A cooling device for a power converter and a power converter

Abstract

The present invention discloses a power converter, which belongs to the technical field of power converters. The power converter includes a printed circuit board, a housing assembly and a connector, wherein the housing assembly includes a housing and an upper cover plate and a lower cover plate arranged on the housing, the housing is provided with an installation cavity and a connecting groove, the upper cover plate and the installation cavity form a receiving space, the printed circuit board is arranged in the receiving space, the lower cover plate and the connecting groove form a water channel, and a coolant is passed into the water channel to cool the printed circuit board in the receiving space; the connector is detachably installed on the housing, one end of the connector is electrically connected to the external wiring harness of the power converter, and the other end is electrically connected to the printed circuit board. The power converter of the present invention improves the integration, simplifies the structure, reduces the structural volume, and reduces the cost.

Description

Technical Field

[0001] The present invention relates to the technical field of power converters, and in particular to a cooling device for a power converter and a power converter. Background Art

[0002] Power converters are used to convert DC voltage into lower or higher DC voltage and are widely used. High-power power converters generate heat during use and need to be cooled to extend their service life. In the prior art, one way is to set the power converter and the cooling device independently. This design method is simple, easy to maintain and detect, but it takes up a lot of space, is heavy, and has a high cost. Another way is to set the power converter and the cooling device as an integrated structure, but its structure is complex, the number of parts is large, the assembly process is complex, the reliability is poor, the cost is high, and the heat dissipation performance is poor. Summary of the invention

[0003] The object of the present invention is to provide a power converter which improves integration, simplifies structure, reduces structure volume and reduces cost.

[0004] To achieve this object, the present invention adopts the following technical solutions:

[0005] A power converter, comprising:

[0006] Printed circuit boards;

[0007] A housing assembly comprises a housing and an upper cover plate and a lower cover plate arranged on the housing, wherein a mounting cavity and a connecting groove are provided on the housing, wherein the upper cover plate and the mounting cavity form a receiving space, wherein the printed circuit board is arranged in the receiving space, and wherein the lower cover plate and the connecting groove form a water channel, wherein a coolant is introduced into the water channel for cooling the printed circuit board in the receiving space;

[0008] The connector is detachably mounted on the housing, one end of the connector is electrically connected to the external wiring harness of the power converter, and the other end is electrically connected to the printed circuit board.

[0009] Optionally, the lower cover plate is welded to the shell.

[0010] Optionally, a first water pipe and a second water pipe are also provided on the shell, and the first water pipe and the second water pipe are respectively connected to the connecting groove, one of the first water pipe and the second water pipe is used for water inlet into the water channel, and the other is used for water outlet from the water channel, and the first water pipe and the second water pipe are both integrally formed with the shell.

[0011] Optionally, guide ribs are provided on the connecting grooves to separate the connecting grooves, and the guide ribs separate the water channel into diversion channels.

[0012] Optionally, at least two guide ribs are provided on the connecting groove, the cross-sectional area of ​​any one of the diversion channels is S1, and the cross-sectional area of ​​the other diversion channels is S2, wherein 0.8≤S1 / S2≤1.2.

[0013] Optionally, a power device and a control device are arranged on the printed circuit board, a retaining wall is arranged in the shell, the printed circuit board abuts against the retaining wall, and the retaining wall is arranged around the outside of the connector to isolate the power device and the control device from the connector.

[0014] Optionally, the connector includes:

[0015] A first connector is provided with a first power terminal, a first end of the first power terminal is connected to an external wiring harness;

[0016] The second connector is provided with a second power terminal. The second end of the first power terminal is fixed and electrically connected to the second power terminal. The first power terminal is electrically connected to the printed circuit board through the second power terminal.

[0017] Optionally, the connector further includes a magnetic ring, which is bonded to the second connector.

[0018] Optionally, the busbar is fixed to the back side of the printed circuit board, and the side of the busbar away from the printed circuit board is the shell.

[0019] Optionally, the busbar is flat and laid flat on the back of the printed circuit board; or

[0020] The busbar is in an arch shape, and both ends of the busbar are fixed to the back side of the printed circuit board.

[0021] Beneficial effects of the present invention:

[0022] The present invention provides a power converter, wherein a shell and a lower cover plate form a water channel for cooling, and the shell and an upper cover plate form a receiving space for providing a fixing point and an installation space for a printed circuit board. The shell assembly integrates the water channel, the printed circuit board and the connector, thereby improving the structural integration, reducing the structural volume, simplifying the structure, reducing the cost and improving the heat dissipation performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic structural diagram of a power converter provided by a specific embodiment of the present invention from a first perspective;

[0024] Figure 2 is a structural schematic diagram of a housing provided by a specific embodiment of the present invention from a first viewing angle;

[0025] Figure 3is a structural schematic diagram of a housing provided by a specific embodiment of the present invention from a second viewing angle;

[0026] Figure 4 is an exploded view of a power converter provided by a specific embodiment of the present invention;

[0027] Figure 5 is a schematic structural diagram of a power converter provided in a specific embodiment of the present invention from a second viewing angle;

[0028] Figure 6 It is a structural schematic diagram of a connector and a housing provided in a specific embodiment of the present invention;

[0029] Figure 7 It is a structural schematic diagram of a connector provided in a specific embodiment of the present invention;

[0030] Figure 8 It is a structural explosion diagram of a power converter provided in a specific embodiment of the present invention.

[0031] In the figure:

[0032] 1. Printed circuit board; 11. Busbar;

[0033] 2. Connector; 21. First connector; 211. First power terminal; 2111. Terminal stud; 212. Signal terminal; 213. First body; 22. Second connector; 221. Second power terminal; 2211. Differential mode inductor terminal; 2212. Common mode capacitor terminal; 222. Second body; 2221. Semicircular rib; 23. Magnetic ring;

[0034] 3. Shell assembly; 31. Upper cover; 32. Shell; 321. Retaining wall; 3211. Screw hole; 322. Connecting groove; 3221. Guide rib; 323. First water pipe; 324. Second water pipe; 325. Installation cavity; 3251. First heat dissipation part; 3252. Second heat dissipation part; 3253. Third heat dissipation part; 33. Lower cover; 34. Sealant layer. DETAILED DESCRIPTION

[0035] In order to make the technical problems solved by the present invention, the technical solutions adopted and the technical effects achieved clearer, the technical solutions of the embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0036] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0038] This embodiment provides a power converter, such as Figure 1-Figure 8 As shown, it includes a housing assembly 3, a printed circuit board 1 and a connector 2. Specifically, the housing assembly 3 includes a housing 32 and an upper cover plate 31 and a lower cover plate 33 arranged on the housing 32. The housing 32 is provided with an installation cavity 325 and a connecting groove 322. The upper cover plate 31 and the installation cavity 325 form a receiving space. The printed circuit board 1 is arranged in the receiving space. The lower cover plate 33 and the connecting groove 322 form a water channel. The coolant is passed into the water channel to cool the printed circuit board 1 in the receiving space. The connector 2 is detachably installed on the housing 32. One end of the connector 2 is electrically connected to the external wiring harness of the power converter, and the other end is electrically connected to the printed circuit board 1.

[0039] The housing 32 and the lower cover plate 33 form a water channel for cooling, and the housing 32 and the upper cover plate 31 form a receiving space for providing a fixing point and installation space for the printed circuit board 1. The housing assembly 3 integrates the water channel, the printed circuit board 1 and the connector 2, thereby improving the structural integration, reducing the structural volume, simplifying the structure and reducing the cost. To further improve the reliability of the power converter, the following are specifically provided:

[0040] Referring to the prior art, the lower cover plate 33 can be installed on the opening of the connecting groove 322 by a detachable connection method such as snap connection or screw fixing, and a sealing ring or metal gasket is provided between the lower cover plate 33 and the connecting groove 322 to achieve the sealing between the lower cover plate 33 and the connecting groove 322. However, this connection method has a complex structure and is inconvenient to operate. In order to simplify the structure, improve the cooling performance of the power converter, and reduce the risk of cooling water leakage, the lower cover plate 33 is optionally welded to the shell 32, the connection is reliable, the risk of water channel leakage is reduced, and the reliability of the cooling device is improved. The lower cover plate 33 and the shell 32 are welded, and the process is simple and reliable; specifically, the lower cover plate 33 and the shell 32 can be made of the same material or different materials. In this embodiment, preferably, the lower cover plate 33 is bonded or welded to the opening of the connecting groove 322 to achieve the sealing assembly between the lower cover plate 33 and the connecting groove 322. Specifically, the lower cover plate 33 and the shell 32 are welded by stir friction welding to facilitate the connection between the lower cover plate 33 and the shell 32 of the same material or different materials; optionally, the lower cover plate 33 and the shell 32 are both made of metal.

[0041] To further simplify the structure, improve the cooling performance of the power converter, and reduce the risk of cooling water leakage. Figure 1 and Figure 2 As shown, the shell 32 is also provided with a first water pipe 323 and a second water pipe 324, which are respectively connected to the connecting groove 322. One of the first water pipe 323 and the second water pipe 324 is used for water inlet to the water channel, and the other is used for water outlet to achieve the circulation of the coolant in the water channel; specifically, a water pump is provided outside the power converter, and the water from the water pump enters the connecting groove 322 through the first water pipe 323 and is discharged through the second water pipe 324, forming a cooling water channel in the connecting groove 322 to improve the heat dissipation effect. Specifically, the first water pipe 323 and the second water pipe 324 are integrally formed with the shell 32, which simplifies the structure, reduces the assembly process steps, reduces the risk of leakage at the connection, and further improves the reliability of the cooling device.

[0042] Since the water pipes occupy a large space, when the first water pipe 323 and the second water pipe 324 are arranged on both sides of the shell 32, both sides need to occupy a large space, resulting in low space utilization. Optionally, the first water pipe 323 and the second water pipe 324 are on the same side of the shell 32, saving space on the other side of the shell 32 and improving space utilization; the first water pipe 323 and the second water pipe 324 are symmetrically arranged, which improves the appearance of the cooling device.

[0043] In the existing design, when the coolant flows in the water pipe, dead zones are likely to occur, resulting in poor cooling effect. Figure 2 and Figure 3 As shown, a guide rib 3221 is provided on the connecting groove 322 to separate the connecting groove 322. The guide rib 3221 separates the water channel into a diversion channel. The coolant flows in the diversion channel, which reduces the flow dead zone of the coolant in the water channel, improves the smoothness of the coolant circulation, and thus improves the heat dissipation efficiency.

[0044] According to the flow formula 1 and Bernoulli equation 2,

[0045] Q = Sv = constant (1)

[0046] P+(1 / 2)ρv 2 +ρgh=C (2)

[0047] in,

[0048] Q is the flow rate, S is the cross-sectional area, and v is the water velocity;

[0049] P is the pressure at a certain point in the fluid, v is the flow velocity of the fluid at that point, ρ is the fluid density, g is the acceleration due to gravity, h is the height of the point, and C is a constant.

[0050] According to the Bernoulli equation, the smaller the pressure difference in each diversion channel, the smaller the flow velocity difference, and the better the cooling effect; according to the flow formula, since the flow rate is a constant provided by the vehicle cooling system, the smaller the flow velocity difference, the smaller the cross-sectional area difference of each diversion channel, and it can be deduced that the closer the cross-sectional areas of each diversion channel are, the better the cooling effect of the cooling device.

[0051] Optionally, at least two guide ribs 3221 are provided on the connecting groove 322, the cross-sectional area of ​​any one of the diversion channels is S1, and the cross-sectional area of ​​the other diversion channels is S2, wherein 0.8≤S1 / S2≤1.2, so that the volume of each diversion channel is roughly equal, and the pressure of each diversion channel is roughly equal within this range, thereby reducing the pressure loss, reducing the flow velocity difference in different diversion channels, improving the heat dissipation efficiency, improving the uniformity of the coolant flow velocity in each diversion channel, and reducing the impact on the wall of the diversion channel.

[0052] Optionally, the guide rib 3221 is a smooth curved plate or a flat plate, and the specific shape can be set according to the shape of the water channel, so that the water flow in the water channel flows along the guide rib 3221, reducing the resistance of the guide rib 3221 to the flow of the coolant, thereby improving the circulation effect. Specifically, the guide rib 3221 is adapted to the shape of the groove wall of the connecting groove 322, so as to avoid a large angle between the guide rib 3221 and the groove wall of the connecting groove 322, which affects the circulation of the coolant. Specifically, the guide rib 3221 can be set by fluid simulation analysis. Specifically, a certain flow rate of the coolant can be given in the water channel, and when a vortex is formed at a position, the guide rib 3221 is added at the vortex position; a certain flow rate of the coolant can be given again, and when a vortex is generated, the number of the guide ribs 3221, the twisting direction or the structure of the guide rib 3221 is adjusted; the above process is repeated to eliminate the influence of the vortex.

[0053] In this embodiment, Figure 2 As shown, 7 guide ribs 3221 are arranged in the connecting groove 322, and the cross-sectional area of ​​each shunt channel is roughly the same, and the flow rate is uniform, which improves the cooling effect, and the flow rate is less than 5m / s, which reduces the impact force; specifically, the calculation can be performed based on the fluid simulation, and the pressure difference between each shunt channel can be inferred according to the required cooling efficiency, and the preset pressure difference can be obtained. When the pressure difference is less than the preset pressure difference, the cooling requirement can be met; the relationship between the cross-sectional areas of each shunt channel can be inferred based on the pressure difference. Preferably, S1=S2, the difference in the cross-sectional area of ​​each shunt channel reaches the minimum value, v1=v2, at this time, the pressure at each point in the water channel is equal, the flow rate of each shunt channel through the cross section is the same, and the cooling efficiency is the highest.

[0054] Optionally, one end of the guide rib 3221 away from the bottom of the connecting groove 322 abuts against the lower cover plate 33, that is, the height of the guide rib 3221 is flush with the lower cover plate 33, thereby improving the diversion effect of the diversion channel on the coolant. Optionally, the thickness of the guide rib 3221 is 2.5mm-3.5mm, so as to avoid the guide rib 3221 being too thick and reducing the volume of the diversion channel, and to avoid the guide rib 3221 being too thin and causing insufficient structural strength. Preferably, the thickness of the guide rib 3221 is 3mm.

[0055] Optionally, the guide rib 3221 is perpendicular to the bottom of the connecting groove 322, which is convenient for processing and forming. In this embodiment, the guide rib 3221 is integrally formed with the shell 32, which simplifies the structure, reduces the assembly process steps, and further improves the reliability of the structural connection. In other embodiments, the guide rib 3221 and the shell 32 are split structures. Specifically, the guide rib 3221 can be bonded or welded to the shell 32, and the guide rib 3221 can also be detachably connected to the shell 32 by fasteners.

[0056] Optionally, a power device and a control device are arranged on the printed circuit board 1, a retaining wall 321 is arranged in the housing 32, the printed circuit board 1 is installed in the housing 32, and the printed circuit board 1 abuts against the retaining wall 321. After the connector 2 is connected to the printed circuit board 1, radiation interference is generated during operation, and the retaining wall 321 is arranged around the outside of the connector 2, and the height of the retaining wall 321 is higher than the height of the connection port of the connector 2, so that the power device and the control device are separated from the connector 2, and the radiation interference is completely blocked in space from being transmitted inward or outward through the connection part of the connector 2, which can play a good shielding role, thereby improving the radiation interference performance of electromagnetic compatibility.

[0057] Preferably, the retaining wall 321 is provided with a screw hole 3211, and the printed circuit board 1 is provided with a fixing hole, and the screw is passed through the fixing hole and threadedly connected to the screw hole 3211, so that the printed circuit board 1 is fixed above the retaining wall 321. Furthermore, the common mode noise on the printed circuit board 1 can be transmitted to the housing 32 through the metal screws and the retaining wall 321, so as to better eliminate the common mode noise. In other embodiments, the top surface of the retaining wall 321 is provided with a welding pin, and the printed circuit board 1 is provided with a welding hole, and the welding pin can be passed through the welding hole, and the welding pin is welded to the welding hole.

[0058] Further preferably, the retaining wall 321 and the shell 32 are made of metal, and the retaining wall 321 and the shell 32 are integrally formed by a casting process. Cast aluminum material has a better effect of isolating electromagnetic interference, and there is no gap between the retaining wall 321 and the shell 32, which improves the dissipation of common mode noise. Of course, in other embodiments, the retaining wall 321 and the shell 32 can also be a split structure. In this embodiment, preferably, the retaining wall 321 and the shell 32 are made of cast aluminum, which saves processing costs and meets performance requirements. In other embodiments, other metals such as stainless steel, ordinary cold-rolled plate, aluminum plate, hot-dip galvanized steel plate, aluminum alloy plate and sandwich color steel plate can also be used.

[0059] Optionally, the connector 2 includes a first plug connector 21 and a second plug connector 22, wherein the first plug connector 21 is provided with a first power terminal 211, the first end of the first power terminal 211 is connected to an external wiring harness, the first end of the first power terminal 211 is provided with a terminal stud 2111, and the first end of the first power terminal 211 is connected to the external power wiring harness through the terminal stud 2111. Preferably, in this embodiment, the first plug connector 21 also includes a signal terminal 212, one end of the signal terminal 212 is connected to the external signal wiring harness, and the other end is connected to the printed circuit board 1 to achieve signal transmission. The second plug connector 22 is arranged below the printed circuit board 1, and the second plug connector 22 is provided with a second power terminal 221, the second end of the first power terminal 211 is fixed and electrically connected to the second power terminal 221, and the first power terminal 211 is electrically connected to the printed circuit board 1 through the second power terminal 221 to achieve circuit connection. In this embodiment, the connector 2 is a split structure, which reduces the volume of the terminals inside the connector 2 and simplifies the mold structure. Compared with the connectors in the prior art, the first connector 21 and the second connector 22 have a reduced volume of the internal terminals of each connector, a simple product design, and a simplified mold structure; the two independent connectors are smaller in volume, and the plastic wrapping area on the copper bus is small, which is not easy to crack and leak.

[0060] Preferably, in this embodiment, the first power terminal 211 and the second power terminal 221 are connected by welding, wherein the welding method is brazing connection. In other embodiments, the first power terminal 211 and the second power terminal 221 are connected by screws. The above method not only realizes a fixed connection between the two, but also realizes an electrical connection between the two.

[0061] In this embodiment, the first plug connector 21 includes a first body 213, a first power terminal 211 and a signal terminal 212 are disposed in the first body 213, the first body 213 is made of plastic, and the first body 213, the first power terminal 211 and the signal terminal 212 are integrally formed by an injection mold. The second plug connector 22 includes a second body 222, a second power terminal 221 is disposed in the second body 222, the second body 222 is made of plastic, and the second body 222 and the second power terminal 221 are integrally formed by an injection mold.

[0062] In the prior art, the terminal structure in the connector is complex. Due to the problem of injection mold manufacturing process, it is difficult to make the terminal into a compact structure, and it is impossible to connect the differential mode inductor to reduce the electromagnetic interference of the connector to the external device. In this embodiment, the terminal structure in the second connector 22 is simple, so the differential mode inductor terminal 2211 can be set on the second power terminal 221, and the differential mode inductor is set on the printed circuit board 1. The differential mode inductor terminal 2211 is electrically connected to the differential mode inductor on the printed circuit board 1 to reduce the electromagnetic interference of the connector 2 to the external device.

[0063] Optionally, the connector 2 further includes a magnetic ring 23 , which is bonded to the second connector 22 .

[0064] Specifically, a mounting position is provided on the second body 222 of the second connector 22, and the magnetic ring 23 is installed in the mounting position, and the magnetic ring 23 is arranged outside the differential mode inductor terminal 2211. The arrangement of the magnetic ring 23 can suppress the transmission of electromagnetic radiation inward or outward, thereby improving the electromagnetic compatibility performance. Further preferably, the mounting position is a mounting rib. It should be noted that the magnetic ring 23 in this embodiment is an EMC magnetic ring.

[0065] Preferably, in this embodiment, the mounting ribs are at least two semicircular ribs 2221 arranged opposite to each other, and the magnetic ring 23 is bonded between the semicircular ribs 2221 by glue dispensing. In other embodiments, the magnetic ring 23 can be snapped into the mounting ribs. Alternatively, the magnetic ring 23 is installed between the mounting ribs, and the mounting ribs are provided with threaded holes, and the bolts are threadedly connected to the threaded holes so that the end faces of the bolts abut against the magnetic ring 23.

[0066] In this embodiment, the differential mode inductor terminal 2211 includes a plurality of differential mode inductor sub-terminals, and the plurality of differential mode inductor sub-terminals are arranged in a circle with a diameter not greater than 17 mm; and the spacing between the plurality of differential mode inductor sub-terminals is not less than 3 mm, meeting the requirements of HTE (Hazardous Thermal Event) to prevent internal short circuits between the differential mode inductor sub-terminals. In this embodiment, there are three differential mode inductor sub-terminals, namely, a 12V differential mode inductor terminal, a 48V differential mode inductor terminal and a ground differential mode inductor terminal, the distance between the 48V differential mode inductor terminal and the ground differential mode inductor terminal is 5 mm, and the distance between the ground differential mode inductor terminal and the 12V differential mode inductor terminal is 3.3 mm. In this embodiment, the inner diameter of the magnetic ring 23 is 19 mm, and the outer diameter of the magnetic ring 23 is 38 mm. Further preferably, the outer surface of the magnetic ring 23 is also provided with an insulating coating, and the insulating coating is a polymer material (gum, rubber or animal glue), epoxy resin, etc., to prevent short circuits caused by the rupture of the magnetic ring 23.

[0067] Furthermore, a common-mode capacitor terminal 2212 is provided on the second power terminal 221 , and a common-mode capacitor is provided on the printed circuit board 1 . The common-mode capacitor terminal 2212 is electrically connected to the common-mode capacitor on the printed circuit board 1 , so that the circuit connection line is the shortest.

[0068] It should be noted that, in the present embodiment, the first power terminal 211 and the second power terminal 221 each include three corresponding terminals, and the three terminals are respectively a 12V terminal, a ground terminal and a 48V terminal. In order to meet the welding requirements, the surface of the terminal is plated, and the plating is one of tin, zinc, silver and nickel or any combination of at least two or more. The first end of each first power terminal 211 is provided with a terminal stud 2111 for connecting an external power harness. Each second power terminal 221 is provided with a differential mode inductor terminal 2211 and a common mode capacitor terminal 2212. In order to meet the peak current of 210A, the cross-sectional area of ​​the second power terminal 221 is designed to be 21mm 2 .

[0069] Alternatively, if Figure 5 and Figure 8 As shown, the printed circuit board 1 includes a busbar 11, which is fixed to the back of the printed circuit board 1, and the side of the busbar 11 away from the printed circuit board 1 is a housing 32. Since there are fewer electronic components on the back of the printed circuit board 1, the busbar 11 can be horizontally arranged and both ends are welded to the back of the printed circuit board 1, which increases the fixing strength of the busbar 11.

[0070] Optionally, the busbar 11 is flat and laid flat on the back of the printed circuit board 1; or the busbar 11 is arched and both ends of the busbar 11 are fixed to the back of the printed circuit board 1. Moreover, the busbar 11 is provided with a through hole in the center along the length direction; or the busbar 11 is provided with a cavity with one end open in the center along the length direction, both of which can meet the use requirements.

[0071] Preferably, since some components on the back side of the printed circuit board 1 are higher than the height of the busbar 11, in order to avoid the higher components and reduce the distance between the shell 32 and the busbar 11, the shell 32 is recessed with a connecting groove 322, the position of the connecting groove 322 matches the position of the busbar 11, and the bottom wall of the connecting groove 322 is coated with a heat dissipation medium to facilitate the conduction of the heat generated by the busbar to the water channel, while reducing the distance between the shell 32 and the busbar 11.

[0072] Furthermore, in this embodiment, the length direction of the busbar 11 is axial, and the effective cross-sectional area of ​​the busbar 11 along the length direction in the radial direction must satisfy the unit area (mm 2 ) The overcurrent is not greater than 10A. In this embodiment, the maximum carrying current of busbar 11 in the power converter is 210A. According to the formula: actual current / cross-sectional area ≤ 10A / mm 2 In this embodiment, the effective cross-sectional area of ​​busbar 11 is not less than 21 mm2 . Further preferably, if the height of busbar 11 is too high, it is difficult to stamp; if the width of busbar 11 is too large, the water channel does not have enough area to dissipate heat; if the length of busbar 11 is too long, it is difficult to process, the product dimensional stability is poor, and it is easy to fall off during vibration. Therefore, in this embodiment, the length, width and height of busbar 11 are 25mm, 7mm and 3mm respectively.

[0073] Preferably, in this embodiment, the outer surface of busbar 11 is provided with a solder coating, and busbar 11 is soldered to the back of printed circuit board 1 by double-sided reflow soldering through the solder coating, which improves the assembly efficiency of busbar 11 compared with the assembly method of the prior art. In this embodiment, the solder coating is one of tin, zinc, silver and nickel, or any combination of at least two or more.

[0074] Optionally, electronic components such as capacitors and inductors are also provided on the printed circuit board 1, and the electronic components are soldered to the printed circuit board 1 through a double-sided reflow soldering process. Specifically, the printed circuit board 1 is fixed to the housing 32 by bolts to ensure a stable structural installation. The waterway channel can reduce the heat generated by electronic components such as inductors and capacitors, thereby increasing the service life of the electronic components and thus increasing the service life of the power converter.

[0075] To improve the cooling effect, specifically, the first cavity of the installation cavity 325 for installing the inductor is sunk between the connecting grooves 322, so that the connecting grooves 322 are divided into a first connecting groove and a second connecting groove, the first connecting groove and the second connecting groove are connected, and the first connecting groove and the second connecting groove are arranged on both sides of the first cavity; when the printed circuit board 1 is arranged in the installation cavity 325, the cooling water in the first connecting groove and the second connecting groove on both sides of the first cavity cools the inductor in the first cavity at the same time, thereby improving the cooling effect.

[0076] When the heat of the printed circuit board 1 is directly conducted through the water pipe, the heat dissipation efficiency is low. For example, the heat dissipation of the chip capacitor is also limited to the heat dissipation glue applied to the bottom, which may cause the heat generated by the capacitor to not be conducted out in time. For this reason, optionally, a heat dissipation part is provided in the installation cavity 325, and the printed circuit board 1 is provided on the heat dissipation part. The printed circuit board 1 transfers the generated heat to the water channel through the heat dissipation part, thereby improving the heat conduction between the printed circuit board 1 and the water channel, so as to facilitate heat exchange through the coolant, and further improve the heat dissipation efficiency. Optionally, the heat dissipation part is adapted to the shape of the printed circuit board 1, and a heat dissipation glue layer is provided between the heat dissipation part and the printed circuit board 1. The heat dissipation glue layer improves the heat conduction between the printed circuit board 1 and the heat dissipation part, thereby improving the cooling effect.

[0077] In this embodiment, Figure 5 and Figure 8As shown, the printed circuit board 1 is provided with a busbar 11 and electronic components such as capacitors, and the heat dissipation portion includes at least a first heat dissipation portion 3251 and a second heat dissipation portion 3252. Specifically, as shown in FIG. Figure 3 As shown, the first heat dissipation portion 3251 is adapted to the shape of the capacitor. In this embodiment, the capacitor is cylindrical, and the first heat dissipation portion 3251 is arc-shaped. The arc-shaped first heat dissipation portion 3251 can cooperate with the cylindrical capacitor to increase the contact area between the capacitor and the heat dissipation adhesive layer, thereby increasing the heat conduction between the capacitor and the first heat dissipation portion 3251 and improving the heat dissipation effect. Specifically, a heat dissipation adhesive is coated between the first heat dissipation part 3251 and the capacitor to form a heat dissipation adhesive layer, which further improves the heat dissipation effect between the capacitor and the first heat dissipation part 3251; similarly, in this embodiment, the busbar11 is arranged on the second heat dissipation part 3252, and the surface where the busbar11 contacts the second heat dissipation part 3252 is a planar structure, and the second heat dissipation part 3252 is also a planar structure, which increases the contact area between the busbar11 and the second heat dissipation part 3252, thereby improving heat conduction, thereby improving the heat dissipation effect. Specifically, a heat dissipation adhesive is coated between the second heat dissipation part 3252 and the busbar11, which further improves the heat dissipation effect between the busbar11 and the second heat dissipation part 3252; similarly, in this embodiment, the heat dissipation part also includes a third heat dissipation part 3253. In addition to the capacitor and the busbar11, the printed circuit board 1 is also provided with a high-power MOSFET structure. The high-power MOSFET corresponds to the third heat dissipation part 3253 and is coated with a heat dissipation adhesive layer, which improves the heat dissipation effect.

[0078] A heat dissipation adhesive layer is provided on the installation cavity 325. Specifically, the heat dissipation adhesive is filled between the printed circuit board 1 and the housing 32. The heat dissipation adhesive will conduct the heat emitted by the electronic components on the printed circuit board 1 when working to the housing 32, playing a heat dissipation role, so as to improve the heat transfer from the printed circuit board 1 to the housing 32. After the cooling water is introduced into the water channel, the cooling water flows to take away the heat conducted by the heat dissipation adhesive layer, avoiding the electronic components on the printed circuit board 1 from malfunctioning due to excessive temperature, thereby improving the cooling efficiency of the power converter. Optionally, the housing 32 is a metal housing with good heat dissipation performance.

[0079] Similarly, optionally, a thermally conductive insulating gasket may be provided between the heat dissipation part and the printed circuit board 1, and the thermally conductive insulating gasket improves the heat conduction between the printed circuit board 1 and the heat dissipation part, thereby improving the cooling effect. The thermally conductive insulating gasket is directly installed between the first heat dissipation part 3251 and the capacitor, thereby improving the heat dissipation effect between the capacitor and the first heat dissipation part 3251; the thermally conductive insulating gasket is directly installed between the second heat dissipation part 3252 and the busbar, thereby improving the heat dissipation effect between the second heat dissipation part 3252 and the busbar. The thermally conductive insulating gasket is directly installed between the third heat dissipation part 3253 and the printed circuit board 1 corresponding to the high-power mosfet, thereby improving the heat dissipation effect between the third heat dissipation part 3253 and the high-power mosfet. The use of heat dissipation glue or thermally conductive insulating gasket can be selected according to actual conditions, without limitation.

[0080] In this embodiment, the heat dissipation part and the housing 32 are integrally formed, which simplifies the structure and further improves the reliability of the structural connection. In other embodiments, the heat dissipation part and the housing 32 are separate structures.

[0081] Optionally, the upper cover plate 31 is detachably connected to the housing 32, and the upper cover plate 31 is used to protect the printed circuit board 1 in the installation cavity 325 from being impacted by foreign objects, thereby avoiding damage to electronic components and short circuits, and improving the reliability of the printed circuit board 1. Optionally, the upper cover plate 31 is a stamped cover plate, a mounting hole is formed on the stamped cover plate, and a corresponding connecting hole is formed on the housing 32, and the stamped cover plate and the housing 32 are detachably connected by fasteners penetrating the mounting hole and the connecting hole.

[0082] Optionally, a sealant layer 34 is provided between the upper cover plate 31 and the shell 32 to prevent liquid or solid particles from entering the interior of the product and damaging the structure of the printed circuit board 1, resulting in failure of the electrical performance of the printed circuit board 1. Specifically, the sealant is applied to the edge of the shell 32, and then the upper cover plate 31 is installed on the edge of the shell 32. The operation is simple and convenient, and the sealing reliability is good.

[0083] Optionally, a vent plug is provided on the shell 32, which has dust and water-proof functions and can effectively maintain the exchange of internal and external gases, thereby ensuring that harmful gases will not affect the normal operation of electronic components, further improving the reliability of the power converter.

[0084] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A power converter, characterized in that: include: Printed circuit board (1); A housing assembly (3), comprising a housing (32) and an upper cover plate (31) and a lower cover plate (33) arranged on the housing (32); a mounting cavity (325) and a connecting groove (322) are provided on the housing (32); the upper cover plate (31) and the mounting cavity (325) form a receiving space; the printed circuit board (1) is arranged in the receiving space; the lower cover plate (33) and the connecting groove (322) form a water channel; a coolant is passed into the water channel for cooling the printed circuit board (1) in the receiving space; A connector (2) detachably mounted on the housing (32), one end of the connector (2) being electrically connected to an external wiring harness of the power converter, and the other end of the connector (2) being electrically connected to the printed circuit board (1); The shell (32) is further provided with a first water pipe (323) and a second water pipe (324); the first water pipe (323) and the second water pipe (324) are respectively connected to the connecting groove (322); one of the first water pipe (323) and the second water pipe (324) is used for water inlet to the water channel, and the other is used for water outlet to the water channel; the first water pipe (323) and the second water pipe (324) are both integrally formed with the shell (32); The lower cover plate (33) is welded to the shell (32); The connecting groove (322) is provided with a guide rib (3221) to separate the connecting groove (322), and the guide rib (3221) separates the water channel into a diversion channel.

2. The power converter according to claim 1, characterized in that: At least two guide ribs (3221) are provided on the connecting groove (322), the cross-sectional area of ​​any one of the flow diversion channels is S1, and the cross-sectional area of ​​the other flow diversion channels is S2, wherein 0.8≤S1 / S2≤1.

2.

3. The power converter according to claim 1, wherein: A power device and a control device are arranged on the printed circuit board (1); a retaining wall (321) is arranged in the housing (32); the printed circuit board (1) abuts against the retaining wall (321); and the retaining wall (321) is arranged around the outside of the connector (2) so that the power device and the control device are isolated from the connector (2).

4. The power converter according to claim 3, characterized in that: The connector (2) comprises: A first connector (21) provided with a first power terminal (211), wherein a first end of the first power terminal (211) is connected to the external wiring harness; The second connector (22) is provided with a second power terminal (221), the second end of the first power terminal (211) is fixed to and electrically connected to the second power terminal (221), and the first power terminal (211) is electrically connected to the printed circuit board (1) via the second power terminal (221).

5. The power converter according to claim 4, characterized in that: The connector (2) further comprises a magnetic ring (23), wherein the magnetic ring (23) is bonded to the second connector (22).

6. The power converter according to claim 1, wherein: The printed circuit board (1) comprises a busbar (11), wherein the busbar (11) is fixed to the back side of the printed circuit board (1), and the side of the busbar (11) away from the printed circuit board (1) is the housing (32).

7. The power converter according to claim 6, characterized in that: The busbar (11) is flat, and the busbar (11) is laid flat on the back side of the printed circuit board (1); or The busbar (11) is in an arch shape, and two ends of the busbar (11) are fixed to the back side of the printed circuit board (1).

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