Photovoltaic inverter

Abstract

The photovoltaic inverter comprises a shell with an inner cavity and a first circuit board located in the inner cavity, components are arranged on the front face of the first circuit board, and a heat dissipation base used for dissipating heat of the components is arranged on the back face of the first circuit board. The photovoltaic inverter comprises an inner cavity, a first circuit board and a plurality of components, the components correspond to and are connected with the heat dissipation base, the photovoltaic inverter further comprises a plurality of first wind shielding pieces, the inner cavity is divided into a first heat dissipation channel by the first wind shielding pieces and the back face of the first circuit board, and the heat dissipation base is exposed in the first heat dissipation channel; the photovoltaic inverter further comprises a fan module arranged in the inner cavity, the fan module comprises a fan and is provided with an air inlet or an air outlet, and one of the air inlet and the air outlet is communicated with the first heat dissipation channel. The photovoltaic inverter provided by the invention can effectively prevent the internal circuit board from generating heat accumulation, thereby improving the use reliability of the photovoltaic inverter.

Description

Technical Field

[0001] The invention belongs to the field of electric power equipment, and in particular relates to a photovoltaic inverter. Background Art

[0002] A photovoltaic inverter (PV inverter or solar inverter) is an inverter that can convert the variable DC voltage generated by photovoltaic (PV) solar panels into AC power at mains frequency, which can be fed back to the commercial transmission system or used for off-grid power grids.

[0003] As the power of photovoltaic inverters increases, the heat generated by the power devices on the circuit boards inside the photovoltaic inverter chassis also increases. Soldering heat sinks on the circuit boards is a common heat dissipation method. Due to layout, space and other reasons, the heat sink is often set on the back of the circuit board (the side opposite to the components). Since the distance from the circuit board to the bottom or top of the box is small, the heat on the heat sink cannot be taken away in time through the internal air circulation, which easily causes local heat accumulation, thereby affecting the service life of the photovoltaic inverter. In the past, thermal conductive silicone sheets were usually used to transfer heat to the box or radiator. However, due to the scattered distribution of power devices and heat sinks, the use of silicone sheets is subject to many restrictions. Therefore, how to effectively solve the problem of heat accumulation on the circuit board has become a technical problem that needs to be solved urgently. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a photovoltaic inverter, which can effectively prevent heat accumulation on the internal circuit board, thereby improving the reliability of the photovoltaic inverter.

[0005] In order to achieve the above object, the present invention adopts the following technical scheme:

[0006] A photovoltaic inverter comprises a shell having an inner cavity and a first circuit board located in the inner cavity, components are arranged on the front side of the first circuit board, a heat sink for dissipating heat of the components is arranged on the back side of the first circuit board, the components and the heat sink correspond to and are connected to each other, the photovoltaic inverter also comprises a plurality of first wind shields, the inner cavity is separated into a first heat dissipation channel by the first wind shields and the back side of the first circuit board, and the heat sink is exposed in the first heat dissipation channel; the photovoltaic inverter also comprises a fan module arranged in the inner cavity, the fan module comprises a fan and has an air inlet or an air outlet, and one of the air inlet and the air outlet is connected to the first heat dissipation channel.

[0007] In a preferred embodiment, the fan module further includes a base, the fan is located on the base, the air inlet side of the fan faces the inner cavity of the base, and the air outlet side of the fan faces the first heat dissipation channel.

[0008] In a preferred embodiment, the air inlet is provided on the base, and the air inlet includes a first air inlet and a second air inlet, and the first heat dissipation channel is connected to the air inlet side of the fan through the first air inlet.

[0009] In a preferred embodiment, the heat sink is a heat dissipation copper bar, and the heat dissipation copper bar is welded on the back side of the circuit board.

[0010] In a preferred embodiment, the first wind shield is bonded to the bottom plate of the housing or the first circuit board; the first wind shield is made of insulating soft material.

[0011] In a preferred embodiment, the photovoltaic inverter further includes a second circuit board, a support plate for supporting the second circuit board, and a plurality of second wind shields, components are provided on the front of the second circuit board, a heat sink for dissipating heat from the components is provided on the back of the second circuit board, the components and the heat sink correspond to and are connected to each other, the inner cavity is divided into a second heat dissipation channel by the second wind shield, the support plate, and the back of the second circuit board, the heat sink is exposed in the second heat dissipation channel, and the second heat dissipation channel is connected to the second air inlet. The position of the second wind shield can be flexibly adjusted according to the layout of the heat sink.

[0012] In a more preferred embodiment, the second heat dissipation channel is connected to the air inlet side of the fan through the second air inlet.

[0013] In a more preferred embodiment, the second air inlet is located above the first air inlet and the first air inlet is communicated with the second air inlet, and the air outlet side of the fan is located between the first air inlet and the second air inlet.

[0014] In a preferred embodiment, the second wind shield is bonded to the support plate or the second circuit board; the second wind shield is made of insulating soft material.

[0015] In a preferred embodiment, a first sealing strip is provided between the first air inlet and the first wind shield, and a second sealing strip is provided between the second air inlet and the second wind shield. The first sealing strip and the second sealing strip are conducive to absorbing more cold air.

[0016] The present invention adopts the above solution, which has the following advantages compared with the prior art:

[0017] The photovoltaic inverter of the present invention starts the fan module, and the air inlet of the fan module draws the gas with a relatively low temperature inside the photovoltaic inverter. The gas with a relatively low temperature dissipates the heat to the heat sink on the circuit board through the first heat dissipation channel. The temperature inside the photovoltaic inverter is evenly adjusted, and the phenomenon of local heat accumulation on the circuit board is avoided, thereby improving the reliability of the use of the photovoltaic inverter. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solution of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0019] Figure 1 is a three-dimensional diagram of a photovoltaic inverter according to an embodiment of the present invention;

[0020] Figure 2 is an internal schematic diagram of a photovoltaic inverter according to an embodiment of the present invention;

[0021] Figure 3 is a schematic diagram of a fan module according to an embodiment of the present invention;

[0022] Figure 4 is a schematic diagram of a first heat dissipation channel;

[0023] Figure 5 is a right side view of a photovoltaic inverter according to an embodiment of the present invention;

[0024] Figure 6 is a front view of a photovoltaic inverter according to an embodiment of the present invention;

[0025] Figure 7 A schematic diagram of the base.

[0026] in,

[0027] 100, photovoltaic inverter; 101, housing; 1011, bottom plate; 102, first circuit board; 103, second circuit board;

[0028] 200, heat dissipation copper bar;

[0029] 1. fan module; 11. base; 111. hollow portion; 112. side wall; 113. top wall; 12. fan; 121. air outlet side; 13. first air inlet; 14. second air inlet;

[0030] 2. Support plate; 3. First heat dissipation channel; 31. First wind shield; 4. Second heat dissipation channel; 41. Second wind shield; 5. First sealing strip; 51. Second sealing strip; 6. Support column. DETAILED DESCRIPTION

[0031] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0032] Reference Figures 1 to 7 As shown, this embodiment provides a photovoltaic inverter 100, including a shell 101, a first circuit board 102 located in the inner cavity of the shell 101, and a second circuit board 103. Here, the number of circuit boards is not limited, and can be set to one or more according to actual usage. Specifically in this embodiment, the number of circuit boards in the shell 101 is two, and the first circuit board 102 and the second circuit board 103 are placed up and down.

[0033] Further, the photovoltaic inverter 100 also includes a fan module 1, a first heat dissipation channel 3, and a second heat dissipation channel 4 located in the inner cavity of the housing 101. The fan module 1 is fixed to the housing 101 by a plurality of fasteners, and the fan module 1 includes a base 11 and a fan 12 located on the base 11, and the fan 12 is fixed to the base 11 by a plurality of screws. More specifically, a hollow portion 111 is provided on the base 11, and the fan 12 is fixed to the hollow portion 111 by a plurality of screws. The hollow portion 111 can be arranged on the side wall 112 of the base 11, or on the top wall 113 of the base 11. Specifically in this embodiment, the hollow portion 111 is arranged on the side wall 112 of the base 11, and in other embodiments, the hollow portion 111 can also be arranged on other side walls or the top wall 113 of the base 11. The base 11 is made of insulating material or is wrapped with insulating material outside the base 11. The base 11 also has an inner cavity. The fan 12 has an air inlet side and an air outlet side 121. Further, the air inlet side of the fan 12 faces the inner cavity of the base 11 and the air inlet side of the fan is connected to the inner cavity. The air outlet side 121 of the fan 12 faces the first heat dissipation channel 3. Furthermore, the distance between the air inlet side of the fan 12 and the rear wall of the base 11 is greater than half the diameter of the circle surrounded by the blades of the fan 12, ensuring that the wind resistance of the air inlet is small and there is a large air inlet space. At this time, the rear wall refers to a side arranged opposite to the side wall where the fan is installed.

[0034] Components are arranged on the front of the first circuit board 102, and a heat sink for dissipating the heat of the components is arranged on the back of the first circuit board 102, and the components and the heat sink correspond to each other and are connected to each other. Components are arranged on the front of the second circuit board 103, and a heat sink for dissipating the heat of the components is arranged on the back of the second circuit board 103, and the components and the heat sink correspond to each other and are connected to each other. The photovoltaic inverter also includes a plurality of first windshields 31, a support plate 2 for supporting the second circuit board 103, and a plurality of second windshields 41. The inner cavity of the photovoltaic inverter is divided into a first heat dissipation channel 3 by the first windshield 31 and the back of the first circuit board 102, and the heat sink is exposed in the first heat dissipation channel 3; the inner cavity of the photovoltaic inverter is divided into a second heat dissipation channel 4 by the second windshield 41, the support plate 2 and the back of the second circuit board 103, and the heat sink is exposed in the second heat dissipation channel 4, wherein the support plate 2 is connected to the housing 101 through a plurality of support columns 6.

[0035] Further, the fan module 1 has an air inlet and an air outlet, and the air outlet is the above-mentioned air outlet side 121. Specifically, the air inlet is arranged on the base 11 and the base 11 is provided with a first air inlet 13 and a second air inlet 14. The first air inlet 13 is connected to the first heat dissipation channel 3, and the second air inlet 14 is connected to the second heat dissipation channel 4. More specifically, the first heat dissipation channel 3 is connected to the air inlet side of the fan 12 through the first air inlet 13, and the second heat dissipation channel 4 is connected to the air inlet side of the fan 12 through the second air inlet 14. The second air inlet 14 is located above the first air inlet 13 and the first air inlet 13 and the second air inlet 14 are connected. The air outlet side 121 of the fan 12 is located between the first air inlet 13 and the second air inlet 14. The fan 12 can extract heat from the first heat dissipation channel 3 and the second heat dissipation channel 4 at the same time. The cross-sectional areas of the first air inlet 13 and the second air inlet 14 are greater than or equal to the cross-sectional area of ​​the air outlet side of the fan 12 , so that the fan 12 can draw more cold air and reduce the air outlet resistance.

[0036] Specifically, the heat sinks on the first circuit board 102 and the second circuit board 103 are heat sink copper bars 200, and the number of heat sink copper bars 200 is multiple, refer to Figure 2 As shown, the shape or arrangement of the first wind shield 31 and the second wind shield 41 is mainly based on the distribution of the heat dissipation copper bar, and the heat dissipation effect can also be increased by increasing the opening area of ​​the first wind shield 31 and the second wind shield 41.

[0037] The first windshield member 31 and the second windshield member 41 of this embodiment are made of insulating soft material and only one side is provided with adhesive. The thickness of the first windshield member 31 and the second windshield member 41 is 10-15 mm. Figure 2As shown, the first windshield 31 is compressed between the first circuit board 102 and the housing 101. Specifically, the housing 101 has a bottom plate 1011, the first heat dissipation channel 3 is located between the first circuit board 101, the bottom plate 1011 and the first windshield 31, the heat dissipation copper bar 200 of the first circuit board 102 is located in the first heat dissipation channel 3, and the first windshield 31 is bonded to the bottom plate 1011 of the housing 101 or the first circuit board 102. The second windshield 41 is compressed between the second circuit board 103 and the support plate 2, and the second windshield 41 is bonded to the support plate 2 or the second circuit board 103. It should be noted that, in order to facilitate disassembly, the first windshield 31 will not be bonded to the bottom plate 1011 and the first circuit board 102 at the same time, and the second windshield 41 will not be bonded to the support plate 2 and the second circuit board 103 at the same time.

[0038] Furthermore, a first sealing strip 5 is provided between the first air inlet 13 and the first wind shield 31, and a second sealing strip 51 is provided between the second air inlet 14 and the second wind shield 41. The first sealing strip 5 and the second sealing strip 51 can ensure sufficient air intake. The number of the first wind shield 31 and the second wind shield 41 are both two. When the heat sink on the circuit board needs to be cooled, the fan 12 is started, and the cold air near the circuit board passes through the first heat dissipation channel 3 and the second heat dissipation channel 4 to cool the heat sink on the circuit board.

[0039] In the prior art, in order to dissipate heat from the circuit board inside the photovoltaic inverter, a cooling fan is usually provided near the circuit board. However, the main function of the cooling fan is to dissipate heat from the front of the circuit board, and it is basically impossible to dissipate heat from the back of the circuit board. The fan module of the photovoltaic inverter of this embodiment extracts the heat from the back of the circuit board by exhausting air to dissipate the heat from the heat dissipation copper bar on the back, thereby forming an internal heat cycle, stirring the heat inside the photovoltaic inverter, and preventing local excessive heat from affecting the reliability of the photovoltaic inverter. In other embodiments, multiple cooling fans can also be provided inside the photovoltaic inverter to dissipate heat from the front of the circuit board.

[0040] The photovoltaic inverter of this embodiment has at least the following advantages:

[0041] (1) By providing the first heat dissipation channel 3 and the second heat dissipation channel 4, it is possible to effectively avoid the phenomenon of local heat accumulation on the back of the circuit board, thereby affecting the reliability of the photovoltaic inverter.

[0042] (2) High flexibility, the shape of the windshield can be flexibly adjusted according to the distribution of the heat dissipation copper bar and components to adjust the layout of the first heat dissipation channel 3 or the second heat dissipation channel 4;

[0043] (3) The heat dissipation efficiency can be improved by enlarging the opening area of ​​the first wind shield 31 and / or the second wind shield 41 or increasing the length range of the first wind shield 31 and / or the second wind shield 41.

[0044] As shown in this specification and claims, the terms "comprises" and "include" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list, and the method or device may also include other steps or elements. The term "or" as used herein includes any combination of one or more of the relevant listed items.

[0045] It should be noted that, unless otherwise specified, when a feature is referred to as being "fixed" or "connected" to another feature, it may be directly fixed or connected to the other feature, or it may be indirectly fixed or connected to the other feature. In addition, the descriptions of up, down, left, right, etc. used in the present invention are only relative to the relative positional relationship of the components of the present invention in the drawings.

[0046] The above embodiment is only for illustrating the technical concept and features of the present invention, and is a preferred embodiment. Its purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention. Any equivalent transformation or modification made according to the principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A photovoltaic inverter, comprising a housing having an inner cavity and a first circuit board located in the inner cavity, components are arranged on the front of the first circuit board, a heat sink for dissipating heat of the components is arranged on the back of the first circuit board, the components and the heat sink correspond to and are connected to each other, characterized in that: The photovoltaic inverter also includes a plurality of first wind shields, the inner cavity is separated into a first heat dissipation channel by the first wind shields and the back of the first circuit board, and the heat sink is exposed in the first heat dissipation channel; the photovoltaic inverter also includes a fan module arranged in the inner cavity, the fan module includes a fan and has an air inlet or an air outlet, and one of the air inlet and the air outlet is connected to the first heat dissipation channel.

2. The photovoltaic inverter according to claim 1, characterized in that: The fan module also includes a base, the fan is located on the base, the air inlet side of the fan faces the inner cavity of the base, and the air outlet side of the fan faces the first heat dissipation channel.

3. The photovoltaic inverter according to claim 2, characterized in that: The base is provided with the air inlet, which includes a first air inlet and a second air inlet. The first heat dissipation channel is connected with the air inlet side of the fan through the first air inlet.

4. The photovoltaic inverter according to claim 3, characterized in that: The heat sink is a copper heat sink, which is welded on the back of the first circuit board.

5. The photovoltaic inverter according to claim 4, characterized in that: The first wind shield is bonded to the bottom plate of the shell or the first circuit board; the first wind shield is made of insulating soft material.

6. The photovoltaic inverter according to claim 3, characterized in that: The photovoltaic inverter also includes a second circuit board, a support plate for supporting the second circuit board, and a plurality of second wind shields. Components are provided on the front of the second circuit board, and a heat sink for dissipating heat from the components is provided on the back of the second circuit board. The components and the heat sink correspond to and are connected to each other. The inner cavity is divided into a second heat dissipation channel by the second wind shield, the support plate, and the back of the second circuit board. The heat sink is exposed in the second heat dissipation channel, and the second heat dissipation channel is connected to the second air inlet.

7. The photovoltaic inverter according to claim 6, characterized in that: The second heat dissipation channel is connected to the air inlet side of the fan through the second air inlet; the heat dissipation seat is a heat dissipation copper bar, and the heat dissipation copper bar is welded on the back side of the second circuit board.

8. The photovoltaic inverter according to claim 7, characterized in that: The second air inlet is located above the first air inlet and the first air inlet is connected to the second air inlet, and the air outlet side of the fan is located between the first air inlet and the second air inlet.

9. The photovoltaic inverter according to claim 7, characterized in that: The second wind shield is bonded to the support plate or the second circuit board; the second wind shield is made of insulating soft material.

10. The photovoltaic inverter according to claim 7, characterized in that: A first sealing strip is provided between the first air inlet and the first wind shield; and a second sealing strip is provided between the second air inlet and the second wind shield.

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