Photovoltaic string type inverter

Abstract

The invention belongs to the technical field of photovoltaic inverters, and provides a photovoltaic string type inverter which comprises a string type inverter body, and a control screen is installed on the front end face of the string type inverter body. The heat dissipation seats are installed on the two side walls of the string type inverter body, a plurality of heat dissipation grids are arranged on the side walls of the heat dissipation seats, flow guide plates are fixed in the heat dissipation grids, filter plates are installed in the heat dissipation seats, and the filter plates are attached to the side walls of the flow guide plates; a scraping assembly; through the arrangement of the heat dissipation base, the cleaning and scraping assembly and the filter plate, the scraping plate can periodically clean the filter plate and the flow guide plate under the control of the driving assembly, sand and dust accumulated on the filter plate and the flow guide plate are removed in time, and it is ensured that the heat dissipation grating, the filter plate and the flow guide plate always keep good air permeability and flow guide performance; the problem that heat dissipation is blocked due to sand and dust accumulation is effectively solved.

Description

Technical Field

[0001] The invention belongs to the technical field of photovoltaic inverters, in particular to a photovoltaic string inverter. Background Art

[0002] Desert areas are ideal locations for building large-scale photovoltaic power stations due to their abundant light resources. However, the desert environment is characterized by high temperature, dryness, and heavy dust, which poses many challenges to the normal operation of photovoltaic string inverters. High temperatures can affect the performance and life of electronic components inside the inverter, reduce their conversion efficiency, and may even cause component damage. In order to cope with high temperature issues, inverters are usually equipped with heat dissipation systems, such as heat sinks, heat sinks, and heat sinks, which dissipate heat through heat conduction and air convection to maintain a suitable temperature inside the inverter.

[0003] The heat dissipation grid of existing photovoltaic string inverters is prone to dust accumulation, which makes it difficult for the heat generated inside the inverter to be dissipated in time, causing the internal temperature to rise.

[0004] High temperature will not only affect the performance of electronic components, such as reducing the carrier mobility of semiconductor devices and increasing resistance loss, but may also cause thermal stress problems in components, accelerate component aging and damage, shorten the service life of the inverter, and reduce the power generation efficiency and stability of the entire photovoltaic power station.

[0005] To this end, those skilled in the art have proposed a photovoltaic string inverter to solve the problems raised by the background technology. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a photovoltaic string inverter to solve the problem that the heat dissipation grid of the photovoltaic string inverter in the prior art is prone to accumulation of sand and dust, which makes it difficult to dissipate the heat generated inside the inverter in time, thereby causing the internal temperature to rise.

[0007] A photovoltaic string inverter comprises: a string inverter body, wherein a control panel is installed on the front end surface of the string inverter body;

[0008] A heat sink, the heat sink is installed on both side walls of the string inverter body, a plurality of heat sink grilles are provided on the side walls of the heat sink, a guide plate is fixed inside the heat sink grille, and a filter plate is installed inside the heat sink, and the filter plate is fitted with the side wall of the guide plate;

[0009] The scraping assembly comprises a driving assembly, a moving rod and a scraper. Several scrapers are fixed on the side wall of the moving rod. The scrapers are adapted to the filter plate and the guide plate. The driving assembly controls the displacement of the scrapers along the surface of the filter plate and the guide plate.

[0010] Preferably, the drive assembly includes a drive plate, a servo motor, a screw, a slide, an electric push rod and a control plate; the drive plate is fixed to the inner wall of the heat sink, the inner wall of the drive plate is opened in a slide groove, the screw rod is rotated in the slide groove, the servo motor controls the rotation of the screw rod, the screw rod is threaded with the slide, the electric push rod is fixedly installed on the outer surface of the slide, the telescopic end of the electric push rod is connected to the telescopic rod, one end of the telescopic rod is fixedly connected to a connecting plate, the bottom surface of the connecting plate is connected to the moving rod, the control plate is installed on the upper surface of the drive plate, and the servo motor and the electric push rod are electrically connected to the control plate.

[0011] Preferably, a driven tooth is installed on the circumference of the screw rod, the output end of the servo motor is connected to the slide groove, the output end of the servo motor is connected to a driving tooth, and the driving tooth is meshed with the driven tooth.

[0012] Preferably, a fixing seat is fixed to the inner wall of the heat dissipation seat, and the filter plate is limitedly installed on the bottom surface of the fixing seat.

[0013] Preferably, a spring groove is provided on the bottom surface of the fixed seat, a memory spring is connected to the inner surface of the spring groove, one end of the memory spring is connected to a limiting block, the position of the limiting block corresponds to the filter plate, a pull rod is fixedly connected to the top surface of the limiting block, and the pull rod passes through the spring groove.

[0014] Preferably, a heat sink and a plurality of heat sinks are installed on the inner wall of the string inverter body, and the positions of the heat sinks correspond to the heat sink seats.

[0015] Preferably, both side walls of the heat sink are fixedly connected with embedded plates, a positioning plate is fixed to the bottom surface of the heat sink, bolts are installed between the positioning plate and the outer wall of the string inverter body, and the embedded plate is snapped into the outer wall of the string inverter body.

[0016] Preferably, a hanging plate is fixedly connected to the upper surface of the outer wall of the string inverter body, and a plurality of mounting holes penetrate the surface of the hanging plate.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The present invention provides a heat sink, a scraper assembly and a filter plate, so that the scraper can periodically clean the filter plate and the guide plate under the control of the drive assembly, and promptly remove the dust accumulated thereon, thereby ensuring that the heat dissipation grille, the filter plate and the guide plate always maintain good air permeability and flow conductivity, effectively solving the problem of heat dissipation obstruction caused by dust accumulation, ensuring that the inverter can also operate stably in a dusty environment, maintaining normal working efficiency, extending the service life of the equipment, and reducing power generation losses caused by overheating shutdown. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1It is a schematic diagram of the overall structure of the present invention;

[0020] Figure 2 It is a schematic diagram of the internal cross-sectional structure of the present invention;

[0021] Figure 3 for Figure 2 A partial enlarged view of part A;

[0022] Figure 4 It is a three-dimensional structural schematic diagram of the scraper;

[0023] Figure 5 Schematic diagram of the internal structure of the drive component.

[0024] In the figure:

[0025] 1. String inverter body; 2. Control panel; 3. Heat sink; 4. Heat sink grille; 401. Guide plate; 5. Positioning plate; 501. Embedded plate; 6. Bolt; 7. Heat sink; 8. Fixed seat; 9. Filter plate; 10. Moving rod; 11. Scraper; 1101. Cleaning surface; 12. Drive plate; 13. Servo motor; 14. Screw; 15. Active gear; 16. Driven gear; 17. Slide; 18. Electric push rod; 19. Telescopic rod; 20. Connecting plate; 21. Control board; 22. Spring slot; 23. Memory spring; 24. Pull rod; 25. Limit block; 26. Hanging plate; 27. Mounting hole. DETAILED DESCRIPTION

[0026] The following is a further detailed description of the embodiments of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0027] Embodiment 1: As shown in the attached Figure 1 and Figure 2 As shown: The present invention provides a photovoltaic string inverter, comprising a string inverter body 1, a heat sink 3 and a scraping assembly;

[0028] A control panel 2 is installed on the front end of the string inverter body 1;

[0029] As attached Figure 2 and Figure 3As shown: the heat sink 3 is installed on the two side walls of the string inverter body 1, and a number of heat sink grilles 4 are provided on the side walls of the heat sink 3, and a guide plate 401 is fixed inside the heat sink grille 4, and a filter plate 9 is installed inside the heat sink 3, and the filter plate 9 is in contact with the side wall of the guide plate 401; the heat sink grille 4 helps the heat inside the inverter to exchange heat with the outside air; when the inverter generates heat during operation, the heat is transferred to the heat sink 3 through heat conduction, and then at the heat sink grille 4, the hot air rises, and the outside cold air enters through the grille, forming natural convection, thereby taking away part of the heat. At the same time, the guide plate 401 in the heat sink 3 can guide the direction of air flow, making it more efficient in heat dissipation, and can prevent dust and other impurities from directly impacting the key components inside the inverter; when foreign matter such as sand and dust enters the heat sink 3, the filter plate 9 can block most of the sand and dust to prevent it from entering the inside of the inverter.

[0030] As attached Figure 4 As shown: the scraping assembly includes a driving assembly, a moving rod 10, and a scraper 11. A plurality of scrapers 11 are fixed to the side wall of the moving rod 10. The scrapers 11 are adapted to the filter plate 9 and the guide plate 401. The driving assembly controls the scraper 11 to move along the surface of the filter plate 9 and the guide plate 401. The scraper 11 is a triangular plate structure. The scraper 11 is divided into a top surface, a fitting surface, and a scraping surface 1101. The fitting surface fits the surface of the filter plate 9, and the scraping surface 1101 is perpendicular to the guide plate 401. The scraper 11 is a triangular plate structure. The angular plate structure is divided into three surfaces: the top surface, the fitting surface and the cleaning surface 1101; the fitting surface is tightly fitted with the surface of the filter plate 9, and when the scraper 11 moves, the sand and dust attached to the filter plate 9 can be effectively scraped off; the cleaning surface 1101 is perpendicular to the guide plate 401, and when the scraper 11 moves on the guide plate 401, the cleaning surface 1101 can remove the sand and dust accumulated on the guide plate 401, ensuring that the air guide effect of the guide plate 401 is not affected, thereby maintaining the heat dissipation efficiency of the heat sink 3.

[0031] The driving assembly includes a driving plate 12, a servo motor 13, a screw 14, a slide 17, an electric push rod 18 and a control board 21; the driving plate 12 is fixed to the inner wall of the heat sink 3, the inner wall of the driving plate 12 is provided with a slide groove, the screw rod 14 is rotated in the slide groove, the servo motor 13 controls the screw rod 14 to rotate, the screw rod 14 is threadedly matched with the slide 17, the electric push rod 18 is fixedly installed on the outer surface of the slide 17, the telescopic end of the electric push rod 18 is connected to the telescopic rod 19, one end of the telescopic rod 19 is fixedly connected to a connecting plate 20, the bottom surface of the connecting plate 20 is connected to the moving rod 10, the control board 21 is installed on the upper surface of the driving plate 12, and the servo motor 13 and the electric push rod 18 are both electrically connected to the control board 21.

[0032] As attached Figure 5 As shown: a driven tooth 16 is also installed on the side of the screw rod 14, the output end of the servo motor 13 is connected to the slide groove, and the output end of the servo motor 13 is connected to a driving tooth 15, and the driving tooth 15 is meshed with the driven tooth 16.

[0033] A heat sink 7 and a plurality of heat sinks are installed on the inner wall of the string inverter body 1 , and the position of the heat sink 7 corresponds to the heat sink seat 3 .

[0034] A hanging plate 26 is fixedly connected to the upper surface of the outer wall of the string inverter body 1 , and a plurality of mounting holes 27 penetrate through the surface of the hanging plate 26 .

[0035] As can be seen from the above, after the servo motor 13 is started, the active teeth 15 at the output end thereof drive the driven teeth 16 on the peripheral side of the screw rod 14 to rotate, thereby causing the screw rod 14 to rotate in the slide groove on the inner wall of the driving plate 12. Since the screw rod 14 and the slide seat 17 are threadedly matched, the rotation of the screw rod 14 drives the slide seat 17 to move linearly along the slide groove.

[0036] The electric push rod 18 fixedly mounted on the outer surface of the slide 17 is connected to the moving rod 10 through the telescopic rod 19 and the connecting plate 20. When the scraper 11 is needed to clean the filter plate 9, the control board 21 controls the electric push rod 18 to extend, push the scraper 11 down, make its contact surface contact with the filter plate 9, drive the scraper 11 to move along the surface of the filter plate 9, and realize the cleaning operation of the filter plate 9.

[0037] After the cleaning of the filter plate 9 is completed, the scraper 11 is moved to the top of the guide plate 401 through the rotation of the servo motor 13, and then the electric push rod 18 is extended again to make the cleaning surface 1101 of the scraper 11 contact the guide plate 401, and then the servo motor 13 is started again to drive the scraper 11 to move along the surface of the guide plate 401 to complete the cleaning operation of the guide plate 401; during the whole process, the control board 21 accurately controls the action of the servo motor 13 and the electric push rod 18 according to the preset program and the information fed back by the sensor, so as to realize the automatic control of the scraper 11, ensure that the filter plate 9 and the guide plate 401 can be cleaned regularly, maintain the good heat dissipation performance of the heat sink 3, and ensure that the inverter can operate stably and reliably even in harsh environments.

[0038] The control algorithm for cleaning the filter plate 9 and the guide plate 401 is as follows:

[0039] System initialization and parameter setting:

[0040] The control board 21 is initialized to ensure normal communication with the servo motor 13 , the electric push rod 18 and the position sensor, which is located at the connection between the scraper 11 and the moving rod 10 .

[0041] According to the actual size and structure of the heat sink 3, the filter plate 9 and the guide plate 401, the following parameters are determined:

[0042] The extension and retraction speed V of the electric push rod 18 ep and V er, the unit is mm / s, and the speed value is set according to the actual test of the electric push rod 18;

[0043] The pitch P of the screw rod 14 is in millimeters, which is an inherent parameter of the screw rod and can be obtained from the specification manual of the screw rod.

[0044] The transmission ratio i of the gear set, the tooth number ratio of the driving tooth 15 to the driven tooth 16 is Z2 / Z1, then i=Z2 / Z1, which is calculated by the number of teeth of the gear.

[0045] The length L of the filter plate 9 f and the length L of the guide plate 401 d , in millimeters, obtained through actual measurement.

[0046] The control panel 21 sends an extension command to the electric push rod 18, and the electric push rod 18 extends at a speed V ep Start stretching.

[0047] At the same time, the control board 21 continuously monitors the feedback signal of the position sensor on the electric push rod 18. When the extended displacement of the electric push rod 18 reaches a predetermined value (this value is determined according to the equipment structure and the initial relative position of the scraper and the filter plate), the extension action of the electric push rod 18 is stopped. At this time, the scraper 11 should be just above the starting cleaning position of the filter plate 9.

[0048] The control panel 21 starts the servo motor 13 to make it rotate in the forward direction at a predetermined speed (unit: revolutions per minute), and drives the screw rod 14 to rotate through the driving gear 15 and the driven gear 16 .

[0049] The rotation of the screw rod 14 drives the slide seat 17 to move linearly along the slide groove of the driving plate 12, thereby driving the scraper 11 to move along the surface of the filter plate 9 from one end to the other end to perform a scraping operation.

[0050] The control panel 21 monitors the moving position of the scraper 11 on the filter plate 9 in real time through the displacement sensor. When the moving distance of the scraper 11 reaches the length L of the filter plate 9, f When the servo motor 13 is controlled to stop rotating, the one-way scraping of the filter plate 9 is completed.

[0051] To ensure the scraping effect, the number of times is preset; for example, three times of back and forth scraping; the servo motor 13 is controlled to reverse, so that the scraper 11 returns to the starting end, and then rotates forward again to scrape, and this process is repeated until the set number of scraping times is reached. The speed of each reverse and forward rotation can be the same, and can also be fine-tuned according to actual conditions to optimize the scraping effect and equipment life.

[0052] The scraper 11 moves to the starting position of the guide plate 401:

[0053] After the cleaning of the filter plate 9 is completed, the control panel 21 sends a retraction command to the electric push rod 18, and the electric push rod 18 starts to retract at a speed.

[0054] The control panel 21 is adjusted according to the preset retracted displacement value (L er0 , which value is determined according to the relative position of the filter plate 9 and the guide plate 401 and the equipment structure), and the retracted position of the electric push rod 18 is monitored by the position sensor. When the predetermined distance is reached, the retracting action of the electric push rod 18 is stopped. At this time, the scraper 11 should be above the starting position of the guide plate 401 for scraping, and keep a certain safety distance from the surface of the guide plate 401 to avoid collision.

[0055] The control panel 21 starts the servo motor 13 again, adjusts the rotation speed of the servo motor 13 to (unit: revolutions per minute) according to the inclination angle and length of the guide plate 401, and determines the appropriate rotation direction (this direction must ensure that the scraper 11 can move stably along the inclination direction of the guide plate 401), driving the scraper 11 to move along the surface of the guide plate 401 from one end to the other to perform a scraping operation.

[0056] Similarly, the control panel 21 monitors the moving position of the scraper 11 on the guide plate 401 in real time through the displacement sensor. When the moving distance of the scraper 11 reaches the length L of the guide plate 401, d When the servo motor 13 is controlled to stop rotating, the one-way cleaning of the guide plate 401 is completed.

[0057] The number of times the guide plate 401 is cleaned can be set as needed, for example, two times of back and forth cleaning; the above cleaning process is repeated until the set number of cleaning times is reached. During the cleaning process of the guide plate 401, since the inclination angle of the guide plate 401 will affect the force of the scraper 11, this factor needs to be considered when determining the speed and rotation direction of the servo motor 13 to ensure that the scraper 11 can stably fit the surface of the guide plate 401Z for cleaning, and at the same time avoid damage or significant wear of the scraper 11 due to uneven force.

[0058] After the guide plate 401 is cleaned, the control panel 21 finally sends a signal to the electric push rod 18 to completely retract it to the initial position, and at the same time resets the servo motor 13 to the initial state to prepare for the next cleaning operation.

[0059] The system enters standby mode, waiting for the next scraping instruction or automatically starting the next scraping cycle according to the preset time interval.

[0060] Embodiment 2: Both side walls of the heat sink 3 are fixedly connected with an embedded plate 501 , a positioning plate 5 is fixed to the bottom surface of the heat sink 3 , bolts 6 are installed between the positioning plate 5 and the outer wall of the string inverter body 1 , and the embedded plate 501 is snapped into the outer wall of the string inverter body 1 .

[0061] As can be seen from the above, the embedded plates 501 on the two side walls of the heat sink 3 are inserted into the outer wall of the string inverter body 1. This inserted structure can preliminarily locate the installation position of the heat sink 3, making its connection with the string inverter body 1 tighter and more accurate. At the same time, the positioning plate 5 on the bottom of the heat sink 3 is fixed to the outer wall of the string inverter body 1 by bolts 6. The bolts 6 provide a reliable fastening force to ensure that the heat sink 3 will not be displaced or loosened during the operation of the inverter, thereby ensuring the heat conduction efficiency between the heat sink 3 and the string inverter body 1 and the stability of the overall structure, which is conducive to the long-term stable operation of the inverter and the maintenance of the heat dissipation performance.

[0062] Embodiment three: A fixing seat 8 is fixed on the inner wall of the heat dissipation seat 3, and a filter plate 9 is limitedly installed on the bottom surface of the fixing seat 8; a spring groove 22 is opened on the bottom surface of the fixing seat 8, and a memory spring 23 is connected to the inner surface of the spring groove 22, and one end of the memory spring 23 is connected to a limiting block 25, and the position of the limiting block 25 corresponds to the filter plate 9, and a pull rod 24 is fixedly connected to the top surface of the limiting block 25, and the pull rod 24 passes through the spring groove 22.

[0063] It can be seen from the above that when the filter plate 9 is impacted by sand and dust or when it is installed or removed, the memory spring 23 and the limit block 25 can fix the filter plate 9 to ensure its stable position and the filtering effect; the pull rod 24 runs through the spring groove 22, so that when the filter plate 9 needs to be replaced or cleaned, the operator can pull the pull rod 24 to release the restriction of the limit block 25 on the filter plate 9, thereby easily taking out the filter plate 9 for maintenance.

[0064] The embodiments of the present invention are provided for the purpose of illustration and description. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A photovoltaic string inverter, characterized in that: include: A string inverter body (1), wherein a control panel (2) is installed on the front end surface of the string inverter body (1); A heat sink (3), the heat sink (3) being mounted on two side walls of a string inverter body (1), a plurality of heat sink grilles (4) being provided on the side walls of the heat sink (3), a guide plate (401) being fixed inside the heat sink grilles (4), and a filter plate (9) being mounted inside the heat sink (3), the filter plate (9) being in contact with the side walls of the guide plate (401); A scraping assembly comprises a driving assembly, a moving rod (10), and a scraper (11); a plurality of the scrapers (11) are fixed to the side wall of the moving rod (10); the scrapers (11) are adapted to the filter plate (9) and the guide plate (401); and the driving assembly controls the displacement of the scrapers (11) along the surface of the filter plate (9) and the guide plate (401).

2. A photovoltaic string inverter as claimed in claim 1, characterized in that: The driving assembly comprises a driving plate (12), a servo motor (13), a screw rod (14), a slide seat (17), an electric push rod (18) and a control plate (21); the driving plate (12) is fixed to the inner wall of the heat sink (3); the inner wall of the driving plate (12) is provided with a slide groove; the screw rod (14) is rotatably connected in the slide groove; the servo motor (13) controls the screw rod (14) to rotate; the screw rod (14) is threadedly matched with the slide seat (17); the electric push rod (18) is fixedly installed on the outer surface of the slide seat (17); the telescopic end of the electric push rod (18) is connected to the telescopic rod (19); one end of the telescopic rod (19) is fixedly connected to a connecting plate (20); the bottom surface of the connecting plate (20) is connected to the moving rod (10); the control plate (21) is installed on the upper surface of the driving plate (12); the servo motor (13) and the electric push rod (18) are both electrically connected to the control plate (21).

3. A photovoltaic string inverter as claimed in claim 2, characterized in that: A driven tooth (16) is also installed on the circumferential side of the screw rod (14); the output end of the servo motor (13) is connected to the slide groove; the output end of the servo motor (13) is connected to a driving tooth (15); and the driving tooth (15) meshes with the driven tooth (16).

4. A photovoltaic string inverter as claimed in claim 3, characterized in that: A fixing seat (8) is fixed on the inner wall of the heat dissipation seat (3), and the filter plate (9) is limitedly mounted on the bottom surface of the fixing seat (8).

5. A photovoltaic string inverter as claimed in claim 4, characterized in that: A spring groove (22) is provided on the bottom surface of the fixing seat (8), a memory spring (23) is connected to the inner surface of the spring groove (22), one end of the memory spring (23) is connected to a limit block (25), the position of the limit block (25) corresponds to the filter plate (9), the top surface of the limit block (25) is fixedly connected to a pull rod (24), and the pull rod (24) passes through the spring groove (22).

6. A photovoltaic string inverter as claimed in claim 1, characterized in that: The inner wall of the string inverter body (1) is provided with a heat sink (7) and a plurality of heat sinks, and the position of the heat sink (7) corresponds to the heat sink seat (3).

7. A photovoltaic string inverter as claimed in claim 1, characterized in that: Both side walls of the heat sink (3) are fixedly connected with an embedded plate (501), a positioning plate (5) is fixed to the bottom surface of the heat sink (3), bolts (6) are installed between the positioning plate (5) and the outer wall of the string inverter body (1), and the embedded plate (501) is snapped into the outer wall of the string inverter body (1).

8. A photovoltaic string inverter as claimed in claim 1, characterized in that: A hanging plate (26) is fixedly connected to the upper surface of the outer wall of the string inverter body (1), and a plurality of mounting holes (27) penetrate the surface of the hanging plate (26).

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