Photovoltaic inverter

Abstract

The utility model discloses a photovoltaic inverter which comprises a main box body and a sealing box body, a circuit module is arranged in the main box body, the main box body and / or the sealing box body are / is provided with wiring terminals, the wiring terminals are electrically connected with the circuit module, the sealing box body comprises a wire threading plate, and the wire threading plate is arranged in the main box body. The wire threading plate is provided with a wire threading hole for a cable to enter the sealing box body to be connected with the wiring terminal, the sealing box body further comprises a sealing pipe extending outwards from the wire threading plate, the sealing pipe is provided with a pipe cavity for the cable to penetrate through, the inner end face of the sealing pipe is connected with the wire threading plate in a sealing mode and surrounds the wire threading hole, and the sealing pipe is provided with a pipe cavity for the cable to penetrate through. And the threading hole is communicated with a pipe cavity of the sealing pipe. The photovoltaic inverter of the utility model has the advantages of good sealing performance and convenient installation.

Description

Technical Field

[0001] The utility model 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 alternating current (AC) at the mains frequency, which can be fed back to the commercial power transmission system or used for off-grid power grids.

[0003] A photovoltaic inverter consists of a main housing and a sealed housing. A terminal block is installed between the main housing and the sealed housing. One end of the terminal block connects to the power circuit board inside the main housing, and the other end connects to the grid or load. When the terminal block is connected to the grid or load via a cable, one end of the cable will emerge from the interior of the sealed housing. At this time, the seal between the cable and the sealed housing must be ensured. Currently, there are two implementation methods. The first option is to use a "pagoda-shaped" seal between the sealed housing and the cable. The thickness of the cable determines the required ring layer of the seal. After the seal is cut, the cable is passed through the seal to achieve sealing. The second option uses a two-part extrusion seal to achieve sealing. The seal consists of a first seal and a second seal. In specific operation, the first seal is first fixed to the support frame of the sealed housing. After the cable is fixed, the second seal is placed on the support frame. The lid of the sealed housing is locked and the seal is deformed by the extrusion of the lid to achieve sealing.

[0004] Regarding the above two implementation methods, the first solution has a better sealing effect because the "pagoda" structure is double-sided and can achieve double sealing. The second solution is easier to install and saves effort, but the sealing effect is poor. The material of the sealing plate is silicone, and the deformation direction of silicone after extrusion is uncontrollable. Utility Model Content

[0005] In order to solve the above technical problems, the utility model provides a photovoltaic inverter with good sealing performance and convenient installation.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A photovoltaic inverter comprises a main box and a sealed box, wherein the main box has a built-in circuit module, and the main box and / or the sealed box are provided with wiring terminals, wherein the wiring terminals are electrically connected to the circuit module, and the sealed box comprises a threading plate, wherein the threading plate is provided with threading holes for cables to enter the sealed box to connect to the wiring terminals, and the sealed box further comprises a sealing tube extending outward from the threading plate, wherein the sealing tube has a lumen for cables to pass through, and the inner end surface of the sealing tube is sealedly connected to the threading plate and surrounds the threading hole, and the threading hole is connected to the lumen of the sealing tube.

[0008] In a preferred embodiment, the photovoltaic inverter further comprises a sealing sleeve, wherein a first end portion of the sealing sleeve is sleeved on the sealing tube, and a second end portion of the sealing sleeve is sleeved on a cable passing through the sealing tube.

[0009] In a preferred embodiment, the sealing sleeve is elastic or shrinkable.

[0010] In a preferred embodiment, the sealing sleeve is a cold shrink sleeve.

[0011] In a preferred embodiment, a plurality of wire threading holes are provided on the wire threading plate, each of the wire threading holes is connected to a sealing tube, a cable is passed through each wire threading hole and the corresponding sealing tube, and the plurality of cables have a bundled portion that converges together, and the bundled portion is located outside the sealing box.

[0012] In a preferred embodiment, the plurality of cables are bundled together by a bundler, the first end of the bundler has a plurality of first sleeve portions, each of the first sleeve portions is for a cable to pass through, and the second end of the bundler has a second sleeve portion that can accommodate the plurality of cables, and the inner diameter of the second sleeve portion is larger than the inner diameter of the first sleeve portion.

[0013] In a more preferred embodiment, the photovoltaic inverter further includes a sheath, and the sheath is fixedly connected to the bundle combiner.

[0014] In a more preferred embodiment, a sealing rubber gasket is provided between the threading plate and the sealing tube.

[0015] In a preferred embodiment, the photovoltaic inverter further includes a cover, and the sealing tube is located on the outside of the cover.

[0016] In a preferred embodiment, the power of the photovoltaic inverter is greater than 100KW.

[0017] The present invention adopts the above solution, which has the following advantages compared with the prior art:

[0018] The photovoltaic inverter of the present invention has a plurality of threading holes for the cables to pass through on the threading plate. One end of the cable is connected to the terminal block, and the other end directly passes through the threading hole and the tube cavity, which makes cable threading more convenient. The cable is sealed by a sealing tube arranged on the outside of the sealing box, and the sealing effect is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 is a perspective view of a photovoltaic inverter according to an embodiment of the present utility model;

[0021] Figure 2 This is a front view of a photovoltaic inverter according to an embodiment of the present utility model;

[0022] Figure 3 This is a three-dimensional diagram of the threading plate.

[0023] in,

[0024] 1. Sealed box; 11. Cavity;

[0025] 2. Terminal block; 3. Cable; 4. Cover; 5. Threading plate; 51. Threading hole; 52. Sealing tube; 53. Main body; 6. Sealing sleeve; 7. Sealing pad; 8. Connector; 9. Sheath. DETAILED DESCRIPTION

[0026] The following describes in detail preferred embodiments of the present invention in conjunction with the accompanying drawings to make the advantages and features of the present invention more easily understood by those skilled in the art. It should be noted that the description of these embodiments is intended to facilitate understanding of the present invention and 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 may be combined with each other as long as they do not conflict with each other.

[0027] The present embodiment provides a photovoltaic inverter that can convert the variable DC voltage generated by the photovoltaic solar panel into an AC power inverter with a mains frequency, which can be fed back to the commercial power transmission system or used by an off-grid power grid. The power of the photovoltaic inverter of this embodiment is greater than 100KW. The photovoltaic inverter includes a main box (not shown in the figure) and a sealed box 1. A circuit module is provided inside the main box, and the circuit module includes a power circuit board. A terminal block 2 is provided between the main box and the sealed box 1. One end of the terminal block 2 is connected to the power circuit board in the main box, and the other end is connected to the load or power grid outside the sealed box 1 through a cable.

[0028] Further, refer to Figures 1 to 3 As shown, the photovoltaic inverter also includes a cover 4, a threading plate 5, and a sealing sleeve 6. Furthermore, the cover 4 is used to seal the cavity 11 of the sealed box 1. The threading plate 5 is disposed within the cavity 11 of the sealed box 1 and is provided with a plurality of threading holes 51 for cables 3 to enter the sealed box 1 for connection to the terminal blocks 2.

[0029] Reference Figure 3 As shown, the sealed box 1 further includes a sealing tube 52 extending outward from the threading plate 5. The sealing tube 52 has a lumen for the passage of the cable 3. The inner end surface of the sealing tube 52 is sealedly connected to the threading plate 5 and surrounds the threading holes 51. The threading holes 51 communicate with the lumen of the sealing tube 52. Each threading hole 51 communicates with a sealing tube 52, and a cable 3 is passed through each threading hole 51 and the corresponding sealing tube 52.

[0030] Furthermore, the sealing sleeve 6 and the sealing tube 52 are located on the outside of the cover body 4, and the sealing sleeve 6 is used to seal between the cable 3 and the threading plate 5. The first end of the sealing sleeve 6 is sleeved on the sealing tube 52, and the second end of the sealing sleeve 6 is sleeved on the cable 3 passing through the sealing tube 52. The sealing sleeve 6 is elastic or can shrink, and the sealing sleeve 6 is specifically a cold shrink sleeve. The working principle of the cold shrink sleeve is to utilize the elastic retraction characteristics of the material. During the installation process, the cold shrink sleeve is first expanded and sleeved on the cable, and then the internal support bar is removed. The sleeve will rely on its own elasticity to shrink to its original outer diameter and tightly wrap the cable. This installation method does not require heating and is easy to operate. The cold shrink sleeve can effectively prevent water and moisture from entering the interior of the box; protect the cable from damage from the external environment, such as moisture, chemical corrosion, etc.; and is used to organize and wrap cables to make them more tidy.

[0031] Furthermore, a sealing tube 52 is provided at the lower end of the main body 53 of the threading plate 5, corresponding to the threading hole 51. The sealing tube 52 and the main body 53 are fixedly connected or integrally formed. Specifically, in this embodiment, the sealing tube 52 is fixedly connected to the main body 53 of the threading plate 5 by welding. In other embodiments, the sealing tube 52 and the main body 53 can also be integrally formed. A sealing rubber gasket 7 is provided between the threading plate 5 and the sealing tube 52 to ensure the sealing between the threading plate 5 and the sealing box 1.

[0032] The cable 3 of this embodiment can be a single-core cable or a multi-core cable. A single-core cable consists of a single metal conductor, which is usually covered with an insulation layer and a sheath layer. A multi-core cable consists of multiple metal conductors, each of which is independently insulated and ultimately covered in a sheath.

[0033] When the cable 3 is a single-core cable, multiple single-core cables are connected to the load or power grid. Specifically, taking four single-core cables as an example, during assembly, first insert the four wires into the sealing sleeve 6, then remove the threading plate 5 from the cavity 11 of the sealing box 1. The threading plate 5 has four threading holes 52 corresponding to the single-core wires. After pressing the cable connection terminal against the wire core, hang it on the terminal and screw it in place. Adjust the position of the threading plate 52 in the cavity 11, move the sealing sleeve 6 to the root of the sealing tube 52, seal the cable 3 with the sealing sleeve 6, and finally lock the cover 4. The entire assembly is complete.

[0034] When the cables 3 are multi-core cables, the cables 3 have a converging portion where they converge, and the converging portion is located outside the sealed box 1. The cables 3 are converging by a converging member 8. The first end of the converging member 8 has multiple first sleeve portions, each for a cable to pass through. The second end of the converging member 8 has a second sleeve portion that can accommodate multiple cables. The inner diameter of the second sleeve portion is larger than that of the first sleeve portion. The converging member 8 here is also a cold shrink sleeve. Taking a four-core cable as an example, the four cores inside the cable 3 are stripped off on site. The multi-core cable is passed from the second end of the bundle 8 to the first end. The cable 3 is then passed through the lumen of the sealing tube 52. The threading plate 5 is removed from the cavity 11, and the four cores are passed through the four threading holes 51 on the main body 53 of the threading plate 5. The cores are compressed with the cable connection terminal and hung on the terminal 2. The position of the threading plate 5 in the cavity 11 is adjusted and the cable is fixed by screwing. The sealing sleeve 6 is passed through the root of the sealing tube 52, and the support strip inside the sealing sleeve 6 is removed. The sealing sleeve 6 retracts to its original outer diameter by its own elasticity, tightly wrapping each core of the cable 3. Finally, the cover 4 is locked, and the entire assembly is completed. The photovoltaic inverter of this embodiment also includes a sheath. When the cable is multi-core, the sheath 9 is fixedly connected to the bundle 8.

[0035] The existing technology is difficult to thread, especially multi-core cables through the sealing plate. Due to the thick wire diameter and the limited space in the inner cavity of the sealing box, the operation is inconvenient, time-consuming and labor-intensive. If the holes in the sealing plate are cut incorrectly on site, sealing will not be achieved, and fireproof mud can only be applied to seal. However, fireproof mud is difficult to achieve long-term effective protection in harsh environments and is arguably meaningless. In this embodiment, the multi-core cables are separated outside the cavity 11 of the sealing box 1. Each cable 3 is individually passed through the threading plate 5, and each cable is individually sealed, effectively avoiding the problem of insufficient inner cavity space. At the same time, there is no need to cut holes, avoiding the problem of uncontrollable sealing caused by cutting errors.

[0036] The photovoltaic inverter of this embodiment has at least the following advantages:

[0037] (1) The photovoltaic inverter of this embodiment has good sealing performance, and there is no need to worry about the common problems of on-site sealing. Specifically, it avoids the use of "pagoda-type" seals, that is, avoids the poor sealing problem caused by manual cutting holes; avoids the poor sealing caused by the use of two-half seals due to pressure deformation, and does not need to use fireproof mud to remedy the sealing problem, truly achieving IP66 level waterproof and dustproof;

[0038] (2) Multi-core wiring is easier, avoiding insufficient space in the inner cavity. Specifically, multi-core cables do not need to be divided inside the cavity. The wires can be separated outside and connected to the AC terminal block through the wire holes of the wire board. This is convenient for operation and avoids the difficulty of wiring when dividing the wires inside the cavity due to the wires being too thick, which makes it difficult to hang them on the studs.

[0039] (3) One design is compatible with a variety of wiring harness situations on site, and is more compatible and inclusive: Whether the site is single-core cable or multi-core cable, only one threading plate is needed. There is no need to prepare multiple threading plates for customers to adapt to single-core, multi-core, and different wire diameters. The threading holes of the threading plate only need to be designed with the maximum aperture to be compatible with various situations.

[0040] As used in this specification and claims, the terms "comprises" and "include" merely indicate the inclusion of the steps and elements specifically identified, and these steps and elements do not constitute an exclusive list; a method or apparatus may also include other steps or elements. The term "and / or" as used herein includes any combination of one or more of the associated listed items.

[0041] 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 indirectly fixed or connected to the other feature. In addition, the terms "upper," "lower," "left," and "right" used in this utility model are only used with respect to the relative positions of the components of the utility model in the accompanying drawings.

[0042] The above embodiment is intended only to illustrate the technical concept and features of the present invention and is a preferred embodiment. Its purpose is to enable those familiar with the art to understand the content of the present invention and implement it accordingly. It is not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made based on the principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A photovoltaic inverter, comprising a main box and a sealed box, wherein the main box has a built-in circuit module, and the main box and / or the sealed box are provided with wiring terminals, wherein the wiring terminals are electrically connected to the circuit module, characterized in that: The sealed box includes a threading plate, which is provided with a threading hole for cables to enter the sealed box to connect to the terminal. The sealed box also includes a sealing tube extending outward from the threading plate, the sealing tube having a lumen for the cables to pass through, the inner end surface of the sealing tube is sealedly connected to the threading plate and surrounds the threading hole, and the threading hole is connected to the lumen of the sealing tube.

2. The photovoltaic inverter according to claim 1, characterized in that: The photovoltaic inverter further includes a sealing sleeve, wherein a first end portion of the sealing sleeve is sleeved on the sealing tube, and a second end portion of the sealing sleeve is sleeved on a cable passing through the sealing tube.

3. The photovoltaic inverter according to claim 2, characterized in that: The sealing sleeve is elastic or can shrink.

4. The photovoltaic inverter according to claim 3, characterized in that: The sealing sleeve is a cold shrink sleeve.

5. The photovoltaic inverter according to claim 2, characterized in that: The threading plate is provided with a plurality of threading holes, each of which is connected to a sealing tube, and a cable is passed through each threading hole and the corresponding sealing tube, and the plurality of cables have a bundled portion that converges together, and the bundled portion is located outside the sealing box.

6. The photovoltaic inverter according to claim 5, characterized in that: The plurality of cables are bundled together through a bundler, the first end of the bundler has a plurality of first sleeve portions, each of which is for a cable to pass through, and the second end of the bundler has a second sleeve portion that can accommodate the plurality of cables, the inner diameter of the second sleeve portion being larger than the inner diameter of the first sleeve portion.

7. The photovoltaic inverter according to claim 6, characterized in that: The photovoltaic inverter further includes a sheath, and the sheath is fixedly connected to the bundle combining component.

8. The photovoltaic inverter according to claim 1, characterized in that: A sealing rubber pad is provided between the threading plate and the sealing tube.

9. The photovoltaic inverter according to claim 1, characterized in that: The photovoltaic inverter further includes a cover, and the sealing tube is located outside the cover.

10. The photovoltaic inverter according to claim 1, characterized in that: The power of the photovoltaic inverter is greater than 100KW.

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