CN115347802A

CN115347802A - Three-phase off-grid inverter overload protection device

Info

Publication number: CN115347802A
Application number: CN202210888376.5A
Authority: CN
Inventors: 王建波
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-07-27
Filing date: 2022-07-27
Publication date: 2022-11-15

Abstract

The invention discloses an overload protection device for a three-phase off-grid inverter, which relates to the technical field of overload protection of inverters and comprises a device shell, an overhaul board and a uniform heat dissipation mechanism, wherein a circuit board is installed on the inner wall of the side part of the device shell, a control processor, a current detector and a voltage detector are fixedly arranged on the circuit board, the side part of the overhaul board is provided with a ventilation opening, and a dustproof net is installed in the ventilation opening. According to the invention, when the double-shaft extension motor is started, the heat radiation fan can be driven to rotate circumferentially and move back and forth, so that the purpose of uniformly blowing and radiating electronic components in the device is realized, the heat radiation effect is good, the situation that the electronic components are burnt due to overhigh temperature is effectively reduced, the practicability is good, meanwhile, the cleaning brush can be driven to rotate circumferentially to automatically clean the dustproof net, the situation that the dustproof net is blocked by dust is effectively reduced, and the ventilation effect of the dustproof net is ensured.

Description

Three-phase off-grid inverter overload protection device

Technical Field

The invention relates to the technical field of inverter overload protection, in particular to an overload protection device for a three-phase off-grid inverter.

Background

In an alternating-current photovoltaic power generation system, an inverter is an indispensable part and can be generally divided into a grid-connected inverter and an off-grid inverter; the inverter can be divided into a single-phase inverter, a three-phase inverter and a multi-phase inverter according to output classification; in the process of using the three-phase off-grid inverter, an overload protection device is usually arranged to ensure the normal work of the inverter and parts thereof and avoid damage.

Among the prior art, the accessible has appeared and has detected dc-to-ac converter voltage electric current and come the overload protection device that control circuit carried out overload protection, and this kind of overload protection device is when operation, and electronic component such as its inside detector, controller can produce a large amount of heats, and the heat is long-time to be accumulated can the temperature rise in the device, leads to the condition that electronic component is burnt out to appear very easily, and the practicality is relatively poor, for this reason, this application discloses a three-phase is from net dc-to-ac converter overload protection device and satisfies people's demand.

Disclosure of Invention

The present application aims to provide a three-phase off-grid inverter overload protection device to solve the problem that in the prior art, when the device is operated, electronic components such as a detector and a controller inside the device can generate a large amount of heat, the electronic components are easily burnt out due to overhigh temperature for a long time, and the practicability is poor.

In order to achieve the above purpose, the present application provides the following technical solutions: the overload protection device for the three-phase off-grid inverter comprises a device shell, an access panel and a uniform heat dissipation mechanism, wherein a circuit board is installed on the inner wall of the side part of the device shell, a control processor, a current detector and a voltage detector are fixedly arranged on the circuit board, a vent is formed in the side part of the access panel, and a dustproof net is installed in the vent; the uniform heat dissipation mechanism comprises a double-shaft extension motor arranged on the inner side part of the dust screen, one end of an output shaft of the double-shaft extension motor is provided with a connecting lug, the side part of the connecting lug is rotatably provided with a reciprocating screw rod, a reciprocating block is sleeved on the reciprocating screw rod in a threaded manner, the side part of the reciprocating block is provided with a heat dissipation fan, the access panel is provided with a movable self-rotation unit for enabling the reciprocating screw rod to rotate, and the reciprocating block is provided with a limiting guide unit; the output shaft other end of motor is stretched to the biax is connected with and is used for cleaning what the dust screen prevented stifled subassembly, install two on the device shell symmetrically and be used for quick fixation or loosen the convenient dismouting subassembly of access panel.

Preferably, the mobile rotation unit comprises a planetary gear installed at the end of the reciprocating screw rod, a plurality of straight rods are evenly installed at the inner side of the access panel, a fixed rack is installed at one end of each of the straight rods, and the planetary gear is meshed with the fixed rack.

Preferably, the limiting guide unit includes a limiting guide rod mounted on a side of the coupling boss, and an end of the limiting guide rod penetrates the reciprocating block.

Preferably, prevent stifled subassembly including installing the drive bull stick of the motor output shaft other end is stretched to the biax, the tip of drive bull stick runs through the dust screen and installs and connect the rocking arm, the lateral part of connecting the rocking arm has seted up two slide holes, two equal slidable mounting has movable slide bar, two in the slide hole the connecting plate is installed jointly to the one end of activity slide bar, install elasticity extrusion unit on the connecting plate, be provided with the cleaning brush of laminating mutually on the outside portion of dust screen, the cleaning brush passes through fastening unit and installs on the lateral part of connecting plate.

Preferably, the elastic extrusion unit comprises an extrusion spring sleeved on the movable sliding rod, and two ends of the extrusion spring are respectively attached to the connecting rotating arm and the side part of the connecting plate.

Preferably, the fastening unit includes a fastening bolt disposed on the connecting plate, a bolt through hole is formed in a side portion of the connecting plate, a fastening screw hole is formed in a side portion of the cleaning brush, and one end of the fastening bolt penetrates through the bolt through hole and is threadedly mounted in the fastening screw hole.

Preferably, convenient dismouting subassembly is including installing mounting box on the access panel medial part, install on the inner wall of device shell two with mounting box assorted fixed lug, the symmetry is provided with two installation inserted bars, two in the mounting box installation jack, two have all been seted up to fixed lug's lateral part installation jack, two the one end that the installation inserted bar was kept away from each other all extends to the mounting box is outer and run through two respectively the installation jack, install the fixed sleeve on the lateral part inner wall of mounting box, the control bull stick has been cup jointed to the fixed sleeve internal rotation, cup joint on the control bull stick and install the linkage gear, two the one end that the installation inserted bar is close to each other all install with linkage gear engaged with L shape rack, install elasticity gyration unit on the control bull stick, the one end of control bull stick extends to outside the access panel and install locking control unit.

Preferably, the elastic rotation unit includes a torsion spring disposed in the fixing sleeve and sleeved on the control rotating rod, and two ends of the torsion spring are respectively mounted on an inner side wall of the fixing sleeve and an outer peripheral side of the control rotating rod.

Preferably, the locking control unit is including installing hexagonal connecting rod on the control bull stick tip, control knob has been cup jointed in the slip on the hexagonal connecting rod, the anticreep piece is installed to the tip of hexagonal connecting rod, a plurality of locking inserted bars are evenly installed to control knob's lateral part, a plurality of locking jacks have evenly been seted up to the outside portion of access panel, the tip of locking inserted bar extends to in the locking jack, the last elastic reset element that installs of control knob.

Preferably, the elastic reset element comprises a reset spring sleeved on the hexagonal connecting rod, and two ends of the reset spring are respectively attached to the anti-falling block and the side part of the control knob.

In conclusion, the technical effects and advantages of the invention are as follows:

1. in the invention, when the double-shaft extension motor is started, the connecting lug, the reciprocating screw rod and the reciprocating block are used for driving the radiating fan to rotate circumferentially, and meanwhile, under the combined action of the planetary gear and the fixed gear track, the reciprocating screw rod can rotate in the circumferential rotation process, so that the reciprocating block can drive the radiating fan to move back and forth on the circumferential rotation radius, thereby realizing the purpose of uniformly blowing and radiating electronic elements in the device, having good radiating effect, effectively reducing the situation that the electronic elements are burnt due to overhigh temperature and having good practicability;

2. in the invention, when the double-shaft extension motor runs, the cleaning brush is driven to rotate circumferentially through the driving rotating rod, the connecting rotating arm, the movable sliding rod, the connecting plate and the fastening bolt, so that the dust screen is automatically cleaned, and meanwhile, under the elastic action of the extrusion spring, the cleaning brush is extruded and pushed to be always attached to the outer surface of the dust screen for cleaning, so that the cleaning effect is better, the situation that the dust screen is blocked by dust is effectively reduced, and the ventilation effect of the dust screen is ensured;

3. according to the invention, when the control knob is rotated, the two installation insertion rods are driven to move oppositely for avoiding through the hexagonal connecting rod, the control rotating rod, the linkage gear and the L-shaped rack, when the control knob is loosened, the control rotating rod can automatically rotate reversely under the elastic action of the torsion spring, so that the two installation insertion rods can be driven to move oppositely and automatically insert into the installation insertion holes, and the installation box is fixed, thereby realizing the purpose of quickly disassembling and assembling the maintenance panel, and facilitating the maintenance of workers;

4. according to the invention, when the control knob is pulled, the locking insertion rod is driven to move out of the locking insertion hole, at the moment, the control knob is in a loosening state, the control knob can be rotated to carry out dismounting operation, when the control knob is loosened, the control knob is extruded and pushed under the action of the elastic force of the return spring and drives the locking insertion rod to be inserted into the locking insertion hole, the control knob is fixed all the time, the condition that the maintenance plate is loosened and falls off due to careless touch on the control knob is effectively reduced, and the use is more reliable.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic perspective view of an overload protection device for a three-phase off-grid inverter according to an embodiment of the present application;

fig. 2 is a schematic partial sectional structure view of an overload protection device of a three-phase off-grid inverter according to an embodiment of the present application;

fig. 3 is a partially cut-away structural schematic diagram of another view angle of the three-phase off-grid inverter overload protection device according to the embodiment of the application;

FIG. 4 is an enlarged schematic view of a portion of an anti-clogging assembly in an embodiment of the present application;

FIG. 5 is a partial sectional structure schematic diagram of the mounting box in the embodiment of the application;

FIG. 6 is a cross-sectional view of the fixing sleeve according to the embodiment of the present application;

fig. 7 is a partially enlarged schematic structural diagram of a locking control unit in an embodiment of the present application.

In the figure: 1. a device housing; 2. an access panel; 3. a control processor; 4. a current detector; 5. a voltage detector; 6. a dust screen; 7. a double-shaft extension motor; 8. a connection bump; 9. a reciprocating screw rod; 10. moving the block to and fro; 11. a heat radiation fan; 12. a planetary gear; 13. fixing a rack; 14. a limiting guide rod; 15. driving the rotating rod; 16. connecting the rotating arm; 17. a movable slide bar; 18. a connecting plate; 19. a cleaning brush; 20. a compression spring; 21. fastening a bolt; 22. mounting a box; 23. fixing the bump; 24. installing an inserted link; 25. fixing the sleeve; 26. controlling the rotating rod; 27. a linkage gear; 28. an L-shaped rack; 29. a torsion spring; 30. a hexagonal connecting rod; 31. an anti-drop block; 32. a control knob; 33. locking the inserted rod; 34. locking the jack; 35. a return spring.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example (b): referring to fig. 1-7, the overload protection device for the three-phase off-grid inverter comprises a device shell 1, an access panel 2 and a uniform heat dissipation mechanism, wherein a circuit board is installed on the inner wall of the side part of the device shell 1, a control processor 3, a current detector 4 and a voltage detector 5 are fixedly arranged on the circuit board, a ventilation opening is formed in the side part of the access panel 2, and a dust screen 6 is installed in the ventilation opening; the arrangement of the current detector 4 and the voltage detector 5 can detect the voltage and the current of the inverter, and when the phenomenon of overload of the voltage and the current is detected, the control processor 3 can cut off the circuit to carry out overload protection, thereby effectively reducing the condition that the inverter and parts thereof are damaged due to overload.

The uniform heat dissipation mechanism comprises a double-shaft extension motor 7 arranged on the inner side part of the dust screen 6, one end of an output shaft of the double-shaft extension motor 7 is provided with a connecting lug 8, the side part of the connecting lug 8 is rotatably provided with a reciprocating screw rod 9, a reciprocating block 10 is sleeved on the reciprocating screw rod 9 in a threaded manner, the side part of the reciprocating block 10 is provided with a heat dissipation fan 11, the access panel 2 is provided with a movable autorotation unit for enabling the reciprocating screw rod 9 to autorotate, and the reciprocating block 10 is provided with a limited guide unit; the other end of the output shaft of the double-shaft extension motor 7 is connected with an anti-blocking assembly for cleaning the dust screen 6, and two convenient assembly and disassembly assemblies for quickly fixing or loosening the access panel 2 are symmetrically arranged on the device shell 1.

Borrow by above-mentioned structure, when starting biax and stretching motor 7, can drive radiator fan 11 circumferential rotation through connecting lug 8, reciprocal lead screw 9 and reciprocal piece 10 that moves, simultaneously, under the effect of removal rotation unit, reciprocal lead screw 9 can take place the rotation, and then the accessible reciprocates piece 10 and drives radiator fan 11 and carry out round trip movement on circumferential motion's radius, thereby realized can evenly blow radiating purpose to the electronic component in the device, the radiating effect is good, effectively reduce the condition that makes electronic component burnt out because of the high temperature appears, and the practicality is good.

As a preferred embodiment of the present embodiment, the mobile rotation unit comprises a planetary gear 12 mounted on the end of the reciprocating screw rod 9, a plurality of straight rods are uniformly mounted on the inner side of the access panel 2, a fixed rack 13 is mounted on one end of each of the straight rods, and the planetary gear 12 is meshed with the fixed rack 13. The advantage of this setting is that when reciprocating screw 9 is circular rotating, planetary gear 12 also can be circular rotating together, and under the effect of fixed rack 13, planetary gear 12 can take place the rotation in circular rotating's in-process, and then has realized the purpose that can make reciprocating screw 9 synchronous revolution.

As a preferred embodiment of the present embodiment, the restricting guide unit includes a restricting guide 14 installed on a side of the connecting boss 8, the restricting guide 14 being identical to a length direction of the reciprocating screw 9; the end defining the guide rod 14 extends through the shuttle 10. The reciprocating guide device has the advantages that the reciprocating block 10 can only move back and forth and cannot rotate along with the reciprocating screw rod 9, the limiting guide effect is achieved, and the stability in operation is good.

As a preferred embodiment of the present embodiment, the anti-blocking assembly includes a driving rotating rod 15 installed at the other end of the output shaft of the dual-shaft extension motor 7, the end of the driving rotating rod 15 penetrates through the dust screen 6 and is installed with a connecting rotating arm 16, two sliding holes are opened at the side of the connecting rotating arm 16, a movable sliding rod 17 is slidably installed in each of the two sliding holes, a connecting plate 18 is installed at one end of each of the two movable sliding rods 17, an elastic extrusion unit is installed on the connecting plate 18, a cleaning brush 19 attached to the outer side of the dust screen 6 is arranged, and the cleaning brush 19 is installed on the side of the connecting plate 18 through a fastening unit. The advantage of setting up like this, when biax stretched motor 7 operation, can drive cleaning brush 19 circumference through drive bull stick 15, connecting rocking arm 16, activity slide bar 17, connecting plate 18 and fastening unit and rotate, carry out the self-cleaning to dust screen 6, effectively reduce the condition that the dust screen 6 appears and is blockked up by the dust, guaranteed the ventilation effect of dust screen 6.

In this embodiment, the elastic pressing unit includes a pressing spring 20 sleeved on the movable sliding rod 17, and two ends of the pressing spring 20 are respectively attached to the side portions of the connecting rotating arm 16 and the connecting plate 18. The advantage of this setting is, under the elasticity effect of extrusion spring 20, can extrude promotion connecting plate 18 makes cleaning brush 19 carry out the cleaning process in hugging closely the surface of dust screen 6 always, and the cleaning performance is better.

In this embodiment, the fastening unit includes a fastening bolt 21 provided on the connecting plate 18, a bolt through hole is opened at a side portion of the connecting plate 18, a fastening screw hole is opened at a side portion of the cleaning brush 19, and one end of the fastening bolt 21 penetrates through the bolt through hole and is threadedly mounted in the fastening screw hole. The advantage of so setting up is when rotating fastening bolt 21, can fix or loosen cleaning brush 19, and then has realized the purpose that can change cleaning brush 19, has improved the practicality.

As a preferred embodiment of this embodiment, convenient dismouting subassembly is including installing the mounting box 22 on maintenance board 2 inside portion, install two fixed lugs 23 with mounting box 22 assorted on the inner wall of device shell 1, the symmetry is provided with two installation inserted bars 24 in the mounting box 22, the installation jack has all been seted up to the lateral part of two fixed lugs 23, the one end that two installation inserted bars 24 kept away from each other all extends to the mounting box 22 outside and runs through two installation jacks respectively, install fixed sleeve 25 on the lateral part inner wall of mounting box 22, fixed sleeve 25 internal rotation cup joints control bull stick 26, it installs linkage gear 27 to cup joint on the control bull stick 26, the L-shaped rack 28 with linkage gear 27 engaged with is all installed to the one end that two installation inserted bars 24 are close to each other, install the elasticity gyration unit on the control bull stick 26, the one end of control bull stick 26 extends to maintenance board 2 outside and installs the locking control unit. The benefit that sets up like this is, when rotating control bull stick 26, can drive two installation inserted bars 24 through linkage gear 27, L shape rack 28 and move in opposite directions or back of the body mutually, has changed the position relation between installation inserted bar 24 and the installation jack, and then can fix or loosen mounting box 22 to realized can carrying out quick assembly disassembly's purpose to access panel 2, made things convenient for the staff to overhaul the maintenance.

In the present embodiment, the elastic rotation unit includes a torsion spring 29 disposed in the fixing sleeve 25 and sleeved on the control rotation rod 26, and both ends of the torsion spring 29 are respectively installed on the inner side wall of the fixing sleeve 25 and the outer peripheral side of the control rotation rod 26. The benefit that sets up like this is, when clockwise rotation control bull stick 26 drove two installation inserted bars 24 and removes in opposite directions, can make torsion spring 29 take place elastic deformation, when loosening control bull stick 26, under torsion spring 29's spring action, can make control bull stick 26 automatic reversal, and then can drive two installation inserted bars 24 and move back on the back and insert the installation jack internal fixation, convenient laborsaving back to back.

In this embodiment, the locking control unit includes a hexagonal connecting rod 30 installed at the end of the control rotating rod 26, a control knob 32 is slidably sleeved on the hexagonal connecting rod 30, an anti-falling block 31 is installed at the end of the hexagonal connecting rod 30, a plurality of locking insertion rods 33 are uniformly installed at the side of the control knob 32, a plurality of locking insertion holes 34 are uniformly opened at the outer side of the access panel 2, the end of the locking insertion rod 33 extends into the locking insertion hole 34, and an elastic reset element is installed on the control knob 32. The benefit that sets up like this, when pulling control knob 32, can drive locking inserted bar 33 and shift out outside locking jack 34, at this moment, control knob 32 is in the unclamping state, rotatable control knob 32 drives control bull stick 26 through hexagonal connecting rod 30 and rotates and carry out dismouting operation, when pushing control knob 32 and making locking inserted bar 33 insert in locking jack 34, control knob 32 can be fixed, effectively reduce the condition that appears leading to access panel 2 to take place to become flexible and drop because of touch control knob 32 carelessly, it is more reliable during the use.

In this embodiment, the elastic return element includes a return spring 35 sleeved on the hexagonal connection rod 30, and two ends of the return spring 35 are respectively attached to the anti-falling block 31 and the side portion of the control knob 32. The advantage of this arrangement is that when the control knob 32 is released, the control knob 32 is pushed by the elastic force of the return spring 35 to automatically return, so that the locking rod 33 is inserted into the locking hole 34 for automatic fixing, and the fixing state can be always maintained, stable and reliable.

The working principle of the invention is as follows:

when the biaxial stretching motor 7 is started, the connecting convex block 8 can drive the reciprocating screw rod 9 to rotate circumferentially, and then the reciprocating moving block 10 can drive the heat dissipation fan 11 to rotate circumferentially, and meanwhile, under the combined action of the planetary gear 12 and the fixed gear rack 13, the reciprocating screw rod 9 can rotate in the circumferential rotation process, and then the reciprocating moving block 10 can drive the heat dissipation fan 11 to move back and forth on the radius of the circumferential rotation, so that the purpose of uniformly blowing and dissipating heat of electronic components in the device is realized, the heat dissipation effect is good, the situation that the electronic components are burnt out due to overhigh temperature is effectively reduced, and the practicability is good.

In the operation process of the double-shaft extension motor 7, the drive rotating rod 15 can be driven to rotate, the drive rotating rod 15 can rotate through the connecting rotating arm 16, the movable sliding rod 17, the connecting plate 18 and the fastening bolt 21 drive the cleaning brush 19 to rotate circumferentially, automatic cleaning treatment is carried out on the dustproof net 6, and meanwhile, under the elastic action of the extrusion spring 20, the cleaning brush 19 can be pushed to be extruded to be tightly attached to the outer surface of the dustproof net 6 for cleaning treatment all the time, the cleaning effect is better, the situation that the dustproof net 6 is blocked by dust is effectively reduced, and the ventilation effect of the dustproof net 6 is ensured.

When pulling and rotating control knob 32, can drive control bull stick 26 through hexagonal connecting rod 30 and rotate, control bull stick 26 rotates and can pass through linkage gear 27, L shape rack 28 drives two installation inserted bars 24 and moves in opposite directions and dodges, when loosening control knob 32, under torque spring 29's spring action, can make control bull stick 26 automatic reversal, and then can drive two installation inserted bars 24 and move back to back in the back automatic installation inserted bar that inserts, it is fixed with mounting box 22, thereby realized can carrying out quick assembly disassembly's purpose to access panel 2, make things convenient for the staff to overhaul the maintenance.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still make modifications to the technical solutions described in the foregoing embodiments, or make equivalent substitutions and improvements to part of the technical features of the foregoing embodiments, and any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a three-phase is from net inverter overload protection device, includes device shell (1), access panel (2) and evenly dispels the heat the mechanism, its characterized in that: a circuit board is installed on the inner wall of the side part of the device shell (1), a control processor (3), a current detector (4) and a voltage detector (5) are fixedly arranged on the circuit board, a ventilation opening is formed in the side part of the maintenance board (2), and a dust screen (6) is installed in the ventilation opening;

the uniform heat dissipation mechanism comprises a double-shaft extension motor (7) arranged on the inner side part of the dust screen (6), one end of an output shaft of the double-shaft extension motor (7) is provided with a connecting lug (8), the side part of the connecting lug (8) is rotatably provided with a reciprocating lead screw (9), a reciprocating block (10) is sleeved on the reciprocating lead screw (9) in a threaded manner, the side part of the reciprocating block (10) is provided with a heat dissipation fan (11), the maintenance plate (2) is provided with a moving self-rotation unit used for enabling the reciprocating lead screw (9) to rotate, and the reciprocating block (10) is provided with a limited guide unit;

the other end of an output shaft of the double-shaft extension motor (7) is connected with an anti-blocking assembly used for cleaning the dust screen (6), and two convenient disassembly and assembly assemblies used for quickly fixing or loosening the access panel (2) are symmetrically installed on the device shell (1).

2. The three-phase off-grid inverter overload protection device according to claim 1, wherein: the movable autorotation unit comprises a planetary gear (12) arranged at the end part of the reciprocating screw rod (9), a plurality of straight rods are uniformly arranged at the inner side part of the maintenance plate (2), a plurality of fixed racks (13) are jointly arranged at one ends of the straight rods, and the planetary gear (12) is meshed with the fixed racks (13).

3. The three-phase off-grid inverter overload protection device of claim 1, wherein: the limiting guide unit comprises a limiting guide rod (14) arranged on the side of the connecting lug (8), and the end of the limiting guide rod (14) penetrates through the reciprocating block (10).

4. The three-phase off-grid inverter overload protection device of claim 1, wherein: prevent stifled subassembly including installing the biax is stretched drive bull stick (15) of motor (7) output shaft other end, the tip of drive bull stick (15) is run through dust screen (6) and is installed and connect rocking arm (16), two sliding holes have been seted up to the lateral part of connecting rocking arm (16), two equal slidable mounting has movable slide bar (17), two in the sliding hole connecting plate (18) are installed jointly to the one end of activity slide bar (17), install elasticity extrusion unit on connecting plate (18), be provided with cleaning brush (19) of laminating mutually on the outside portion of dust screen (6), cleaning brush (19) are installed through fastening unit on the lateral part of connecting plate (18).

5. The three-phase off-grid inverter overload protection device of claim 4, wherein: the elastic extrusion unit comprises an extrusion spring (20) sleeved on the movable sliding rod (17), and two ends of the extrusion spring (20) are respectively attached to the connecting rotating arm (16) and the side portion of the connecting plate (18).

6. The three-phase off-grid inverter overload protection device of claim 4, wherein: the fastening unit comprises a fastening bolt (21) arranged on the connecting plate (18), a bolt through hole is formed in the side portion of the connecting plate (18), a fastening screw hole is formed in the side portion of the cleaning brush (19), and one end of the fastening bolt (21) penetrates through the bolt through hole and is installed in the fastening screw hole in a threaded mode.

7. The three-phase off-grid inverter overload protection device of claim 1, wherein: convenient dismouting subassembly is including installing mounting box (22) on access panel (2) the inside portion, install on the inner wall of device shell (1) two with mounting box (22) assorted fixed lug (23), the symmetry is provided with two installation inserted bar (24), two in mounting box (22) the installation jack has all been seted up to the lateral part of fixed lug (23), two the one end of keeping away from each other of installation inserted bar (24) all extends to mounting box (22) is outer and run through two respectively the installation jack, install fixed sleeve (25) on the lateral part inner wall of mounting box (22), control bull stick (26) has been cup jointed in fixed sleeve (25) internal rotation, cup joint on control bull stick (26) and install linkage gear (27), two the one end that installation inserted bar (24) are close to each other all install with linkage gear (27) engaged with L shape rack (28), install elasticity gyration unit on control bull stick (26), the one end of control bull stick (26) extends to access panel (2) is outer and install locking control unit.

8. The three-phase off-grid inverter overload protection device according to claim 7, wherein: the elastic rotary unit comprises a torsion spring (29) which is arranged in the fixed sleeve (25) and sleeved on the control rotary rod (26), and two ends of the torsion spring (29) are respectively arranged on the inner side wall of the fixed sleeve (25) and the outer peripheral side of the control rotary rod (26).

9. The three-phase off-grid inverter overload protection device of claim 7, wherein: locking the control unit including installing hexagonal connecting rod (30) on control bull stick (26) tip, control knob (32) have been gone up to sliding sleeve on hexagonal connecting rod (30), anticreep piece (31) are installed to the tip of hexagonal connecting rod (30), a plurality of locking inserted bars (33) are evenly installed to the lateral part of control knob (32), a plurality of locking jacks (34) have evenly been seted up to the outside portion of access panel (2), the tip of locking inserted bar (33) extends to in the locking jack (34), install elasticity reset element on control knob (32).

10. The three-phase off-grid inverter overload protection device of claim 9, wherein: the elastic reset element comprises a reset spring (35) sleeved on the hexagonal connecting rod (30), and two ends of the reset spring (35) are respectively attached to the anti-falling block (31) and the side part of the control knob (32).