Power conversion equipment

Abstract

The utility model provides power conversion equipment which comprises a box body and a circuit board, the box body comprises a shell and a cover plate, the shell is provided with an accommodating cavity, the accommodating cavity is provided with an opening, and the cover plate covers the opening of the accommodating cavity and seals the accommodating cavity. The circuit board is contained in the containing cavity, the circuit board is provided with a DC-AC conversion circuit and a capacitor, and the DC-AC conversion circuit is used for converting direct current from the photovoltaic module or the energy storage battery into alternating current. The surface, facing the circuit board, of the cover plate comprises a plurality of explosion venting grooves, and the depth of the explosion venting grooves is smaller than the thickness of the cover plate. And the design of the explosion venting groove can prevent the cover plate from being separated from the shell and prevent the cover plate from popping up to hurt people, so that the use safety of the power conversion equipment is higher.

Description

Technical Field

[0001] The present application relates to the field of power electronics, and in particular to a power conversion device. Background Art

[0002] A photovoltaic inverter is an electronic device used to convert the direct current output by a photovoltaic module into alternating current. The circuit board of the photovoltaic inverter is housed in a box. When the circuit board is working, the film inside the capacitor on the circuit board will produce flammable gases such as hydrogen or methane. When the capacitor fails, the film inside the capacitor will produce too much flammable gas, which will cause the air pressure inside the box to rise sharply. The excessive flammable gas will cause a violent chemical reaction and cause an explosion, resulting in the separation of the cover and the shell of the box, and the cover will pop out and injure people. The use safety of the photovoltaic inverter is low. Utility Model Content

[0003] The present application provides a power conversion device, aiming to solve the problem that the cover plate and the shell of the box body are easy to separate and the power conversion device has low safety in use.

[0004] The embodiment of the present application provides a power conversion device, which includes: a box body, the box body includes a shell and a cover plate, the shell is provided with a receiving cavity, the receiving cavity has an opening, and the cover plate covers the opening of the receiving cavity and closes the receiving cavity. And a circuit board, the circuit board is received in the receiving cavity, and the circuit board is provided with a DC-AC conversion circuit and a capacitor, wherein the DC-AC conversion circuit is used to convert direct current from a photovoltaic module or an energy storage battery into alternating current. The surface of the cover plate facing the circuit board includes a plurality of explosion venting grooves, and the depth of the explosion venting grooves is less than the thickness of the cover plate.

[0005] In the power conversion device provided in the embodiment of the present application, an explosion relief groove is provided on the cover plate to weaken the local structural strength of the cover plate. When the circuit board accommodated in the receiving chamber is working, the thin film in the capacitor on the circuit board will generate flammable gas. When the air pressure in the receiving chamber rises sharply, the gas pressure acts on the cover plate, causing the cover plate to deform at the position where the explosion relief groove is provided, thereby achieving directional deformation of the cover plate. After the cover plate is deformed, the space of the receiving chamber becomes larger, and the air pressure in the receiving chamber becomes smaller as the space of the receiving chamber becomes larger, thereby preventing the cover plate from separating from the shell due to excessive air pressure in the receiving chamber, avoiding the cover plate from popping out and injuring people, and making the power conversion device safer to use.

[0006] In addition, when the air pressure in the containment chamber is too high, the cover plate bursts at the corresponding position of the explosion venting groove to form a gap, and the combustible gas can be discharged from the gap to the outside of the box, thereby preventing the air pressure in the containment chamber from continuing to increase and causing the cover plate and the shell to separate. At the same time, it can also prevent the power conversion equipment from exploding due to excessive combustible gas in the containment chamber.

[0007] In some embodiments, the housing includes two first frames and two second frames. The two first frames are arranged opposite to each other, the two second frames are arranged opposite to each other, and the two second frames are fixedly connected between the two first frames.

[0008] The power conversion device comprises a plurality of first fasteners, which respectively fix the cover plate to the two first frames, wherein the plurality of first fasteners located on the first frames are arranged at intervals along the length direction of the first frames.

[0009] The power conversion device comprises a plurality of second fasteners, which respectively fix the cover plate to the two second frames, wherein the plurality of second fasteners located on the second frames are arranged at intervals along the length direction of the second frames.

[0010] The spacing between two adjacent first fasteners among the multiple first fasteners located on the first frame is smaller than the spacing between two adjacent second fasteners among the multiple second fasteners located on the second frame, and the fastening force of the first fastener on the cover plate is greater than or equal to the fastening force of the second fastener on the cover plate.

[0011] Since the spacing between two adjacent first fasteners among the plurality of first fasteners located on the first frame is smaller than the spacing between two adjacent second fasteners among the plurality of second fasteners located on the second frame, and the fastening force of the first fastener on the cover plate is greater than or equal to the fastening force of the second fastener on the cover plate, the fastening force between the cover plate and the second frame is smaller than the fastening force between the cover plate and the first frame. Furthermore, when the air pressure in the receiving chamber is too high, the plurality of second fasteners located on the second frame will loosen, and a gap will appear between the cover plate and the second frame, and the combustible gas in the receiving chamber can be discharged from the gap to the outside of the box body, thereby preventing the combustible gas in the receiving chamber from exploding due to excessive gas.

[0012] In some embodiments, the housing includes two first frames and two second frames. The two first frames are arranged opposite to each other, the two second frames are arranged opposite to each other, and the two second frames are fixedly connected between the two first frames.

[0013] The power conversion device comprises a plurality of third fasteners, which respectively fix the cover plate to the two first frames, wherein the plurality of third fasteners located on the first frame are arranged at intervals along the length direction of the first frame.

[0014] The power conversion device comprises at least two fourth fasteners, wherein one fourth fastener fixes the cover plate to one second frame, and the other fourth fastener fixes the cover plate to another second frame.

[0015] The distance between the third fastener and the fourth fastener adjacent to the third fastener is greater than or equal to the distance between two adjacent third fasteners among the multiple third fasteners located on the first frame, and the fastening force of the third fastener on the cover plate is greater than the fastening force of the fourth fastener on the cover plate.

[0016] Since the distance between the third fastener and the fourth fastener adjacent to the third fastener is greater than or equal to the distance between two adjacent third fasteners among the multiple third fasteners located on the first frame, the fastening force of the third fastener on the cover is greater than the fastening force of the fourth fastener on the cover. When the air pressure in the receiving chamber is too high, the fourth fastener will loosen, and a gap will appear between the cover and the second frame. The combustible gas in the receiving chamber can be discharged from the gap to the outside of the box, thereby preventing an explosion due to excessive combustible gas in the receiving chamber.

[0017] In some embodiments, the plurality of third fasteners and at least two fourth fasteners are all in contact with the side of the cover plate facing away from the shell, and the contact area between the third fasteners and the cover plate is greater than the contact area between the fourth fasteners and the cover plate. In this embodiment, by setting the contact area between the third fasteners and the cover plate to be greater than the contact area between the fourth fasteners and the cover plate, the fastening force of the third fasteners on the cover plate is greater than the fastening force of the fourth fasteners on the cover plate, which has a simple structure and low cost.

[0018] In some embodiments, the depth of the explosion relief groove is less than or equal to half the thickness of the cover plate. The depth of the explosion relief groove is set within this range, which ensures that the cover plate has a certain structural strength while meeting the explosion relief requirements, and prevents the cover plate from being easily deformed during normal use.

[0019] In some embodiments, there are multiple explosion venting grooves, and the multiple explosion venting grooves are arranged crosswise with each other. The design of multiple explosion venting grooves arranged crosswise with each other is conducive to weakening the structural strength of the cover plate at the intersection of the multiple explosion venting grooves. When the air pressure in the receiving chamber is too high, the cover plate can burst at the intersection of the explosion venting grooves to form a gap, and the combustible gas in the receiving chamber can be discharged from the gap to the outside of the box body. The air pressure in the receiving chamber becomes smaller, preventing the cover plate from separating from the shell due to excessive air pressure in the receiving chamber, avoiding the cover plate from popping out and injuring people, and the power conversion equipment is safer. At the same time, it is conducive to preventing the power conversion equipment from exploding due to excessive combustible gas in the receiving chamber.

[0020] In some embodiments, there are multiple explosion relief grooves, and the multiple explosion relief grooves are arranged in a ring shape, and the multiple explosion relief grooves are evenly spaced from each other. The design of multiple explosion relief grooves being arranged in a ring shape and evenly spaced from each other is conducive to improving the uniformity of deformation of the cover plate, and is conducive to increasing the deformation amount of the cover plate, thereby making the space of the receiving cavity larger, and the gas pressure in the receiving cavity smaller, preventing the cover plate from separating from the shell due to excessive gas pressure in the receiving cavity, avoiding the cover plate from popping out and injuring people, and the power conversion device is safer to use.

[0021] In some embodiments, there are multiple explosion venting grooves, each of which is arranged on the diagonal of the cover plate, and each of which extends along the diagonal of the cover plate. When the cover plate is deformed and bulges, the deformation of the cover plate in the diagonal area is the largest. This embodiment is conducive to weakening the structural strength of the cover plate in the diagonal area by arranging the explosion venting grooves on the diagonal. When the air pressure in the receiving chamber is too high, the cover plate is more easily deformed in the diagonal area, and the deformation of the cover plate in the diagonal area is greater, so that the height of the cover plate bulges is higher, and then the space of the receiving chamber becomes larger, so as to reduce the air pressure in the receiving chamber to the greatest extent, prevent the cover plate and the shell from separating due to excessive air pressure in the receiving chamber, avoid the cover plate popping out and injuring people, and the power conversion equipment is safer to use.

[0022] In some embodiments, the box body is provided with an explosion venting hole, and the box body includes an explosion venting plate, which blocks the explosion venting hole and closes the receiving chamber. The gas pressure in the receiving chamber is concentrated on the explosion venting plate. When the gas pressure in the receiving chamber is too high, the explosion venting plate ruptures, and the gas in the receiving chamber can be discharged to the outside of the box body through the explosion venting plate, so that the gas pressure in the receiving chamber is reduced, and the cover plate is prevented from being separated from the shell due to the excessive gas pressure in the receiving chamber, and the cover plate is prevented from popping out and injuring people, and the power conversion device is safer to use.

[0023] In some embodiments, the explosion venting plate is provided with a first notch and a second notch, and the first notch and the second notch are arranged crosswise. By providing the first notch and the second notch to guide the explosion venting plate to rupture, when the gas pressure in the receiving chamber is too high, the explosion venting plate ruptures faster, the opening of the explosion venting plate ruptures is larger, and the combustible gas in the receiving chamber can be discharged to the outside of the box faster, and the gas pressure in the receiving chamber decreases faster, preventing the cover plate from separating from the shell due to excessive gas pressure in the receiving chamber, avoiding the cover plate from popping out and injuring people, and the power conversion device is safer to use.

[0024] The power conversion device provided in the embodiment of the present application is provided with an explosion relief groove on the cover plate to weaken the local structural strength of the cover plate. When the circuit board accommodated in the receiving chamber is working, the thin film in the capacitor on the circuit board will generate flammable gas. When the air pressure in the receiving chamber rises sharply, the gas pressure acts on the cover plate, causing the cover plate to deform at the position where the explosion relief groove is provided, thereby achieving directional deformation of the cover plate. After the cover plate is deformed, the space of the receiving chamber becomes larger, and the air pressure in the receiving chamber becomes smaller as the space of the receiving chamber becomes larger, thereby preventing the cover plate from separating from the shell due to excessive air pressure in the receiving chamber, avoiding the cover plate from popping out and injuring people, and thus improving the safety of the power conversion device.

[0025] In addition, when the air pressure in the containment chamber is too high, the cover plate bursts at the corresponding position of the explosion venting groove to form a gap, and the combustible gas can be discharged from the gap to the outside of the box, thereby preventing the air pressure in the containment chamber from continuing to increase and causing the cover plate and the shell to separate. At the same time, it can also prevent the power conversion equipment from exploding due to excessive combustible gas in the containment chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background technology, the drawings required for use in the embodiments of the present application or the background technology will be described below.

[0027] Figure 1 This is an application scenario diagram of a power conversion device provided in an embodiment of the present application.

[0028] Figure 2 A schematic diagram of the three-dimensional structure of a power conversion device provided in an embodiment of the present application.

[0029] Figure 3 yes Figure 2 The shown schematic diagram is a three-dimensional structural decomposition diagram of the power conversion device at another angle.

[0030] Figure 4 yes Figure 2 The schematic diagram of the three-dimensional structure of the housing of the power conversion device shown is shown at another angle.

[0031] Figure 5 yes Figure 2 The cover plate of the power conversion device shown is a schematic diagram of the three-dimensional structure at another angle.

[0032] Figure 6 yes Figure 2 The cover plate of the power conversion device shown is a schematic structural diagram at another angle.

[0033] Figure 7 yes Figure 2 The structure diagram of the power conversion device shown is cut along the line L1-L1.

[0034] Figure 8 yes Figure 2 The structure diagram of another embodiment of the cover plate of the power conversion device is shown.

[0035] Fig. 9 yes Figure 2 The structure diagram of another embodiment of the cover plate of the power conversion device is shown.

[0036] Fig.10 yes Figure 2 The structure diagram of another embodiment of the cover plate of the power conversion device is shown.

[0037] Fig.11 It is a schematic diagram of the three-dimensional structure of a power conversion device provided in another embodiment of the present application at another angle.

[0038] Fig.12 It is a schematic diagram of the three-dimensional structure of a power conversion device provided in another embodiment of the present application at another angle.

[0039] Fig.13 yes Figure 7 An enlarged view of portion A of the power conversion device is shown.

[0040] Fig.14 yes Figure 2 The schematic diagram of the three-dimensional structure of the explosion relief device of the power conversion equipment shown is shown in another angle.

[0041] Fig.15 yes Fig.14 The explosion relief piece of the explosion relief device shown is a schematic three-dimensional structure diagram at another angle.

[0042] Fig.16 yes Fig.14 The explosion relief device shown is a schematic structural diagram cut along the L2-L2 line.

[0043] Fig.17 yes Figure 2 The power conversion device shown is a schematic structural diagram of another embodiment cut along line L1 - L1 .

[0044] Fig.18 yes Fig.17 An enlarged view of part B of the power conversion device is shown.

[0045] Fig.19 yes Figure 2 The power conversion device shown is a schematic structural diagram of another embodiment cut along line L1 - L1 .

[0046] Fig. 20 yes Fig.19 An enlarged view of portion C of the power conversion device is shown.

[0047] Fig.21 It is a schematic diagram of the three-dimensional structure of a power conversion device provided in another embodiment of the present application at another angle.

[0048] Fig. 22 yes Fig.21 The power conversion device shown is a schematic structural diagram cut along line L3-L3.

[0049] Fig.23 yes Fig. 22 An enlarged view of portion D of the power conversion device is shown. DETAILED DESCRIPTION

[0050] Please refer to Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 , Figure 1 This is an application scenario diagram of a power conversion device provided in an embodiment of the present application. Figure 2 A schematic diagram of the three-dimensional structure of a power conversion device 1000 provided in an embodiment of the present application. Figure 3 yes Figure 2 The power conversion device 1000 is shown as a schematic diagram of a three-dimensional structure explosion at another angle. Figure 4 yes Figure 2 The shown schematic diagram is a three-dimensional structure of the housing 10 of the power conversion device 1000 at another angle. Figure 5 yes Figure 2 The cover plate 20 of the power conversion device 1000 is shown as a three-dimensional structural schematic diagram at another angle. Figure 6 yes Figure 2 The cover plate 20 of the power conversion device 1000 is shown as a schematic structural diagram at another angle. Figure 7 yes Figure 2 The power conversion device 1000 shown is a schematic structural diagram cut along L1-L1.

[0051] like Figure 1 As shown, illustratively, the power conversion device 1000 is a photovoltaic inverter. The power conversion device 1000 is electrically connected to the photovoltaic module 2000 and the power grid 3000. Specifically, the input end of the power conversion device 1000 is electrically connected to the photovoltaic module 2000, and the output end of the power conversion device 1000 is electrically connected to the power grid 3000. The direct current output by the photovoltaic module 2000 is transmitted to the power conversion device 1000, and the power conversion device 1000 is used to convert the direct current into alternating current. The alternating current output by the power conversion device 1000 is transmitted to the power grid 3000 to supply the power grid 3000. In some other embodiments, the power conversion device 1000 may also be other power conversion devices such as other inverters, rectifiers, voltage stabilizers or transformers. Figure 2 As shown, in this embodiment, the length direction of the power conversion device 1000 is the X-axis shown in the figure, the width direction of the power conversion device 1000 is the Y-axis shown in the figure, and the height direction of the power conversion device 1000 is the Z-axis shown in the figure.

[0052] like Figure 1 , Figure 2 and Figure 3 As shown, the power conversion device 1000 includes a housing 100 and a circuit board 200. The circuit board 200 is housed in the housing 100. The circuit board 200 is electrically connected to the photovoltaic module 2000 and the power grid 3000. Specifically, the circuit board 200 is provided with a DC-AC conversion circuit 201 and a capacitor 202. The input end of the DC-AC conversion circuit 201 is electrically connected to the photovoltaic module 2000, and the output end of the DC-AC conversion circuit 201 is electrically connected to the power grid 3000. The DC-AC conversion circuit 201 is used to convert the direct current from the photovoltaic module 2000 into alternating current, and transmit the converted alternating current to the power grid 3000. In some other embodiments, the DC-AC conversion circuit 201 is used to convert the direct current from the energy storage battery into alternating current. The capacitor 202 is used to filter the current transmitted in the DC-AC conversion circuit.

[0053] like Figure 2 , Figure 3 and Figure 4 As shown, the box 100 is exemplarily rectangular, and in some other embodiments, the box 100 may also be cylindrical or other special-shaped boxes 100. The box 100 includes a shell 10, a cover plate 20, and an explosion relief device 30. In the thickness direction (Z-axis direction) of the cover plate 20, the cover plate 20 is installed on one side of the shell 10. The explosion relief device 30 is installed on the shell 10. In some other embodiments, the explosion relief device 30 may also be installed on the cover plate 20.

[0054] In some embodiments, the housing 10 includes a plurality of connecting walls 11 and a mounting wall 12, wherein the plurality of connecting walls 11 are respectively a first connecting wall 11a, a second connecting wall 11b, a third connecting wall 11c, a fourth connecting wall 11d, and a fifth connecting wall 11e. In the Z-axis direction, the second connecting wall 11b, the third connecting wall 11c, the fourth connecting wall 11d, and the fifth connecting wall 11e are all fixedly connected to one side of the first connecting wall 11a. In the X-axis direction, the second connecting wall 11b and the third connecting wall 11c are spaced apart and arranged oppositely. In the Y-axis direction, the fourth connecting wall 11d and the fifth connecting wall 11e are spaced apart and arranged oppositely. The fourth connecting wall 11d and the fifth connecting wall 11e are both fixedly connected between the second connecting wall 11b and the third connecting wall 11c.

[0055] The mounting wall 12 is annular. In the Z-axis direction, the mounting wall 12 is fixedly connected to one side of the second connecting wall 11b, the third connecting wall 11c, the fourth connecting wall 11d and the fifth connecting wall 11e and faces away from the first connecting wall 11a. Specifically, the mounting wall 12 includes two first frames 121 and two second frames 122. In the Y-axis direction, the two first frames 121 are arranged opposite to each other, and in the X-axis direction, the two second frames 122 are arranged opposite to each other. In the Z-axis direction, the two first frames 121 are respectively fixedly connected to one side of the fourth connecting wall 11d and the fifth connecting wall 11e and face away from the first connecting wall 11a, and the two second frames 122 are respectively fixedly connected to one side of the second connecting wall 11b and the third connecting wall 11c and face away from the first connecting wall 11a, and the two second frames 122 are both fixedly connected between the two first frames 121.

[0056] The mounting wall 12 is provided with a plurality of first threaded holes 1211 and a plurality of second threaded holes 1221, a portion of the first threaded holes 1211 and another portion of the first threaded holes 1211 are respectively provided on two first frames 121, and the plurality of first threaded holes 1211 on each first frame 121 are arranged at intervals along the X-axis direction. A portion of the second threaded holes 1221 and another portion of the second threaded holes 1221 are respectively provided on two second frames 122, and the plurality of second threaded holes 1221 on each second frame 122 are arranged at intervals along the Y-axis direction.

[0057] Among them, the first connecting wall 11a, the second connecting wall 11b, the third connecting wall 11c, the fourth connecting wall 11d and the fifth connecting wall 11e enclose a receiving cavity 13. That is to say, the housing 10 is provided with a receiving cavity 13, and the receiving cavity 13 has an opening. The receiving cavity 13 includes the first connecting wall 11a, the second connecting wall 11b, the third connecting wall 11c, the fourth connecting wall 11d and the fifth connecting wall 11e. The installation wall 12 surrounds the opening of the receiving cavity 13. The projection of the installation wall 12 in the Z-axis direction is spaced apart from the projection of the receiving cavity 13 in the Z-axis direction. In some other embodiments, the installation wall 12 may also be omitted.

[0058] like Figure 3 and Figure 4 As shown, in some embodiments, the box body 100 is provided with an explosion relief hole 111, and the explosion relief hole 111 is provided in the shell body 10. Specifically, the explosion relief hole 111 is provided in the connecting wall 11. The explosion relief hole 111 penetrates the connecting wall 11 along the thickness direction of the connecting wall 11. The explosion relief hole 111 is provided in the second connecting wall 11b, and the explosion relief hole 111 penetrates the second connecting wall 11b along the X-axis direction. The explosion relief hole 111 is connected to the receiving cavity 13, and the receiving cavity 13 is exposed from the explosion relief hole 111 on the side of the second connecting wall 11b facing away from the receiving cavity 13. It can be understood that the receiving cavity 13 is exposed from the explosion relief hole 111 to the outside of the box body 100.

[0059] Exemplarily, the number of explosion-relief holes 111 is multiple. Specifically, the number of explosion-relief holes 111 is 4. In some other embodiments, the number of explosion-relief holes 111 can be 1, 2, 3, 5 or more. The number of explosion-relief holes 111 depends on the explosion-relief pressure in the box 100. The greater the explosion-relief pressure, the greater the number of explosion-relief holes 111. In the Y-axis direction, the multiple explosion-relief holes 111 are arranged at intervals. In some other embodiments, the multiple explosion-relief holes 111 can also be arranged at intervals in the Z-axis direction. In some other embodiments, the explosion-relief holes 111 can also be arranged on the first connecting wall 11a, the third connecting wall 11c, the fourth connecting wall 11d or the fifth connecting wall 11e.

[0060] like Figure 2 , Figure 3 and Figure 4 As shown, in some embodiments, by means including but not limited to threaded connection or welding, in the Z-axis direction, the cover plate 20 is fixedly stacked on one side of the mounting wall 12 and faces away from the first connecting wall 11a, and the projection of the cover plate 20 in the Z-axis direction covers the projection of the receiving cavity 13 in the Z-axis direction. It can be understood that the cover plate 20 covers the opening of the receiving cavity 13 and closes the receiving cavity 13.

[0061] Exemplarily, the power conversion device 1000 includes a plurality of fasteners 300. In this embodiment, the fasteners 300 are screws, and in other embodiments, the fasteners 300 may also be bolts. The cover plate 20 is fixedly stacked on one side of the installation wall 12 and faces away from the first connecting wall 11a by the plurality of fasteners 300.

[0062] Specifically, the cover plate 20 is provided with a plurality of third threaded holes 224 and a plurality of fourth threaded holes 225, and the plurality of third threaded holes 224 and the plurality of fourth threaded holes 225 are provided at the edge of the cover plate 20. In the Y-axis direction, a portion of the third threaded holes 224 is arranged at intervals with another portion of the third threaded holes 224. In the X-axis direction, a portion of the fourth threaded holes 225 is arranged at intervals with another portion of the fourth threaded holes 225. In the Z-axis direction, the plurality of third threaded holes 224 are opposite to the plurality of first threaded holes 1211 in one-to-one correspondence, and the plurality of fourth threaded holes 225 are opposite to the plurality of second threaded holes 1221 in one-to-one correspondence.

[0063] In this embodiment, each fastener 300 includes a head 301 and a threaded portion 302. The plurality of fasteners 300 include a plurality of first fasteners 300a and a plurality of second fasteners 300b. In this embodiment, the number of the first fasteners 300a is 10, and the number of the second fasteners 300b is 4. In other embodiments, the number of the first fasteners 300a may be 2, 3, 4, 5, 6, 7, 8, 9, 11 or more, and the number of the second fasteners 300b may be 1, 2, 3, 5 or more.

[0064] like Figure 2 and Figure 3 As shown, the threaded portions 302 of the plurality of first fasteners 300a are correspondingly installed in the plurality of third threaded holes 224 and the plurality of first threaded holes 1211, and the heads 301 of the plurality of first fasteners 300a are all against the side of the cover plate 20 facing away from the housing 10. It can be understood that the plurality of first fasteners 300a respectively fix the cover plate 20 to the two first frames 121, and the plurality of first fasteners 300a located in the first frame 121 are arranged at intervals along the length direction (X-axis direction) of the first frame 121. The threaded portions 302 of the multiple second fasteners 300b are installed in the multiple fourth threaded holes 225 and the multiple second threaded holes 1221 one by one, and the heads 301 of the multiple second fasteners 300b abut the side of the cover 20 facing away from the shell 10. It can be understood that the multiple second fasteners 300b fix the cover 20 to the two second frames 122 respectively, and the multiple second fasteners 300b located on the second frame 122 are spaced apart along the length direction (Y-axis direction) of the second frame 122.

[0065] Among them, the spacing between two adjacent first fasteners 300a among the multiple first fasteners 300a located on the first frame 121 is smaller than the spacing between two adjacent second fasteners 300b among the multiple second fasteners 300b located on the second frame 122, and the diameter of the head of the first fastener 300a is equal to the diameter of the head of the second fastener 300b, so that the contact area between the head of the first fastener 300a and the cover plate 20 is equal to the contact area between the head of the second fastener 300b and the cover plate 20, and thus the fastening force of the first fastener 300a on the cover plate 20 is equal to the fastening force of the second fastener 300b on the cover plate 20.

[0066] In some other embodiments, the diameter of the head of the first fastener 300a is larger than the diameter of the head of the second fastener 300b, so that the contact area between the head of the first fastener 300a and the cover plate 20 is larger than the contact area between the head of the second fastener 300b and the cover plate 20, and thus the fastening force of the first fastener 300a on the cover plate 20 is greater than the fastening force of the second fastener 300b on the cover plate 20.

[0067] like Figure 5 , Figure 6 and Figure 7 As shown, in some embodiments, the cover plate 20 includes a central portion 21 and an edge portion 22 , and the edge portion 22 is disposed outside the central portion 21 . Figure 5The dotted frame shown in the figure is the boundary between the center portion 21 and the edge portion 22. The projection of the center portion 21 in the Z-axis direction overlaps with the projection of the receiving cavity 13 in the Z-axis direction. The projection of the edge portion 22 in the Z-axis direction overlaps with the projection of the receiving cavity 13 in the Z-axis direction.

[0068] The center portion 21 includes a first surface 211 and a second surface 212. In the Z-axis direction, the first surface 211 faces the receiving cavity 13, and the second surface 212 faces away from the receiving cavity 13. The edge portion 22 includes a third surface 221 and a fourth surface 222. In the Z-axis direction, the third surface 221 faces the receiving cavity 13, and the fourth surface 222 faces away from the receiving cavity 13. The first surface 211 and the third surface 221 are flush. In some other embodiments, the first surface 211 and the third surface 221 may not be flush.

[0069] In some embodiments, the cover plate 20 is provided with an explosion relief groove 223. By means including but not limited to laser processing, machining or chemical etching, in the Z-axis direction, the explosion relief groove 223 is arranged on one side of the edge portion 22. Specifically, the explosion relief groove 223 is arranged on one side of the third surface 221 of the edge portion 22 and faces away from the fourth surface 222, and the explosion relief groove 223 is connected to the receiving cavity 13. That is, in the Z-axis direction, the surface of the cover plate 20 facing the circuit board 200 includes the explosion relief groove 223. In some other embodiments, the explosion relief groove 223 can also be arranged on the first surface 211 of the center portion 21, or a part of the explosion relief groove 223 is arranged on the first surface 211 of the center portion 21, and the other part is arranged on the third surface 221 of the edge portion 22.

[0070] Exemplarily, the explosion relief groove 223 is in a straight line shape. In some other embodiments, the explosion relief groove 223 may also be in a curved, circular, elliptical or other special-shaped structure. The depth of the explosion relief groove 223 (i.e., the dimension of the explosion relief groove 223 in the Z-axis direction) is less than the thickness of the cover plate 20 (i.e., the dimension of the cover plate 20 in the Z-axis direction). Preferably, the depth of the explosion relief groove 223 (i.e., the dimension of the explosion relief groove 223 in the Z-axis direction) is less than or equal to half of the thickness of the cover plate 20 (i.e., the dimension of the cover plate 20 in the Z-axis direction), and the width of the explosion relief groove 223 is less than or equal to 2 mm. The depth and width of the explosion relief groove 223 are set within this range, which ensures that the cover plate 20 has a certain structural strength while meeting the explosion relief requirements, and prevents the cover plate 20 from being easily deformed during normal use. In some other embodiments, in the Z-axis direction, the depth of the explosion-venting groove 223 (i.e., the size of the explosion-venting groove 223 in the Z-axis direction) may also be greater than half the thickness of the cover plate 20 (i.e., the size of the cover plate 20 in the Z-axis direction), and the width of the explosion-venting groove 223 may also be greater than 2 mm.

[0071] Exemplarily, there are multiple explosion venting grooves 223. In this embodiment, the number of explosion venting grooves 223 is 4. In other embodiments, the number of explosion venting grooves 223 may also be 1, 2, 3, 5 or more. The 4 explosion venting grooves 223 are arranged at intervals around the central portion 21. Among the 4 explosion venting grooves 223, each explosion venting groove 223 is arranged on the diagonal of the cover plate 20, and each explosion venting groove 223 extends along the diagonal of the cover plate 20. Specifically, two explosion venting grooves 223 are arranged on a diagonal of the cover plate 20, and the two explosion venting grooves 223 are arranged at intervals in the extension direction of the diagonal. Another two explosion venting grooves 223 are arranged on another diagonal of the cover plate 20, and the other two explosion venting grooves 223 are arranged at intervals in the extension direction of the diagonal.

[0072] In some embodiments, Figure 7 As shown, the circuit board 200 is accommodated in the receiving chamber 13. When the circuit board 200 is working, the film in the capacitor 202 will generate combustible gas, causing the air pressure in the receiving chamber 13 to rise. It can be understood that in the power conversion device 1000 provided in the embodiment of the present application, the explosion relief groove 223 is provided on the cover plate 20 to weaken the local structural strength of the cover plate 20. When the air pressure in the receiving chamber 13 rises sharply, the gas pressure acts on the cover plate 20, so that the cover plate 20 is deformed toward the positive direction of the Z axis at the position where the explosion relief groove 223 is provided, thereby realizing directional deformation of the cover plate 20. After the cover plate 20 is deformed, the space of the receiving chamber 13 becomes larger, and the air pressure in the receiving chamber 13 becomes smaller as the space of the receiving chamber 13 becomes larger, preventing the cover plate 20 from being separated from the housing 10 due to excessive air pressure in the receiving chamber 13, avoiding the situation where the cover plate 20 pops out and injures people, thereby improving the use safety of the power conversion device 1000. At the same time, after the cover plate 20 is deformed, the staff can easily find that the power conversion device 1000 is abnormal, and the staff can cut off the power supply of the power conversion device 1000 in time to prevent the power conversion device 1000 from continuing to work and causing the air pressure to continue to increase.

[0073] In addition, when the air pressure in the receiving chamber 13 is too high, the cover plate 20 bursts at the corresponding position of the explosion relief groove 223 to form a gap, and the combustible gas can be discharged from the gap to the outside of the box body 100, thereby preventing the air pressure in the receiving chamber 13 from continuing to increase and causing the cover plate 20 and the shell 10 to separate. At the same time, it can also prevent the power conversion device 1000 from exploding due to excessive combustible gas in the receiving chamber 13.

[0074] Since the spacing between two adjacent first fasteners 300a among the multiple first fasteners 300a located on the first frame 121 is smaller than the spacing between two adjacent second fasteners 300b among the multiple second fasteners 300b located on the second frame 122, and the fastening force of the first fastener 300a on the cover plate 20 is greater than or equal to the fastening force of the second fastener 300b on the cover plate 20, the fastening force between the cover plate 20 and the second frame 122 is smaller than the fastening force between the cover plate 20 and the first frame 121. Furthermore, when the air pressure in the receiving chamber 13 is too high, the multiple second fasteners 300b located on the second frame 122 will loosen, and a gap will appear between the cover 20 and the second frame 122. The combustible gas in the receiving chamber 13 can be discharged from the gap to the outside of the box body 100, so that the air pressure in the receiving chamber 13 is reduced, preventing the cover 20 and the shell body 10 from separating due to the excessive air pressure in the receiving chamber 13, avoiding the cover 20 from popping out and injuring people, and preventing the combustible gas in the receiving chamber 13 from exploding, thereby improving the safety of the power conversion device 1000.

[0075] A plurality of explosion relief grooves 223 are arranged on the edge portion 22, and the plurality of explosion relief grooves 223 are arranged at intervals from each other. When the gas pressure acts on the center portion 21 and the edge portion 22, the center portion 21 bulges toward the positive direction of the Z axis, and the edge portion 22 is deformed under the action of the gas pressure and the tension of the center portion 21, and one end of the edge portion 22 facing the center portion 21 is tilted toward the positive direction of the Z axis, and the entire cover plate 20 is disc-shaped. The height of the bulge of the center portion 21 depends on the tilting angle of the edge portion 22. In the present embodiment, a plurality of explosion relief grooves 223 are arranged at intervals on the edge portion 22, which is beneficial to weakening the structural strength of the edge portion 22. The edge portion 22 is more easily deformed under the action of air pressure and the tension of the center portion 21, and the warping angle of the edge portion 22 is larger, so that the height of the protrusion of the center portion 21 is higher, and then the space of the receiving chamber 13 becomes larger, so as to reduce the air pressure in the receiving chamber 13 to a greater extent, prevent the cover plate 20 from being separated from the shell 10 due to excessive air pressure in the receiving chamber 13, avoid the cover plate 20 from popping out and injuring people, and the power conversion device 1000 is safer to use.

[0076] When the cover plate 20 bulges in the positive direction of the Z axis, the deformation of the cover plate 20 in the diagonal area is the largest. Therefore, each of the multiple explosion relief grooves 223 is arranged on the diagonal of the cover plate 20, and each explosion relief groove 223 extends along the diagonal of the cover plate 20, which is conducive to weakening the structural strength of the cover plate 20 in the diagonal area. When the air pressure in the receiving chamber 13 is too high, the cover plate 20 is more easily deformed in the diagonal area, and the deformation of the cover plate 20 in the diagonal area is greater, so that the height of the cover plate 20 is higher, and then the space of the receiving chamber 13 becomes larger, so as to reduce the air pressure in the receiving chamber 13 to a greater extent, prevent the cover plate 20 from separating from the housing 10 due to excessive air pressure in the receiving chamber 13, avoid the cover plate 20 popping out and injuring people, and the power conversion device 1000 is safer to use.

[0077] Please refer to Figure 8 , and combined with Figure 2 . Figure 8 yes Figure 2 The structure diagram of the cover plate 20 of the power conversion device 1000 in another embodiment is shown.

[0078] like Figure 8 As shown, in some embodiments, multiple explosion venting grooves 223 can also be arranged in a straight line, and multiple explosion venting grooves 223 are arranged at intervals from each other. Exemplarily, the number of explosion venting grooves 223 is 4, and in some other embodiments, the number of explosion venting grooves 223 can also be 1, 2, 3, 5 or more. Multiple explosion venting grooves 223 are arranged at intervals along the X-axis direction, and each explosion venting groove 223 extends along the Y-axis direction. In some other embodiments, multiple explosion venting grooves 223 are arranged at intervals along the Y-axis direction, and each explosion venting groove 223 extends along the X-axis direction. Alternatively, multiple explosion venting grooves 223 can also be arranged at intervals along the diagonal of the cover plate 20.

[0079] It can be understood that the design of arranging multiple explosion-proof grooves 223 in a straight line is conducive to improving the coverage of the explosion-proof grooves 223 on the cover plate 20. When the cover plate 20 is subjected to the gas pressure in the receiving chamber 13, the deformation of the cover plate 20 is greater, and then the space of the receiving chamber 13 becomes larger, and the air pressure drop in the receiving chamber 13 is smaller, thereby preventing the cover plate 20 from being separated from the shell 10 due to excessive air pressure in the receiving chamber 13, avoiding the cover plate 20 from popping out and injuring people, and the power conversion device 1000 is safer.

[0080] Please refer to Fig. 9 , and combined with Figure 2 . Fig. 9 yes Figure 2 The structure diagram of the cover plate 20 of the power conversion device 1000 in another embodiment is shown.

[0081] like Fig. 9As shown, in some embodiments, multiple explosion relief grooves 223 are arranged crosswise with each other, and multiple explosion relief grooves 223 are interconnected. Exemplarily, in this embodiment, the number of explosion relief grooves is 2, and in some other embodiments, the number of explosion relief grooves 223 can also be 1, 3, 4, 5 or more. Two explosion relief grooves 223 are respectively arranged on two diagonal lines of the cover plate 20, and the two explosion relief grooves 223 extend along the two diagonal lines of the cover plate 20 respectively. The two explosion relief grooves 223 are arranged crosswise with each other, and the two explosion relief grooves are interconnected.

[0082] It can be understood that the multiple explosion relief grooves 223 are arranged crosswise and the multiple explosion relief grooves 223 are interconnected, which is conducive to weakening the structural strength of the cover plate 20 at the intersection of the multiple explosion relief grooves 223. When the air pressure in the receiving chamber 13 is too high, the cover plate 20 can burst at the intersection of the explosion relief grooves 223 to form a gap, and the combustible gas in the receiving chamber 13 can be discharged from the gap to the outside of the box body 100, and the air pressure in the receiving chamber 13 becomes smaller, preventing the cover plate 20 from separating from the shell 10 due to the excessive air pressure in the receiving chamber 13, avoiding the cover plate 20 from popping out and injuring people, and the power conversion device 1000 is safer. At the same time, it is conducive to preventing the power conversion device 1000 from exploding due to excessive combustible gas in the receiving chamber 13.

[0083] Please refer to Fig.10 , and combined with Figure 2 . Fig.10 yes Figure 2 The structure diagram of the cover plate 20 of the power conversion device 1000 in another embodiment is shown.

[0084] like Fig.10 As shown, in some embodiments, a plurality of explosion venting grooves 223 are arranged in a ring shape, and the plurality of explosion venting grooves 223 are evenly spaced from each other. Exemplarily, in this embodiment, the number of explosion venting grooves 223 is 8, and in some other embodiments, the number of explosion venting grooves 223 may also be 2, 3, 4, 5, 6, 7, 9 or more. A plurality of explosion venting grooves 223 are arranged in a ring shape around the center of the cover plate 20, and the plurality of explosion venting grooves 223 are evenly spaced from each other. In the direction from the center of the cover plate 20 to the edge of the cover plate 20, the spacing between two adjacent explosion venting grooves 223 gradually increases among the plurality of explosion venting grooves 223.

[0085] It can be understood that the multiple explosion-proof grooves 223 are arranged in a ring shape. The design of the multiple explosion-proof grooves 223 being evenly spaced from each other is conducive to improving the uniformity of the deformation of the cover plate 20, and is conducive to increasing the deformation amount of the cover plate 20, thereby making the space of the receiving chamber 13 larger, and the air pressure in the receiving chamber 13 smaller, preventing the cover plate 20 from separating from the shell 10 due to excessive air pressure in the receiving chamber 13, avoiding the cover plate 20 from popping out and injuring people, and the power conversion device 1000 is safer.

[0086] Please refer to Fig.11 , and combined with Figure 3 , Fig.11 It is a schematic diagram of the three-dimensional structure of a power conversion device 1000 provided in another embodiment of the present application at another angle.

[0087] like Figure 3 and Fig.11 As shown, in some embodiments, the fastener 300 includes a plurality of third fasteners 300c and at least two fourth fasteners 300d. In this embodiment, the number of the third fasteners 300c is 10, and the number of the fourth fasteners 300d is 2. In other embodiments, the number of the third fasteners 300c may be 2, 3, 4, 5, 6, 7, 8, 9, 11 or more, and the number of the fourth fasteners 300d may be 3, 4, 5 or more.

[0088] Multiple third fasteners 300c fix the cover plate 20 to the two first frames 121 respectively. The multiple third fasteners 300c located on the first frame 121 are arranged at intervals along the length direction (X-axis direction) of the first frame 121, and the heads 301 of the multiple third fasteners 300c are all abutted against the side of the cover plate 20 facing away from the shell 10.

[0089] One of the fourth fasteners 300d is fixedly connected to the cover plate 20 and one of the second frames 122, and the other fourth fastener 300d is fixedly connected to the cover plate 20 and the other second frame 122, and the heads 301 of the two fourth fasteners 300d are in contact with the side of the cover plate 20 facing away from the housing 10. The matching relationship between the third fastener 300c and the cover plate 20 and the first frame 121 is specifically referred to the relevant description of the first fastener 300a, and the matching relationship between the fourth fastener 300d and the cover plate 20 and the second frame 122 is specifically referred to the relevant description of the second fastener 300b, which will not be repeated.

[0090] The spacing between the third fastener 300c and the fourth fastener 300d adjacent to the third fastener 300c is greater than or equal to the spacing between two adjacent third fasteners 300c among the plurality of third fasteners 300c located on the first frame 121. The diameter of the head 301 of the third fastener 300c is greater than the diameter of the head of the fourth fastener 300d, so that the contact area between the head of the third fastener 300c and the cover plate 20 is greater than the contact area between the head of the fourth fastener 300d and the cover plate 20, and thus the fastening force of the third fastener 300c on the cover plate 20 is greater than the fastening force of the fourth fastener 300d on the cover plate 20.

[0091] Since the fastening force of the fourth fastener 300d on the cover 20 is relatively small, when the air pressure in the receiving chamber 13 is too high, the fourth fastener 300d will loosen, and a gap will appear between the cover 20 and the second frame 122. The combustible gas in the receiving chamber 13 can be discharged from the gap to the outside of the box body 100, so that the air pressure in the receiving chamber 13 is reduced, preventing the cover 20 and the shell body 10 from separating due to the excessive air pressure in the receiving chamber 13, avoiding the cover 20 from popping out and injuring people, and preventing the combustible gas in the receiving chamber 13 from exploding, thereby improving the safety of the power conversion device 1000.

[0092] By setting the abutment area between the third fastener 300c and the cover plate 20 to be larger than the abutment area between the fourth fastener 300d and the cover plate 20, the fastening force of the third fastener 300c on the cover plate 20 is larger than the fastening force of the fourth fastener 300d on the cover plate 20, which has a simple structure and low cost.

[0093] In some other embodiments, the diameter of the threaded portion 302 of the third fastener 300c is greater than the diameter of the threaded portion 302 of the fourth fastener 300d. This design can also make the fastening force of the third fastener 300c on the cover plate 20 greater than the fastening force of the fourth fastener 300d on the cover plate 20.

[0094] Please refer to Fig.12 , and combined with Figure 3 , Fig.12 It is a schematic diagram of the three-dimensional structure of a power conversion device 1000 provided in another embodiment of the present application at another angle.

[0095] like Figure 3 and Fig.12 As shown, in some embodiments, the power conversion device 1000 includes a plurality of gaskets 400, and the plurality of gaskets 400 include a plurality of first gaskets 400a and a plurality of second gaskets 400b. In this embodiment, the number of the first gaskets 400a is 10, and the number of the second gaskets 400b is 2. In some other embodiments, the number of the first gaskets 400a may be 2, 3, 4, 5, 6, 7, 8, 9, 11 or more, and the number of the second gaskets 400b may be 3, 4, 5 or more.

[0096] The plurality of first gaskets 400a are disposed one by one between the heads of the plurality of third fasteners 300c and the cover plate 20, the plurality of first gaskets 400a abut against the side of the cover plate 20 away from the housing 10, and the heads 301 of the plurality of third fasteners 300c abut against the side of the plurality of first gaskets 400a away from the cover plate 20. The plurality of second gaskets 400b are disposed one by one between the heads of the plurality of fourth fasteners 300d and the cover plate 20, the plurality of second gaskets 400b abut against the side of the cover plate 20 away from the housing 10, and the heads 301 of the plurality of fourth fasteners 300d abut against the side of the plurality of second gaskets 400b away from the cover plate 20. Among them, the diameter of each first gasket 400a is greater than the diameter of each second gasket 400b, so that the abutment area between the first gasket 400a and the cover plate 20 is greater than the abutment area between the second gasket 400b and the cover plate 20, and thus the fastening force of the third fastener 300c on the cover plate 20 is greater than the fastening force of the fourth fastener 300d on the cover plate 20.

[0097] Since the fastening force of the fourth fastener 300d on the cover 20 is relatively small, when the air pressure in the receiving chamber 13 is too high, the fourth fastener 300d will loosen, and a gap will appear between the cover 20 and the second frame 122. The combustible gas in the receiving chamber 13 can be discharged from the gap to the outside of the box body 100, preventing the combustible gas in the receiving chamber 13 from exploding due to excess.

[0098] Please refer to Fig.13 , Fig.14 , Fig.15 and Fig.16 , and combined with Figure 7 . Fig.13 yes Figure 7 An enlarged view of portion A of the power conversion device 1000 is shown. Fig.14 yes Figure 2 The explosion relief device 30 of the power conversion device 1000 is shown as a schematic three-dimensional structure at another angle. Fig.15 yes Fig.14 The explosion relief piece 32 of the explosion relief device 30 is shown as a three-dimensional structural schematic diagram at another angle. Fig.16 yes Fig.14 The explosion relief device 30 shown is a schematic structural diagram cut along the line L2-L2.

[0099] In some embodiments, Figure 7 and Fig.13 As shown, the explosion relief device 30 is installed on the housing 10, and the projection of the explosion relief device 30 in the axial direction of the explosion relief hole 111 covers the projection of the explosion relief hole 111 in its axial direction. The explosion relief device 30 blocks the explosion relief hole 111 and closes the receiving cavity 13. Exemplarily, the number of the explosion relief devices 30 is 4. Multiple explosion relief devices 30 cover multiple explosion relief holes 111 and close the receiving cavity 13 one by one.

[0100] like Fig.13 , Fig.14 and Fig.15 As shown, the explosion relief device 30 includes a protective cover 31 and an explosion relief sheet 32. The explosion relief sheet 32 ​​is received in the protective cover 31. In the X-axis direction, one end of the protective cover 31 penetrates into the explosion relief hole 111 and is installed in the explosion relief hole 111. The protective cover 31 and the explosion relief sheet 32 ​​jointly shield the explosion relief hole 111 and close the receiving cavity 13.

[0101] like Fig.13 , Fig.14 and Fig.16 As shown, in some embodiments, the protective cover 31 includes a cylinder 311 and a shielding portion 312, and the shielding portion 312 is arranged on one side of the cylinder 311 in the axial direction of the cylinder 311. Among them, by means including but not limited to bonding, welding or threaded connection, one end of the cylinder 311 away from the shielding portion 312 is inserted into the explosion-proof hole 111, and the outer circumferential surface of the cylinder 311 is fitted and fixed to the inner circumferential surface of the explosion-proof hole 111. In the X-axis direction, the shielding portion 312 is located on the side of the cylinder 311 facing away from the receiving chamber 13. That is to say, in the axial direction of the cylinder 311, the shielding portion 312 is arranged on one side of the cylinder 311 and facing away from the receiving chamber 13.

[0102] In some embodiments, the cylinder 311 is provided with a mounting hole 3111, and the mounting hole 3111 penetrates the cylinder 311 along the axial direction of the cylinder 311. The projection of the shielding portion 312 in the axial direction of the cylinder 311 covers the projection of the mounting hole 3111 in the axial direction of the cylinder 311. The mounting hole 3111 is communicated with the receiving cavity 13.

[0103] In some embodiments, the shielding portion 312 is provided with a through hole 3121, and the through hole 3121 penetrates the shielding portion 312 along the axial direction of the cylinder 311, and the through hole 3121 is connected with the mounting hole 3111. There are multiple through holes 3121, specifically, there are 7 through holes 3121, and the 7 through holes 3121 are distributed at intervals in the shielding portion 312. In some other embodiments, the number of through holes 3121 may also be 1. The through hole 3121 is connected with the mounting hole 3111. That is to say, in the axial direction of the cylinder 311, the receiving cavity 13, the mounting hole 3111 and the through hole 3121 are connected in sequence.

[0104] like Fig.13 , Fig.15 and Fig.16As shown, illustratively, the explosion venting piece 32 is circular. In some other embodiments, the explosion venting piece 32 may be triangular, square, elliptical or other special-shaped structures. The explosion venting piece 32 is fixed in the mounting hole 3111 of the cylinder 311 by means including but not limited to welding or bonding, and the outer peripheral surface of the explosion venting piece 32 is fitted and fixed to the inner peripheral surface of the mounting hole 3111. In the thickness direction of the explosion venting piece 32, the explosion venting piece 32 is spaced and arranged opposite to the shielding portion 312, the explosion venting piece 32 is exposed to the outside of the protective cover 31 from the through hole 3121, and the explosion venting piece 32 is opposite to the receiving cavity 13.

[0105] It can be understood that the cylinder 311 is sleeved on the outside of the explosion-relief plate 32, and the cylinder 311 and the explosion-relief plate 32 jointly block the explosion-relief hole 111 and close the receiving chamber 13. When the air pressure in the receiving chamber 13 is too high, the gas pressure acts on the explosion-relief plate 32, and the explosion-relief plate 32 is broken by force, and the gas in the receiving chamber 13 is discharged from the rupture of the explosion-relief plate 32, so as to prevent the explosion caused by excessive air pressure in the receiving chamber 13. The embodiment of the present application sets the explosion-relief device 30 to cooperate with the explosion-relief groove 223 for explosion relief, and has higher safety performance. And the explosion-relief device 30 of this embodiment is simpler in structure and lower in cost than the valve-type explosion-relief device 30 by setting the explosion-relief plate 32 to break and release pressure.

[0106] By setting the protective cover 31, the explosion-proof plate 32 is installed in the explosion-proof hole 111 through the cylinder 311 of the protective cover 31, so as to avoid the explosion-proof plate 32 from being damaged due to improper operation when the explosion-proof device 30 is installed in the explosion-proof hole 111, which is conducive to reducing the difficulty of assembly and improving the assembly efficiency. The design of the shielding part 312 is conducive to improving the structural stability of the cylinder 311 and the structural stability of the protective cover 31, and can prevent the explosion-proof plate 32 from colliding with the outside world, avoiding the damage of the explosion-proof plate 32, and helping to improve the product life. In addition, the design of the through hole 3121 ensures that the gas in the receiving chamber 13 can be discharged to the outside of the box body 100 through the explosion-proof plate 32 and the shielding part 312, so as to reduce the air pressure in the receiving chamber 13, prevent the cover plate 20 from being separated from the shell 10 due to the excessive air pressure in the receiving chamber 13, and avoid the cover plate 20 from popping out and injuring people, so that the power conversion device 1000 is safer to use.

[0107] like Fig.13 , Fig.14 and Fig.15As shown, in some embodiments, the explosion venting piece 32 is provided with a first notch 321 and a second notch 322 by means including but not limited to laser processing, machining or chemical corrosion, and the first notch 321 and the second notch 322 are both linear. In some other embodiments, the first notch 321 and the second notch 322 may also be arc-shaped, V-shaped, triangular, elliptical or other special-shaped structures. In the thickness direction of the explosion venting piece 32, the first notch 321 is provided on one side of the explosion venting piece 32, and the second notch 322 is provided on one side of the explosion venting piece 32 and close to the first notch 321. In the thickness direction of the explosion venting piece 32, the first notch 321 and the second notch 322 are both far away from the receiving cavity 13. That is to say, the first notch 321 and the second notch 322 are both arranged on the side of the explosion venting piece 32 facing away from the receiving cavity 13. In some other embodiments, the first notch 321 and the second notch 322 may also be arranged on the side of the explosion venting piece 32 facing the receiving cavity 13, and the first notch 321 and the second notch 322 may also be close to the receiving cavity 13.

[0108] In the radial direction of the explosion venting piece 32, the first notch 321 penetrates the explosion venting piece 32 in the radial direction of the explosion venting piece 32. The first notch 321 and the second notch 322 are arranged crosswise, and the first notch 321 is connected to the second notch 322. In the radial direction of the explosion venting piece 32, the second notch 322 does not penetrate the explosion venting piece 32. In some other embodiments, the first notch 321 may not penetrate the explosion venting piece 32, and the second notch 322 may penetrate the explosion venting piece 32 in the radial direction of the explosion venting piece 32. In the thickness direction of the explosion venting piece 32, the depth of the first notch 321 (i.e., the dimension of the first notch 321 along the thickness direction of the explosion venting piece 32) and the depth of the second notch 322 (i.e., the dimension of the second notch 322 along the thickness direction of the explosion venting piece 32) are both less than or equal to half of the thickness of the explosion venting piece 32 (i.e., the dimension of the explosion venting piece 32 along its thickness direction). The depth of the first notch 321 and the depth of the second notch 322 are set within this range, ensuring that the explosion venting sheet 32 ​​has a certain structural strength while meeting the explosion venting requirements, and preventing the explosion venting sheet 32 ​​from being easily broken during normal use. In some other embodiments, the depth of the first notch 321 (i.e., the dimension of the first notch 321 along the thickness direction of the explosion venting sheet 32) and the depth of the second notch 322 (i.e., the dimension of the second notch 322 along the thickness direction of the explosion venting sheet 32) are both greater than half of the thickness of the explosion venting sheet 32 ​​(i.e., the dimension of the explosion venting sheet 32 ​​along its thickness direction).

[0109] In this embodiment, the first notch 321 is provided to weaken the local structural strength of the explosion venting plate 32. When the gas pressure acts on the explosion venting plate 32, the explosion venting plate 32 will rupture a small opening at the first notch 321, and the gas flows out of the box body 100 from the small opening. In the process of the gas flowing through the small opening, the pressure relief pressure continuously acts on the small opening, and the diameter of the small opening continuously increases, so that the entire explosion venting plate 32 ruptures.

[0110] It can be understood that the first notch 321 serves to guide the explosion-proof plate 32 to rupture, so that when the air pressure in the receiving chamber 13 is too high, the explosion-proof plate 32 can rupture quickly, and the combustible gas can be discharged to the outside of the box body 100 more quickly, thereby avoiding the explosion of the power conversion device 1000, thereby improving the safety of the power conversion device 1000.

[0111] The first notch 321 penetrates the explosion venting piece 32 along the radial direction of the explosion venting piece 32, which is conducive to improving the bending performance of the explosion venting piece 32. When the explosion venting piece 32 is subjected to air pressure, it is easier to bend along the first notch 321, and the explosion venting piece 32 is more likely to break at the bending point after bending, so that the explosion venting piece 32 breaks faster. In addition, the length of the first notch 321 is longer, and the caliber of the explosion venting piece 32 breaking along the first notch 321 is larger, so that the combustible gas can be discharged to the outside of the box 100 faster, avoiding the explosion of the power conversion device 1000, and improving the use safety of the power conversion device 1000. The second notch 322 set on the explosion venting piece 32 is conducive to increasing the caliber of the explosion venting piece 32 breaking, and the combustible gas can be discharged to the outside of the box 100 faster, and the power conversion device 1000 has a faster pressure relief speed and higher use safety.

[0112] Please refer to Fig.17 and Fig.18 , and combined with Figure 2 and Fig.13 . Fig.17 yes Figure 2 The power conversion device 1000 shown is a schematic structural diagram of another embodiment cut along line L1 - L1 . Fig.18 yes Fig.17 An enlarged view of portion B of the power conversion device 1000 is shown.

[0113] In some embodiments, Figure 2 , Fig.17 and Fig.18 As shown, the explosion relief device 30 only includes the explosion relief sheet 32. In other words, the protective cover 31 (such as Fig.13 The explosion venting piece 32 is received in the explosion venting hole 111 by means including but not limited to bonding or welding, and the outer peripheral surface of the explosion venting piece 32 is fixed to the inner peripheral surface of the explosion venting hole 111, and the explosion venting piece 32 blocks the explosion venting hole 111 and closes the receiving cavity 13. In this embodiment, the explosion venting piece 32 is received in the explosion venting hole 111 to prevent the explosion venting piece 32 from being damaged by collision with the outside world, which is conducive to improving the life of the product.

[0114] See also Fig.19 and Fig. 20 , Fig.19 yes Figure 2 The power conversion device 1000 shown is a schematic structural diagram of another embodiment cut along line L1 - L1 . Fig. 20 yes Fig.19 An enlarged view of portion C of the power conversion device 1000 is shown.

[0115] like Fig.19 and Fig. 20 As shown, in some other embodiments, a fixing hole 112 is provided on the side of the connecting wall 11 away from the receiving cavity 13, and in some other embodiments, the fixing hole 112 can also be provided on the side of the connecting wall 11 facing the receiving cavity 13. The fixing hole 112 is connected to the explosion-relief hole 111. Among them, the projection of the fixing hole 112 in the axial direction of the explosion-relief hole 111 covers the projection of the explosion-relief hole 111 in its axial direction. That is, the aperture of the fixing hole 112 is larger than the aperture of the explosion-relief hole 111, and there is a step surface 113 between the fixing hole 112 and the explosion-relief hole 111. By means including but not limited to bonding or welding, the explosion-relief sheet 32 ​​is fixedly connected to the step surface 113 on one side along the thickness direction thereof, and the explosion-relief sheet 32 ​​blocks the explosion-relief hole 111 and closes the receiving cavity 13. It can be understood that the explosion-relief sheet 32 ​​is stacked on one side of the connecting wall 11 along the thickness direction thereof, and the projection of the explosion-relief sheet 32 ​​in the thickness direction of the connecting wall 11 covers the projection of the explosion-relief hole 111 in the thickness direction of the connecting wall 11. This design method of only providing the explosion relief sheet 32 ​​to cover the explosion relief hole 111 is simple in structure and low in cost. In other embodiments, the fixing hole 112 may also be omitted. The explosion relief sheet 32 ​​is fixedly stacked on the surface of the connecting wall 11 and faces away from the receiving cavity 13.

[0116] The explosion-venting piece 32 is stacked with the connecting wall 11. The projection of the explosion-venting piece 32 in the thickness direction of the connecting wall 11 covers the projection of the explosion-venting hole 111 in the thickness direction of the connecting wall 11. While ensuring that the explosion-venting piece 32 can cover the explosion-venting hole 111 and close the accommodating cavity 13, it is not only simple in structure, but also helps to reduce the difficulty of assembling the explosion-venting piece 32 and the connecting wall 11, facilitates assembly, improves assembly efficiency, and reduces processing costs.

[0117] See also Fig.21 , Fig. 22 and Fig.23 , and combined with Fig.13 , Fig.21 It is a schematic diagram of the three-dimensional structure of a power conversion device 1000 provided in another embodiment of the present application at another angle. Fig. 22 yes Fig.21 The power conversion device 1000 shown is a schematic structural diagram cut along the line L3-L3. Fig.23 yes Fig. 22 An enlarged view of portion D of the power conversion device 1000 is shown.

[0118] like Fig.21 , Fig. 22 and Fig.23As shown, in some other embodiments, the explosion venting hole 111 may also be provided on the cover plate 20, and the explosion venting hole 111 penetrates the cover plate 20 along the thickness direction (Z-axis direction) of the cover plate 20. In the Z-axis direction, the explosion venting sheet 32 ​​is stacked with the cover plate 20. Specifically, the explosion venting sheet 32 ​​is stacked on one side of the cover plate 20, and the projection of the explosion venting sheet 32 ​​in the axial direction (Z-axis direction) of the explosion venting hole 111 covers the projection of the explosion venting hole 111 in the axial direction (Z-axis direction) of the explosion venting hole 111. Specifically, the side of the cover plate 20 away from the receiving cavity 13 is provided with a fixing hole 112. In some other embodiments, the fixing hole 112 may also be provided on the side of the cover plate 20 facing the receiving cavity 13. The fixing hole 112 is connected to the explosion venting hole 111, and the projection of the fixing hole 112 in the axial direction of the explosion venting hole 111 covers the projection of the explosion venting hole 111 in its axial direction. That is, the aperture of the fixing hole 112 is larger than the aperture of the explosion-relief hole 111, and there is a step surface 113 between the fixing hole 112 and the explosion-relief hole 111. The explosion-relief sheet 32 ​​is fixedly connected to the step surface 113 along one side of its thickness direction by means including but not limited to bonding or welding, and the explosion-relief sheet 32 ​​blocks the explosion-relief hole 111 and closes the receiving cavity 13. The explosion-relief sheet 32 ​​is stacked on one side of the cover plate 20, and the projection of the explosion-relief sheet 32 ​​in the thickness direction of the cover plate 20 and the projection of the explosion-relief hole 111 in the thickness direction of the cover plate 20 are designed to not only have a simple structure, but also help reduce the difficulty of assembling the explosion-relief sheet 32 ​​and the cover plate 20, facilitate assembly, improve assembly efficiency, and reduce processing costs.

[0119] like Fig.13 , Fig. 22 and Fig.23 As shown, in other embodiments, the explosion relief device 30 includes a protective cover 31 and an explosion relief sheet 32, and the explosion relief sheet 32 ​​is received in the protective cover 31. In the thickness direction of the cover plate, one end of the protective cover 31 penetrates the explosion relief hole 111 and is installed in the explosion relief hole 111. The protective cover 31 and the explosion relief sheet 32 ​​jointly block the explosion relief hole 111 and close the receiving cavity 13. For details, please refer to Figure 2 Relevant description of the explosion relief device 30 of the illustrated embodiment.

[0120] The above are only some embodiments and implementation methods of the present application, and the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by any person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A power conversion device, characterized in that: The power conversion device comprises: A box body, the box body comprising a shell and a cover plate, the shell being provided with a receiving cavity, the receiving cavity having an opening, the cover plate covering the opening of the receiving cavity and closing the receiving cavity; and A circuit board, the circuit board is accommodated in the accommodation cavity, the circuit board is provided with a DC-AC conversion circuit and a capacitor, wherein the DC-AC conversion circuit is used to convert direct current from a photovoltaic module or an energy storage battery into alternating current; Wherein, the surface of the cover plate facing the circuit board includes a plurality of explosion relief grooves, and the depth of the explosion relief grooves is less than the thickness of the cover plate.

2. The power conversion device according to claim 1, characterized in that: The housing comprises two first frames and two second frames, the two first frames are arranged opposite to each other, the two second frames are arranged opposite to each other, and the two second frames are fixedly connected between the two first frames; The power conversion device comprises a plurality of first fasteners, wherein the plurality of first fasteners respectively fix the cover plate to the two first frames, wherein the plurality of first fasteners located on the first frame are arranged at intervals along the length direction of the first frame; The power conversion device comprises a plurality of second fasteners, and the plurality of second fasteners respectively fix the cover plate to the two second frames, wherein the plurality of second fasteners located on the second frame are arranged at intervals along the length direction of the second frame; A distance between two adjacent first fasteners among a plurality of first fasteners located on the first frame is smaller than a distance between two adjacent second fasteners among a plurality of second fasteners located on the second frame, and a fastening force of the first fastener on the cover plate is greater than or equal to a fastening force of the second fastener on the cover plate.

3. The power conversion device according to claim 1, characterized in that: The housing comprises two first frames and two second frames, the two first frames are arranged opposite to each other, the two second frames are arranged opposite to each other, and the two second frames are fixedly connected between the two first frames; The power conversion device comprises a plurality of third fasteners, and the plurality of third fasteners respectively fix the cover plate to the two first frames, wherein the plurality of third fasteners located on the first frame are arranged at intervals along the length direction of the first frame; The power conversion device comprises at least two fourth fasteners, wherein one of the fourth fasteners fixes the cover plate to one of the second frames, and another of the fourth fasteners fixes the cover plate to another of the second frames; The distance between the third fastener and the fourth fastener adjacent to the third fastener is greater than or equal to the distance between two adjacent third fasteners among the plurality of third fasteners located on the first frame, and the fastening force of the third fastener on the cover plate is greater than the fastening force of the fourth fastener on the cover plate.

4. The power conversion device according to claim 3, characterized in that: The plurality of third fasteners and the at least two fourth fasteners are all in contact with a side of the cover plate facing away from the shell, and a contact area between the third fasteners and the cover plate is greater than a contact area between the fourth fasteners and the cover plate.

5. The power conversion device according to claim 1, characterized in that: There are multiple explosion venting grooves, each of which is arranged on a diagonal line of the cover plate, and each of which extends along the diagonal line of the cover plate.

6. The power conversion device according to claim 1, characterized in that: There are multiple explosion relief grooves, and the multiple explosion relief grooves are arranged in a ring shape, and the multiple explosion relief grooves are evenly spaced from each other.

7. The power conversion device according to claim 1, characterized in that: There are multiple explosion relief grooves, and the multiple explosion relief grooves are arranged crosswise with each other.

8. The power conversion device according to claim 1, characterized in that: The depth of the explosion relief groove is less than or equal to half the thickness of the cover plate.

9. The power conversion device according to claim 1, characterized in that: The box body is provided with an explosion relief hole, and the box body includes an explosion relief piece, and the explosion relief piece covers the explosion relief hole and closes the receiving cavity.

10. The power conversion device according to claim 9, characterized in that: The explosion relief plate is provided with a first notch and a second notch, and the first notch and the second notch are arranged crosswise.

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