Operation control method and system of gravity energy storage system

Abstract

The invention discloses an operation control method and system for a gravity energy storage system, and aims to solve the problems of long-time-scale power fluctuation of more than 10s and short-time-scale power fluctuation of less than 10s caused by switching of a unit and a weight in gravity energy storage. According to the multi-unit and multi-weight time sequence cooperation and the operation control method of the coupling power type energy storage system, the problem of power fluctuation caused by frequent start and stop of multiple weights in the multi-unit and multi-weight switching process of a gravity energy storage system is effectively solved. According to the method, by means of time sequence cooperation of the working lift cars and the empty lift cars in the units and between the units, the number of gravity energy storage shafts and lift cars can be effectively reduced, the overall construction cost is reduced, improvement and optimization can be conveniently carried out in newly-built and existing gravity energy storage systems, and the application range is wide.

Description

Technical Field

[0001] The present invention belongs to the technical field of gravity energy storage, and in particular relates to an operation control method and system of a gravity energy storage system. Background Art

[0002] At present, renewable energy is developing rapidly. A high proportion of renewable energy generation is gradually replacing traditional thermal power generation. The energy source structure of the power system is gradually optimized, and finally a green and sustainable green power system is realized. However, the large-scale grid connection of renewable energy such as wind power and photovoltaic power will also bring problems such as randomness and instability. Therefore, ensuring the stability of the power grid under the premise of vigorously developing new energy power systems is an urgent problem to be solved in the field of power energy. The emergence of gravity energy storage technology is expected to solve the problems of imbalance, instability, and randomness faced by the current power system.

[0003] In the existing gravity energy storage system solutions, due to the limitations of the weight and speed of the hoist, it is difficult to increase the power of a single unit, and small and medium-capacity energy storage modules are often used to form an array to achieve the supply of large-scale, large-capacity gravity energy storage system resources. However, the power fluctuation problem faced by the unit energy storage module during the heavy object replacement process will also cause certain harm to the stable operation of the system; therefore, it is necessary to add a power smoothing solution for the energy storage motor to the gravity energy storage system to ensure the stable operation of the system.

[0004] The existing multi-machine system power smoothing generally uses a single machine internal multiple block power smoothing solution. If the total number of cars is M, the number of working cars is usually only half. While the working car weight blocks are unloaded, the same number of spare cars must be loaded with weight blocks to avoid power interruptions. The problem with this technical solution is that the number of wells and cars is doubled, resulting in an increase in the cost of the energy storage system. Therefore, in the gravity energy storage system, there is an urgent need for a multi-unit power smoothing method that can achieve a smooth and continuous input and output of electrical energy with as little or no additional equipment as possible and ensure the overall cost of the system. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention proposes an operation control method and system for a gravity energy storage system.

[0006] The technical solution of the present invention is as follows:

[0007] A method for controlling the operation of a gravity energy storage system, wherein a plurality of groups of gravity energy storage units in the gravity energy storage system are connected to a power grid using a multi-synchronous machine grid-connected mode, the method comprising:

[0008] Determine the gravity energy storage units that need to be started and loaded to meet the power demand of the power grid;

[0009] The determined gravity energy storage units are started in sequence with multiple synchronous units, and the load increase and decrease sequence coordination control of multiple blocks within a single unit and between multiple units is adopted.

[0010] Furthermore, the specific steps of determining the gravity energy storage unit that needs to be started and loaded to meet the power demand of the power grid include:

[0011] The number of gravity energy storage units that need to be started and loaded to meet the power demand of the power grid is determined according to the judgment formula, thereby completing the determination of the gravity energy storage units. The judgment formula is as follows:

[0012] P R ≤NP in

[0013] P R >(N-1)P in

[0014] Where P R P is the power demanded by the grid; in is the rated power of the synchronous machine operating in the high efficiency range; N is the number of synchronous units to determine the starting load.

[0015] Furthermore, the specific method for sequentially starting the multiple synchronous generator sets includes:

[0016] T n =T 1 +(n-1)t

[0017] Where, T n is the start-up time of the nth synchronous unit; T 1 is the start-up time of the first synchronous unit; t is the start-up time interval of multiple synchronous units in sequential start-up.

[0018] Furthermore, the specific method for controlling the timing coordination of load addition and reduction of multiple objects within the single unit includes:

[0019] For a single unit with M load cars, the specific method of energy storage control includes:

[0020] m working cars are driven by the working unit to carry heavy objects upward for energy storage operation. At the same time, Mm empty cars are driven by the auxiliary unit to fall for the next cycle. The ratio of the number of working cars m to the number of empty cars Mm is determined according to the operating speed of the working unit and the operating speed of the auxiliary unit, m / (Mm) <V a / V m ; The charging power of a single unit is basically constant, which is the sum of the powers of m working cars;

[0021] The specific methods for controlling the energy-releasing power generation work include:

[0022] m working cars carry heavy objects downward to release energy and generate electricity. At the same time, Mm cars are driven by the auxiliary unit to move up for the next cycle. The ratio of the number of working cars m to the number of standby cars Mm is determined by the operating speed of the working unit and the operating speed of the auxiliary unit, m / (Mm) <V a / V m ; The power generation power of a single unit is basically constant, which is the sum of the powers of m working cars; the utilization rate of the hoistway car and the drive shaft is m / M*100%.

[0023] Furthermore, the ratio of the number of the working cars to the number of the empty cars is 5:1, 3:1 or 2:1.

[0024] Furthermore, the specific method for controlling the timing coordination of load addition and reduction of multiple objects among the multiple units includes:

[0025] Several groups of gravity energy storage units in the gravity energy storage system are divided into grid-connected groups, each of which is provided with two gravity energy storage units; in the energy storage work control or energy release and power generation work control, the grid-connected groups are operated at intervals and the working car of one gravity energy storage unit of each grid-connected group is cut in, and the working car of the other gravity energy storage unit is cut out.

[0026] Furthermore, the gravity energy storage system is a gravity energy storage system coupled with a flywheel or a supercapacitor.

[0027] An operation control system of a gravity energy storage system, wherein a plurality of groups of gravity energy storage units in the gravity energy storage system are connected to a power grid using a multi-synchronous machine grid-connected mode, and the system comprises: a startup loading determination module and a timing control module;

[0028] The startup loading determination module is used to determine the gravity energy storage units that need to be started and loaded to meet the power demand of the power grid;

[0029] The timing control module is used to start multiple synchronous units in a timing sequence for the determined gravity energy storage units, and adopts the timing coordination control of multiple blocks of load addition and reduction within a single unit and between multiple units.

[0030] Furthermore, the specific steps of determining the gravity energy storage unit that needs to be started and loaded to meet the power demand of the power grid include:

[0031] The number of gravity energy storage units that need to be started and loaded to meet the power demand of the power grid is determined according to the judgment formula, thereby completing the determination of the gravity energy storage units. The judgment formula is as follows:

[0032] P R ≤NP in

[0033] P R >(N-1)Pin

[0034] Where P R P is the power demanded by the grid; in is the rated power of the synchronous machine operating in the high efficiency range; N is the number of synchronous units to determine the starting load.

[0035] Furthermore, the specific method for sequentially starting the multiple synchronous generator sets includes:

[0036] T n =T 1 +(n-1)t

[0037] Where, T n is the start-up time of the nth synchronous unit; T 1 is the start-up time of the first synchronous unit; t is the start-up time interval of multiple synchronous units in sequential start-up.

[0038] Furthermore, the specific method for controlling the timing coordination of load addition and reduction of multiple objects within the single unit includes:

[0039] For a single unit with M load cars, the specific method of energy storage control includes:

[0040] m working cars are driven by the working unit to carry heavy objects upward for energy storage operation. At the same time, Mm empty cars are driven by the auxiliary unit to fall for the next cycle. The ratio of the number of working cars m to the number of empty cars Mm is determined according to the operating speed of the working unit and the operating speed of the auxiliary unit, m / (Mm) <V a / V m ; The charging power of a single unit is basically constant, which is the sum of the powers of m working cars;

[0041] The specific methods for controlling the energy-releasing power generation work include:

[0042] m working cars carry heavy objects downward to release energy and generate electricity. At the same time, Mm cars are driven by the auxiliary unit to move up for the next cycle. The ratio of the number of working cars m to the number of standby cars Mm is determined by the operating speed of the working unit and the operating speed of the auxiliary unit, m / (Mm) <V a / V m ; The power generation power of a single unit is basically constant, which is the sum of the powers of m working cars; the utilization rate of the hoistway car and the drive shaft is m / M*100%.

[0043] Furthermore, the ratio of the number of the working cars to the number of the empty cars is 5:1, 3:1 or 2:1.

[0044] Furthermore, the specific method for controlling the timing coordination of load addition and reduction of multiple objects among the multiple units includes:

[0045] Several groups of gravity energy storage units in the gravity energy storage system are divided into grid-connected groups, each of which is provided with two gravity energy storage units; in the energy storage work control or energy release and power generation work control, the grid-connected groups are operated at intervals and the working car of one gravity energy storage unit of each grid-connected group is cut in, and the working car of the other gravity energy storage unit is cut out.

[0046] Furthermore, the gravity energy storage system is a gravity energy storage system coupled with a flywheel or a supercapacitor.

[0047] An electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor is used to call and run the computer program stored in the memory to execute any of the methods described above.

[0048] A computer-readable storage medium stores a computer program, wherein the computer program implements the steps of any of the above methods when executed by a processor.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] The present invention proposes an operation control method and system for a gravity energy storage system. The method aims to solve the power fluctuation problems of longer time scales of more than 10s and shorter time scales of less than 10s caused by switching of units and heavy objects in gravity energy storage. The method proposes a time-sequential coordination of multiple units and multiple objects, and an operation control method for a gravity energy storage system coupled with a flywheel or a supercapacitor, which effectively solves the power fluctuation problem caused by the frequent start and stop of multiple objects in the switching process of multiple units and multiple objects in the gravity energy storage system.

[0051] The method of the present invention utilizes the timing coordination of working cars and empty cars within and between units, which will effectively reduce the number of gravity energy storage shafts and cars and reduce the overall construction cost, facilitate improvement and optimization in new and existing gravity energy storage systems, and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 A schematic diagram of a gravity energy storage system in an embodiment;

[0053] Figure 2 Schematic diagram of a gravity energy storage multi-synchronous machine grid-connected system in an embodiment;

[0054] Figure 3 This is a flow chart of the operation control method of the gravity energy storage system in the embodiment;

[0055] Figure 4 The power fluctuation curve of the single gravity energy storage machine with multiple blocks loaded sequentially and simultaneously in the embodiment;

[0056] Figure 5 This is a diagram showing the power smoothing effect among multiple units of gravity energy storage in the embodiment;

[0057] Figure 6 This is a schematic diagram showing the change in the number of weight blocks of Unit 1# in each working cycle in the embodiment;

[0058] Figure 7 Schematic diagram of the operation control strategy of the gravity energy storage system in the embodiment. DETAILED DESCRIPTION

[0059] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent modifications of the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0060] Embodiment 1:

[0061] The present invention provides an operation control method of a gravity energy storage system, such as Figure 1 and Figure 2 As shown, several groups of gravity energy storage units in the gravity energy storage system are connected to the power grid using a multi-synchronous machine grid-connected mode, that is, each gravity energy storage unit is equipped with a synchronous machine, and the gravity energy storage devices in the gravity energy storage units are connected to the power grid after passing through their respective synchronous machines. Due to the multi-synchronous machine grid-connected mode of the gravity energy storage system, it is impossible to use an inverter to control the speed of the synchronous unit. Therefore, if multiple objects are loaded at the same time, it will cause a large power fluctuation, even exceeding 50%, causing an impact on the power grid. The operation control method of the present invention is used to smooth the grid-connected power of the gravity energy storage system. Figure 3 As shown, the method of the present invention comprises the following specific steps:

[0062] S1. Determine the gravity energy storage units that need to be started and loaded to meet the power demand of the power grid;

[0063] S2. Start the determined gravity energy storage units in multiple synchronous units in a timed manner, and adopt the coordinated control of multiple block load increase and decrease timing within a single unit and between multiple units.

[0064] Embodiment 2:

[0065] This example is further designed on the basis of the first embodiment in that the specific steps of determining the gravity energy storage unit that needs to be started and loaded to meet the power demand of the power grid in this example include:

[0066] According to the judgment formula, the number of gravity energy storage units that need to be started and loaded to meet the power demand of the power grid is determined, thereby completing the determination of the gravity energy storage units. The judgment formula is as follows:

[0067] P R≤NP in

[0068] P R >(N-1)P in

[0069] Where P R P is the power demanded by the grid; in is the rated power of the synchronous machine operating in the high efficiency range; N is the number of synchronous units to determine the starting load.

[0070] Embodiment three:

[0071] This example is further designed on the basis of the first embodiment in that the specific method for sequentially starting the multiple synchronous generators in this example includes:

[0072] T n =T 1 +(n-1)t

[0073] Where, T n is the start-up time of the nth synchronous unit; T 1 is the start-up time of the first synchronous unit; t is the start-up time interval of multiple synchronous units in sequential start-up.

[0074] Embodiment 4:

[0075] This example is further designed on the basis of the first embodiment in that the power switching between different weights in a single unit is smoothed, and the timing coordination method is adopted to utilize the coordination between the auxiliary unit for lifting the empty car and the working unit to control the number of weights on the drive shaft, thereby controlling the input and output power of the system. The operating speed of the working unit is V m , the operating speed of the auxiliary unit is V a ,

[0076] The time step of the heavy object switching of the working unit is Δt, which satisfies the following relationship:

[0077] Take a single unit driving 24 heavy-load elevators as an example:

[0078] A single unit has 24 weighted cars for lifting and lowering weights. The energy storage working state is: 12 working cars are used to carry weights upward for energy storage operation, while 12 empty cars are driven down by the auxiliary unit for the next cycle; the number of working cars is the same as the number of empty cars, and the operating speed of the auxiliary unit is V a Ratio of the working unit running speed V mSlightly faster; the input power of a single unit is basically constant, which is the power corresponding to the operation of 12 working cars. Similarly, the state of its energy release and power generation operation is: 12 cars are used to carry heavy objects downward for energy release and power generation operation, and at the same time, 12 empty cars are driven by the auxiliary unit to lift for the next cycle; the number of working cars is the same as the number of empty cars, and the operating speed of the auxiliary unit V a is the operating speed V of the working unit m Slightly faster; the power generation capacity of a single unit is basically constant, which is the sum of the power of the 12 working cars; the utilization rate of the hoistway car is relatively low, only 50%.

[0079] like Figure 4 As shown, the specific method for controlling the timing coordination of load addition and reduction of multiple objects within a single unit in this example includes:

[0080] For a single unit with M load cars, the specific method of energy storage control includes:

[0081] m working cars are driven by the working unit to carry heavy objects upward for energy storage operation. At the same time, Mm empty cars are driven by the auxiliary unit to fall for the next cycle. The ratio of the number of working cars m to the number of empty cars Mm is determined according to the operating speed of the working unit and the operating speed of the auxiliary unit, m / (Mm) <V a / V m ; The charging power of a single unit is basically constant, which is the sum of the powers of m working cars;

[0082] The specific methods for controlling the energy-releasing power generation work include:

[0083] m working cars carry heavy objects downward to release energy and generate electricity. At the same time, Mm cars are driven by the auxiliary unit to move up for the next cycle. The ratio of the number of working cars m to the number of standby cars Mm is determined according to the operating speed of the working unit and the operating speed of the auxiliary unit, m / Mm) <V a / V m The power generation of a single unit is basically constant, which is the sum of the power of m working cars. The utilization rate of the hoistway car and the drive shaft is m / M*100%. The faster the empty car runs, the higher the proportion of the working car, the greater the energy storage power that a single unit can achieve, and the higher the utilization rate of the hoistway car.

[0084] Embodiment five:

[0085] This example is further designed on the basis of the fourth embodiment in that the ratio of the number of working cars to the number of empty cars in this example is 5:1, 3:1 or 2:1. The following example specifically illustrates the working state of the car during energy storage and energy release. In this example, there are 16 working cars and 8 empty cars. The ratio of the number of working cars to the number of empty cars is 2:1. In order to improve the energy storage power of a single unit and the utilization rate of the shaft car and the drive shaft, it can be achieved by increasing the transportation speed of the empty cars. The state of the energy storage operation is: 16 working cars are used to carry heavy objects upward for energy storage operation. At the same time, the 8 empty cars are driven down by the auxiliary unit to perform the next cycle; the number of working cars is twice the number of empty cars, and the operating speed V of the auxiliary unit is 2. a is the operating speed V of the working unit m The charging power of a single unit is basically constant, which is the sum of the power of the 16 working cars. Similarly, the state of its energy-release power generation is: 16 working cars are used to carry heavy objects downward for energy-release power generation, while 8 empty cars are driven by the auxiliary unit to lift for the next cycle; the number of working cars is twice the number of empty cars, and the operating speed V of the auxiliary unit is a is the operating speed V of the working unit m The power generation capacity of a single unit is basically constant, which is the sum of the power of 16 working cars; the utilization rate of the hoistway car is 66.7%.

[0086] Embodiment six:

[0087] This example is further designed on the basis of the first embodiment in that, due to the limitation of the running speed of the empty car, the utilization rate of the hoistway car is low, resulting in a certain waste of resources. The specific method of the timing coordination control of multiple blocks adding and reducing loads between multiple units in this example includes:

[0088] Several groups of gravity energy storage units in the gravity energy storage system are divided into grid-connected groups, each of which is provided with two gravity energy storage units; in the energy storage work control or energy release and power generation work control, the grid-connected groups are operated at intervals and the working car of one gravity energy storage unit of each grid-connected group is cut in, and the working car of the other gravity energy storage unit is cut out.

[0089] In this example, the power fluctuation characteristics between the normally operating energy storage units are smoothed. Therefore, the peak power value and valley power value of the units are matched, and the matching method between units is adopted to make the total input and output power of the system stable. Figure 5 shown.

[0090] For the case of a single system with four units, the impact on the unit during the process of each heavy object being cut in and out is 10%. For the system composed of four units as a whole, when the heavy objects of each unit are cut in and out at the same time, the power fluctuation of the system is also 10%. The power smoothing strategy proposed in the present invention is adopted to divide the four units into two grid-connected groups. By adjusting and controlling each grid-connected group to cut in one unit and cut out the other unit at the same time, and adding corresponding coordination measures, it is ensured that the power fluctuation of each grid-connected group is not large, thereby ensuring the stable input and output of power of the system.

[0091] The 1# and 4# units form a grid-connected group.

[0092] The working cycle of unit 1# is #1+→#1→#1→#1-→#1→#1→#1+

[0093] The working rhythm of unit 4# is #4-→#4→#4→#4+→#4→#4→#4→#4-

[0094] The 2# and 3# units form a grid-connected group.

[0095] The working rhythm of unit 2# is #2+→#2→#2→#2-→#2→#2→#2+

[0096] The working rhythm of unit 3# is #3-→#3→#3→#3+→#3→#3→#3→#3-

[0097] Taking unit 1# as an example, the number of weight blocks changes in each working cycle as follows: Figure 6 As shown. Figure 6 It can be seen that if the time interval for a working car in Unit 1# to unload a load and then reload a new load is 3, Unit 1# only needs to add 2 spare cars to achieve continuous operation.

[0098] Embodiment seven:

[0099] This example is further designed on the basis of Example 1 in that the gravity energy storage system in this example is a gravity energy storage system coupled with a flywheel or a supercapacitor. Based on the above example, although the utilization rate of the gravity energy storage shaft and the car can be effectively improved and the economy of the overall system can be improved, the power fluctuation problem of a longer time scale (more than 10s) caused by the switching process of the unit and the heavy object can also be solved, but the power fluctuation problem of a shorter time scale (less than 10s, oscillation frequency>0.1Hz) caused by the electromagnetic torque of the motor and the mechanical load torque oscillation cannot be solved. In order to solve the short-term power fluctuation problem, it is also necessary to couple the flywheel or supercapacitor energy storage system for rapid power compensation; the energy storage system is electrically coupled to the synchronous machine system through the converter. Through the coordination of multiple objects in a single unit, the coordination of multiple objects between units, and the power smoothing method of the energy storage system coupled with a flywheel or a supercapacitor, the power fluctuation problem caused by the frequent start and stop of multiple objects in the switching process of multiple units and multiple objects in the gravity energy storage system will be effectively solved. Figure 7 shown.

[0100] Embodiment eight:

[0101] The present invention provides an operation control system for a gravity energy storage system, wherein a plurality of groups of gravity energy storage units in the gravity energy storage system are connected to the power grid in a multi-synchronous machine grid-connected mode, that is, each gravity energy storage unit is equipped with a synchronous machine, and the gravity energy storage devices in the gravity energy storage units are connected to the power grid after being connected to the synchronous machine, and the operation control method is used to smooth the grid-connected power of the gravity energy storage system, and the system comprises: a startup loading determination module and a timing control module;

[0102] A startup loading determination module is used to determine the gravity energy storage units that need to be started and loaded to meet the power demand of the power grid;

[0103] The timing control module is used to start multiple synchronous units of the determined gravity energy storage units in a timing manner, and adopts the timing coordination control of multiple blocks of load addition and reduction within a single unit and between multiple units.

[0104] Furthermore, the specific steps of determining the gravity energy storage unit that needs to be started and loaded to meet the power demand of the power grid include:

[0105] The number of gravity energy storage units that need to be started and loaded to meet the power demand of the power grid is determined according to the judgment formula, thereby completing the determination of the gravity energy storage units. The judgment formula is as follows:

[0106] P R ≤NP in

[0107] P R >(N-1)P in

[0108] Where PR P is the power demanded by the grid; in is the rated power of the synchronous machine operating in the high efficiency range; N is the number of synchronous units to determine the starting load.

[0109] Furthermore, the specific method for sequentially starting the multiple synchronous generator sets includes:

[0110] T n =T 1 +(n-1)t

[0111] Where, T n is the start-up time of the nth synchronous unit; T 1 is the start-up time of the first synchronous unit; t is the start-up time interval of multiple synchronous units in sequential start-up.

[0112] Furthermore, the specific method for controlling the timing coordination of load addition and reduction of multiple objects within the single unit includes:

[0113] For a single unit with M load cars, the specific method of energy storage control includes:

[0114] m working cars are driven by the working unit to carry heavy objects upward for energy storage operation. At the same time, Mm empty cars are driven by the auxiliary unit to fall for the next cycle. The ratio of the number of working cars m to the number of empty cars Mm is determined according to the operating speed of the working unit and the operating speed of the auxiliary unit, m / Mm) <V a / V m ; The charging power of a single unit is basically constant, which is the sum of the powers of m working cars;

[0115] The specific methods for controlling the energy-releasing power generation work include:

[0116] m working cars carry heavy objects downward to release energy and generate electricity. At the same time, Mm cars are driven by the auxiliary unit to move up for the next cycle. The ratio of the number of working cars m to the number of standby cars Mm is determined by the operating speed of the working unit and the operating speed of the auxiliary unit, m / (Mm) <V a / V m ; The power generation power of a single unit is basically constant, which is the sum of the powers of m working cars; the utilization rate of the hoistway car and the drive shaft is m / M*100%.

[0117] Furthermore, the ratio of the number of the working cars to the number of the empty cars is 5:1, 3:1 or 2:1.

[0118] Furthermore, the specific method for controlling the timing coordination of load addition and reduction of multiple objects among the multiple units includes:

[0119] Several groups of gravity energy storage units in the gravity energy storage system are divided into grid-connected groups, each of which is provided with two gravity energy storage units; in the energy storage work control or energy release and power generation work control, the grid-connected groups are operated at intervals and the working car of one gravity energy storage unit of each grid-connected group is cut in, and the working car of the other gravity energy storage unit is cut out.

[0120] Furthermore, the gravity energy storage system is a gravity energy storage system coupled with a flywheel or a supercapacitor.

[0121] Embodiment nine:

[0122] An electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor is used to call and run the computer program stored in the memory to execute any of the methods described above.

[0123] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of any of the above methods are implemented.

[0124] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention.

Claims

1. An operation control method for a gravity energy storage system, wherein a plurality of groups of gravity energy storage units in the gravity energy storage system are connected to a power grid using a multi-synchronous machine grid-connected mode, characterized in that: The method comprises: Determine the gravity energy storage units that need to be started and loaded to meet the power demand of the power grid; The determined gravity energy storage units are started in sequence with multiple synchronous units, and the load increase and decrease sequence coordination control of multiple blocks within a single unit and between multiple units is adopted.

2. The operation control method of the gravity energy storage system according to claim 1, characterized in that: The specific steps of determining the gravity energy storage unit that needs to be started and loaded to meet the power demand of the power grid include: The number of gravity energy storage units that need to be started and loaded to meet the power demand of the power grid is determined according to the judgment formula, thereby completing the determination of the gravity energy storage units. The judgment formula is as follows: P R ≤NP in P R >(N-1)P in Where P R P is the power demanded by the grid; in is the rated power of the synchronous machine operating in the high efficiency range; N is the number of synchronous units to determine the starting load.

3. The operation control method of the gravity energy storage system according to claim 1, characterized in that: The specific method for sequentially starting the multi-synchronous generator set includes: T n =T1+(n-1)t Where, T n is the start-up time of the nth synchronous unit; T1 is the start-up time of the first synchronous unit; t is the start-up time interval of multiple synchronous units in sequential start-up.

4. The operation control method of the gravity energy storage system according to claim 1, characterized in that: The specific method for controlling the timing coordination of load addition and reduction of multiple objects within the single unit includes: For a single unit with M load cars, the specific method of energy storage control includes: m working cars are driven by the working unit to carry heavy objects upward for energy storage operation. At the same time, Mm empty cars are driven by the auxiliary unit to fall for the next cycle. The ratio of the number of working cars m to the number of empty cars Mm is determined according to the operating speed of the working unit and the operating speed of the auxiliary unit, m / (Mm) <V a / V m ; The charging power of a single unit is basically constant, which is the sum of the powers of m working cars; The specific methods for controlling the energy-releasing power generation work include: m working cars carry heavy objects downward to release energy and generate electricity. At the same time, Mm cars are driven by the auxiliary unit to move up for the next cycle. The ratio of the number of working cars m to the number of standby cars Mm is determined by the operating speed of the working unit and the operating speed of the auxiliary unit, m / (Mm) <V a / V m ; The power generation power of a single unit is basically constant, which is the sum of the powers of m working cars; the utilization rate of the hoistway car and the drive shaft is m / M100%.

5. The operation control method of the gravity energy storage system according to claim 4, characterized in that: The ratio of the number of the working cars to the number of the empty cars is 5:1, 3:1 or 2:

1.

6. The operation control method of the gravity energy storage system according to claim 1, characterized in that: The specific method for controlling the timing coordination of load addition and reduction of multiple objects among multiple units includes: Several groups of gravity energy storage units in the gravity energy storage system are divided into grid-connected groups, each of which is provided with two gravity energy storage units; in the energy storage work control or energy release and power generation work control, the grid-connected groups are operated at intervals and the working car of one gravity energy storage unit of each grid-connected group is cut in, and the working car of the other gravity energy storage unit is cut out.

7. The operation control method of the gravity energy storage system according to claim 1, characterized in that: The gravity energy storage system is a gravity energy storage system coupled with a flywheel or a supercapacitor.

8. An operation control system of a gravity energy storage system, wherein a plurality of groups of gravity energy storage units in the gravity energy storage system are connected to the power grid in a multi-synchronous machine grid-connected mode, characterized in that: The system comprises: a startup loading determination module and a timing control module; The startup loading determination module is used to determine the gravity energy storage units that need to be started and loaded to meet the power demand of the power grid; The timing control module is used to start multiple synchronous units in a timing sequence for the determined gravity energy storage units, and adopts the timing coordination control of multiple blocks of load addition and reduction within a single unit and between multiple units.

9. An electronic device, characterized in that: The electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor is configured to call and run the computer program stored in the memory to execute the method according to any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method as claimed in any one of claims 1 to 7 are implemented.

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