A flywheel energy storage system

Abstract

The present invention discloses a flywheel energy storage system, wherein the flywheel energy storage system includes a housing, a flywheel assembly, a heat dissipation assembly and a magnetic fluid seal. The housing includes an upper shell and a lower shell that enclose a receiving cavity, the upper shell includes a first upper module and a second upper module that are connected in a chimeric manner, and the second upper module is provided with a receiving groove; the flywheel assembly is arranged in the receiving cavity, and includes a flywheel body and a flywheel shaft; the magnetic fluid seal is sleeved on the flywheel shaft; the heat dissipation assembly includes a heat dissipation sleeve and a heat dissipation plate, and a preset interval is provided between the heat dissipation plate and the flywheel shaft, and the outer peripheral surface of the flywheel shaft, the outer end surface of the magnetic fluid seal, the bottom wall of the receiving groove and the inner wall of the heat dissipation sleeve are enclosed to form a heat dissipation bridge, and a heat conducting medium is provided in the heat dissipation bridge. The present invention relates to the technical field of energy storage devices, and the heat dissipation efficiency of the flywheel energy storage system is improved by the radiation heat dissipation of the flywheel shaft by the heat dissipation plate and the contact heat dissipation of the flywheel shaft by the heat conducting medium in the heat dissipation bridge.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage devices, and in particular to a flywheel energy storage system. Background Art

[0002] The regulation of the power grid is an important part of the power transmission project. When the energy provided by the power grid is higher than the load requirements, the flywheel energy storage system in the power grid works in the charging state, and the controller controls the motor to drive the flywheel to rotate, converting the electrical energy into mechanical energy for storage. When the energy provided by the power grid is lower than the load requirements, the flywheel energy storage system works in the power generation state under the control of the controller, converting the mechanical energy into electrical energy, and supplying the load after power conversion.

[0003] Since the flywheel energy storage system is in a vacuum environment and the high-speed running flywheel body generates high heat, if the temperature is too high, the life span will be rapidly reduced, and it may even cause failure or burning, which will affect the working process of the flywheel shaft. Therefore, the heat dissipation problem of the flywheel shaft plays a vital role in ensuring the normal operation of the flywheel energy storage system. In the related technology, the common heat dissipation method of the flywheel energy storage system is to process the outer shell into a spiral water channel, and then use the compressor to consume electricity to allow the fluid to flow in the water channel, thereby achieving the purpose of heat dissipation of the flywheel shaft. However, this method is limited by the specific shape of the water channel, which makes the heat dissipation of the flywheel shaft unstable, and there is still a certain distance between the water channel and the flywheel shaft, making it difficult to quickly dissipate the heat of the flywheel shaft, affecting the heat dissipation efficiency and working stability of the flywheel energy storage system. Summary of the invention

[0004] The main purpose of the present invention is to provide a flywheel energy storage system, aiming to improve the deficiencies of the above-mentioned prior art and further improve the heat dissipation efficiency of the flywheel energy storage system.

[0005] To achieve the above-mentioned purpose, the flywheel energy storage system proposed in the present invention includes a housing, a flywheel assembly, a magnetic fluid seal and a heat dissipation assembly. The housing comprises an upper shell and a lower shell which are matched and connected, the upper shell and the lower shell are enclosed to form a receiving cavity, the upper shell comprises a first upper module and a second upper module, the second upper module is embedded in the middle of the first upper module, and the inner wall surface of the second upper module is concavely provided with a receiving groove facing the receiving cavity; the flywheel assembly is arranged in the receiving cavity, the flywheel assembly comprises a flywheel body and a flywheel shaft, the flywheel body is fixedly connected to the flywheel shaft, and the flywheel shaft at least partially extends into the receiving groove; the magnetic fluid seal is sleeved on the flywheel shaft and at least partially arranged in the receiving groove; the heat dissipation assembly comprises a heat dissipation sleeve and a heat dissipation plate, the heat dissipation sleeve is at least partially sleeved on the magnetic fluid seal, the heat dissipation plate is arranged on the second upper module, and a preset interval is set between the heat dissipation plate and the flywheel shaft, the outer peripheral surface of the flywheel shaft, the outer end surface of the magnetic fluid seal, the bottom wall surface of the receiving groove and the inner wall surface of the heat dissipation sleeve are enclosed to form a heat dissipation bridge, and a heat conducting medium is arranged in the heat dissipation bridge.

[0006] In one embodiment of the present invention, the second upper module is provided with a liquid inlet hole and a liquid outlet hole corresponding to the heat dissipation sleeve, the heat dissipation sleeve is provided with a heat conduction groove, the heat conduction groove is spirally extended around the axis of the heat dissipation sleeve, the flywheel shaft is formed with a through heat conduction hole, the heat conduction hole is at least partially exposed to the heat dissipation bridge, the liquid inlet hole, the heat conduction groove, the heat conduction hole, the heat dissipation bridge and the liquid outlet hole are interconnected to form a heat dissipation channel.

[0007] In one embodiment of the present invention, the second upper module comprises a second upper mold base and a second upper mold core. The second upper mold base is embedded in the middle of the first upper module, and the inner wall surface of the second upper mold base is concavely provided with a receiving groove facing the receiving cavity and is provided with the liquid inlet hole and the liquid outlet hole; the second upper mold core is embedded in the middle of the second upper mold base, and the liquid inlet hole and the liquid outlet hole are arranged at intervals on the side circumference of the second upper mold core, and the second upper mold core is at least partially exposed on the bottom wall surface of the receiving groove and abuts against the inner wall surface of the heat dissipation sleeve, and the second upper mold core is close to the wall surface of the flywheel shaft, the wall surface of the magnetic fluid seal facing the second upper mold core, the outer peripheral surface of the flywheel shaft and the inner peripheral surface of the heat dissipation sleeve form a heat dissipation bridge.

[0008] In one embodiment of the present invention, the heat sink includes an extension portion and a radiation portion. The extension portion is sandwiched between the second upper module and the heat sink, and has a first heat dissipation end surface abutting against the outer peripheral surface of the heat sink and a second heat dissipation end surface abutting against the inner wall surface of the accommodating groove; the radiation portion is arranged on a side of the extension portion away from the accommodating groove and extends toward the flywheel shaft, and a side wall surface of the radiation portion close to the accommodating groove abuts against the heat sink, and the preset interval is arranged between the radiation portion and the flywheel shaft.

[0009] In one embodiment of the present invention, a heat dissipation neck is protruding from the outer circumference of the flywheel shaft, and the cross-sectional area of ​​the heat dissipation neck gradually decreases from the end far away from the accommodating groove to the end close to the accommodating groove; the end surface shape of the radiation portion close to the heat dissipation neck is set to correspond to the shape of the outer circumference of the heat dissipation neck, and the preset interval is set between the radiation portion and the outer circumference of the heat dissipation neck.

[0010] In an embodiment of the present invention, a ratio of a radius difference between the heat dissipation neck and the heat dissipation plate to the preset interval is greater than or equal to 5.

[0011] In one embodiment of the present invention, a ratio of an orthographic projection area of ​​the heat dissipation neck on the heat dissipation plate to a radial cross-sectional area of ​​the heat dissipation neck is greater than or equal to 10.

[0012] In one embodiment of the present invention, the heat dissipation component further includes a heat dissipation layer, the heat dissipation layer is coated on the outer peripheral surface of the radiation portion, and the preset interval is arranged between the heat dissipation layer and the flywheel shaft.

[0013] In one embodiment of the present invention, there are multiple protruding portions, and the multiple protruding portions are arranged at intervals around the axis of the flywheel shaft.

[0014] In one embodiment of the present invention, the heat conducting medium is a magnetic fluid.

[0015] The flywheel energy storage system proposed in the technical solution of the present invention forms an accommodating cavity by the mating connection of the upper shell and the lower shell in the outer shell, and the accommodating groove on the inner wall of the upper shell facing the accommodating cavity limits the movement of the flywheel shaft, and then the heat transfer during the operation of the flywheel energy storage system is guided by the heat dissipation component sandwiched between the upper shell and the flywheel shaft. Specifically, the flow direction of the heat-conducting medium is guided by the heat dissipation channel, and the flow position of the heat-conducting medium is constrained by the magnetic seal, thereby transferring the heat generated by the flywheel shaft during the operation of the flywheel assembly, and then the radiation part and the guide part of the heat dissipation component are set to the shape corresponding to the flywheel shaft, so that the heat of the flywheel shaft is further transferred in the form of radiation heat transfer, thereby improving the heat dissipation efficiency and working stability of the flywheel energy storage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0017] Figure 1 It is a structural schematic diagram of an embodiment of a flywheel energy storage system of the present invention;

[0018] Figure 2 for Figure 1 Enlarged view of part A in the middle;

[0019] Figure 3 A schematic diagram of the flow direction of the heat transfer medium of an embodiment of a flywheel energy storage system of the present invention;

[0020] Figure 4 It is a schematic diagram of the structure of the flywheel rotating shaft in one embodiment of the flywheel energy storage system of the present invention;

[0021] Figure 5 for Figure 3 Enlarged view of middle part B;

[0022] Figure 6 Schematic diagram of the structure of the heat sink in one embodiment of the flywheel energy storage system of the present invention.

[0023] Description of Figure Numbers:

[0024] Serial number name Serial number name 100 Flywheel energy storage system 10 shell 11 Upper shell 111 First upper module 113 Second upper module 113a Second upper die seat 113b Second upper mold core 113c Liquid inlet hole 113d Liquid outlet 115 Storage tank 12 Accommodation cavity 13 Lower shell 30 Flywheel assembly 31 Flywheel body 33 Flywheel shaft 331 Heat sink neck 333 Thermal vias 50 Heat dissipation components 51 Cooling sleeve 511 Heat sink 53 Heat sink 531 Extension 533 Radiation Department 55 Thermal bridge 70 Magnetic fluid seals

[0025] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0028] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text is to include three parallel solutions. Taking "A and / or B as an example", it includes solution A, or solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0030] The regulation of the power grid is an important part of the power transmission project. When the energy provided by the power grid is higher than the load requirements, the flywheel energy storage system in the power grid works in the charging state, and the controller controls the motor to drive the flywheel to rotate, converting the electrical energy into mechanical energy for storage. When the energy provided by the power grid is lower than the load requirements, the flywheel energy storage system works in the power generation state under the control of the controller, converting the mechanical energy into electrical energy, and supplying the load after power conversion.

[0031] Since the flywheel energy storage system is in a vacuum environment and the high-speed running flywheel body generates high heat, if the temperature is too high, the life span will be rapidly reduced, and it may even cause failure or burning, which will affect the working process of the flywheel shaft. Therefore, the heat dissipation problem of the flywheel shaft plays a vital role in ensuring the normal operation of the flywheel energy storage system. In the related technology, the common heat dissipation method of the flywheel energy storage system is to process the outer shell into a spiral water channel, and then use the compressor to consume electricity to allow the fluid to flow in the water channel, thereby achieving the purpose of heat dissipation of the flywheel shaft. However, this method is limited by the specific shape of the water channel, which makes the heat dissipation of the flywheel shaft unstable, and there is still a certain distance between the water channel and the flywheel shaft, making it difficult to quickly dissipate the heat of the flywheel shaft, affecting the heat dissipation efficiency and working stability of the flywheel energy storage system.

[0032] In order to improve the deficiencies of the above-mentioned prior art, Figures 1 to 6The technical solution of the present invention proposes a flywheel energy storage system 100, including a housing 10, a flywheel assembly 30, a magnetic fluid seal 70 and a heat dissipation assembly 50. The housing 10 includes an upper shell 11 and a lower shell 13 that are connected in abutment, and the upper shell 11 and the lower shell 13 enclose a receiving chamber 12. The upper shell 11 includes a first upper module 111 and a second upper module 113. The second upper module 113 is embedded in the middle of the first upper module 111, and the inner wall surface of the second upper module 113 is recessed with a receiving groove 115 facing the receiving chamber 12; the flywheel assembly 30 is disposed in the receiving chamber 12, and the flywheel assembly 30 includes a flywheel body 31 and a flywheel shaft 33. The flywheel body 31 is fixedly connected to the flywheel shaft 33, and at least part of the flywheel shaft 33 is fixedly connected to the flywheel shaft 33. The magnetic fluid seal 70 is sleeved on the flywheel shaft 33 and at least partially arranged in the accommodating groove 115; the heat dissipation component 50 includes a heat dissipation sleeve 51 and a heat dissipation plate 53, the heat dissipation sleeve 51 is at least partially sleeved on the magnetic fluid seal 70, the heat dissipation plate 53 is arranged on the second upper module 113, and a preset interval is set between the flywheel shaft 33, the outer peripheral surface of the flywheel shaft 33, the outer end surface of the magnetic fluid seal 70, the bottom wall of the accommodating groove 115 and the inner wall of the heat dissipation sleeve 51 are surrounded to form a heat dissipation bridge 55, and a heat-conducting medium is set in the heat dissipation bridge 55.

[0033] It can be understood that the accommodating chamber 12 is formed by the matching connection of the upper shell 11 and the lower shell 13 in the housing 10, and the upper shell 11 is provided with a second upper module 113, and the inner wall surface of the upper module 113 faces the accommodating groove 115 concavely arranged in the accommodating chamber 12 to limit the movement of the flywheel shaft 33. On the one hand, a preset interval is set between the heat dissipation plate 53 in the heat dissipation assembly 50 and the flywheel shaft 33, and the heat generated by the flywheel shaft 33 during the working process is transferred in a corresponding manner of radiation heat transfer; on the other hand, the outer side of the flywheel shaft 33 is The peripheral surface, the outer end surface of the magnetic fluid seal 70, the bottom wall surface of the accommodating groove 115 and the inner wall surface of the heat dissipation sleeve 51 are combined to form a heat dissipation bridge 55. The heat-conducting medium arranged in the heat dissipation bridge 55 absorbs the heat generated by the flywheel shaft 33 during operation through contact with the outer peripheral surface of the flywheel shaft 33, and guides the heat to be transferred toward the second upper module 113 and the heat dissipation sleeve 51 through the inner wall surface of the heat dissipation sleeve 51 and the bottom wall surface of the accommodating groove 115. In this way, the heat dissipation efficiency and working stability of the flywheel energy storage system 100 are further improved.

[0034] It is understandable that during the operation of the flywheel energy storage system 100, the flywheel assembly 30 will experience high centrifugal force and vibration, which will exert a large force on the heat dissipation assembly 50, and the heat-conducting medium may leak or penetrate into the flywheel assembly 30. The cooling effect will be reduced in this case, and may even affect the operation safety of the flywheel energy storage system 100. By activating the magnetic fluid seal 70, a magnetic field is created to form a magnetically sealed area in the heat dissipation bridge 55, and the heat-conducting medium is confined inside the heat dissipation bridge 55. It can only circulate in the heat dissipation bridge 55 and cannot leak or enter the external environment. In this way, it is possible to ensure that the heat-conducting medium in the heat dissipation channel successfully completes the heat dissipation process without contacting the flywheel shaft 33 that rotates rapidly during operation, thereby further increasing the working stability of the flywheel energy storage system 100.

[0035] In one embodiment of the present invention, in conjunction with reference Figures 1 to 5 The second upper module 113 is provided with a liquid inlet hole 113c and a liquid outlet hole 113d corresponding to the heat dissipation sleeve 51, the heat dissipation sleeve 51 is provided with a heat conduction groove 511, and the heat conduction groove 511 is spirally extended around the axis of the heat dissipation sleeve 51, and the flywheel shaft 33 is formed with a through heat conduction hole 333, and the heat conduction hole 333 is at least partially exposed to the heat dissipation bridge 55. The liquid inlet hole 113c, the heat conduction groove 511, the heat conduction hole 333, the heat dissipation bridge 55 and the liquid outlet hole 113d are interconnected to form a heat dissipation channel.

[0036] It can be understood that the spirally extending heat-conducting groove 511 and the heat-conducting holes 333 provided through the flywheel shaft 33 increase the flow length of the heat-conducting medium and the contact area between the heat-conducting medium and the various components, so that the heat generated by the flywheel shaft 33 during operation can be fully transferred to the heat-conducting medium flowing in the heat dissipation channel, thereby increasing the time and opportunity of heat conduction and further improving the heat dissipation efficiency of the flywheel energy storage system 100.

[0037] It is understandable that the spirally extending heat-conducting groove 511 can also reduce the flow resistance of the heat-conducting medium in the heat-conducting groove 511, thereby improving the speed and flow efficiency of the heat-conducting medium. The spiral heat-conducting groove 511 causes the heat-conducting medium to generate a rotational motion in the channel, reducing the area and time of contact between the heat-conducting medium and the inner wall surface of the heat-conducting groove 511, thereby reducing friction and energy loss, and further improving the heat dissipation efficiency and energy-saving effect of the flywheel energy storage system 100.

[0038] It should be noted that, in conjunction with the reference Figure 3During the operation of the flywheel energy storage system 100, the heat-conducting medium can be replenished through the liquid inlet 113c, and the used heat-conducting medium can be discharged through the liquid outlet 113d. The heat-conducting medium continuously flows between the interconnected liquid inlet 113c, the heat-conducting groove 511, the heat-conducting hole 333, the heat dissipation bridge 55 and the liquid outlet 113d. During the flow, the heat-conducting medium contacts the outer peripheral surface of the flywheel shaft 33 and the side wall surface of the heat-conducting hole 333 through which the flywheel shaft 33 is arranged. The heat generated by the flywheel shaft 33 during operation will The heat is absorbed by the heat-conducting medium from the above two contact points, and then circulates in the heat dissipation channel after absorbing the heat. The absorbed heat will be transferred toward other wall surfaces that it contacts and constitute the heat dissipation channel during the flow process, such as the side wall surface of the heat-conducting groove 511, the inner wall surface of the heat dissipation sleeve 51 or the bottom wall surface of the accommodating groove 115, and then the heat dissipation sleeve 51 and the second upper module 113 further release the heat to the outside, thereby achieving the heat dissipation effect of the flywheel energy storage system 100 and further improving the heat dissipation efficiency of the flywheel energy storage system 100.

[0039] It is understandable that the material of the heat-conducting medium can be a material with good rheological properties and thermal conductivity such as air, water, ethanol or liquid metal, and this application does not make specific restrictions on this. Depending on the heat-conducting medium, different devices can be set to provide driving force for the heat-conducting medium to work normally in the heat dissipation channel. Specifically, when the heat-conducting medium is a gas, an air duct can be set in the flywheel energy storage system 100 and correspondingly connected to the liquid inlet hole 113c and the liquid outlet hole 113d, so as to guide the gaseous heat-conducting medium to circulate in the heat dissipation channel under the drive of wind and take away the heat generated during the operation of the flywheel shaft 33; when the heat-conducting medium is a liquid, a pump can be set in the flywheel energy storage system 100 and correspondingly connected to the liquid inlet hole 113c and the liquid outlet hole 113d, and the liquid heat-conducting medium is driven by the pump to circulate in the heat dissipation channel and take away the heat generated during the operation of the flywheel shaft, and this application does not make specific restrictions on this.

[0040] In one embodiment of the present invention, in conjunction with reference Figures 1 to 3 As shown, the second upper mold block 113 includes a second upper mold base 113a and a second upper mold core 113b. The second upper mold base 113a is embedded in the middle of the first upper mold block 111, and the inner wall surface of the second upper mold base 113a is concavely provided with a receiving groove 115 facing the receiving cavity 12, and is provided with a liquid inlet hole 113c and a liquid outlet hole 113d; the second upper mold core 113b is embedded in the middle of the second upper mold base 113a, and the liquid inlet hole 113c and the liquid outlet hole 113d are arranged at intervals on the side of the second upper mold core 113b. The second upper mold core 113b is at least partially exposed to the bottom wall of the receiving groove 115 and abuts against the inner wall of the heat dissipation sleeve 51. The wall surface of the second upper mold core 113b close to the flywheel shaft 33, the wall surface of the magnetic fluid seal 70 facing the second upper mold core 113b, the outer peripheral surface of the flywheel shaft 33 and the inner peripheral surface of the heat dissipation sleeve 51 enclose to form a heat dissipation bridge 55.

[0041] It is understandable that the second upper module 113 is set as the second upper mold base 113a and the second upper mold core 113b, and the liquid inlet hole 113c, the liquid outlet hole 113d or the second upper mold base 113a and the second upper mold core 113b provided on the second upper mold base 113a can be replaced respectively when the body thereof is damaged. On the other hand, by disassembling the second upper mold core 113b alone, the heat dissipation bridge 55, the magnetic fluid seal 70, the flywheel shaft 33, and the heat dissipation sleeve 51 can be exposed to the outside world, which further improves the convenience of inspection and maintenance of the second upper module 113 and the flywheel energy storage system 100, that is, further improves the flexibility and service life of the flywheel energy storage system 100.

[0042] It can be understood that the portion of the second upper mold core 113b exposed on the bottom wall of the accommodating groove 115 is clamped on the inner wall of the heat dissipation sleeve 51, which prevents the heat dissipation sleeve 51 from being displaced when subjected to external force or vibration and affecting the flow shape of the heat dissipation bridge 55 and the heat dissipation channel, thereby further improving the working stability of the flywheel energy storage system 100.

[0043] In one embodiment of the present invention, in conjunction with reference Figures 1 to 3 and Figure 6 The heat sink 53 includes an insertion portion 531 and a radiation portion 533. The insertion portion 531 is sandwiched between the second upper module 113 and the heat sink 51, and has a first heat sink end surface abutting against the outer peripheral surface of the heat sink 51 and a second heat sink end surface abutting against the inner wall surface of the accommodating groove 115; the radiation portion 533 is arranged on a side of the insertion portion 531 away from the accommodating groove 115, and extends toward the flywheel shaft 33, and a side wall surface of the radiation portion 533 close to the accommodating groove 115 abuts against the heat sink 51, and a preset interval is arranged between the radiation portion 533 and the flywheel shaft 33.

[0044] It can be understood that the first heat dissipation end surface and the second heat dissipation end surface respectively abut the outer peripheral surface of the heat dissipation sleeve 51 and the inner wall surface of the accommodating groove 115, so as to guide the heat generated by the flywheel shaft 33 during the rotation process through the outer peripheral surface of the flywheel shaft 33, the first heat dissipation end surface, the outer peripheral surface of the heat dissipation sleeve 51, the second heat dissipation end surface and the inner wall surface of the accommodating groove 115 during the operation of the flywheel energy storage system 100, and finally transfer the heat from the accommodating groove 115 toward the shell and the outside, so as to achieve the heat dissipation effect and further improve the heat dissipation efficiency of the flywheel energy storage system 100.

[0045] In one embodiment of the present invention, in conjunction with reference Figures 1 to 5A heat dissipation neck 331 is convexly provided on the outer circumference of the flywheel shaft 33, and the cross-sectional area of ​​the heat dissipation neck 331 gradually decreases from the end far away from the accommodating groove 115 to the end close to the accommodating groove 115; the end surface shape of the radiation portion 533 close to the heat dissipation neck 331 is set corresponding to the shape of the outer circumference of the heat dissipation neck 331, and a preset interval is set between the radiation portion 533 and the outer circumference of the heat dissipation neck 331.

[0046] It is understandable that the heat generated by the flywheel shaft 33 during operation can be radiated toward the radiation portion 533 at the heat dissipation neck 331. Radiative heat dissipation refers to the process by which an object dissipates heat by transferring energy through radiation. When the temperature of an object is higher than the temperature of the surrounding environment, it transfers heat energy to the surrounding environment through thermal radiation. The shape of the end face of the radiation portion 533 close to the heat dissipation neck 331 is set to correspond to the shape of the outer peripheral surface of the heat dissipation neck 331, so that the surface area of ​​the heat exchange between the heat dissipation neck 331 and the radiation portion 533 can be as large as possible, thereby improving the heat dissipation efficiency of the flywheel energy storage system 100.

[0047] It is understandable that the cross-sectional shape of the heat dissipation neck 331 can be stepped, and in this case, the cross-sectional shape of the radiation portion 533 is correspondingly set to be stepped. In this way, without increasing the volume of the heat dissipation neck 331, the heat radiation area thereof relative to the radiation portion 533 is increased as much as possible, that is, the heat dissipation efficiency of the flywheel energy storage system 100 is further increased.

[0048] In one embodiment of the present invention, a ratio of a radius difference between the heat dissipation neck 331 and the heat dissipation plate 53 to a preset interval is greater than or equal to 5.

[0049] It can be understood that, since the accommodating chamber 12 is usually a vacuum environment, radiation is the main heat dissipation path for the heat received by the flywheel shaft 33 during the operation of the flywheel energy storage system 100, and the radiation can be equivalent to radiation thermal resistance. The smaller the radiation thermal resistance, the stronger the heat dissipation capacity. Therefore, according to the radiation thermal resistance principle, under the condition of a certain temperature difference, it has a direct relationship with the area and the radiation angle coefficient, that is, the larger the radiation angle coefficient, the larger the radiation area, the larger the denominator, and the smaller the radiation thermal resistance. However, the radiation angle coefficient is directly related to the radiation area and the radiation distance. In some cases, considering that the flywheel shaft 33 will produce a large axial displacement of about 1mm when heated, it is necessary to ensure that it is not hindered by other structures during the rotation process, and it can also exert the maximum heat dissipation performance. It is necessary to make the spacing between them about 0.5mm and 2.5mm to have a better heat dissipation effect. Therefore, it is usually made that: (the radius of the radiation plate surface on the heat dissipation plate 53 minus the radius of the flywheel heat dissipation axis) / preset spacing is greater than or equal to 5. Such a setting further improves the heat dissipation efficiency of the flywheel energy storage system 100.

[0050] It should be noted that, in a preferred embodiment, in order to further reduce the influence of frictional heat generated between the flywheel shaft 33 and the heat sink 53 on the heat sink 51, the heat sink 53 or the flywheel shaft 33, the spacing distance between the flywheel shaft 33 and the heat sink 53 is set to 0.5mm~2.5mm. In this way, it can ensure that the two have good thermal radiation efficiency and avoid contact due to thermal expansion, thereby further improving the heat dissipation efficiency and working stability of the flywheel energy storage system 100.

[0051] In one embodiment of the present invention, the ratio of the orthographic projection area of ​​the heat dissipation neck 331 on the heat dissipation plate 53 to the radial cross-sectional area of ​​the heat dissipation neck 331 is greater than or equal to 10.

[0052] It can be understood that the positive projection area of ​​the heat sink neck 331 on the heat sink 53 is set to be more than 10 times the cross-sectional area of ​​the flywheel shaft 33, which is equivalent to setting a heat sink 53 with a larger cross-sectional area on the flywheel shaft 33. In this way, combined with the aforementioned radiation efficiency analysis, the solution adopted in this application can achieve good heat dissipation effect.

[0053] In one embodiment of the present invention, the heat dissipation component 50 further includes a heat dissipation layer, which is coated on the outer peripheral surface of the radiation portion 533 , and a preset interval is provided between the heat dissipation layer and the flywheel shaft 33 .

[0054] It is understandable that the material of the heat dissipation layer is a material with high thermal emissivity, so that the efficiency of heat radiation conduction between the side wall surface of the flywheel shaft 33 and the outer peripheral surface of the radiation portion 533 with a preset interval from the heat dissipation layer can be further improved. Specifically, in a preferred embodiment, the material of the heat dissipation layer can be a material that uses GJT series high-emissivity ceramic coatings or HT series high-emissivity coatings to make the surface emissivity reach about 0.9; in a preferred embodiment, the thickness of the heat dissipation layer is 0.2m, so that the disadvantage of the heat dissipation layer being unable to dissipate heat when the thickness is too low is avoided, and the working failure caused by the heat dissipation layer being unable to be transferred to the outside world when the heat dissipation layer is too thick is avoided, and the working stability and heat dissipation efficiency of the flywheel energy storage system 100 are further increased.

[0055] In one embodiment of the present invention, in conjunction with reference Figures 1 to 3 and Figure 6 There are multiple protruding portions 531 , and the multiple protruding portions 531 are arranged at intervals around the axis of the flywheel shaft 33 .

[0056] It can be understood that the multiple insertion portions 531 arranged at intervals around the axis of the flywheel shaft 33 further avoid the deformation of the insertion portions 531 caused by thermal stress during the operation of the flywheel energy storage system 100, thereby further increasing the working stability of the flywheel energy storage system 100.

[0057] In one embodiment of the present invention, the heat conducting medium is a magnetic fluid.

[0058] It should be noted that magnetic fluid is a kind of medium containing tiny magnetic particles (usually nanometer-level particles). These magnetic particles can be rapidly magnetized and arranged under the action of an external magnetic field, thereby changing the flow properties of the fluid. When the magnetic fluid is used as a heat-conducting medium, the flow of the fluid can be controlled by adjusting the external magnetic field through the magnetic fluid seal 70, thereby realizing the transfer and dispersion of heat. Specifically, when the magnetic fluid is subjected to the action of a magnetic field, the magnetic particles inside the fluid will form a chain or mesh structure, thereby increasing the viscosity and thermal conductivity of the fluid. Compared with traditional heat-conducting media, magnetic fluids can achieve adjustable flow under the action of an external magnetic field, thereby providing higher heat dissipation efficiency and flexibility. In addition, the magnetic fluid heat dissipation system has the characteristics of simple structure, small size, and light weight, and is suitable for occasions where conventional heat dissipation equipment cannot meet the requirements. The heat dissipation efficiency of the flywheel energy storage system 100 is further improved.

[0059] It should be noted that during the long-term use of the magnetic fluid seal 70, the magnetic fluid inside it may change its own magnetic moment due to magnetization and magnetic domain rearrangement, resulting in energy loss; it may also cause wear due to contact and friction between magnetic particles and non-magnetic materials or other solid surfaces. Both of the above may affect the working effect of the magnetic fluid seal 70. When the heat-conducting medium is set to be a magnetic fluid, it can supplement the magnetic fluid inside the magnetic fluid seal 70 at the contact point between the heat dissipation channel and the magnetic fluid seal 70, further improving the working stability and service life of the flywheel energy storage system 100.

[0060] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A flywheel energy storage system, characterized in that: The flywheel energy storage system comprises: A housing, the housing comprising an upper housing and a lower housing connected to each other, the upper housing and the lower housing enclose a receiving cavity, the upper housing comprises a first upper module and a second upper module, the second upper module is embedded in the middle of the first upper module, and an receiving groove is concavely formed on the inner wall of the second upper module facing the receiving cavity; A flywheel assembly, the flywheel assembly is arranged in the accommodating cavity, the flywheel assembly comprises a flywheel body and a flywheel shaft, the flywheel body is fixedly connected to the flywheel shaft, and the flywheel shaft at least partially extends into the accommodating groove; A magnetic fluid seal, which is sleeved on the flywheel shaft and at least partially disposed in the accommodating groove; and A heat dissipation component, the heat dissipation component includes a heat dissipation sleeve and a heat dissipation plate, the heat dissipation sleeve is at least partially sleeved on the magnetic fluid seal, the heat dissipation plate is arranged on the second upper module, and a preset interval is set between the heat dissipation plate and the flywheel shaft, the outer peripheral surface of the flywheel shaft, the outer end surface of the magnetic fluid seal, the bottom wall of the accommodating groove and the inner wall of the heat dissipation sleeve are surrounded to form a heat dissipation bridge, and a heat conducting medium is arranged in the heat dissipation bridge; The second upper module is provided with a liquid inlet and a liquid outlet corresponding to the heat dissipation sleeve, the heat dissipation sleeve is provided with a heat conduction groove, the flywheel shaft is formed with a through heat conduction hole, the heat conduction hole is at least partially exposed to the heat dissipation bridge, the liquid inlet, the heat conduction groove, the heat conduction hole, the heat dissipation bridge and the liquid outlet are interconnected to form a heat dissipation channel; The heat conducting medium is a magnetic fluid.

2. The flywheel energy storage system according to claim 1, characterized in that: The heat-conducting groove is extended in a spiral shape around the axis of the heat-dissipating sleeve.

3. The flywheel energy storage system according to claim 2, characterized in that: The second upper module comprises: A second upper mold base, wherein the second upper mold base is embedded in the middle of the first upper mold block, and an inner wall surface of the second upper mold base is concavely provided with an accommodating groove facing the accommodating cavity and is provided with the liquid inlet hole and the liquid outlet hole; and The second upper mold core is embedded in the middle of the second upper mold base, the liquid inlet hole and the liquid outlet hole are arranged at intervals on the side of the second upper mold core, the second upper mold core is at least partially exposed on the bottom wall of the accommodating groove, and abuts against the inner wall of the heat dissipation sleeve, the second upper mold core is close to the side wall of the flywheel shaft, the side wall of the magnetic fluid seal facing the second upper mold core, the outer peripheral surface of the flywheel shaft and the inner peripheral surface of the heat dissipation sleeve form a heat dissipation bridge.

4. The flywheel energy storage system according to claim 1, characterized in that: The heat sink comprises: an extending portion, the extending portion being sandwiched between the second upper module and the heat dissipation sleeve and having a first heat dissipation end surface abutting against an outer peripheral surface of the heat dissipation sleeve and a second heat dissipation end surface abutting against an inner wall surface of the accommodating groove; and The radiation part is arranged on the side of the extending part away from the accommodating groove and extends toward the flywheel shaft. The radiation part abuts against the heat dissipation sleeve on a side wall close to the accommodating groove, and the preset interval is arranged between the radiation part and the flywheel shaft.

5. The flywheel energy storage system according to claim 4, characterized in that: A heat dissipation neck is convexly provided on the outer peripheral surface of the flywheel shaft, and the cross-sectional area of ​​the heat dissipation neck gradually decreases from an end away from the accommodating groove to an end close to the accommodating groove; The shape of the end surface of the radiation portion close to the heat dissipation neck is arranged to correspond to the shape of the outer peripheral surface of the heat dissipation neck, and the preset interval is arranged between the radiation portion and the outer peripheral surface of the heat dissipation neck.

6. The flywheel energy storage system according to claim 5, characterized in that: A ratio of a radius difference between the heat dissipation neck and the heat dissipation plate to the preset interval is greater than or equal to 5.

7. The flywheel energy storage system according to claim 5, characterized in that: The ratio of the orthographic projection area of ​​the heat dissipation neck on the heat dissipation plate to the radial cross-sectional area of ​​the heat dissipation neck is greater than or equal to 10.

8. The flywheel energy storage system according to claim 5, characterized in that: The heat dissipation component further includes a heat dissipation layer, which is coated on the outer peripheral surface of the radiation portion, and the preset interval is arranged between the heat dissipation layer and the flywheel shaft.

9. The flywheel energy storage system according to claim 4, characterized in that: There are multiple protruding portions, and the multiple protruding portions are arranged at intervals around the axis of the flywheel shaft.

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