A gravity energy storage system based on chain track type rigid engagement transmission and a collaborative control method thereof

Abstract

A gravity energy storage system based on chain track rigid engagement transmission and its collaborative control method belong to the technical field of gravity energy storage. The system contains at least one basic energy storage unit, which includes an inclined track, a carriage with a rigid drive baffle, a chain and plate system, a motor generator, an electric elevator, a continuously variable transmission and a sensor group. The surface of the chain and plate is provided with a convex sprocket gravity baffle, which forms a non-slip rigid engagement with the carriage baffle. The controller performs three-layer collaborative control: the carriage step scheduling is based on the rigid dynamics model; the speed ratio of the transmission is dynamically adjusted by combining the load change rate differential compensation to suppress the single-carriage power fluctuation; and the seamless relay of multiple units is realized through the power balance matrix. The invention makes the single-carriage power fluctuation less than 2%, the total system power fluctuation less than 2%, the AGC response not more than 300ms, the comprehensive efficiency reaches 87%-92%, and is suitable for large-scale energy storage construction in mountainous areas and abandoned mines.

Description

Technical Field

[0001] This invention belongs to the field of gravity energy storage technology, specifically relating to a system for energy storage and power generation utilizing mountainous, sloping, or abandoned mine terrain. In particular, it relates to a gravity energy storage system and its control method that achieves high efficiency, high stability, and fast response characteristics through the deep integration of a track-type rigid meshing transmission mechanism and a three-layer collaborative control method. Background Technology

[0002] To address the volatility of new energy power generation, such as wind and solar power, and the pressure on power grid peak shaving, gravity energy storage technology, as a large-capacity, long-life, and environmentally friendly energy storage method, is receiving widespread attention. Currently, mainstream energy storage methods include pumped hydro storage, compressed air storage, and electrochemical energy storage, but each has significant drawbacks: pumped hydro storage is highly dependent on terrain, has a long investment cycle, requires substantial construction work, and has a certain impact on the ecological environment; compressed air storage has low efficiency, requires large-scale gas storage devices and specific geological conditions, and even relies on burning fossil fuels for supplemental heating; electrochemical energy storage suffers from high costs, limited lifespan, and potential safety hazards.

[0003] In the field of gravity energy storage, existing inclined track solutions, such as Chinese patents CN119921481A and CN223923193U, mainly use push rods, winches, or flexible rigging to drive a carriage loaded with heavy objects downhill (generating electricity) or uphill (storing energy). However, the inventors have discovered in their research and practice that the above-mentioned existing solutions have the following fundamental technical defects:

[0004] 1. The contradiction between transmission efficiency and response speed: Intermittent transmission mechanisms such as flexible steel cables, chains, or push rods used in Chinese patent CN119921481A inevitably suffer from elastic deformation, slippage, or meshing gaps. This results in mechanical transmission efficiency typically below 85%, and a significant time lag (usually greater than 200ms) between changes in the force on the carriage and changes in the generator output power. This prevents the instructions of the upper-level scheduling algorithm from being executed accurately and quickly, severely affecting the system's responsiveness.

[0005] 2. Inherent instability in power output: During the descent of the carriage, its speed is easily affected by nonlinear factors such as friction, wind, and uneven track, which causes the power output of a single generator to fluctuate drastically (the fluctuation range is usually as high as 10%-15%), which deteriorates the grid-connected power quality and requires the addition of expensive energy storage and smoothing devices.

[0006] 3. Disconnect between scheduling algorithm and physical mechanism: Although existing technologies (such as CN119070492A) propose a macro-level scheduling strategy of "multi-vehicle staggered descent", their control models do not consider the power fluctuation characteristics of individual carriages or the time delay and efficiency loss caused by flexible transmission links. Therefore, this strategy has limited smoothing effect on total output power and cannot respond quickly and accurately to the automatic generation control (AGC) commands of the power grid. Summary of the Invention

[0007] The present invention aims to provide a gravity energy storage system based on a track-type rigid meshing transmission and its cooperative control method, so as to solve the technical problems of low transmission efficiency, slow response, drastic fluctuations in the output power of a single carriage and the total output power of the system, and the disconnect between the scheduling algorithm and the physical mechanism in the existing inclined track-type gravity energy storage technology.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0009] A gravity energy storage system based on a track-type rigid meshing transmission includes at least one basic energy storage unit. The basic energy storage unit includes:

[0010] The mechanical transmission chain includes an inclined track laid on a slope and a gravity carriage that can move along the track. The gravity carriage specifically includes a carriage body, wheels mounted on the bottom of the carriage body for rolling on the inclined track, and a rigid drive baffle fixed to the bottom of the carriage body. High-density materials (such as concrete blocks, ores, etc.) can be placed inside the carriage body as needed, and its total mass can be adjusted from 30 tons to 200 tons according to power requirements.

[0011] The power conversion chain includes a closed chain plate system, a raised sprocket gravity baffle fixed to the surface of the chain plate, and a gear set connected to the chain system. The raised sprocket gravity baffle matches the shape of the rigid drive baffle at the bottom of the carriage to achieve rigid engagement with no relative slippage and low time delay.

[0012] The power control chain includes a continuously variable transmission (CVT), an electric generator, and an electric hoist. The CVT can be selectively connected between the chain and plate system and the electric generator. In power generation mode, the chain and plate system drives the electric generator to rotate and generate electricity via the CVT; in energy storage mode, the electric hoist acts as a power source, driving the chain and plate system through another transmission path, thereby lifting the gravity-carrying car from the bottom of the slope to the top.

[0013] The sensing and execution module includes a high-resolution sensor array and a speed ratio actuator. The sensor array is used to collect dynamic data such as torque and speed of the continuously variable transmission (CVT) input / output shafts in real time, with a sampling rate of no less than 100Hz. The speed ratio actuator drives the CVT, with a speed ratio response time of less than 50ms.

[0014] The collaborative control system includes a central controller, which is connected to the power grid dispatch center, electric generators, electric hoists, continuously variable transmissions, and carriage position sensors.

[0015] The core collaborative logic lies in the rigid engagement of the "protruding sprocket gravity baffle" and the "rigid drive baffle," which forms a high-stiffness, low-delay, and highly deterministic force transmission interface. Based on this physical foundation, the collaborative control system executes a "three-level hierarchical collaborative control method," deeply integrating mechanical characteristics with control algorithms.

[0016] The three-layer hierarchical cooperative control method is as follows:

[0017] Layer 1: Mode switching and tiered grouping scheduling based on operating state machine

[0018] The main controller determines whether the system is in "power generation mode," "energy storage mode," or "standby mode" based on grid dispatch instructions. In power generation mode, the controller performs tiered grouping scheduling of multiple carriages based on a precise dynamic model of rigid meshing transmission. This model can be represented as:

[0019]

[0020] in, Let i be the power generation capacity of the i-th carriage. The rigid meshing efficiency coefficient is approximately constant 1 in this system due to the absence of relative slippage, which provides determinism for precise scheduling. The controller calculates the theoretical starting interval Δt based on this model, bringing the total power close to the target value and pre-compensating for known transmission losses.

[0021] Second layer: Real-time stepless speed regulation and frequency stabilization control of single carriage power

[0022] This layer addresses the challenge of "micro-fluctuations in power within a single carriage," a problem that existing technologies cannot solve. During the carriage's descent, the following closed-loop control is executed in real time:

[0023] 1. High-frequency sampling: Real-time acquisition of gearbox input shaft torque at a frequency of not less than 50Hz. Input speed and current speed ratio .

[0024] 2. Optimal speed ratio calculation with differential compensation: The controller calculates the optimal speed of the electric generator based on the target optimal speed. By combining the load change rate, the optimal speed ratio can be solved. The algorithm introduces a system inertia compensation term:

[0025]

[0026] Among them, It is a differential compensation function used to predict rapid changes in load (such as the impact at the moment of a new round of meshing between the carriage baffle and the sprocket baffle), and adjust the speed ratio in advance to eliminate power spikes in the microsecond to millisecond range from the source.

[0027] 3. Rapid execution: The controller drives the gearbox actuator to adjust the speed ratio within <50ms. To keep the generator speed constant at Within ±1%, the output power fluctuation of a single carriage is suppressed to <2%.

[0028] Third layer: Matrix power balancing and seamless relay control between multiple units

[0029] For M independent energy storage units operating in parallel, the controller constructs the following power balance matrix:

[0030]

[0031] in The mode factor for unit j (1 represents power generation, 0 represents energy storage). Controller constraints:

[0032] At any given time, at least one unit is in power generation mode, and the system's net power output is... Strictly track power grid dispatch instructions.

[0033] When one unit completes its power generation cycle and is about to switch to energy storage mode, the controller will instruct another unit that is in standby or low-speed uplink mode to immediately switch to power generation mode within 500ms, achieving "seamless relay" and completely avoiding power interruption or downtime.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. Superior power quality: Through the second-level control, the output frequency fluctuation of a single carriage can be controlled within ±0.1Hz; in conjunction with the first and third-level control, the total output power fluctuation of the system is less than 2%, which can directly meet the grid connection requirements without the need for additional energy storage smoothing devices.

[0036] 2. Ultra-fast response capability: Thanks to the synergy of low time delay (eliminating transmission backlash) and fast speed ratio adjustment (<50ms) of the rigid meshing structure, the system's response time to grid AGC commands can be shortened to less than 300ms, which is better than pumped storage (second level) and traditional gravity storage.

[0037] 3. High efficiency under all working conditions: The rigid transmission combined with adaptive speed ratio adjustment enables the system to maintain a stable single-pass electromechanical conversion efficiency of 87%-92% within a wide load range of 20%-100%, and the annual comprehensive charge-discharge efficiency can reach 80%-85%, which is better than pumped storage (about 75%-80%) and existing slope gravity energy storage (<70%).

[0038] 4. Low construction and operation costs: The construction cost of a single module is approximately 650-800 yuan / kW, lower than pumped storage and electrochemical energy storage. It also features minimal mechanical wear and long maintenance cycles.

[0039] 5. Easy to scale up: Each basic unit has independent "mechanical-electrical-control" capabilities, with stable output power, and can be linearly stacked like "LEGO modules" to the megawatt level; it can be combined with abandoned mines and mountain revegetation projects, with high space utilization. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the overall system structure;

[0041] Figure 2 This is a partially enlarged cross-sectional view of a rigid meshing transmission.

[0042] Figure 3 This is a diagram of the bottom structure of the gravity carriage;

[0043] Figure 4 This is the overall control logic block diagram of the system;

[0044] Figure 5 This is a diagram showing the operation of two sets of energy storage units connected in series.

[0045] Figure 6 Flowchart of stepless speed regulation and frequency stabilization control for a single carriage;

[0046] Figure 7 This is a timing diagram showing the phased start-up of multiple carriages and the smooth overlay of power.

[0047] Figure 8 Timing diagram for seamless handover switching between multiple units;

[0048] Figure 9 The output power of Scheme A and Scheme B is compared over time.

[0049] Figure 10 A bar chart or spectrum diagram comparing the generator frequency fluctuations of Scheme A and Scheme B;

[0050] In the diagram, 1-inclined track, 2-gravity car, 3-rigid drive baffle, 4-chain and chain plate system, 5-chain, 6-chain plate, 7-protruding sprocket gravity baffle, 8-electric generator, 9-electric hoist, 10-continuously variable transmission, 11-electric grid, 12-electric grid cable, 13-main control cabinet, 14-low voltage cable, 15-generator cable. Detailed Implementation

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0052] Example 1

[0053] like Figure 1 As shown, this embodiment provides a gravity energy storage system based on a tracked rigid meshing transmission, which is constructed on the slope of an abandoned mine. The system comprises multiple basic energy storage units operating in parallel; this embodiment uses one of these units as an example for illustration.

[0054] The basic energy storage unit includes:

[0055] Inclined track 1 is laid on a slope, and the slope can be selected according to the terrain, such as 25°-35°.

[0056] The gravity carriage 2 can move along the inclined track 1. The gravity carriage 2 includes a carriage body, gravity wheels, and multiple rigid drive baffles 3 fixed to the bottom of the carriage body. The surface of the baffles may be provided with a wear-resistant ceramic coating or rubber buffer pads. The total weight of the carriage can be configured according to requirements, for example, between 30 tons and 200 tons; this embodiment uses 70 tons.

[0057] The chain and chain plate system 4 includes a closed chain 5 and chain plates 6 fixed to the chain at equal intervals. Each chain plate has a raised sprocket gravity baffle 7 fixed to its surface. The upper surface of this baffle has a guide angle of 15°-30°, and the back has reinforcing ribs to ensure a non-slip, rigid engagement with the rigid drive baffle 3 of the carriage. The hinge spacing of the chain 5 (e.g., 500-1000mm) is strictly matched to an integer multiple of the spacing of the rigid drive baffle 3.

[0058] The power conversion module includes a gear set connected to the chain system, an electro-hydraulic servo-driven continuously variable transmission (CVT) 10, and a permanent magnet synchronous electric generator 8. The CVT's speed ratio response time is less than 50ms. Additionally, an electric hoist 9 is provided, which is connected to the chain system via another set of gears.

[0059] The sensing and execution module includes high-resolution torque and speed sensors (sampling rate ≥100Hz, 200Hz in this embodiment) installed on the input / output shaft of the transmission, and the actuator that drives the CVT.

[0060] The collaborative controller adopts a PLC + industrial computer architecture and communicates with the power grid dispatch center, electric generators, electric hoists, CVTs, and all sensors.

[0061] The system works as follows:

[0062] Energy storage process (upward): When there is a surplus of power from the grid, the controller commands the system to enter energy storage mode. The controller starts the electric hoist 9, which drives the chain and plate system 4 to reverse through the gear set connected to it. The raised sprocket gravity baffle 7 on the chain 5, through rigid engagement with the rigid drive baffle 3 of the carriage, pushes the gravity carriage 2 from the bottom of the slope along the inclined track 1 to the top of the slope, thereby converting electrical energy into gravitational potential energy for storage.

[0063] Power generation process (downward): When the power grid needs electricity, the controller commands the system to enter power generation mode. Under the influence of gravity, the gravity carriage 2 slides down from the top of the slope, and its rigid drive baffle 3 pushes the raised sprocket gravity baffle 7, driving the chain system to rotate forward. The rotation of the chain is transmitted to the electric generator 8 through the gear set and CVT, causing it to operate as a generator, converting gravitational potential energy into electrical energy and feeding it into the power grid. During this process, the electric hoist 9 is either disengaged or idling.

[0064] In summary, the electric generator is connected to the power grid and controller via cables, forming a loop for energy and information flow: the stator windings of the electric generator are directly connected to the power grid through an AC contactor or circuit breaker. In generation mode, it converts mechanical energy into electrical energy and feeds it into the power grid; in energy storage mode, it draws power from the grid to power the vehicle as an electric motor. Built-in or external sensors (such as encoders and temperature sensors) of the electric generator transmit real-time status signals such as speed, torque, and temperature to the controller (PLC / industrial computer) via signal cables. Based on these signals and power grid commands, the controller issues speed ratio adjustment commands to the actuators of the continuously variable transmission (CVT), forming a closed-loop control.

[0065] Example 2

[0066] Based on the aforementioned system hardware, the controller executes the following three-layer collaborative control method to achieve high-quality power output. Taking an 8MW constant power discharge command issued by the power grid as an example, the system has 20 units, with each generator having a rated power of 500kW.

[0067] 1. First-level control: tiered grouping and scheduling

[0068] The controller calculates that 16 units (16 × 500kW = 8MW) need to run simultaneously to meet the command. To avoid power surge caused by the simultaneous start-up of 16 carriages, the controller divides these 16 carriages into 4 groups based on the aforementioned rigid dynamics model, with each group starting at a 30-second interval, forming a macroscopically stable power plateau.

[0069] 2. Second-level control: Single-car power frequency stabilization

[0070] During the descent of any selected carriage (such as carriage number 1), the controller monitors the torque of its corresponding CVT input shaft in real time at a frequency of 200Hz. and rotational speed .

[0071] The sensor detects a rapid change in torque the instant the carriage baffle engages with a new sprocket baffle (e.g., At this point, the controller performs the optimal speed ratio calculation with differential compensation:

[0072]

[0073] in, The optimal operating speed of the generator (e.g., 1500 rpm). In this embodiment, the differential compensation function... It is preferably set as a linear function to pre-calculate a speed ratio correction amount (e.g., a reduction of 0.2) based on the magnitude of the load change rate.

[0074] Specifically, the differential compensation function The specific mathematical form and its engineering calibration method are as follows, to ensure that those skilled in the art can reproduce the compensation function under different working conditions without creative effort:

[0075] 1. Linear function form:

[0076]

[0077] in, Let be the dimensionless differential compensation coefficient. The physical meaning of this formula is: when When the load increases, corresponding to the instant the baffle engages, the value is >0 (when the load increases, corresponding to the instant the baffle engages). >1, making the optimal speed ratio The calculation result increases accordingly, and the controller drives the CVT actuator to increase the speed ratio in advance to overcome the impending drop in generator speed; When <0 (load decreases), If the speed ratio is less than 1, the speed ratio will be reduced accordingly to prevent speed overshoot.

[0078] 2. Compensation coefficient Engineering calibration method

[0079] The value of is related to the equivalent rotational inertia of the transmission chain. System damping ratio ξ and sensor sampling period Related. In this embodiment, the calibration steps are as follows:

[0080] The first step involves applying a step excitation of 10% of the rated torque to the chain and chain plate system via an electric hoist while the carriage is stationary. The speed response curve of the transmission chain is then obtained, and the equivalent inertial time constant is identified through system identification. (In this embodiment) (≈120ms)

[0081] The second step is to select the initial compensation coefficient based on the theory of optimal damping ratio for second-order systems. Where ξ is taken as 0.707, The sensor sampling period (in this embodiment) =5ms), calculated as follows ≈0.020;

[0082] The third step involves conducting a stepped load test (with the load increasing progressively at 10%, 20%, ..., 100% of the rated value), using the constraint that the maximum overshoot of the generator speed does not exceed ±1%. Fine-tuning was performed. In this embodiment, with a 70-ton carriage and a 25° gradient configuration, after calibration... The optimal value is 0.018. When the total weight of the carriage changes, only proportional adjustments are needed. Then repeat step three above to obtain the corresponding result. value.

[0083] In addition, regarding the gravity energy storage system in this patent (including the linear motion of the carriage, the rotational motion of the chain, chain plates, and gear sets), the following is determined: The process is as follows:

[0084] For the gravity energy storage system in this patent, determine The specific process is as follows:

[0085] First, the rotor shaft of the electric generator 8 is selected as the reference shaft for calculation, and its angular velocity is set to be... .

[0086] Then, according to the principle of conservation of kinetic energy, the kinetic energy of all moving parts is converted to the reference axis, and the total equivalent moment of inertia is... Calculate using the following formula:

[0087]

[0088] Where p is the total number of all rotating parts (including the chain and chain plate system, gear shafts of the gearbox, motor rotor, etc.). and Let be the inherent moment of inertia and actual rotational speed of the i-th rotating component, respectively; and q be the total number of all linear motion components (including the equivalent linear motion mass of the gravity carriage and chain plates). and Let be the mass and velocity of the j-th linear motion component, respectively.

[0089] In particular, for chain and sprocket systems, which simultaneously involve rotational motion (around the sprockets) and approximately linear motion (the portion located on the track), their mass can be decomposed according to the form of motion and attributed to the rotational terms. and linear terms The transmission ratio between any moving link in the transmission chain and the motor shaft is determined based on the rotational speed of that link and... The ratio is determined. Summing the above terms yields the total equivalent moment of inertia of the system. .

[0090] Within 30ms, the controller instructs the CVT actuator to adjust the speed ratio to... This allows the load torque at the generator end to be instantly compensated, and the generator speed to remain stable within the range of 1500±5 rpm, thereby suppressing the output power fluctuation of a single carriage to within 1.5% and eliminating power spikes and oscillations caused by mechanical meshing.

[0091] Compared with the prior art (Solution A): Publication No. CN119070492A which does not adopt this control strategy, the output power curve (lower curve) of the present invention (Solution B) is extremely flat.

[0092] 3. Third-level control: Matrix power balancing and seamless relay

[0093] As car number 1 approaches the bottom of the slope and its power generation begins to naturally decrease, the position sensor sends a signal to the controller. The controller then uses the power balance matrix to...

[0094]

[0095] It was detected that if no measures are taken, the total power will fall below the commanded value of 8MW.

[0096] The controller makes a rapid decision within 200ms: instructs another carriage, number 21, which has already completed its upward movement and is in standby mode, to immediately begin generating power downwards (by adjusting its mode factor). (Set as 1). Due to the rapid response and deterministic rigid transmission of the CVT, the power generation of carriage 21 can reach the rated value in a very short time (<200ms), accurately compensating for the power gap caused by the withdrawal of carriage 1. Seamless power transfer is achieved, ensuring that the power output to the grid remains stable at 8MW±0.1MW, with fluctuations of less than 1.25%.

[0097] Example 3

[0098] Performance comparison and effect verification:

[0099] In order to quantify and verify the technical effect of the present invention, the applicant conducted a simulation comparison based on the same physical parameters (track 200m, gradient 25°, carriage 80t, generator rated 1500rpm).

[0100] Comparison Scheme A (existing technology CN119070492A): adopts flexible steel cable + winch transmission, relies only on macro-level scheduling of multiple cars, and does not perform real-time speed ratio adjustment of individual cars.

[0101] Comparison Scheme B (the present invention): The present invention adopts a track-type rigid meshing transmission and executes a three-layer cooperative control method including a second-layer control (100Hz sampling + differential compensation speed ratio adaptive).

[0102] Simulation results are attached. Figure 9 and Figure 10 As shown:

[0103] Power fluctuation: The peak-to-peak output power fluctuation of Scheme A is as high as 15.6%. The output power fluctuation of Scheme B is controlled within 1.8%, and less than 1% in steady state.

[0104] Frequency fluctuations: The generator frequency of Scheme A has a maximum positive deviation of +2.3Hz and a maximum negative deviation of -2.3Hz, which seriously exceeds the grid connection standard (±0.2Hz). The frequency of Scheme B has a maximum positive deviation of +0.3Hz and a maximum negative deviation of -0.3Hz, which is close to the grid connection standard and fully meets the standard after coordinating with multi-vehicle dispatching.

[0105] Response time: Simulating a 10% instantaneous load disturbance, Scheme A has a settling time of approximately 1.2 seconds and a maximum frequency deviation of ±1.8 Hz. Scheme B can recover to stability within 0.15 seconds, with a frequency deviation of less than ±0.2 Hz.

[0106] To demonstrate the universality of the control strategy of this invention under different operating conditions, the applicant conducted field tests under three typical operating conditions, using the same hardware configuration (200m track, 25° gradient, generator rated speed 1500rpm). The test results are as follows:

[0107] Operating condition number Carriage quality After calibration value Power fluctuation (peak-to-peak value) Maximum frequency offset AGC response time 1 50 tons 0.022 1.6% ±0.2Hz 280ms 2 80 tons 0.018 1.7% ±0.3Hz 290ms 3 120 tons 0.015 1.9% ±0.3Hz 295ms

[0108] The above verification examples demonstrate that, under different car body mass conditions, only recalibration according to the method described in this paper is required. and After adopting the differential compensation function of the present invention, the power fluctuation of a single carriage is stably suppressed to within 2%, the frequency deviation is less than ±0.3Hz, and the AGC response time is no more than 300ms. This proves that the technical solution of the present invention has significant stability and repeatability. Those skilled in the art can fully implement the present invention under different working conditions according to the instructions in the specification.

[0109] In summary, this invention, through the deep synergy of mechanical structure and control algorithm, successfully solves the core pain points of existing gravity energy storage technology, and has extremely high industrial practical value and broad prospects for promotion and application.

[0110] It should be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0111] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A gravity energy storage system based on a track-type rigid meshing transmission, characterized in that, It includes at least one basic energy storage unit, the basic energy storage unit comprising: Inclined track (1); Gravity car (2), which is movably disposed on the inclined track (1), the gravity car (2) includes a car body, wheels installed at the bottom of the car body for rolling on the inclined track, and a rigid drive baffle (3) fixed to the bottom of the car body. The chain and plate system (4) includes a closed chain (5) and a plate (6), the surface of which is provided with a raised sprocket gravity baffle (7), which is matched with the rigid drive baffle (3) to achieve a non-slip rigid engagement; Electric generator (8); An electric hoist (9) is connected to the chain and plate system (4) for driving the gravity carriage (2) upward along the inclined track (1) in energy storage mode. A continuously variable transmission (10) is connected on the transmission path between the chain and plate system (4) and the electric generator (8) for adjusting the speed of the electric generator (8) in power generation mode; A sensor array is used to collect the input torque and input speed of the continuously variable transmission (10) in real time; The controller is communicatively connected to the electric generator (8), electric hoist (9), continuously variable transmission (10), and sensor group, and is configured to perform the following coordinated control steps: a) Determine the overall system operation mode and schedule the tiered operation of multiple carriages according to the power grid dispatch instructions; b) During the downward power generation process of a single carriage, the speed ratio of the continuously variable transmission is dynamically adjusted based on the real-time data collected by the sensor group and combined with the differential compensation of the load change rate, so that the speed of the electric generator is kept constant at the preset optimal value, thereby suppressing the instantaneous power fluctuation caused by the mechanical meshing process. c) When multiple units are running in parallel, the operating mode of each unit is forcibly allocated according to the power balance matrix to achieve seamless power relay.

2. The system according to claim 1, characterized in that, The upper surface of the raised sprocket gravity baffle (7) is provided with a guide angle of 15° to 30°, and its back is provided with reinforcing ribs.

3. The system according to claim 1, characterized in that, The sampling rate of the sensor group is not less than 100Hz.

4. The system according to claim 1, characterized in that, The hinge spacing between adjacent chain plates (6) in the chain plate system (4) is strictly matched to the spacing of the rigid drive baffle (3) of the carriage.

5. The system according to claim 1, characterized in that, The continuously variable transmission (10) is driven by an electro-hydraulic servo or a servo motor, and its speed ratio response time is less than 50ms.

6. The system according to claim 1, characterized in that, The surface of the rigid drive baffle (3) is provided with a wear-resistant ceramic coating or a rubber buffer layer.

7. A cooperative control method applied to the system according to any one of claims 1-6, characterized in that, Includes the following steps: Step S1: According to the grid dispatch instructions, the system switches between power generation mode, energy storage mode or standby mode, and performs tiered grouping and dispatching of multiple carriages in power generation mode. Step S2: Single-car stepless speed regulation and frequency stabilization control, which specifically includes: S21: Real-time acquisition of transmission input torque at a frequency of not less than 50Hz and input speed ; S22: Based on the preset optimal generator speed and current And combined with the load change rate The differential compensation function is used to solve for the optimal speed ratio. ; S23: The drive transmission will adjust the gear ratio to [the specified value] within 50ms. To stabilize the generator speed at Within ±1% range; Step S3: Multi-unit matrix power balance control, according to the formula Coordinate all units, force at least one unit to be in power generation mode, and achieve seamless handover when switching units.

8. The method according to claim 7, characterized in that, The differential compensation function is a linear function used to predict load changes caused by the meshing impact of the baffles.

9. The method according to claim 7, characterized in that, After step S2 control, the output power fluctuation of a single carriage is suppressed to less than 2%.

10. The method according to claim 7, characterized in that, After three-layer coordinated control, the total output power fluctuation of the system is less than 2%, and the response time to the automatic power generation control command of the power grid is no more than 300ms.

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