Low-inductance bus bar assembly for an electric drive unit

Abstract

A bus bar assembly for use in a vehicle includes a direct current (DC) link busbar, configured to electrically couple to a vehicle battery and a plurality of switches implementing an inverter, conducting electrical current to an electric motor of the vehicle, comprising a plurality of DC electrical conductors having a shape that is substantially symmetrical, wherein the electrical conductors are stacked such that adjacent DC electrical conductors have opposite polarities; a phase busbar, adjacent to the DC link busbar, configured to electrically couple the plurality of switches to a stator of the electric motor; and a DC link connector, extending radiallyoutwardly away from the DC link busbar, configured to electrically couple the DC link busbar with bulk capacitance.

Description

4.560 (8887-3395002) LOW-INDUCTANCE BUS BAR ASSEMBLY FOR AN ELECTRIC DRIVE UNIT PRIORITY CLAIM

[0001] The present application claims priority to U.S. provisionalapplication no. 63 / 564,625 filed March 13, 2024 the entire contents of which are incorporated by reference. TECHNICAL FIELD

[0002] The present application relates to electric drive units used in batteryelectric vehicles (BEV) and, more particularly, to bus bar assemblies used in the electric drive units. BACKGROUND

[0003] Modern BEVs include an array of electrical components that are usedto convert stored electrical power into electricity that selectively powers the vehicle. The BEV can include a vehicle battery storing the electrical power and power electronics that convert the stored electrical power into electrical current for a rotating electric machine that propels the BEV. The efficiency with which the electrical components carry out this conversion can greatly affect the range and performance of the BEV. It would be helpful to improve the configuration of the electrical components to increase BEV performance and / or more efficiently use the electrical power stored in the vehicle battery. SUMMARY

[0004] In one implementation, a bus bar assembly for use in a vehicleincludes a direct current (DC) link busbar, configured to electrically couple to a vehicle battery and a plurality of switches implementing an inverter, conducting electrical current to an electric motor of the vehicle, comprising a plurality of DC4.560 (8887-3395002) electrical conductors having a shape that is substantially symmetrical, wherein the electrical conductors are stacked such that adjacent DC electrical conductors have opposite polarities; a phase busbar, adjacent to the DC link busbar, configured to electrically couple the plurality of switches to a stator of the electric motor; and a DC link connector, extending radially-outwardly away from the DC link busbar, configured to electrically couple the DC link busbar with bulk capacitance.

[0005] In another implementation, a bus bar assembly for use in a vehicle,includes a substrate having apertures positioned around the circumference of the substrate; a plurality of switches carried by the substrate, having pins extending through the apertures, implementing an inverter; a direct current (DC) link busbar, configured to electrically couple to a vehicle battery and the plurality of switches, conducting electrical current to an electric motor of the vehicle, comprising a plurality of DC electrical conductors having a shape that is substantially symmetrical, wherein the electrical conductors are stacked such that adjacent DC electrical conductors have opposite polarities; a phase busbar, adjacent to the DC link busbar, configured to electrically couple the plurality of switches to a stator of the electric motor; and a DC link connector, extending radially-outwardly away from the DC link busbar, configured to electrically couple the DC link busbar with bulk capacitance. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 is an exploded view depicting an implementation of a portionof a bus bar assembly used with an electric drive unit;

[0007] Figure 2 is a perspective view depicting an implementation of a busbar assembly used with an electric drive unit;

[0008] Figure 3 is an exploded view depicting an implementation of a portionof a bus bar assembly used with an electric drive unit;

[0009] Figure 4 is a perspective view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit;4.560 (8887-3395002)

[0010] Figure 5 is perspective view depicting an implementation of a portionof a bus bar assembly used with an electric drive unit;

[0011] Figure 6 is a perspective view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit;

[0012] Figure 7 is perspective view depicting an implementation of a portionof a bus bar assembly used with an electric drive unit;

[0013] Figure 8 is perspective view depicting an implementation of a portionof a bus bar assembly used with an electric drive unit;

[0014] Figure 9 is perspective view depicting an implementation of a portionof a bus bar assembly used with an electric drive unit;

[0015] Figure 10 is a plan view depicting an implementation of a bus barassembly used with an electric drive unit;

[0016] Figure 11 is a perspective view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit;

[0017] Figure 12 is a perspective view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit;

[0018] Figure 13 is a perspective view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit;

[0019] Figure 14 is a cross-sectional view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit;

[0020] Figure 15 is a perspective and partial cross-sectional view depictingan implementation of a portion of a bus bar assembly used with an electric drive unit;

[0021] Figure 16 is a perspective view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit;

[0022] Figure 17 is a cross-sectional view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit;

[0023] Figure 18 is a perspective view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit;

[0024] Figure 19 is a perspective view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit;4.560 (8887-3395002)

[0025] Figure 20 is a cross-sectional view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit;

[0026] Figure 21 is a perspective view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit;

[0027] Figure 22 is a cross-sectional view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit; and

[0028] Figure 23 is a cross-sectional view depicting an implementation of aportion of a bus bar assembly used with an electric drive unit. DETAILED DESCRIPTION

[0029] Electric drive units typically include a battery, supplying directcurrent (DC) electrical power to a rotating electrical machine or electric motor through a bus bar assembly, and power electronics that include an inverter. An example of such an electric drive unit is described in U.S. Patent No. 11,863,046 the entire contents of which are incorporated by reference. The bus bar assembly described here can be used with an electric drive unit. The bus bar assembly can include electrical conductors electrically coupled: in between the battery and the inverter via a DC link bus bar, to the stator wires of the electric motor via a phase bus bar, and in parallel to bulk capacitance through a DC link connector. As the inverter draws electrical current from the battery, an electromagnetic field (EMF) can be created by the flow of current through the bus bar assembly. The inductance of the bus bar assembly can be represented as a ratio of the magnetic flux relative to the amount of electrical current carried through the bus bar assembly. The existence of EMF resulting from the flow of electrical current may be unwanted, as increased EMF can increase the amount of inductance of the bus bar assembly.

[0030] A bus bar assembly can minimize inductance with a chosenconfiguration and arrangement of electrical conductors. For example, the bus bar assembly can include a substrate that receives a stack up of substantially symmetrically shaped electrical conductors having alternating polarities. The stack up can include DC electrical conductors that electrically couple the battery4.560 (8887-3395002) to the inverter as well as an AC or phase bus bar that electrically couples the inverter to the stator windings of the electric motor. The electrical connectors of the DC electrical conductors or phase bus bar that can electrically couple to switches of the inverter or the stator windings can also be sized and shaped in a way that minimizes or reduces overall inductance of the bus bar assembly. In some implementations, the electrical connectors can have increased width, thickness, and / or a contoured terminal shape to reduce inductance. The bus bar assembly can employ a layered and laminated configuration having a portion including ring-shaped electrical conductors with alternating polarities along with relatively thin insulation layers separating the electrical conductors. The electrical conductors having alternating positive and negative polarities can be formed to use the same shape and contours over the entire area of the conductors thereby further reducing inductance of the bus bar assembly. The ring shape portion of the electrical conductors can position a plurality of MOSFET switches included in the inverter back-to-back so that the body of the switches abut each other. In addition, the bus bar assembly can electrically couple with the bulk capacitance arranged symmetrically using the DC electrical conductors and the DC link connector. The combination of these features can significantly reduce the overall inductance of the bus bar assembly.

[0031] Turning to Figures 1-12, an implementation of a bus bar assembly 10is shown. The bus bar assembly 10 can include a substrate 12 that carries a DC link bus bar 14, a phase bus bar 16, and a plurality of electrical switches 18 used, at least partially, to implement an inverter. The substrate 12 can have a substantially circular shape and be formed from an electrically insulating material. A plurality of apertures 20 can be formed around the circumference of the substrate 12. The apertures 20 can be shaped to receive terminals of the switches 18 used to implement the inverter. In one implementation, the switches 18 are implemented using SiC MOSFET switches. For example, the switches 18 could be implemented using TO-247 MOSFETs each having four pins 22, such that the substrate 12 can have the apertures 20 positioned in a line extending radially- outwardly to accommodate the pins 22 of the MOSFETs. The apertures 20 can be shaped and located in the substrate 12 such that the MOSFETs can be positioned4.560 (8887-3395002) adjacent to each other around an outer diameter 24 of the substrate 12 on one side of the substrate 12 such that the bodies of adjacent MOSFETs abut each other in a way that the portion of the MOSFET having the largest surface area contact each other. The pins 22 of the MOSFETs can pass through the apertures 20 so that the pins 22 are exposed on an opposite side of the substrate 12.

[0032] The DC link bus bar 14 can electrically couple the battery to theinverter. The DC link bus bar 14 can be positioned on the opposite side of the substrate 12 so that the pins 22 of the MOSFETs can electrically couple to DC electrical conductors 26. The DC link bus bar 14 can include a plurality of DC electrical conductors 26, a portion of which each has a substantially similar circular or ring-shaped structure. The contour of an outer diameter 28 of the DC electrical conductors 26 can each be unform such that one DC electrical conductor 26 has the same outer diameter 28 and contour as another DC electrical conductor 26. With regard to implementations of DC electrical conductors 26 having inner diameters 30, the inner diameter 30 and contour can match as well. At one point along the outer diameter 28 of the DC electrical conductor 26, a substantially planar DC link connector 32 can extend radially-outwardly from the DC electrical conductors 26. The planar DC link connector 32 can electrically couple in parallel to bulk capacitance 44. The DC link connector 32 will be discussed in more detail below. The plurality of DC electrical conductors 26 can be separated by relatively thin electrical insulation layers 34. For example, the electrical insulation layers 34 can comprise a polymide film that is flexible, electrically insulating, and also withstands a wide range of temperatures. One implementation of the electrical insulation layer could be KaptonTMsold by DuPont. The thickness of the electrical insulation layer can be 0.25mm in one implementation.

[0033] A plurality of electrical connectors 36 can be positioned around theouter diameter 28 of the DC electrical conductors 26. The electrical connectors 36 can be integrally formed as part of the DC electrical conductors 26. In one implementation, the electrical connectors 36 can include radially-outwardly- extending sections 38 attached to individual tangs 40 that can be oriented substantially orthogonal to the radially-outwardly-extending sections 38. The4.560 (8887-3395002) tangs 40 can be positioned to be substantially parallel to the pins 22 of the switches 18 implemented as MOSFETs so that the tangs 40 can be electrically connected to the pins 22, via soldering, welding, or another type of electrically-conductive connection. The shape of the electrical connectors 36 can be chosen to help minimize the inductance of the bus bar assembly 10. For instance, the width (W) of the tangs 40 can be greater than the width (w) of the pins 22 helping to minimize the inductance of the bus bar assembly 10 by reducing a gap or space between adjacent tangs 40. In addition, the radially-outwardly-extending sections 38 can have an offset section 42 that positions a portion of the radially-outwardly- extending section 38 in a non-coaxial relationship with the remaining portion of the radially-outwardly-extending section 38. The offset section 42 can place adjacent tangs 40 nearer each other thereby reducing the gap or space between adjacent tangs 40, helping to reduce the overall inductance of the bus bar assembly 10.

[0034] An implementation of the DC link bus bar 14 includes a stack up(shown in Figure 10), extending from top to bottom, of the substrate 12, a first negative polarity DC electrical conductor 26a, an electrical insulation layer 34, a second negative polarity DC electrical conductor 26a, an electrical insulation layer 34, a first positive polarity DC electrical conductor 26b, an electrical insulation layer 34, a second positive polarity DC electrical conductor 26b, an electrical insulation layer 34, followed by the phase bus bar 16. The phase bus bar 16 can be positioned so that it abuts an electrical insulation layer 34 and is separated from the second positive polarity DC electrical conductor 26b by the electrical insulation layer 34. The position of the negative polarity DC electrical conductors 26a directly on top of the positive polarity electrical conductors 26b can reduce inductance of the bus bar assembly 10 by opposing the magnetic field created by the negative polarity DC electrical conductors 26a with the magnetic field created by the positive polarity DC electrical conductors 26b. That is, the magnetic field generated by the flow (or change in flow) of electrical current through the negative polarity DC link conductors 26a can be positioned 180 degrees relative to the magnetic field generated by the flow (or change in flow) of electrical current4.560 (8887-3395002) through the positive polarity DC link conductors 26b thereby counteracting each other.

[0035] An implementation of the portions 48 of the DC electrical conductors26 electrically coupled to the bulk capacitance 44 is shown in Figures 13-19. The portions 48 of the DC electrical conductors 26 can be coupled to ring-shaped portions of the DC electrical conductors 26 via the DC link connector 32. The DC link connector 32 can include planar areas of the DC electrical conductors 26 existing in the quantity and ordered according to the stack-up described above. In this implementation, the DC link connector 32 can include an electrically- conductive joint 50 that releasably connects discrete portions of the DC electrical conductors 26. However, as will be discussed below, the DC electrical conductors 26 can be formed as a unitary structure such that the DC electrical conductors 26 and the portions 48 coupled to the bulk capacitance 44 may be each be formed from a sheet of material, thereby omitting the electrically-conductive joint. The DC electrical conductors 26, along with electrical insulation layers 34 can include portions 48 that extend into a housing 46 that encloses the bulk capacitance 44. In this implementation, the DC link connector 32 and portions 48 of the DC electrical conductors 26 extending into the housing 46, are electrically coupled to the DC electrical conductors 26 via an electrically-conductive joint 50. The portions 48 include the first negative polarity DC electrical conductor 26a, the electrical insulation layer 34, the second negative polarity DC electrical conductor 26a, the electrical insulation layer 34, the first positive polarity DC electrical conductor 26b, the electrical insulation layer 34, and a second positive polarity DC electrical conductor 26b. The portions of the DC electrical conductors 26 and electrical insulation layers 34 extending within the housing 46 can be substantially symmetrical and have the same outer contours such that they fit inside the housing 46. As described above, the position of the negative polarity DC electrical conductors 26a directly on top of the positive polarity electrical conductors 26b can reduce inductance of the bus bar assembly 10 by opposing the magnetic field created by the negative polarity DC electrical conductors 26a with the magnetic field created by the positive polarity DC electrical conductors 26b. It is possible to reduce inductance of the bus bar assembly 10 by 33 percent or more.4.560 (8887-3395002)

[0036] The portion 48 of the DC electrical conductors 26 extends into thehousing 46 to be electrically coupled to the bulk capacitance 44 comprising a plurality of individual capacitors 54. The DC link 32 can extend for a length along an outer surface of the housing 46 before extending into the housing 46 and electrically connecting to the bulk capacitance 44. The DC link 32 can include angular bends that may be less than ninety degrees to facilitate the electrical connection between the portion 48 of the DC electrical conductors 26 extending into the housing 46 and the ring- or circular-shaped portions of the DC electrical conductors 26. The amount of angular bend having a value less than ninety degrees can minimize degradation of the electrical insulation layers 34.

[0037] The electrically-conductive joint 50 can be implemented in a numberof different ways. For example, end terminals 56 of the discrete portions of the DC electrical conductors 26 can be deflected or bent to be offset from corresponding end terminals 58 of the other discrete portions of the DC electrical conductors 26 so the end terminals 56, 58 abut each other and form an electrically conductive connection. In this implementation, end terminals 56 of the portion 48 of the DC electrical conductors 26 extending into the housing 46 can have an end terminal 56 of the first and second negative polarity DC conductors 26a and an end terminal 56 of the first and second positive polarity DC conductor 26b. The end terminals 56 of the negative polarity DC conductors 26 can be offset to be positioned in between end terminals 58 of corresponding negative polarity DC electrical conductors 26a. End terminals 56 of the portion 48 of the DC electrical conductors 26 extending into the housing 46 can have an end terminal 56 of the first positive polarity DC conductor 26b and an end terminal 56 of the second positive polarity DC conductor 26b that are positioned in between end terminals 58 of corresponding positive polarity DC electrical conductors 26b; one end terminal 58 can be offset to abut the second positive polarity DC conductor 26b. The electrical insulation layers 34 can be bonded to the DC conductors 26 using an adhesive to facilitate the electrically-conductive joint 50 and maintaining the electrical insulation layers 34 in proper orientation relative to the DC conductors 26.4.560 (8887-3395002)

[0038] The electrically-conductive joint 50 can be secured to the housing 46and the continuity of the electrical connections within the electrically-conductive joint 50 can be facilitated with a clamp bar assembly 60. The clamp bar assembly 60 includes a mounting location 62 on an outer surface of the housing 46 and an elongated clamp bar 64 that compresses the end terminals 56, 58 at the DC link connector 32 and draws the DC link connector 32 towards an outer surface of the housing 46, securing the DC link connector 32 against the housing 46. In one implementation, the mounting location 62 can include a plurality of ribs 66 that are formed on the outer surface of the housing 46 and extend linearly, perpendicularly with respect to the orientation of the elongated clamp bar 64. The ribs 66 can be raised above the outer surface of the housing 46 such that the DC link connector 32 can be pressed into the ribs 66 rather than the outer surface of the housing 46. In this implementation, the housing 46, including the ribs 66 can be formed from plastic, while the elongated clamp bar 64 may be formed from steel. However, it should be appreciated that other materials can be chosen for these elements. The mounting location 62 can include threaded receptacles 68 that may releasably receive threaded connectors 70, such as studs or bolts. The DC link connector 32 can be positioned over the ribs 66 such that the electrically- conductive joint 50 and the end terminals 56, 58 engage the ribs 66. The elongated clamp bar 64 can be positioned on a surface of the end terminals 56, 58 that is opposite the surface of the end terminals 56, 58 engaging the ribs.

[0039] The elongated clamp bar 64 can include apertures 72 for receivingthe threaded connectors 70, and one or more biasing features 74 that contact the end terminals 56, 58. The elongated clamp bar 64 can be stamped from an electrically conductive metal and the biasing features 74 can be integrally-formed from the stamped metal in the form of tangs 78 that extend away from the elongated clamp bar 64 and toward the end terminals 56, 58. The thickness, shape, and deflection angle of the tangs 78 can each be chosen or tuned to create a desired spring force. However, it should be appreciated that other implementations are possible in which the biasing features are formed independently from the elongated clamp bar. The threaded connectors 70, in this implementation threaded studs, can pass through the apertures 72 to engage the4.560 (8887-3395002) threaded receptacles 68. Threaded nuts 76 can engage the threaded connectors 70 to secure the elongated clamp bar 64 to the DC link connector 32 and the housing 46. As the threaded connectors 70 are tightened and draw the elongated clamp bar 62 closer to the ribs 66, the DC link connector 32 is secured to the housing 46, and the electrical connections between the end terminals 56, 58 can be secured, helping preserve electrical continuity between the discrete portions of the DC electrical conductors 26. In this implementation, the discrete portions of the DC electrical conductors 26 can later be separated by loosening the threaded nuts and separating the discrete portions of the DC electrical conductors at the electrically-conductive joint. However, other implementations are possible in which the end terminals 56, 58 are soldered or mechanically welded together.

[0040] Turning to Figures 20-22, another implementation of a housing 46’for the bulk capacitance 44 is shown. The housing 46’ includes locating features 80 that position the end terminals 56, 58 relative to each other and the housing 46’. In this implementation, the locating features 80 are positioned at the mounting location 62 and extend between the threaded connectors 70 as shown in Figure 21. A first locating feature 80a can be an elongated bar abutting the outer surface of the housing 46’ and having an outer surface that is configured to abut end terminals 56. A second locating feature 80b can be an elongated bar, similarly shaped as the first locating feature 80a, but spaced apart from the first locating feature 80a, extending between the threaded connectors 70, and also configured to abut end terminals 56. A third locating feature 80c can be an elongated bar spaced away and offset from the first and second locating features 80a, 80b, configured to be positioned in between the end terminals 56. The end terminals 56 can be placed adjacent to an outer surface of the housing 46’ so that they engage and are held fixed relative to the housing 46’ by the locating features 80. End terminals 58 can be moved into engagement with the end terminals 56, as well as with the locating features 80. The locating features 80 can position the end terminals 56 in an optimal location with respect to the elongated clamp bar 64 and the corresponding end terminals 58 to facilitate consistent and reliable electrical continuity between the end terminals 56, 58 when the elongated clamp bar 64 is secured.4.560 (8887-3395002)

[0041] Figure 23 depicts another implementation of a DC link bus bar 14’.The DC link bus bar 14’ includes a plurality of DC electrical conductors 26’ that are stacked having offsetting polarities as discussed above and also have a unitary and continuous structure. The DC electrical conductors 26’ are made from a unitary and uninterrupted sheet of material such that the portion 48 of the DC electrical conductors 14’ that couple with the bulk capacitance 44 can be implemented without using an electrically-conductive joint.

[0042] It is to be understood that the foregoing is a description of one or moreembodiments of the invention. The invention is not limited to the particular embodiment(s) disclosed herein, but rather is defined solely by the claims below. Furthermore, the statements contained in the foregoing description relate to particular embodiments and are not to be construed as limitations on the scope of the invention or on the definition of terms used in the claims, except where a term or phrase is expressly defined above. Various other embodiments and various changes and modifications to the disclosed embodiment(s) will become apparent to those skilled in the art. All such other embodiments, changes, and modifications are intended to come within the scope of the appended claims.

[0043] As used in this specification and claims, the terms "e.g.," “forexample,” “for instance,” “such as,” and “like,” and the verbs “comprising,” “having,” “including,” and their other verb forms, when used in conjunction with a listing of one or more components or other items, are each to be construed as open- ended, meaning that the listing is not to be considered as excluding other, additional components or items. Other terms are to be construed using their broadest reasonable meaning unless they are used in a context that requires a different interpretation.

Claims

4. 560 (8887-3395002) In the claims:

1. A bus bar assembly for use in a vehicle, comprising: a direct current (DC) link busbar, configured to electrically couple to a vehicle battery and a plurality of switches implementing an inverter, conducting electrical current to an electric motor of the vehicle, comprising a plurality of DC electrical conductors having a shape that is substantially symmetrical, wherein the electrical conductors are stacked such that adjacent DC electrical conductors have opposite polarities; a phase busbar, adjacent to the DC link busbar, configured to electrically couple the plurality of switches to a stator of the electric motor; and a DC link connector, extending radially-outwardly away from the DC link busbar, configured to electrically couple the DC link busbar with bulk capacitance.

2. The bus bar assembly recited in claim 1, wherein each of the DC electrical conductors has the same size inner diameter and outer diameter.

3. The bus bar assembly recited in claim 1, wherein the DC electrical conductors include a plurality of electrical connectors positioned around an outer diameter including tangs oriented orthogonal to the DC electrical conductors and configured to abut pins of the plurality of switches.

4. The bus bar assembly recited in claim 3, wherein the tangs have a width that is greater than a width of the pins.

5. The bus bar assembly recited in claim 1, further comprising a substrate, having a substantially circular shape and formed from an electrically-insulating material, having a plurality of apertures around a circumference of the substrate sized to receive pins of the plurality of switches and position the plurality of switches adjacent to each other along the circumference of the substrate.

6. The bus bar assembly recited in claim 1, wherein the DC electrical conductors are coupled to the tangs via an offset section.4.560 (8887-3395002) 7. The bus bar assembly recited in claim 1, wherein the plurality of DC electrical conductors comprise an ordered stack up of a first negative polarity electrical conductor, a second negative polarity conductor, a first positive polarity electrical conductor, and a second positive polarity electrical conductor.

8. The bus bar assembly recited in claim 1, wherein the DC link connector further comprises an electrically-conductive joint between the DC electrical conductors and portions of the DC link busbar electrically connected to the bulk capacitance.

9. The bus bar assembly recited in claim 8, wherein the electrically-conductive joint further comprises end terminals of discrete portions of the DC electrical connectors that are offset from corresponding end terminals of other portions of the DC electrical connectors.

10. The bus bar assembly recited in claim 8, wherein the electrically-conductive joint is secured to a housing with a clamp bar assembly.

11. The bus bar assembly recited in claim 1, wherein the DC link connector includes an angular bend.

12. The bus bar assembly recited in claim 1, further comprising a housing having at least one locating feature positioned at a mounting location for an electrically-conductive joint.

13. A bus bar assembly for use in a vehicle, comprising: a substrate having apertures positioned around the circumference of the substrate; a plurality of switches carried by the substrate, having pins extending through the apertures, implementing an inverter; a direct current (DC) link busbar, configured to electrically couple to a vehicle battery and the plurality of switches, conducting electrical current to an electric motor of the vehicle, comprising a plurality of DC electrical conductors having a shape that is substantially symmetrical, wherein the electrical4.560 (8887-3395002) conductors are stacked such that adjacent DC electrical conductors have opposite polarities; a phase busbar, adjacent to the DC link busbar, configured to electrically couple the plurality of switches to a stator of the electric motor; and a DC link connector, extending radially-outwardly away from the DC link busbar, configured to electrically couple the DC link busbar with bulk capacitance.

14. The bus bar assembly recited in claim 13, wherein the substrate is substantially circular.

15. The bus bar assembly recited in claim 13, wherein the DC electrical conductors include an electrically-conductive joint.