STATOR WITH PINS FOR AN ELECTRIC MACHINE

Description

[0001] The invention relates to a stator with pins for an electric machine, in particular an electric motor. State of the art

[0002] Electric machines are widely known and, as electric motors, are increasingly used to power vehicles. An electric machine consists of a stator and a rotor.

[0003] The stator comprises numerous slots in which the windings are guided. The windings can be formed from insulated copper bars, known as pins. The rotor is located inside the stator and is connected to a rotor shaft.

[0004] Such a pin, UPin or hairpin motor is known, for example, from DE 11 2013 006 691 T5, DE 10 2010 053 719 A1, EP 3 096 441 A1, US 2011 / 0025162 A1, WO 2012 / 072754 A2 or US 9,136,738 B2. Task and solution

[0005] The object of the present invention is to provide a stator according to claim 1 with windings of pins which is easy to manufacture.

[0006] According to the invention, a stator for an electric machine comprises a plurality of pins arranged in slots in the stator on concentric circles at different distances from a stator center, each concentric circle forming a layer, wherein four pins in different layers are connected in series to form a turn, a first pin of the turn is located in a first slot in the 4n-3 layer, where n is a natural number, a second pin of the turn is located in a second slot in the 4n-2 layer, the second slot having a first radial distance in a first circumferential direction of the stator to the first slot, a third pin of the turn is located in the first slot in the 4n layer, a fourth pin of the turn is located in the second slot in the 4n-1 layer.

[0007] The layers can be numbered sequentially from the outside in towards the center of the stator. Natural numbers do not include zero.

[0008] A stator with the winding according to the invention is easy to manufacture and generates an efficient electromagnetic field with fewer iron and remagnetization losses, as well as better utilization of the lamination stack. The connection methods establish an electrically conductive connection between the pins in the slots. This connection method can involve welding conductors to the pins, or the pins can be designed as double pins, so-called upins, thus establishing a connection upon insertion into the stator. Welding the bent end sections of the pins together also constitutes a connection method.

[0009] According to the invention, the stator has a first and second end face and the first and second pins on the second end face are connected to each other by means of a first connection type, the second pin and third pins on the first end face are connected to each other by means of a second connection type, and the third pin and fourth pins on the second end face are connected to each other by means of a third connection type, wherein the first, second and third connection types differ from each other.

[0010] The different connection types enable improved manufacturing. Alternating the connection types on different end faces allows for the efficient formation of a winding around the stator teeth located between the slots. Even connection types on the same end face of the stator can differ due to different bending directions of a pin base towards the inside or outside of the stator.

[0011] A combination of the aforementioned connection types on different or the same end faces of the stator is also possible. Using the same connection type on the same end faces and different connection types on different end faces allows for simple and rapid manufacturing. For example, on one end face, the connection is made using a type of pre-bent pin, so-called double pins or upins, while on another end face of the stator, pins are welded individually or one side of each double pin is welded together. The weld points can be located at the bases of the pins or double pins.

[0012] Preferably, the pin at the beginning of a turn can be a first end pin, where the first end pin is designed as a single pin. A single pin is, for example, an IPin.

[0013] According to the invention, the stator has at least two turns and at least the fourth pin in the second slot is connected to a fifth pin in the 4n-3 layer in a third slot by means of a fourth connection type.

[0014] The rotating field generated with such a winding exhibits fewer disturbing harmonics and therefore has less torque ripple and smaller torque fluctuations, as well as better NVH behavior.

[0015] According to the invention, there is a second gap between the second groove and the third groove, which is larger than the first gap.

[0016] A stator with windings distributed across slots with different spacings exhibits lower ohmic AC losses and lower saturation.

[0017] According to the invention, the stator has a plurality of windings that extend over the entire circumference of the stator and thereby form a partial coil.

[0018] The windings therefore exhibit a symmetry that generates a uniform rotating field.

[0019] Preferably, each pin of two sub-coils can be connected to each other by means of a fifth or sixth connection type to form a coil. These pins can be so-called end pins, as they mark the end of a sub-coil.

[0020] In one embodiment of the invention, the end pins at the beginning or end of a coil can be designed as single pins.

[0021] Preferably, four pins of a coil can completely occupy four slots.

[0022] Preferably, the sub-coils can form six coils and be assigned three phases to them in such a way that two coils assigned to the same phase are located in three adjacent slots, with two different layers of the two outer slots being occupied by pins of other phases.

[0023] In a preferred embodiment of the invention, one input and one output of the at least two coils can be connected to each other, and the two coils can thereby be connected in parallel and, in particular, assigned to one phase.

[0024] Preferably, an input of at least two coils can be connected to each other by means of a seventh type of connection.

[0025] The seventh type of connection can be made by a conductor attached to the pins or by a conductive ring.

[0026] The two coils can be connected in parallel and can also be powered by the same phase. The parallel connection can be achieved by connecting the first and fifth or fourth and eighth end pins in pairs.

[0027] Furthermore, two phases can exhibit nearly identical current and voltage profiles, meaning that a six-phase inverter can only drive a three-phase motor. This arrangement allows for current sharing among the switching elements within the inverter.

[0028] Two coils in three adjacent slots can thus be connected in parallel and supplied by one phase, creating a stator with windings for a three-phase electric machine.

[0029] According to the invention, a vehicle has an electric machine with a stator according to one of the preferred embodiments. Character description

[0030] Figure 1 shows a stator. Figure 2 shows a stator with eight slots and four layers. Figure 3 shows a winding diagram of a first partial coil. Figure 4 shows a winding diagram of a second partial coil. Figure 5shows a stator with a first and second partial coil and their connection to each other, thus forming a first coil. Figure 6 shows a winding diagram of another partial coil. Figure 7 shows a winding diagram of another partial coil. Figure 8 shows a stator with two further partial coils and their connection to each other, thus forming a second coil. Figure 9 shows a stator with two coils, each consisting of two sub-coils. Figure 10 shows a stator with two additional coils. Figure 11 shows a stator with two additional coils. Figure 12 shows a stator with six coils. Figure 13 shows a winding diagram of a first and second coil. Figure 14 shows a vehicle with an electric machine, in particular an electric motor with a stator and an inverter.

[0031] Figure 1Figure 1 shows a stator 1 with a plurality of slots 5 in which pins 2 and 3 are guided. The stator 1 has a first end face 7 and an opposing second end face 9. On the first end face 7, inputs 81, 87, 101, 107, 111, 117 and outputs 83, 85, 103, 105, 113, 115 of partial coils for connecting the pins to a power source to operate the electric machine are shown. Naturally, a rotor is also required to operate an electric machine. The connection pins are located close together, allowing for short connecting leads.

[0032] Figure 2 Figure 1 shows a stator 1 with slots and pins on four layers, with only eight slots 51, 52, 53, 54, 55, 56, 57, 58 being shown. Pins 21 and 23 are arranged in slots 51, 52, 53, 54, 55, 56, 57, 58. Pins 21 and 23 are located next to each other in a slot. In the example of the Figure 2Four pins lie side by side in a slot. The four pins within a slot thus lie on different concentric circles L1, L2, L3, L4 around the center point M of the stator, which therefore form individual layers. There is a standard distance 11 between each pair of slots. This standard distance 11 is between all in Figure 2 The grooves shown are identical.

[0033] Figure 3 shows stator 1 from Figure 2 The pins are still arranged on concentric circles, i.e., layers, although the concentric circles are not shown for clarity. Figure 3 The diagram shows which pins are connected in series. Pin 21, which is also a first end pin and has an input 81, is located in a slot 51 in layer L4. This first end pin is, for example, a single pin configured as an IPin.

[0034] Pin 21 is connected to pin 27 in slot 92 via a third connection type 63, shown as a solid line. Pin 27 is located in layer L3. Pin 22 is connected to a first pin 25 in a first slot 53 via a fourth connection type 64, shown as a short dashed line. The first pin 25 is located in layer L1.

[0035] The first pin 25 is connected to a second pin 24 via a first connection type 61, shown as a dotted line. The second pin 24 lies in a second slot 94. Between the first slot 53 and the second slot 94 is a first gap 13, which is one slot smaller than the standard gap 11. Figure 2 The second pin 24 is located in layer L2.

[0036] The second pin 24 is connected to a third pin 23 in the first slot 53 via a second connection type 62, shown as a dashed line. The third pin 23 is located in layer L4. There is therefore space for two more pins between the first pin 25 and the third pin 23 in the first slot 53.

[0037] The third pin 23 is connected to a fourth pin 22 in the second slot 94 by means of a third connection type 63, shown as a solid line. The fourth pin 22 is located in layer L3. The second pin 24 and the fourth pin 22 are located in the middle of the slot, so that there is still space for two further pins on the stator inner layer L4 and the stator outer layer L1.

[0038] The connection of the first, second, third and fourth pins forms a first turn 41.

[0039] The fourth pin 22 is connected via the fourth connection type 64 to a fifth pin 26 in a third slot 55. Between the second slot 94 and the third slot 55 is a second gap 19, which is one slot shorter than the standard gap 11. The fifth pin 26 is located in layer L1. The previously described serial connection of the subsequent pins in the stator begins again with the fifth pin 26, with the fifth pin 26 being similar to the first pin 25, but with a 90-degree offset of the slot.

[0040] The serial connection of the fifth pin 26 with further pins in a further slot 96 forms a second turn 42. The first, second and third connection type 61, 62, 63 between these pins is identical to the respective first, second and third connection type 61, 62, 63 of the pins of the first turn 41.

[0041] The two turns 41, 42 are connected by the fourth connection type 64. By continuing the serial connection, the third turn 43 is formed in two further grooves 57 and 98. The turns 41, 42, 43 are each connected by the fourth connection type 64. The fourth connection type 64 between the respective turns is therefore identical. The first, second, and third connection types 61, 62, 63 between the pins of turn 43 are also identical to the first, second, and third connection types 61, 62, 63 of the first and second turns 41, 42.

[0042] The fourth turn 44 is also connected to the third turn 43 via the fourth connection type 64, however, this turn lacks a connection of the second connection type. Pin 28 represents a second end pin, and turn 44 is formed according to Figure 5 and is described there.

[0043] The four turns 41, 42, 43, 44 form a first partial coil by rotating clockwise around the stator 1. The first end pin 21 has an input 81 for connecting a power source. The partial coil terminates at the second end pin 28 of turn 44.

[0044] Figure 4 Figure 1 shows a stator 1, where eight slots 71, 73, 75, 77, 92, 94, 96, 98 are shown.

[0045] Pins 31, 32, 33, 34, 35, 38 are in the same way as pins 22, 23, 24, 25, 26, 28 of the Figure 3 connected. Even the type of connection is identical to Figure 3 and made clear by the same reference symbols. In the same way as with Figure 3 As described, the turns 45, 46, 47, 48 are formed and are connected to each other by the fourth type of connection 64.

[0046] The four turns 45, 46, 47, 48 form a second sub-coil by rotating counterclockwise around stator 1. This sub-coil begins with pin 31, which is a third end pin. The sub-coil ends with pin 38 of turn 48. The last pin 38 of turn 48 thus represents a fourth end pin. This fourth end pin 38 also has an output 83 for connecting a power source. Naturally, the input and output can be reversed.

[0047] Figure 5 shows a pin assignment through the first and second sub-coil from Figure 3 and 4, which are represented by black squares. Identical reference symbols denote identical pins, slots, and connections in the figures. The second end pin 28 of the fourth turn 44 of the first partial coil in slot 92, layer L2, and the third end pin 31 of the first turn 45 of the second partial coil in slot 71, layer L3, are connected by a fifth connection type 65. This connection forms the fourth turn 44, which is described in the Figure 3 As mentioned. The fifth connection type 65 bridges the second gap 19.

[0048] The two partial coils thus form a first coil 201 with an input 81 and an output 83 after two radial revolutions around the stator in opposite directions. A third gap 17 shown in the figure is one slot long.

[0049] The pins of coil 201 occupy all layers in four slots 92, 94, 96, 98. These four slots 92, 94, 96, 98 are each rotated by 90 degrees and have twice the standard spacing, or the sum of the first spacing 13 and the second spacing 19.

[0050] Figure 6Figure 1 shows a stator 1. The pins are arranged on concentric circles, i.e., layers, although the concentric circles are not shown for clarity. The figure 1 indicates which pins, represented as black squares on a white background, are connected in series to form a first partial coil of a second coil 202. A fifth end pin 21a is located in slot 91 in layer L4. This fifth end pin 21a is connected to a pin 27a in slot 72 via the third connection type 63, shown as a solid line. Pin 27a is located in layer L3. Pin 26a is connected to a first pin 25a in layer L1 in a first slot 93 via the fourth connection type 64, shown as a short dashed line.

[0051] The first pin 25a is connected to a second pin 24a via a first connection type 61, shown as a dotted line. The second pin 24a lies in a second slot 74. Between the first slot 93 and the second slot 74 is a first gap 13, which is one slot smaller than the standard gap 11. Figure 2 The second pin 24a is located in layer L2.

[0052] The second pin 24a is connected to a third pin 23a in the first slot 93 via a second connection type 62, shown as a dashed line. The third pin 23a is located in layer L4. There is therefore space for two more pins between the first pin 25a and the third pin 23a in the first slot 93.

[0053] The third pin 23a is connected to a fourth pin 22a in the second slot 74 by means of a third connection type 63, shown as a solid line. The fourth pin 22a is located in layer L3. The second pin 24a and the fourth pin 22a are located in the middle of the second slot 74, so that there is still space for two further pins on the stator inner layer L4 and the stator outer layer L1.

[0054] The connection of the first, second, third and fourth pins forms a first turn 41.

[0055] The fourth pin 22a is connected via the fourth connection type 64 to a fifth pin 26a in a third slot 95. Between the second slot 74 and the third slot 95 is a second gap 19, which is one slot longer than the standard gap 11. The fifth pin 26a is located in layer L1. The previously described serial connection of the subsequent pins in the stator begins again with the fifth pin 26a, whereby the fifth pin 26a, similar to the first pin 25a, has a slot offset of 90 degrees.

[0056] The serial connection of the fifth pin 26a with further pins in a further slot 76 forms a second turn 42. The first, second and third connection type 61, 62, 63 between these pins is identical to the respective first, second, third connection type 61, 62, 63 of the pins of the first turn 41.

[0057] The two turns 41, 42 are connected by the fourth connection type 64. By continuing the serial connection, the third turn 43 is formed in two further grooves 97 and 78. The turns 41, 42, 43 are each connected by the fourth connection type 64. The fourth connection type 64 between the respective turns is therefore identical. The first, second, and third connection types 61, 62, 63 between the pins of turn 43 are also identical to the first, second, and third connection types 61, 62, 63 of the first and second turns 41, 42.

[0058] The fourth turn 44 is also connected to the third turn 43 via the fourth connection type 64, however, this turn lacks a connection of the second connection type. Pin 28a represents a sixth end pin, and turn 44 is formed according to Figure 8 and is described there.

[0059] The four turns 41, 42, 43, 44 form a first partial coil by rotating clockwise around the stator 1. The fifth end pin 21a has an input 87 for connecting a power source. The partial coil terminates at the sixth end pin 28a of turn 44.

[0060] Figure 7 Figure 1 shows a stator 1, where eight slots 52, 54, 56, 58, 91, 93, 95, 97 are shown.

[0061] The pins are still arranged on concentric circles, i.e., layers, although the concentric circles are not shown for clarity. The diagram shows which pins, represented as black squares on a white background, are connected in series and form a second sub-coil of a second coil 202.

[0062] Pins 31a, 32a, 33a, 34a, 35a, 38a are in the same way as pins 22a, 23a, 24a, 25a, 26a, 28a of the Figure 6 connected. Even the type of connection is identical to Figure 6and made clear by the same reference symbols. In the same way as with Figure 6 As described, the turns 45, 46, 47, 48 are formed and are connected to each other by the fourth type of connection 64.

[0063] The four turns 45, 46, 47, 48 form a second sub-coil by rotating counterclockwise around stator 1. This sub-coil begins with pin 31a, which is the seventh end pin. The sub-coil ends with pin 38a of turn 48. The last pin 38a of turn 48 thus represents an eighth end pin. The eighth end pin 38a also has an output 85 for connecting a power source. Naturally, the input and output can also be reversed.

[0064] Figure 8 shows a pin assignment through the two sub-coils from Figure 6 and 7, which are represented by black squares on a white background. Identical reference symbols denote identical pins, grooves, and connections in the figures.

[0065] The sixth end pin 28a of the fourth turn 44 of the first partial coil in slot 72, layer L2, and the seventh end pin 31a of the first turn 45 of the second partial coil in slot 91, layer L3, are connected by a sixth connection type 66. This connection forms the fourth turn 44, which is described in the Figure 6 As mentioned, the sixth connection type, 66, bridges the first gap of 13.

[0066] The two partial coils thus form a second coil 202 with an input 87 and an output 85 after two radial revolutions around the stator in opposite directions. A third gap 17 shown in the figure is one slot long.

[0067] The pins of coil 202 occupy all layers in four slots 91, 93, 95, 97. These four slots are each rotated by 90 degrees and have twice the standard spacing, or the sum of the first spacing of 13 and the second spacing of 19.

[0068] Figure 9 shows a pin assignment through the first coil 201 from Figure 5 , which is represented by black squares. Identical reference symbols denote identical pins, slots, and connections in the figures. Furthermore, the second coil is from the Figure 8The coils are represented as black squares on a white background. The partial coils of the two coils are connected by the fifth connection type 65 (first coil) or the sixth connection type 66 (second coil). The fifth connection type 65 bridges the second gap 19. The sixth connection type 66 bridges the first gap 13. The pins of the two coils are located in three adjacent slots each. Between the outermost slots of each of the three adjacent slots is a third gap 15, which is two slots shorter than the standard gap 11.

[0069] Thus, two parallel coils are shown, each consisting of two sub-coils. The inputs and outputs of the coils are also shown. The input 81 of the first coil is located at slot 51 and the output 83 at slot 92. The input 87 of the second coil is located at slot 91 and the output 85 at slot 52. The inputs and outputs of both coils are therefore located in adjacent slots.

[0070] Figure 10 The pin assignment is shown by a third and fourth coil in the black squares with a white dot and the white squares with a black dot. This is created by a combination of the Figure 3 , 4 , 5 , 6 , 7 , 8 known winding scheme, which is offset by eight slots counterclockwise compared to the pins and connections of the sub-coils shown there.

[0071] The inputs 101 and outputs 103 of the third coil and the inputs 107 and outputs 105 of the fourth coil are also shown. The inputs and outputs of both coils are thus located in adjacent slots.

[0072] Figure 11 The pin assignment is shown by a fifth and sixth coil in the black squares with a white cross and the white squares with a black cross. This is created by a combination of the Figure 3 , 4 , 5 , 6 , 7 , 8A known winding diagram is shown, offset by four slots counterclockwise compared to the pins and connections of the sub-coils shown there. The inputs 111 and outputs 113 of the fifth coil and the inputs 117 and outputs 115 of the sixth coil are also shown. The inputs and outputs of both coils are thus located in the same slot.

[0073] Figure 12 shows a pin assignment through the six coils as a combination of the Figure 9 , 10 and 11 The position of inputs 81, 87, 101, 107, 111, 117 and outputs 83, 85, 103, 105, 113, 115 shows that the coils can be connected within 16 slots. In the example stator with forty-eight slots, the inputs and outputs can thus be connected within one-third of the stator's circumference. Purely in terms of the inputs or outputs, separate connections within ten slots would be possible.

[0074] Figure 13 The winding diagram shows the two partial coils of the first coil 201 and second coil 202. The consecutive "slot number" is not a reference mark. The reference marks with arrows at the slots are identical to those in the previous figures and allow for comparison with them.

[0075] Figure 14 Figure 403 is a schematic diagram of an embodiment of a vehicle 403, for example a hybrid vehicle or an electric vehicle, comprising an electric machine 401, in particular an electric motor, with an embodiment of the stator 1 for driving the vehicle 403. Furthermore, the vehicle 403 can have an inverter 405 which supplies the electric machine 401 with an alternating current from a direct current source. List of reference symbols

[0076] 1 Stator 2, 3 Pin 7 First end face 9 Second end face 11 Standard spacing 13 First spacing 17 Third spacing 19 Second spacing 21 First end pin 28 Second end pin 31 Third end pin 38 Fourth end pin 21a Fifth end pin 28a Sixth end pin 31a Seventh end pin 38a Eighth end pin 22 - 27, 22a - 27a Pins 32 - 37, 32a - 37a Pins 41 - 48 Turn 51 - 58 Slots 61 First connection type 62 Second connection type 63 Third connection type 64 Fourth connection type 65 Fifth connection type 66 Sixth connection type 71 - 78 Slots 81, 87, 101, 107, 111, 117 Input 83, 85, 103, 105, 113, 115 Output 91 - 98 Slots 201 First coil 202 Second coil 401 Electric machine 403 Vehicle 405 Inverter L1, L2, L3, L4 Layer M Stator center

Claims

1. Stator (1) for an electric machine (100), comprising a first end face (7), an opposite second end face (9) and a multiplicity of pins (22, 23, 24, 25), which are arranged in concentric circles with different distances from a stator centre point (M) in slots (51-58, 71-78, 91-98) in the stator (1), and each concentric circle forms a layer (L1, L2, L3, L4), wherein - the stator (1) has a multiplicity of turns (41, 42), which extend over the entire circumference of the stator (1) and thereby form a partial-coil, - in each case four pins (22, 23, 24, 25) in different layers (L1, L2, L3, L4) are connected to one another in series and form a first of the turns (41), - a first pin (25) of the first turn (41) is located in a first slot (53) in the first layer (L1), - a second pin (24) of the first turn (41) is located in a second slot (94) in the second layer (L2) and is connected to the first pin (25) on the second end face (9) by means of a first type of connection (61), wherein the second slot (94) is at a first radial distance (13) from the first slot (53) in a first circumferential direction of the stator (1), - a third pin (23) of the first turn (41) is located in the first slot (53) in the fourth layer (L4) and is connected to the second pin (24) on the first end face (7) by means of a second type of connection (62), - a fourth pin (22) of the first turn (41) is located in the second slot (94) in the third layer (L3) and is connected to the third pin (23) on the second end face (9) by means of a third type of connection (63), - the fourth pin (22) in the second slot (94) is connected to a fifth pin (26) in the first layer (L1) in a third slot (55) by means of a fourth type of connection (64) and there is a second distance (19) between the second slot (94) and the third slot (55), the second distance being greater than the first distance (13), - the series connection of the subsequent pins in the stator (1) begins again with the fifth pin (26), and - the first, the second and the third type of connection (61, 62, 63) differ from one another.

2. Stator (1) according to Claim 1, wherein two partial-coils are provided, which are connected to one another by means of a fifth type of connection (65) or a sixth type of connection (66) and form a coil (201, 202).

3. Stator (1) according to Claim 2, wherein four pins of a coil completely occupy four slots (92, 94, 96, 98).

4. Stator (1) according to Claim 3, wherein the stator (1) has three phases, wherein in each case two coils (201, 202) are assigned to one of the three phases in such a way that in each case two coils, which are assigned to the same phase, are located in three adjacent slots (51-58, 71-78, 91-98) and thus in each case two different layers of the two outer slots (71-78, 91-98) are occupied by pins of other phases.

5. Stator (1) according to Claim 8, wherein a respective input (81, 87, 101, 107, 111, 117) and a respective output (83, 103, 113, 85, 105, 115) of the at least two coils (201, 202) are connected to one another and the two coils (201, 202) are connected in parallel as a result.

6. Vehicle (403) having an electric machine (401) with a stator (1) according to one of the preceding claims.