Energy storage type smooth generator power fluctuation device

Abstract

The invention relates to the technical field of renewable energy power generation system management, and discloses an energy storage type smooth generator power fluctuation device which comprises a planetary gear set, a cylinder connected with the planetary gear set, a rope wound on the cylinder and an energy storage structure connected with one end of the rope. The planetary gear set comprises a planetary carrier, a planetary pinion, a sun gear and a gear ring; each rope is composed of a winding section, a separating section and a connecting section which are sequentially connected from the starting end to the tail end. The starting end of the rope is fixedly connected to the end, connected with the planetary gear set, of the cylinder or the gear ring. The winding sections are synchronously wound on the outer side of the barrel side by side; the separation sections are tangent to the cylinder body and are distributed at equal intervals in the circumferential direction of the cylinder body. A planetary gear set, a barrel, a rope and an energy storage structure are arranged; the fluctuation part of the work originally borne by the generator is mostly converted into gravitational potential energy to be stored or released.

Description

Technical Field

[0001] The present invention relates to the technical field of renewable energy power generation system management, and particularly to a device for storing energy to smooth the power fluctuation of a generator. Background Art

[0002] The widely applied renewable energy power generations include wind power generation and hydroelectric power generation, and most other types of renewable energy power generation types are mostly restricted greatly; however, wind power generation is significantly affected by the randomness of wind speed, turbulence intensity and terrain; although the water energy is generally relatively stable, short-term fluctuations will also be generated due to turbulence; these fluctuations will cause power fluctuations in the corresponding power generation equipment during operation, and the work generated by the suddenly increased or decreased power is basically borne by the generator, thereby having various impacts on the power generation equipment, power generation efficiency, effect, etc. For example, in wind power generation, the sudden change in power will cause the fluctuation of the impeller speed, resulting in additional mechanical stress on components such as the gearbox and bearings, shortening the equipment life; reducing the unit efficiency, disturbing the electromagnetic balance of the generator, and affecting the power quality; large-scale power fluctuations may cause grid frequency deviation and voltage flicker, threatening the system stability; the variable-speed unit needs to frequently adjust the pitch angle or slip ratio to maintain power stability, increasing the complexity and energy consumption of the control system. The suddenly increased power will exceed the maximum rated upper limit of the motor and damage the motor.

[0003] In the prior art, most of these situations are dealt with by methods of suppressing fluctuations or reducing impacts, or by multi-dimensional technology collaboration to reduce the negative impacts of power fluctuations on the generator and the power grid. However, no consideration has been given to how to utilize the energy wasted when the power generation equipment is unable to convert it into electrical energy during power fluctuations. Therefore, a device that stores the peak work of the fluctuations and releases it during the low valley is needed. Summary of the Invention

[0004] The object of the present invention is to overcome the deficiencies existing in the prior art and provide a device for storing energy to smooth the power fluctuation of a generator. By setting a planetary gear set, a cylinder, a rope and an energy storage structure, most of the fluctuating work originally borne by the generator is converted into gravitational potential energy for storage and release; it can also reduce the maximum rated power required by the motor.

[0005] To achieve the above object, the present invention adopts the following technical solutions: A device for storing energy to smooth the power fluctuation of a generator, comprising a planetary gear set, a cylinder connected to the planetary gear set, a rope wound around the cylinder, and an energy storage structure connected to one end of the rope; The planetary gear set includes a planet carrier, a planet pinion, a sun gear and a ring gear; There are at least two ropes. From the starting end to the ending end, the rope consists of a winding section, a separating section, and a connecting section that are connected in sequence. The starting end of the rope is fixedly connected to one end where the cylinder is connected to the planetary gear set or the ring gear. The winding sections are wound side by side and synchronously on the outer side of the cylinder. The separating sections are tangent to the cylinder, and all the separating sections are equidistantly distributed along the circumferential direction of the cylinder.

[0006] Further, starting from the end connected to the separating section, the connecting section bypasses a fixed pulley and then is fixedly connected to the energy storage structure.

[0007] Further, a limiting card slot is arranged in a spiral shape on the outside of the cylinder, and the rope is located in the limiting card slot.

[0008] Further, the energy storage structure is a gravity energy storage structure or an elastic energy storage structure.

[0009] Further, the gravity energy storage structure includes a heavy object connected to the separating section, and an upper elastic limiter and a lower elastic limiter that are respectively arranged at intervals above and below the heavy object.

[0010] Further, the cylinder and the ring gear are integrally arranged or detachably and fixedly connected.

[0011] Further, the cylinder at least includes a small torque constant section, a continuously variable torque section, and a large torque constant section that are connected in sequence.

[0012] Further, bearings are arranged outside or inside the ring gear.

[0013] Further, when there are two ropes, they include a first rope and a second rope. The separating sections of the first rope and the second rope are symmetrically arranged outside the cylinder. The fixed pulleys include a first fixed pulley and a second fixed pulley. The heavy objects include a first heavy object connected to the first rope and a second heavy object connected to the second rope.

[0014] For the energy storage type smooth generator power fluctuation device, a bevel gear differential is used to replace the planetary gear set.

[0015] The beneficial effects of the present invention are as follows: By setting a planetary gear set, a cylinder, a rope, and an energy storage structure; the rope is wound on the cylinder. When the power fluctuates, the ring gear will rotate, and the cylinder rotates with the ring gear to make the rope move, converting the work originally borne by the generator into gravitational potential energy for storage; different diameter sections are set on the cylinder, corresponding to different torques; there are a large torque constant section, a continuously variable torque section, and a small torque constant section, and multiple sections with different torques can be further added according to the control accuracy requirements. In the large torque constant section, it corresponds to the maximum rated power of the generator, and in the small torque constant section, it corresponds to the minimum starting power of the generator. For a motor, a certain power corresponds to a certain torque and rotational speed.

[0016] It can reduce the maximum rated power required by the motor. For example, under the same working conditions and for the same wind power blade device, a traditional generator with a rated power of 10 KW only needs a generator with a power of 9 KW when equipped with a device for smoothing the power fluctuation of the generator. Or, a 10 KW generator can be paired with a wind power blade device with a higher wind speed and greater power, thus improving the overall power generation. Brief Description of the Drawings

[0017] Figure 1 It is a three-dimensional structure schematic diagram of a planetary gear set; Figure 2 It is a planar structure schematic diagram of a planetary gear set; Figure 3 It is a schematic diagram of the relationship between the ring gear and the rope in a side view structure; Figure 4 It is a schematic diagram of the overall structure.

[0018] In the figure: 1, bearing; 2, cylinder; 301, first rope; 302, second rope; 401, first fixed pulley; 402, second fixed pulley; 501, first heavy object; 502, second heavy object; 601, upper elastic limiter; 602, lower elastic limiter; 7, limit card slot; 8, planet carrier; 9, planet pinion; 10, sun gear; 11, ring gear. Detailed Embodiments

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present invention.

[0020] The directional terms mentioned in the present invention, such as "up", "down", "front", "back", "left", "right", "inside", "outside", "side", "top" and "bottom", etc., are only with reference to the orientation of the accompanying drawings. The directional terms used are for explaining and understanding the present invention, rather than for limiting the present invention.

[0021] Embodiment 1: As Figures 1-4 shown, an energy storage type device for smoothing the power fluctuation of a generator includes a planetary gear set, a cylinder 2 connected to the planetary gear set, a rope wound around the cylinder 2, and an energy storage structure connected to one end of the rope; The planetary gear set includes a planet carrier 8, planet pinions 9, a sun gear 10 and a ring gear 11; There are at least two ropes, and each rope consists of a winding section, a separating section, and a connecting section that are integrally connected in sequence from the starting end to the ending end; the winding section includes the starting end of the rope, and the connecting section includes the ending end of the rope; the starting ends of all the ropes are fixedly connected to one end of the cylinder 2 connected to the planetary gear set or the ring gear 11; all the winding sections start from their starting ends and are wound side by side and synchronously on the outer side of the cylinder 2; all the separating sections are tangent to the cylinder 2, and all the separating sections are equidistantly distributed along the circumferential direction of the cylinder 2.

[0022] After all the connecting sections start from the end connected to the separating section and bypass the fixed pulley, they are fixedly connected to the energy storage structure.

[0023] A limiting card slot 7 is arranged in a spiral shape outside the cylinder 2, and all the ropes are located in the limiting card slot 7, and the limiting card slot 7 is used to limit the positions of the ropes.

[0024] The energy storage structure is a gravity energy storage structure or an elastic energy storage structure; the gravity energy storage structure uses the energy converted from the stored gravitational potential energy, and the elastic energy storage structure uses the energy converted from the stored elastic potential energy; the spring potential energy is not as cost-effective as the gravitational potential energy, and the spring potential energy can be used to replace the gravitational potential energy at low power.

[0025] The gravity energy storage structure includes heavy objects connected to the separating section, and an upper elastic limiter 601 and a lower elastic limiter 602 that are respectively arranged at intervals above and below all the heavy objects; the elastic energy storage structure includes a spring with a fixed bottom and a top connected to the connecting section.

[0026] The cylinder 2 is integrally provided with or detachably and fixedly connected to the ring gear 11.

[0027] The cylinder 2 at least includes a small torque constant section, a continuously variable torque section, and a large torque constant section that are connected in sequence; the small torque constant section has the smallest diameter, the large torque constant section has the largest diameter, and the generatrix of the continuously variable torque section has at least one slope, and the curve slope can be correspondingly set according to the generator torque curve; if there is more than one slope, they are smoothly connected in sequence.

[0028] A bearing 1 is arranged outside or inside the ring gear 11 to limit the fixed-axis rotation of the ring gear 11.

[0029] When there are two ropes, they include a first rope 301 and a second rope 302; the separating sections of the first rope 301 and the second rope 302 are symmetrically arranged outside the cylinder 2; the fixed pulley includes a first fixed pulley 401 bypassed by the first rope 301 and a second fixed pulley 402 bypassed by the second rope 302; the fixed pulley is also used to ensure the direction and position distribution of the separating section; the heavy objects include a first heavy object 501 connected to the first rope 301 and a second heavy object 502 connected to the second rope 302.

[0030] Taking one of the methods as an example, the rotational power is input to the planet carrier 8. Through the combined action of the planet pinions 9 and the ring gear 11, the power is output to the sun gear 10, and the sun gear 10 drives the generator.

[0031] When the input power and the output power are balanced, it rotates uniformly. The planet pinion 9 rotates at a constant speed by itself, the planet carrier 8 rotates at a constant speed, and the ring gear 11 does not move. The torque exerted by the ring gear 11 on a single planet pinion 9 is equal to the torque exerted by the sun gear 10 on this single planet pinion 9. When the balance state is suddenly broken, that is, when the input power suddenly increases or decreases, or the output power suddenly increases or decreases, it will cause the ring gear 11 to rotate. Then, the ring gear 11 drives the heavy object to lift or lower through the rope, converting the work generated by the suddenly increased or decreased power into stored or released potential energy. In this way, the work generated by the suddenly increased or decreased power is not completely borne by the generator, but a large part of it is converted into a change in potential energy, so that the torque and speed of the generator can be kept with significantly reduced relative fluctuations, and the power curve fluctuates less. The radius of the rope relative to the center of the ring gear 11 determines the torque of the rope on the ring gear 11, that is, the tension F of the rope. In a set of fixed devices, F can be set as a fixed value in the balanced state. In the non-balanced state, it additionally includes the force generated by acceleration. The torque T = nFR, where n is the number of ropes and R is the perpendicular distance from the center of the ring gear to the rope tension, that is, the radius.

[0032] By setting up a planetary gear set, a cylinder 2, a rope, and an energy storage structure; the rope is wound around the cylinder 2. When the power fluctuates, the ring gear will rotate, and the cylinder rotates with the ring gear to make the rope move, converting the work originally borne by the generator into gravitational potential energy for storage; different diameter segments are set on the cylinder, corresponding to different torques; a large-torque constant segment, a continuously variable torque segment, and a small-torque constant segment. According to the control accuracy requirements, multiple segments with different torques can be further added. In the large-torque constant segment, it corresponds to the maximum rated power of the generator. In the small-torque constant segment, it corresponds to the minimum starting power of the generator. For a motor, a certain power corresponds to a certain torque and speed.

[0033] Embodiment 2: The difference from Embodiment 1 is that a bevel gear differential is used to replace the planetary gear set; the bevel gear differential is essentially a planetary gear mechanism. If the differential is used to replace the planetary gear set, the same effect can be achieved.

[0034] The above is only used to illustrate the technical solution of the present invention rather than to limit it. Any other modifications or equivalent replacements made by those of ordinary skill in the art to the technical solution of the present invention, as long as they do not depart from the spirit and scope of the technical solution of the present invention, shall be covered by the scope of the claims of the present invention.

Claims

1. Energy storage type generator power fluctuation smoothing device, characterized by: It comprises a planetary gear set, a cylinder (2) connected to the planetary gear set, a rope wound around the cylinder (2), and an energy storage structure connected to one end of the rope; The planetary gear set comprises a planet carrier (8), planet pinions (9), a sun gear (10) and a ring gear (11); There are at least two ropes, and the ropes are composed of a winding section, a separation section and a connection section connected in sequence from the starting end to the end; the starting end of the rope is fixedly connected to one end of the cylinder (2) connected to the planetary gear set or to the gear ring (11); the winding sections are synchronously wound side by side on the outside of the cylinder (2); and the separation section is tangent to the cylinder (2).

2. The energy storage type generator power fluctuation smoothing device according to claim 1 is characterized in that: The connecting section, starting from the end connected to the separating section, passes around the fixed pulley and is fixedly connected to the energy storage structure.

3. The energy storage type generator power fluctuation smoothing device according to claim 1 is characterized in that: A limiting groove (7) is provided in a spiral shape on the outside of the cylinder (2), and the rope is located in the limiting groove (7).

4. The energy storage type generator power fluctuation smoothing device according to claim 2 is characterized in that: The energy storage structure is a gravity energy storage structure or an elastic energy storage structure.

5. The energy storage type generator power fluctuation smoothing device according to claim 4 is characterized in that: The gravity energy storage structure comprises a weight connected to the separation section, and an upper elastic stopper (601) and a lower elastic stopper (602) respectively arranged at a distance above and below the weight.

6. The energy storage type generator power fluctuation smoothing device according to claim 1, characterized in that: The cylinder (2) and the gear ring (11) are integrally arranged or detachably fixedly connected.

7. The energy storage type generator power fluctuation smoothing device according to claim 1 is characterized in that: The cylinder (2) comprises at least a small torque constant section, a continuously variable torque section and a large torque constant section which are connected in sequence.

8. The energy storage type generator power fluctuation smoothing device according to claim 1 is characterized in that: A bearing (1) is arranged outside or inside the gear ring (11).

9. The energy storage type generator power fluctuation smoothing device according to claim 5, characterized in that: When there are two ropes, they include a first rope (301) and a second rope (302); the separated section of the first rope (301) and the separated section of the second rope (302) are symmetrically arranged outside the cylinder (2); the fixed pulley includes a first fixed pulley (401) and a second fixed pulley (402); and the weight includes a first weight (501) connected to the first rope (301) and a second weight (502) connected to the second rope (302).

10. The energy storage type generator power fluctuation smoothing device according to claim 1, characterized in that: The planetary gear set is replaced by a bevel gear differential.

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