LU504923B1

LU504923B1 - Built-in energy storage device for wind turbine at low wind speed

Info

Publication number: LU504923B1
Application number: LU504923A
Authority: LU
Inventors: Chennuo Wang; Zhaoxin Niu; Zhankun Wang; Haibo Xu; Daqing Miao; Weili Zhang
Original assignee: Huaneng Liaoning Clean Energy Co Ltd
Priority date: 2023-02-21
Filing date: 2023-08-15
Publication date: 2024-02-15
Also published as: CN116146425A

Abstract

The present application relates to the technical field of wind power generation, and in particular to a built-in energy storage device for wind turbines at low wind speeds. The built-in energy storage device includes a nacelle. Blades are arranged on the outside of the nacelle. The blades are mounted on a main shaft. A generator is arranged inside the nacelle. An output end of the generator is connected with a speed-up gearbox. An end of the main shaft is connected with the speed-up gearbox. An energy storage box is arranged below the generator inside the nacelle. A temperature sensor is arranged on an inner wall of the energy storage box. A battery box is fixedly arranged inside the energy storage box. Two accumulators are arranged symmetrically in the battery box. The generator is electrically connected to the two accumulators through wires. The upper surface of the battery box is symmetrically provided with switching buttons. The surrounding temperature can be relatively constant when the accumulator is being charged and discharged, the influence of temperature can be reduced, and the service life of the battery can be prolonged.

Description

BUILT-IN ENERGY STORAGE DEVICE FOR WIND TURBINE AT LOW WIND

SPEED

FIELD

[0001] The present application relates to the technical field of wind power generation, and in particular to a built-in energy storage device for wind turbines at low wind speeds.

BACKGROUND

[0002] Wind power generation is the use of wind energy to generate electricity, and wind turbines are machines that convert wind energy into electrical energy. The wind wheel is the most important part of the wind turbine, consisting of blades and hubs. The blade has a good dynamic shape, and generates aerodynamic force under the airflow to drive the wind wheel to rotate, so as to convert the wind energy into mechanical energy. The gearbox then speeds up to drive the generator to convert the mechanical energy into electrical energy. Then, according to the specific requirements, the electrical energy is stored as chemical energy through appropriate conversion or supplied to the grid or directly supplied to the load.

[0003] For example, the patent application No. CN202211066281.1 proposes a housing assembly that includes a nacelle and a tower body. The nacelle is arranged on the top of the tower body. The tower body is connected to the ground. À transmission assembly 1s arranged inside the nacelle, including a primary transmission structure and a secondary transmission structure. The primary transmission structure is arranged on the upper part of the chamber of the nacelle, and extends to the outside of the nacelle to connect with the fan blades. The secondary transmission structure is arranged at the bottom of the chamber of the nacelle. The moving assembly is arranged inside the nacelle and the tower body, including the primary moving structure and the secondary moving structure. The primary moving structure is arranged between the primary transmission structure and the secondary transmission structure.

The secondary moving structure surrounds the primary moving structure and extends to the inside of the tower body.

[0004] According to the above patent application, when the wind speed is low, the stored mechanical energy can be converted into electrical energy through the gravitational potential energy, so as to improve the power generation effect at low wind speeds. However, when the battery stores the generated electric energy, the charging effect of the battery 1s prone to high or low temperature since its charging and discharging are sensitive to temperature, which reduces the service life of the battery.

SUMMARY

[0005] The purpose of the present application 1s to provide a built-in energy storage device for wind turbines at low wind speeds, so as to solve the problems raised in the above- mentioned BACKGROUND part.

[0006] In order to achieve the above purpose, the following technical solutions are provided according to the present application.

[0007] The built-in energy storage device for wind turbines at low wind speeds includes a nacelle. Blades are arranged on the outside of the nacelle. The blades are mounted on a main shaft. À generator is arranged inside the nacelle. An output end of the generator is connected with a speed-up gearbox. An end of the main shaft is connected with the speed-up gearbox.

An energy storage box is arranged below the generator inside the nacelle. A temperature sensor is arranged on an inner wall of the energy storage box. A battery box is fixedly arranged inside the energy storage box. Two accumulators are arranged symmetrically in the battery box. The generator is electrically connected to the two accumulators through wires.

The upper surface of the battery box is symmetrically provided with switching buttons. À switching assembly is arranged between the two switching buttons. The switching assembly is configured to press the switching button for the generator to charge the two accumulators sequentially. A connecting pipe communicates with the side wall of the energy storage box. A heating box is arranged on the connecting pipe. A thermostat air heater is arranged in the heating box. An end surface of the connecting pipe is connected with an outlet of a fan. An air guide opening is defined on a lower surface of the nacelle close to the blades. An inlet of the fan is connected with the air guide opening through a square pipe. A movable filter assembly is arranged inside the square pipe. The fan includes a rotating shaft inside the fan. A first bevel gear is fixedly arranged on the rotating shaft. The first bevel gear is connected with an execution end of a linkage assembly. The linkage assembly is configured to vibrate the filter assembly.

[0008] As a preferred solution of the present application, the filter assembly includes a filter screen. A length of the filter screen is less than a width of the inner wall of the square pipe.

Outer walls of both sides of the filter screen are integrally provided with baffles. Sides of the two baffles away from the filter screen are respectively integrally provided with an edge plate and a movable plate. Both the edge plate and the movable plate pass through the square pipe and extend to the outside. Multiple springs are arranged on both sides of the upper and lower sides of the edge plate. Both ends of the multiple springs are respectively fixed to the baffle plate and the inner wall of the square pipe. The end surface of the movable plate 1s arc-shaped.

[0009] As a preferred solution of the present application, the linkage assembly includes a connecting shaft transversely passing through the side wall of the fan. Both ends of the connecting shaft are fixedly arranged with second bevel gears. One of the second bevel gears is engaged with the first bevel gear, and the other second bevel gear is engaged with a third bevel gear. The third bevel gear fixedly surrounds a rotating rod. Both ends of the rotating rod are respectively connected in rotation with the bottom of the heating box and the inner bottom wall of the energy storage box. A protrusion fixedly surrounds the rotating rod below the third bevel gear.

[0010] As a preferred solution of the present application, the protrusion is at the same level as the filter assembly. The protruding end of the protrusion matches with a movable plate arranged in the filter assembly.

[0011] As a preferred solution of the present application, the side of the nacelle away from the blade and the side of the energy storage box away from the heating box each are provided with multiple communicating vent holes. The energy storage box is provided with a movable shielding assembly at the inner wall of the vent hole. The shielding assembly includes a shielding plate. A rubber layer is bonded to an end surface of the shielding plate. The side of the rubber layer away from the shielding plate is in contact with the inner wall of the energy storage box.

[0012] As a preferred solution of the present application, a welding plate is provided in the center of the shielding plate near the battery box. An L-shaped rob is welded on the welding plate. The other end of the L-shaped rod surrounds a screw rod. One end of the screw rod is fixedly connected with an electric motor. The other end of the screw rod is movably connected with the inner wall of the energy storage box. The electric motor is fixed on a mounting plate by bolts. The bottom of the mounting plate is fixedly connected with the inner bottom wall of the energy storage box. The upper surface of the mounting plate located below the shielding plate is integrally provided with a slide rail. The lower surface of the shielding plate 1s provided with a slide slot matched with the slide rail.

[0013] As a preferred solution in the present application, the multiple vent holes are all right- angled trapezoids in cross-section.

[0014] As a preferred solution of the present application, the switching assembly includes a support frame fixed on the upper surface of the battery box. A movable slot is defined on the top of the support frame. À horizontal plate is movably connected to the movable slot through a shaft. Pressure heads are fixedly connected to the bottoms of both ends of the horizontal plate. Both of the pressure heads are matched with the switching buttons. The inner top wall of the energy storage box is fixed with electric telescopic rods symmetrically. The two electric telescopic rods are all located above the two ends of the horizontal plate. Both telescopic ends of the two electric telescopic rods are fixed with pressure plates.

[0015] As a preferred solution of the present application, the horizontal plate is arranged obliquely. The lower surfaces of the two pressure plates are embedded with balls.

[0016] As a preferred solution of the present application, the two accumulators are electrically connected to an electrical element in the energy storage box through wires.

[0017] Compared with the prior art, the beneficial effects of the present application are as follows. In view of the problems raised by the BACKGROUND part, the temperature sensor monitors the temperature inside the energy storage box in the present application. When the temperature is higher than a preset value, the fan works. The fan sends the external air into the energy storage box through the air guide opening, the square pipe and the connecting pipe.

The air in the energy storage box flows and is discharged from the vent holes to achieve cooling. When the temperature is lower than the preset value, the thermostatic air heater works to heat the incoming air. The heated air enters the energy storage box. In this case, the shielding assembly blocks the vent holes to prevent the temperature from dropping, so as to increase the temperature in the energy storage box. Therefore, the surrounding temperature can be relatively constant when the accumulator is being charged and discharged, the influence of temperature can be reduced, and the service life of the battery can be prolonged.

In addition, when the fan rotates, the suctioned air is filtered for dust and the dust is vibrated to prevent dust from clogging filter holes.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG. 1 is a perspective view of an overall structure of a built-in energy storage device according to the present application;

[0019] FIG. 2 is a diagram of an overall side view sectional structure of the built-in energy storage device according to the present application; 5 [0020] FIG. 3 is an enlarged view at A of the built-in energy storage device according to the present application;

[0021] FIG. 4 is a schematic diagram of a switching assembly according to the present application;

[0022] FIG. 5 is a front view diagram of a sectional structure a nacelle according to the present application; and

[0023] FIG.6 is a schematic diagram of a square pipe.

[0024] In the drawings: 1, nacelle; 101, blade; 102, main shaft; 103, speed-up gearbox; 104, generator; 105, air guide opening; 2, energy storage box; 201, battery box; 2011, accumulator; 2012, switching button; 202, connecting pipe; 203, temperature sensor; 204, heating box; 2041, thermostatic air heater, 205, fan; 2051, rotating shaft; 2052, first bevel gear; 3, switching assembly; 301, support frame; 3011, movable slot; 302, horizontal plate; 303, pressure head; 304, electric telescopic rod; 305, pressure plate; 4, square pipe; 5, filter assembly; 501, filter screen; 502, baffle plate; 503, edge plate; 504, spring; 505, arc surface; 506, movable plate; 6, linkage assembly; 601, connecting shaft; 602, second bevel gear; 603, rotating rod; 604, third bevel gear; 605, protrusion; 7, vent hole; 8, shielding assembly; 801, mounting plate; 8011, slide rail; 802, shielding plate; 8021, rubber layer; 8022, slide slot; 8023, welding plate; 803, electric motor; 804, screw rod; and 805, L-shaped rod.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The technical solutions in the embodiments of the present application are clearly and completely described below in conjunction with the embodiments of the present application.

Apparently, the described embodiments are only some rather than all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of the present application.

[0026] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the drawings. Several examples of the present application are given. However, the present application may be embodied in many different forms and is not limited to the embodiments described herein.

Instead, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0027] It should be noted that when an element is referred to as being "fixed on" another element, it may be directly on the other element or there may be an intervening element.

When an element is referred to as being "connected to" another element, it may be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and similar expressions are used herein for purposes of illustration only.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present application belongs. The terms used herein in the specification of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

[0029] Referring to FIGS 1 to 6, the following technical solutions are provided according to the present application.

[0030] A built-in energy storage device for wind turbines at low wind speeds includes a nacelle 1. Blades 101 are arranged on the outside of the nacelle 1. The blades 101 are mounted on a main shaft 102. À generator 104 is arranged inside the nacelle 1. An output end of the generator 104 is connected with a speed-up gearbox 103. An end of the main shaft 102 is connected with the speed-up gearbox 103. An energy storage box 2 is arranged below the generator 104 inside the nacelle 1. A temperature sensor 203 is arranged on an inner wall of the energy storage box 2. A battery box 201 is fixedly arranged inside the energy storage box 2. Two accumulators 2011 are arranged symmetrically in the battery box 201. The generator 104 is electrically connected to the two accumulators 2011 through wires. The upper surface of the battery box 201 is symmetrically provided with switching buttons 2012. A switching assembly 3 is arranged between the two switching buttons 2012. The switching assembly 3 is configured to press the switching button 2012 for the generator 104 to charge the two accumulators 2011 sequentially. A connecting pipe 202 communicates with the side wall of the energy storage box 2. A heating box 204 is arranged on the connecting pipe 202. A thermostat air heater 2041 is arranged in the heating box 204. An end surface of the connecting pipe 202 is connected with an outlet of a fan 205. An air guide opening 105 is defined on a lower surface of the nacelle 1 close to the blades 101. An inlet of the fan 205 1s connected with the air guide opening 105 through a square pipe 4. A movable filter assembly 5 1s arranged inside the square pipe 4. The fan 205 includes a rotating shaft 2051 inside the fan 205. A first bevel gear 2052 is fixedly arranged on the rotating shaft 2051. The first bevel gear 2052 is connected with an execution end of a linkage assembly 6. The linkage assembly 6 is configured to vibrate the filter assembly 5. The side of the nacelle 1 away from the blade 101 and the side of the energy storage box 2 away from the heating box 204 each are provided with multiple communicating vent holes 7. The multiple vent holes 7 are all right-angled trapezoids in cross-section, which can reduce the entry of rainwater in rainy days. The energy storage box 2 is provided with a movable shielding assembly 8 on the inner wall of the vent hole 7. The two accumulators 2011 are electrically connected to an electrical element in the energy storage box 2 through wires.

[0031] The blade 101 drives the main shaft 102 to rotate when rotating at a low wind speed.

The main shaft 102 drives the generator 104 to work through the speed-up gearbox 103 to convert mechanical energy into electrical energy. The generated electrical energy is stored in the accumulator 2011 through wires. When one accumulator 2011 is full, the switching button 2012 is pressed through the switching assembly 3 to switch to another accumulator 2011 for charging the accumulator 2011. The state detection of the accumulator 2011 adopts the prior art, which is not described in detail here. When the accumulator 2011 is being charged and discharged, the temperature sensor 203 whose model is ATE100 detects the temperature inside the energy storage box 2 and the ambient temperature of the accumulator 2011. When the detected temperature is higher than a preset value (15 to 30 degrees), the fan 205 works.

The fan 205 sends external air into the energy storage box 2 through the air guide opening 105, the square pipe 4 and the connecting pipe 202. The air in the energy storage box 202 flows and is discharged from the vent holes 7 to realize cooling. When the detected temperature is lower than the preset value (15 to 30 degrees), the thermostatic air heater 2041 works to heat up the incoming air. The heated air enters the energy storage box 2. The shielding assembly 8 shields the vent holes 7 to prevent the temperature from dropping, so as to ensure that the temperature in the energy storage box 2 rises. Therefore, when the accumulator 2011 is being charged and discharged, the ambient temperature is relatively constant, which reduces the influence of temperature and prolongs the service life of the accumulator 2011. In addition, the dust 1s filtered out through the filter assembly 5 when the air enters, so as to reduce the possibility of dust accumulation inside the energy storage box 2.

Further, when the fan 205 rotates, the linkage assembly 6 vibrates the filter assembly 5 to prevent dust from clogging the filter holes.

[0032] In some embodiments, referring to FIG. 2, FIG. 3 and FIG. 6, the filter assembly 5 includes a filter screen 501. The length of the filter screen 501 is smaller than the width of the inner wall of the square pipe 4. Both sides of the filter screen 501 are integrally provided with baffles 502. The sides of the two baffles 502 away from the filter screen 501 are respectively integrally provided with an edge plate 503 and a movable plate 506. Both the edge plate 503 and the movable plate 506 pass through the square pipe 4 and extend to the outside. Multiple springs 504 are provided along the upper and lower sides of the edge plate 503. Both ends of the multiple springs 504 are fixedly connected to the baffle plate 502 and the inner wall of the square pipe 4 respectively. The end surface of the movable plate 506 is an arc surface 505.

The linkage assembly 6 includes a connecting shaft 601 transversely passing through the side wall of the fan 205. Both ends of the connecting shaft 601 are fixedly arranged with second bevel gears 602. One second bevel gear 602 is engaged with the first bevel gear 2052. The other second bevel gear 602 is engaged with a third bevel gear 604. The third bevel gear 604 fixedly surrounds the rotating rod 603. Two ends of the rotating rod 603 are respectively connected in rotation with the bottom of the heating box 204 and the inner bottom wall of the energy storage box 2. A protrusion 605 fixedly surrounds the rotating rod 603 below the third bevel gear 604. The protrusion 605 is on the same level as the filter assembly 5. The protruding end of the protrusion 605 matches with the movable plate 506 provided in the filter assembly 5.

[0033] When the fan 205 works to draw in external air, the external air passes through the filter assembly 5 provided inside the square pipe 4. The filter screen 501 filters out the dust contained in the passing air. In addition, when the fan 205 is working, the internal rotating shaft 2051 drives the first bevel gear 2052 to rotate. The rotating first bevel gear 2052 drives the second bevel gear 602 in the linkage assembly 6 to rotate. The second bevel gear 602 drives the connecting shaft 601 to rotate. The rotating connecting shaft 601 drives the other second bevel gear 602 to rotate, so as to drive the third bevel gear 604 meshed with the second bevel gear 602 to rotate. The third bevel gear 604 drives the rotating rod 603 to rotate.

The rotating rod 603 drives the protrusion 605 to rotate. When the protruding end of the protrusion 605 rotates to one side of the movable plate 506, the movable plate 506 1s pushed to move. The moving movable plate 506 drives the filter screen 501 to move through the baffle plate 502. The filter screen 501 is driven by the baffle plate 502 to move along the edge plate 503 and press the multiple springs 504. When the protruding end of the protrusion 605 is no longer in contact with the movable plate 506, the filter screen 501 and the baffle plate 502 are reset under the elastic action of the multiple springs 504. In this way, the filter screen 501 vibrates, thereby preventing dust from clogging the filter holes.

[0034] In some embodiments, referring to FIG. 2 and FIG. 5, the shielding assembly 8 includes a shielding plate 802. A rubber layer 8021 is bonded to the end surface of the shielding plate 802. The side of the rubber layer 8021 away from the shielding plate 802 is in contact with the inner wall of the energy storage box 2. A welding plate 8023 is provided in the center of the shielding plate 802 near the battery box 201. An L-shaped rob 805 is welded on the welding plate 8023. The other end of the L-shaped rod 805 is wound on the screw rod 804. One end of the screw rod 804 is fixedly connected with an electric motor 803. The other end of the screw rod 804 is movably connected with the inner wall of the energy storage box 2. The electric motor 803 is fixed on the mounting plate 801 by bolts. The bottom of the mounting plate 801 is fixedly connected with the inner bottom wall of the energy storage box 2. The upper surface of the mounting plate 801 is located below the shielding plate 802 and is integrally provided with a slide rail 8011. A slide slot 8022 matched with the slide rail 8011 is defined on the lower surface of the shielding plate 802. The slide rail 8011 and the slide slot 8022 restrict the shielding plate 802.

[0035] When the shield assembly 8 works, the electric motor 803 works to drive the screw rod 804 to rotate. The rotating screw 804 drives the L-shaped rod 805 to drive the shielding plate 802 to move laterally through the welding plate 8023. Therefore, the slide slot 8022 of the shielding plate 802 slides along the slide rail 8011, and the moving shielding plate 802 shields or exposes the multiple vent holes 7 via the rubber layer 8021.

[0036] In some embodiments, referring to FIG. 2 and FIG. 4, the switching assembly 3 includes a support frame 301 fixed to the upper surface of the battery box 201. The top of the support frame 301 is provided with a movable slot 3011. A horizontal plate 302 is movably connected to the movable slot 3011 through a shaft. Pressure heads 303 are fixedly connected to the bottoms of both ends of the horizontal plate 302. Both pressure heads 303 match with the switching button 2012. The inner top wall of the energy storage box 2 is symmetrically fixed with electric telescopic rods 304. The two electric telescopic rods 304 are located above the two ends of the horizontal plate 302. Both telescopic ends of the two electric telescopic rods 304 are fixed with a pressure plate 305. The horizontal plate 302 is arranged obliquely.

The lower surfaces of the two pressure plates 305 each are embedded with balls.

[0037] When charging the accumulator 2011 alternately, the two electric telescopic rods 304 work alternately. The telescopic end of the originally working electric telescopic rod 304 is retracted. The retracted telescopic end cancels the pressing of the end of the horizontal plate 302. The telescopic end of the electric telescopic rod 304 that was not working originally is expanded, and the expanded telescopic end presses the other end of the horizontal plate 302.

The horizontal board 302 is like a balance board, and the side under force moves downwards and drives the pressure head 303 to press the switching button 2012 below. Therefore, the accumulator 2011 communicates with the circuit connected to the generator 104 to switch accumulators 2011.

[0038] The workflow of this application is as follows. When in use, the blade 101 rotates to drive the main shaft 102 to rotate at low wind speeds. The main shaft 102 drives the generator 104 to work via the speed-up gearbox 103 to convert mechanical energy into electrical energy.

The generated electric energy is then stored in the accumulator 2011 through wires. When one accumulator 2011 is full, the two electric telescopic rods 304 in the switch assembly 3 work alternately. The telescopic end of the originally working electric telescopic rod 304 is retracted. The retracted telescopic end cancels the pressing of the end of the horizontal plate 302. The telescopic end of the electric telescopic rod 304 that was not working originally is expanded, and the expanded telescopic end presses the other end of the horizontal plate 302.

The horizontal board 302 is like a balance board, and the side under force moves downwards and drives the pressure head 303 to press the switching button 2012 below. Therefore, the accumulator 2011 communicates with the circuit connected to the generator 104 to switch accumulators 2011. When the accumulator 2011 is being charged and discharged, the temperature sensor 203 detects the temperature inside the energy storage box 2 and the ambient temperature of the accumulator 2011. When the detected temperature is higher than the preset value (15 to 30 degrees), the fan 205 works. The fan 205 sends external air into the energy storage box 2 through the air guide opening 105, the square pipe 4 and the connecting pipe 202. The external air passes through the filter assembly 5 provided inside the square pipe

4. The filter screen 501 filters out the dust contained in the air. In addition, when the fan 205 is working, the internal rotating shaft 2051 drives the first bevel gear 2052 to rotate. The rotating first bevel gear 2052 drives the second bevel gear 602 in the linkage assembly 6 to rotate. The second bevel gear 602 drives the connecting shaft 601 to rotate. The rotating connecting shaft 601 drives the other second bevel gear 602 to rotate, so as to drive the third bevel gear 604 meshed with the second bevel gear 602 to rotate. The third bevel gear 604 drives the rotating rod 603 to rotate. The rotating rod 603 drives the protrusion 605 to rotate.

When the protruding end of the protrusion 605 rotates to one side of the movable plate 506, the movable plate 506 is pushed to move. The moving movable plate 506 drives the filter screen 501 to move through the baffle plate 502. The filter screen 501 is driven by the baffle plate 502 to move along the edge plate 503 and press the multiple springs 504. When the protruding end of the protrusion 605 is no longer in contact with the movable plate 506, the filter screen 501 and the baffle plate 502 are reset under the elastic action of the multiple springs 504. In this way, the filter screen 501 vibrates, thereby preventing dust from clogging the filter holes. The air flowing into the energy storage box 202 drives air inside the energy storage box 202 to flow and is discharged from the vent holes 7 to realize cooling. When the detected temperature is lower than the preset value (15 to 30 degrees), the thermostatic air heater 2041 works to heat up the incoming air. The heated air enters the energy storage box 2.

The shield assembly 8 works, and the electric motor 803 works to drive the screw rod 804 to rotate. The rotating screw 804 drives the L-shaped rod 805 to drive the shielding plate 802 to move laterally through the welding plate 8023. Therefore, the slide slot 8022 of the shielding plate 802 slides along the slide rail 8011, and the moving shielding plate 802 shields the multiple vent holes 7 via the rubber layer 8021 to prevent the temperature from dropping, so as to ensure that the temperature in the energy storage box 2 rises. Therefore, when the accumulator 2011 is being charged and discharged, the ambient temperature is relatively constant.

[0039] The embodiments of the present application have been shown and described. However, it should be understood that those skilled in the art may make various changes, modifications, substitutions and variations to these embodiments without departing from the principle and spirit of the present application. The scope of the present application is defined by the claims appended hereto and their equivalents.

Claims

1. À built-in energy storage device for wind turbines at low wind speeds, comprising: a nacelle (1), wherein blades (101) are arranged outside the nacelle (1), the blades (101) are mounted on a main shaft (102), a generator (104) is arranged inside the nacelle (1), an output end of the generator (104) is connected with a speed-up gearbox (103), an end of the main shaft (102) is connected with the speed-up gearbox (103), an energy storage box (2) is arranged below the generator (104) inside the nacelle (1), a temperature sensor (203) is arranged on an inner wall of the energy storage box (2), a battery box (201) is fixedly arranged inside the energy storage box (2), two accumulators (2011) are arranged symmetrically in the battery box (201), the generator (104) is electrically connected to the two accumulators (2011) through wires, an upper surface of the battery box (201) is symmetrically provided with switching buttons (2012), a switching assembly (3) is arranged between the two switching buttons (2012), the switching assembly (3) is configured to press the switching button (2012) for the generator (104) to charge the two accumulators (2011) sequentially, a connecting pipe (202) is in communication with the side wall of the energy storage box (2), a heating box (204) is arranged on the connecting pipe (202), a thermostat air heater (2041) is arranged in the heating box (204), an end surface of the connecting pipe (202) is connected with an outlet of a fan (205), an air guide opening (105) is defined on a lower surface of the nacelle (1) close to the blades (101), an inlet of the fan (205) is connected with the air guide opening (105) through a square pipe (4), a movable filter assembly (5) is arranged inside the square pipe (4), the fan (205) comprises a rotating shaft (2051) inside the fan (205), a first bevel gear (2052) is fixedly arranged on the rotating shaft (2051), the first bevel gear (2052) is connected with an execution end of a linkage assembly (6), and the linkage assembly (6) is configured to vibrate the filter assembly (5).

2. The built-in energy storage device for wind turbines at low wind speeds according to claim 1, wherein the filter assembly (5) comprises a filter screen (501), a length of the filter screen (501) is less than a width of an inner wall of the square pipe (4), outer walls of both sides of the filter screen (501) are integrally provided with baffles (502), sides of the two baffles (502) away from the filter screen (501) are respectively integrally provided with an edge plate (503)

and a movable plate (506), both the edge plate (503) and the movable plate (506) pass through the square pipe (4) and extend to outside, a plurality of springs (504) are arranged on both sides of the upper and lower sides of the edge plate (503), both ends of the plurality of springs (504) are respectively fixed to the baffle plate (502) and the inner wall of the square pipe (4), and an end surface of the movable plate (506) is arc-shaped.

3. The built-in energy storage device for wind turbines at low wind speeds according to claim 1, wherein the linkage assembly (6) comprises a connecting shaft (601) transversely passing through a side wall of the fan (205), both ends of the connecting shaft (601) are fixedly arranged with second bevel gears (602), one of the second bevel gears (602) is engaged with the first bevel gear (2052), and the other of the second bevel gears (602) 1s engaged with a third bevel gear (604), the third bevel gear (604) fixedly surrounds a rotating rod (603), both ends of the rotating rod (603) are respectively connected in rotation with a bottom of the heating box (204) and an inner bottom wall of the energy storage box (2), and a protrusion (605) fixedly surrounds the rotating rod (603) below the third bevel gear (604).

4. The built-in energy storage device for wind turbines at low wind speeds according to claim 3, wherein the protrusion (605) is at the same level as the filter assembly (5), and a protruding end of the protrusion (605) matches with a movable plate (506) arranged in the filter assembly (5).

5. The built-in energy storage device for wind turbines at low wind speeds according to claim 1, wherein a side of the nacelle (1) away from the blade (101) and the side of the energy storage box (2) away from the heating box (204) each are provided with a plurality of communicating vent holes (7), the energy storage box (2) is provided with a movable shielding assembly (8) at an inner wall of the vent hole (7), the shielding assembly (8) comprises a shielding plate (802), a rubber layer (8021) is bonded to an end surface of the shielding plate (802), and a side of the rubber layer (8021) away from the shielding plate (802) is in contact with the inner wall of the energy storage box (2).

6. The built-in energy storage device for wind turbines at low wind speeds according to claim 5, wherein a welding plate (8023) is provided in a center of the shielding plate (802) near the battery box (201), an L-shaped rob (805) 1s welded on the welding plate (8023), the other end of the L-shaped rod (805) surrounds a screw rod (804), one end of the screw rod (804) is fixedly connected with an electric motor (803), the other end of the screw rod (804) is movably connected with the inner wall of the energy storage box (802), the electric motor (803) is fixed on a mounting plate (801) by bolts, a bottom of the mounting plate (801) is fixedly connected with an inner bottom wall of the energy storage box (2), an upper surface of the mounting plate (801) located below the shielding plate (802) is integrally provided with a slide rail (8011), a lower surface of the shielding plate (802) is provided with a slide slot (8022) matched with the slide rail (8011).

7. The built-in energy storage device for wind turbines at low wind speeds according to claim 5, wherein the plurality of vent holes (7) are all right-angled trapezoids in cross-section.

8. The built-in energy storage device for wind turbines at low wind speeds according to claim 1, wherein the switching assembly (3) comprises a support frame (301) fixed on the upper surface of the battery box (201), a movable slot (3011) is defined on top of the support frame (301), a horizontal plate (302) is movably connected to the movable slot (301) through a shaft, pressure heads (303) are fixedly connected to bottoms of both ends of the horizontal plate (302), both of the pressure heads (303) are matched with the switching buttons (2012), an inner top wall of the energy storage box (2) is fixed with electric telescopic rods (304) symmetrically, the two electric telescopic rods (304) are all located above two ends of the horizontal plate (302), and both telescopic ends of the two electric telescopic rods (304) are fixed with pressure plates (305).

9. The built-in energy storage device for wind turbines at low wind speeds according to claim 8, wherein the horizontal plate (302) is arranged obliquely, and lower surfaces of the two pressure plates (305) are embedded with balls.

10. The built-in energy storage device for wind turbines at low wind speeds according to claim 1, wherein the two accumulators (2011) are electrically connected to an electrical element in the energy storage box (2) through wires.