CN217145669U

CN217145669U - Cooling flow channel structure of multiplexing metal-based circuit board and vehicle-mounted charger

Info

Publication number: CN217145669U
Application number: CN202220140873.2U
Authority: CN
Inventors: 冯颖盈; 姚顺; 徐金柱; 罗耀文; 张远昭; 王虎
Original assignee: Shenzhen Vmax Power Co Ltd
Current assignee: Shenzhen Vmax Power Co Ltd
Priority date: 2022-01-19
Filing date: 2022-01-19
Publication date: 2022-08-09
Anticipated expiration: 2032-01-19

Abstract

The utility model discloses a cooling flow channel structure and on-vehicle machine that charges of multiplexing metal-based circuit board, cooling flow channel structure includes: the cooling device comprises a machine shell (1), a flow channel body (2) arranged on the machine shell and a cooling flow channel (3) arranged in the flow channel body, wherein at least one side of the side wall of the flow channel body is provided with a hollow window, the hollow window is blocked by a heat dissipation surface of a metal base circuit board (4), one side of the metal base circuit board with an electronic element (5) deviates from the hollow window, and a sealing device is arranged between the heat dissipation surface of the metal base circuit board and the edge of the hollow window; the utility model discloses multiplexing metal base circuit board has effectively promoted the space utilization of cooling runner as cooling runner's partly, combines the stronger heat conductivility of metal base circuit board and compact face volume, has guaranteed improvement when signal transmission, whole power density to power device's radiating efficiency and whole space utilization, is favorable to on-vehicle machine that charges and surpasss the whole integration, miniaturization and the lightweight of filling the liquid cooling module.

Description

Cooling flow channel structure of multiplexing metal-based circuit board and vehicle-mounted charger

Technical Field

The utility model relates to a power electronic technology field, concretely relates to cooling runner structure and on-vehicle machine that charges of multiplexing metal-based circuit board.

Background

With the development of electronic technology, electronic devices are increasingly widely used, and meanwhile, the power density of the electronic devices is continuously improved, and the heating power is increased. Therefore, the heat dissipation problem has become a major bottleneck restricting the further development of electronic technology. A great deal of practice shows that: temperature is one of the main causes of electronic device failure, and as temperature increases, the probability of device failure increases exponentially. Electronic devices need to operate at near full load for long periods of time, and under limited conditions, solving the heat dissipation problem of such electronic devices presents a significant challenge. In the application fields such as electric vehicles, for example, the environmental temperature of a motor controller, a vehicle-mounted charger and a charging module is very high, and since functional elements such as an IGBT, an MOS transistor and a capacitor are included in the parts, the parts are very sensitive to the temperature, and particularly in a high-temperature environment, the performance of the parts is slightly affected, and accidents such as explosion are generated.

At present, most of high-power conversion devices used in a power transmission system of a vehicle-mounted charger are of plug-in type, the power devices are directly attached to a metal-based circuit board (an aluminum substrate or a copper substrate), and then the metal-based circuit board is fixed on a planar (parallel to a horizontal plane) cooling flow channel. The traditional planarization cooling flow channel is adopted to dissipate heat of the power device, the metal base circuit board, the cooling flow channel and the cooling flow channel cover plate are all arranged in parallel with the horizontal plane, so that the plane and space utilization rate of the cooling flow channel heat dissipation structure is low, meanwhile, a large number of power switching interfaces on the traditional metal base circuit board occupy a large amount of area on the metal base circuit board, and the effective area and utilization rate of the metal base circuit board for heat dissipation are low.

Fig. 1 shows a schematic diagram of a conventional metal-based circuit board bonded to a cooling channel, and a combined body thereof includes an electronic component 5, a copper foil layer 4a, an insulating layer 4b, a metal substrate 4c, a heat-conducting silicone layer 4d, a channel body 2 side wall, and a cooling channel 3 stacked in this order. Therefore, the heat dissipation structure of the power device of the traditional planarization cooling flow channel and the vehicle-mounted charger have low overall space utilization rate of the structure, and are not beneficial to the improvement of power density and the requirement of product integration miniaturization.

Therefore, how to design a miniaturized, high-density heat dissipation cooling channel is an urgent technical problem to be solved in the industry.

SUMMERY OF THE UTILITY MODEL

In order to solve the above-mentioned defect that exists among the prior art, the utility model provides a cooling flow channel structure and on-vehicle machine that charges of multiplexing metal base circuit board.

The utility model discloses a technical scheme design a cooling flow channel structure of multiplexing metal-based circuit board, include: the cooling flow channel comprises a machine shell, a flow channel body arranged on the machine shell and a cooling flow channel arranged in the flow channel body, wherein at least one side of the side wall of the flow channel body is provided with a hollowed-out window, the hollowed-out window is blocked by a heat dissipation surface of a metal-based circuit board, one side of the metal-based circuit board with an electronic element deviates from the hollowed-out window, and a sealing device is arranged between the heat dissipation surface of the metal-based circuit board and the edge of the hollowed-out window.

The metal-based circuit board comprises an electronic element, a copper foil layer, an insulating layer and a metal substrate which are sequentially stacked, and the outer side face of the metal substrate is the heat dissipation face.

And a plurality of corrugated grooves are arranged on the heat dissipation surface of the metal base circuit board, and the directions of the corrugated grooves are vertical to the direction of water flow in the cooling flow channel.

The edge of the metal base circuit board is provided with a through hole, the edge of the hollowed-out window is provided with a screw hole, and a screw penetrates through the through hole to be in threaded connection with the screw hole, so that the hollowed-out window is blocked by the metal base circuit board.

The screw penetrates through the insulating sleeve and then is inserted into the through hole, and the nut of the screw is sunk into the groove of the insulating sleeve.

And a turbulence generator is arranged on the inner side wall of the cooling flow passage.

The cooling flow channel is in a strip shape and is bent into a U-shaped arrangement, a water inlet and a water outlet are respectively arranged at two ends of the cooling flow channel, the longitudinal section of the cooling flow channel is in an open deep groove shape, and a cooling flow channel cover plate is arranged at the opening of the cooling flow channel.

The metal-based circuit board is arranged on the outward side wall of the U-shaped cooling flow channel, and a heating element can be arranged in the middle of the bend of the U-shaped cooling flow channel.

An insulating frame is arranged between the metal base circuit board and the hollow window, the insulating frame adopts a window frame structure, and the cross section of the insulating frame is L-shaped; the metal base circuit board is placed in the insulating frame, the periphery of the metal base circuit board is an insulating frame side wall, and an insulating frame bottom wall is arranged between the metal base circuit board and the hollow window.

And a layer of pouring sealant is poured on one surface of the metal-based circuit board with the electronic element, and an insulating plate is covered on the outer surface of the pouring sealant.

The sealing device adopts a sealing rubber ring, and the metal-based circuit board adopts an aluminum-based circuit board.

The utility model also designs an on-vehicle machine that charges, including charging circuit and cooling system, cooling system adopts the cooling flow channel structure of foretell multiplexing metal base circuit board.

The utility model provides a technical scheme's beneficial effect is:

the utility model discloses multiplexing metal base circuit board is as a part of cooling runner, and the cooling surface of base plate directly contacts with the coolant liquid in the cooling runner and carries out the heat transfer, has effectively promoted the space utilization of cooling runner, combines the stronger heat conductivility of metal base circuit board and compact face volume, has improved the radiating efficiency and the whole space utilization to power device when having guaranteed signal transmission, whole power density, is favorable to the whole integration, miniaturization and the lightweight of on-vehicle machine that charges and super liquid cooling module; the power device replaces a plug-in unit by patch mounting, so that the consistency of the power device is better; the pins are directly arranged on the top end face of the metal base circuit board to realize power transmission, so that the area of the working face of the metal base circuit board is saved, and the effective heat dissipation area of the metal base circuit board is utilized to the maximum extent.

Drawings

The invention is explained in more detail below with reference to exemplary embodiments and the accompanying drawings, in which:

FIG. 1 is a schematic diagram of a conventional metal-based circuit board bonded to a cooling channel;

FIG. 2 is a schematic view illustrating the principle of the combination of the metal-based circuit board and the cooling channel of the present invention;

FIG. 3 is a schematic diagram of the runner body separated from the metal-based circuit board;

FIG. 4 is a schematic view of a hollow window of the flow channel body;

FIG. 5 is a front view of a metal-based circuit board (with electronic components);

FIG. 6 is a back (heat sink) view of a metal-based circuit board;

FIG. 7 is an exploded view of the preferred embodiment;

FIG. 8 is a top view of the preferred embodiment;

FIG. 9 is a bottom view of the preferred embodiment;

FIG. 10 is a graph of thermal simulation data for internal dies of a power device using a prior art cooling flow channel structure;

FIG. 11 is a graph of external thermal simulation data for a power device using a prior art cooling flow channel structure;

fig. 12 is a graph of thermal simulation data of internal wafer of a power device using the cooling flow channel structure of the present invention;

FIG. 13 is a graph of the external thermal simulation data of the motor power device with the cooling flow channel structure according to the present invention;

FIG. 14 is a schematic perspective view of an insulating frame disposed between a metal-based circuit board and a hollow window;

FIG. 15 is a perspective view of the metal-based circuit board, the potting compound, and the insulating board.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention will be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The utility model discloses a cooling flow channel structure of multiplexing metal base circuit board, it includes: the cooling structure comprises a casing 1, a flow channel body 2 arranged on the casing and a cooling flow channel 3 arranged inside the flow channel body, wherein at least one side of the side wall of the flow channel body is provided with a hollowed-out window (see the schematic view of the hollowed-out window of the flow channel body shown in figure 4), the hollowed-out window is plugged by a heat dissipation surface of a metal base circuit board 4 (see the schematic view of the separation of the flow channel body and the metal base circuit board shown in figure 3), one side of the metal base circuit board with an electronic component 5 deviates from the hollowed-out window, and a sealing device is arranged between the heat dissipation surface of the metal base circuit board and the edge of the hollowed-out window.

Referring to the schematic diagram of the principle of combining the metal-based circuit board and the cooling flow channel shown in fig. 2, the metal-based circuit board of the present invention includes an electronic component 5, a copper foil layer 4a, an insulating layer 4b, and a metal substrate 4c stacked in sequence, and the outer side surface of the metal substrate 4c is the heat dissipation surface.

The utility model discloses in, dispel the heat as cooling runner 3's lateral wall and coolant liquid direct contact between metal substrate's the cooling surface. The heat dissipation effect is greatly improved.

Present heat radiation structure with the utility model discloses heat radiation structure's thermal resistance calculation data and radiating simulation data contrast as follows:

copper thermal conductivity:

solder heat conductivity coefficient:

aluminum-based aluminum base heat conduction systemNumber:

the heat conductivity coefficient of the shell is as follows:

thermal resistance of an insulating layer of the aluminum substrate:

thermal resistance of heat dissipation silicone grease:

TO263 copper base heat dissipation area: s _device ：＝7.74mm·8.59mm＝66.487mm ²

Thickness of soldering tin: TH _solder ：＝0.1mm

Thickness of copper foil of aluminum substrate: TH _copper ：＝0.105mm

Thickness of the aluminum substrate: TH _Al ：＝2mm

Thickness of the heat-conducting silicone grease: TH _Si ：＝0.1mm

The thickness of the water channel wall: TH _ALSi12Fe ：＝2mm

Thermal resistance of the device:

thermal resistance of a welding surface:

thermal resistance of copper foil:

aluminum substrate insulatorThermal insulation layer resistance:

aluminum-based thermal resistance of aluminum substrate:

thermal resistance of heat-conducting silicone grease:

thermal resistance of water channel wall:

total thermal resistance:

refer to the inside wafer thermal simulation data diagram of the use current cooling runner structure power device that is shown in fig. 10, the outside thermal simulation data diagram of the use current cooling runner structure power device that is shown in fig. 11, the use that is shown in fig. 12 the utility model discloses the inside wafer thermal simulation data diagram of cooling runner structure power device, the use that is shown in fig. 13 the utility model discloses cooling runner structure motor power device outside thermal simulation data diagram. Compare from four pictures and know, use the utility model discloses afterwards, the inside temperature of the inside wafer of power device descends about 46 degrees, and the apparent temperature of power device descends about 26 degrees, and the cooling is respond well.

Referring to the front view (with electronic component) of the metal-based circuit board shown in fig. 5, the metal-based circuit board includes a metal substrate, an electronic component 5 (mainly referred to as a power device MOS transistor), and a power signal connection terminal 15, a power device is reflow soldered on the metal substrate, and the power device replaces a plug-in component with a patch-mounting component, so that the consistency of the power device is better, and the power signal transmission is performed with the main PCB assembly 16 through the power signal terminal. Further, the top end of the metal substrate is provided with at least one plug port electrically connected with the power device, the PCB is provided with a slot hole allowing the plug port to be inserted, and a conductor used for being electrically connected with the plug port is arranged in the slot hole.

Referring to the view of the back surface (heat radiation surface) of the metal-base circuit board shown in fig. 6, a plurality of corrugated grooves 4e are formed in the heat radiation surface of the metal-base circuit board 4, and the directions of the corrugated grooves are perpendicular to the direction of the water flow in the cooling flow passage 3. The heat dissipation area of the corrugated groove is increased to the maximum extent, and the strength of the whole surface of the metal substrate can be further increased by the rib positions formed on the corrugated groove.

Referring to a schematic diagram of the flow channel body and the metal-based circuit board shown in fig. 3 and an exploded view of a preferred embodiment shown in fig. 7, a through hole 4f is formed in the edge of the metal-based circuit board 4, a screw hole 8 is formed in the edge of the hollow window, and a screw 7 penetrates through the through hole and is screwed with the screw hole, so that the metal-based circuit board 4 is blocked by the hollow window. In one embodiment shown in fig. 4, in order to conveniently arrange the screw hole 8 and avoid the screw hole 8 from becoming a through hole, a reinforcing rib 2a is arranged on the side of the runner body 2 away from the hollow window at the position where the screw hole 8 is arranged to increase the thickness of the runner body.

Referring to fig. 3 and 7, in the preferred embodiment, the screw 7 is inserted into the through hole 4f after passing through the insulating sleeve 9, and the nut of the screw 7 is sunk into the groove of the insulating sleeve 9. The three-dimensional structure of the insulating sleeve 9 is shown in fig. 3. Separate through an insulating cover between screw and the metal substrate, effectual increase metal substrate's utilization ratio like this, because power device pastes on metal substrate, the screw is with runner body 2 contacts, need guarantee certain ann rule distance between power device and the screw, and insulating cover can reduce this ann rule distance, increases metal substrate's effective utilization ratio. Further, the screw cap is contacted with the inner groove of the insulating sleeve, and the outer plane of the insulating sleeve is contacted with the functional surface (the surface for welding electronic elements) of the metal substrate, so that the insulation of the screw and the functional surface of the metal substrate is ensured. Further, the nut of the screw 7 is sunk into the groove of the insulating sleeve 9, thus increasing the creepage distance from the screw to the functional surface of the metal substrate.

Referring to fig. 4 and 7, the cooling flow channel 3 is provided with turbulence generators 10 on its inner side wall. The turbulence generator 10 is a wavy groove, when the cooling liquid flows in the water channel, part of the fluid flows into the groove, and the groove can form a plurality of small heat dissipation flow channels to take away the heat of the original device. Furthermore, a plurality of small heat dissipation flow channels are formed in the grooves, and the strength of the bottom of the three-dimensional water channel of the whole shell can be increased by the ribs formed between the grooves.

Referring to fig. 8, which shows a top view of the preferred embodiment, the cooling flow channel 3 is a strip bent into a U-shape and provided with an inlet 11 and an outlet 12 at its two ends. Referring to the bottom view of the preferred embodiment shown in fig. 9, the longitudinal section of the cooling flow channel 3 is in the form of an open deep groove, and a cooling flow channel cover plate 13 is provided at the opening of the cooling flow channel 3. The cooling flow channel cover plate 13 is sealed and fixed with the flow channel body 2 through friction stir welding. Furthermore, the flow channel body 2 is provided with a sunken profile-modeling (imitating the appearance of the cooling flow channel cover plate 13) groove to perform a positioning and limiting function on the cooling flow channel cover plate 13, so that the cooling flow channel cover plate 13 is placed in the groove, and the limitation and positioning of the cooling flow channel cover plate 13 can be met. The fixing and sealing method is not limited to friction stir welding, and sealing silicone rubber and screw fixing and sealing can also be adopted.

Referring to fig. 7, an exploded view of the preferred embodiment is shown; the metal base circuit board 4 is arranged on the outward side wall of the U-shaped cooling flow channel 3, and a heating element can be arranged in the bent inner middle part of the U-shaped cooling flow channel 3. When the utility model discloses when using in the on-vehicle machine that charges, heating element is magnetic element, and magnetic element places in the U style of calligraphy, and the magnetic element left and right sides all contacts with runner body 2, and magnetic element adopts heat conduction encapsulating to fill with runner body 2's clearance, and such the at utmost of arranging promotes magnetic element radiating effect, has improved magnetic core element's power of use to reduce power module's whole volume and promote power module's whole power density.

Referring to fig. 14, in the preferred embodiment, an insulating frame 20 is disposed between the metal-based circuit board 4 and the hollow window, and the insulating frame has a window frame structure with an L-shaped cross section; the metal base circuit board 4 is placed in the insulating frame, the periphery of the metal base circuit board is the side wall of the insulating frame, and the bottom wall of the insulating frame is arranged between the metal base circuit board and the hollow window. The insulation frame 20 is added, so that the insulation between the metal base circuit board and the hollow window can be increased on one hand, and the creepage distance and the electric clearance between the circuit on the upper surface of the metal base circuit board and the casing can be increased on the other hand.

Referring to fig. 15, a layer of potting compound 21 is poured on the side of the metal-based circuit board 4 with the electronic component 5. The pouring sealant can strengthen the integrity of the electronic device and improve the resistance to external impact and vibration; the insulation between internal elements and circuits is improved, and the miniaturization and the light weight of devices are facilitated; the direct exposure of elements and circuits is avoided, and the waterproof and moisture-proof performances of the device are improved.

Referring to fig. 15, a preferred embodiment is shown in which the exterior surface of the potting adhesive is covered with an insulating plate 22. This can further improve the insulating property of the metal base circuit board 4.

Referring to the preferred embodiment shown in fig. 7, the sealing means employs a sealing rubber ring 6. And a sealing rubber ring clamping groove 14 for accommodating a sealing rubber ring is arranged at the edge of the hollow window.

In a preferred embodiment, the metal-based circuit board 4 is an aluminum-based circuit board.

The foregoing examples are illustrative only and are not intended to be limiting. Any equivalent modifications or variations without departing from the spirit and scope of the present application should be included in the scope of the claims of the present application.

Claims

1. A cooling channel structure for a multiplexed metal-based circuit board, comprising: casing (1), locate runner body (2) on the casing, locate inside cooling runner (3) of runner body, its characterized in that: at least one side of the side wall of the flow channel body is provided with a hollow window, the hollow window is plugged by a heat dissipation surface of the metal base circuit board (4), one side of the metal base circuit board with the electronic element (5) deviates from the hollow window, and a sealing device is arranged between the heat dissipation surface of the metal base circuit board and the edge of the hollow window.

2. The cooling channel structure of the multiplexing metal base circuit board of claim 1, wherein: the metal-based circuit board comprises an electronic element (5), a copper foil layer (4 a), an insulating layer (4 b) and a metal substrate (4 c) which are sequentially stacked, and the outer side face of the metal substrate (4 c) is the heat dissipation face.

3. The cooling channel structure of the multiplexing metal base circuit board of claim 2, wherein: and a plurality of corrugated grooves (4 e) are arranged on the heat dissipation surface of the metal base circuit board (4), and the directions of the corrugated grooves are vertical to the direction of water flow in the cooling flow channel (3).

4. The cooling channel structure of the multiplexing metal base circuit board of claim 3, wherein: be equipped with through-hole (4 f) on the border of metal base circuit board (4), the border of fretwork window is equipped with screw hole (8), and screw (7) pass through-hole and screw hole spiro union to plug up fretwork window with metal base circuit board (4).

5. The cooling channel structure of the multiplexing metal base circuit board of claim 4, wherein: the screw (7) penetrates through the insulating sleeve (9) and then is inserted into the through hole (4 f), and the nut of the screw (7) sinks into the groove of the insulating sleeve (9).

6. The cooling channel structure of the multiplexing metal base circuit board of claim 1, wherein: and a turbulence generator (10) is arranged on the inner side wall of the cooling flow channel (3).

7. The cooling channel structure of the multiplexing metal base circuit board of claim 1, wherein: the cooling flow channel (3) is in a strip shape and is bent into a U-shaped arrangement, a water inlet (11) and a water outlet (12) are respectively arranged at two ends of the cooling flow channel, the longitudinal section of the cooling flow channel (3) is in an open deep groove shape, and a cooling flow channel cover plate (13) is arranged at the opening of the cooling flow channel (3).

8. The cooling channel structure of the multiplexing metal base circuit board of claim 7, wherein: the metal-based circuit board (4) is arranged on the outward side wall of the U-shaped cooling flow channel (3), and a heating element can be arranged in the bent inward middle part of the U-shaped cooling flow channel (3).

9. The cooling channel structure of the multiplexing metal base circuit board of claim 1, wherein: an insulating frame (20) is arranged between the metal base circuit board (4) and the hollow window, the insulating frame adopts a window frame structure, and the cross section of the insulating frame is L-shaped; the metal base circuit board (4) is placed in the insulating frame, the periphery of the metal base circuit board is an insulating frame side wall, and an insulating frame bottom wall is arranged between the metal base circuit board and the hollow window.

10. The cooling channel structure of the multiplexing metal base circuit board of claim 9, wherein: one surface of the metal-based circuit board (4) with the electronic element (5) is poured with a layer of pouring sealant (21), and the outer surface of the pouring sealant is covered with an insulating plate (22).

11. The cooling channel structure of the multiplexing metal base circuit board of any of claims 1 to 10, wherein: the sealing device adopts a sealing rubber ring (6), and the metal-based circuit board (4) adopts an aluminum-based circuit board.

12. The utility model provides a vehicle-mounted charger, includes charging circuit and cooling system, its characterized in that: the cooling system adopts the cooling flow channel structure of the multiplexing metal-based circuit board of any one of claims 1 to 11.