CA2327492C - Magnetically suspended flywheel system - Google Patents
Magnetically suspended flywheel system Download PDFInfo
- Publication number
- CA2327492C CA2327492C CA2327492A CA2327492A CA2327492C CA 2327492 C CA2327492 C CA 2327492C CA 2327492 A CA2327492 A CA 2327492A CA 2327492 A CA2327492 A CA 2327492A CA 2327492 C CA2327492 C CA 2327492C
- Authority
- CA
- Canada
- Prior art keywords
- shaped
- magnet
- assembly
- ring
- rotor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C39/00—Relieving load on bearings
- F16C39/06—Relieving load on bearings using magnetic means
- F16C39/063—Permanent magnets
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K7/00—Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
- H02K7/02—Additional mass for increasing inertia, e.g. flywheels
- H02K7/025—Additional mass for increasing inertia, e.g. flywheels for power storage
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02N—ELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
- H02N15/00—Holding or levitation devices using magnetic attraction or repulsion, not otherwise provided for
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C2361/00—Apparatus or articles in engineering in general
- F16C2361/55—Flywheel systems
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/16—Mechanical energy storage, e.g. flywheels or pressurised fluids
Abstract
A magnetically suspended flywheel system comprises a housing, a stator assembly, and a rotor assembly. The stator assembly comprises a ring-shaped stator magnet having a substantially triangular cross section. The rotor assembly comprises a vertical shaft, a cone-shaped rotor magnet having a substantially triangular cross section, and a flywheel. The ring-shaped stator magnet has the same sense of magnetisation as the cone-shaped rotor magnet. The ring-shaped stator magnet forms inverse heart-shaped magnetic flux lines, and the cone-shaped rotor magnet forms heart-shaped magnetic flux lines. An upward magnetic repulsion force between the inverse heart-shaped magnetic flux lines of the ring-shaped stator magnet and the heart-shaped magnetic flux lines of the cone-shaped rotor magnet equals a downward gravitational force by the rotor assembly in order to passively suspend the rotor assembly so that the rotor assembly is capable of rotating around the central axis of rotation. This invention relates to flywheel systems, and the principal use of the invention is for kinetic energy storage systems.
Description
Description Title = Magnetically Suspended Flywheel System Technical Field = This invention relates to flywheel systems, more particularly to a magnetic flywheel system.
Background Art = There are many instances where it would be desirable to be able to use a magnetic force in order to suspend a flywheel for a low-friction operation.
= A number of patents disclose flywheel systems having active magnetic suspension systems, or superconducting magnetic bearings comprising low-temperature superconductors or high-temperature superconductors using Meissner effect, in order to circumvent Earnshaw's Theorem and to levitate a flywheel with static stability.
= Canadian Patent 2 190 298 discloses "Magnetically Levitated Axleless Wheel System". This prior art has a magnetically levitated wheel made of permanent magnets, but it does not have a flywheel for kinetic energy storage.
= U.S. Patent 4 382 245 discloses "Levitation device", or Levitron (Trade Mark). This prior art has a dish-shaped permanent magnet in one form with an upper surface of a first polarity and a lower surface of a second polarity disposed in co-axial relationship to a second magnet having the opposite polar relationships.
= U.S. Patent 5 495 221 discloses "Dynamically stable magnetic suspension/bearing system". This prior art contains magnetic subsystems which act together to support a rotating element in a state of dynamic equilibrium.
= U.S. Patent 5 760 506 discloses "Flywheels for energy storage". This prior art has a bearing assembly including a bulk high temperature superconductive magnet that provides lateral stability to the flywheel.
= These prior art arrangements do not have a passive magnetic suspension system which operates at room temperature, and uses permanent magnets to form a cone-shaped well in a toroidal magnetic field.
Description of the Invention = It is a primary object of the invention to provide a flywheel system which has a passive magnetic suspension system.
= It is another object of the invention to provide a flywheel system which operates at room temperature.
= It is another object of the invention to provide a flywheel system which uses permanent magnets in order to form a cone-shaped well in a toroidal magnetic field.
= A magnetically suspended flywheel system comprises a housing, a stator assembly, and a rotor assembly. The stator assembly comprises a ring-shaped stator magnet having a substantially triangular cross section. The rotor assembly comprises a vertical shaft, a cone-shaped rotor magnet having a substantially triangular cross section, and a flywheel. The ring-shaped stator magnet has the same sense of magnetisation as the cone-shaped rotor magnet. The ring-shaped stator magnet forms inverse heart-shaped magnetic flux lines, and the cone-shaped rotor magnet forms heart-shaped magnetic flux lines. An upward magnetic repulsion force between the inverse heart-shaped magnetic flux lines of the ring-shaped stator magnet and the heart-shaped magnetic flux lines of the cone-shaped rotor magnet equals a downward gravitational force by the rotor assembly in order to passively suspend the rotor assembly so that the rotor assembly is capable of rotating around the central axis of rotation.
Brief Description of the Figures in the Drawings = In drawings which illustrate embodiments of the invention:
o Figure 1 marked "Prior Art" is a sectional side view of a conventional magnetically suspended flywheel system;
o Figure 2 marked "Prior Art" is a sectional top view of a conventional magnetically suspended flywheel system;
o Figure 3 marked "Prior Art" is a schematic diagram of a conventional magnetically suspended flywheel system;
o Figure 4 is a sectional side view of one embodiment of a magnetically suspended flywheel system according to the invention;
o Figure 5 is a sectional top view of one embodiment of a magnetically suspended flywheel system according to the invention;
o Figure 6 is a schematic diagram of one embodiment of a magnetically suspended flywheel system according to the invention;
o Figure 7 is a sectional side view of another embodiment of a magnetically suspended flywheel system according to the invention;
o Figure 8 is a sectional top view of another embodiment of a magnetically suspended flywheel system according to the invention;
and o Figure 9 is a schematic diagram of another embodiment of a magnetically suspended flywheel system according to the invention.
Modes for Carrying Out the Invention = One conventional flywheel system shown in Figure 1 in sectional side view marked "Prior Art" and Figure 2 in sectional top view marked "Prior Art"
comprises a housing 1-0, a stator assembly, and a rotor assembly.
= The stator assembly comprises a ring-shaped stator magnet 1-1, securely attached to the housing 1-0.
Background Art = There are many instances where it would be desirable to be able to use a magnetic force in order to suspend a flywheel for a low-friction operation.
= A number of patents disclose flywheel systems having active magnetic suspension systems, or superconducting magnetic bearings comprising low-temperature superconductors or high-temperature superconductors using Meissner effect, in order to circumvent Earnshaw's Theorem and to levitate a flywheel with static stability.
= Canadian Patent 2 190 298 discloses "Magnetically Levitated Axleless Wheel System". This prior art has a magnetically levitated wheel made of permanent magnets, but it does not have a flywheel for kinetic energy storage.
= U.S. Patent 4 382 245 discloses "Levitation device", or Levitron (Trade Mark). This prior art has a dish-shaped permanent magnet in one form with an upper surface of a first polarity and a lower surface of a second polarity disposed in co-axial relationship to a second magnet having the opposite polar relationships.
= U.S. Patent 5 495 221 discloses "Dynamically stable magnetic suspension/bearing system". This prior art contains magnetic subsystems which act together to support a rotating element in a state of dynamic equilibrium.
= U.S. Patent 5 760 506 discloses "Flywheels for energy storage". This prior art has a bearing assembly including a bulk high temperature superconductive magnet that provides lateral stability to the flywheel.
= These prior art arrangements do not have a passive magnetic suspension system which operates at room temperature, and uses permanent magnets to form a cone-shaped well in a toroidal magnetic field.
Description of the Invention = It is a primary object of the invention to provide a flywheel system which has a passive magnetic suspension system.
= It is another object of the invention to provide a flywheel system which operates at room temperature.
= It is another object of the invention to provide a flywheel system which uses permanent magnets in order to form a cone-shaped well in a toroidal magnetic field.
= A magnetically suspended flywheel system comprises a housing, a stator assembly, and a rotor assembly. The stator assembly comprises a ring-shaped stator magnet having a substantially triangular cross section. The rotor assembly comprises a vertical shaft, a cone-shaped rotor magnet having a substantially triangular cross section, and a flywheel. The ring-shaped stator magnet has the same sense of magnetisation as the cone-shaped rotor magnet. The ring-shaped stator magnet forms inverse heart-shaped magnetic flux lines, and the cone-shaped rotor magnet forms heart-shaped magnetic flux lines. An upward magnetic repulsion force between the inverse heart-shaped magnetic flux lines of the ring-shaped stator magnet and the heart-shaped magnetic flux lines of the cone-shaped rotor magnet equals a downward gravitational force by the rotor assembly in order to passively suspend the rotor assembly so that the rotor assembly is capable of rotating around the central axis of rotation.
Brief Description of the Figures in the Drawings = In drawings which illustrate embodiments of the invention:
o Figure 1 marked "Prior Art" is a sectional side view of a conventional magnetically suspended flywheel system;
o Figure 2 marked "Prior Art" is a sectional top view of a conventional magnetically suspended flywheel system;
o Figure 3 marked "Prior Art" is a schematic diagram of a conventional magnetically suspended flywheel system;
o Figure 4 is a sectional side view of one embodiment of a magnetically suspended flywheel system according to the invention;
o Figure 5 is a sectional top view of one embodiment of a magnetically suspended flywheel system according to the invention;
o Figure 6 is a schematic diagram of one embodiment of a magnetically suspended flywheel system according to the invention;
o Figure 7 is a sectional side view of another embodiment of a magnetically suspended flywheel system according to the invention;
o Figure 8 is a sectional top view of another embodiment of a magnetically suspended flywheel system according to the invention;
and o Figure 9 is a schematic diagram of another embodiment of a magnetically suspended flywheel system according to the invention.
Modes for Carrying Out the Invention = One conventional flywheel system shown in Figure 1 in sectional side view marked "Prior Art" and Figure 2 in sectional top view marked "Prior Art"
comprises a housing 1-0, a stator assembly, and a rotor assembly.
= The stator assembly comprises a ring-shaped stator magnet 1-1, securely attached to the housing 1-0.
= The rotor assembly has a central axis of rotation, and is co-axially placed relative to the stator assembly. The rotor assembly comprises a vertical shaft 1-2 made of a non-magnetic material, a disc-shaped rotor magnet 1-3, and a flywheel 1-4 made of a ferromagnetic material such as iron (Fe), cobalt (Co) or nickel (Ni) so that the rotor assembly can be set in motion by an external prime mover magnetically coupled to the flywheel. The vertical shaft 1-2 has a top portion and a bottom portion.
The disc-shaped rotor magnet 1-3 is securely attached to the top portion of the vertical shaft 1-2. The flywheel 1-4 is securely attached to the bottom portion of the vertical shaft 1-2.
= The ring-shaped stator magnet 1-1 has the opposite sense of magnetisation to the disc-shaped rotor magnet 1-3. The ring-shaped stator magnet 1-1 forms magnetic flux lines, and the disc-shaped rotor magnet 1-3 forms magnetic flux lines. An upward magnetic repulsion force (Fm) between the magnetic flux lines of the ring-shaped stator magnet 1-1 and the magnetic flux lines of the disc-shaped rotor magnet 1-3 equal a downward gravitational force (Fg) by the rotor assembly in order to passively suspend the rotor assembly so that the rotor assembly is capable of rotating around the central axis of rotation, as shown in the schematic diagram of Figure 3 marked "Prior Art".
= Magnetic flux lines flowing in a same direction indicate a stable pattern, while magnetic flux lines flowing in opposite directions indicate an unstable pattern. The unstable magnetic flux line patterns at the air gap between the ring-shaped stator magnet 1-1 and the disc-shaped rotor magnet 1-3 in Figure 3 provide axial stability and radial instability. Although the diameter of the ring-shaped stator magnet 1-1 is different from the diameter of the disc-shaped rotor magnet 1-3, an eddy-current stabiliser 1-5 is required in order to overcome the radial instability. The gravitational force is used to suppress "tilt" and "whirl" instabilities.
= In one embodiment of the invention shown in Figure 4 in sectional side view and Figure 5 in sectional top view, a flywheel system comprises a housing 2-0, a stator assembly, and a rotor assembly.
= The stator assembly comprises a ring-shaped stator magnet 2-1 having a substantially triangular cross section, securely attached to the housing 2-0.
= The rotor assembly has a central axis of rotation, and is co-axially placed relative to the stator assembly. The rotor assembly comprises a vertical shaft 2-2 made of a non-magnetic material, a cone-shaped rotor magnet 2-3 having a substantially triangular cross section, and a flywheel 2-4 made of a non-magnetic material. The vertical shaft 2-2 has a top portion and a bottom portion. The cone-shaped rotor magnet 2-3 is securely attached to the top portion of the vertical shaft 2-2. The flywheel 2-4 is securely attached to the bottom portion of the vertical shaft 2-2.
= Unlike the conventional flywheel system, the ring-shaped stator magnet 2-1 has the same sense of magnetisation as the cone-shaped rotor magnet 2-3. The ring-shaped stator magnet 2-1 forms inverse heart-shaped magnetic flux lines, and the cone-shaped rotor magnet 2-3 forms heart-shaped magnetic flux lines. An upward magnetic repulsion force (Fm) between the inverse heart-shaped magnetic flux lines of the ring-shaped stator magnet 2-1 and the heart-shaped magnetic flux lines of the cone-shaped rotor magnet 2-3 equals a downward gravitational force (Fg) by the rotor assembly in order to passively suspend the rotor assembly so that the rotor assembly is capable of rotating around the central axis of rotation, as shown in the schematic diagram of Figure 6.
= Magnetic flux lines flowing in a same direction indicate a stable pattern, while magnetic flux lines flowing in opposite directions indicate an unstable pattern. The stable magnetic flux line patterns at the air gap between the ring-shaped stator magnet 2-1 and the cone-shaped rotor magnet 2-3 in Figure 6 provide axial stability and radial stability. These stabilities are due to a cone-shaped well in a toroidal magnetic field, which is formed by a concentrated first magnetic pole and a distributed second magnetic pole. The stable force field counters any overturning tendencies of the magnets. The gravitational force is used to suppress "tilt" and "whirl" instabilities.
= The equilibrium in this configuration is analogous to the Lagrange Points between gravitational bodies in space.
= Preferably, the ring-shaped stator magnet 2-1 of the stator assembly and the cone-shaped rotor magnet 2-3 of the rotor assembly are made of rare-earth permanent magnet, which is an electrical insulator so that eddy current is not induced during operation.
= The ring-shaped stator magnet 2-1 of the stator assembly may consist of a plurality of ring-shaped magnets having different diameters, concentrically stacked together.
= The cone-shaped rotor magnet 2-3 of the rotor assembly may consist of a plurality of disc-shaped magnets having different diameters, concentrically stacked together.
= In another embodiment of the invention shown in Figure 7 in sectional side view and Figure 8 in sectional top view, a flywheel system comprises a housing 3-0, a stator assembly, and a rotor assembly.
= The stator assembly comprises a cone-shaped stator magnet 3-1 having a substantially triangular cross section, securely attached to the housing 3-0.
= The rotor assembly has a central axis of rotation, and is co-axially placed relative to the stator assembly. The rotor assembly comprises a vertical shaft 3-2 made of a non-magnetic material, a ring-shaped rotor magnet 3-3 having a substantially triangular cross section, and a flywheel 3-4 made of a ferromagnetic material such as iron (Fe), cobalt (Co) or nickel (Ni) so that the rotor assembly can be set in motion by an external prime mover magnetically coupled to the flywheel. The vertical shaft 3-2 has a top portion and a bottom portion. The ring-shaped rotor magnet 3-3 is securely attached to the top portion of the vertical shaft 3-2. The flywheel 3-4 is securely attached to the bottom portion of the vertical shaft 3-2.
= Unlike the conventional flywheel system, the cone-shaped stator magnet 3-1 has the same sense of magnetisation as the ring-shaped rotor magnet 3-3. The cone-shaped stator magnet 3-1 forms inverse heart-shaped magnetic flux lines, and the ring-shaped rotor magnet 3-3 forms heart-shaped magnetic flux lines. An upward magnetic repulsion force (Fm) between the inverse heart-shaped magnetic flux lines of the cone-shaped stator magnet 3-1 and the heart-shaped magnetic flux lines of the ring-shaped rotor magnet 3-3 equals a downward gravitational force (Fg) by the rotor assembly in order to passively suspend the rotor assembly so that the rotor assembly is capable of rotating around the central axis of rotation, as shown in the schematic diagram of Figure 9.
= Magnetic flux lines flowing in a same direction indicate a stable pattern, while magnetic flux lines flowing in opposite directions indicate an unstable pattern. The stable magnetic flux line patterns at the air gap between the cone-shaped stator magnet 3-1 and the ring-shaped rotor magnet 3-3 in Figure 9 provide axial stability and radial stability. These stabilities are due to a cone-shaped well in a toroidal magnetic field, which is formed by a concentrated first magnetic pole and a distributed second magnetic pole. The stable force field counters any overturning tendencies of the magnets. The gravitational force is used to suppress "tilt" and "whirl" instabilities.
= The equilibrium in this configuration is analogous to the Lagrange Points between gravitational bodies in space.
= Preferably, the cone-shaped stator magnet 3-1 of the stator assembly and the ring-shaped rotor magnet 3-3 of the rotor assembly are made of rare-earth permanent magnet, which is an electrical insulator so that eddy current is not induced during operation.
= The cone-shaped stator magnet 3-1 of the stator assembly may consist of a plurality of disc-shaped magnets having different diameters, concentrically stacked together.
= The ring-shaped rotor magnet 3-3 of the rotor assembly may consist of a plurality of ring-shaped magnets having different diameters, concentrically stacked together.
= The housing 2-0 in Figure 4 and the housing 3-0 in Figure 7 may be hermetically sealed in a partial vacuum in order to reduce air resistance by rotational movement of the rotor assembly.
= The flywheel system may further comprise a bearing assembly securely attached to the housing and to the vertical shaft in order to provide additional stability. The bearing assembly may be placed above the flywheel or below the flywheel. The bearing assembly may be a magnetic bearing or a mechanical bearing.
The disc-shaped rotor magnet 1-3 is securely attached to the top portion of the vertical shaft 1-2. The flywheel 1-4 is securely attached to the bottom portion of the vertical shaft 1-2.
= The ring-shaped stator magnet 1-1 has the opposite sense of magnetisation to the disc-shaped rotor magnet 1-3. The ring-shaped stator magnet 1-1 forms magnetic flux lines, and the disc-shaped rotor magnet 1-3 forms magnetic flux lines. An upward magnetic repulsion force (Fm) between the magnetic flux lines of the ring-shaped stator magnet 1-1 and the magnetic flux lines of the disc-shaped rotor magnet 1-3 equal a downward gravitational force (Fg) by the rotor assembly in order to passively suspend the rotor assembly so that the rotor assembly is capable of rotating around the central axis of rotation, as shown in the schematic diagram of Figure 3 marked "Prior Art".
= Magnetic flux lines flowing in a same direction indicate a stable pattern, while magnetic flux lines flowing in opposite directions indicate an unstable pattern. The unstable magnetic flux line patterns at the air gap between the ring-shaped stator magnet 1-1 and the disc-shaped rotor magnet 1-3 in Figure 3 provide axial stability and radial instability. Although the diameter of the ring-shaped stator magnet 1-1 is different from the diameter of the disc-shaped rotor magnet 1-3, an eddy-current stabiliser 1-5 is required in order to overcome the radial instability. The gravitational force is used to suppress "tilt" and "whirl" instabilities.
= In one embodiment of the invention shown in Figure 4 in sectional side view and Figure 5 in sectional top view, a flywheel system comprises a housing 2-0, a stator assembly, and a rotor assembly.
= The stator assembly comprises a ring-shaped stator magnet 2-1 having a substantially triangular cross section, securely attached to the housing 2-0.
= The rotor assembly has a central axis of rotation, and is co-axially placed relative to the stator assembly. The rotor assembly comprises a vertical shaft 2-2 made of a non-magnetic material, a cone-shaped rotor magnet 2-3 having a substantially triangular cross section, and a flywheel 2-4 made of a non-magnetic material. The vertical shaft 2-2 has a top portion and a bottom portion. The cone-shaped rotor magnet 2-3 is securely attached to the top portion of the vertical shaft 2-2. The flywheel 2-4 is securely attached to the bottom portion of the vertical shaft 2-2.
= Unlike the conventional flywheel system, the ring-shaped stator magnet 2-1 has the same sense of magnetisation as the cone-shaped rotor magnet 2-3. The ring-shaped stator magnet 2-1 forms inverse heart-shaped magnetic flux lines, and the cone-shaped rotor magnet 2-3 forms heart-shaped magnetic flux lines. An upward magnetic repulsion force (Fm) between the inverse heart-shaped magnetic flux lines of the ring-shaped stator magnet 2-1 and the heart-shaped magnetic flux lines of the cone-shaped rotor magnet 2-3 equals a downward gravitational force (Fg) by the rotor assembly in order to passively suspend the rotor assembly so that the rotor assembly is capable of rotating around the central axis of rotation, as shown in the schematic diagram of Figure 6.
= Magnetic flux lines flowing in a same direction indicate a stable pattern, while magnetic flux lines flowing in opposite directions indicate an unstable pattern. The stable magnetic flux line patterns at the air gap between the ring-shaped stator magnet 2-1 and the cone-shaped rotor magnet 2-3 in Figure 6 provide axial stability and radial stability. These stabilities are due to a cone-shaped well in a toroidal magnetic field, which is formed by a concentrated first magnetic pole and a distributed second magnetic pole. The stable force field counters any overturning tendencies of the magnets. The gravitational force is used to suppress "tilt" and "whirl" instabilities.
= The equilibrium in this configuration is analogous to the Lagrange Points between gravitational bodies in space.
= Preferably, the ring-shaped stator magnet 2-1 of the stator assembly and the cone-shaped rotor magnet 2-3 of the rotor assembly are made of rare-earth permanent magnet, which is an electrical insulator so that eddy current is not induced during operation.
= The ring-shaped stator magnet 2-1 of the stator assembly may consist of a plurality of ring-shaped magnets having different diameters, concentrically stacked together.
= The cone-shaped rotor magnet 2-3 of the rotor assembly may consist of a plurality of disc-shaped magnets having different diameters, concentrically stacked together.
= In another embodiment of the invention shown in Figure 7 in sectional side view and Figure 8 in sectional top view, a flywheel system comprises a housing 3-0, a stator assembly, and a rotor assembly.
= The stator assembly comprises a cone-shaped stator magnet 3-1 having a substantially triangular cross section, securely attached to the housing 3-0.
= The rotor assembly has a central axis of rotation, and is co-axially placed relative to the stator assembly. The rotor assembly comprises a vertical shaft 3-2 made of a non-magnetic material, a ring-shaped rotor magnet 3-3 having a substantially triangular cross section, and a flywheel 3-4 made of a ferromagnetic material such as iron (Fe), cobalt (Co) or nickel (Ni) so that the rotor assembly can be set in motion by an external prime mover magnetically coupled to the flywheel. The vertical shaft 3-2 has a top portion and a bottom portion. The ring-shaped rotor magnet 3-3 is securely attached to the top portion of the vertical shaft 3-2. The flywheel 3-4 is securely attached to the bottom portion of the vertical shaft 3-2.
= Unlike the conventional flywheel system, the cone-shaped stator magnet 3-1 has the same sense of magnetisation as the ring-shaped rotor magnet 3-3. The cone-shaped stator magnet 3-1 forms inverse heart-shaped magnetic flux lines, and the ring-shaped rotor magnet 3-3 forms heart-shaped magnetic flux lines. An upward magnetic repulsion force (Fm) between the inverse heart-shaped magnetic flux lines of the cone-shaped stator magnet 3-1 and the heart-shaped magnetic flux lines of the ring-shaped rotor magnet 3-3 equals a downward gravitational force (Fg) by the rotor assembly in order to passively suspend the rotor assembly so that the rotor assembly is capable of rotating around the central axis of rotation, as shown in the schematic diagram of Figure 9.
= Magnetic flux lines flowing in a same direction indicate a stable pattern, while magnetic flux lines flowing in opposite directions indicate an unstable pattern. The stable magnetic flux line patterns at the air gap between the cone-shaped stator magnet 3-1 and the ring-shaped rotor magnet 3-3 in Figure 9 provide axial stability and radial stability. These stabilities are due to a cone-shaped well in a toroidal magnetic field, which is formed by a concentrated first magnetic pole and a distributed second magnetic pole. The stable force field counters any overturning tendencies of the magnets. The gravitational force is used to suppress "tilt" and "whirl" instabilities.
= The equilibrium in this configuration is analogous to the Lagrange Points between gravitational bodies in space.
= Preferably, the cone-shaped stator magnet 3-1 of the stator assembly and the ring-shaped rotor magnet 3-3 of the rotor assembly are made of rare-earth permanent magnet, which is an electrical insulator so that eddy current is not induced during operation.
= The cone-shaped stator magnet 3-1 of the stator assembly may consist of a plurality of disc-shaped magnets having different diameters, concentrically stacked together.
= The ring-shaped rotor magnet 3-3 of the rotor assembly may consist of a plurality of ring-shaped magnets having different diameters, concentrically stacked together.
= The housing 2-0 in Figure 4 and the housing 3-0 in Figure 7 may be hermetically sealed in a partial vacuum in order to reduce air resistance by rotational movement of the rotor assembly.
= The flywheel system may further comprise a bearing assembly securely attached to the housing and to the vertical shaft in order to provide additional stability. The bearing assembly may be placed above the flywheel or below the flywheel. The bearing assembly may be a magnetic bearing or a mechanical bearing.
Claims (16)
1. A flywheel system, comprising:
.circle. a housing;
.circle. a stator assembly comprising:
~ a ring-shaped stator magnet having an equilaterally triangular cross section, the equilaterally triangular cross section having an angle of pi/3 radian (60 degrees), the ring-shaped stator securely attached to the housing; and .circle. a rotor assembly having a central axis of rotation, the rotor assembly co-axially placed relative to the stator assembly, comprising:
~ a vertical shaft made of a non-magnetic material, the vertical shaft having a top portion and a bottom portion;
~ a cone-shaped rotor magnet having an equilaterally triangular cross section, the equilaterally triangular cross section having an angle of pi/3 radian (60 degrees), the cone-shaped rotor magnet securely attached to the top portion of the vertical shaft; and ~ a flywheel made of a ferromagnetic material such as iron (Fe), cobalt (Co) or nickel (Ni) so that the rotor assembly can be set in motion by an external prime mover magnetically coupled to the flywheel, the flywheel securely attached to the bottom portion of the vertical shaft;
the ring-shaped stator magnet having the same sense of magnetisation as the cone-shaped rotor magnet, an upward magnetic repulsion force between the inverse heart-shaped magnetic flux lines of the ring-shaped stator magnet and the heart-shaped magnetic flux lines of the cone-shaped rotor magnet passively suspending the rotor assembly so that the rotor assembly is capable of rotating around the central axis of rotation.
.circle. a housing;
.circle. a stator assembly comprising:
~ a ring-shaped stator magnet having an equilaterally triangular cross section, the equilaterally triangular cross section having an angle of pi/3 radian (60 degrees), the ring-shaped stator securely attached to the housing; and .circle. a rotor assembly having a central axis of rotation, the rotor assembly co-axially placed relative to the stator assembly, comprising:
~ a vertical shaft made of a non-magnetic material, the vertical shaft having a top portion and a bottom portion;
~ a cone-shaped rotor magnet having an equilaterally triangular cross section, the equilaterally triangular cross section having an angle of pi/3 radian (60 degrees), the cone-shaped rotor magnet securely attached to the top portion of the vertical shaft; and ~ a flywheel made of a ferromagnetic material such as iron (Fe), cobalt (Co) or nickel (Ni) so that the rotor assembly can be set in motion by an external prime mover magnetically coupled to the flywheel, the flywheel securely attached to the bottom portion of the vertical shaft;
the ring-shaped stator magnet having the same sense of magnetisation as the cone-shaped rotor magnet, an upward magnetic repulsion force between the inverse heart-shaped magnetic flux lines of the ring-shaped stator magnet and the heart-shaped magnetic flux lines of the cone-shaped rotor magnet passively suspending the rotor assembly so that the rotor assembly is capable of rotating around the central axis of rotation.
2. The flywheel system as defined in claim 1, in which the ring-shaped stator magnet of the stator assembly is made of rare-earth permanent magnet.
3. The flywheel system as defined in claim 1, in which the ring-shaped stator magnet of the stator assembly consists of a plurality of ring-shaped magnets having different diameters, concentrically stacked together.
4. The flywheel system as defined in claim 1, in which the cone-shaped rotor magnet of the rotor assembly is made of rare-earth permanent magnet.
5. The flywheel system as defined in claim 1, in which the cone-shaped rotor magnet of the rotor assembly consists of a plurality of disc-shaped magnets having different diameters, concentrically stacked together.
6. A flywheel system, comprising:
.circle. a housing;
.circle. a stator assembly comprising:
~ a cone-shaped stator magnet having an equilaterally triangular cross section, the equilaterally triangular cross section having an angle of pi/3 radian (60 degrees), the cone-shaped stator magnet securely attached to the housing; and .circle. a rotor assembly having a central axis of rotation, the rotor assembly co-axially placed relative to the stator assembly, comprising:
~ a vertical shaft made of a non-magnetic material, the vertical shaft having a top portion and a bottom portion;
~ a ring-shaped rotor magnet having an equilaterally triangular cross section, the equilaterally triangular cross section having an angle of pi/3 radian (60 degrees), the ring-shaped rotor magnet securely attached to the top portion of the vertical shaft; and ~ a flywheel made of a ferromagnetic material such as iron (Fe), cobalt (Co) or nickel (Ni) so that the rotor assembly can be set in motion by an external prime mover magnetically coupled to the flywheel, the flywheel securely attached to the bottom portion of the vertical shaft;
the cone-shaped stator magnet having the same sense of magnetisation as the ring-shaped rotor magnet, an upward magnetic repulsion force between the inverse heart-shaped magnetic flux lines of the cone-shaped stator magnet and the heart-shaped magnetic flux lines of the ring-shaped rotor magnet passively suspending the rotor assembly so that the rotor assembly is capable of rotating around the central axis of rotation.
.circle. a housing;
.circle. a stator assembly comprising:
~ a cone-shaped stator magnet having an equilaterally triangular cross section, the equilaterally triangular cross section having an angle of pi/3 radian (60 degrees), the cone-shaped stator magnet securely attached to the housing; and .circle. a rotor assembly having a central axis of rotation, the rotor assembly co-axially placed relative to the stator assembly, comprising:
~ a vertical shaft made of a non-magnetic material, the vertical shaft having a top portion and a bottom portion;
~ a ring-shaped rotor magnet having an equilaterally triangular cross section, the equilaterally triangular cross section having an angle of pi/3 radian (60 degrees), the ring-shaped rotor magnet securely attached to the top portion of the vertical shaft; and ~ a flywheel made of a ferromagnetic material such as iron (Fe), cobalt (Co) or nickel (Ni) so that the rotor assembly can be set in motion by an external prime mover magnetically coupled to the flywheel, the flywheel securely attached to the bottom portion of the vertical shaft;
the cone-shaped stator magnet having the same sense of magnetisation as the ring-shaped rotor magnet, an upward magnetic repulsion force between the inverse heart-shaped magnetic flux lines of the cone-shaped stator magnet and the heart-shaped magnetic flux lines of the ring-shaped rotor magnet passively suspending the rotor assembly so that the rotor assembly is capable of rotating around the central axis of rotation.
7. The flywheel system as defined in claim 6, in which the cone-shaped stator magnet of the stator assembly is made of rare-earth permanent magnet.
8. The flywheel system as defined in claim 6, in which the cone-shaped stator magnet of the stator assembly consists of a plurality of disc-shaped magnets having different diameters, concentrically stacked together.
9. The flywheel system as defined in claim 6, in which the ring-shaped rotor magnet of the rotor assembly is made of rare-earth permanent magnet.
10. The flywheel system as defined in claim 6, in which the ring-shaped rotor magnet of the rotor assembly consists of a plurality of ring-shaped magnets having different diameters, concentrically stacked together.
11. The flywheel system as defined in claim 1 or claim 6, in which the housing is hermetically sealed in a partial vacuum in order to reduce air resistance by rotational movement of the rotor assembly.
12. The flywheel system as defined in claim 1 or claim 6, further comprising:
o a bearing assembly securely attached to the housing and to the vertical shaft;
in order to provide additional stability.
o a bearing assembly securely attached to the housing and to the vertical shaft;
in order to provide additional stability.
13. The flywheel system as defined in claim 12, in which the bearing assembly is placed above the flywheel.
14. The flywheel system as defined in claim 12, in which the bearing assembly is placed below the flywheel.
15. The flywheel system as defined in claim 12, in which the bearing assembly is a magnetic bearing.
16. The flywheel system as defined in claim 12, in which the bearing assembly is a mechanical bearing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA2327492A CA2327492C (en) | 2000-11-10 | 2000-11-10 | Magnetically suspended flywheel system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA2327492A CA2327492C (en) | 2000-11-10 | 2000-11-10 | Magnetically suspended flywheel system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2327492A1 CA2327492A1 (en) | 2002-05-10 |
| CA2327492C true CA2327492C (en) | 2011-07-12 |
Family
ID=4167813
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2327492A Expired - Fee Related CA2327492C (en) | 2000-11-10 | 2000-11-10 | Magnetically suspended flywheel system |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2327492C (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012155170A1 (en) * | 2011-05-13 | 2012-11-22 | Empire Technology Development Llc | Energy storage system |
| CN110266215B (en) * | 2018-03-12 | 2021-08-27 | 李国坤 | Vertical permanent magnetic suspension device |
| WO2021005522A1 (en) * | 2019-07-08 | 2021-01-14 | Azamour Investment Corporation Incorporated | Rotary vane device |
| CN112505597B (en) * | 2020-10-16 | 2021-10-22 | 横店集团东磁股份有限公司 | Magnetic flux detection tool for annular permanent magnet |
-
2000
- 2000-11-10 CA CA2327492A patent/CA2327492C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CA2327492A1 (en) | 2002-05-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6657344B2 (en) | Passive magnetic bearing for a horizontal shaft | |
| US5831362A (en) | Magnet-superconductor flywheel and levitation systems | |
| JP3121819B2 (en) | Magnetic bearing device with permanent magnet that receives radial force applied to the shaft | |
| CN101771308B (en) | A kind of magnetic suspension rotor support system and magnetic suspension bearing and magnetic bias weight reducing device | |
| IE850634L (en) | Magnetic bearing | |
| JP2008537872A (en) | Method for stabilizing a magnetically levitated object | |
| US6213737B1 (en) | Damper device and turbomolecular pump with damper device | |
| US6175175B1 (en) | Levitation pressure and friction losses in superconducting bearings | |
| JPH06510165A (en) | High thrust and high stability magnet-superconductor system | |
| US5540116A (en) | Low-loss, high-speed, high-TC superconducting bearings | |
| US4983869A (en) | Magnetic bearing | |
| WO2002035108A1 (en) | Magnetic suspension bearing | |
| CN101737425A (en) | Monostable radial magnetic bearing with low power consumption and zero gravity action | |
| CA2327492C (en) | Magnetically suspended flywheel system | |
| Post et al. | Ambient-temperature passive magnetic bearings: Theory and design equations | |
| EP0795226A4 (en) | ||
| US6369476B1 (en) | High temperature superconductor bearings | |
| JP3554070B2 (en) | Superconducting magnetic bearing device | |
| US20130207496A1 (en) | System and method for performing magnetic levitation in an energy storage flywheel | |
| WO1997009664A1 (en) | Improvements in mixed-mu superconducting bearings | |
| Komori et al. | A hybrid-type superconducting magnetic bearing system with nonlinear control | |
| CN108547868B (en) | Semi-freedom degree radial magnetizing hybrid axial magnetic bearing | |
| CN100547900C (en) | Magnetic suspending wind turbine generator | |
| US4643034A (en) | Gyroscopically stabilized magnetic suspension system | |
| JPH08296645A (en) | Magnetic bearing device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |
Effective date: 20131113 |