Busbar for vehicle and plug-in electric vehicle
By thickening the end section of the busbar, the overheating problem at the connection between the charging line and the charging pin is solved, achieving more efficient charging performance and safety.
Patent Information
- Application Number
- CN202480045913.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-07-21
- Filing Date
- 2024-06-21
- Publication Date
- 2026-02-03
AI Technical Summary
During the fast charging process of electric vehicles, the contact resistance at the connection between the charging line and the charging pin causes overheating, which limits the increase in charging power.
Design a bus that has a tapered end section in a flat side top view and is thickened in this area to form a hole for connection with a charging pin, reducing contact resistance and heat generation.
The thickened end section reduces contact resistance, decreases heat generation at the connection between the charging line and the charging pin, and improves the safety and charging efficiency of the charging system.
Smart Images
Figure CN121464548A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a busbar having a rectangular cross-section and a tapered end section in a top view of a flat side, wherein an opening is provided in the end section. The invention also relates to a plug-in electric vehicle including a charging port having at least two contact elements configured for conducting charging current, wherein each contact element is fixed, in particular threaded, to the opening of a corresponding busbar. This invention is particularly advantageously applicable to plug-in electric vehicles equipped with a charging port for fast charging, particularly DC fast charging. Background Technology
[0002] Especially during high-power DC fast charging of electric vehicles, the charging port generates a significant amount of waste heat. Since the temperature at the connection point between the internal charging circuitry and the charging current contact plug (or the "charging pins" of the charging port) must not exceed 90 degrees Celsius, the charging power is often reduced prematurely. Even if the charging pole (charging gun) has a cooling function, the internal charging circuitry of the electric vehicle is typically not cooled.
[0003] Charging circuits typically consist of copper cables (stranded wires) connected to plug connectors via clamping or soldering. These connectors are then attached to charging pins. High contact resistance occurs at these connection points, which can lead to excessive heat generation. Summary of the Invention
[0004] The purpose of this invention is to at least partially overcome the shortcomings of the prior art and, in particular, to provide a simple and low-cost implementation method to reduce heat generation in the area near the charging current contact plug in the charging current path of an electric vehicle.
[0005] This objective is achieved through the features of the independent claim. Preferred embodiments can be derived, in particular, from the dependent claims.
[0006] This objective is achieved by a bus having a rectangular cross-section and a tapered end section in a top view of a flat side, wherein an aperture is provided in the end section, and wherein the thickness of the end section is greater than the thickness of the non-tapered section preceding the end section.
[0007] The thickening of the bus at the tapered region on the flat side offsets the reduction in cross-section caused by the tapering. This, in turn, keeps the resistance low in the area of the hole in the bus that connects to the charging pin, thus reducing heat generation in that area. Furthermore, this increases the inner surface area of the hole, which reduces the contact resistance between the charging pin and the bus, similarly reducing heat generation.
[0008] The hole is used for connecting, in particular for directly threading, a charging pin.
[0009] A busbar should be understood in particular as a rigid or only slightly flexible, optionally malleably bendable conductive line made of metal. The metal may be, for example, copper or aluminum. A busbar having a rectangular cross-section may include a cross-section having two opposing shorter (“cross-section”) length sides and two opposing longer (“cross-section”) length sides. The shorter cross-section length sides may, for example, be isosceles inclined to each other, parallelogram-shaped inclined sides, or rectangular perpendicular to the longer cross-section length sides. Furthermore, the shorter cross-section length sides may also be curved, for example, mirror-symmetric. The “longer cross-section length” may also be referred to as the width of the busbar, and the vertical distance between them is referred to as the thickness of the busbar. In the case of a rectangular cross-section shape, the thickness specifically corresponds to the “shorter cross-section length”.
[0010] The longer cross-sectional length of the side forms a flat side of the busbar when viewed from above. The busbar has a tapered end section when viewed from above the flat side, and particularly includes: a non-tapered section with a constant width, which transitions at at least one end in the longitudinal extension direction of the busbar to a tapered section (“end section”) with a particularly continuously decreasing width.
[0011] In the non-tapered sections, the busbars are particularly profiled, with a constant width and thickness. They can be straight and / or curved in this region. The thickness of the end sections is greater than the thickness of the preceding non-tapered sections, particularly including: the end sections are thickened at least in a portion of the area, especially at least circumferentially around the hole, and particularly entirely or completely thickened.
[0012] One implementation involves maintaining at least approximately a constant value for the cross-sectional area of the end section along its longitudinal extension direction, or for its cross-sectional dimensions along its longitudinal extension direction. The advantage of this is that the ohmic resistance of the charging current in the end section does not change or only changes slightly.
[0013] One implementation involves the thickness of the end section varying at least approximately inversely with respect to the degree of taper relative to its longitudinal position. That is, if the width of the end section at a certain position along its longitudinal extension is reduced by a factor f (0 < f < 1) compared to the non-tapered section, then the thickness at that position is increased by a factor 1 / f compared to the non-tapered section.
[0014] One improvement is that the thickness of the end segment at at least one location, particularly in a sub-segment of the end segment, is at least 25% to 100% greater than the thickness of the preceding non-tapered segment. It has proven particularly advantageous in practice that the thickness of the end segment at at least one location, particularly in a sub-segment of the end segment, is at least 50% to 100% greater than the thickness of the preceding non-tapered segment.
[0015] One implementation involves maintaining a constant thickness of the end section within at least one sub-section of the end section. This is particularly easy to implement. An improvement is that the thickness of the end section around the hole remains constant, or rather, is constant. This advantageously facilitates planar mounting of contact elements (e.g., nuts) in the area surrounding the hole.
[0016] One implementation is that the end segments are substantially continuously tapering end segments (in the direction of their ends). This advantageously facilitates the design of thickened structures to ensure that the ohmic resistance does not undergo a practical abrupt change in the longitudinal direction, and in particular, remains at least approximately the same in the ohmic resistance.
[0017] For example, this implementation can be achieved particularly simply by having the first side edge of the busbar (when viewed from above) continue at least substantially straight from the end section, while the opposite second side edge extends obliquely, in particular straight, toward the first side edge from the end section, and in particular does not intersect with the first side edge.
[0018] One embodiment involves the end section being manufactured by locking a semi-finished product, which, when viewed from above, is shaped like a busbar and has a constant thickness, onto a flat side surface to a workpiece material that provides greater thickness in the end section region. This is particularly advantageous in manufacturing because the busbar itself, as a semi-finished product, does not need to undergo forming to achieve the greater thickness. The material locking connection can be achieved, for example, by pressing, friction welding, etc. Alternatively, the busbar, as a semi-finished product, can be thickened in the future end section by forming, for example, by pressing, hammering, etc. Advantageously, the holes are machined after the thickening.
[0019] In one embodiment, the busbar is made of aluminum. Aluminum is advantageously lightweight and inexpensive.
[0020] This objective is also achieved by an electric vehicle having at least one busbar as described above. The electric vehicle can be constructed accordingly to the busbar, or vice versa, and has the same advantages.
[0021] In one embodiment, the electric vehicle is a plug-in electric vehicle, which includes a charging port having at least two contact elements configured for conducting charging current, wherein each contact element is fixed, in particular threaded, to a hole in a corresponding busbar as described above. The plug-in electric vehicle can be a plug-in hybrid electric vehicle (PHEV) or a pure electric vehicle (PBEV).
[0022] One improvement is that the plug-in electric vehicle is configured for DC fast charging (so-called "DC charging").
[0023] The bus is particularly used to conduct charging current for charging or discharging between the drive battery of a plug-in electric vehicle and the corresponding charging pin.
[0024] The charging port may also optionally have additional contact elements, particularly contact pins, for example, for data communication.
[0025] One implementation involves at least two such buses being layered together in an electrically insulating manner. This facilitates mounting on two charging pins, which can be assigned to either a positive or negative terminal, for example. Alternatively, the buses can be separated by electrically insulating layers and stacked in a planar manner.
[0026] One implementation involves stacking two such busbars in a mirror-symmetrical arrangement, such that their orifices are side-by-side and exposed when viewed from above. This further facilitates installation. The exposed orifice arrangement specifically means that the orifice of one busbar will not be covered by the orifice of the other busbar. Attached Figure Description
[0027] The above-described features, characteristics, and advantages of the present invention, as well as the ways in which they are implemented, will become clearer and more readily understood in the following illustrative description of embodiments in conjunction with the accompanying drawings.
[0028] Figure 1 The busbar wiring of the vehicle according to the present invention is shown in a top view;
[0029] Figure 2 A longitudinal sectional view of the side view is shown. Figure 1 The bus line according to the present invention;
[0030] Figure 3 It shows Figure 1 The cross-section of the non-thickened section of the busbar in the busbar line; and
[0031] Figure 4 It shows Figure 1 The cross-section of the thickened section of the busbar in the busbar line. Detailed Implementation
[0032] Figure 1 A top view shows the bus line 1 of a vehicle F, particularly a plug-in electric vehicle, according to the present invention. Figure 2 The bus line 1 is shown in a longitudinal sectional view of the side view.
[0033] Bus line 1 has two buses 1A and 1B, which are arranged in a mirror-symmetrical stacked or overlapping manner along their common longitudinal extension direction L and are separated from each other by an electrical insulation layer 2. This can also be described as two buses 1A and 1B arranged in a mirror-symmetrical manner in a top view, electrically insulated from each other and layered together. In particular, the two buses 1A and 1B may have the same shape, but are arranged only in a mirror manner. In this embodiment, bus 1A is arranged above bus 1B in the top view. These two buses 1A and 1B may be made of copper or aluminum, for example, and electrically connect, for example, the charging pins (not shown) of the charging port to the vehicle's drive battery (not shown).
[0034] like Figure 3 As shown, the busbar 1A has a rectangular cross-section in its profile-shaped non-tapered section 1A-1, and has two relatively shorter sides SK and two relatively longer sides SL. The length of side SK corresponds to the thickness d of section 1A-1, and the length of side SL corresponds to the width b of section 1A-1. The area Q of the cross-section is calculated as Q = b · d.
[0035] The non-tapered section 1A-1 transitions toward at least one end to an end section 1A-2 that tapers continuously in the top view, wherein an opening 3 is provided. The openings 3 are arranged side by side in the top view and are each exposed.
[0036] The term "tapering" should be understood here as meaning that the width b' of busbar 1A in end section 1A-2 decreases as the distance to the end decreases. In this embodiment, the taper is achieved in such a way that the first side edge R1 of busbar 1A (shown here as the upper side edge) continues to extend in a straight line or parallel to the longitudinal extension direction L from end section 1A-2 at least substantially (here: except for the rounded portion on the end side), while the second side edge R2 (shown here as the lower side edge) extends in a straight, oblique line towards the first side edge R1 from the end section, and in particular, does not intersect with the first side edge R1.
[0037] like Figure 4 As shown, the thickness d' of end segment 1A-2 is greater than the thickness of segment 1A-1. Therefore, d' > d and b > b'. In this embodiment, the thickness d' first increases linearly, for example, making Q' = b' · d' ≈ b · d = Q. Subsequently, the thickness d' of end segment 1A-2 remains constant before reaching hole 3.
[0038] End section 1A-2 can be manufactured, for example, by materially locking a semi-finished product 4, which is shaped like a busbar in top view and has a constant thickness d, to a workpiece 5, which has a greater thickness d' in the region of end section 1A-2. For example, workpiece 5 can be fixed to semi-finished product 4 by friction welding.
[0039] Busbar 1B can be constructed similarly, and in particular identically.
[0040] Of course, the present invention is not limited to the embodiments shown.
[0041] Generally, "a" or "an" can be understood as singular or plural, especially in the sense of "at least one" or "one or more," unless explicitly excluded, for example, by expressions such as "exactly one."
[0042] In addition, numerical descriptions can refer to exact values or include general tolerance ranges, unless explicitly excluded.
[0043] List of reference numerals in the attached diagram:
[0044] 1 bus line
[0045] 1A bus
[0046] Non-recessed section of bus 1A-1
[0047] The tapering section of busbar 1A-2
[0048] 1B Bus
[0049] 2 insulation layers
[0050] 3 holes
[0051] 4 Semi-finished products
[0052] 5 workpieces
[0053] b. Width of the non-tapered section
[0054] b' Width of the tapering section
[0055] d Thickness of the non-gradient section
[0056] Thickness of the tapered section d'
[0057] F vehicle
[0058] R1 side edge
[0059] R2 side edge
[0060] SK shorter side length
[0061] SL has a longer side length.
Claims
1. A busbar (1A, 1B) having a rectangular cross section (Q, Q') and an end section (1A-2) tapering in a top view of a flat side, in which an aperture (3) is provided, wherein The thickness (d') of the end section (1A-2) is greater than the thickness of a non-tapered section (1A-1) preceding the end section (1A-2).
2. The busbar (1A, 1B) according to claim 1, wherein The area of the cross section (Q') of the end section (1A-2) at least approximately remains constant in at least one subsection along its longitudinal extension (L).
3. The busbar (1A, 1B) according to claim 2, wherein The thickness (d') in the end section (1A-2) at least approximately varies inversely proportional to the degree of tapering with respect to the longitudinal position.
4. The busbar (1A, 1B) according to claim 1, wherein The thickness (d') of the end section (1A-2) remains constant within at least one subsection of the end section (1A-2).
5. The busbar (1A, 1B) according to any one of the preceding claims, wherein The end section (1A-2) is a continuously tapering end section (1A-2).
6. The busbar (1A, 1B) according to claim 5, wherein The first side edge (R1) of the busbar (1A, 1B) continues at least substantially straight from the end section (1A-2), while the second side edge (R2) extends obliquely, in particular linearly, from the end section (1A-2) towards the first side edge (R1), in particular without intersecting the first side edge (R1).
7. The busbar (1A, 1B) according to any one of the preceding claims, wherein The end section (1A-2) is produced by materially locking a semi-finished product (4) having the shape of the busbar (1A, 1B) in a top view and a constant thickness (d) on a flat side to a workpiece (5) providing a greater thickness (d') in the region of the end section (1A-2).
8. Busbar (1A, 1B) according to any one of the preceding claims, characterized in that The busbar (1A, 1B) is made of aluminum.
9. A plug-in electric vehicle (F) comprising a charging port, the charging port having at least two contact elements arranged for conducting a charging current, wherein Each of the contact elements is fixed, in particular screwed, at a hole (3) of the respective busbar (1A, 1B) according to any of the preceding claims.
10. The plug-in electric vehicle (F) according to claim 9, wherein, At least two such busbars (1A, 1B) are combined in a layer-like manner with electrical insulation from one another.
11. The plug-in electric vehicle (F) according to claim 10, wherein Two busbars (1A, 1B) are arranged mirror-symmetrically on top of one another such that their holes (3) are arranged side by side and respectively exposed in a top view. The busbar (1A, 1B) is made of aluminum. Each of the contact elements is fixed, in particular screwed, at a hole (3) of the respective busbar (1A, 1B) according to any of the preceding claims. At least two such busbars (1A, 1B) are combined in a layer-like manner with electrical insulation from one another. Two busbars (1A, 1B) are arranged mirror-symmetrically on top of one another such that their holes (3) are arranged side by side and respectively exposed in a top view.