Lift magnet mechanism for flywheel power storage systems

The present invention relates to conventional flywheel drive power storage systems, especially with respect to enhancements developed by current manufacturing capacity to smooth the magnetic flux density across discontinuities or segments present in permanent magnets.

reference In the prior art, the flywheel drive power storage system and its various related elements are described by Bitterly et al, Patent Document 1, Rosen et al, Patent Document 2, Patent Document 3, Patent Document 4, and Patent Document 5, Lyman. Patent Document 6 and Patent Document 7, Patent Document 8 and Patent Document 9 by Perper, Patent Document 10 by Miller, Patent Document 11 by Hiyama et al, Patent Document 12 by Nomura et al, Patent Document 13 by Conrad, Patent Document 13 by Huang et al. Patent Document 14, Patent Document 15 by Benedetti et al, Patent Document 16 by Schroeder et al, Patent Document 17 by Post, Patent Document 18, Patent Document 19, Patent Document 20, and Patent Document 21, Patent Document 22 by Merritt et al. , Fisher, Patent Document 23 and Patent Document 24, Cambie et. It can be found in Patent Documents 25 and 26 by al, Patent Document 27 by Everton, Patent Document 28 by Trat, Patent Document 29, Patent Document 30, and Patent Document 31, and Patent Document 32 by Kuroiwa.

Further specific to the present invention, Patent Document 33 uses electromagnets and permanent magnets to lift the rotor of the bearing used in the flywheel to extend the life of the bearing and reduce heat and eddy currents. It is described.

The present invention relates to the storage of electric power, which converts the kinetic energy stored by the inertial and mutual means of a rotating flywheel into electric power through power interface electronics and electromechanical energy conversion. The various component elements of the present invention are a high speed motor / generator with cooperative power electronics and magnetic bearings, an electronic feedback control servo mechanism to stabilize the magnetic bearings, and a motor / generator rotor that stores kinetic energy. And a vertical flywheel integrated with the rotating magnetic bearing element, a vacuum enclosure to reduce air resistance, a mechanical backup bearing that is not used during normal operation, and a fixation to safely accommodate the flywheel and enclosure. Including the energy absorption installation location.

Also, as shown in the US patents referenced above, means such as rechargeable electrochemical cells offer several uses, but include important issues such as containment space, leakage and life. I run into a very big problem. Therefore, a flywheel drive system can provide a different advantage than such a system. However, as flywheel power storage system designs evolve from small, physically constrained structures with minimal storage capacity to large capacity systems that utilize industrial-sized magnetic components that are common today, Material constraints and other inherent factors are occurring. In order to make the flywheel energy storage system a practical alternative system, the above problems must be overcome to facilitate maximizing energy storage and power output.

Due to the need for very large magnetic arrays and members in current applications, current manufacturing capacity limits magnetic arrays to structures containing coupled magnetic segments. When the stator faces the rotor directly, the permanent magnet arrangement induces eddy currents and excessive heat generation of the rotor due to the discontinuity inherent in the magnetic flux density across these segments at the rotor-stator interface. Therefore, what is needed to address this shortcoming is a mechanism and / or system that works to eliminate these problems by disabling or removing the discontinuity from the segment.

Moreover, in most of today's applications, the magnetic force generated by permanent magnets, electromagnets, or a combination of both is used to lift the rotor of the flywheel system. The magnetic force generated by the pair of fixed stators and rotors is usually very sensitive to the air gap that separates the stators and rotors. High sensitivity means a weak magnetic force when the gap is large, and an excessively strong magnetic force when the gap is small. A weak magnetic force in a large gap requires a design with either a stronger magnet or a higher current to lift the rotor, and an excessively strong magnetic force in a small gap could potentially damage the component if in failure. To do.

Previous failures of high capacity flywheel systems are often caused by overloading and overheating of touchdown ball bearings. When a pure electromagnet lift magnet is used, a failure occurs because a large lift force is required to interfere with electric power during normal operation. Since the lifting force is dissipated, the heavy rotor rides on the ball bearings, which heats the ball bearings in a short time due to the heavy load. Therefore, if the ball bearing fails, the high-speed rotor loses mechanical support and makes basically non-circular rotations that come into contact with the case. Therefore, exhaustion, sometimes catastrophe, and an explosion inside the case can occur.

Further, in a system that utilizes the magnetic force generated by a permanent magnet, an electromagnet, or a combination of both to lift the rotor, the magnetic force generated by the pair of fixed stators and rotors is relative to the air gap that separates the stator and rotor. Usually very sensitive. High sensitivity means that when the gap is large, a weak magnetic force is generated, and when the gap is small, an excessively strong magnetic force is generated. Large gap conditions where weak magnetic forces occur require a design with either stronger magnets or higher currents to lift the rotor, while excessively strong magnetic forces in small gaps are potentially components or systems in fault conditions. It may damage the whole.

Therefore, when studying a typical lift magnet design, what is needed is a low clearance sensitivity to ensure that the magnetic force is slightly stronger in the larger clearance configuration and significantly weaker in the smaller clearance configuration. It is a design that can provide magnetic force. Moreover, there is a need for a system, mechanism or operating method that minimizes the load on the ball bearings if the rotor falls onto the bearing in any potential failure mode. It also minimizes the power used by the lift magnet system to minimize heat generation for superior rotor control, as well as a system that prevents the high speed rotor from sticking to the stator in any potential failure mode. Need a system to do.

<p><patcit num="1"><text>U.S. Pat. No. 5,614,777</text></patcit><patcit num="2"><text>U.S. Pat. No. 567,595</text></patcit><patcit num="3"><text>U.S. Pat. No. 5,708,312</text></patcit><patcit num="4"><text>U.S. Pat. No. 5,770,909</text></patcit><patcit num="5"><text>U.S. Pat. No. 58,644,303</text></patcit><patcit num="6"><text>U.S. Pat. No. 3,860,300</text></patcit><patcit num="7"><text>U.S. Pat. No. 4,147,396</text></patcit><patcit num="8"><text>U.S. Pat. No. 3,791,704</text></patcit><patcit num="9"><text>U.S. Pat. No. 4,088,379</text></patcit><patcit num="10"><text>U.S. Pat. No. 5,627,419</text></patcit><patcit num="11"><text>U.S. Pat. No. 4,910,449</text></patcit><patcit num="12"><text>U.S. Pat. No. 5,760,510</text></patcit><patcit num="13"><text>U.S. Pat. No. 5,777,414</text></patcit><patcit num="14"><text>U.S. Pat. No. 5,319,844</text></patcit><patcit num="15"><text>U.S. Pat. No. 4,444,444</text></patcit><patcit num="16"><text>U.S. Pat. No. 5,844,339</text></patcit><patcit num="17"><text>U.S. Pat. No. 5,495,221</text></patcit><patcit num="18"><text>U.S. Pat. No. 5,783,885</text></patcit><patcit num="19"><text>U.S. Pat. No. 5,847,480</text></patcit><patcit num="20"><text>U.S. Pat. No. 5,861,690</text></patcit><patcit num="21"><text>U.S. Pat. No. 5,883,499</text></patcit><patcit num="22"><text>U.S. Pat. No. 5,705,902</text></patcit><patcit num="23"><text>U.S. Pat. No. 5,044,944</text></patcit><patcit num="24"><text>U.S. Pat. No. 5,311,092</text></patcit><patcit num="25"><text>U.S. Pat. No. 5,107,151</text></patcit><patcit num="26"><text>U.S. Pat. No. 5,677,605</text></patcit><patcit num="27"><text>U.S. Pat. No. 5,670,838</text></patcit><patcit num="28"><text>U.S. Pat. No. 3,969,005</text></patcit><patcit num="29"><text>U.S. Pat. No. 3,989,324</text></patcit><patcit num="30"><text>U.S. Pat. No. 4,094,560</text></patcit><patcit num="31"><text>U.S. Pat. No. 4,141,607</text></patcit><patcit num="32"><text>U.S. Pat. No. 4,799,809</text></patcit><patcit num="33"><text>U.S. Pat. No. 6,566,775</text></patcit></p>

<p> The present invention presented in the present application is not explicitly predicted, unclear, or even present from prior art mechanisms alone or any combination thereof. A flywheel drive power storage system adapted to compensate for the shortcomings and limitations mentioned above provides significant improvements for many useful uses. Therefore, some embodiments of the present invention are shown here.</p>

<p> An important object of the present invention is to improve the high capacity flywheel energy storage system, and especially to improve the wear of the inherent bearing, to control the magnetic flux, and to minimize the fluctuation of the required lift power. Therefore, it is crucial to create a system, subsystem, mechanism, or operating method that minimizes the load on the ball bearings when the high speed rotor is released and begins to plummet into the ball bearings in a potential failure mode.</p><p> An additional object of the present invention is to provide a flywheel power storage system with a motor / generator with minimal eddy current loss, where the rotor integrated with the first magnetically driven first bearing system is a mechanical bearing. Demonstrate the use of mechanical bearings only as a temporary backup to reduce wear.</p><p> Moreover, in any flywheel drive system, the general object of the present invention is an improved long life fly without significant power loss, excessive internal heating, vacuum loss, large scale management, explosion risk and high cost. To provide wheel batteries.</p><p> An additional object of the present invention is to prevent the high speed rotor from sticking to the stator due to extreme force and heat problems that occur under potential failure modes.</p><p> A further object of the present invention is to allow the flywheel system to operate in cold conditions, thus preventing inherent overheating and coupling or sticking of the rotor to the stator.</p><p> Another object of the present invention is to minimize the power used in the lift magnet system, which essentially minimizes heat generation and also maintains proper control of the rotor.</p><p> Another object of the present invention is an apparatus provided to cover a segmented magnet array and comprising a cylindrical steel pole mechanism to minimize eddy currents and ambient heat while matching with any configuration of the stator. Is to provide. Therefore, the use of the device essentially minimizes the heating of the stator windings, the derivation of thermal stresses, and the possibility of degassing of the resin molding when the resin material is utilized.</p><p> Another object of the present invention is to introduce a device provided with a magnetic force having a low gap sensitivity, which has a slightly strong magnetic force in a large gap and a significantly weak magnetic force in a small gap.</p><p> Other objectives are to eliminate the need for mechanical backup bearing lubricants to eliminate the causes of vacuum loss, frequent maintenance, and mechanical bearing failures.</p><p> Therefore, one particular object of the present invention is to provide a system that eradicates output spikes that occur in conventional systems due to operational-specific physical spatial problems with large circles of magnet members.</p><p> Accordingly, the accompanying enhancements of the improved flywheel battery system and component elements that achieve these objectives, as well as other benefits and enhancements, are presented here. These improvements to the technology are clearly understood from the following description of the invention when considered in connection with the accompanying drawings, in which more important features of the vehicle surveillance system outlined somewhat broadly are described. .. The detailed description below is better understood and this contribution to technology will be more invaluable.</p><p> There are additional features of the invention described below that form the appended claims. In this regard, prior to elaborating at least one embodiment of the invention, the invention is not limited to the application of structural details and component arrangements as described below or by description in the drawings. It should be understood that there is no such thing. The present invention can be implemented in other embodiments, and can be implemented and implemented by various methods. It should also be understood that the expressions and terms used in this application are for illustration purposes only and are not limiting.</p><p> It has been pointed out that these, along with other purposes of the invention with a variety of novel features that characterize the invention, are unique within the appended claims and form part of the present application. There is. In order to better understand the present invention, the operational benefits and specific objectives achieved by its use, reference should be made to the accompanying drawings and explanatory elements that describe preferred embodiments of the present invention.</p>

<figref num="1">A simplified cross-sectional assembly configuration diagram of the magnetic lift portion of the flywheel battery of the present invention is shown, with a stator housing, segment magnet array and permanent magnet array with steel columnar members or poles, coils, and rotors shown around the axis of rotation. Has been done.</figref><figref num="2">It is the top view of the permanent magnet arrangement which illustrated the segmentation state of the segment magnet arrangement.</figref><figref num="3">It is a block diagram which illustrated the steel column member or the pole.</figref><figref num="4">It is a side view of the rotor of a grooved embodiment.</figref><figref num="5">It is a side view of the rotor which illustrated the grooved structure of the chamfering embodiment.</figref><figref num="6">It is a finite element analysis result which illustrated the magnetic flux generated when the grooved rotor was used in the state where the gap between a rotor and a stator is small.</figref><figref num="7">This is a finite element analysis result showing the magnetic flux generated when a grooved rotor is used in a state where the gap between the rotor and the stator is large.</figref><figref num="8">It is a graph which showed that the difference between the lift force by a large rotor / stator gap and the lift force by a small rotor / stator gap becomes very small as compared with the lift force by a conventional rotor by using a grooved rotor.</figref><figref num="9">It is a side sectional view of a new assembly in an actual flywheel power storage system.</figref><figref num="10">A three-dimensional side cross-sectional view of the entire device illustrating a flywheel power storage system magnet ring device, a stator housing and assembly, a segment magnet array and a permanent magnet array with steel column members or poles, a coil, a gap between a rotor and a stator. , Or a rotor that includes a rotor / stator gap, and a groove.</figref><figref num="11">A side cross section showing a rotor mounted on a vertical spindle aligned with the edge of the flywheel, floating in the axial direction due to the attractive force between the high permeability steel at the top of the rotor and the interaction of the segmented magnet arrangement. It is a figure.</figref><figref num="12">It is an isometric sectional view of this invention which showed all the elements.</figref>

In a flywheel drive power storage system, the magnetic force generated by a permanent magnet, an electromagnet, or a combination of both is used to lift the rotor of the flywheel system. The magnetic force generated by the pair of fixed stators and rotors is usually highly sensitive to the air gap that separates the stator and rotor. High sensitivity means a weak magnetic force when the gap is large, and an excessively strong magnetic force when the gap is small.

Of the many embodiments of the present invention, first referring to FIG. 1, a simplified cross-sectional assembly configuration diagram of the magnetic lift portion of the flywheel power storage system magnet ring device 10 or flywheel battery is shown, the stator housing and An assembly 20, a permanent magnet arrangement with a segmented magnet array 31 and a steel column member 40 or pole 40, a coil 50, a rotor-stator gap or rotor / stator gap 60, and a rotor 70 including a groove 80 are shown.

Next, referring to FIG. 2, FIG. 3 is a top view of the permanent magnet array 30, and FIG. 3 showing individual segments 90 of the magnet array is a configuration diagram showing a steel column member 40 or a pole 40, which members. The 40 is designed to compensate for the discontinuity of the segment magnet array 31 and the individual segments 90, which is problematic because it induces changes in the magnetic flux that generate heat in the rotating member.

FIG. 4 is a side view of the rotor 70, illustrating a new grooved structure 80, which allows for more surface area for additional flux leakage to the wall and thus fluctuations in lift force. Can be controlled more quickly. FIG. 5 is a side view of the rotor 70 showing the grooved structure 80 of the chamfered variant 81, which allows for additional surface area for additional flux leakage to the wall and thus the variation in lift force. You can control it more quickly.

FIG. 6 is a finite element analysis result showing the magnetic flux 101 generated when the grooved rotor 80 is used in a state where the gap between the rotor 70 and the stator housing and the assembly 20 is small. Similarly, FIG. 7 is a finite element analysis result showing the magnetic flux 102 generated when the grooved rotor is used in a state where the gap between the rotor and the stator is large.

As shown in the graph of FIG. 8, the difference between the lift force due to the large rotor / stator gap and the lift force due to the small rotor / stator gap 121 is the lift force due to the conventional rotor 122 due to the use of the grooved rotor 80. Very small compared to the difference.

FIG. 9 shows a side sectional view of the magnetic ring or magnetic lift system 10 of the present invention in an actual flywheel power storage system. FIG. 10 is a three-dimensional side cross-section of the entire device, with a flywheel power storage system magnet ring device 10, a stator housing and assembly 20, a segment magnet array 31 and a permanent magnet array 30 with a steel column member 40 or pole 40, A rotor 70 including a coil 50, a rotor and stator gap, or a rotor / stator gap 60, and a slot / groove 80 is shown.

Referring to FIG. 11, the rotor 70 mounted on the vertical spindle 71 and the flywheel edge 120 is a non-rotating segment magnet array 31, with high magnetic permeability steel or other suitable material located at the top of the rotor 70, and Axial by attractive force between non-rotating, high magnetic permeability, annular steel column member 40 or pole 40 located on the upper and lower sides of the non-rotating, annular, axially magnetized permanent magnet array 30. Ascend to. The concentric coil 50, which acts as an electromagnet, provides a bidirectional drive current, and the overall novel rotor provides an essentially stable centering force by the same magnetic field that provides axial levitation to the flywheel edge 120. ..

The ability to magnetically levitate the flywheel edge during operation, especially because iron, high permeability steel or magnet members are not affected by continuous flux cycles and are not affected by significant changes in flux due to rotor rotation. Can greatly reduce the normal wear of bearings, magnetic members and steel members and also minimize the adverse effects of, for example, eddy current loss, plastic deformations or the like. This state is held particularly correctly when the steel column member of the present invention replaces a permanent magnet that matches the rotor, smoothing the magnetic flux.

To avoid overloading and overheating of the ball bearings if the rotor falls into the bearing system, as shown in the present application, the present invention ensures that the ball bearing system is not overloaded and does not fail the electromagnet system. To introduce a hybrid type lift magnet system that includes a permanent magnet array that provides most of the lift force. This permanent magnet array is made from segmented magnets covered by magnetic steel poles that slide the magnetic flux density to avoid eddy current loss and rotor heat generation. The electromagnets of the lift magnet system of the present invention provide a small lift force to control the rotor / stator gap.

With the permanent magnet arrangement of the present invention, weaker currents and power are required of the electromagnet. While the grooved rotor provides a relatively constant lift force, the flywheel system of the present invention operates and stays cold with less heat generation. The grooved rotor design of the present invention as compared to conventional rotors without a grooved device provides a sufficiently large lift force to facilitate the ascent of the rotor when the rotor / stator gap is large. In order to keep the lift force substantially constant when the rotor approaches the stator, a nearly constant force prevents the rotor from sticking to the stator in any possible failure mode. Thus, in the present invention, the annular steel pole is guided to eradicate magnetic flux changes and the grooved features of the rotor are guided to reduce force sensitivity.

Although some embodiments of the present invention have been shown as examples, it is clear that further embodiments can be developed within the spirit and technical scope of the invention. However, it should be especially understood that such improvements and modifications are made within the spirit and technical scope of the invention as described by the appended claims.

10 Flywheel power storage system Magnet ring device 20 Stator housing and assembly 30 Permanent magnet array 31 segment magnet array 40 Steel column member or pole 50 coils 60 Rotor / stator gap 70 rotor 71 Vertical spindle 80 grooves 90 segments