WO2018029553A1

WO2018029553A1 - Energy storage apparatus and process for storing and managing energy using said apparatus

Info

Publication number: WO2018029553A1
Application number: PCT/IB2017/054324
Authority: WO
Inventors: Stefano FABBRI
Original assignee: Fabbri Stefano
Priority date: 2016-08-10
Filing date: 2017-07-18
Publication date: 2018-02-15
Also published as: IT201600084463A1

Abstract

The present invention relates to an energy storage device comprising at least one storage unit (1, 101, 202, 203, 204) comprising at least one flywheel (5) operatively associated with at least one flywheel charging interface (20, 22, 25, 26, 27, 36, 37) capable of transforming electrical power from at least one source external to the flywheel into an electromotive force capable of pushing the flywheel into rotation, and/or at least one releasing interface of energy taken from the flywheel (20, 22, 25, 26, 27, 36, 37) capable of transforming the kinetic energy of the flywheel into electrical power to be released outside the flywheel, characterized in that the device comprises a control unit (30) capable of modifying the operating parameters of the at least one interface. The invention relates also to a process for storing and managing energy through such device.

Description

ENERGY STORAGE APPARATUS AND PROCESS FOR STORING AND MANAGING ENERGY USING SAID APPARATUS

* * * * *

DESCRIPTION

The present invention relates to an energy storage device and an energy storage and management process. In particular, the invention relates to the field of flywheel accumulators.

The need to store energy to use it when required and/or to transform it is known in all fields.

However, today' s systems are not very efficient because they are mainly based on chemical batteries, such as for example lead or lithium ones. As is known, they have a performance that deteriorates over time up to depletion. This limits the application and spreading of many technologies that would benefit from more performing storage systems.

It is therefore a general object of the present invention to wholly or partially resolve the problems of the known technique, and in particular to provide a storage device that has a very long useful life and which performance does not deteriorate during its operating life or which performance is not limited.

It is a preferred object of the present invention to provide a storage device that is highly adaptable to the changing conditions of supply, residual charge and charge requirement that may occur during operation.

It is another preferred object of the present invention to provide a storage device that is simple and affordable to make.

According to a first general aspect, the invention relates to an energy storage device comprising at least one storage unit comprising at least one flywheel operatively associated with at least one flywheel charging interface capable of transforming electrical power from at least one source external to the flywheel into an electromotive force capable of pushing the flywheel into rotation, and/or at least one interface for releasing energy taken from the flywheel capable of transforming the kinetic energy of the flywheel into electrical power to be released outside the flywheel, where the charging interface and the releasing interface are preferably without mechanical contact (for example, brushless), characterized in that the device comprises at least one control unit capable of modifying the operating parameters of the device, in particular the device comprises at least two interfaces, where each interface comprises a plurality of magnetic zones arranged on a first circumference about the rotation axis of the flywheel and a plurality of conductor material windings arranged on a second circumference about said axis facing said first circumference, where the conductor material windings are operatively coupled to the magnetic zones, the flywheel drags them into rotation with respect to one another or vice versa, and where the interfaces differ from one another at least for one of the following parameters: number of magnetic zones, number of conductor material windings, construction characteristics of the conductor material windings, magnetic field of the magnetic zones, distance of the flywheel from the rotation axis, the modification of the operating parameters of the device comprises at least the choice of the interface to be activated as charging interface and/or the choice of the interface to be activated as releasing interface.

Advantageously, the flywheel device resolves the problem of the duration over time of the storage capacity with respect to common batteries, moreover the dynamism of the interfaces allows an increased level of adaptability of the charge energy conditions of the flywheel, and/or those required by a possible external charge to be supplied and/or the ones of a supply source of the storage device. Moreover, the modification of the interface features may increase the duration of the charge.

Preferably, to increase the adaptability of the device and its performance spectrum, it is preferable for there to be at least two interfaces and for the control unit to be capable of modifying the operating parameters thereof independently of each other.

Preferably, each interface is capable of being activated indifferently by the control unit as charging interface or as releasing interface. This increases the versatility of the device.

According to certain preferred embodiments, at least one interface comprises at least one magnetic zone and at least one conductor material winding, one of the two being dragged into rotation with respect to the other by the flywheel, where the conductor material winding is operatively coupled to the magnetic zone and said operating parameters comprise at least the distance between the conductor material winding and the relative magnetic zone.

Such a constructive system appears particularly simple and affordable.

Preferably, the conductor material windings and/or the magnetic zones of at least one interface may selectively translate parallel to the rotation axis of the flywheel to be coupled operatively to other magnetic zones and/or conductor material windings to form a new interface with different features from pre-existing interfaces, where said modification of operating parameters of the device comprises at least the choice of the conductor material windings and of the magnetic zones to be coupled to form the at least one other interface and the translation to form such interface.

According to certain preferred embodiments of the invention, the device comprises a plurality of storage units with the same features indicated for the devices described above, where the flywheels of each unit can be rotated independently of one another and where the various units are capable of exchanging energy between one another.

According to certain preferable general features of the invention, the exchange of energy occurs by exchanging electrical power between the interfaces of the units and/or by dragging flywheels into rotation by magnetic attraction, where the flywheels that can be dragged into rotation with respect to one another are movable closer to and further away from one another to activate or deactivate such dragging on control of the control unit.

According to certain preferred embodiments of the invention, the device comprises a plurality of storage units according to any one of the preceding claims, where the flywheels of each unit can be rotated independently of one another, at least one connection to an external electric charge and at least one connection to a supply source of external electric current, where the control unit is programmed to control taking the energy to be sent to the charge from the unit with the flywheel with the energy level and the interface most suitable for supplying the charge. For example, the choice is made according to the frequency, the current or voltage intensity required by the charge and that can be obtained with the interface of the flywheel at the rotation speed of the flywheel.

The operating unit is then programmed to control the integration of the energy lost by such a flywheel during the supply of the charge by shunting it from one or more of the others; preferably the control unit is also programmed to store the energy from the external source in a flywheel up to a predetermined threshold, and to continue the storage in sequence in the other flywheels .

According to a second general aspect, the invention relates to a process for storing and managing energy, characterized in that it comprises the steps of:

- preparing a storage device according to any one of the preceding claims;

- connecting the device to an external electrical power source;

- connecting the device to an external electric charge;

- supplying the electric current of the source to the charge after storing it in the at least one flywheel. According to certain preferred embodiments of the invention, the process is characterized in that it stores the energy of the source and supplies it to the charge in differed periods and/or with differed parameters.

According to certain preferable general features of the invention, the process comprises the steps of:

- preparing a plurality of storage units (202, 203, 204) according to any one of claims 1 to 4, arranging them capable of exchanging energy between one another, and with the respective flywheels that can be rotated independently of one another;

- exchanging energy between at least one unit and the charge by selectively activating at least one interface and/or the translation of at least one conductor material winding of the unit according to the current parameters required by the charge;

- exchanging energy between the units to integrate the energy of the flywheel of the unit that supplies the charge, where the exchange occurs according to one of the following methods, selected according to the charge parameters of the flywheels:

a) by activating at least one interface (20, 22, 25, 26, 27, 36, 37),

b) and/or by activating the translation of at least one conductor material winding or of at least one magnetic zone,

c) and/or by magnetically dragging at least two flywheels of two units into rotation with each other. Further features and advantages of the present invention will be more evident from the following detailed description of preferred embodiments thereof made with reference to the appended drawings and given by way of a non-limiting indicative example. In such drawings :

- figure 1 diagrammat ically shows a sectional side view of an embodiment with a single storage unit of a storage device according to the present invention;

- figures 2 and 3 show a plan view of two respective operating positions of the device in figure 1;

- figures 4 and 5 show a sectional side view of two respective operating positions of a storage device according to an alternative embodiment of the invention;

- figure 6 shows a sectional side view of an embodiment of a storage device comprising a plurality of storage units;

- figures 7 and 8 show a sectional side view of other respective alternative embodiments of storage device according to the invention.

Figures 1, 2 and 3 show an energy storage device according to the present invention, indicated as a whole with reference number 1.

The device comprises a flywheel 5 that can be rotated about an axis X with respect to a support 10.

The flywheel comprises a first series 15 of magnetic zones 14 arranged circumferent ially side-by-side one another along the periphery of the flywheel 5.

The flywheel comprises a second series 18 of magnetic zones 16 arranged circumferent ially side-by-side one another along the periphery of the flywheel 5 and axially separate from the first series.

The magnetic zones 14 and 16 are for example, made by means of permanent magnets fixed to the flywheel.

The support 10 supports a first series 20 of solenoids 19 arranged circumferent ially side-by-side one another to be facing the first series of magnets 15.

The support 10 also supports a second series 22 of solenoids 21 arranged circumferent ially side-by-side one another to be facing the second series of magnets 18.

The storage device 1 comprises two energy exchange interfaces 25 and 26 comprising respectively the series of magnets 15 and the series of solenoids 20, the series of magnets 18 and the series of solenoids 22.

The exchange interfaces herein indicated are examples of energy exchange without mechanical contact, but they do not exclude the use of other interfaces .

Each interface 25, 26 may be used indifferently as energy charging interface and energy releasing interface .

Charging interface means an interface capable of transforming electrical power from at least one source external to the flywheel into an electromotive force capable of pushing the flywheel into rotation and charging it with kinetic energy.

Releasing interface means an interface capable of transforming the kinetic energy of the flywheel into electrical power to be released outside the flywheel.

The level of energy stored by the flywheel may be for example, estimated by the rotation speed thereof.

Each interface comprises an electrical connection towards its own exterior, indicated with reference numbers 28 and 29, that can be exploited at inlet and/or outlet for said charging and/or releasing.

The solenoids 19 and 21 of each series are movable closer to and further away from the respective magnets 14 and 16 on control of a control unit 30.

The two series of solenoids 20 and 22 are movable independently of each other, the distances D and d of the respective series of magnets 15 and 18 may therefore be modified independently of each other.

- Figures 2 and 3 show a plan view of two configurations that can be taken on by the interface 25, characterized in that they have different distances of the solenoids 20 from the magnets 15.

To allow the radial translation of the solenoids

20 and 22, they are fixed to the support 10 with the interposition of translation devices 32 controlled by the control unit 30.

In use, the device 1 may be used for example, as accumulator and/or as uninterruptible power supply and/or current parameter corrector.

The two interfaces 25 and 26 may indeed be electrically connected to the outside respectively with an electric current source, such as the public grid or a generating device from renewable sources, and a charge such as the household line.

The control unit 30 may be programmed to vary the distances d and D so as to store more or less energy in the unit according to the state of the flywheel, and/or to correct the anomalies of the network current and/or the current from another device before distributing it to the charge and/or for integrating the energy absorbed by a charge .

The following are certain preferred application examples :

- auxiliary accumulator to be used in the case of blackouts ;

- accumulator of energy generated by photovoltaic panels and/or wind farms when the inverters are deactivated because operation falls outside the minimum or maximum range;

- accumulator of photovoltaic and/or wind energy of stand-alone systems;

- recovery of the energy due to unbalancing of the phases in three-phase systems;

- accumulation of energy in any case in which the generation is greater than the need to supply it when the request is greater than the generation.

According to one possible variant of the device 1, there is only one of the two interfaces and the control unit 30 is capable of modifying its operation from charging interface to releasing interface and vice versa. The interface here maintains the translatability of the solenoids.

The successive drawings show other embodiments of the invention, where equal or similar elements to the ones described above are indicated with the same reference numbers or with the same numbers increased by 100 or a multiple thereof. Figures 4 and 5 show a storage device 101 which differs from the preceding device 1 mainly for the fact that it has three interfaces 25, 26 and 27 associated with a single flywheel 5 which are built like the ones described above.

The interfaces differ two-by-two for at least one feature, such as for example, the number of magnetic zones, the number of solenoids, the number of windings of the solenoids, the diameter of the windings of the solenoids, the diameter of the wire wound to create the solenoids, the flow of magnetic field, etc.

Each interface 25, 26, 27 is capable of being kept inactive, of being activated as charging interface, and of being activated as releasing interface. The choice of state of the interfaces is made by the control unit 30 according to the capabilities of each interface compared with the energy stored in the flywheel, the electrical power possibly required by the charge and the electrical power possibly available at the device inlet.

The solenoids in this embodiment are translatable parallel to the rotation axis X of the flywheel, as indicated by the arrow S, to face the magnetic zones of another interface and form new interfaces with different features from the starting ones.

In the choice of the interfaces to be activated, the control unit 30 also considers the new interfaces that may generate the axial translation, and may control the translation required.

According to a particularly simple embodiment, the solenoids are all integral in translation in direction S, for example being integral with a slide 40 that is movable in axial translation in direction S. The translation is of such entity that the new operating couplings between solenoids and magnetic zones form at least two interfaces, such as for example the ones indicated with 36 and 37 in figure 5.

Alternatively, the solenoids of at least one interface may be translatable in the direction X independently of the other interfaces, whereby there also may be one new interface alone for this path. Figure 6 shows a further embodiment of the invention indicated as a whole with reference number 201.

The storage device 201 comprises a plurality of storage units 202, 203 and 204 operatively acting in conjunction with one another.

Each storage unit is constructively made like any one of the storage devices described above, with the exception that the control unit 30 is common to all.

In particular in the example shown, unit 202 and unit 204 are constructively made like the device 1 in figures 1 to 3, and the unit 203 is constructively made like the device in figures 4 and 5.

The units 202, 203 and 204 therefore have one flywheel 5 each.

In use, the operating unit 30 acquires, over real time, information on the charging state of each flywheel, for example by means of speed sensors, on the features of the electric current possibly transmitted at the input to the storage device 201 by at least one external source, and on the features of the electric current possibly required at the outlet from the storage device 201 by at least one external charge.

According to this information, the operating unit makes the most suitable interfaces 20, 22, 25, 26, 27, 36, 37 active in real time and creates electrical exchange connections between the interfaces activated of various units and/or between the interfaces activated and the source and/or the charge. In such a manner, it is capable of recharging at least one of the flywheels and/or of supplying energy from at least one of the flywheels to the charge and/or of integrating the energy lost by the flywheel that supplies the charge by means of the energy of at least one of the other flywheels.

It is worth noting that flywheel coaxiality or proximity is not required in order to only exchange electrically between the units: the electrical connection is sufficient.

In addition or alternatively to the energy exchanges between flywheels by means of electrical connections, a more direct exchange of kinetic energy by means of mutual dragging in rotation could be interesting.

Figure 6 shows an example of it, with arrow SI showing that the flywheels of the units 203 and 204 may attract each other magnetically and may vary their axial distance on control of the control unit 30. Said flywheels here are coaxial and supported by a common fixed support .

Except when a possible magnetic dragging occurs, since the flywheels of the present invention are independent from each other in rotation, they are capable of rotating at different speeds and therefore of storing various levels of energy.

The exchanges of energy between flywheels make possible also a possible preliminary step prior to supplying a charge, in which if the energy level of a flywheel preselected for supplying is not optimal, it is brought to a level desired by accelerating or slowing down the flywheel by shunting energy from another flywheel or releasing it thereto.

Let's suppose for example, that in an initial condition, the flywheel of the unit 202 is stationary, that the flywheel of the unit 203 rotates at 5000 revolutions/minute and that the flywheel of the unit 204 rotates at 3000 revolutions/minute.

In order to put the flywheel of the unit 202 into rotation, the control unit may provide the control to extract energy for example, from the fastest flywheel, that is the one of unit 203, by means of the most suitable interface, let's suppose for example, interface 25. The energy extracted is emitted into the flywheel of the unit 202 by means of the most suitable interface, let's suppose for example 22. The choice of the pairs of interfaces to be used is made by the control unit 30 according to the parameters of the interfaces and the energies to be transferred.

When the flywheel of the unit 202 has reached a desired rotation state, only the energy required to keep it at a constant speed may continue to be supplied thereto. If energy is to be taken from the flywheel of the unit 202 to be supplied to a charge, for example after bringing it to the speed required to supply the current required by the charge by means of a free interface, the speed of the flywheel may be kept constant by integrating the energy it loses in the supply by means of the energy of another flywheel.

If the device is connected to an external source of electrical power, the losses of energy of the flywheel may be compensated for with energy from the source rather than from another flywheel, especially if all the flywheels are in the maximum charge state, which generally coincides with a maximum rotation speed.

Figure 7 shows an alternative embodiment of the storage device, indicated as a whole with reference number 301.

The device 301 differs from the preceding devices because the solenoids and the magnets are facing the axial rather than the radial direction. In the example shown, two interfaces 25 and 26 are indicated. This facilitates making a possible translation device 32 if a solution is to be implemented in which the distances between solenoids and magnets can be modified. In this case indeed, the translation device 32 may comprise a plate 60 movable in translation capable of supporting at least all the solenoids of one interface.

Figure 8 shows a further alternative embodiment indicated as a whole with reference number 401, that summarises various optional features.

They include the arrangement of the interfaces on various axial levels, for example on a first axial side of the flywheel, interfaces 25 and 50 are indicated placed at two different levels, and two interfaces 26 and 51 are indicated on the opposite side, they also on different axial levels from each other. This may be useful for example, for increasing the number of interfaces associable with a same flywheel.

It is worth noting that the interfaces may be placed also at various distances from the rotation axis X of the flywheel, for example radii R and r are indicated. This means that here, such radial distances also may be considered by the control unit 30 in the choice of the interface to be activated.

The example in figure 8 in general shows also that it is possible to make an embodiment comprising both interfaces with variable distances between solenoids and magnets (see 25 and 26) and fixed interfaces (see 50, 51) .

Those skilled in the art naturally will consider possible the variants of the device 401 with all the fixed interfaces or with all the variable distance interfaces .

In general, it is worth noting that there is no limit to the type and number of storage units that may be added together to form the storage device, like there is no limit to the number of interfaces per unit.

It is also worth noting that the features of the embodiments and variants hereto described and shown are intended to be combinable with one another, when possible .

As is noted, in general a storage unit is defined by the presence of a flywheel, whereby it is intended for there to be as many storage units as there are flywheels.

In general, the solenoids are indicated as examples of conductor material windings and may be replaced with any winding capable of generating an electromotive force or a current due to the interaction with a magnetic field.

Naturally, the embodiments and variants hereto described and shown are by mere way of example and those skilled in the art may make several modifications and variants in order to meet specific and contingent needs, including for example the combination of said embodiments and variants, all moreover contained within the scope of protection of the present invention defined by the following claims.

Claims

1. An energy storage device comprising at least one storage unit (1, 101, 202, 203, 204) comprising at least one flywheel (5) operatively associated with at least one flywheel charging interface (20, 22, 25, 26, 27, 36, 37) capable of transforming electrical power from at least one source external to the flywheel into an electromotive force capable of pushing the flywheel into rotation, and/or at least one releasing interface of energy taken from the flywheel (20, 22, 25, 26, 27, 36, 37) capable of transforming the kinetic energy of the flywheel into electrical power to be released outside the flywheel, characterized in that the device comprises at least one control unit (30) capable of modifying the operating parameters of the device, in particular the device comprises at least two interfaces, where each interface (20, 22, 25, 26, 27, 36, 37) comprises a plurality of magnetic zones (14, 16) arranged on a first circumference about the rotation axis (X) of the flywheel and a plurality of conductor material windings (19, 21) arranged on a second circumference about said axis (X) facing said first circumference, where the conductor material windings are operatively associated with the magnetic zones, the flywheel drags them into rotation with respect to one another or vice versa, and where the interfaces (20, 22, 25, 26, 27, 36, 37) differ from one another at least for one of the following parameters: number of magnetic zones, number of conductor material windings, construction characteristics of the conductor material windings, magnetic field of the magnetic zones, distance of the flywheel from the rotation axis, the modification of the operating parameters of the device comprises at least the choice of the interface to be activated as charging interface and/or the choice of the interface to be activated as releasing interface.

2. A device according to the preceding claim, characterized in that the conductor material windings (19, 21) and/or the magnetic zones of at least one interface (20, 22, 25, 26, 27, 36, 37) may selectively translate parallel to the rotation axis (X) of the flywheel to be coupled operatively to other magnetic zones and/or conductor material windings (14, 16) to form a new interface (36, 37) with different features from pre-existing interfaces, where said modification of operating parameters of the device comprises at least the choice of the conductor material windings and of the magnetic zones to be coupled to form the at least one other interface and the translation to form such interface .

3. A device according to any one of the preceding claims, characterized in that the control unit is capable of modifying the operating parameters of the interfaces independently of one another.

4. A device according to claim 3, characterized in that said operating parameters of the interfaces that can be modified by the control unit comprise at least the distance (D, d) in radial direction between the conductor material winding and the relative magnetic zone.

5. A device according to any one of the preceding claims, characterized in that it comprises a plurality of storage units (202, 203, 204) with the same features indicated in any one of the preceding claims, where the flywheels (5) of each unit can be rotated independently of one another and where the various units are capable of exchanging energy between one another.

6. A device according to the preceding claim, characterized in that the exchange of energy occurs by exchanging electrical power between the interfaces (20, 22, 25, 26, 27, 36, 37) of the units and/or by dragging flywheels into rotation by magnetic attraction, where the flywheels that can be dragged into rotation with respect to one another are movable closer to and further away from one another (SI) to activate or deactivate such dragging on control of the control unit (30) .

7. A device according to claim 5 or 6, comprising a plurality of storage units (202, 203, 204) according to any one of the preceding claims, where the flywheels of each unit can be rotated independently of one another, at least one connection to an external electric charge and at least one connection to a supply source of external electric current, where the control unit is programmed to control taking the energy to be sent to the charge from the unit with the flywheel with the energy level and the interface most suitable for supplying the charge, and to control the integration of the energy lost by such flywheel by shunting it from one or more of the others, preferably the control unit (30) is also programmed to store the energy from the external source in a flywheel up to a predetermined threshold, and to continue the storage in sequence in the other flywheels.

8. A process for storing and managing energy, characterized in that it comprises the steps of:

- preparing a storage device according to any one of the preceding claims;

- connecting the device to an external electrical power source;

- connecting the device to an external electric charge ;

- supplying the electric current of the source to the charge after storing it in the at least one flywheel.

9. A process according to the preceding claim, characterized in that it stores the energy of the source and supplies it to the charge in differed periods and/or with differed parameters.

10. A process according to claim 8 or 9, comprising the steps of:

a) by activating at least one interface (20, 22, 25, 26, 27, 36, 37),

c) and/or by magnetically dragging at least two flywheels of two units into rotation with each other.