Stator arrangement for the electrical device

Abstract

Stator assembly (12) for an electrical device, the stator assembly (12) comprising: a stator core (20) defining a plurality of slots (22) spaced apart from one another; a plurality of bar conductors (24) disposed in each of the slots (22) and arranged to represent a first winding path, a second winding path, and a third winding path, wherein a first set of the bar conductors (24) of the first, second, and third winding paths are configured to receive current in a parallel circuit arrangement; and a plurality of electrical bridges (60) electrically connected to a predetermined number of the bar conductors (24) such that an amount of current flowing through the first winding path and through the third winding path is substantially the same, and an amount of current flowing through the second winding path is different from the amount of current flowing through the first and third winding paths; characterized in that the stator core (20) extends between a first end (32) and a second end (34) along a longitudinal axis (18), and the stator core (20) includes an inner wall (36) defining a hole (38) along the longitudinal axis (18) such that the inner wall (36) is radially spaced from the longitudinal axis (18), and wherein the stator core (20) includes an outer wall (40) opposite the inner wall (36); wherein the slots (22) are spaced radially from one another about the longitudinal axis (18) and each extends between the first and second ends (32, 34) of the stator core (20); wherein each of the grooves (22) includes an inner layer (42) of the bar conductors (24) disposed proximal to the inner wall (36), an outer layer (44) of the bar conductors (24) disposed proximal to the outer wall (40) and spaced from the inner layer (42), and a middle layer (46) of the bar conductors (24) disposed between the inner and outer layers (42, 44); wherein the inner layer (42) of each groove includes a first layer (48) and a second layer (50), the middle layer (46) of each groove includes a third layer (52) and a fourth layer (54), and the outer layer (44) of each groove includes a fifth layer (56) and a sixth layer (58), the six layers (48-58) being arranged in a row from the inner wall (36) outwardly toward the outer wall (40) such that the first layer (48) is arranged proximal to the inner wall (36) and the sixth layer (58) is arranged proximal to the outer wall (40); and wherein a first of the electrical bridges (86) connects the inner and outer layers (42, 44) to form the first winding path, a second of the electrical bridges (88) connects the inner and outer layers (42, 44) to form the third winding path, and a third of the electrical bridges (90) connects the middle layer (46) to form the second winding path.

Description

TECHNICAL FIELD

[0001] The present invention relates to a stator arrangement according to the preamble of claim 1 for an electrical device, as is essentially known from DE 103 31 841 B4. Further prior art can be found in the documents US 2005 / 0 212 372 A1, DE 10 2014 100 410 A1 and JP 2009 - 254 135 A. BACKGROUND

[0002] Electric vehicles may include an electric machine that generates torque. The electric machine may be configured to use an AC voltage from a vehicle inverter to generate rotary motion. The electric machine may include a rotor and a stator, the rotor being rotatable relative to the stator when the electric machine uses the AC voltage. The stator may include a plurality of bar conductors arranged in slots to arrange winding paths in a parallel circuit configuration that produces a balanced or equal amount of current flowing through each of the winding paths. Each of the winding paths produces a waveform that is exactly the same size as, and exactly in phase with, every other waveform when in a balanced configuration, which may cause resonance, producing acoustic noise.In addition, a balanced arrangement can lead to hot spots in the stator where there is limited access to cooling the stator. SUMMARY

[0003] According to the invention, a stator arrangement for an electrical device is presented, which is characterized by the features of claim 1.

[0004] Also described is an electrical device that includes a housing and a rotor rotatably supported by the housing. The electrical device also includes a stator assembly supported by and secured to the housing. The stator assembly includes a stator core defining a plurality of slots spaced apart from one another. The stator assembly also includes a plurality of bar conductors disposed in each of the slots and arranged to constitute a first winding path, a second winding path, and a third winding path. A first set of the bar conductors from each of the first, second, and third winding paths is configured to receive current in a parallel circuit arrangement.The stator assembly further includes a plurality of electrical bridges electrically connected to a predetermined number of the bar conductors such that an amount of current flowing through the first winding path and through the third winding path is substantially the same, and that an amount of current flowing through the second winding path is different from the amount of current flowing through the first and through the third winding path.

[0005] The detailed description and the drawings or figures support and describe the invention. While some of the best modes and other embodiments for carrying out the claims have been described in detail, various alternative designs and embodiments exist for practicing the invention defined in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic plan view of an electrical device. Fig. 2 is a schematic, partially exploded perspective view of a stator assembly and a rotor. Fig. 3 is a schematic exploded perspective view of a connection support structure compatible with a stator core. Fig. 4 is a fragmentary end view of the stator core defining a plurality of slots. Fig. Figure 5 is a schematic plan view of the stator assembly of Fig. 2 and Fig. 3. Fig. 6 is a schematic diagram of one embodiment of a first waveform and a third waveform that are out of phase with a second waveform. Fig. 7 is a schematic diagram of another embodiment of the first waveform and the third waveform that are out of phase with the second waveform. Fig. 8 is a schematic wiring diagram of an embodiment for a plurality of winding paths for a U-phase. Fig. 9 is a schematic wiring diagram of another embodiment for a plurality of winding paths for a U-phase. DETAILED DESCRIPTION

[0006] With reference to the figures, in which like reference characters designate like or corresponding parts throughout the several views, Fig. 1 generally shows an electrical device 10 and a stator assembly 12 for the electrical device 10. Therefore, the electrical device 10 may include the stator assembly 12.

[0007] The electrical device 10 may be used in a vehicle. The vehicle may be a passenger vehicle or a commercial vehicle. For example, the vehicle may be a battery electric vehicle, a hybrid electric vehicle including a plug-in hybrid electric vehicle, an extended-range electric vehicle, or any other suitable vehicles.

[0008] The electrical device 10 may include an electric motor, a drive motor, or other similar device. The electrical device 10 may be, for example, a permanent magnet motor, an induction motor, a synchronous motor, etc. The electrical device 10 may include any device configured to generate electrical machine torque, for example, by converting electrical energy into rotational motion. The electrical device 10 may be configured to receive electrical energy from a power source, such as a battery pack. The power source may be configured to store and output electrical energy.

[0009] The vehicle may include an inverter to convert the direct current (DC) voltage from the battery pack into an alternating current (AC) voltage. The electrical device 10 may be configured to use the AC voltage from the inverter to generate rotary motion. The electrical device 10 may also be configured to generate electrical energy when supplied with mechanical energy, such as the mechanical energy (torque) of a prime mover.

[0010] With reference to Fig. 1, the electrical device 10 may include a housing 14. The housing 14 may be made of any suitable material, including aluminum, and may comprise any suitable size, shape, and / or configuration suitable to house the internal components of the electrical device 10, some of which are discussed below. For example, the stator assembly 12 is supported by the housing 14. In particular, the stator assembly 12 is fixed to the housing 14. In other words, the stator assembly 12 is stationary with respect to the housing 14.

[0011] With reference to Fig. 1 and Fig. 2, the electrical device 10 also includes a rotor 16 that is rotatably supported by the housing 14. The rotor 16 is rotatable relative to the stator assembly 12 about a longitudinal axis 18. The rotor 16 may, for example, include windings or permanent magnets that interact with the poles of the stator assembly 12 to generate rotation of the rotor 16 relative to the stator assembly 12. The rotor 16 may be a rotor with internal permanent magnets, a rotor with permanent magnets on the surface, an induction rotor, a synchronous rotor, a reluctance rotor, or a separately excited / wound field rotor. The rotor 16 is shown only for illustration purposes in Fig. 1 and Fig. 2 shown schematically.

[0012] With reference to Fig. 3 and Fig. 4, the stator assembly 12 further includes a stator core 20 defining a plurality of slots 22 (see Fig. 4) which are spaced apart from each other. The stator assembly 12 also includes a plurality of bar conductors 24 (see Fig. 2, Fig. 3 and Fig. 5) disposed in each of the slots 22 and arranged to constitute a first winding path, a second winding path, and a third winding path. A first set of the bar conductors 24a of the first, second, and third winding paths is configured to receive a current in a parallel circuit arrangement. Therefore, currents entering the first, second, and third winding paths are in a parallel electrical circuit, not a series circuit arrangement. In other words, the same voltage potential enters the first, second, and third winding paths. The location of the first set of bar conductors 24a of the first, second, and third winding paths may be different in the two embodiments discussed herein.The electrical device 10 may be operated in response to a voltage applied by the inverter to the winding paths, thereby generating a torque-generating current in the winding paths, causing rotation of the rotor 16. The bar conductors 24 are sometimes referred to as hairpin conductors, and they may have a substantially rectangular cross-section.

[0013] With reference to Fig. 2, the stator core 20 extends along the longitudinal axis 18 between a first end 32 and a second end 34. The slots 22 are radially spaced apart from each other around the longitudinal axis 18 and each extends between the first and second ends 32, 34 of the stator core 20. Therefore, the slots 22 may extend longitudinally along the longitudinal axis 18. In certain embodiments, there are exactly seventy-two slots 22 defined in the stator core 20, and the stator core 20 defines eight poles.

[0014] As in Fig. 2, the stator core 20 may include an inner wall 36 defining a hole 38 along the longitudinal axis 18 such that the inner wall 36 is radially spaced from the longitudinal axis 18. The rotor 16 is disposed within the hole 38 of the stator core 20 and may be rotated relative to the inner wall 36 of the stator core 20 when current is flowing through the stator core 20. Additionally, the slots 22 may intersect the inner wall 36.

[0015] With reference to Fig. 5, the stator core 20 may also include an outer wall 40 that is opposite the inner wall 36. Therefore, the inner wall 36 and the outer wall 40 are spaced apart transversely to the longitudinal axis 18. Consequently, the inner wall 36 defines an inner diameter, and the outer wall 40 defines an outer diameter that is larger than the inner diameter. The diameter of the stator core 20 increases from the inner wall 36 outward toward the outer wall 40.

[0016] With Fig. Continuing with FIG. 5, each of the slots 22 may include an inner layer 42 of the bar conductors 24 disposed proximal to the inner wall 36 and an outer layer 44 of the bar conductors 24 disposed proximal to the outer wall 40 and spaced from the inner layer 42. Additionally, each of the slots 22 may include a middle layer 46 of the bar conductors 24 disposed between the inner and outer layers 42, 44.

[0017] In the embodiment of Fig. 6 and Fig. 8 is generally a combination of certain bar conductors 24 of the inner and outer layers 42, 44 connected to the first and third winding paths and certain bar conductors 24 of the middle layer 46 are connected to the second winding path.

[0018] In addition, in the embodiment of Fig. 6 and Fig. 8, a current enters the first winding path through the inner layer 42, a current enters the second winding path through the middle layer 46, and a current enters the third winding path through the outer layer 44. As will be further discussed below, in the embodiment of Fig. 7 and Fig. 9, a combination of certain bar conductors 24 of the inner, outer, and middle layers 42, 44, 46 is generally connected to the first and third winding paths, and a combination of certain bar conductors 24 of the inner and middle layers 42, 44 is connected to the second winding path. In addition, in the embodiment of Fig. 7 and Fig. 9 a current enters the first and third winding paths through the outer layer 44 and a current enters the second winding path through the middle layer 46.

[0019] Generally, the current flowing through the inner layer 42 is proximal to the inner diameter of the inner wall 36 to present a first path distance, and it creates a first magnetic flux in the inner layer 42. Furthermore, the current flowing through the middle layer 46, which is spaced between the inner and outer walls 36, 40, presents a second path distance greater than the first path distance, and it creates a second magnetic flux in the middle layer 46 that is different from the first magnetic flux. Furthermore, the current flowing through the outer layer 44 is proximal to the outer diameter of the outer wall 40 to present a third path distance greater than the first path distance and than the second path distance, and it creates a third magnetic flux in the outer layer 44 that is different from the first and second magnetic flux.Therefore, when a current, such as an alternating current, flows through the inner layer 42, which is proximal to the inner wall 36 and travels around the stator core 20 with a smaller diameter than the middle and outer layers 46, 44, the distance the current travels is less than the distance the current travels for the outer layer 44 due to the outer layer 44 being proximal to the outer wall 40 and having a larger diameter. Consequently, the inductance experienced by the alternating current in the inner layer 42 is different from the inductance in the outer and middle layers 44, 46. Therefore, the different path distances of the current around the stator core 20 and the different inductances of the inner, outer, and middle layers 42, 44, 46 create differences in the impedance of the layers 42, 44, 46.However, with the connections of the various bar conductors 24 of the various layers 42, 44, 46, which are further described below, the differences in impedance can be reduced or minimized.

[0020] With reference to Fig. 4, the inner layer 42 of each of the grooves 22 may include a first layer 48 and a second layer 50. The middle layer 46 of each of the grooves 22 may include a third layer 52 and a fourth layer 54. The outer layer 44 of each of the grooves 22 may include a fifth layer 56 and a sixth layer 58. The first, second, third, fourth, fifth, and sixth layers 48, 50, 52, 54, 56, 58 are arranged in a row from the inner wall 36 outward toward the outer wall 40 such that the first layer 48 is disposed proximal to the inner wall 36 and the sixth layer 58 is disposed proximal to the outer wall 40. Therefore, each of the grooves 22 includes six layers 48, 50, 52, 54, 56, 58.The stator assembly 12 may include insulation disposed between each of the bar conductors 24 of each of the slots 22 to prevent unwanted electrical connection between the bar conductors 24 of the layers 48, 50, 52, 54, 56, 58 in the same slot 22, ie, to prevent a short circuit.

[0021] As in Fig. 2, Fig. 3, Fig. 8 and Fig. 9, the stator assembly 12 also includes a plurality of electrical bridges 60 electrically connected to a predetermined number of the bar conductors 24 such that an amount of current flowing through the first winding path and through the third winding path is substantially equal. In other words, the amount of current flowing through the first and third winding paths is substantially balanced, ie, substantially the same amount (see also Fig. 6 and Fig. 7). With Fig. 6 and Fig. 7, the current flowing through the second winding path differs from the current flowing through the first and third winding paths. Therefore, the arrangement of the stator core 20 is partially unbalanced due to the fact that the current flowing through the second winding path differs from that of the first and third winding paths. The diagrams of Fig. 6 and Fig. 7 are labeled in units of amperes (A) for current and milliseconds (ms) for time.

[0022] In certain embodiments, with reference to Fig. 6, the amount of current flowing through each of the first and third winding paths is greater than the amount of current flowing through the second winding path. Therefore, the amount of current flowing through the inner and outer layers 42, 44 is greater than the amount of current flowing through the middle layer 46. Because the electrical bridges 60 electrically connect certain bar conductors 24 of the inner and outer layers 42, 44 of this embodiment, the flow of the inner and outer layers 42, 44 is substantially equal, i.e., substantially balanced, which also substantially balances the impedance of these layers 42, 44.Heat generated in the first and third winding paths is greater than the heat generated in the second winding path because the amount of current flowing through the first and third winding paths is greater than the amount of current flowing through the second winding path. Therefore, more heat is generated in the inner and outer layers 42, 44 due to the greater amount of current flowing through these layers 42, 44 than in the middle layer 46 of this embodiment. However, because the location of the inner layer 42 is adjacent to the inner wall 36 and the outer layer 44 is adjacent to the outer wall 40, the inner and outer layers 42, 44 can be easily cooled.Therefore, coolant conduits filled with a coolant fluid may be disposed proximal to the inner wall 36 and the outer wall 40 to cool the inner and outer layers 42, 44 of this embodiment. Because the middle layer 46 is inherently cooler than the inner and outer layers 42, 44, hot spots are minimized. Consequently, the configuration of the stator assembly 12 having the waveforms 62, 64, 66 of FIG. Fig. 6, which are discussed in detail below, exhibit improved thermal performance.

[0023] In other embodiments with reference to Fig. 7, the current flowing through each of the first and third winding paths is less than the current flowing through the second winding path. Therefore, the current flowing through the inner, outer, and middle layers 42, 44, 46, which create the first and third winding paths, is less than the current flowing through the inner and middle layers 42, 46, which create the second winding path. Because the electrical bridges 60 electrically connect certain bar conductors 42 of the inner, outer, and middle layers 42, 44, 46 to create the first and third winding paths of this embodiment, the flux of the inner, outer, and middle layers 42, 44, 46 of the first and third winding paths is substantially equal, ie, substantially balanced, which also substantially balances the impedance of these layers 42, 44, 46 of the first and third winding paths.

[0024] With reference to Fig. 6 and Fig. 7, the current flowing through the first winding path generates a first waveform 62, the current flowing through the second winding path generates a second waveform 64, and the current flowing through the third winding path generates a third waveform 66. As in Fig. 6 and Fig. As shown in Figure 7, the first and third waveforms 62, 66 are substantially the same, and the second waveform 64 differs from the first and third waveforms 62, 66. Consequently, the second waveform 64 of the current flowing through the second winding path has a phase shift relative to the first and third waveforms 62, 66 of the current flowing through the first and third winding paths. By creating the phase shift, acoustic noise is minimized because the frequencies of the waveforms 62, 64, 66 are spread. Fig. 6 and Fig. The waveforms 62, 64, 66 shown in Figure 7 are for illustrative purposes only and the waveforms 62, 64, 66 may have minor deviations than shown.

[0025] As above for Fig. 6, the amount of current flowing through each of the first and third winding sections is greater than the amount of current flowing through the second winding section. As in Fig. 6, a peak amplitude 68 of the first and third waveforms 62, 66 occurs in time before a peak amplitude 70 of the second waveform 64, so that the first and third waveforms 62, 66 differ from the second waveform 64.

[0026] The peak amplitude 70 of the current from Fig. 6, which flows through the second winding section, is smaller than the peak amplitude 68 of the current flowing through the other winding sections, which creates the partially unbalanced winding. In addition, the peak amplitude 70 of the current from Fig. 6 flowing through the second winding section is phase-shifted to the peak amplitude 68 of the current flowing through the first and third winding sections, which, as discussed above, minimizes acoustic noise. In other words, as in Fig. 6, a phase shift between the peak amplitude 70 of the current flowing through the second winding section and the peak amplitude 68 of the current flowing through the first and third winding sections.

[0027] As above for Fig. 7, the current flowing through each of the first and third winding sections is smaller than the current flowing through the second winding section. Therefore, as shown in Fig. 7, a peak amplitude 72 of the first and third waveforms 62, 66 occurs temporally after a peak amplitude 74 of the second waveform 64, so that the first and third waveforms 62, 66 differ from the second waveform 64. The current magnitude of Fig. 7 flowing through the second winding section is greater than the current flowing through the other winding sections, creating the partially unbalanced winding. Furthermore, the peak amplitude 74 of the current from Fig. 7 flowing through the second winding section is phase-shifted to the peak amplitude 72 of the current flowing through the first and third winding sections, which, as discussed above, minimizes acoustic noise. In other words, as in Fig. 7, a phase shift between the peak amplitude 74 of the current flowing through the second winding path and the peak amplitude 72 of the current flowing through the first and third winding paths.

[0028] Again with reference to the electrical bridges 60, as in Fig. 3, Fig. 8 and Fig. 9, a plurality of electrical bridges 60 are illustrated and connected to particular bar conductors 24 to produce substantially the same amount of current flowing through the first and third winding paths and a different amount of current flowing through the second winding path. The first, second, and third winding paths create a three-phase electrical device 10 having a U-phase 76, a V-phase 78, and a W-phase 80. Therefore, a current in the U-phase 76 is divided among the first, second, and third winding paths, and the electrical bridges 60 are connected to particular bar conductors 24 of particular layers 42, 44, 46 such that the current in the U-phase 76 flows in a particular arrangement around the stator core 20.Similarly, a current in the V-phase 78 is divided between the first, second, and third winding sections, and other electrical bridges 60 are connected to specific bar conductors 24 of specific layers 42, 44, 46 such that the current in the V-phase 78 flows in a specific arrangement around the stator core 20. Furthermore, a current in the W-phase 80 is divided between the first, second, and third winding sections, and yet further electrical bridges 60 are connected to specific bar conductors 23 of specific layers 42, 44, 46 such that the current in the W-phase 80 flows in a specific arrangement around the stator core 20.

[0029] With reference to Fig. 8 and Fig. 9 shows the schematic plans of two winding layouts for the U-phase 76. The winding layout of Fig. 8 corresponds to waveforms 62, 64, 66, which are shown in Fig. 6 are generated, and the winding layout of Fig. 9 corresponds to waveforms 62, 64, 66, which are shown in Fig. 7. The winding layouts for the V-phase 78 and for the W-phase 80 are analogous to the U-phase 76 of these respective winding layouts, with the electrical bridges 60 shifted to other slots 22, and therefore the winding layouts are not shown. The basic structure of the rotor 16, the stator core 20 with the bar conductors 24 arranged in the layers 42, 44, 46, and with the slots 22 of the stator core 20, as described above, is suitable for both Fig. 8 as well as Fig. 9 are the same, whereby the differences between Fig. 8 and Fig. 9 are the special connection points of the electrical bridges 60.

[0030] The plans of Fig. 8 and Fig. 9 illustrate the first to sixth layers 48, 50, 52, 54, 56, 58 for each of the seventy-two slots 22 of the stator core 20. Fig. 8 and Fig. 9 also illustrate how many slots 22 each of the bar conductors 24 spans. In other words, each of the bar conductors 24 spans a predetermined number of slots 22, as in Fig. 8 and Fig. 9, and all the rod conductors 24 can have an identical span. Fig. 8 and Fig. 9, a starting connection 82, where current from the inverter enters the first set of bar conductors 24a and then flows around the stator core 20, and an ending connection 84, where the current exits a second set of bar conductors 24b and exits the stator core 20. Therefore, in both embodiments, current enters the stator core 20 through the first set of bar conductors 24a in the parallel circuit arrangement, and current exits the stator core 20 through the second set of bar conductors 24b.

[0031] The arrangement of the electrical bridges 60 of Fig. 8, which will be discussed in detail below, electrically connects a certain number of the bar conductors 24 such that the amount of current flowing through the inner and outer layers 42, 44 is substantially the same, while the amount of current flowing through the middle layer 46 differs from the amount of current flowing through the inner and outer layers 42, 44. Therefore, Fig. 8 different electrical bridges 60 are electrically connected to a predetermined number of the bar conductors 24 such that the current flowing through the first winding section and through the third winding section is substantially the same, and that the current flowing through the second winding section differs from the current flowing through the first and third winding sections. The arrangement of the electrical bridges 60, which is described below for Fig. 8 is for illustrative purposes only and other arrangements are possible.

[0032] With reference to Fig. 8, a first of the electrical bridges 86 is attached to the bar conductor 24 of the first layer 48 of one of the slots 22. In addition, the first of the electrical bridges 86 is attached to the bar conductor 24 of the sixth layer 58 of another of the slots 22 to cross the current between the inner and outer layers 42, 44. In particular, as shown in Fig. 8, one end of the first of the electrical bridges 86 is attached to the bar conductor 24 of the first layer 48 of the twenty-first slot 22, and another end of the first of the electrical bridges 86 is attached to the bar conductor 24 of the sixth layer 58 of the tenth slot 22. The first of the first bridges 86 connects the inner and outer layers 42, 44 to form the first winding path.

[0033] With Fig. Continuing with Figure 8, a second of the electrical bridges 88 is attached to the bar conductor 24 of the second layer 50 in the same groove 22 as the first of the electrical bridges 86 attached to the bar conductor 24 of the sixth layer 58. Furthermore, the second of the electrical bridges 88 is attached to the bar conductor 24 of the fifth layer 56 in the same groove 22 as the first of the electrical bridges 86 attached to the bar conductor 24 of the first layer 48 to cross the current between the inner and outer layers 42, 44. In particular, as shown in Fig. 8, one end of the second of the electrical bridges 88 is attached to the bar conductor 24 of the second layer 50 of the tenth slot 22, and another end of the second of the electrical bridges 88 is attached to the bar conductor 24 of the fifth layer 56 in the twenty-first slot 22. The second of the electrical bridges 88 connects the inner and outer layers 42, 44 to form the third winding path.

[0034] Again with Fig. Continuing with Figure 8, a third of the electrical bridges 90 is attached to the bar conductor 24 of the fourth layer 54 in the same groove 22 as the first of the electrical bridges 86 attached to the bar conductor 24 of the sixth layer 58. Furthermore, the third of the electrical bridges 90 is attached to the bar conductor 24 of the third layer 52 in the same groove 22 as the first of the electrical bridges 86 attached to the bar conductor 24 of the first layer 48. Therefore, the third of the electrical bridges 90 maintains the current in the middle layer 46. In particular, as shown in Fig. 8, one end of the third of the electrical bridges 90 is attached to the bar conductor 24 of the fourth layer 54 of the tenth slot 22, and another end of the third of the electrical bridges 90 is attached to the bar conductor 24 of the third layer 52 in the twenty-first slot 22. The third of the electrical bridges 90 connects the middle layer 46 to form the second winding path.

[0035] Fig. Figure 3 illustrates the first, second and third of the electrical bridges 86, 88, 90, which are duplicated twice at locations in different slots 22 around the stator core 20, as in Fig. 3. Therefore, the stator assembly 12 may further include a fourth of the electrical bridges 92, a fifth of the electrical bridges 94, a sixth of the electrical bridges 96, a seventh of the electrical bridges 98, an eighth of the electrical bridges 100, and a ninth of the electrical bridges 102. The fourth and fifth of the electrical bridges 92, 94 cross the current between the inner and outer layers 42, 44. Similarly, the seventh and eighth of the electrical bridges 98, 100 cross the current between the inner and outer layers 42, 44. The sixth and ninth of the electrical bridges 96, 102 maintain the current in the middle layer 46. Therefore, the locations of the electrical bridges 60 of Fig. 2, Fig. 3, Fig. 5 and Fig. 8 of the same embodiment.

[0036] The arrangement of the electrical bridges 60 for the U-phase 76 as described above for Fig. 8 is repeated for the V-phase 78, where the numbers of all slots 22 are increased by 120 electrical degrees. In the embodiment with seventy-two slots 22 and eight poles, which is compatible with Fig. 8, 120 electrical degrees are equal to an increase of six slots 22. Therefore, the location of the fourth, fifth and sixth of the electrical bridges 92, 94, 96 used for the V-phase 78 is shifted by six slots 22. In addition, the arrangement of the electrical bridges 60 for the U-phase 76 described above for Fig. 8 is repeated for the W phase 80, increasing the numbers of all slots 22 by 240 electrical degrees. For the embodiment with seventy-two slots 22 and eight poles, which lead to Fig. 8 is compatible, the 240 electrical degrees are equal to an increase of twelve slots 22. Therefore, the location of the seventh, eighth and ninth of the electrical bridges 98, 100, 102, which is used for the W phase 80, is shifted by twelve slots 22.

[0037] Three sets of three electrical bridges 86, 88, 90, 92, 94, 96, 98, 100, 102 can be used to conduct current through the first, second, and third winding paths in the respective U-phase 76, V-phase 78, and W-phase 80. For example, the first, second, and third of the electrical bridges 86, 88, 90 are arranged around the stator core 20 to conduct the current flowing through the first, second, and third winding paths in the U-phase 76. Similarly, the fourth, fifth, and sixth of the electrical bridges 92, 94, 96 are arranged around the stator core 20 to conduct the current flowing through the first, second, and third winding paths in the V-phase 78. In addition, the seventh, eighth, and ninth of the electrical bridges 98, 100, 102 are arranged around the stator core 20 to conduct the current flowing through the first, second, and third winding sections in the W phase 80.It should be appreciated that the sets of three electrical bridges 60 may be arranged differently than discussed immediately above, and that the U, V and W phases 76, 78, 80 may be arranged differently than discussed immediately above, and that this is a suitable example.

[0038] With reference to Fig. 9 shows another arrangement of the electrical bridges 60 for the U-phase 76. The arrangement of the electrical bridges 60 in this embodiment, as will be discussed in detail below, electrically connects a certain number of the bar conductors 24 such that the amount of current flowing through the inner, outer, and middle layers 42, 44, 46 of the first and third winding paths is substantially the same, while the amount of current flowing through the inner and middle layers 42, 46 of the second winding path differs from the amount of current flowing through the first and third winding paths. Therefore, in Fig. 9 different electrical bridges 60 are electrically connected to a predetermined number of the bar conductors 24 such that the amount of current flowing through the first winding section and through the third winding section is substantially the same, and that the amount of current flowing through the second winding section differs from the amount of current flowing through the first and through the third winding section. The following for Fig. The arrangement of the electrical bridges 60 discussed in Figure 9 is for illustrative purposes only, and other arrangements are possible. As mentioned above, the first, second, and third winding paths create a three-phase electrical device 10 with U-phase 76, V-phase 78, and W-phase 80.

[0039] With reference to Fig. 9, a first of the electrical bridges 104 is attached to the bar conductor 24 of the sixth layer 58 of one of the slots 22. In addition, the first of the electrical bridges 104 is attached to the bar conductor 24 of the fourth layer 54 of another of the slots 22 to cross the current between the outer and middle layers 44, 46. In particular, as shown in Fig. 9, one end of the first of the electrical bridges 104 is attached to the bar conductor 24 of the sixth layer 58 of the tenth slot 22 and another end of the first of the electrical bridges 104 is attached to the bar conductor 24 of the fourth layer 54 of the twenty-first slot 22.

[0040] With Fig. 9, a second of the electrical bridges 106 is attached to the bar conductor 24 of the fourth layer 54 in a different groove 22 than the first of the electrical bridges 104. Furthermore, the second of the electrical bridges 106 is attached to the bar conductor 24 of the second layer 50 in a different groove 22 than the first of the electrical bridges 104 to cross the current between the inner and middle layers 42, 46. In particular, as shown in Fig. 9, one end of the second of the electrical bridges 106 is attached to the bar conductor 24 of the fourth layer 54 of the twelfth slot 22, and another end of the second of the electrical bridges 106 is attached to the bar conductor 24 of the second layer 50 in the twentieth slot 22. The first and second of the electrical bridges 104, 106 respectively connect the outer layer 44 and the middle layer 46, and they connect the inner layer 42 and the middle layer 46 to form the first winding path.

[0041] Again with Fig. 9, a third of the electrical bridges 108 is attached to the bar conductor 24 of the third layer 52 in a different groove 22 than the first of the electrical bridges 104 and the second of the electrical bridges 106. Furthermore, the third of the electrical bridges 108 is attached to the bar conductor 24 of the fifth layer 56 in a different groove 22 than the first of the electrical bridges 104 and the second of the electrical bridges 106 to cross the current between the outer and middle layers 44, 46. In particular, as shown in Fig. 9, one end of the third of the electrical bridges 108 is attached to the bar conductor 24 of the third layer 52 of the nineteenth slot 22 and another end of the third of the electrical bridges 108 is attached to the bar conductor 24 of the fifth layer 56 in the twenty-eighth slot 22.

[0042] Again with Fig. 9, a fourth of the electrical bridges 110 is attached to the bar conductor 24 of the first layer 48 in the same groove 22 as an end of the first of the electrical bridges 104. Furthermore, the fourth of the electrical bridges 110 is attached to the bar conductor 24 of the third layer 52 in the same groove 22 as an end of the third of the electrical bridges 108 to cross the current between the inner and middle layers 42, 46. In particular, as in Fig. 9, one end of the fourth of the electrical bridges 110 is attached to the bar conductor 24 of the first layer 48 of the twenty-first slot 22, and another end of the fourth of the electrical bridges 110 is attached to the bar conductor 24 of the third layer 52 in the twenty-eighth slot 22. The third and fourth of the electrical bridges 108, 110 respectively connect the outer layer 44 and the middle layer 46, and they connect the inner layer 42 and the middle layer 46 to form the third winding path.

[0043] Again with Fig. 9, a fifth of the electrical bridges 112 is attached to the bar conductor 24 of the second layer 50 in a different slot 22 than the first, second, third, and fourth of the electrical bridges 104, 106, 108, 110. Furthermore, the fifth of the electrical bridges 112 is attached to the bar conductor 24 of the fourth layer 54 in a different slot 22 than the first, second, third, and fourth of the electrical bridges 104, 106, 108, 110 to cross the current between the inner and middle layers 42, 46. In particular, as shown in Fig. 9, one end of the fifth of the electrical bridges 112 is attached to the bar conductor 24 of the second layer 50 of the thirteenth slot 22 and another end of the fifth of the electrical bridges 112 is attached to the bar conductor 24 of the fourth layer 54 in the thirty-eighth slot 22.

[0044] Again with Fig. 9, a sixth of the electrical bridges 114 is attached to the bar conductor 24 of the first layer 48 in a different slot 22 than the first, second, third, fourth, and fifth of the electrical bridges 104, 106, 108, 110, 112. Furthermore, the sixth of the electrical bridges 114 is attached to the bar conductor 24 of the third layer 52 in a different slot 22 than the first, second, third, fourth, and fifth of the electrical bridges 104, 106, 108, 110, 112 to cross the current between the inner and middle layers 42, 46. In particular, as in Fig. 9, one end of the sixth of the electrical bridges 114 is attached to the bar conductor 24 of the first layer 48 of the thirty-seventh slot 22 and another end of the sixth of the electrical bridges 114 is attached to the bar conductor 24 of the third layer 52 of the forty-seventh slot 22.

[0045] Again with Fig. 9, a seventh of the electrical bridges 116 is attached to the bar conductor 24 of the second layer 50 in a different slot 22 than the first, second, third, fourth, fifth, and sixth of the electrical bridges 104, 106, 108, 110, 112, 114. Furthermore, the seventh of the electrical bridges 116 is attached to the bar conductor 24 of the first layer 48 in a different slot 22 than the first, second, third, fourth, fifth, and sixth of the electrical bridges 104, 106, 108, 110, 112, 114 to retain the current in the inner layer 42. In particular, as shown in Fig. As shown in Figure 9, one end of the seventh of the electrical bridges 116 is attached to the bar conductor 24 of the second layer 50 of the thirty-ninth slot 22, and another end of the seventh of the electrical bridges 116 is attached to the bar conductor 24 of the first layer 48 of the forty-sixth slot 22. The fifth and sixth of the electrical bridges 112, 114 both connect the middle layer 46 and the inner layer 42, and the seventh of the electrical bridges 116 is connected to the inner layer 42 to form the second winding path.

[0046] The first to seventh of the electrical bridges 104, 106, 108, 110, 112, 114, 116 are also used in the embodiment of Fig. 9 duplicated twice in different slots 22 around the stator core 20. Therefore, the stator assembly 12 may further include an eighth of the electrical bridges, a ninth of the electrical bridges, a tenth of the electrical bridges, an eleventh of the electrical bridges, a twelfth of the electrical bridges, a thirteenth of the electrical bridges, a fourteenth of the electrical bridges, a fifteenth of the electrical bridges, a sixteenth of the electrical bridges, a seventeenth of the electrical bridges, an eighteenth of the electrical bridges, a nineteenth of the electrical bridges, a twentieth of the electrical bridges, and a twenty-first of the electrical bridges.

[0047] The arrangement of the electrical bridges 60 for the U-phase 76, described above for Fig. 9 is repeated for the V-phase 78, increasing the numbers of all slots 22 by 120 electrical degrees. In the embodiment with seventy-two slots 22 and eight poles, which are connected to Fig. 9, the 120 electrical degrees are equal to an increase of six slots 22. Therefore, the location of the eighth, ninth, tenth, eleventh, twelfth, thirteenth and fourteenth of the electrical bridges used for the V-phase 78 is shifted by six slots 22. In addition, the arrangement of the electrical bridges 60 for the U-phase 76, which was described above for Fig. 9 is repeated for the W phase 80, with the numbers of all slots 22 being increased by 240 electrical degrees. In the embodiment with seventy-two slots 22 and eight poles, which is compatible with Fig. 9, the 240 electrical degrees are equal to an increase of twelve slots 22. Therefore, the location of the fifteenth, sixteenth, seventeenth, eighteenth, nineteenth, twentieth and twenty-first of the electrical bridges used for the W phase 80 is shifted by twelve slots 22.

[0048] Three sets of three electrical bridges 60 can be used to conduct current through the first, second, and third winding paths in the respective U-phase 76, V-phase 78, and W-phase 80. For example, the first through seventh of the electrical bridges 104, 106, 108, 110, 112, 114, and 116 are arranged around the stator core 20 to conduct current flowing through the first, second, and third winding paths into the U-phase 76. Similarly, the eighth through fourteenth of the electrical bridges are arranged around the stator core 20 to conduct current flowing through the first, second, and third winding paths in the V-phase 78. In addition, the fifteenth to twenty-first of the electrical bridges are arranged around the stator core 20 to conduct the current flowing through the first, second, and third winding sections in the W phase 80.It should be appreciated that the sets of three electrical bridges 60 may be arranged differently than discussed immediately above, and that the U, V and W phases 76, 78, 80 may be arranged differently than discussed immediately above, and that this is a suitable example.

[0049] The stator assembly 12 may also include a connection support structure 118 (see Fig. 2, Fig. 3 and Fig. 5), which can support various electrical bridges 60. For example, the connection support structure 118 has the first of the electrical bridges 86 and the second of the electrical bridges 88 attached thereto. The third of the electrical bridges 90 is separate from the connection support structure 118. In other words, the third of the electrical bridges 90 is not attached to the connection support structure 118. In other words, the third of the electrical bridges 90 can be spanned from one bar conductor 24 to another bar conductor 24 independently of the connection support structure 118 (see Fig. 2 and Fig. 3). Therefore, if, as in Fig. 2, the connection support structure 118 is spaced from the stator core 20, the third of the electrical bridges 90 will remain coupled to the stator core 20. Similarly, the fourth and fifth of the electrical bridges 92, 94 are attached to the connection support structure 118, while the sixth of the electrical bridges 96 is separated from the connection support structure 118. Therefore, the sixth of the electrical bridges 96 is spanned independently of the connection support structure 118 from one bar conductor 24 to another bar conductor 24 (see Fig. 2 and Fig. 3). In addition, the seventh and eighth of the electrical bridges 98, 100 are attached to the connecting support structure 118, while the ninth of the electrical bridges 102 is separated from the connecting support structure 118. Consequently, the ninth of the electrical bridges 102 is spanned independently of the connecting support structure 118 from one bar conductor 24 to another bar conductor 24 (see Fig. 2 and Fig. 3).

[0050] The connection support structure 118 may include a plurality of terminals 120 that can transfer current into and out of the stator core 20. In other words, the terminals 120 can conduct current into the bar conductors 24 and through the stator core 20 and conduct current out of the bar conductors 24 and away from the stator core 20. The terminals 120 can be in electrical communication with the inverter.

[0051] The stator assembly 12 may further include a plurality of first stator connectors 122 (see Fig. 2 and Fig. 3), wherein one or more of the terminals 120 are electrically connected to the first stator connectors 122 to conduct or transmit current into the stator core 20. The first stator connectors 122 are attached to the connection support structure 118, and each of the first stator connectors 122 is attached to respective first sets of the bar conductors 24a to split the current into the parallel circuit arrangement for the first, second, and third winding runs. Therefore, current can flow into the stator core 20 through the start connection 82 by means of the first stator connectors 122. One of the first stator connectors 122 splits the current in the U-phase 76, another of the first stator connectors 122 splits the current in the V-phase 78, and another of the first stator connectors 122 splits the current in the W-phase 80.Therefore, current in the U phase 76 enters a first set of the bar conductors 24a of respective winding paths of the stator core 20 through one of the first stator connectors 122, current in the V phase 78 enters another first set of the bar conductors 24a of respective winding paths of the stator core 20 through another of the first stator connectors 122, and current in the W phase 80 enters yet another first set of bar conductors 24a of respective winding paths of the stator core 20 through yet another of the first stator connectors 122.

[0052] As in Fig. 3, each of the first stator connectors 122 may include an inlet 124 to receive the current from one or more of the terminals 120. Additionally, each of the first stator connectors 122 may include a plurality of first prongs 126 to divide the current into the first set of bar conductors 24a of the first, second, and third winding runs. One of the first prongs 126 of each of the first stator connectors 122 is attached to respective bar conductors 24 in the first winding run, another of the first prongs 126 of each of the first stator connectors 122 is attached to respective bar conductors 24 in the second winding run, and yet another of the first prongs 126 of each of the first stator connectors 122 is attached to respective bar conductors 24 in the third winding run. The first stator connectors 122 may be electrically connected to any suitable bar conductors 24, and the figures illustrate a suitable arrangement.

[0053] The stator assembly 12 may further include a plurality of second stator connectors 128 (see Fig. 2 and Fig. 3), wherein one or more of the terminals 120 are electrically connected to the second stator connectors 128 to conduct or transmit current out of the stator core 20. The second stator connectors 128 are attached to the connection support structure 118, and each of the second stator connectors 128 is attached to respective second sets of the bar conductors 24b to recombine the current that has been divided into each of the first, second, and third winding paths into a respective outlet 130 to conduct the current out of the stator core 20. Therefore, current can flow out of the stator core 20 through the end connection 84 and through the second stator connectors 128.One of the second stator connectors 128 recombines the current in the U-phase 76, another of the second stator connectors 128 recombines the current in the V-phase 78, and another of the second stator connectors 128 recombines the current in the W-phase 80. Therefore, current in the U-phase 76 exits a second set of the bar conductors 24b from respective winding paths of the stator core 20 through one of the second stator connectors 128, current in the V-phase 78 exits another second set of the bar conductors 24b from respective winding paths of the stator core 20 through another of the second stator connectors 128, and current in the W-phase 80 exits yet another second set of the bar conductors 24b from respective winding paths of the stator core 20 through yet another of the second stator connectors 128.

[0054] As in Fig. 3, each of the second stator connectors 128 may include the outlet 130 for transferring or conducting current out of the stator core 20. Additionally, each of the second stator connectors 128 may include a plurality of second prongs 132 that recombine current that has been divided into the second set of bar conductors 24b of the first, second, and third winding runs. One of the second prongs 132 of each of the second stator connectors 128 is attached to respective bar conductors 24 in the first winding run, another of the second prongs 132 of each of the second stator connectors 128 is attached to respective bar conductors 24 in the second winding run, and yet another of the second prongs 132 of each of the second stator connectors 128 is attached to respective bar conductors 24 in the third winding run.The second stator connectors 128 may be electrically connected to any suitable bar conductors 24, and the figures illustrate a suitable arrangement.

[0055] The connection support structure 118 may further include an output bar 134, with the second stator connectors 128 attached to the output bar 134 in a spaced-apart relationship. In particular, the outlet 130 of each of the second stator connectors 128 is attached to the output bar 134. The output bar 134 electrically connects all of the second stator connectors 128 to form a Y-connection. The output bar 134 is also electrically connected to one or more of the terminals 120. The output bar 134 may also be referred to as a neutral bar.

[0056] Different electrical bridges 60 can cross each other (see Fig. 3 and Fig. 5). At least one of these crossing electrical bridges 60 may contain an insulation 136 (as in Fig. 3) arranged therebetween to prevent an undesired electrical connection therebetween, ie, to prevent a short circuit. For example, the first and second of the electrical bridges 86, 88 (see Fig. 5) and therefore the first and / or the second of the electrical bridges 86, 88 may contain the insulation 136 therebetween. Similarly, the fourth and fifth of the electrical bridges 92, 94 (see Fig. 5) and therefore the fourth and / or fifth of the electrical bridges 92, 94 may contain the insulation 136 therebetween. In addition, the seventh and eighth of the electrical bridges 98, 100 (see Fig. 5) and therefore, the seventh and / or eighth of the electrical bridges 98, 100 may include the insulation 136 therebetween. Additionally or alternatively, the electrical bridges 60 that cross each other may be configured such that the electrical bridges 60 are spaced apart from each other without using the insulation 136.

[0057] As discussed above, the connection support structure 118 supports the first and second stator connectors 122, 128, the terminals 120, the output bar 134, and certain electrical jumpers 60, and these components are pre-assembled to the connection support structure 118. Therefore, during assembly of the stator assembly 12, the connection support structure 118 can be appropriately placed on the stator core 20 where the corresponding connections of the bar conductors 24 are located. Once the connection support structure 118 is positioned on the stator core 20, the connections can be welded together. For example, each of the first prongs 126 may be welded to the respective bar conductors 24, each of the second prongs 132 may be welded to the respective bar conductors 24, the electrical bridges 60 may be welded to the respective bar conductors 24, etc. In addition, the outlets 130 may be welded to the output bar 134.The connection support structure 118 provides a quick connection, rather than requiring each electrical bridge 60 / the first and second stator connectors 122, 128 to be placed individually. Therefore, the connection support structure 118 can help make the assembly of the stator assembly 112 efficient. It should be noted that the embodiment of FIG. Fig. 9, the connection support structure 118 and / or the first and second stator connectors 122, 128 may optionally be used at the desired location to accommodate this embodiment.

Claims

[1] Stator assembly (12) for an electrical device, the stator assembly (12) comprising: a stator core (20) defining a plurality of slots (22) spaced apart from one another; a plurality of bar conductors (24) disposed in each of the slots (22) and arranged to represent a first winding path, a second winding path, and a third winding path, wherein a first set of the bar conductors (24) of the first, second, and third winding paths are configured to receive current in a parallel circuit arrangement; and a plurality of electrical bridges (60) electrically connected to a predetermined number of the bar conductors (24) such that an amount of current flowing through the first winding path and through the third winding path is substantially the same, and an amount of current flowing through the second winding path is different from the amount of current flowing through the first and third winding paths; characterized by that the stator core (20) extends between a first end (32) and a second end (34) along a longitudinal axis (18), and the stator core (20) includes an inner wall (36) defining a hole (38) along the longitudinal axis (18) such that the inner wall (36) is radially spaced from the longitudinal axis (18), and wherein the stator core (20) includes an outer wall (40) opposite the inner wall (36); wherein the slots (22) are spaced radially from one another about the longitudinal axis (18) and each extends between the first and second ends (32, 34) of the stator core (20); wherein each of the grooves (22) includes an inner layer (42) of the bar conductors (24) disposed proximal to the inner wall (36), an outer layer (44) of the bar conductors (24) disposed proximal to the outer wall (40) and spaced from the inner layer (42), and a middle layer (46) of the bar conductors (24) disposed between the inner and outer layers (42, 44); wherein the inner layer (42) of each groove includes a first layer (48) and a second layer (50), the middle layer (46) of each groove includes a third layer (52) and a fourth layer (54), and the outer layer (44) of each groove includes a fifth layer (56) and a sixth layer (58), the six layers (48-58) being arranged in a row from the inner wall (36) outwardly toward the outer wall (40) such that the first layer (48) is arranged proximal to the inner wall (36) and the sixth layer (58) is arranged proximal to the outer wall (40); and wherein a first of the electrical bridges (86) connects the inner and outer layers (42, 44) to form the first winding path, a second of the electrical bridges (88) connects the inner and outer layers (42, 44) to form the third winding path, and a third of the electrical bridges (90) connects the middle layer (46) to form the second winding path. [2] Stator assembly (12) according to claim 1, wherein: the amount of current flowing through the first winding path generates a first waveform, the amount of current flowing through the second winding path generates a second waveform, and the amount of current flowing through the third winding path generates a third waveform; and the first and third waveforms are substantially the same and the second waveform is different from the first and third waveforms. [3] Stator assembly (12) according to claim 2, wherein: the amount of current flowing through each of the first and third winding sections is greater than the amount of current flowing through the second winding section; and a peak amplitude of the first and third waveforms occurs before a peak amplitude of the second waveform, so that the first and third waveforms differ from the second waveform. [4] The stator assembly (12) of claim 3, wherein, due to the amount of current flowing through the first and third winding paths being greater than the amount of current flowing through the second winding path, heat generated in the first and third winding paths is greater than heat generated in the second winding path. [5] Stator assembly (12) according to claim 2, wherein: the amount of current flowing through each of the first and third winding sections is less than the amount of current flowing through the second winding section; and a peak amplitude of the first and third waveforms occurs after a peak amplitude of the second waveform, so that the first and third waveforms differ from the second waveform. [6] Stator assembly (12) according to claim 1, wherein: a first of the electrical bridges (86) is attached to the bar conductor (24) of the first layer of one of the slots (22) and the first of the electrical bridges (86) is attached to the bar conductor (24) of the sixth layer (58) of another of the slots (22) to cross the current between the inner and outer layers (42, 44); and a second of the electrical bridges (88) is attached to the bar conductor (24) of the second layer (50) in the same groove as the first of the electrical bridges (86) attached to the bar conductor (24) of the sixth layer (58), and the second of the electrical bridges (88) is attached to the bar conductor (24) of the fifth layer (56) in the same groove as the first of the electrical bridges (86) attached to the bar conductor (24) of the first layer (48) to cross the current between the inner and outer layers (42, 44). [7] The stator assembly (12) of claim 6, wherein a third of the electrical bridges (90) is attached to the bar conductor (24) of the fourth layer in the same slot as the first of the electrical bridges (86) attached to the bar conductor (24) of the sixth layer, and the third of the electrical bridges (90) is attached to the bar conductor (24) of the third layer in the same slot as the first of the electrical bridges (86) attached to the bar conductor (24) of the first layer. [8] The stator assembly (12) of claim 7, further including a connection support structure to which the first of the electrical bridges (86) and the second of the electrical bridges (88) are attached, the third of the electrical bridges (90) being separate from the connection support structure.

Images