Method and system for storing energy

Abstract

A system (100) for storing energy in the form of gravitational potential energy, comprising a plurality of weights (140); a lower station (110) and an upper station (120), each station being arranged to receive and hold a weight; a cableway (130) comprising a transfer cable (131), an electric motor (132) and a generator (133), the cableway (130) being arranged to transport a weight back and forth between the stations, the weight being arranged to be attached to the transfer cable at a station, the cableway being arranged to activate the electric motor to transport the weight between the stations; the cableway is further arranged to activate the generator while generating electrical energy during transport of the weight between the stations. The invention also relates to a method.

Description

Technical Field

[0001] The present invention relates to a method and system for storing energy. In particular, the present invention relates to the use of a cableway to convert and store electrical energy in the form of gravitational potential energy. The present invention also relates to the development and use of such stored energy by converting the stored gravitational potential energy into electrical energy. Background Art

[0002] As society becomes increasingly electrified, there is an increasing need for intermediate storage of electrical energy. Many proposals have been made in this regard.

[0003] For example, the use of batteries based on chemical reactions and phase changes is widely used. However, batteries are often associated with scalability issues. In addition, batteries often have a limited lifespan. Batteries also often use rare materials that can be expensive and difficult to recycle.

[0004] It has also been proposed to store energy in the form of chemicals produced that can be used later in a reverse chemical reaction. Hydrogen, for example, is widely used as such an intermediate storage substance. This has also proven difficult to scale up and has huge efficiency losses.

[0005] In other cases, hydroelectric solutions are used, in which water is pumped between reservoirs at different heights. Such solutions usually imply large-scale modifications of the natural environment and are usually accompanied by considerable efficiency losses.

[0006] There are other examples of previously proposed solutions that address similar issues of environmental impact, cost, difficulty in scaling, and inefficiency.

[0007] As society becomes increasingly reliant on renewable electricity, this is leading to a shortage of quickly regulated energy production in some regions. Summary of the invention

[0008] The present invention solves at least some of the above problems and provides an energy storage solution that is scalable, energy-efficient and cost-effective, robust, reliable and environmentally friendly.

[0009] Therefore, the present invention relates to a system for storing energy in the form of gravitational potential energy, the system comprising: a plurality of weights; a first station below, arranged to receive and hold the weights, and a second station above, arranged to receive and hold the weights; a cableway, arranged to transport the weights back and forth between the first station and the second station, the cableway comprising a transmission cable, an electric motor and a generator, the weights being arranged to be attached to the transmission cable at the first station, the cableway being arranged to activate the electric motor to transport a plurality of the weights by converting available electrical energy into the gravitational potential energy of the weights when the weights are transported from the first station to the second station by the cableway; the cableway being arranged to transport a plurality of the weights in a gravitational field from the second station to the first station by gravity, and activating the generator to convert the potential energy into electrical energy.

[0010] Furthermore, the present invention relates to a method for storing energy in the form of gravitational potential energy, the method comprising: a first providing step of providing a plurality of weights which are attached to a conveying cable of a cableway at a first station; a first energy conversion step of converting available electrical energy into potential energy using an electric motor by moving a plurality of the weights, the weights being transported from the first station to a second station along the cableway, the second station being located higher than the first station, the cableway being driven by the electric motor and transporting the weights from the first station to the second station; an energy storing step, wherein the weights are maintained at the second station; and a second energy conversion step, wherein the gravitational potential energy is converted into electrical energy by allowing the weights to move in a gravitational field as the weights are transported from the second station along the cableway, the potential energy being converted into electrical energy using a generator loaded by the weights. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Below, the present invention will be described in detail with reference to exemplary embodiments of the present invention and the accompanying drawings, in which:

[0012] Figure 1 is a simplified view of the system seen from the side;

[0013] Figure 2 is corresponding to Figure 1 A top view of

[0014] Figure 3 is a flow chart illustrating a method;

[0015] Figure 4 It is a simplified view of a heavy object;

[0016] Figure 5 is a simplified view of a stack of heavy objects;

[0017] Figure 6 is a simplified view of the site;

[0018] Figure 7 is a perspective view of an exemplary site;

[0019] Figure 8 is a perspective view of an exemplary clamping mechanism in three different states;

[0020] Fig. 9 is an exemplary weight and Figure 8 A perspective view of the clamping mechanism shown in Figure 2 in combination with a cableway component;

[0021] Fig.10 shows a perspective view of a weight clamping mechanism in two different states;

[0022] Fig.11 yes Figure 7 a perspective view of a weight with a clamping mechanism in the illustrated station; and

[0023] Figure 12a-12c Yes Figure 7 Three alternative simplified electrical connection diagrams for a station are shown.

[0024] All figures share reference numerals for identical or corresponding parts. DETAILED DESCRIPTION

[0025] thus, Figure 1 A system 100 according to the invention is shown, which is particularly suitable for storing energy in the form of gravitational potential energy and is particularly suitable for performing the method according to the invention. The basic principle used by the invention embodied by the system 100 and method described herein is to use electrical energy to lift a plurality of weights 140 from a low position (a first station 110 described below) to a high position (a second station 120), and then generate electrical energy when lowering the lifted weights 140 again. This lifting and lowering is carried out using a cableway 130, which is similar to a conventional cableway for transporting people, but is particularly suitable for the situation to be described below.

[0026] exist Figure 1 20 represents the ground, and the cableway 130 extends along the contour of the ground between the stations 110 and 120. However, it can be appreciated that the present invention can be implemented in any location where there is a height difference between these locations, where the stations 110 and 120 can be arranged between these locations, and where the cableway 130 of the current type exists between the stations.

[0027] Thus, the system 100 includes a plurality of weights 140; a first station 110 at a lower level; and a second station 120 at an upper level. The lower station 110 may be arranged at a position at least 20 meters lower than the upper station 120, illustratively, at least 50 meters lower (e.g., measured from the drive wheel of the cableway 130 to the drive wheel of the cableway 130). In other words, when the weights are transported from the first station 110 to the second station 120, the center of mass of each weight 140 rises by at least 20 meters, e.g., at least 50 meters.

[0028] Each station 110 , 120 is arranged to receive and hold a weight 140 .

[0029] As mentioned above, the system 100 further comprises a cableway 130 arranged to transport a heavy object 140 to and fro between the first station 110 and the second station 120 .

[0030] To achieve this, the cableway 130 includes a transmission cable 131, which itself may be a conventional, suitably sized steel cable, for example. The transmission cable 131 extends between and is supported by support posts 134, which themselves may be conventional cableway support posts, including wheels, over which the transmission cable 131 moves and over which it passes.

[0031] The cableway 130 further includes an electric motor 132 and a generator 133 . Figure 6 A situation is shown in which the motor 132 and the generator 133 are the same device, which acts as a motor when inputting power into the system 100 by agitating the transmission cable 131, and acts as a generator when extracting power from the system 100 by driving the transmission cable 131.

[0032] However, as appropriate, the system 100 may alternatively include a single motor 132 and a single generator 133. The first site 110 may also include multiple motors 132 and / or multiple generators 133, which may be the same or different devices. In some cases, the second site 120 may correspondingly include multiple motors 132 and / or multiple generators 133, which may be pairs of the same or different devices. If any of the sites 110, 120 includes more than one motor 132 and / or generator 133, they may be arranged to work in series or in parallel with each other in such sites 110, 120.

[0033] The or each motor 132 may be a direct current (DC) motor, an alternating current (AC) motor or an asynchronous AC motor. Similarly, the or each generator 133 may be a direct current (DC) generator, an alternating current (AC) generator or an asynchronous AC generator.

[0034] It is to be understood that the system 100 may include more than two stations 110, 120, such as one or more intermediate stations having similar configurations.

[0035] In particular, the system 100 may be connected to a power grid 10 , such as a municipal power grid. In this case, preferably, the motor 132 and / or the generator 133 are provided in the station 110 , 120 , which is arranged to be connected to an electrical connection point of the power grid 10 .

[0036] Further, the system 100 may include a battery 170 connected to the cableway 130, in particular to the motor 132 and the generator 133. There may be a gear mechanism between the motor / generator 132 / 133 and the main drive / generator wheel of the cableway 130 for achieving a desired rotation speed of the motor / generator 132 / 133. The battery 170 is then arranged to receive electrical energy from the cableway 130 and to provide electrical energy to the cableway 130 via said connection. The battery 170 may also be arranged to receive electrical energy from and to provide electrical energy to said power grid 10. By lifting and lowering the weight 140 and the corresponding actions of the motor 132 and the generator 133, electrical energy can be loaded into and taken from the system 100 relatively quickly. Even in Figure 1 and 2 In the embodiment, the battery 170 is shown as being connected in series between the station 110 and the grid 10. It can be appreciated that in practical applications, the battery 170 can also be connected in parallel (e.g. Figure 12a-12c shown).

[0037] like Fig.12a As shown, the station 110 (and / or 120, as the case may be) may be connected in series to a transformer 172 and then to the grid 10. A battery 170 may be connected in parallel therewith, for example between the station 110 and the transformer 172, and further connected in series with an inverter 171 connected between the battery 170 and the station 110 and / or the transformer 172. This applies to the case where the generator 133 is an AC generator.

[0038] If the generator 133 is a DC generator and the operating voltage range of the battery 170 matches (eg, overlaps or is the same as) the output voltage range of the generator 133, then Figure 12b The arrangement shown, in which the battery 170 is connected in parallel between the station 110 and the inverter 171. In this case, the transformer 172 can be connected in series between the inverter 171 and the grid 10.

[0039] exist Fig.12cIn the third example shown, the generator 133 is a DC generator, but does not match the voltage of the battery 170. In this case, a DC / DC transformer 173 connected between the battery 170 and the station 110 and / or the inverter 171 is added.

[0040] exist Figure 12a-12c In all cases, the battery 170 may be arranged with a control function for switching the charging / discharging of the battery 170 on / off (eg under the control of the control device 180).

[0041] In a preferred embodiment, the station 110 includes a DC generator arranged to provide a voltage at its output terminal that is close to the voltage of the battery 170, in a sense that the battery 170 can directly receive this voltage for charging. In this case, the same inverter 171 can be used to provide a DC voltage to the battery 170 and an AC voltage to the grid 10.

[0042] In other embodiments, the voltage produced by the generator is variable due to a controlled loading of the ropeway 130 and / or a change in the speed of the ropeway 130 .

[0043] It is even possible to use cableway 130 as a frequency regulation component of grid 10, in the sense that the flow of electrical energy into and out of system 100 can be regulated on a relatively short time scale. Such regulation can be performed by speeding up and slowing down transmission cables 131, which can be done very quickly and involves relatively high powers.

[0044] However, in some use cases, the battery 170 may provide even faster power regulation in and out of the system 100 and may allow for greater instantaneous power flow in and out of the system 100. Figure 1 As shown, the battery 170 may preferably be connected in parallel between the cableway 130 and the grid 10 .

[0045] The weight 140 is arranged to be attached to the transmission cable 131 at the first station 110, and then transported upward to the second station 120 by its attachment to the transmission cable 131. To achieve this, the cableway 130 is arranged to transport a plurality of weights 140 by converting available electrical energy into the gravitational potential energy of the weights 140 when the weights 140 are transported from the first station 110 to the second station 120 by the cableway 130. By accelerating the weights 140 in this process, the electrical energy can first be converted into kinetic energy. Therefore, the motor 132 needs electrical energy to stir the transmission cable 131 of the cableway 130, thereby lifting the weights 140 by pulling the weights 140 along the ground 20 when the transmission cable 131 moves. When the weights 140 are lifted to the second station 120, this energy (e.g., by kinetic energy) is converted into the gravitational potential energy of the weights 140. The required electrical energy may be obtained from the battery 170 and / or the grid 10 .

[0046] In addition, the cableway 130 is arranged to transport a plurality of weights 140 from the second station 120 back to the first station 110 by allowing them to move in the gravitational field. In this way, the gravitational potential energy can be converted into kinetic energy. In summary, the generator 133 is activated to convert potential energy (e.g., through kinetic energy) into electrical energy. Therefore, the weights 140 connected to the transmission cables 131 of the cableway 130 can push the transmission cables 131 to which they are connected by moving in the gravitational field, thereby falling down along the cableway 130 in the direction of the first station 110. The generator 133 is used to convert the potential energy into electrical energy, which is then fed to the battery 170 and / or the power grid 10.

[0047] It will be appreciated that other configurations may be employed, such as using photovoltaic cells to generate electrical energy for driving the motor 132, and using the electrical energy output by the generator 133 to perform some work, such as driving a motor or heating a heat medium.

[0048] Figure 2 The system 100 is shown from above. Here it can be seen that the transmission cable 131 runs in an endless loop from the first station 110 to the second station 120 and back again. In each station 110, 120, it can run around a wheel, such as a conventional cableway drive wheel. An electric motor 132 and / or a generator 133 can be connected to one or more of these wheels for driving / braking. Such wheels can also be equipped with tension increasing devices to provide sufficient tension for the transmission cable 131 during the operation of the cableway 130.

[0049] Figure 3 A method for storing energy in the form of gravitational potential energy is shown, which is performed using system 100 in accordance with the present invention.

[0050] The method starts in a first step S1 .

[0051] In the following step S2, a weight 140 may be provided if it has not already been provided.

[0052] In the subsequent step S3, a plurality of weights 140 are attached to the transmission cables 131 of the cableway 130 at the first station 110. Such attachment between each weight 140 and the transmission cables 131 is preferably temporary, and a detachable coupling mechanism is used between the weights 140 and the transmission cables 131, so that the weights 140 are first attached to the transmission cables 131 at the first station 110 before being sent to the second station 120.

[0053] Once at the second station 120, the weights 140 can be detached again and then later reconnected to the transport cable 131 to be sent back down to the first station 110, where they can be detached again, and so on, traveling back and forth between the first station 110 and the second station 120.

[0054] At each station 110 , 120 , one weight 140 can be attached and detached at a time.

[0055] In a subsequent step S4, the motor 132 is used to convert available electrical energy (available from the battery 170 and / or the power grid 10) into potential energy, for example via the above-mentioned kinetic energy, and the motor 132 converts the available electrical energy into potential energy by transporting the weight 140, for example by accelerating or at least driving the conveying cable 131, and thereby also driving multiple weights 140, along the cableway 130 to which the weights 140 are attached, from the station 110 to the station 120.

[0056] It will be appreciated that the electrical energy provided by the motor 132 enables the weight 140 to be lifted from the first station 110 to the second station 120, regardless of whether the weight 140 is first accelerated and then lifted during the deceleration process; whether it maintains a completely or approximately constant speed along the length of the cableway 130; or whether it is accelerated all the way to the second station 120.

[0057] In the subsequent step S5 , the weights 140 are maintained at the second station 120 , and the system 100 thus stores the gravitational potential energy contained in the mass of each weight 140 previously lifted.

[0058] In a subsequent step S6 (which may be performed later for each weight 140), the gravitational potential energy is again converted back into electrical energy. This is achieved by allowing the weight 140 to move in the gravitational field while being transported along the cableway 130 from the second station 120 to the first station 110, as described above, loading the generator 133. Similarly, the weight 140 may travel along the cableway 130 at an accelerated, constant or substantially constant or decelerated speed as appropriate on the way down to the first station 110. Again, it is important that the gravitational potential energy is converted into electrical energy by the generator 133 and can be provided to the battery 170 and / or the power grid 10.

[0059] The generator 133 can decelerate (or at least limit its acceleration) the transmission cable 131 of the cableway 130 to generate the electrical energy. In other words, the generator 133 is loaded by the weight 140 of the transmission cable 131 to affect the movement of the weight so that the weight does not fall freely along the path of the transmission cable 131.

[0060] It can be further recognized that the energy conversion from electrical energy to kinetic energy, then to potential energy, and then back to kinetic energy and electrical energy can also be described as: due to the load of the mass of the weight 140 on the motor, the electrical energy is directly converted into potential energy; then, the generator is loaded with the mass of the weight 140, and accordingly, the potential energy is directly converted back into electrical energy.

[0061] In the subsequent step S7, the weight 140 can be detached from the conveying cable 131 again for storage in the first station 110 until it is reattached for transport back to the second station 120. It can be appreciated that step S5 can also include such detachment and reattachment operations of the weight 140 in the second station 120.

[0062] In step S8 (which may be performed continuously during the process of lowering the weight 140), the electrical energy provided by the generator 133 may be converted (via the transformer 172 and / or the inverter 171) to adapt to the needs of the consumer of the generated electrical energy (e.g., the battery 170 or the grid 10). For example, such conversion may include modifying the voltage of the output electrical power, and / or conversion from direct current to alternating current, or vice versa.

[0063] The method ends in the following step S9.

[0064] like Figure 3 As shown, the method can be iterative, so that the weight 140 is repeatedly brought to the second station 120 and returned to the first station 110. During this process, the weight 140 can be detached / reattached at any station 110, 120, or it can not be detached / reattached.

[0065] Figure 4 An exemplary weight 140 is shown.

[0066] An important discovery of the present invention is that the weight 140 can be made more compact and therefore has a higher overall density compared to conventional ropeways for transporting people or goods. To this end, the weight 140 is preferably made of concrete and / or metal materials (such as iron or other steel materials). The weight 140 can also be in the form of a water-filled or sand-filled container (such as a plastic container). In other embodiments, the weight 140 can be made of other mineral materials such as stone.

[0067] The weight 140 can also be made of rubber or other elastic materials to increase the robustness during transportation, handling and storage. For example, when adjacent weights 140 are in direct contact, this elastic material can be used as a surface damper between adjacent weights 140.

[0068] One simple method of manufacturing such a weight 140 is to cast such a material. For example, the weight 140 may include 80% or more by weight of a material that is cast to form its shape, such as cast concrete or iron.

[0069] To achieve this, the weights 140 are preferably stackable, in other words, they have a shape that allows them to be together formed into a stack of weights 140. This stacking can be done in the direction and orientation of the weights 140 traveling along the cableway 130, or in other directions / orientations, depending on the design of the weight handling mechanisms 112, 122 (see below).

[0070] It should be noted that conventional ski lift chairs are stackable. However, the weights 140 of the present invention are preferably stackable more closely together. That is, each weight 140 preferably includes a stackable component 141 that can be stacked with corresponding stackable components of other weights 140 to form a stack containing at most 20% air. Therefore, when the stack volume is defined as the outer envelope 145 of the stack 144 of such weights 140 (see Figure 5 ), the stacking volume contains 80% or more of the stackable parts 141 of the weights 140 and less than 20% of air.

[0071] The stackable components 141 may each be solid and may be made of the concrete and / or metal material.

[0072] like Figure 4 As shown, one example of such a stackable component 141 is a corresponding parallelepiped-shaped component, such as a cuboid. However, the stackable components 141 may include various shape details to guide one of the stackable components 141 to combine with its adjacent components to form the stack 144. Such shape details are Figure 5In the stack 144 of weights 140 , a stacking joint 143 is shown.

[0073] It will be appreciated that any such coupling device 143 may be used, including designed protrusions and / or grooves, to form a stack 144 that is both overall compact and capable of limiting lateral relative movement of adjacent weights 140 in at least one direction, depending on how the stacked weights 140 are stored in stations 110, 120.

[0074] Regardless, the weights 140 may be stored in stations 110, 120 in a stacked form, with the stack 144 being arranged in one, two, or three dimensions such that the weights 140 collectively define a vector (line), or a two-dimensional or three-dimensional matrix.

[0075] As mentioned above, Figure 5 An exemplary stack 144 in two dimensions (width W and depth D) is shown, also illustrating how the stacking coupling device 143 provides a compact coupling between the individual weights 140.

[0076] The dimensions (height H, width W, depth D) of the compact weight 140 can be made small enough to make the overall design of the cableway 130 relatively compact. Therefore, the total height H of the weight 140 can allow the weight 140 to protrude downward from the transmission cable 131 by no more than 5 meters, for example, no more than 3 meters when attached to the transmission cable 131. In this way, the support 134 can be made relatively short, thereby achieving the purpose of low cost but strong and durable.

[0077] To increase the mass of each weight 140, the width W and / or the depth D may be increased. In a preferred embodiment, the horizontal cross-section of each weight 140, such as the horizontal cross-section of the corresponding stackable component 141 of the weight 140, may be at least 0.2 square meters, such as at least 0.5 square meters, 1 square meter, such as at least 2 square meters.

[0078] Another advantage provided by the present invention is that a large number of weights 140 may be used simultaneously in the system 100 simply by creating sufficient storage space at the stations 110 , 120 to accommodate weights 140 not currently being transported up or down the cableway 130 .

[0079] Preferably, the number of weights 140 may be at least twice, such as at least five times, or even at least ten times, such as at least one hundred times, such as at least one thousand times, compared to the total number of weights 140 that can be loaded simultaneously along the conveying cables 131 of the cableway 130.

[0080] The weights can be arranged on the transmission cable 131, and the minimum distance between the weights is at most 20 meters, such as at most 10 meters, such as at most 5 meters. The total number of weights 140 used in the system 100 can be at least 200, such as at least 500, such as at least 1000, such as at least 10000.

[0081] In some embodiments, the weights 140 are transported along the transmission cables 131, and adjacent weights 140 are in direct contact along at least a portion of the cableway 130. The stacking and combining device 143 of the above type can combine adjacent weights 140 traveling along the cableway 130, thereby limiting the swing and other unintended movements of the weights 140.

[0082] It should be noted that the weight does not need to include any means for transporting people or goods. Optionally, each weight 140 is intended to fully utilize the density of space allocated to each weight 140 when transported along the cableway 130, especially when stored in the stations 110, 120. Therefore, the weight 140 preferably does not include any seats or any pulling devices for people to sit or stand on skis. At the same time, it is foreseeable that in addition to the weight 140, a limited number of transportation devices for service technicians, equipment, spare parts, etc. can be used in the system 100 and transported back and forth between the stations 110, 120 when such transportation needs arise.

[0083] As mentioned above, the stations 110, 120 are respectively used to store the heavy objects 140 that are not currently being transported along the cableway 130. In particular, the first station 110 and / or the second station 120 can be arranged to store the heavy objects 140 in a state where the heavy objects are disconnected from the conveying cables 131 of the cableway 130. Therefore, when each heavy object 140 arrives at the relevant station 110, 120, it will fall off the conveying cables 131 and be stored in the relevant station 110, 120. Before being transported again, it will be reattached to the conveying cables 131, so that it can start moving along the cableway 130.

[0084] The beneficial effect is that the storage space utilization of the weights 140 is high. To achieve this, the weights 140 can be stacked along a line as described above, preferably in the form of a two-dimensional or three-dimensional grid or matrix.

[0085] Then, these packed or stacked weights 140, as described above, together form the peripheral envelope 145 of the body formed by all the weights 140 stacked together in the stations 110, 120. Then, when the first station 110 and / or the second station 120 store the weights 140, the weights 140 can be arranged to occupy (and at least occasionally actually occupy during operation) at least 50% of the total storage volume defined by the peripheral envelope 145 of the outermost weights 140.

[0086] like Figure 2 and Figure 6 As shown and described herein, at least one of the first station 110 and the second station 120, preferably both stations 110, 120, may include respective storage spaces 111, 121 for the heavy objects 140. Further, the first station 110 and / or the second station 120 may include respective heavy object handling mechanisms 112, 122, which are arranged to automatically disconnect / separate the heavy objects 140 from the conveying cable 131; transport these disconnected heavy objects 140 to respective storage locations in the storage spaces 111, 121 for storage; transport the disconnected heavy objects 140 back to the conveying cable 131; and reattach the disconnected heavy objects 140 to the conveying cable 131 for transport along the cableway 130.

[0087] The heavy object handling mechanism 112, 122 itself can be a conventional automated storage robot, which is arranged to attach individual heavy objects 140 and move them in the storage spaces 111, 121. The heavy object handling mechanism 112, 122 can include a bridge crane, which is arranged to lift and horizontally move the heavy objects 140; a wheeled trolley system, which is arranged to support and horizontally move the heavy objects 140; a track system, which is arranged to support and horizontally move the heavy objects 140, and the like.

[0088] Since the weights 140 may be identical, the storage bin may be a FILO (first in, last out) storage bin. In some embodiments, the storage bin includes at least two weights 140 of different masses, and the weight handling mechanisms 112, 122 include a selection device to select the weight for attachment and transportation according to the current total power demand of the system 100. Alternatively or in addition, the weights 140 may also be attached to the conveying cable 131 at different length intervals of the conveying cable 131. Alternatively or in addition, the proportion of the clamping devices 150 (see below) attached to the conveying cable 131 and transported thereby that actually clamp each weight 140 may also be changed (relative to the case of air transport along the cableway 130 without clamping the weights 140).

[0089] The system 100 may include a control device 180, which is arranged to communicate with the weight handling mechanism 112, 122 and the cableway 130, so as to realize automatic handling of the weight 140 in the system 100. Therefore, the control device 180 may be arranged to control the cableway 130 to move the transmission cable 131 attached with the weight 140 to the second station 120; control the weight handling mechanism 122 of the second station 120 to separate the weight 140 and move the weight 140 to the storage space 121 of the second station 120 for storage; control the weight handling mechanism 122 of the second station 120 to move the weight 140 to the transmission cable 131 again and attach the weight 140 to the transmission cable 131 On; control the ropeway 130 to move the conveying cable 131 attached with the weight 140 to the first station 110; control the weight handling mechanism 112 of the first station 110 to separate the weight 140, and move the weight 140 to the storage space 111 of the first station 110 for storage; control the weight handling mechanism 112 of the first station 110 to move the weight 140 to the conveying cable 131 again, and attach the weight 140 to the conveying cable 131; and so on.

[0090] In some embodiments, the storage spaces 111, 121 in one or both stations 110, 120 are vertical storage spaces arranged to store heavy objects 140 in multiple layers 117, 127. To achieve this, the heavy object handling mechanisms 112, 122 may include heavy object 140 lifting devices, such as elevators or crane devices.

[0091] like Figure 6 As shown, the first station 110 and / or the second station 120 may include respective weight deceleration mechanisms 115, 125. The weight deceleration mechanisms 115, 125 may be used to decelerate the weight 140 transported to the stations 110, 120 to a speed that the weight handling mechanisms 112, 122 can handle when receiving and separating the weight 140, as described above. This deceleration may be performed in any of the following ways after the relevant weight 140 is separated from the conveying cable 131, and before the weight 140 reaches the weight handling mechanisms 112, 122.

[0092] The weight deceleration mechanism 115, 125 may include a local uphill portion 116, 126, such as a small bump through which the weight 140 passes. The local uphill portion 116, 126 may include a local bend in the path along which the weight 140 travels, such as a fixed wheel channel, and the weight 140 travels by wheels rolling on the channel. The local uphill portion 116, 126 may be arranged to locally lift the weight 140 when the weight passes through the uphill portion 116, 126.

[0093] Furthermore, uphill portions 116, 126 may be arranged to slow down weight 140 using only the increased gravitational potential energy of weight 140 as a deceleration means. In other words, in some embodiments, weight deceleration mechanisms 115, 125 include frictionless brakes, magnetic brakes, or the like.

[0094] In some embodiments, the weight 140 passing through the weight deceleration mechanism 115, 125 is decelerated to a speed of at most 2 m / s, such as at most 1 m / s, or even decelerated to a standstill or near standstill.

[0095] A corresponding weight acceleration mechanism 119 may be provided for accelerating the weight 140 before it reaches the conveying cable 131 for attachment thereto, for example through a downhill section. Figure 7 This is an example of such a situation. Such a downhill section can be selected with a height difference so that the weight 140 reaches the speed of the transmission cable 131 when the clamping device 150 (with or without the weight 140) reaches the transmission cable 131 and attaches to it. As in the case of the weight deceleration mechanism 115, the weight acceleration mechanism 119 can also be adjusted, for example by changing the height difference of the downhill section.

[0096] In some embodiments, the weight 140 handled by the weight handling mechanisms 112, 122 is typically maintained at a height that is higher than the height of the weight 140 when it is separated and attached to the conveying cable 131, and the height difference corresponds to the height difference of the uphill / downhill portion of the weight deceleration mechanism 115 and / or the weight acceleration mechanism 119.

[0097] In these and other embodiments, the weight 140 travels along the cableway 130 at a speed (e.g., constant speed) of at least 5 m / s, such as at least 10 m / s. However, it is contemplated that the instantaneous input / output power of the system 100 may be adjusted by at least one of the first control device and the second control device, the first control device controlling the total net number of weights 140 transported upward or downward at any instant; and the second control device controlling the transport speed of the cableway 130 at any instant. Therefore, the speed at which the weight 140 arrives at the weight reduction mechanism 115, 125 may vary.

[0098] It is preferred that the weights 140 arrive at the weight handling mechanisms 112, 122 at a constant speed. For one reason or another, the uphill sections 116, 126 may be adjustable so that the total distance that the weights 140 are lifted as they pass through the uphill sections 116, 126 may be adjusted according to the speed at which the weights 140 enter the uphill sections 116, 126. The control device 180 may be arranged to control the weight deceleration mechanisms 115, 125 so that a predetermined arrival speed of the weights 140 is achieved at the weight handling mechanisms 112, 122 according to the currently controlled transport speed of the cableway 130. It will be appreciated that the speed at which each weight 140 arrives at the weight deceleration mechanism generally depends on the travel speed of the conveying cable 131.

[0099] The weight acceleration mechanism 119 (if used) can be controlled by the control device 180 in a corresponding control manner to the weight deceleration mechanisms 115, 125.

[0100] It is generally preferred that the system 100 includes a plurality of clamping devices 150 for removably fixing the weight 140 on the transmission cable 131. It is understood that, as an alternative to using such clamping devices 150, a longer transmission cable 131 can be used, which can be drawn out in the storage space 111, 121 according to the desired storage mode corresponding to the weight 140. However, the use of removable clamping devices 150 has greater flexibility in terms of storage efficiency, scalability, and power control of the system 100.

[0101] Reference Figure 7-11 , Figure 7-11 An exemplary station 110 or 120 is shown, along with a plurality of processed weights 140. It should be noted that Figure 7-11 The illustrated workstations 1 110 and 120 are simplified for the purpose of clearly illustrating the principles described herein.

[0102] exist Figure 7 , a motor / generator wheel is shown, together with a conveying cable 131, a separation device 118 for separating a single weight 140 from the conveying cable at the end of the ropeway 130 and reattaching the single weight 14 to the conveying cable for handling by a weight handling mechanism 112. Figure 7 The heavy object handling mechanism 112 is labeled but not shown in detail. For example, it can include a conventional programmable industrial robot including an arm with a gripping device for gripping and moving the heavy object 140. The heavy object 140 can be transported on a cable, on a moving floor, or in any other suitable manner.

[0103] like Figure 8As shown, each of the clamping mechanisms 151 of the clamping devices 150 can be spring loaded in two different directions 153, 154, away from the unstable state ( Figure 8 The clamping mechanism 151 is moved to a fixed and stable combination state with the transmission cable 131 ( Figure 8 ), and moves the clamping mechanism 151 in another direction to a stable static state (not combined with the transmission cable 131) Figure 8 Right) (Transmission cable holder open).

[0104] To this end, the clamping mechanism 151 includes at least one (e.g., two) springs 152 and a lever 155. The lever 155 is spring-loaded in the unstable state (a pivot position between a stable locking pivot position and a different stable unlocking pivot position). In other words, the lever 155 is loaded by the spring force of the spring 152 from Figure 8 The locked state shown on the left is Figure 8 Once the unstable point is passed, the spring 151 will further push the lever 155 to reach a stable open or unlocked state, such as Figure 8 As shown in the right figure, the lever can move from a stable unlocking state to an unstable state under the force of the spring 151, and then further move to a stable clamping or locking state under the push of the spring 151.

[0105] The lever 155 may include a control wheel 156 that engages with a fixed wheel track 157 of the separation device 118 to move the lever 155 (and thereby the clamping mechanism 151) into and out of the locked / unlocked state. Fig. 9 This is explained.

[0106] Thus, each clamping mechanism 151 is arranged to removably secure a single weight 140 to the conveying cable 131 for transport between the stations 110, 120. Each clamping device 150 may include two mating engagement components, one disposed on the weight 140; the other disposed on the conveying cable 131, or when the weight 140 is to be secured to the conveying cable 131, arranged to be secured to the conveying cable 131. When the mating engagement components are engaged, the weight 140 is removably secured to the conveying cable 131 by such engagement for transport along the cableway 130. It is understood that the clamping mechanism 151 may constitute one of the two mating engagement components, and the clamping device 150 is constituted by two mating engagement components.

[0107] Generally, each clamping device 150 may include an active / actuable (clamping) component and a passive (clamped) component. The clamped component may be a steel ring, a cast shape feature, or any other suitable shape to combine with an actuatable mating engagement component.

[0108] Preferably, the active / clamping mechanism components can be separated from the weights 140, and the passive / clamped mechanism components are arranged as a part of each weight 140. In this way, the design of the weights 140 is more concise and can better resist ice formation in cold seasons. In addition, the number of the clamping mechanisms of the movable parts can also be less than the total number of weights 140.

[0109] In some embodiments, each clamping mechanism 151 (active / clamping component) is attached to the transmission cable 131, for example, permanently attached to the transmission cable 131, and moves with the transmission cable 131. In other embodiments, the clamping mechanism 151 (active / clamping component) is arranged to be detachably fixed to the transmission cable 131 when used to attach and fix the respective weight 140 to the transmission cable 131, and is stored in one of the stations 110, 120 (such as when the weight 140 is not fixed). Figure 6 As shown). It will be appreciated that the weight handling mechanisms 112, 122 can handle the clamping mechanisms 151 in a manner corresponding to the handling of the weights 140 in the stations 110, 120 described above. The method may include sending such clamping mechanisms 151 without corresponding weights 140 along the cableway between the stations 110, 120 in case the number of such clamping mechanisms 151 needs to be balanced.

[0110] exist Figure 4 In FIG. 1 , a weight 140 is shown having a passive (clamped) component 142 arranged on the weight 140 in the form of a hook that can be clamped by an active (clamping) component.

[0111] exist Fig.10 A more detailed example is shown in FIG. 1. The weight 140 has a passive (clamped) fastening device 142, while the clamping device 150 has an active (clamping) fastening device 123 in the form of an attachment / detachment mechanism of the weight 140. The fastening devices 123 and 142 cooperate with each other by being coupled to each other.

[0112] The attachment / detachment mechanism of the weight 140 includes a spring 123a, a wheel 123b ( Fig.11 ), resisting the elastic force of the spring 123a to actuate (e.g., compress) the spring 123a, thereby disengaging the clamp 123d from the fastening device 142, and the weight 140 is thus disengaged from the clamping device 150 ( Fig.10, below). 123e represents a wheel for applying a reaction force when pushing against a rigid support (not shown). When the wheel 123b is allowed to move backward under the push of the spring 123a, the clamp 123d is again engaged with the fastening device 142, thereby fixing the weight 140 on the clamping device 150 ( Fig.10 , above).

[0113] Thus, the gripping device 150 may include one or both of a fastening device arranged to be fixed to the transmission cable 131 and a fastening device arranged to be fixed to the weight 140. These fastening devices may be independently actuated, for example using the above-mentioned different fixed wheel rails. The weight 140 may be fixed to the transmission cable 131 using the gripping device 150 so as to be transported between the stations 110 and 120, or the weight 140 may be removed from the transmission cable 131 so as to be stored at any position of the stations 110 and 120. This provides good flexibility in the handling of the weight 140 and the gripping device 150 in the system 100.

[0114] like Fig.10 As shown, the clamping device 150 may include a counterweight 158 ​​arranged so that the clamping device 150 can be hung straight enough on the transmission cable 131 when no weight 140 is attached to the clamping device 150 .

[0115] In some embodiments, the clamping mechanism 151 is arranged to be heatable, such as electrically heated. For example, each clamping mechanism 151 can be provided with a heating coil arranged to be powered by an electrical connection with the heavy object handling mechanism 112, 122 when stored in the station 110, 120. Therefore, each clamping mechanism 151 can have an electrical connector or interface arranged to receive an electric current and circulate it in the clamping mechanism 151. In some embodiments, the clamping mechanism 151 is heated when it is stored and / or handled at rest in the station 110, 120, but may not be heated when it is moved by the cableway 130.

[0116] like Fig.11As shown, the clamping mechanism 151 may include two pairs of transport wheels 159, one pair of which is arranged to support the clamping mechanism 151 (and possibly the weight 140 carried) on the lower part of the fixed wheel track 160, and the other pair of which is arranged to roll or slide against the upper part of the fixed wheel track 160. The lower and upper parts of the wheel track 160 can extend along a section of the wheel track 160, which is arranged to transport the weight 140 when the conveying cable 131 is not attached or the clamping device 150 without clamping any weight 140. In this way, when the weight 140 is separated and reconnected relative to the conveying cable 131 and / or relative to the clamping device 150, stability can be increased because the weight 140 can be prevented from swinging around an axis parallel to the conveying track of the weight 140 pulled by the transport wheels 159.

[0117] As shown, as described above, the transmission cable 131 may be an endless cable driven by at least one drive wheel of one of the stations 110, 120. In this case, the cableway 130 may be arranged to be driven in a first direction D1 (which direction refers to the driving direction of one of the two parts of the endless transmission cable 131) so as to transport the weight 140 from the first station 110 to the second station 120, and to transport the weight 140 from the second station 120 to the first station 110 in a second opposite direction D2. Alternatively, the cableway 130 may be arranged to be driven in the same direction D1 or D2 so as to transport the weight 140 from the first station 110 to the second station 120, and to transport the weight 140 from the second station 120 to the first station 110. In some embodiments, these two operating modes may be combined, so that the control device 180 can drive the cableway in either direction D1, D2, and attach or detach the weight 140 to any of the two parallel parts of the transmission cable 131 forming the endless loop. This may allow for more flexible operation, with shorter settling times when adjusting the total instantaneous power of the system 100 .

[0118] The above description is of a preferred embodiment. However, it is obvious to a skilled person that many modifications may be made to the disclosed embodiments without departing from the basic concept of the present invention.

[0119] For example, weight 140 may be designed in a variety of different ways, and system 100 may be used in a variety of different types of geographies.

[0120] For the sake of comfort and safety, ropeways used to transport people or goods usually need to limit the acceleration during transportation, so such high-end ropeways are usually equipped with quite complex devices for disconnecting the transported objects from a separate transmission chain, which has a lower speed than the main transmission cable. In the present solution, such a disconnection device is not required because the weight 140 can be designed to be strong enough to withstand quite high accelerations.

[0121] All discussions regarding the present method are also applicable to the present system, and vice versa.

[0122] The invention is thus not limited to the described embodiments but it may be varied within the scope of the attached claims.

Claims

1. A system (100) for storing energy in the form of gravitational potential energy, the system (100) comprising: a plurality of weights (140); a first lower station (110) arranged to receive and hold a weight (140), and a second upper station (120) arranged to receive and hold a weight (140); a cableway (130) arranged to transport a weight (140) back and forth between the first station (110) and the second station (120), the cableway (130) comprising a conveying cable (131), an electric motor (132) and a generator (133), the weight (140) being arranged to be attached to the conveying cable (131) at the first station (110), The cableway (130) is arranged to activate the motor (132) to transport a plurality of the weights (140) by converting available electrical energy into gravitational potential energy of the weights (140) when the weights (140) are transported by the cableway (130) along the ground (20) from the first station (110) to the second station (120); The cableway (130) is arranged to transport the plurality of weights (140) from the second station (120) to the first station (110) by gravity in a gravity field, and activate the generator (133) to convert the potential energy into electrical energy.

2. The system (100) according to claim 1, wherein The generator (133) and the motor (132) are the same device.

3. The system (100) according to claim 1 or 2, wherein The weight (140) is made of concrete and / or metal material, such as iron or steel.

4. The system (100) according to claim 3, wherein At least 80% of the weight of the weight (140) is composed of cast material.

5. The system (100) according to any one of the preceding claims, wherein Each of the weights (140) comprises a stackable component (141), such as a corresponding parallelepiped-shaped component, which is arranged to be stacked together with corresponding stackable components of other weights (140) to form a stack containing at most 20% air.

6. The system (100) of claim 5, wherein The stackable component (141) is made of solid material.

7. The system (100) according to any one of the preceding claims, wherein The weight (140) when attached to the transmission cable (131) protrudes downward from the transmission cable (131) by no more than 5 meters.

8. The system (100) according to any one of the preceding claims, wherein The number of the weights (140) is at least twice the total number of weights (140) that can be simultaneously accommodated by the transmission cables (131) along the ropeway (130), for example, at least five times, or even at least ten times.

9. The system (100) according to any one of the preceding claims, wherein The weight (140) does not include any seat or traction device for a person to sit or stand on the snowboard.

10. The system (100) according to any one of the preceding claims, wherein The first station (110) and / or the second station (120) is used to store a heavy object (140) disconnected from a conveying cable (131) of the cableway (130).

11. The system (100) of claim 10, wherein When the weights (140) are stored at the first station (110) and / or the second station (120), the weights (140) are arranged to occupy at least 50% of the total storage volume defined by the outer envelope surface of the outermost weights (140).

12. The system (100) according to any one of the preceding claims, wherein The first station (110) and / or the second station (120) further include respective storage spaces (111, 121) and respective weight handling mechanisms (112, 122), wherein the weight handling mechanisms (112, 122) are used to disconnect the weight (140) from the conveying cable (131), transport the disconnected weight (140) to a corresponding position in the storage spaces (112, 122), transport the disconnected weight (140) back to the conveying cable (131), and reconnect the disconnected weight (140) to the conveying cable (131).

13. The system (100) of claim 12, wherein The storage space (111, 121) is a vertical storage space for storing heavy objects (140) in multiple layers (117, 127).

14. The system (100) according to any one of the preceding claims, wherein The first station (110) and / or the second station (120) includes a weight deceleration mechanism (115, 125), and the weight deceleration mechanism (115, 125) includes a local uphill portion (116, 126). When the weight (140) passes through the uphill portion (116, 126), the uphill portion (116, 126) is used to lift the weight (140). The uphill portion (116, 126) is arranged to use only the increased gravitational potential energy of the weight (140) as a deceleration mechanism to slow down the speed of the weight (140) to a maximum of 1 meter per second.

15. The system (100) of claim 14, wherein The uphill portion (116, 126) is adjustable so that the total distance the weight (140) is lifted when passing through the uphill portion (116, 126) can be adjusted according to the entry speed of the weight (140) toward the uphill portion (116, 126).

16. The system (100) according to any one of the preceding claims, wherein The system (100) comprises a plurality of clamping devices (150) arranged on a single weight (140) and / or a transmission cable (131) for removably fastening the weight (140) to the transmission cable (131).

17. The system (100) of claim 16, wherein The respective clamping mechanism (151) of each clamping device (150) is spring-loaded in two different directions away from an unstable state, so that the clamping mechanism (151) moves to a stable combination with the transmission cable (131), and moves the clamping mechanism (151) in another direction to a stable standby state not combined with the transmission cable (131).

18. The system (100) according to claim 16 or 17, wherein Each of the clamping mechanisms (151) is attached to the conveying cable (131) and moves with the conveying cable (131).

19. The system (100) of claim 18, wherein The clamping mechanism (151) is arranged to be heatable.

20. The system (100) according to any one of the preceding claims, wherein The electric motor (132) is a DC motor, an AC motor or an asynchronous AC motor, and / or The generator (133) is a DC generator, an AC generator or an asynchronous AC generator.

21. The system (100) according to any one of the preceding claims, wherein The cableway (130) is arranged to be driven in a first direction (D1) to transport the weight (140) from the first station (110) to the second station (120), and to be driven in a second direction (D2) to transport the weight (140) from the second station (120) to the first station (110), and / or The conveying cable (131) is a looped cable, and the ropeway (130) is arranged to be driven in the same direction to transport the weight (140) from the first station (110) to the second station (120), and to transport the weight (140) from the second station (120) to the first station (110).

22. The system (100) according to any one of the preceding claims, wherein The system (100) is connected to a power grid (10), wherein The system (100) includes a battery (170) connected to the cableway (130), the battery (170) being used to receive electric energy from the cableway (130) and to provide electric energy to the cableway (130), and the battery (170) being further used to receive electric energy from the power grid (10) and to provide electric energy to the power grid (10).

23. A method for storing energy in the form of gravitational potential energy, the method comprising: A first providing step of providing a plurality of weights (140), wherein the plurality of weights (140) are attached to a transmission cable (131) of a cableway (130) at a first station (110); a first energy conversion step, using a motor (132) to convert available electrical energy into potential energy by moving a plurality of said weights (140), said weights (140) being transported along the cableway (130) along the ground (20) from the first station (110) to a second station (120), said second station (120) being located higher than the first station (110), said cableway (130) being driven by said motor (132) and transporting said weights (140) from the first station (110) to the second station (120); an energy storage step, wherein the weight (140) is maintained at the second station (120); as well as The second energy conversion step converts the gravitational potential energy into electrical energy by allowing the weight (140) to move in the gravitational field, and when the weight (140) is transported from the second station (120) to the first station (110) along the cableway (130), the potential energy is converted into electrical energy using a generator (133) loaded by the weight (140).

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