18 arranged one behind the other in the circumferential direction (Fig. 3). The respective supply opening 18 of the supply path 19 is arranged radially within the components 15 of the circuit board 13, in particular radially within the circuit board 13.

[0035] According to a first embodiment, the cooling fluid can be guided from the respective supply opening 18 as a cooling film or channeled in a radial direction along the front side 13f and / or along the rear side 13b of the circuit board 13. A boundary wall 25 extending in the radial direction and circumferential direction can be provided on the front side 13f of the circuit board 13 and / or on the rear side 13b of the circuit board 13 to form a cooling channel 26 that cools the circuit board 13. The cooling channel 26 is then formed between the circuit board 13 and the boundary wall 25.

[0036] Alternatively, according to a second embodiment, the cooling fluid can be directed from the respective supply opening 18 as a spray or jet in a radial direction onto the components 15 of the circuit board 13.

[0037] The circuit board 13 is arranged, for example, in a circuit board receptacle 27 of the secondary winding carrier 11.

[0038] The secondary unit 10 has at least one outlet 29 for centrifuging the cooling fluid, which is provided in particular on an inner circumference of a cylindrical section 27.1 of the circuit board holder 27, specifically in particular on a chamfer 28 of the inner circumference. The outlet 29 is formed, for example, on the front side 13f of the circuit board 13.

[0039] The secondary unit 10 can have a flow connection 31 upstream of the outlet 29 and downstream of the at least one supply opening 18, which is designed to conduct cooling fluid from the rear side 13b of the circuit board 13 to the front side 13f of the circuit board 13.

[0040] Fig.3 shows a side view of the secondary unit according to Fig.1 and Fig.2.

[0041] The circuit board 13 is designed, for example, in the shape of an annular disk and extends in the circumferential direction around the rotor axis 7 and in the radial direction between an inner circumference of the board and an outer circumference of the board.

Claims

Claims 1. Rotor of an electrically excited synchronous machine (1), with a rotor shaft (8) rotatable about a rotor axis (7), a rotor body (9), in particular a rotor core, coupled to the rotor shaft (8), and with a secondary unit (10) of an energy transmission system, in particular a rotary transformer, rotationally connected to the rotor shaft (8) for contactless transmission of electrical energy into an excitation winding (3) of the rotor (2) of the electrical machine (1), wherein the secondary unit (10) comprises a secondary winding support (11), a secondary winding (12) arranged on the secondary winding support (11), and a circuit board (13) extending in the radial direction with respect to the rotor axis (7) with a rectifier circuit (14) for generating a DC voltage for the excitation winding (3), characterized in that - the circuit board (13) of the secondary unit (10), in particular electronic or electrical components (15) of the circuit board (13), can be cooled with cooling fluid from the rotor shaft (8) and - the cooling fluid for cooling the circuit board (13) in the radial direction to a front side (13f) and / or a back side (13b) of the circuit board (13) is conductive.

2. Rotor according to claim 1, characterized in that the cooling fluid can be guided from a shaft cooling channel (16) of the rotor shaft (8) via at least one feed opening (18) of at least one feed path (19) onto the circuit board (13).

3. Rotor according to claim 2, characterized in that the secondary winding carrier (11) has a carrier passage (20) for the passage of the rotor shaft (8), wherein between a distributor section (21) of the carrier passage (20) and the rotor shaft (8) an annular gap-shaped distribution channel (22) is formed, which is provided as part of the feed path (19) for distributing the cooling fluid to a plurality of feed openings (18) arranged one behind the other in the circumferential direction and is fluidly connected to the shaft cooling channel (16) via at least one shaft opening (23).

4. Rotor according to one of claims 2 or 3, characterized in that the respective feed opening (18) of the feed path (19) is provided radially inside components (15) of the circuit board (13), in particular radially inside the circuit board (13).

5. Rotor according to one of claims 2 to 4, characterized in that the cooling fluid can be guided from the respective supply opening (18) as a cooling film or channel-guided in the radial direction along the front side (13f) and / or along the rear side (13b) of the circuit board (13).

6. Rotor according to claim 5, characterized in that on the front side (13f) of the circuit board (13) and / or on the back side (13b) of the circuit board (13) there is provided a boundary wall (25) extending in the radial direction and circumferential direction to form a cooling channel (26) cooling the circuit board (13), wherein the cooling channel (26) is formed between the circuit board (13) and the boundary wall (25).

7. Rotor according to claim 2 to 4, characterized in that the cooling fluid can be directed from the respective supply opening (18) as a spray or jet in the radial direction onto components (15) of the circuit board (13).

8. Rotor according to one of the preceding claims, characterized in that the circuit board (13) is arranged in a board receptacle (27) of the secondary winding carrier (11) and / or is designed in particular in the shape of an annular disk.

9. Rotor according to one of the preceding claims, characterized in that the secondary unit (10) has at least one outlet (29) for spinning off the cooling fluid, which is provided in particular on an inner circumference of a cylinder section (27.1) of the circuit board holder (27), especially in particular on a chamfer (28) of the inner circumference, and / or on the front side (13f) of the circuit board (13).

10. Rotor according to claim 9, characterized in that the secondary unit (10) upstream of the outlet (29) and downstream of the respective feed opening (18) has a flow connection (31) which is designed to supply cooling fluid from the back (13b) of the circuit board (13) to the front (13f) of the circuit board (13).

11. Electrical machine with a rotor (2) according to one of the preceding claims and with a static primary unit (30) of the energy transmission system (6).

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