Rotor of an electrically excited synchronous machine

Abstract

Rotor of an electrically excited synchronous machine, which is rotatable about a rotor axis (2) and comprises a rotor body (3) which has a plurality of salient poles (4) arranged along a circumferential direction of the rotor (1), each of which comprises a pole shaft (5) and a pole shoe (6) as well as a pole center axis (7) running in the radial direction with respect to the rotor axis (2), wherein the pole shafts (5) are each enclosed by an individual coil (8) of an excitation winding (9) of the rotor (1), wherein pole slots (10) are formed between the salient poles (4), wherein the pole shafts (5) each have two pole flanks (15) which face the respectively adjacent pole slots (10), wherein the pole flanks (15) of at least one pole shaft (5) each have at least one inclined flank section (15s) which has a first helix angle (α 1) to the pole center axis (7), wherein the respective pole shoe (6) has support flanks (16), characterized in that the winding layers (18) of the respective individual coil (8) lie orthocyclically one above the other in such a way that on a coil side facing the support flanks (16) of the respective pole shoe (6) a coil layer (19) which is radially outermost with respect to the rotor axis (2) is formed, the wire cross sections of which lie with their center point on a straight line running parallel to the respective support flank (16) and which is free of wire gaps.

Description

State of the art

[0001] The invention is based on a rotor of an electrically excited synchronous machine according to the preamble of the main claim.

[0002] A rotor of an electrically excited synchronous machine is already known from DE102021211628 A1, which is rotatable about a rotor axis and comprises a rotor body, in particular a rotor core. The rotor body has a plurality of salient poles arranged along a circumferential direction of the rotor, each comprising a pole shaft, a pole shoe adjoining the pole shaft, and a pole center axis extending radially with respect to the rotor axis. The pole shafts are each enclosed by an individual coil of an excitation winding of the rotor. Pole slots are formed between the salient poles. The pole shafts each have two pole flanks facing the adjacent pole slots. The pole flanks of the pole shafts each have an inclined flank section that encloses a helix angle to the pole center axis. In this way, the respective individual coil is supported on the respective pole shaft against centrifugal forces.The pole shoes each have supporting flanks to support the respective individual coil. Advantages of the invention

[0003] 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 speed stability of the rotor is increased.

[0004] This is achieved according to the invention in that the winding layers of the respective individual coil are arranged orthocyclically one above the other in such a way that a coil layer which is radially outermost with respect to the rotor axis is formed on a coil side facing the support flanks of the respective pole piece, the wire cross sections of which lie with their center point on a straight line running parallel to the respective support flank and which is free of wire gaps.

[0005] According to the invention, a very positionally stable conductor arrangement is achieved in the respective individual coil, since the individual windings are given little or no space for a radially outward change in position due to centrifugal force.

[0006] 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.

[0007] It is very advantageous if the respective pole flank of the respective pole shaft has, viewed in the radial direction with respect to the rotor axis, several inclined flank sections arranged one behind the other, which are each offset from one another by a flank step and are offset radially outwards with each flank step closer to the respective pole center axis.

[0008] Each flank step of the respective pole flank reduces the shaft width of the respective pole shaft, measured in the circumferential direction, radially outward relative to the rotor axis. This inventive offset of the flank sections closer to the pole center axis creates additional winding space for additional winding layers, so that the conductor fill factor, in particular the copper fill factor, and thus the maximum torque and maximum power of the electrical machine can be increased. However, the shaft width of the respective pole shaft at the respective flank step should, if possible, not be less than the shaft width at the base of the respective pole shaft.

[0009] By mechanically supporting the individual coil on the pole flanks of the respective pole shaft, the speed stability of the salient pole or the rotor can be further increased.

[0010] The angled flank sections also create a barrier against centrifugal force-induced positional changes of the respective winding, which further increases the rotor's speed stability. This effect occurs because the windings of the individual coil, which are forced radially outward relative to the rotor axis by centrifugal forces, are also forced radially outward relative to the pole center axis due to the angled flank sections, which causes increased prestress in the electrical conductor and thus increased resistance to a change in position of the respective winding.

[0011] It is also advantageous if the angled flank sections of the same pole flank run parallel to each other. This further increases the conductor fill factor.

[0012] According to an advantageous embodiment, it is provided that the two pole flanks of the respective pole shaft are arranged mirror-symmetrically with respect to the pole center axis.

[0013] It is also advantageous if, in each inclined flank section of the respective pole flank, the shaft width continuously expands radially outward relative to the rotor axis. In this way, the inclined flank sections have a wedge shape, which mechanically supports the winding layers of the individual coil on the flank section and additionally creates the previously described self-locking effect against a centrifugal force-induced change in the position of the respective winding.

[0014] According to an advantageous embodiment, it is provided that the first helix angle of the inclined flank sections lies in an angular range between greater than zero degrees and twenty degrees.

[0015] It is also advantageous if the supporting flanks extend at a second helix angle to a perpendicular to the pole center axis, with the second helix angle being in an angle range between greater than zero degrees and twenty degrees, in particular between zero degrees and ten degrees. In this way, an orthocyclic winding pattern can be achieved. The enameled wires are wound without gaps, so that there is no possibility of a change in the conductor's position under very high loads.

[0016] It is advantageous if the individual coil is wound into a winding space between the supporting flanks of the pole shoe and the base flanks at the base of the respective pole shaft, forming winding layers, with the winding layers running parallel to the flank sections of the respective pole shaft. This achieves a high conductor fill factor.

[0017] According to an advantageous embodiment, the radially outermost winding layer of the respective individual coil with respect to the respective pole center axis can be stepped or linear. In this way, a high conductor fill factor can be achieved.

[0018] It is also advantageous if the winding start of each individual coil is located in a radially innermost winding position relative to the respective pole center axis, particularly at one of the flank steps of the respective pole shaft. This minimizes the mechanical stress on the winding start of each individual coil. Furthermore, the individual coil is easy to wind.

[0019] The invention further relates to an electrical machine with a rotor according to the invention. drawing

[0020] Embodiments of the invention are shown in simplified form in the drawing and explained in more detail in the following description.

[0021] They show: Fig. 1 shows a single salient pole of a rotor of an electrically excited synchronous machine according to a first embodiment of the invention and Fig. 2 shows a single salient pole of a rotor of an electrically excited synchronous machine according to a second embodiment. Description of the embodiments

[0022] Fig. 1 shows a single one of several salient poles according to the invention of a rotor of an electrically excited synchronous machine according to a first embodiment.

[0023] The rotor 1 of an electrically excited synchronous machine is rotatable about a rotor axis 2 and comprises a rotor body 3, in particular a rotor laminated core, which has a plurality of salient poles 4 arranged along a circumferential direction of the rotor 1. The salient poles 4 each have a pole shaft 5 and a pole shoe 6 adjoining the pole shaft 5, as well as a pole center axis 7 running in a radial direction with respect to the rotor axis 2. The pole shafts 5 of the salient poles 4 are each enclosed by an individual coil 8 of an excitation winding 9 of the rotor 1. Between the salient poles 4, pole slots 10 are formed for receiving the excitation winding 9. The pole shafts 5 of the salient poles 4 each have two pole flanks 15, which face the adjacent pole slots 10.

[0024] At least one inclined flank section 15s is formed on the pole flanks 15 of at least one pole shaft 5, which has a first helix angle α for centrifugal force support of the respective individual coil 8 on the respective pole shaft 5. 1 to the pole center axis 7.

[0025] The respective pole shoe 6 has supporting flanks 16 for supporting the respective individual coil 8.

[0026] According to the invention, the winding layers 18 of the respective individual coil 8 are arranged orthocyclically one above the other in such a way that, on a coil side of the individual coil 8 facing the support flanks 16 of the respective pole piece 6, a coil layer 19 is formed which is radially outermost with respect to the rotor axis 2, the wire cross-sections of which lie with their center on a straight line running parallel to the respective support flank and which is free of wire gaps, i.e., without a wire gap. A wire gap is understood to be a space suitable for completely accommodating a wire cross-section of the individual coil 8.

[0027] The respective pole flank 15 of the respective pole shaft 5 can, viewed in the radial direction with respect to the rotor axis 2, have several, in particular two or three, consecutively arranged pole flanks 15, which are arranged at the first helix angle α 1 have inclined flank sections 15s, each of which is offset from one another by a flank step 16.

[0028] The multiple flank sections 15s of the same pole flank 15 can be offset radially outward with each flank step 14 closer to the respective pole center axis 7. In this way, each flank step 14 of the respective pole flank 15 reduces a shaft width B of the respective pole shaft 5 measured in the circumferential direction with respect to the rotor axis 2. The inclined flank sections 15s of the same pole flank 15 each run parallel to one another, for example.

[0029] In each inclined flank section 15s of the respective pole flank 15, the shaft width B continuously widens radially outwards with respect to the rotor axis 2.

[0030] The first helix angle α 1 the inclined flank sections 15s, for example, lies in an angular range between greater than zero degrees and twenty degrees.

[0031] The two pole flanks 15 of the respective pole shaft 5 are, for example, mirror-symmetrical with respect to the pole center axis 7.

[0032] The support flanks 16 of the respective pole piece 6 run at a second helix angle α 2 to a perpendicular to the pole center axis 7, wherein the second helix angle α 2 in particular in an angular range between greater than zero degrees and twenty degrees, in particular between zero degrees and ten degrees.

[0033] The respective individual coil 8 is wound into a winding space 12 between the support flanks 16 of the respective pole shoe 6 and base flanks 17 formed at the foot of the respective pole shaft 5, forming superimposed winding layers 18. The winding layers 18 run parallel to the flank sections 15s of the respective pole shaft 5.

[0034] The radially outermost winding layer 18a of the respective individual coil 8 with respect to the respective pole center axis 7 can Fig. 1 stepwise or Fig. 2 be straight.

[0035] A winding start 20 of the respective individual coil 8 can be provided in a radially innermost winding layer 18i with respect to the respective pole center axis 7, in particular on one of the flank steps 14 of the respective pole shaft 5. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 102021211628 A1

[0002]

Claims

[1] A rotor of an electrically excited synchronous machine, which is rotatable about a rotor axis (2) and comprises a rotor body (3), in particular a rotor core, which has a plurality of salient poles (4) arranged along a circumferential direction of the rotor (1), each of which comprises a pole shaft (5) and a pole shoe (6) adjoining the pole shaft (5), as well as a pole center axis (7) extending in a radial direction with respect to the rotor axis (2), wherein the pole shafts (5) are each enclosed by an individual coil (8) of an excitation winding (9) of the rotor (1), wherein pole slots (10) are formed between the salient poles (4), wherein the pole shafts (5) each have two pole flanks (15) facing the respectively adjacent pole slots (10), wherein the pole flanks (15) of at least one pole shaft (5) each have at least one inclined flank section (15s),which has a first helix angle (α, 1 ) to the pole center axis (7), wherein the respective pole shoe (6) has supporting flanks (16) for supporting the respective individual coil (8), characterized by that the winding layers (18) of the respective individual coil (8) lie orthocyclically one above the other in such a way that a coil layer (19) which is radially outermost with respect to the rotor axis (2) is formed on a coil side facing the support flanks (16) of the respective pole piece (6), the wire cross-sections of which lie with their center point on a straight line running parallel to the respective support flank (16) and which is free of wire gaps. [2] Rotor according to claim 1, characterized bythat the respective pole flank (15) of the respective pole shaft (5) has, viewed in the radial direction with respect to the rotor axis (2), a plurality of inclined flank sections (15s) arranged one behind the other, which are each offset from one another by a flank step (14) and are offset radially outwards with each flank step (14) closer to the respective pole center axis (7). [3] Rotor according to claim 2, characterized by that each flank step (14) of the respective pole flank (15) reduces a shaft width (B) of the respective pole shaft (5) measured in the circumferential direction radially outwards with respect to the rotor axis (2). [4] Rotor according to one of claims 2 or 3, characterized by that the inclined flank sections (15s) of the same pole flank (15) run parallel to each other. [5] Rotor according to one of the preceding claims, characterized bythat the two pole flanks (15) of the respective pole shaft (5) are mirror-symmetrical with respect to the pole center axis (7). [6] Rotor according to one of the preceding claims, characterized by that in each inclined flank section (15s) of the respective pole flank (15) the shaft width (B) continuously widens radially outwards with respect to the rotor axis (2). [7] Rotor according to one of the preceding claims, characterized by that the first helix angle (α 1 ) of the inclined flank sections (15s) lies in an angular range between greater than zero degrees and twenty degrees. [8] Rotor according to one of the preceding claims, characterized by that the supporting flanks (16) are arranged at a second helix angle (α 2 ) to a perpendicular (27) to the pole center axis (7), wherein the second helix angle (α 2) in particular in an angular range between greater than zero degrees and twenty degrees, in particular between zero degrees and ten degrees. [9] Rotor according to one of the preceding claims, characterized by that the respective individual coil (8) is wound into a winding space (12) between the supporting flanks (16) of the pole shoe (6) and base flanks (17) provided at the foot of the respective pole shaft (5) to form winding layers (18), the winding layers (18) running parallel to the flank sections (15s) of the respective pole shaft (5). [10] Rotor according to one of the preceding claims, characterized by that the radially outermost winding layer (18a) of the respective individual coil (8) with respect to the respective pole center axis (7) is designed in a stepped or straight manner. [11] Rotor according to one of the preceding claims, characterized bythat a winding start (20) of the respective individual coil (8) is provided in a radially innermost winding position (18i) with respect to the respective pole center axis (7), in particular on one of the flank steps (14) of the respective pole shaft (5). [12] Electric machine with a rotor (1) according to one of the preceding claims.

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