AU2020202830B2

AU2020202830B2 - Bi-directional Heavy Mass Energy Storage System

Info

Publication number: AU2020202830B2
Application number: AU2020202830A
Authority: AU
Inventors: Dan Xiao; Daming Zhang
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-04-29
Filing date: 2020-04-29
Publication date: 2022-02-17
Anticipated expiration: 2040-04-29
Also published as: AU2020202830A1

Abstract

Bi-directional Heavy Mass Energy Storage System Abstract This invention relates to a cost-effective, environment-friendly and long-lasting massive energy storage system. It is based on the conversion between potential energy in heavy masses and electricity when containers with heavy masses are moved between low and high platforms. This technology can more quickly lift up containers with heavy masses to cope with the intermittency of renewable energy generation through bi directional movements of multiple mini-locomotives, each of which moves along each of multiple tracks. The containers with heavy masses can be lowered down by the same system or by other high-efficiency system. 2/5 504260 261 two saaJ7~~2 01 201 600 LD 260 261 50341 502 2701 20201 270D201 400EB 5041 I3 L T I ~L I211 33 ~p II 413 -415 41 I I I I 50 to 50 260 261 40DB

Description

2/5

504260 261

two

saaJ7~~2 01 201

600

LD

260 261

50341 502

2701

20201 270D201

400EB

5041

LT I3 I

~L I211 33 ~p II

41 I 413 -415 I I I 50 to 50

260 261 40DB

Field of invention

[001] This invention relates to a cost-effective, environment-friendly and long-lasting massive energy storage system. It is based on the conversion between potential energy in heavy masses and electricity when containers with masses are moved between low and high platforms.

Background

[002] Energy crisis has been an issue after nearly one-hundred-year of use of fossil fuels which will run out very soon within this century. Nuclear fusion could be a high-tech solution but its commercialization is not foreseeable. Grid-scale massive storage is currently in high expectations. When striving for such massive energy storage solution, many limiting factors need be considered such as key materials availability. In the previous work done by the inventor, Daming Zhang, "Issues on Heavy Mass Energy Storage with Vertical Movement by Linear Machine", published in 9th International Conference on Power and Energy Systems (ICPES 2019) at Perth from 10-12 December, a vast amount of permeable and stainless steels need be used, though they are recyclable but massive or global-wide implementation may not be feasible. In another method developed by Daming Zhang, "Heavy Mass Energy Storage with Magnetic Levitated Wheels, Bearings and Locomotive", Journal of Multidisciplinary Engineering Science and Technology (JMEST), ISSN: 2458-9403, Vol. 6 Issue 7, July 2019, the author proposed to use cost-effective method to lift up and lower down containers with heavy masses using locomotive moving along its track which is stationed at the top surface linked with high platforms of the storage system. The chassis or base or container holder, where containers sit, moves vertically along guiding poles through bearings installed on the chassis. A belt is adopted to join chassis and locomotive. At the turning corner between vertical and horizontal belt passage, distributed cylindrical supports are used to reduce pressure force on them thereby reducing friction losses. If magnetic levitation is adopted in each of the cylindrical supports, then friction losses are further reduced. But such system is uni-directional and after the containers are lifted up from low to high platforms, empty base or container holder is lowered down. As the wind is intermittent, moving the containers more quickly from low to high platforms is really necessary. This is the motivation of the disclosed technology as described in the following writing.

Brief description of the drawings

[003] Figure 1 Top view of the heavy mass energy storage system with multiple tracks and locomotives at the top surface linked with high platforms;

[004] Figure 2 Top view (top figure) and vertical cross sectional view (bottom figure) of the heavy mass energy storage system;

[005] Figure 3 Vertical cross sectional view of the locomotive, wheels, tracks, belt, belt guides and their supports;

[006] Figure 4 Force acting on cylindrical support at the corner where belt turns;

[007] Figure 5 Vertical cross sectional view of bottom parking lot or platform, its roof cover and water drainage system;

[008] Figure 6 Top view (top figure) and side view (bottom figure) of the container base or holder;

[009] Figure 7 Top view of a new heavy mass energy storage system with a combination of low-efficiency yet fast driving locomotive based system and high efficiency vertical machine system.

Detailed description

[0010] Figure 1 shows the top view of a heavy mass energy storage system, where there are multiple rail tracks 270 at the top surface in Fig. 2, which is reinforced by steel-reinforced concretes 502,503 and 504 at both sides spreading from low or bottom to high platforms. Each rail track 270 sits an electric locomotive 300 in Fig. 2. Each locomotive 300 is bonded with thin steel or other material belts 201 at each end. Belt 201 is guided by bearings 210 installed on supports which stand on two sides of each rail track 270. At the turning point between vertical and horizontal passage of the belts 201, distributed support surfaces 230,231,232 and 233 are used. Such structure effectively reduces pressure on each of the support surfaces thereby reducing friction losses. Magnetic levitation as described in the paper Daming Zhang, "Heavy Mass Energy Storage with Magnetic Levitated Wheels, Bearings and Locomotive", Journal of Multidisciplinary Engineering Science and Technology (JMEST), ISSN: 2458-9403, Vol. 6 Issue 7, July - 2019 or other structures can be adopted for the distributed support surfaces 231,232 and 233 at both ends of the horizontal rail tracks 270 along which locomotives 300 move.

[0011] The cross sectional view of the locomotive 300, belt 201 and belt guide through bearings 210A and 210B and supports 211A, 211B, 213A, and 213B sitting on stands 212A and 212B is shown in Fig. 3, where wheels 304A and 304B of the locomotive 300 sits on the tracks 303A and 303B. The interfacing part 302 joins belt 201 with locomotive 300. Teeth can be installed along the belt 201 and also on surfaces of rotating distributed supports 231,232 and 233.

[0012] Figure 4 shows the diagram of forces acting on the belt and on the magnetic levitated wheel. Under steady-state movement, the dragging force provided by the locomotive is the same as the weight of the uplifted system, which includes the containers with heavy masses, part or complete of belt and the containers' holder.

[0013] To reduce the friction losses, it is necessary to produce sufficient levitation force, which is calculated by the following expression:

1 = 2Fcosa = 2Fx cos 180°-0 2F. sin( /2)

[0014] Then the required magnetic levitation force divided by weight of the heavy mass is given by

Factor==2 sin(9 / 2) (2) F

[0015] Table I shows 1) the ratio of the levitation force to the weight of heavy mass and corresponding number of support cylindrical surfaces or wheels with different angle 0. 2) the required number of wheels for each angle 0. From Table 1 one can see that the required magnetic levitation force by each wheel is around 26% weight of the uplifted system if 6 wheels are used.

TABLE L FACTOR AND WHEEL NUMBER AGAINST ANGLE

Number of Angle Factor cylindrical

0 wheels

50 0.0872 18 6° 0.1047 15 9° 0.1569 10 10° 0.1743 9 15° 0.2611 6 30° 0.5176 3 45° 0.7654 2 900 1.4142 1

[0016] When there are renewable generations, either from wind or from sunshine, containers with heavy masses, such as fragmented stones are lifted from low platforms to high platforms by the electric locomotive 300. When the container base or holder 400A in Fig. 2 with containers at left side reaches the top of its passage, the base or holder 400B without containers at right side reaches the bottom of the passage. Then locomotive 300 stops for a short time during which the containers sitting on the base or holder 400A which reaches the top of vertical passage is moved by robot arms to tracks 260, along which the containers are moved horizontally to high parking lot or platform by a mini-locomotive. In the meantime, containers with heavy masses are put onto the base 400B on right side which stations at the bottom of the vertical passage linked with low platform. Next locomotive 300 moves in opposite direction and lift up the containers sitting on the base or holder 400B which is pulled by the belt 201 and moves along the vertical passage at right side. Then locomotive 300 stops for a short time during which the containers sitting on the base or holder 400B which reaches the top of vertical passage is moved by robot arms to tracks 261, along which the containers are moved horizontally to high parking lot or platform by a mini-locomotive. In the meantime, containers with heavy masses are put onto the base 400A on left side which stations at the bottom of the vertical passage linked with low platform. In both movements, either from left to right or from right to left on the rail track 270, the electric machine in the locomotive 300 works in motoring mode. By doing so, electricity converted from wind and/or solar can be transformed into potential energy stored in heavy masses in the container sitting on the top platforms.

[0017] Each locomotive on each of the multiple tracks works in the same way as described above.

[0018] Each container is made of steel-reinforced plastics or other materials. During movement, shaking etc is unavoidable. A steel shell can be used to reinforce plastic containers when the container reaches its destination or high platform, steel shell is removed and shifted with container base back to low platform through vertical passage. Multiple such steel shells are manufactured. By doing so, there are no extra waiting time for the locomotive and container bases due to moving the container with masses and shell from the pick-up point to the final destination and returning shared shells back to pick-up point.

[0019] When it is time to convert potential energy into electricity, the containers with heavy masses are lowered down from high platform to low platform. When the base 400A with container reaches the bottom of the vertical passage on the left side, the base 400B without containers reaches the top of its passage on the right side, the locomotive 300 stops. During the stoppage, the containers on the base at the left side are moved by the robot arm to tracks, then moved horizontally to low platform by a separate mini-locomotive. In the meantime, containers with heavy masses are put onto the container base 400B sitting at the top of the passage at the right side. Next the locomotive moves in opposite direction and lowers down the containers with heavy masses sitting on the base or holder 400B along the vertical passage at right side. After the base or holder 400B reaches the bottom of the vertical passage at the right side, locomotive 300 stops for a short time during which the containers sitting on the base or holder 400B is moved by robot arms and further moved horizontally to low parking lot or platform by a mini-locomotive. In the meantime, containers with heavy masses are put onto the base 400A on left side which stations at the top of the vertical passage linked with high platform. In either direction, the electric machine works in generating mode.

[0020] To prevent flooding and sink in the low platforms, roof-like cover needs be built as shown in Fig. 5. Slopes linking to top surfaces with high platform at each side of low platform are adopted. Drainage pump at each side of the low platform is necessary to drain seeping water from neighbouring soil/stone. No matter whether it is the top or bottom platform, steel reinforced concrete foundations are constructed.

[0021] In practice, to save cost, both lifting-up and lowering-down of the containers with heavy masses is done by modified mini locomotive. In the market, there are many types of electric locomotives, some of which can be modified to suit the drive purpose in this system. The basic requirement is that it needs be working in both generating and motoring modes. The AC machine is driven by a converter unit which contains AC/DC converter, DC-link capacitor and DC/AC converter. Both AC/DC converters can work as either rectifier or inverter. By doing so, motoring and generating modes of the machine are facilitated. The machine is mechanically coupled to the bogie frame with wheels moving along rails. Instead of using single-phase AC source in conventional train locomotive drive system, three-phase AC source is adopted here, which is connected with power system formed by renewable generation and other parts.

[0022] Besides AC machine, DC machine could also be used in the system. In such cases, a converter unit which contains AC/DC converter and/or DC/DC converter is used. Bi directional power flow can be achieved.

[0023] If there are sufficient iron ores for producing steel, one may use the machine described in the paper "Energy Buffer and Other Issues in Heavy Mass Energy Storage with Vertical Movement by Linear Machine", Journal of Multidisciplinary Engineering Science and Technology (JMEST), ISSN: 2458-9403, Vol. 6 Issue 6, June - 2019 by Daming Zhang for lowering down containers with heavy masses. Such system works at high efficiency, which can convert the same potential energy into more electricity. Lifting-up of the containers with heavy masses is still fulfilled by the bi-directional movement of locomotive described above. Such combined system can more quickly lift up containers with heavy masses in short time in order to cope with intermittency of renewable energy generation and lower down the containers at higher efficiency. Such combination is shown in Fig. 7.

[0024] Communication needs be adopted to coordinate each part in the whole energy storage system.

Editorial note

2020202830

Claims pages are not numbered. They should be numbered 7 and 8

Claims

The claims defining the invention are as follows:

1. A bi-directional lifting system for a heavy mass energy storage system, which consists of left-hand side container holder and right-side container holder; left-hand side distributed support at the turning point or corner and right-hand side distributed support at the turning point or corner; an electric locomotive sitting on a track on the top of a platform; a belt system joining left-hand side container with right-hand side container holder through the electric locomotive; four poles on each side to guide respective container holder to move along the vertical passage.

2. A method for lifting-up containers with heavy masses and with electric machine in the locomotive working in motoring mode for the system as claimed in claim 1, which consists of the following steps: in the first step, containers with heavy masses at left-side low platform are put onto the container base sitting at low platform and subsequently are lifted up to the top along the left-side vertical passage while another container base without containers is lowered down through the right-side passage to the right-side low platform; in the second step, locomotive stops and containers with heavy masses are moved from container base on the left-side passage by robot arm and moved by a separate mini-locomotive to the final destination at the top platform while containers with heavy masses are put onto container base at the bottom of the right-side passage; in the third step, locomotive moves in opposite direction and lifts up the containers with heavy masses sitting on their bases through the right-side vertical passage while the base without containers are lowered down at the left-side vertical passage; in the fourth step, locomotive stops when the right-side container base with containers reaches the top of the passage; containers with heavy masses are moved by robot arms and moved by a separate mini-locomotive to the final destination at the top platform. In the meantime, the containers are put onto the container base at the bottom of the left-side passage; iteration from step one to step four repeats.

3. A method for lowering down containers with heavy masses and with electric machine in the locomotive working in generating mode for the system as claimed in claim 1, which consists of the steps as follows: in the first step, containers with heavy masses are put onto the container base sitting at the top of the left-side passage and then are lowered down through the left-side passage while the container base without containers at the right side is lifted up through belt towards the top of the right-side passage; in the second step, containers with heavy masses reaches the bottom of the left-side passage where containers are moved from the base and moved by a separate mini-locomotive to their destination at low platform; in the meantime, containers with heavy masses are put onto container base at the top of the right-side passage by robot arm; in the third step, electric locomotive moves in opposite direction; the containers with heavy masses on the right-side passage are lowered down towards its bottom or low platform on the right side; in the meantime, the container base without containers in the left-side passage is lifted up; in the fourth step, when the containers with heavy masses at the right-side passage reaches its bottom and are moved by robot arms and then further moved by a separate mini-locomotive to the final destination at the low platform; in the meantime the containers are put onto the container base reaching the top of left-side passage; iteration from step 1 to step 4 repeats.