TWI763610B - Flywheel power storage system - Google Patents

Abstract

The disclosure relates to a flywheel power storage system, including an outer casing, a flywheel, a shaft, an inner rotor, an outer rotor, and a stator. The outer casing has a vacuum chamber. The flywheel, shaft, and inner rotor are located within the vacuum chamber. The shaft disposed through the flywheel. The inner rotor is fixed to the shaft. The outer rotor is located outside the vacuum chamber and surrounds the inner rotor. The stator is located outside the vacuum chamber and surrounds the outer rotor.

Description

Flywheel Energy Storage System

The present invention relates to an electric motor, in particular to a flywheel energy storage system.

A flywheel energy storage (FES) system is a method of energy storage, which mainly uses acceleration and has a rotating shaft.

A typical flywheel energy storage system includes a cavity, which is equipped with a flywheel and a motor unit for driving it to rotate. The motor unit can be used as a device for energy output and input, and can receive power input in the form of a motor to drive the flywheel to rotate. When the flywheel rotates to a very high speed, the energy can be stored in the system in the form of rotational kinetic energy, and the motor unit can also change the energy stored in the rotation of the flywheel into electrical output in the form of a generator.

It can be seen that the flywheel energy storage system can directly convert mechanical energy and electrical energy, and because the speed of the flywheel can be rapidly increased to quickly absorb or release energy, its power is larger than other energy storage devices. . For example, compared with general chemical batteries (such as lead-acid batteries), the power density of flywheel energy storage systems is significantly higher, making flywheel energy storage systems more suitable than chemical batteries in some occasions where fast energy storage is required, such as In occasions such as wind power plants with large changes in air volume, or wave power plants with large changes in water volume, devices that quickly absorb or release energy are required to stabilize voltage or electricity; alternatively, the flywheel energy storage system is also suitable for motor vehicles. The flywheel quickly absorbs braking energy or deceleration energy, and quickly releases energy when starting; or, due to the fast energy storage characteristics of the flywheel energy system, more and more charging stations have introduced the technology of the flywheel energy system to greatly shorten the charging time. time required for the vehicle. The aforementioned reasons and advantages make the flywheel energy storage system gradually attract the attention of the industry.

However, current flywheel energy storage systems still have shortcomings. For example, in order to drive the flywheel, the motor and the flywheel of the existing flywheel energy storage system are arranged in a vacuum chamber, but when the motor is running, the stator coil and other components will generate high heat. If it cannot be eliminated, it is easy to accumulate too much heat. Burning can even seriously affect other surrounding components, such as damage to peripheral circuits, or thermal stress to surrounding magnetic materials, thereby affecting the reliability and stability of the overall system. For this reason, some manufacturers have adopted air-cooled tubes or liquid-cooled tubes through the casing to dissipate heat from the stator coil, but this approach will seriously affect the air tightness and increase the resistance of the flywheel to rotate.

Accordingly, how to solve the heat dissipation problem of the traditional flywheel energy storage system without affecting the vacuum tightness of the flywheel energy storage system is indeed one of the key research projects in the industry at present.

In view of this, the present invention provides a flywheel energy storage system, which can isolate the heat generating element from the vacuum chamber, so as to avoid the traditional heat dissipation means that would affect the vacuum tightness.

A flywheel energy storage system disclosed according to an embodiment of the present invention includes a casing, a flywheel, a rotating shaft, an inner rotor, an outer rotor and a stator. The housing has a vacuum chamber. The flywheel is arranged in the vacuum chamber. The rotating shaft is arranged in the vacuum chamber and passes through the flywheel. The inner rotor is arranged in the vacuum chamber and fixed on the rotating shaft. The outer rotor is arranged outside the vacuum chamber. The outer rotor surrounds the inner rotor and can magnetically act on the inner rotor. The stator is located outside the vacuum chamber. The stator surrounds the outer rotor and can be used to drive the outer rotor.

According to the flywheel energy storage system disclosed in the foregoing embodiments of the present invention, since the stator that can be used to drive the outer rotor is located outside the vacuum chamber, and the inner rotor that interacts with the outer rotor is located inside the vacuum chamber, the outer rotor and the inner rotor can A magnetic shaft coupling is formed that drives the shaft and the flywheel by magnetic force, and drives the shaft and the flywheel without mechanical contact, so that the shaft and the flywheel can rotate without resistance.

In addition, the stator of the electric motor that generates heat through current is excluded from the vacuum chamber. This configuration enables the flywheel energy storage system to isolate the components that mainly generate heat energy during operation from the vacuum chamber, so that the flywheel energy storage system can avoid the use of Heat dissipation, which traditionally affects vacuum tightness, helps ensure the air tightness required for flywheel operation.

The above description of the disclosure of the present invention and the description of the following embodiments are used to demonstrate and explain the spirit and principle of the present invention, and provide further explanation of the scope of the patent application of the present invention.

The detailed features and advantages of the present invention will be described in detail in the following embodiments, the content of which is sufficient to enable any person skilled in the relevant art to understand the technical content of the present invention and implement accordingly, but does not limit the scope of the present invention in any point of view.

The following embodiments will be described in conjunction with the drawings. For the purpose of neatness of the drawings, some conventional structures and elements may be shown in a simple and schematic manner in the drawings. In addition, some features in the drawings may be slightly enlarged or their proportions or dimensions may be changed to achieve the purpose of facilitating understanding and viewing of the technical features of the present invention, but this is not intended to limit the present invention. In addition, some of the structural lines in some of the drawings may be represented by dashed lines for ease of viewing.

In addition, hereinafter, terms such as "end", "portion", "portion", "region", "location" may be used to describe specific elements and structures or specific technical features on or between them, but these elements AND structures are not limited by these terms. Terms such as "substantially", "about" and "substantially" may also be used hereinafter to describe a reasonable or acceptable amount of deviation that may exist from the circumstances or events modified and still achieve the desired result .

In addition, hereinafter, "at least one" may be used to describe the quantity of a referenced element, but unless expressly stated otherwise, it should not be limited to the case where the quantity is "only one". The term "and/or" may also be used below, which should be understood to include any and all combinations of one or more of the listed items.

Referring to FIG. 1 , an embodiment of the present invention provides a flywheel energy storage system 1 , which may also be referred to as a “system” hereinafter. In general, the flywheel energy storage system 1 may include a flywheel module 10 and a drive module 20 . The flywheel module 10 is mainly a part of the flywheel energy storage system 1 for receiving kinetic energy to store energy, and the drive module 20 may Assembled on the flywheel module 10 refers to the part of the flywheel energy storage system 1 for providing kinetic energy.

Specifically, the flywheel module 10 may include a casing 110 , a shaft 150 and a flywheel 130 . The casing 110 can surround a closed space and be evacuated to form a vacuum chamber S, but the present invention is not limited to the shape of the casing 110 and the means of evacuating. The housing 110 may be made of, for example, an aluminum alloy or other material with high rigidity but non-magnetic conductivity, but the present embodiment is not limited to the material of the housing 110 . In addition, the housing 110 is not limited to be an integrally formed structure, or may be assembled into a single piece from a multi-section structure. In the case where the housing 110 is assembled in a multi-segment structure, the segments can be connected by bolts, and the joints of the segments can be lined or coated with sealant to achieve an airtight effect.

Looking further, in this embodiment, the housing 110 may include two parts, which are a flywheel accommodating part 111 and an extending isolation part 113 respectively. The extension isolation portion 113 axially extends from one side of the flywheel accommodating portion 111 . The flywheel accommodating portion 111 and the extension isolation portion 113 are slightly cylindrical, but the diameter of the flywheel accommodating portion 111 is larger than that of the extending isolation portion 113 . The flywheel accommodating portion 111 and the extending isolation portion 113 can be assembled in any suitable manner, and their inner spaces are connected to form the aforementioned vacuum chamber S together. In addition, it is defined herein that the housing 110 may have an inner wall surface 114 and an outer wall surface 115. As shown in the figure, the inner wall surface 114 refers to the space on the flywheel accommodating portion 111 and the extending isolation portion 113 for forming the vacuum chamber S around them. and the outer wall surface 115 refers to the outer surface opposite to the inner wall surface 114 and facing outward.

The rotating shaft 130 is accommodated in the vacuum chamber S of the housing 110 . As shown in the figure, part of the rotating shaft 130 is accommodated in the flywheel accommodating part 111 , and another part of the rotating shaft 130 is accommodated in the extending isolation part 113 . The flywheel 150 is also accommodated in the vacuum chamber S of the housing 110 . As shown in the figure, the flywheel 150 is accommodated in the flywheel accommodating portion 111 , and the rotating shaft 130 passes through the flywheel 150 and is fixed with the flywheel 150 , thereby forming a rotating body together with the flywheel 150 . In this configuration, the rotating shaft 130 can receive the kinetic energy of the driving module 20 to rotate, thereby driving the flywheel 150 to rotate in the vacuum chamber S together.

In addition, the flywheel 150 is used as a carrier for energy storage, and the higher the energy that can be stored per unit weight or unit volume, the better (ie, the energy density). To achieve this purpose, in this embodiment or other embodiments, the flywheel 150 The outer shape is roughly cylindrical, but the present invention is not limited to this, and the flywheels in other embodiments of the present invention can also have desired shapes according to various practical needs. On the other hand, the material of the flywheel 150 can be made of a material with high structural strength and high density, so as to help improve the rotating quality per unit volume and avoid the problem of accidental rupture when a huge centrifugal force is generated during rotation. Not limited to this.

In addition, in this embodiment, the flywheel energy storage system 1 may further include two passive magnetic bearings (PMB) 190 , and the passive magnetic bearings 190 may be disposed at opposite ends of the rotating shaft 130 respectively. Specifically, one of the passive magnetic bearings 190 can be disposed on one end of the rotating shaft 130 located in the flywheel accommodating portion 111 , and the other passive magnetic bearing 190 can be disposed on one end of the rotating shaft 130 located in the extending isolation portion 113 . place. The passive magnetic bearing 190 is mainly used to provide support for the rotating shaft 130 in the axial direction.

In detail, the passive magnetic bearings 190 each include a permanent magnet group 191 and a permanent magnet group 193 , the permanent magnet group 191 is located in the vacuum chamber S and is fixed on the rotating shaft 130 , and the permanent magnet group 193 is located outside the vacuum chamber S And it is fixed on the outer wall surface 115 of the extending isolation portion 113 and surrounds the permanent magnet group 191 . More specifically, the permanent magnet group 193 is circumferentially arranged on the extending spacer 113 . The permanent magnet group 191 and the permanent magnet group 193 may be continuous annular structures or formed of a plurality of subunits spaced apart, and the present invention is not limited thereto. The positions of the permanent magnet groups 191 and 193 correspond to each other, and each has a plurality of permanent magnet arrangements that can interact with the other, so as to provide a magnetic buoyancy force in the axial direction to the rotating shaft 130 , so that the rotating shaft 130 and the flywheel 150 can be energized. It is suspended in the vacuum chamber S to avoid friction with surrounding structures when the rotating shaft 130 and the flywheel 150 rotate. It can be seen from this that the passive magnetic bearing 190 can be regarded as a passive axial magnetic bearing. In some cases, when the permanent magnets of the permanent magnet sets 191 and 193 are properly arranged and spaced, a magnetic buoyancy force of at least about 900 to 1100 Newtons can be generated to help the rotating shaft 130 and the flywheel 150 resist gravity. However, it should be stated that, as long as the support of the rotating shaft 130 and the flywheel 150 in the desired direction can be achieved, the permanent magnets interacting on the permanent magnet groups 191 and 193 can be arranged in any known suitable manner, and the number and specifications of the permanent magnets can also be adjusted. Adjustment is made according to actual needs, and the present invention is not limited to this.

It should be added that the passive magnetic bearing 190 is only composed of permanent magnets, so no significant heat energy will be generated when the magnetic levitation force is generated by the interaction. Of course, based on other practical considerations, the number of passive magnetic bearings can be selectively increased or decreased in the flywheel module of other embodiments, and the present invention is not limited thereto.

In addition, in this embodiment, the flywheel energy storage system 1 may further include an auxiliary bearing 195 , and the auxiliary bearing 195 may be located in the extending isolation portion 113 to support an outer flange 131 of the rotating shaft 130 . The ring portion 131 is an annular structure radially protruding from the surface of the rotation shaft 130 . The auxiliary bearing 195 can support the outer ring portion 131 to provide radial positioning and axial support to the rotating shaft 130 , whereby the auxiliary bearing 195 can also be used to prevent problems such as overload or failure of the magnetic bearing in the system. However, the outer ring portion 131 and the auxiliary bearing 195 are optional, and the present invention is not limited thereto.

On the other hand, the driving module 20 is a device that uses magnetic coupling instead of mechanical connection to transmit torque, so the rotating shaft 130 and the flywheel 150 can be driven outside the vacuum chamber S of the flywheel module 10 . As shown in the figure, the driving module 20 may include a mounting base 205 , an inner rotor 211 , an outer rotor 213 and a stator 230 .

In detail, the mounting base 205 can be fixed on the housing 110 , for example, sleeved outside the extending isolation portion 113 of the housing 110 , and can be fixed on the extending isolating portion 113 and the flywheel accommodating portion 111 in any suitable manner, for example, it can be Not limited to screw locking or welding.

The inner rotor 211 is located in the extending isolation portion 113 of the housing 110 , and the inner rotor 211 is sleeved on the rotating shaft 130 and fixed to the rotating shaft 130 . In other words, the inner rotor 211 is located in the vacuum chamber S and is fixed to the part of the rotating shaft 130 located in the extended isolation portion 113 . Therefore, the inner rotor 211 can be integrally formed with the rotating shaft 130 and the flywheel 150 to rotate in the vacuum chamber S together. In addition, in order to rotate in the vacuum chamber S without interfering with the inner wall surface 114 of the extended isolation portion 113 , an appropriate gap can be maintained between the inner rotor 211 and the extended isolation portion 113 . The inner rotor 211 can include an inner rotor magnet base 2111 for setting and fixing a plurality of suitable permanent magnets 2112. The inner rotor magnet base 2111 can be made of suitable material or structure (such as silicon steel sheet stacking) to support, These permanent magnets 2112 are protected and isolated, but the present invention is not limited to the quantity, shape, type, etc. of the permanent magnets in the inner rotor 211 .

The outer rotor 213 is disposed outside the extending isolation portion 113 and corresponds to the position of the inner rotor 211 . In other words, the outer rotor 213 is located outside the vacuum chamber S and surrounds the inner rotor 211 . Looking further, the outer rotor 213 can be movably disposed on the mounting seat 205 via the ball bearing 270 , and the outer rotor 213 surrounds the extended isolation portion 113 and maintains an air gap with the extended isolation portion 113 . The outer rotor 213 can include an outer rotor magnet base 2131 for setting and fixing a plurality of suitable permanent magnets 2132. The outer rotor magnet base 2131 can be made of suitable material or structure (such as silicon steel sheet stacking) to support, These permanent magnets 2132 are protected and isolated, but the present invention is not limited to the quantity, shape, type, etc. of the permanent magnets in the outer rotor 213 .

The stator 230 is fixed to the mounting seat 205 and is located outside the outer rotor 213 . In other words, the stator 230 is located outside the vacuum chamber S and surrounds the outer rotor 213 . The stator 230 may include a stator core and windings wound around the stator core, wherein, for the purpose of simplifying the drawing, the stator 230 is only represented by a simple block diagram without specifically depicting the stator core with windings.

A current can be applied to the windings of the stator 230 to generate a magnetic field on the stator iron core of the stator 230 and the silicon steel sheet of the outer rotor 213 to drive the outer rotor 213 to rotate. From this, it can be seen that the stator 230 and the outer rotor 213 can jointly form an electric motor EM. In this case, the stator 230 may be considered or referred to as the stator of the electric motor EM, and the outer rotor 213 may be considered or referred to as the inner rotor of the electric motor EM.

In addition, when the stator 230 drives the outer rotor 213 to rotate, the magnetic lines of force of the permanent magnets 2132 on the outer rotor 213 can pass through the extended isolation portion 113 and the gap to drive the inner rotor 211 , thereby making the inner rotor 211 together with the rotating shaft 130 and the flywheel 150 The assembled assembly rotates synchronously. From this, it can be seen that the inner rotor 211 and the outer rotor 213 can jointly form a magnetic coupler 210 , which drives the rotating shaft 130 and the flywheel 150 in the vacuum chamber S by means of magnetic transmission. It should be stated here that, as long as the purpose of synchronizing rotation between the inner rotor 211 and the outer rotor 213 through magnetic force can be achieved, the permanent magnet 2112 of the inner rotor 211 and the permanent magnet 2132 of the outer rotor 213 can be in any known suitable manner arranged, the present invention is not limited thereto.

In addition, in the present embodiment, the flywheel energy storage system 1 may further include at least one active magnetic bearing (AMB) 250 . It should be stated first that, for the sake of simplicity, the active magnetic bearing 250 Only the permanent magnet group 251 and the magnetic bearing stator portion 253 are shown, and other components that do not affect the understanding of the spirit of this embodiment, such as actuators, controllers, power amplifiers, etc., will be omitted and not shown.

For example, the active magnetic bearings 250 may be disposed on opposite sides of the motor EM, or the motor EM is bounded between the active magnetic bearings 250 . For one of the active magnetic bearings 250 , the magnetic bearing stator portion 253 has windings (not shown), and the permanent magnet set 251 may have an arrangement of several permanent magnets. The permanent magnet group 251 is located in the vacuum chamber S and fixed on the rotating shaft 130 . The magnetic bearing stator part 253 is located outside the vacuum chamber S and surrounds the permanent magnet group 251 . More specifically, the magnetic bearing stator portion 253 is circumferentially arranged in the extending spacer portion 113 . The permanent magnet group 251 and the magnetic bearing stator portion 253 may be continuous annular structures or may be composed of a plurality of subunits spaced apart, and the present invention is not limited thereto. In this configuration, current can be passed to the windings of the magnetic bearing stator portion 253 to generate a magnetic force acting on the permanent magnet group 251 , thereby generating a radial magnetic levitation force on the rotating shaft 130 to maintain the rotating shaft 130 at its predetermined rotation center line, and helps to stabilize or restrain the shaking of the rotating shaft 130 when the rotating shaft 130 rotates at a high speed. It can be seen from this that the active magnetic bearing 250 can be regarded as an active radial magnetic bearing. In addition, optionally, at least one of the magnetic bearing stator parts 253 may, for example, be directly attached to the outer wall surface 115 at the extension isolation part 113 and located outside the vacuum chamber S, in addition to helping to directly transfer the generated heat through the Conducted to the extension isolation portion 113 and excluded from the outside, also helps to shorten the distance between the magnetic levitation bearing stator portion 253 and the permanent magnet group 251 to achieve the required magnetic levitation force. In addition, it is added that as long as the active magnetic bearing 250 can provide the support of the rotating shaft 130 and the flywheel 150 in the desired direction, the present invention does not depend on the number, arrangement, specification, etc. of the active magnetic bearing 250 and the permanent magnets therein. limit.

To sum up, the flywheel energy storage system 1 utilizes the magnetic shaft coupling 210 to transmit the power of the motor EM to the rotating shaft 130 and the flywheel 150 in the vacuum chamber S without mechanical contact, and the rotating shaft 130 and the flywheel 150 It can also be suspended in the vacuum chamber S through the passive magnetic bearing 190 . Thereby, the rotating shaft 130 and the flywheel 150 can rotate in the vacuum chamber S in a non-contact and frictionless manner, which is not affected by the vibration of the motor EM, and also helps to maintain the air density of the vacuum chamber S.

Moreover, it is worth noting that although the stator 230 of the motor EM will generate high temperature during operation due to the passing of current, the stator 230 is isolated from the vacuum chamber S, so the heat energy generated by the stator 230 will not affect the vacuum chamber. The rotating shaft 130 and the flywheel 150 in the S will not affect the permanent magnets in the passive magnetic bearing 190 . Also, for the same reason, the stator 230 can be cooled by a cooling method outside the vacuum chamber S, which can avoid the traditional heat dissipation method of inserting an air-cooled or liquid-cooled tube into the casing, thereby greatly reducing the difficulty of dissipating heat to the motor stator.

In addition, the inner rotor of the motor EM (ie the outer rotor 213 ) is also located outside the vacuum chamber S, that is, the motor EM is completely isolated from the vacuum chamber S, so there is a gap between the stator 230 and the outer rotor 213 The air gap can be maintained within a required range, so that the stator 230 of the motor EM can make the inner rotor (ie, the outer rotor 213 ) reach the required rotational speed with a suitable current.

On the other hand, although the magnetic bearing stator part 253 of the active magnetic bearing 250 is also high temperature due to the current flow, the magnetic bearing stator part 253 is isolated from the vacuum chamber S, so the heat energy generated by the magnetic bearing stator part 253 will not be generated. It affects the rotating shaft 130 in the vacuum chamber S, the flywheel 150 and the permanent magnets in the passive magnetic bearing 190 .

From this, it can be seen that the flywheel energy storage system 1 of the present embodiment can store all the components that generate thermal energy (such as the stator 211 of the motor EM and the magnetic bearing stator part 253 ) to the electric motor EM and the active magnetic bearing 250 Being isolated from the vacuum chamber S, the vacuum chamber S becomes a heat-free environment and has no requirement for heat dissipation, so as to avoid using traditional heat dissipation means that would affect the vacuum tightness.

The foregoing is only one exemplary embodiment of the present invention, and is not intended to limit the present invention. Those with ordinary knowledge in the relevant field can make appropriate and reasonable adjustments based on the content taught by the foregoing embodiments. For example, please refer to FIG. 2 , which is a schematic plan view of a flywheel energy storage system 1 ′ according to another embodiment of the present invention, since the difference between the flywheel energy storage system 1 ′ of this embodiment and the flywheel energy storage system 1 of FIG. 1 is only It is the part of the motor EM', therefore, the following paragraphs only describe the differences of the embodiments, and the similar or identical parts can be understood by referring to the above-mentioned relevant paragraphs and will not be repeated.

As shown in the figure, in the motor EM' of the flywheel energy storage system 1', at least one passive magnetic bearing 197 is provided between the stator 230' and the outer rotor 213' (ie, the inner rotor of the motor EM'). Each of the passive magnetic bearings 197 includes a permanent magnet set 1971 and a permanent magnet set 1973 . The permanent magnet group 1971 is fixed on the outer wall surface of the outer rotor 213' facing the stator 230', and the permanent magnet group 1973 is fixed on the outer wall surface of the stator 230' facing the outer rotor 213', and surrounds the permanent magnet group 1971 and the outer rotor 213' . Similar or identical to the passive magnetic bearing 190 of the previous embodiment, the permanent magnet sets 1971 and 1973 of the passive magnetic bearing 197 have corresponding positions, and each has a plurality of permanent magnet arrangements capable of interacting with the other, so as to provide The magnetic buoyancy force in the axial direction can act on the outer rotor 213 ′, which can greatly reduce the gravitational load generated by the outer rotor 213 ′ on the ball bearing 270 . In this way, the frictional force generated by the contact bearing during rotation can be greatly reduced, which not only helps to reduce the loss of the ball bearing 270 to increase the service life, but also helps to reduce the frictional loss of transmitting kinetic energy and helps to improve the overall efficacy.

It is added that, in some cases, the permanent magnets of the permanent magnet sets 1971 and 1973 can generate at least about 900 to 1100 N of magnetic buoyancy force to help the outer rotor 213' resist gravity under proper arrangement and spacing configuration. It should be noted that, as long as the outer rotor 213' can be supported in the desired direction, the permanent magnets interacting with the permanent magnet groups 1971 and 1973 can be arranged in any known suitable manner, and the number and specifications of the permanent magnets can also be arranged according to The present invention is not limited to this.

Of course, based on some practical requirements, the magnetic bearing stator part of at least one of the active magnetic bearing can be selectively placed in the vacuum chamber. For example, referring to FIG. 3 , the difference between the flywheel energy system 1 ″ of an embodiment of the present invention and the flywheel energy system of the previous embodiment may only be that the magnetic bearing stator portion 253 of the active magnetic bearing 250 ′ can be modified In order to be placed in the vacuum chamber S, more specifically, the magnetic bearing stator portion 253 may be located in the vacuum chamber S by, for example, being attached to the inner wall surface 114 of the extending isolation portion 113 .

In this configuration, the magnetic bearing stator portion 253 and the permanent magnet group 251 of the active magnetic bearing 250 ′ are both located in the vacuum chamber S, so there is no extended isolation portion between the magnetic bearing stator portion 253 and the permanent magnet group 251 . 113 is made of solid material and the distance between them is shortened, which helps to further enhance the magnetic effect of the magnetic bearing stator part 253 on the permanent magnet group 251, thereby helping to improve the active magnetic bearing 250' to the rotating shaft. 130 generated radial magnetic levitation. In other words, with the configuration of the active magnetic bearing 250', the vibration generated when the rotating shaft 130 rotates at a high speed can be further suppressed, thereby ensuring that the rotating shaft 130 rotates on the predetermined rotation centerline. It should be noted here that, since the magnetic bearing stator portion 253 is directly attached to the inner wall surface 114 of the extension isolation portion 113 , the thermal energy generated by the magnetic bearing stator portion 253 during operation can be directly conducted to the extension isolation portion 113 . discharged out.

Alternatively, based on some requirements, one of the active magnetic bearings can be selectively placed at one end of the rotating shaft, or an additional active magnetic bearing can be placed at one end of the rotating shaft. For example, referring to FIG. 4 , the difference between the flywheel energy system 1 ″' of an embodiment of the present invention and the flywheel energy system of the previous embodiment may only be that a set of active magnetic bearing 250 is placed in the The rotating shaft 130 extends from one end of the isolation portion 113 , so as to be disposed in the flywheel accommodating portion 111 instead.

The area in the flywheel accommodating portion 111 for arranging the active magnetic bearing 250 is relatively abundant, which helps the active magnetic bearing 250 to be further adjusted according to requirements such as size or specification. Moreover, under this configuration, the control of the active magnetic bearing 250 can be directly performed on the opposite ends of the rotating shaft 130 , and since one of the active magnetic bearing 250 is disposed in the area of the rotating shaft 130 that is closer to the flywheel 150 , the The opposite sides of the flywheel 150 in the axial direction can receive the radial magnetic levitation force of the active magnetic bearing 250 via the rotating shaft 130 , thereby helping to further reduce the influence of the flywheel 150 on the rotational stability of the whole moving member. In addition, optionally, the magnetic bearing stator portion 253 of the active magnetic bearing 250 can be directly attached to the inner wall surface 114 of the flywheel accommodating portion 111 , or directly embedded in the solid portion of the flywheel accommodating portion 111 . , so that the heat energy generated by the magnetic bearing stator portion 253 during operation can be directly conducted to the flywheel accommodating portion 111 and discharged to the outside.

To sum up, in the flywheel energy storage system disclosed in the embodiments of the present invention, since the rotor of the electric motor simultaneously acts as the outer rotor of the magnetic coupling to drive the inner rotor fixed to the rotating shaft in the vacuum chamber, it is possible to realize the mechanical contactless system. The shaft and the flywheel are driven in such a way that the shaft and the flywheel can rotate without resistance.

In addition, the stator of the electric motor that generates heat through current is excluded from the vacuum chamber. This configuration enables the flywheel energy storage system to isolate the components that mainly generate heat energy during operation from the vacuum chamber, so that the flywheel energy storage system can avoid the use of Heat dissipation, which traditionally affects vacuum tightness, helps ensure the air tightness required for flywheel operation.

Optionally, the magnetic bearing stator part of the active magnetic bearing can also be excluded from the vacuum chamber together. In this case, the stator of the motor of the flywheel energy storage system and the magnetic bearing stator part of the active magnetic bearing All are located outside the vacuum chamber, so that the flywheel energy storage system can use the motor and the active magnetic bearing at the same time. The environment of the heat source without the need for heat dissipation.

Of course, in order to further improve the radial magnetic levitation force of the active magnetic bearing on the rotating shaft and other practical requirements, the magnetic bearing stator part of the active magnetic bearing can also be arranged in the vacuum chamber to avoid the magnetic bearing stator part of the active magnetic bearing and the magnetic levitation bearing. Solid materials exist between groups of permanent magnets. And under this configuration, by directly adhering the magnetic bearing stator portion 253 of the active magnetic bearing 250' to the inner wall surface of the housing, the thermal energy generated by the magnetic bearing stator portion can be directly conducted and discharged to the outside, Therefore, the influence of thermal energy on the operation can be avoided while achieving the effect of improving the radial magnetic levitation.

In addition, in the flywheel energy system of the embodiment of the present invention, a passive magnetic bearing can be selectively disposed at the moving element, for example, at one end of the rotating shaft, opposite ends or at any desired position, or at the motor between the stator and the rotor, so as to provide a magnetic levitation force in a specific direction to the applied moving parts, so as to help stabilize the rotational motion of the moving parts and reduce frictional resistance, and also help reduce the load generated by the moving parts on the contact bearing. , so that the kinetic energy can be transmitted and lost, and the service life of the bearing can be extended.

Although the present invention is disclosed in the foregoing embodiments, it is not intended to limit the present invention. Changes and modifications made without departing from the spirit and scope of the present invention belong to the scope of patent protection of the present invention. For the protection scope defined by the present invention, please refer to the attached patent application scope.

1, 1’, 1’’, 1’’’: Flywheel energy storage system 10: Flywheel module 20: Driver module 110: Shell 111: Flywheel accommodating part 113: Extension Separator 114: inner wall surface 115: Outer wall 130: Spindle 131: Outer Ring Department 150: Flywheel 190: Passive Magnetic Bearings 191, 193, 251, 1971, 1973: Permanent Magnet Sets 195: Auxiliary bearing 197: Passive Magnetic Bearings 205: Mounting Seat 210, 210’: Magnetic coupling 211, 211’: inner rotor 213, 213’: outer rotor 230, 230’: stator 250, 250’: Active Magnetic Bearings 253: Magnetic bearing stator part 270: Ball bearing 2111: Inner rotor magnet holder 2112, 2132: Permanent Magnets 2131: Outer rotor magnet holder EM, EM': Motor S: Vacuum chamber

FIG. 1 is a schematic plan view of a flywheel energy storage system according to an embodiment of the present invention. 2 is a schematic plan view of a flywheel energy storage system according to another embodiment of the present invention. 3 is a schematic plan view of a flywheel energy storage system according to yet another embodiment of the present invention. 4 is a schematic plan view of a flywheel energy storage system according to still another embodiment of the present invention.

1: Flywheel energy storage system

10: Flywheel module

20: Driver module

110: Shell

111: Flywheel accommodating part

113: Extension Separator

130: Spindle

131: Outer Ring Department

150: Flywheel

190: Passive Magnetic Bearings

191, 193, 251: Permanent Magnet Sets

195: Auxiliary bearing

205: Mounting Seat

210: Magnetic coupling

211: inner rotor

213: Outer rotor

230: Stator

250: Active Magnetic Bearing

253: Magnetic bearing stator part

270: Ball bearing

2111: Inner rotor magnet holder

2112, 2132: Permanent Magnets

2131: Outer rotor magnet holder

EM: electric motor

S: Vacuum chamber

Claims (13)

A flywheel energy storage system, comprising: a shell with a vacuum chamber; a flywheel, set in the vacuum chamber; a rotating shaft, set in the vacuum chamber and passing through the flywheel; an inner rotor, set in the vacuum The chamber is fixed on the rotating shaft; an outer rotor is arranged outside the vacuum chamber, the outer rotor surrounds the inner rotor and can magnetically act on the inner rotor; and a stator is arranged outside the vacuum chamber , the stator surrounds the outer rotor and can be used to drive the outer rotor. The flywheel energy storage system according to claim 1, further comprising at least one active magnetic bearing, including a magnetic bearing stator part and a permanent magnet group, the permanent magnet group is located in the vacuum chamber and fixed on the rotating shaft, the The magnetic bearing stator portion is located outside the vacuum chamber and surrounds the permanent magnet group. The flywheel energy storage system according to claim 1, further comprising at least one active magnetic bearing, including a magnetic bearing stator part and a permanent magnet group, the permanent magnet group is located in the vacuum chamber and fixed on the rotating shaft, the A magnetic bearing stator portion is located within the vacuum chamber and surrounds the permanent magnet group. The flywheel energy storage system of claim 3, wherein the magnetic bearing stator portion of the at least one active magnetic bearing is directly attached to an inner wall surface of the housing. The flywheel energy storage system according to any one of claims 2 or 3, wherein the housing comprises a flywheel accommodating portion and an extended isolation portion connected to each other, the flywheel accommodating portion and The extended isolation parts communicate with each other to surround the vacuum chamber together, the flywheel is located in the flywheel accommodating part, the rotating shaft extends from the flywheel accommodating part to the extended isolation part, the inner rotor and the at least one active type The permanent magnet groups of the magnetic suspension bearing are all located in the extended isolation portion. The flywheel energy storage system of claim 5, wherein the stator, the outer rotor and the inner rotor are all located in the extended isolation portion. The flywheel energy storage system of claim 5, wherein the outer rotor surrounds the extended isolation portion, and the magnetic bearing stator portion of the at least one active magnetic bearing is circumferentially disposed on the extended isolation portion. The flywheel energy storage system according to any one of claims 2 or 3, wherein the number of the at least one active magnetic bearing is two, which are respectively disposed on opposite sides of a motor formed by the stator and the outer rotor. The flywheel energy storage system according to any one of claims 2 or 3, wherein the number of the at least one active magnetic bearing is two, which are respectively disposed on a side of the flywheel relatively far away from the inner rotor and the inner rotor relatively far away from the inner rotor. one side of the flywheel. The flywheel energy storage system of claim 1, further comprising an auxiliary bearing located in the vacuum chamber, wherein the rotating shaft has an outer ring portion radially protruding from the surface of the rotating shaft, and the auxiliary bearing passes through the outer ring portion Axial support is provided for the shaft. The flywheel energy storage system of claim 1, further comprising at least one passive magnetic bearing, the at least one passive magnetic bearing comprising two permanent magnet sets corresponding to each other, one of the permanent magnet sets of the at least one passive magnetic bearing is located at The vacuum chamber is fixed on the rotating shaft, and the other permanent magnet group of the at least one passive magnetic bearing is located outside the vacuum chamber. The flywheel energy storage system according to claim 11, wherein the number of the at least one passive magnetic bearing is two, which are respectively disposed at opposite ends of the rotating shaft. The flywheel energy storage system of claim 1, further comprising at least one passive magnetic bearing, the at least one passive magnetic bearing comprising two permanent magnet sets corresponding to each other, one of the permanent magnet sets of the at least one passive magnetic bearing is fixed On the outer wall surface of the outer rotor facing the stator, the other permanent magnet group of the at least one passive magnetic bearing is fixed on the outer wall surface of the stator facing the outer rotor and surrounds the outer rotor.

Images