Modularized electric vehicle pre-charging circuit assembly

Abstract

The utility model discloses a modularized pre-charging circuit assembly of an electric automobile. The modularized pre-charging circuit assembly comprises a semiconductor switch which is packaged in a flat standard mode and a pre-charging resistor which is packaged in a flat mode. The pre-charging circuit assembly is electrically connected with the main positive loop through wires and pins on the PCBA board. According to the utility model, the pre-charging circuit assembly is independently produced, so that when the arrangement space of the BDU is insufficient, the pre-charging circuit assembly can be independently arranged and is connected with the main positive loop only through a small number of thinner non-power connecting wire harnesses; the problems of weight and cost rise caused by increase of the use amount of long copper bars due to separate arrangement of high-power loops in the prior art I are avoided; meanwhile, due to the standardized design of the pre-charging circuit assembly, the development and material cost can be reduced, and the problems of high mold cost and long mold opening period caused by customized non-standard special-shaped parts in the prior art II are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of on-off devices for electric vehicle battery packs, in particular to a modular electric vehicle pre-charging circuit component. Background Art

[0002] The high-voltage on-off device applicable to the battery pack of electric vehicles is also called the BDU module. Because the battery pack of electric vehicles has a relatively high DC voltage, and the drive motor or other electrical appliances of electric vehicles have a relatively large capacitance, when the vehicle switches from the "power-off" state to the "power-on" state, that is, the moment when the battery pack is connected to the external electrical appliances, it is equivalent to the voltage source being short-circuited through the capacitor, and there will be a large impact current, which has a great negative impact on the main positive relay contacts that are finally closed, and may even cause the contacts to stick. Therefore, a pre-charging circuit or a slow-start circuit is usually set up to mitigate this impact, and the relays, pre-charging resistors and other devices and circuits required for the pre-charging circuit are usually integrated in the main positive circuit of the BDU module, see Figure 1 shown.

[0003] With the development of technology and consumers' demand for longer pure electric driving range of electric vehicles, the current power battery system design is moving towards higher space utilization. This means that as many batteries as possible should be installed in the battery pack, which seriously compresses the layout space of other components, and the space left for electrical components such as BDU is becoming increasingly narrow and irregular. The traditional "box" BDU is difficult to arrange.

[0004] In the prior art, two methods are generally used to solve the above problems, namely, split BDU and specially customized special-shaped BDU;

[0005] The split BDU of the prior art, that is, according to the location of the high-voltage interface of the whole vehicle and the available layout space of the battery pack, the original complete BDU is functionally split to realize that the BDU occupies two smaller spaces instead of one whole larger space.

[0006] See also Figure 2 As shown, for split-type BDU, because the pre-charging circuit is closely related to the main positive circuit, the two are usually not separated, but the relay or fuse of the main negative circuit or fast charging circuit is separated separately. Therefore, the main negative circuit or fast charging circuit is usually a high-power circuit, which has a high current requirement for the electrical connection copper busbar in the circuit. Therefore, this method cannot avoid long-distance high-power electrical connection, which will inevitably lead to the appearance of long copper busbars, and the increase in the amount of copper busbars is very unfavorable for the cost and weight control of the entire battery pack.

[0007] The specially customized special-shaped BDU of the prior art usually prioritizes the arrangement of battery modules that occupy more than 60% of the volume ratio in the battery pack, and the remaining "corner areas" where battery modules cannot be arranged are used to arrange other component modules such as thermal management inlet and outlet pipes, BMS or OBC / DCDC. Because the thermal management inlet and outlet pipes have related fixed models or sizes, the related circuits and layouts of other component modules such as BMS or OBC / DCDC basically have relatively fixed space requirements and are usually arranged as a whole. Therefore, the space left for BDU and its electrical components is more scattered and special-shaped.

[0008] See also Figure 3 As shown in the figure, the specially customized special-shaped BDU is difficult to develop and takes a long time. Secondly, due to the large number of special-shaped or customized parts, the related mold costs are high and the mold opening cycle is long, resulting in high costs. Only when the battery pack to which the BDU belongs has a huge shipment volume can the R&D and production costs be spread out through economies of scale.

[0009] Therefore, based on the above technical problems, technicians in this field urgently need to develop a modular electric vehicle pre-charging circuit component. Utility Model Content

[0010] The purpose of the utility model is to provide a modular electric vehicle pre-charging circuit component. The pre-charging circuit component of the present application is produced separately. When the BDU layout space is insufficient, the pre-charging circuit component can be arranged independently and connected to the main positive circuit only through a small amount of thinner non-power connection harness, thereby avoiding the weight and cost increase caused by the increase in the amount of long copper busbars caused by the separate arrangement of high-power circuits in the prior art one; at the same time, the standardized design of the pre-charging circuit component of the present application can reduce development and material costs, and avoid the problems of high mold cost and long mold opening cycle caused by the customized non-standard special-shaped parts in the prior art two.

[0011] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0012] The utility model discloses a modular electric vehicle pre-charging circuit assembly, which comprises:

[0013] Semiconductor switches in flat standard packages; and

[0014] Pre-charge resistor for flat package;

[0015] The pre-charging circuit assembly is electrically connected to the main positive circuit through the wiring and pins on the PCBA board.

[0016] Further, the pre-charging circuit assembly comprises:

[0017] A heat dissipation fin, the heat dissipation fin having a heat dissipation plate body and a plurality of fins formed on the heat dissipation plate body; and

[0018] Assemble and fix the PCBA board on the upper end of the heat dissipation fin;

[0019] Two mounting areas are symmetrically arranged on one side of the heat sink body, and the semiconductor switch and the pre-charging resistor are respectively fixed in the corresponding mounting areas;

[0020] Four heat dissipation mounting screws are arranged at the edge of the heat dissipation plate body so as to be assembled and fixed with the corresponding positions of the battery pack through the four heat dissipation mounting screws.

[0021] Furthermore, the PCBA board is welded with a semiconductor switch drive control cable and a main positive circuit cable.

[0022] As the first integrated structure of the pre-charging circuit assembly of the present application, the pre-charging circuit assembly is arranged at the corner gap of the battery pack;

[0023] The side wall of the battery pack is prefabricated with an internal thread column, and the pre-charging circuit assembly is assembled and fixed to the internal thread column with the side wall of the battery pack through heat dissipation mounting screws.

[0024] As a second integrated structure of the pre-charging circuit assembly of the present application, the pre-charging circuit assembly is arranged in the remaining space on the longitudinal beam or the cross beam of the battery pack;

[0025] A bracket for mounting the pre-charging circuit assembly is provided on the longitudinal beam or the cross beam of the battery pack;

[0026] The pre-charging circuit assembly is assembled and fixed to the bracket via heat dissipation mounting screws.

[0027] As a third integrated structure of the pre-charging circuit assembly of the present application, the pre-charging circuit assembly is assembled and fixed on the inner wall of the battery pack or above the liquid cooling plate.

[0028] Furthermore, when the pre-charging circuit assembly is assembled and fixed above the liquid cooling plate, the heat sink body of the heat dissipation fin has the fin on the side away from the liquid cooling plate.

[0029] In the above technical solution, the utility model provides a modular electric vehicle pre-charging circuit assembly, which has the following beneficial effects:

[0030] The pre-charging circuit assembly of the utility model is produced separately. When the BDU layout space is insufficient, the pre-charging circuit assembly can be arranged independently and connected to the main positive circuit only by a small amount of thinner non-power connection harness, thereby avoiding the weight and cost increase caused by the increase in the amount of long copper busbars due to the separate arrangement of high-power circuits in the prior art one; at the same time, the standardized design of the pre-charging circuit assembly of the present application can reduce development and material costs, and avoid the problems of high mold cost and long mold opening cycle caused by the customized non-standard special-shaped parts in the prior art two. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present utility model. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0032] Figure 1 It is a circuit schematic diagram of a pre-charging circuit component in the prior art;

[0033] Figure 2 A circuit schematic diagram of a pre-charging circuit assembly of prior art 1;

[0034] Figure 3 It is a structural schematic diagram of a special-shaped BDU device of the second prior art;

[0035] Figure 4 A circuit schematic diagram of a modular electric vehicle pre-charging circuit assembly disclosed in an embodiment of the present application;

[0036] Figure 5 A schematic diagram of a modular electric vehicle pre-charging circuit assembly disclosed in an embodiment of the present application Figure 1 ;

[0037] Figure 6 A schematic diagram of a modular electric vehicle pre-charging circuit assembly disclosed in an embodiment of the present application Figure 2 ;

[0038] Figure 7 An exploded view of the structure of a modular electric vehicle pre-charging circuit assembly disclosed in an embodiment of the present application;

[0039] Figure 8 This is a schematic structural diagram of a pre-charging circuit assembly integrated into a corner gap of a battery pack in a first embodiment of a modular electric vehicle pre-charging circuit assembly disclosed in an embodiment of the present application;

[0040] Fig. 9This is a schematic structural diagram of a pre-charging circuit assembly integrated into a longitudinal beam of a battery pack in a second embodiment of a modular electric vehicle pre-charging circuit assembly disclosed in an embodiment of the present application;

[0041] Fig.10 This is a structural schematic diagram of a pre-charging circuit assembly integrated into a battery pack side wall or a liquid cooling plate in Example 3 of a modular electric vehicle pre-charging circuit assembly disclosed in an embodiment of the present application.

[0042] Description of reference numerals:

[0043] 10. Pre-charging circuit assembly; 20. Main positive circuit; 30. Battery pack;

[0044] 1. Heat sink; 2. PCBA board; 3. Semiconductor switch; 4. Pre-charge resistor;

[0045] 101. fin; 102. heat dissipation mounting screw;

[0046] 201, semiconductor switch drive control cable; 202, main positive circuit cable; 203, PCBA mounting screws;

[0047] 31. Gaps at edges and corners; 32. Longitudinal beams; 33. Longitudinal beam brackets; 34. Battery pack side walls or liquid cooling plates. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings.

[0049] See also Figures 4 to 10 As shown;

[0050] This embodiment discloses a modular electric vehicle pre-charging circuit assembly, the pre-charging circuit assembly 10 comprising:

[0051] A semiconductor switch 3 in a flat standard package; and

[0052] Pre-charge resistor 4 in flat package;

[0053] The pre-charging circuit assembly 10 is electrically connected to the main positive circuit 20 through the wiring and pins on the PCBA board 2 .

[0054] The pre-charging circuit assembly 10 based on the semiconductor switch 3 of the flat standard package and the pre-charging resistor 4 of the flat package as main components specifically includes:

[0055] A heat dissipation fin 1, wherein the heat dissipation fin 1 comprises a heat dissipation plate body and a plurality of fins 101 formed on the heat dissipation plate body; and

[0056] Assemble the PCBA board 2 fixed to the upper end of the heat dissipation fin 1;

[0057] Two mounting areas are symmetrically arranged on one side of the heat sink body, and the semiconductor switch 3 and the pre-charging resistor 4 are respectively fixed in the corresponding mounting areas;

[0058] Four heat dissipation mounting screws 102 are arranged at the edge of the heat dissipation plate body, so as to be assembled and fixed with the corresponding positions of the battery pack 30 by the four heat dissipation mounting screws 102 .

[0059] Specifically, the pre-charging circuit assembly 10 of the present embodiment replaces the pre-charging relay from the traditional electromagnetic force driven mechanical contact type to a semiconductor switch 3 such as a MOS tube, solid-state relay, circuit breaker, etc. in a flat standard package, and replaces the pre-charging resistor 4 from the traditional cement resistor, aluminum shell resistor, etc. to a power resistor, thick film resistor, etc. in a flat package, and replaces the electrical connection between the two from the traditional copper, aluminum bus or wiring harness screw connection to the routing and pin welding on the PCBA board 2, and then combines the flattened design of the heat dissipation fin 1, so as to achieve a significant reduction in the volume of the two devices, and ultimately achieve the flattening and miniaturization of the pre-charging circuit assembly 10.

[0060] Preferably, the PCBA board 2 of this embodiment is welded with a semiconductor switch drive control cable 201 and a main positive circuit cable 202 .

[0061] Since the MOS tube, power resistor and other devices of this embodiment have different rated parameters and specifications, the heat dissipation power of the flattened heat sink 1 mentioned above in this application can also be flexibly adjusted. These designs of this embodiment can be integrated together to be suitable for different vehicle conditions. The rated specifications of the devices and the heat sink power can be flexibly adjusted according to the voltage, X capacitance, pre-charge time, pre-charge number, pre-charge interval and other requirements of the vehicle.

[0062] See also Figure 8 As shown, as the first integrated structure of the pre-charging circuit assembly 10 of the present application, the pre-charging circuit assembly 10 of the first embodiment is arranged at the corner gap 31 of the battery pack 30;

[0063] Specifically, first, an internal thread column is prefabricated on the side wall of the battery pack 30 , and the pre-charging circuit assembly 10 is assembled and fixed to the internal thread column with the side wall of the battery pack 30 by means of heat dissipation mounting screws 102 .

[0064] In the first embodiment of the present invention, the pre-charging circuit assembly 10 is integrated into the corner gap 31 of the battery pack 30. In order to achieve assembly, an internal threaded column is prefabricated on the side wall of the battery pack 30. Due to the flat and miniaturized design of the pre-charging circuit assembly 10, the installation requirements of the corner gap 31 can be fully met.

[0065] See also Fig. 9As shown, as the second integrated structure of the pre-charging circuit assembly 10 of the present application, the pre-charging circuit assembly 10 of the second embodiment is arranged in the remaining space above the longitudinal beam 32 or the cross beam of the battery pack 30;

[0066] A bracket for mounting the pre-charging circuit assembly 10 is provided on the longitudinal beam 32 or the cross beam of the battery pack 30;

[0067] The pre-charging circuit assembly 10 is assembled and fixed to the bracket by heat dissipation mounting screws 102 .

[0068] See also Fig. 9 The structure shown, Fig. 9 Taking the pre-charging circuit assembly 10 of the present application integrated in the longitudinal beam bracket 33 of the longitudinal beam 32 of the battery pack 30 as an example, the corresponding position of the pre-charging circuit assembly 10 integrated in the longitudinal beam 32 or the cross beam of the battery pack 30 is further explained and illustrated.

[0069] See also Fig.10 As shown, as the third integrated structure of the pre-charging circuit assembly 10 of the present application, the pre-charging circuit assembly 10 of the third embodiment is assembled and fixed on the inner wall of the battery pack or above the liquid cooling plate 34.

[0070] Since an external cold source is introduced, when the pre-charging circuit assembly 10 of the third embodiment is assembled and fixed on the liquid cooling plate, the heat sink body of the heat sink 1 has fins 101 on the side away from the liquid cooling plate. This design can further reduce the volume of the heat sink 1.

[0071] In the above technical solution, the utility model provides a modular electric vehicle pre-charging circuit assembly, which has the following beneficial effects:

[0072] The pre-charging circuit assembly 10 of the utility model is produced separately. When the BDU layout space is insufficient, the pre-charging circuit assembly 10 can be arranged independently, and is only connected to the main positive circuit 20 through a small amount of thinner non-power connection harnesses, thereby avoiding the weight and cost increase caused by the increase in the amount of long copper bars caused by the separate arrangement of high-power circuits in the prior art one; at the same time, the standardized design of the pre-charging circuit assembly 10 of the present application can reduce development and material costs, and avoid the problems of high mold cost and long mold opening cycle caused by the customized non-standard special-shaped parts in the prior art two.

[0073] The flat design of the pre-charging circuit assembly 10 of the present invention can reduce the overall space occupied by the BDU device and save more layout space in the battery pack.

[0074] In addition, when the space left for the BDU in the battery pack is extremely narrow or irregular, the flat, modular pre-charging circuit assembly 10 can be independently arranged in a suitable space at a distance, and only connected to the main positive circuit 20 through a small number of thinner non-power connection harnesses, which greatly improves the flexibility of the BDU design while keeping costs under control.

[0075] Finally, the standardized and modular design of the pre-charging circuit assembly 10 can reduce development and material costs, and achieve rapid development and rapid matching.

[0076] The above only describes some exemplary embodiments of the present invention by way of illustration. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A modular electric vehicle pre-charging circuit assembly, characterized in that: The pre-charging circuit assembly (10) comprises: A semiconductor switch (3) in a flat standard package; and Pre-charge resistor for flat package (4); The pre-charging circuit component (10) is electrically connected to the main positive circuit (20) through wiring and pins on the PCBA board (2).

2. A modular electric vehicle pre-charging circuit assembly according to claim 1, characterized in that: The pre-charging circuit assembly (10) comprises: A heat dissipation fin (1), the heat dissipation fin (1) comprising a heat dissipation plate body and a plurality of fins (101) formed on the heat dissipation plate body; and A PCBA board (2) is assembled and fixed to the upper end of the heat dissipation fin (1); Two installation areas are symmetrically arranged on one side of the heat sink body, and the semiconductor switch (3) and the pre-charging resistor (4) are respectively fixed in the corresponding installation areas; Four heat dissipation mounting screws (102) are arranged at the edge of the heat dissipation plate body so as to be assembled and fixed to corresponding positions of the battery pack (30) through the four heat dissipation mounting screws (102).

3. A modular electric vehicle pre-charging circuit assembly according to claim 2, characterized in that, The PCBA board (2) is welded with a semiconductor switch drive control cable (201) and a main positive circuit cable (202).

4. A modular electric vehicle pre-charging circuit assembly according to any one of claims 1 to 3, characterized in that: The pre-charging circuit assembly (10) is arranged at a corner gap (31) of the battery pack (30); The side wall of the battery pack (30) is prefabricated with an internal thread column, and the pre-charging circuit assembly (10) is assembled and fixed to the internal thread column with the side wall of the battery pack (30) via heat dissipation mounting screws (102).

5. A modular electric vehicle pre-charging circuit assembly according to any one of claims 1 to 3, characterized in that: The pre-charging circuit assembly (10) is arranged in the remaining space above the longitudinal beam (32) or the cross beam of the battery pack (30); A bracket for mounting the pre-charging circuit assembly (10) is provided on the longitudinal beam (32) or the transverse beam of the battery pack (30); The pre-charging circuit assembly (10) is assembled and fixed to the bracket via heat dissipation mounting screws (102).

6. A modular electric vehicle pre-charging circuit assembly according to claim 2, characterized in that: The pre-charging circuit assembly (10) is assembled and fixed on the inner wall of the battery pack or above the liquid cooling plate (34).

7. A modular electric vehicle pre-charging circuit assembly according to claim 6, characterized in that: When the pre-charging circuit assembly (10) is assembled and fixed above the liquid cooling plate, the heat sink body of the heat sink (1) has the fin (101) on the side away from the liquid cooling plate.

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