Power conversion device

Abstract

The embodiment of the application provides a kind of power conversion equipment, it is related to energy technical field.The power conversion equipment includes power conversion circuit, equipment shell, equipment cover and multiple fasteners;Equipment shell has the cavity for accommodating power conversion circuit, and the cavity mouth is communicated with the cavity;Equipment cover includes protection plate and connecting plate, protection plate covers cavity mouth, connecting plate is located at the side of protection plate towards cavity mouth, and the outer edge of connecting plate surrounds cavity mouth and is fixed to protection plate;Multiple fasteners are used to fix connecting plate and equipment shell;Wherein, connecting plate has explosion vent, in the circumferential direction of cavity mouth, explosion vent is at least partially located between two adjacent fasteners;Or, explosion vent is at least partially located on the side of one fastener away from the inner edge of connecting plate.By the above technical scheme, after the failure of power conversion equipment and explosion, the safety of power conversion equipment is improved on the basis of explosion vent, and the surrounding personnel are protected.

Description

Technical Field

[0001] This application relates to the field of energy technology, and in particular to a power conversion device. Background Technology

[0002] During operation, power conversion equipment (such as inverters and energy storage converters) may experience internal component failures under extreme conditions such as overvoltage and overtemperature, potentially generating flammable gases such as propane and methane. If these flammable gases ignite and explode inside the power conversion equipment, it will increase the internal pressure and potentially lift the equipment cover.

[0003] Because power conversion equipment has fasteners that secure the cover to the housing, the lifted cover, while not completely detached from the housing, creates a large gap between them, allowing for the release of gas pressure. This large gap allows personnel to access the circuit boards inside the power conversion equipment, potentially leading to electric shock, or causing debris or hot gases to be ejected from the housing and cause injury. Utility Model Content

[0004] This application provides a power conversion device that, in the event of a malfunction and explosion, improves the safety of the power conversion device by achieving explosion venting and protecting surrounding personnel.

[0005] To achieve the above objectives, this application adopts the following technical solution:

[0006] This application provides a power conversion device, which includes a power conversion circuit, a device housing, a device cover, and a plurality of fasteners. The power conversion circuit is used to convert direct current (DC) from photovoltaic modules or energy storage batteries into alternating current (AC). The device housing has a cavity for housing the power conversion circuit and an opening communicating with the cavity. The device cover includes a protective plate and a connecting plate. The protective plate covers the opening, and the connecting plate is located on the side of the protective plate facing the opening. The connecting plate is annular and at least a portion of its surface is perpendicular to the arrangement direction of the device housing and the device cover. The outer edge of the connecting plate surrounds the opening and is fixed to the protective plate. A plurality of fasteners are arranged circumferentially along the opening and are used to fix the connecting plate and the device housing. The connecting plate has an explosion vent, which is at least partially located between two adjacent fasteners in the circumferential direction of the opening; or, the explosion vent is at least partially located on the side of one of the fasteners away from the inner edge of the connecting plate.

[0007] The power conversion circuit in the power conversion equipment converts direct current (DC) from photovoltaic modules or energy storage batteries into alternating current (AC). The cavity inside the equipment housing houses the power conversion circuit, and a cover, fastened to the housing, shields the circuit within the cavity. In other words, the housing and cover together form the outer shell of the power conversion equipment. In the event of a malfunction, an internal explosion occurs, increasing the pressure within the space enclosed by the housing and cover. The explosion then forces the cover to be lifted out of the space.

[0008] Because fasteners secure the cover and housing, the cover, when lifted by an impact, will not completely detach from the housing. However, in the event of an explosion, the cover will deform. Since the fasteners secure the cover's connecting plate to the housing, the cover's protective plate will pull the connecting plate away from the housing under the impact, causing the connecting plate to deform. This deformed connecting plate will then be exposed and act as a shield. For example, without the connecting plate, a large gap would form between the protective plate and the housing after it is lifted. With the connecting plate, a portion of the connecting plate is pulled up by the protective plate, blocking this gap and reducing the likelihood of personnel coming into contact with the internal structure of the power conversion equipment, thus reducing the risk of electric shock. Furthermore, the connecting plate can shield against debris or high-temperature gases ejected from the power conversion equipment, improving its safety and protecting surrounding personnel.

[0009] Furthermore, after the connecting plate acts as a shield, the explosion vent on the connecting plate can release the gas in the cavity, achieving timely explosion venting and reducing the pressure in the cavity. In other words, after the power conversion equipment malfunctions and explodes, the connecting plate can not only provide shielding protection, but also release pressure through its explosion vent, thus achieving explosion venting.

[0010] In one optional embodiment, the power conversion device further includes a sealing ring, which surrounds the cavity opening and is sandwiched between the connecting plate and the device housing, with the explosion vent located inside the sealing ring.

[0011] The sealing ring seals the gap between the equipment housing and the cover. Furthermore, the explosion vent is located inside the sealing ring. When the power conversion equipment is functioning normally, the explosion vent is not connected to the outside, reducing the possibility of external impurities entering the power conversion equipment through the explosion vent. In the event of a malfunction and explosion, the cover is lifted and deformed, exposing the explosion vent inside the sealing ring and allowing it to release gas from the cavity, thus promptly venting the explosion.

[0012] In one optional embodiment, the vent includes multiple openings arranged circumferentially along the cavity opening.

[0013] Multiple openings of the explosion vent are arranged circumferentially around the cavity, so that the power conversion equipment is provided with openings for gas venting all around. The gas in the cavity can be vented to the outside of the power conversion equipment from multiple directions. In the event of a failure and explosion of the power conversion equipment, it is beneficial to achieve rapid explosion venting.

[0014] In one alternative embodiment, at least one opening is provided between every two adjacent fasteners in the circumferential direction of the cavity.

[0015] Under the impact of an explosion, the protective plate will pull the connecting plate away from the equipment casing. With the fasteners in place, the area on the connecting plate containing the fasteners will not deform significantly. However, the area between two adjacent fasteners will deform considerably under the pull of the protective plate. The area of ​​the connecting plate with the largest deformation (between two adjacent fasteners) will be exposed and act as a shield, reducing the possibility of a large gap forming between the equipment cover and the equipment casing. By placing the opening between two adjacent fasteners, after a power conversion device malfunctions and explodes, the area of ​​the connecting plate between the two adjacent fasteners deforms and is pulled up by the protective plate, allowing the opening to connect to the outside and achieve explosion venting.

[0016] In one alternative embodiment, each fastener or a portion of the fasteners has at least one opening on the side facing away from the inner edge of the connecting plate.

[0017] Under the pull of the protective plate (which, under the impact of an explosion, will pull the connecting plate away from the equipment casing), the area of ​​the fasteners away from the inner edge of the connecting plate will also deform and be pulled up by the protective plate, creating an opening in the area of ​​the fasteners away from the inner edge of the connecting plate. This opening allows for communication with the outside after a power conversion device malfunctions and explodes, thus achieving explosion venting. Alternatively, an opening can be provided in the area of ​​each fastener away from the inner edge of the connecting plate, or a suitable fastener can be selected with an opening in that area.

[0018] In one optional embodiment, the connecting plate includes four connecting segments arranged circumferentially along the cavity opening, wherein two connecting segments extend along a first direction and the other two connecting segments extend along a second direction, the first direction and the second direction are perpendicular to each other and both perpendicular to the arrangement direction of the equipment housing and the equipment cover, wherein two connecting segments are arranged along the second direction and the other two connecting segments are arranged along the first direction; each connecting segment is provided with at least one opening.

[0019] The near-square equipment cover is suitable for most power conversion devices. To accommodate more equipment housings, the connecting plate in the cover is also shaped like a square frame. Openings are provided on each connecting section of the connecting plate, with multiple openings arranged circumferentially along the cavity opening. This allows gas inside the cavity to be released from multiple directions to the outside of the power conversion device, facilitating explosion venting in the event of a power conversion device malfunction and explosion.

[0020] In one optional implementation, each connecting segment is provided with multiple openings, and the multiple openings on each connecting segment are arranged along the extension direction of the connecting segment.

[0021] Multiple openings are arranged along the extension direction of the connecting section, making full use of the length of the connecting section, making the arrangement of openings on each connecting section more reasonable, and also giving the connecting section more openings in its extension direction, which is conducive to releasing gas in the chamber.

[0022] In one alternative implementation, each opening on each connecting segment extends along the extension direction of the connecting segment.

[0023] The opening is elongated and extends along the extension direction of the connecting section, so that more areas of the connecting section in its extension direction are provided with openings that can vent explosions, which is beneficial for venting the gas in the chamber.

[0024] In one optional embodiment, the equipment cover further includes a surrounding plate located between the protective plate and the connecting plate. The surrounding plate is annular and surrounds the protective plate and the connecting plate. The outer edges of the protective plate and the connecting plate are fixedly connected to the surrounding plate, and there is a gap between the protective plate and the connecting plate.

[0025] By installing the enclosure, a gap can be created between the protective plate and the connecting plate. This gap is located in the edge area of ​​the equipment cover. In the event of a malfunction and explosion of the power conversion equipment, the internal gas of the equipment will fill this gap, increasing the pressure within it (increasing the pressure inside the space enclosed by the equipment casing and cover; this description focuses primarily on the gap). This pressure will push the edge of the protective plate away from the equipment casing, which facilitates the deformation of the connecting plate. Furthermore, in some cases, this gap also facilitates the installation and removal of fasteners.

[0026] In one alternative embodiment, a gap exists between the protective plate and the connecting plate, and each fastener passes through the device housing and the connecting plate and securely connects the device housing and the connecting plate, with a portion of each fastener extending into the gap.

[0027] Fasteners can be either screws or rivets. The fasteners pass through the connecting plate between the equipment housing and the equipment cover, which helps to secure the housing and cover together and reduces the possibility of them separating. A gap is formed between the protective plate and the connecting plate, which can accommodate part of the fastener, facilitating its installation. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of a photovoltaic energy storage system provided in an embodiment of this application;

[0029] Figure 2 This is a schematic diagram of the structure of a power conversion device provided in an embodiment of this application;

[0030] Figure 3 This application provides a topology diagram of a power conversion device according to an embodiment of the present application.

[0031] Figure 4 This is a schematic diagram of the structure of a device cover provided in an embodiment of this application;

[0032] Figure 5 A cross-sectional view of a device cover provided in an embodiment of this application;

[0033] Figure 6 A cross-sectional view of another device cover provided in an embodiment of this application;

[0034] Figure 7 A schematic diagram of the installation structure of a device housing and a device cover provided for an embodiment of this application;

[0035] Figure 8 A schematic diagram of another installation structure for a device housing and a device cover provided in an embodiment of this application;

[0036] Figure 9 This application provides a schematic diagram of the structure of a power conversion device under conditions of no fault and after a fault.

[0037] Figure 10 This is a schematic diagram of the structure of an explosion vent provided in an embodiment of this application;

[0038] Figure 11 This is a schematic diagram of another explosion vent structure provided in an embodiment of this application;

[0039] Figure 12 This is a schematic diagram of another explosion vent structure provided in an embodiment of this application;

[0040] Figure 13 This is a schematic diagram of another explosion vent structure provided in an embodiment of this application;

[0041] Figure 14This is a schematic diagram of the structure of another power conversion device after a failure, provided in an embodiment of this application.

[0042] Figure 15 This is a schematic diagram of the structure of a sealing ring provided in an embodiment of this application;

[0043] Figure 16 This is a diagram showing the positional relationship between a sealing ring and a vent, provided in an embodiment of this application.

[0044] Figure label:

[0045] 100-Photovoltaic-Storage System; 10-Photovoltaic Module; 20-Inverter; 30-Energy Storage Converter; 40-Grid; 50-Load; 60-Energy Storage Battery; 70-Power Conversion Equipment; 1-Power Conversion Circuit; 11-DC-DC Circuit; 12-DC-AC Circuit; 2-Equipment Housing; 21-Cavity; 22-Cavity Opening; 3-Equipment Cover; 31-Protective Plate; 32-Connecting Plate; 321-Explosion Vent; 3211-Opening; 322-Connecting Section; 33-Enclosure Plate; 34-Gap; 4-Fastener; 41-Stick; 42-Head; 401-First Fastener; 402-Second Fastener; 403-Third Fastener; 404-Fourth Fastener; 405-Fifth Fastener; 5-Sealing Ring. Detailed Implementation

[0046] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0047] In the accompanying drawings of the embodiments of this application, solid structures such as components and assemblies are represented by guide lines; structures composed of multiple components are represented by guide lines with parentheses or solid arrows; hollow structures such as cavities, openings, spaces, and bodies are represented by guide lines with hollow arrows.

[0048] In this application, the X-axis, Y-axis and Z-axis represent three mutually perpendicular coordinate axes in three-dimensional space.

[0049] Figure 1 An exemplary structure of a photovoltaic energy storage system 100 (solar photovoltaic energy storage power generation system) is shown, including a photovoltaic system and an energy storage system. (Refer to...) Figure 1In a photovoltaic system, photovoltaic modules 10 utilize the photovoltaic effect to directly convert solar energy into electrical energy. Photovoltaic modules 10 typically include multiple (two or more) solar cells connected in series or parallel to achieve a certain output power. Inverter 20 converts the direct current (DC) from photovoltaic modules 10 into alternating current (AC) and transmits the AC to the grid 40 or load 50. Alternatively, inverter 20 sends the AC to a corresponding prefabricated substation for voltage transformation. The prefabricated substation can convert the low-voltage AC output from inverter 20 into medium-voltage AC, which is then transmitted to a step-up substation and supplied to the grid 40 or load 50.

[0050] In energy storage systems, refer to Figure 1 The energy storage battery 60 converts direct current (DC) to alternating current (AC) via a power conversion system (PCS). After passing through a prefabricated substation corresponding to the energy storage battery 60, it delivers stable power to the grid 40 or the load 50. Alternatively, the power conversion system 30 can also convert AC power from the grid 40 to DC power to charge the energy storage battery 60, and then store the energy within the battery. Alternatively, in the energy storage system, the inverter 20 converts DC power to AC power to deliver stable power to the grid 40 or the load 50.

[0051] This application provides a power conversion device 70. Figure 2 An exemplary structure of a power conversion device 70 is shown, wherein the power conversion device 70 is used to convert one of alternating current and direct current into the other. In one embodiment, the power conversion device 70 is an inverter 20 (auxiliary reference). Figure 1 In one embodiment, the power conversion device 70 is used in a photovoltaic system to convert direct current (DC) from the photovoltaic module 10 into alternating current (AC) and output it to the grid 40 or the load 50. In another embodiment, the power conversion device 70 is an inverter 20 used in an energy storage system to convert DC from the energy storage battery 60 into AC. In some other embodiments, the power conversion device 70 is an energy storage converter 30 (see auxiliary reference). Figure 1 It is used in energy storage systems, where the power conversion device 70 is used to convert the DC power from the energy storage battery 60 into AC power.

[0052] Figure 3 An exemplary topology diagram of a power conversion device 70 is shown, with reference to... Figure 3The power conversion device 70 (two-stage mode power conversion device 70) includes a power conversion circuit 1, wherein the power conversion circuit 1 includes a DC-DC circuit 11 and a DC-AC circuit 12, and the input terminal of the DC-DC circuit 11 is used to connect to the photovoltaic module 10 or the energy storage battery 60 (auxiliary reference). Figure 1 The output terminal of DC-DC circuit 11 is electrically connected to the input terminal of DC-AC circuit 12. The output terminal of DC-AC circuit 12 is used to connect to the power grid 40 or the load 50 (auxiliary reference). Figure 1 Among them, the DC-DC circuit 11 is used to convert direct current (DC) power, for example, the DC-DC circuit 11 is used to boost or buck the voltage, and the DC-AC circuit 12 is used to convert direct current into alternating current (AC).

[0053] In some other examples, the power conversion device 70 (single-stage mode power conversion device 70) includes a DC-AC circuit 12 but not a DC-DC circuit 11. In this embodiment, the input of the DC-AC circuit 12 is used to connect to the photovoltaic module 10 or the energy storage battery 60, and the output of the DC-AC circuit 12 is used to connect to the power grid 40 or the load 50.

[0054] Understandably, the power conversion circuit 1 in the power conversion device 70 is used to convert direct current from the photovoltaic module 10 or the energy storage battery 60 into alternating current. Furthermore, the power conversion circuit 1 includes a circuit board and electronic components fixed on the circuit board.

[0055] The power conversion device 70 also includes a housing for accommodating the power conversion circuit 1, as shown in the reference. Figure 3 The aforementioned housing includes a housing 2 and a cover 3. The housing 2 has a cavity 21 for housing the power conversion circuit 1, and also has an opening 22 communicating with the cavity 21. It is understood that the structures within the cavity 21 need to be installed into the cavity 21 through the opening 22; for example, the circuit board and electronic components in the power conversion circuit 1 are installed into the cavity 21 through the opening 22. The cover 3 is positioned over the opening 22 and shields it to protect the power conversion circuit 1. After removing the cover 3, the power conversion circuit 1 inside the cavity 21 will be exposed to personnel.

[0056] Figure 4 An exemplary structure of a device cover 3 is shown. Figure 5 An exemplary cross-sectional view of a device cover 3 is shown, with reference to Figure 4 and Figure 5The equipment cover 3 includes a protective plate 31 and a connecting plate 32. The connecting plate 32 is annular (including a circular ring, square ring, or other irregular ring), and its outer edge (located at position A) is fixed to the protective plate 31. For example, the equipment cover 3 also includes a surrounding plate 33, through which the outer edge of the connecting plate 32 is fixed to the protective plate 31. That is, the surrounding plate 33 is located between the protective plate 31 and the connecting plate 32, and is annular, encircling the protective plate 31 and the connecting plate 32. The outer edges of the protective plate 31 (located at position B) and the connecting plate 32 (located at position A) are both fixedly connected to the surrounding plate 33. Furthermore, in some embodiments, referring to… Figure 4 and Figure 5 Any surface of the enclosure 33 is perpendicular to any surface of the connecting plate 32.

[0057] For example, Figure 6 An exemplary cross-sectional view of another device cover 3 is shown, with reference to Figure 6 The outer edge of the protective plate 31 (located at B) is fixedly connected to the outer edge of the connecting plate 32 (located at A), and... Figure 5 The illustrated embodiment differs in that, Figure 6 In the illustrated embodiment, there is no obvious structure as the enclosure 33; instead, the outer edge of the protective plate 31 is directly fixedly connected to the outer edge of the connecting plate 32.

[0058] The connecting plate 32 can be any suitable structure. For example, the connecting plate 32 includes multiple plate structures that are fixed to each other, forming an annular connecting plate 32. Alternatively, the connecting plate 32 includes multiple plate structures and at least one connector. The multiple plate structures are arranged circumferentially along the cavity 22. If there is a gap between two adjacent plate structures, a connector is provided between the two plate structures to fill the gap (if there is no gap between two adjacent plate structures, then no filling is required). The connector can also be used to fix two adjacent plate structures so that the multiple plate structures form an annular connecting plate 32. Another example is that the connecting plate 32 is an annular plate processed by integral molding.

[0059] The protective plate 31 and the connecting plate 32 can be fixed in any way. For example, the connecting plate 32 and the protective plate 31 can be integrally connected. The equipment cover 3 is formed by bending a metal plate to form the protective plate 31 and the connecting plate 32. Another example is that a part of the connecting plate 32 is integrally connected to the protective plate 31, and the rest of the connecting plate 32 is filled by the connector described in the previous paragraph. That is, a part of the connecting plate 32 (multiple plate structures in the upper section) and the protective plate 31 are first bent from a metal plate, and then the gap between two adjacent plate structures is filled by the connector (if there is no gap between two adjacent plate structures, then no filling is required), thereby forming the equipment cover 3. Yet another example is that the connecting plate 32 and the protective plate 31 are independent structures and are welded together.

[0060] After the device cover 3 is installed on the device housing 2, it can shield the power conversion circuit 1 inside the cavity. Figure 7 An exemplary mounting structure for a device housing 2 and a device cover 3 is shown, with reference to... Figure 7 The protective plate 31 covers the cavity 22. The connecting plate 32 is located on the side of the protective plate 31 facing the cavity 22. The outer edge of the connecting plate 32 (located at point A) surrounds the cavity 22, and at least a portion of the surface of the connecting plate 32 is perpendicular to the arrangement direction of the equipment housing 2 and the equipment cover 3 (parallel to the Z-axis). It should be noted that the surface of the connecting plate 32 refers to the surface of any side of the connecting plate 32, for example, the surface of the connecting plate 32 facing the protective plate 31, or, for example, the surface of the connecting plate 32 away from the protective plate 31. "At least a portion of the surface of the connecting plate 32" refers to a part or all of the surface of the connecting plate 32, for example, a part of the surface of the connecting plate 32 facing the protective plate 31, or, for example, all of the surface of the connecting plate 32 facing the protective plate 31, or, for example, a part of the surface of the connecting plate 32 away from the protective plate 31, or, for example, all of the surface of the connecting plate 32 away from the protective plate 31.

[0061] In order to fix the device cover 3 and the device housing 2, the power conversion device 70 also includes multiple (two or more) fasteners 4. The multiple fasteners 4 are arranged circumferentially along the cavity opening 22, and the multiple fasteners 4 are used to fix the connecting plate 32 and the device housing 2, thereby fixing the device cover 3 to the device housing 2 (or fixing the device housing 2 to the device cover 3).

[0062] exist Figure 7In the illustrated embodiment, the fastener 4 includes a rod 41 and a head 42. The head 42 is fixed to one end of the rod 41 and protrudes towards one side of the rod 41 radially (the Y direction is one of the radial directions of the rod 41). For example, the fastener 4 is a bolt or screw. The rod 41 passes through the device housing 2 and is threadedly connected to the device cover 3. The head 42 is located on the side of the device housing 2 opposite to the device cover 3 and abuts against the device housing 2. When installing the fastener 4, the rod 41 of the fastener 4 is inserted from one side of the device housing 2 and passes through the device housing 2. Rotating the fastener 4 achieves the threaded connection between the rod 41 and the device cover 3, and causes the head 42 of the fastener 4 to abut against the device housing 2, thereby fixing the device cover 3 to the device housing 2. When it is necessary to remove the fastener 4, the fastener 4 is rotated in the opposite direction from one side of the device housing 2, and then the fastener 4 is pulled out to remove it.

[0063] In some embodiments, refer to Figure 7 The equipment cover 3 includes a nut (the nut is part of the equipment cover 3), which is fixed (e.g., welded, glued, snapped, etc.) to the connecting plate 32, and a threaded hole that mates with the rod portion 41 is formed on the nut; in some other embodiments, the threaded hole may also be machined on the connecting plate 32 of the equipment cover 3.

[0064] Fastener 4 can also secure the device cover 3 to the device housing 2 in other suitable ways, for example, Figure 8 An exemplary mounting structure for the device housing 2 and the device cover 3 is shown, with reference to... Figure 8 The rod 41 passes through the connecting plate 32 and is threadedly connected to the equipment housing 2, with the head 42 located between the connecting plate 32 and the protective plate 31. In this embodiment, when installing the fastener 4, the rod 41 of the fastener 4 is inserted from one side of the equipment cover 3 and passes through the connecting plate 32, so that the rod 41 is threadedly connected to the equipment housing 2, and the head 42 of the fastener 4 abuts against the connecting plate 32, thereby fixing the equipment cover 3 to the equipment housing 2. When it is necessary to remove the fastener 4, the fastener 4 is rotated in the opposite direction from one side of the equipment cover 3, and then the fastener 4 is pulled out.

[0065] In some embodiments, refer to Figure 8 The device housing 2 includes a nut, which is fixed (e.g., welded, glued, snapped, etc.) to the device housing 2, and a threaded hole that mates with the rod 41 is formed on the nut; in some other embodiments, a threaded hole may also be machined on the device housing 2 to mate with the rod 41.

[0066] exist Figure 7 and Figure 8In the illustrated embodiment, each fastener 4 passes through the device housing 2 and the connecting plate 32, and each fastener 4 securely connects the device housing 2 and the connecting plate 32. Therefore, a gap 34 is required between the protective plate 31 and the connecting plate 32 so that a portion of each fastener 4 can extend into the gap 34. This gap 34 can be formed between the protective plate 31 and the connecting plate 32 by providing a surrounding plate 33 (e.g., Figure 5 The device cover 3 shown can also be the gap 34 formed between the protective plate 31 and the connecting plate 32 after bending (e.g., the gap 34 between the protective plate 31 and the connecting plate 32). Figure 6 The device cover 3 is shown. The gap 34 between the protective plate 31 and the connecting plate 32 can accommodate a part of the fastener 4, which facilitates the installation of the fastener 4.

[0067] In some other embodiments, the fastener 4 is a rivet that passes through the connecting plate 32 of the device housing 2 and the device cover 3, thereby fixing the device housing 2 and the device cover 3 together and reducing the possibility of the device housing 2 and the device cover 3 separating from each other.

[0068] In addition, after the power conversion device 70 is installed in a designated location (column, wall, etc.), the protective plate 31 of the device cover 3 can be directly seen by personnel. The protective plate 31 covers the fasteners 4, making the power conversion device 70 more aesthetically pleasing.

[0069] Figure 9 Exemplary diagrams illustrate a power conversion device 70 in a fault-free state and a power conversion device 70 in a fault-free state. When the power conversion device 70 is operating normally (no fault occurs), refer to... Figure 9 In (a), the equipment cover 3 is normally installed on the equipment housing 2 by fasteners 4 (shown by dashed boxes), wherein the connecting plate 32 of the equipment cover 3 is obscured and not directly visible. After a malfunction of the power conversion device 70, refer to... Figure 9 In scenario (b), an internal combustion explosion occurs within the power conversion device 70. The internal pressure within the space enclosed by the device housing 2 and the device cover 3 increases. The device cover 3 is subjected to the impact force generated by the explosion, which strikes the device cover 3 in a direction away from the device housing 2. The device cover 3 is lifted up by the impact. Because the fasteners 4 secure the device cover 3 and the device housing 2, the lifted device cover 3 will not completely detach from the device housing 2. However, under the impact of the explosion, the device cover 3 will deform. Furthermore, since the fasteners 4 secure the connecting plate 32 between the device housing 2 and the device cover 3, the protective plate 31 will pull the connecting plate 32 in a direction away from the device housing 2 under the impact of the explosion, thus deforming the connecting plate 32.

[0070] Reference Figure 9In (b), the deformed connecting plate 32 is exposed and acts as a shield. For example, without the connecting plate 32, a large gap would be formed between the protective plate 31 and the equipment housing 2 after the protective plate 31 is lifted. However, with the connecting plate 32 installed, a part of the connecting plate 32 is pulled up by the protective plate 31, which shields the gap and reduces the possibility of personnel coming into contact with the internal structure of the power conversion equipment 70, thus reducing the risk of electric shock. In addition, the connecting plate 32 can shield fragments or high-temperature gases that fly out of the power conversion equipment 70, improving the safety of the power conversion equipment 70 and protecting the surrounding personnel.

[0071] In addition, a gap 34 is formed between the protective plate 31 and the connecting plate 32 (for auxiliary reference). Figure 8 In the case of a power conversion device 70 failure and explosion, the gap 34 is located in the edge area of ​​the device cover 3. After the power conversion device 70 fails and explodes, the internal gas of the power conversion device 70 will fill the gap 34, increasing the pressure inside the gap 34 (increasing the pressure inside the space enclosed by the device shell 2 and the device cover 3; the description here mainly focuses on the gap 34), and pushing the edge of the protective plate 31 toward the side away from the device shell 2. After the edge of the protective plate 31 is pushed up, it is beneficial to pull the connecting plate 32 to deform.

[0072] In addition, refer to Figure 9 In (b), the connecting plate 32 has an explosion vent 321 (for easy distinction, Figure 9 (Shaded out in explosion vent 321) After the connecting plate 32 provides shielding and protection, the explosion vent 321 on the connecting plate 32 can release the gas in the cavity 21, achieving timely explosion venting and reducing the pressure in the cavity 21. In other words, by using the connecting plate 32 for shielding and the explosion vent 321 on the connecting plate 32 for pressure relief, the safety of the power conversion equipment 70 is improved and surrounding personnel are protected after a malfunction and explosion of the power conversion equipment 70.

[0073] In some embodiments, at least a portion (or all) of the vent 321 is located between two adjacent fasteners 4 in the circumferential direction of the cavity 22. For example, Figure 10 An exemplary structure of a vent 321 is shown (for ease of distinction, Figure 10 (Put a shaded line in explosion vent 321), see reference. Figure 10 The explosion vent 321 includes multiple openings 3211, and multiple fasteners 4 include a first fastener 401 and a second fastener 402 arranged adjacent to each other. One of the openings 3211 is located between the first fastener 401 and the second fastener 402, so that a part of the explosion vent 321 is located between two adjacent fasteners 4.

[0074] For example, Figure 11 An exemplary diagram shows another structure of the explosion vent 321 (for easy distinction, Figure 11 (Put a shaded line in explosion vent 321), see reference. Figure 11 The explosion vent 321 includes multiple openings 3211, and multiple fasteners 4 include a first fastener 401 and a second fastener 402 arranged adjacent to each other. At least two openings 3211 (not all openings 3211) are located between the first fastener 401 and the second fastener 402, thus also being part of the explosion vent 321 located between two adjacent fasteners 4.

[0075] For example, the explosion vent 321 is an independent structure (e.g., the explosion vent 321 includes an opening 3211), and the multiple fasteners 4 include adjacent first fasteners 401 and second fasteners 402. The explosion vent 321 is entirely located between the first fasteners 401 and second fasteners 402, thus the entire explosion vent 321 is located between two adjacent fasteners 4. Alternatively, the explosion vent 321 includes multiple openings 3211, and the multiple fasteners 4 include adjacent first fasteners 401 and second fasteners 402. All openings 3211 are located between the first fasteners 401 and second fasteners 402, thus the entire explosion vent 321 is located between two adjacent fasteners 4.

[0076] Among them, the return reference Figure 9 Under the impact of an explosion, the protective plate 31 will pull the connecting plate 32 away from the equipment housing 2. With the fasteners 4 in place, the area where the fasteners 4 are located on the connecting plate 32 will not deform significantly. However, the area between two adjacent fasteners 4 will deform significantly under the pull of the protective plate 31. The area of ​​the connecting plate 32 with the larger deformation (the area between two adjacent fasteners 4) will be exposed and act as a shield, reducing the possibility of a large gap forming between the equipment cover 3 and the equipment housing 2. By placing at least a portion of the explosion vent 321 between two adjacent fasteners 4, after the power conversion equipment 70 malfunctions and explodes, the area of ​​the connecting plate 32 between the two adjacent fasteners 4 will deform, allowing the explosion vent 321 to connect with the outside world and achieve explosion venting.

[0077] In other embodiments, at least a portion of the vent 321 is located on the side of one of the fasteners 4 facing away from the inner edge of the connecting plate 32. For example, Figure 12 An exemplary embodiment shows the structure of another explosion vent 321 (for easy distinction, Figure 12 (Put a shaded line in explosion vent 321), see reference. Figure 12The explosion vent 321 includes multiple openings 3211, and multiple fasteners 4 include a first fastener 401. One of the openings 3211 is located on the side of the first fastener 401 away from the inner edge of the connecting plate 32 (the position indicated by C). Thus, a portion of the explosion vent 321 is located on the side of one of the fasteners 4 away from the inner edge of the connecting plate 32.

[0078] For example, Figure 13 An exemplary embodiment shows the structure of another explosion vent 321 (for easy distinction, Figure 13 (Put a shaded line in explosion vent 321), see reference. Figure 13 The explosion vent 321 includes multiple openings 3211, and multiple fasteners 4 include a first fastener 401. At least two openings 3211 (not all openings 3211) are located on the side of the first fastener 401 away from the inner edge of the connecting plate 32 (the position indicated by C). Thus, part of the explosion vent 321 is located on the side of one of the fasteners 4 away from the inner edge of the connecting plate 32.

[0079] For example, the explosion vent 321 is an independent structure (e.g., the explosion vent 321 includes an opening 3211), and multiple fasteners 4 include a first fastener 401. The explosion vent 321 is entirely located on the side of the first fastener 401 away from the inner edge of the connecting plate 32. Thus, the entire explosion vent 321 is located on the side of one of the fasteners 4 away from the inner edge of the connecting plate 32. Alternatively, the explosion vent 321 includes multiple openings 3211, and multiple fasteners 4 include a first fastener 401. All openings 3211 are located on the side of the first fastener 401 away from the inner edge of the connecting plate 32. Again, the entire explosion vent 321 is located on the side of one of the fasteners 4 away from the inner edge of the connecting plate 32.

[0080] in, Figure 14 An exemplary diagram illustrates the structure of another power conversion device 70 after a failure (for ease of distinction, Figure 14 (Put a shaded line in explosion vent 321), see reference. Figure 14 After the power conversion device 70 malfunctions and explodes, the protective plate 31 will pull the connecting plate 32 away from the device housing 2 under the impact of the explosion. The area of ​​the fastener 4 away from the inner edge of the connecting plate 32 will also deform and be pulled up by the protective plate 31. At least a portion of the explosion vent 321 is located in the area of ​​the fastener 4 away from the inner edge of the connecting plate 32. After the power conversion device 70 malfunctions and explodes, the explosion vent 321 can be exposed and connected to the outside, thus achieving explosion venting.

[0081] In order to enable the explosion vent 321 to better vent explosions, in some embodiments, a reference is returned. Figures 10 to 13In any one of them, the explosion vent 321 includes a plurality of openings 3211, which are arranged circumferentially along the cavity opening 22, wherein, Figures 10 to 13 The dashed box in the diagram exemplarily indicates the location of the cavity 22. The size of the cavity 22 can be larger or smaller than the size of the dashed box, and this application does not impose specific limitations on this. Multiple openings 3211 of the explosion vent 321 are arranged circumferentially around the cavity 22, so that the power conversion device 70 is provided with explosion venting openings 3211 around its perimeter. This allows the gas inside the cavity 21 to be released from multiple directions to the outside of the power conversion device 70, which is beneficial for explosion venting after a malfunction and explosion of the power conversion device 70.

[0082] In the case where the explosion vent 321 includes multiple openings 3211, refer to Figure 10 In the circumferential direction of the cavity opening 22, an opening 3211 is provided between every two adjacent fasteners 4, so that multiple openings 3211 are arranged along the circumferential direction of the cavity opening 22. (Refer to...) Figure 11 In the circumferential direction of the cavity opening 22, multiple openings 3211 are provided between every two adjacent fasteners 4, and the multiple openings 3211 can also be arranged along the circumferential direction of the cavity opening 22. (Refer to...) Figure 12 A portion of the fasteners 4 have an opening 3211 on the side facing away from the inner edge of the connecting plate 32. For example, the fasteners 4 include a first fastener 401, a third fastener 403, a fourth fastener 404, and a fifth fastener 405. In each of these fasteners, an opening 3211 is provided on the side facing away from the inner edge of the connecting plate 32. (Refer to...) Figure 13 A number of fasteners 4 have multiple openings 3211 on the side facing away from the inner edge of the connecting plate 32. For example, in the first fastener 401, the third fastener 403, the fourth fastener 404, and the fifth fastener 405, each fastener 4 has multiple openings 3211 on the side facing away from the inner edge of the connecting plate 32. Figure 13 (The case with four openings 3211 is shown). Furthermore, in some embodiments, in all fasteners 4, each fastener 4 has one or more openings 3211 on the side facing away from the inner edge of the connecting plate 32.

[0083] The location of the explosion vent 321 can also be designed and adjusted according to the structure of the equipment cover 3, for example, referring to... Figures 10 to 13Any one of these options makes the device cover 3 approximately square. An approximately square device cover 3 can be adapted to most power conversion devices 70. To facilitate adaptation to more device housings 2, the shape of the connecting plate 32 in the device cover 3 is also similar to a square frame. The connecting plate 32 of the device cover 3 includes four connecting segments 322 arranged circumferentially along the cavity opening 22. Two connecting segments 322 extend along a first direction (parallel to the X-axis), and the other two connecting segments 322 extend along a second direction (parallel to the Y-axis). The first and second directions are perpendicular to each other, and both the first and second directions are perpendicular to the arrangement direction of the device housing 2 and the device cover 3 (parallel to the Z-axis). Furthermore, two connecting segments 322 extending along the first direction are arranged along the second direction, and two connecting segments 322 extending along the second direction are arranged along the second direction. In the case where the explosion vent 321 includes multiple openings 3211, each connecting segment 322 is provided with at least one opening 3211.

[0084] In this design, an opening 3211 is provided on each connecting section 322 of the connecting plate 32, so that multiple openings 3211 are arranged circumferentially along the cavity 22. The gas in the cavity 21 can be released from multiple directions to the outside of the power conversion device 70. This is beneficial for venting the explosion after the power conversion device 70 fails and explodes.

[0085] For example, refer to Figure 10 Each opening 3211 on each connecting segment 322 extends along the extension direction of the connecting segment 322. That is, the opening 3211 on the connecting segment 322 extending along the first direction also extends along the first direction, and the opening 3211 on the connecting segment 322 extending along the second direction also extends along the second direction. This makes the opening 3211 elongated, and the connecting segment 322 is provided with more explosion-venting openings 3211 in more areas along its extension direction, which is beneficial for venting gas in the chamber.

[0086] For example, refer to Figure 11 Each connecting segment 322 is provided with multiple openings 3211. These openings 3211 on each connecting segment 322 are arranged along the extension direction of that segment. Specifically, all openings 3211 on connecting segments extending in a first direction are arranged along the first direction, and all openings 3211 on connecting segments extending in a second direction are arranged along the second direction. This arrangement of multiple openings 3211 along the extension direction of the connecting segment 322 makes full use of the length of the connecting segment 322, resulting in a more rational arrangement of the openings 3211 on each connecting segment 322. It also provides more openings 3211 in the extension direction of the connecting segment 322, which is beneficial for venting gas from the chamber.

[0087] For example, refer to Figure 12The opening 3211 is a long, narrow slit. Each opening 3211 on each connecting segment 322 extends along the extension direction of the connecting segment 322, allowing more areas of the connecting segment 322 to have openings 3211 in its extension direction, which is beneficial for releasing gas from the chamber. For example, refer to... Figure 13 Each connecting segment 322 is provided with multiple openings 3211. The multiple openings 3211 on each connecting segment 322 are arranged along the extension direction of the connecting segment 322, which also makes full use of the length of the connecting segment 322 and makes the arrangement of the openings 3211 on each connecting segment 322 more reasonable.

[0088] The shape of each opening 3211 can be set according to requirements, for example, referring to Figure 10 The opening 3211 is a long, rectangular opening; for example, refer to Figure 11 Opening 3211 is a hole with a square cross-section; for example, refer to Figure 12 The opening 3211 is a long, narrow slit. Figure 12 The size of the opening 3211 in the first direction (parallel to the X-axis) is smaller than Figure 10 The size of the opening 3211 in the first direction, Figure 12 The size of the opening 3211 in the second direction (parallel to the Y-axis) is greater than Figure 10 The opening 3211 in the middle is the dimension in the second direction; for example, refer to Figure 13 The opening 3211 is a hole with a circular cross-section. In some other embodiments, the shape of the opening 3211 may also be irregular.

[0089] Furthermore, in some embodiments, the power conversion device 70 also includes a sealing ring 5. Figure 15 An exemplary structure of a sealing ring 5 is shown, with reference to Figure 15 The sealing ring 5 surrounds the cavity opening 22 and is sandwiched between the connecting plate 32 and the equipment housing 2. The sealing ring 5 seals the gap between the equipment housing 2 and the equipment cover 3, reducing the possibility of external impurities entering the power conversion equipment 70 and affecting its normal operation. Figure 16 An exemplary illustration shows the positional relationship between the explosion vent 321 and the sealing ring 5 (for easy distinction, Figure 16 (Put a shaded line in explosion vent 321), see reference. Figure 16 The explosion vent 321 is located inside the sealing ring 5, that is, the sealing ring 5 surrounds the explosion vent 321. When the explosion vent 321 includes multiple openings 3211, all openings 3211 are located inside the sealing ring 5.

[0090] By setting the sealing ring 5, the explosion vent 321 will not be connected to the outside when the power conversion device 70 is not malfunctioning, reducing the possibility of external impurities entering the power conversion device 70. After the power conversion device 70 malfunctions and explodes, the device cover 3 is lifted and deformed, exposing the explosion vent 321 inside the sealing ring 5 and connecting it to the outside. The explosion vent 321 releases the gas in the cavity 21, achieving timely explosion venting.

[0091] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A power conversion device, characterized in that, include: A power conversion circuit for converting direct current (DC) from photovoltaic modules or energy storage batteries into alternating current (AC). The device housing has a cavity for housing the power conversion circuit and an opening communicating with the cavity; The equipment cover includes a protective plate and a connecting plate. The protective plate covers the cavity opening. The connecting plate is located on the side of the protective plate facing the cavity opening. The connecting plate is annular and at least a portion of its surface is perpendicular to the arrangement direction of the equipment shell and the equipment cover. The outer edge of the connecting plate surrounds the cavity opening and is fixed to the protective plate. Multiple fasteners are arranged circumferentially along the cavity opening, and the multiple fasteners are used to fix the connecting plate and the device housing; The connecting plate has an explosion vent, which is located at least partially between two adjacent fasteners in the circumferential direction of the cavity; or, the explosion vent is located at least partially on the side of one of the fasteners away from the inner edge of the connecting plate.

2. The power conversion device according to claim 1, characterized in that, The power conversion device also includes a sealing ring, which surrounds the cavity opening and is sandwiched between the connecting plate and the device housing. The explosion vent is located inside the sealing ring.

3. The power conversion device according to claim 1 or 2, characterized in that, The explosion vent includes multiple openings arranged circumferentially along the cavity opening.

4. The power conversion device according to claim 3, characterized in that, In the circumferential direction of the cavity, at least one opening is provided between every two adjacent fasteners.

5. The power conversion device according to claim 3, characterized in that, Each of the fasteners or a portion of the fasteners has at least one opening on the side facing away from the inner edge of the connecting plate.

6. The power conversion device according to any one of claims 3-5, characterized in that, The connecting plate includes four connecting segments arranged circumferentially along the cavity opening, wherein two of the connecting segments extend along a first direction and the other two of the connecting segments extend along a second direction. The first direction and the second direction are perpendicular to each other and both are perpendicular to the arrangement direction of the device housing and the device cover. Two of the connecting segments are arranged along the second direction and the other two of the connecting segments are arranged along the first direction. Each of the connecting segments is provided with at least one of the openings.

7. The power conversion device according to claim 6, characterized in that, Each of the connecting segments is provided with a plurality of openings, and the plurality of openings on each connecting segment are arranged along the extension direction of the connecting segment.

8. The power conversion device according to claim 6, characterized in that, Each opening on each of the connecting segments extends along the extension direction of the connecting segment in which it is located.

9. The power conversion device according to any one of claims 1-8, characterized in that, The equipment cover also includes a surrounding plate, which is located between the protective plate and the connecting plate. The surrounding plate is annular and surrounds the protective plate and the connecting plate. The outer edges of the protective plate and the connecting plate are fixedly connected to the surrounding plate, and there is a gap between the protective plate and the connecting plate.

10. The power conversion device according to any one of claims 1-9, characterized in that, There is a gap between the protective plate and the connecting plate. Each of the fasteners passes through the device housing and the connecting plate and is fixedly connected to the device housing and the connecting plate. A portion of each fastener extends into the gap.

Images