Method and system for configuring energy storage device to participate in primary frequency modulation of power grid in new energy station

Abstract

The invention discloses a method and system for configuring an energy storage device to participate in primary frequency modulation of a power grid in a new energy station. The method comprises the following steps: determining operation data of the new energy station needing to configure the energy storage device to access the power grid; based on the operation data, determining a first maximum discharge power, a first capacity and a first operation strategy of a first energy storage device which needs to be configured when the new energy field station participates in primary frequency modulation to cope with power shortage of a power grid, determining a second maximum discharge power, a second capacity and a second operation strategy of a second energy storage device configured for the new energy station to participate in primary frequency modulation to cope with the power surplus of the power grid; performing simulation calculation to determine a first measurement time constant; performing simulation calculation to determine a second measurement time constant; and performing primary frequency modulation of the power grid based on the first maximum discharge power, the first capacity, the first operation strategy, the second maximum discharge power, the second capacity, the second operation strategy, the first measurement time constant and the second measurement time constant, so that the system is in a frequency stable state.

Description

Technical Field

[0001] The present invention relates to the field of electric power and electrical engineering technology, and more specifically, to a method and system for configuring an energy storage device at a new energy station to participate in primary frequency regulation of a power grid. Background Art

[0002] The frequency of the power system is determined by the speed of the conventional unit, which is expressed by the rotor motion equation

[0003]

[0004] Where J is the moment of inertia, ω is the conventional unit speed, T M , T E , T D They are mechanical torque, electromagnetic torque and damping torque respectively.

[0005] The relationship between torque, power and speed is P = Tω, so when the damping torque is ignored, the rotor motion can be written as:

[0006]

[0007] When the power system operates stably, the mechanical power P output by the generator is M The electromagnetic power P required by the system E equal, so the generator speed, that is, the system frequency, remains constant. When the system loses some power generation or load, P E Changes, P M and P E It can be seen that under the same power difference condition, the larger the moment of inertia J, the slower the frequency change speed.

[0008] When the generator speed changes, if its output mechanical power does not reach the upper or lower limit, it will change accordingly under the action of the speed governor. Figure 1 The frequency characteristic curve is shown.

[0009] It can be seen that as the frequency decreases, the generator output mechanical power increases, and the relationship can be expressed as

[0010] ΔP G =-K G Δf

[0011]

[0012] Among them, K G is the unit regulating power of the generator, and its reciprocal R is the regulation coefficient of the generator.

[0013] Since the regulation coefficients of the generators in the power grid may be different, the changes in the output mechanical power are different. In order to maintain the synchronous operation of the generators in the power grid, the electromagnetic power allocated to each generator will also change with the mechanical power output by the generator.

[0014] As the frequency increases or decreases, when the mechanical power output by the generator reaches a balance with the system electromagnetic power again, the frequency no longer changes. This process is called the primary frequency regulation process of the power system.

[0015] Since there is a deviation between the system frequency and the initial operating reference frequency after the primary frequency regulation, the system frequency is required to be readjusted to the operating reference frequency through secondary frequency regulation of the automatic generation control system AGC.

[0016] The access of new energy sources such as wind power and photovoltaic energy to the grid to replace conventional units will, on the one hand, cause the withdrawal of conventional units, reduce system inertia, and make the frequency change faster; on the other hand, new energy sources do not participate in the primary frequency regulation of the system, which reduces the primary frequency regulation capability of the grid and weakens the frequency control capability, making it more prone to frequency over-limit situations, threatening the safe and stable operation of the grid. Summary of the invention

[0017] The present invention proposes a method and system for configuring an energy storage device at a new energy station to participate in primary frequency regulation of a power grid, so as to solve the problem of how to perform primary frequency regulation of a power grid by configuring an energy storage device at a new energy station.

[0018] In order to solve the above problem, according to one aspect of the present invention, a method for configuring an energy storage device in a new energy station to participate in primary frequency regulation of a power grid is provided, the method comprising:

[0019] Determine the operation data of new energy stations that need to be equipped with energy storage devices to access the power grid;

[0020] Based on the operation data, determine a first maximum discharge power, a first capacity, and a first operation strategy of a first energy storage device that needs to be configured for the new energy station to participate in primary frequency regulation to cope with power shortage of the power grid;

[0021] Based on the operation data, determine the second maximum discharge power, the second capacity and the second operation strategy of the second energy storage device that needs to be configured when the new energy station participates in the primary frequency regulation to cope with the power surplus of the power grid;

[0022] Perform simulation calculation to determine a first measurement time constant of the first energy storage device participating in the primary frequency regulation control parameter, so that the primary frequency regulation performance of the first energy storage device satisfies the replaced conventional unit;

[0023] Perform simulation calculation to determine the second measurement time constant of the second energy storage device participating in the primary frequency regulation control parameter, so that the primary frequency regulation performance of the second energy storage device meets the requirements of the replaced conventional unit;

[0024] Based on the first maximum discharge power, the first capacity, the first operating strategy, the second maximum discharge power, the second capacity and the second operating strategy, the first measurement time constant and the second measurement time constant, the grid is frequency-regulated once to put the system in a frequency-stable state.

[0025] Preferably, the operating data includes: the rotational inertia J of the conventional unit replaced by the new energy station connected to the grid R ; Total moment of inertia J of the grid before connection and replacement T ; When the replaced conventional unit is running, the upward adjustment margin P reserved for participating in the primary frequency regulation of the power grid up and downward adjustment margin P down ; The time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation T S The maximum power imbalance that the grid needs to deal with in primary frequency regulation is the maximum power shortage P. L and the maximum power surplus P S .

[0026] Preferably, the method further comprises:

[0027] Using P dis =max[P up ,P L *(J R / J T )] determine a first maximum discharge power;

[0028] Using C dis =P dis *T S determining a first capacity;

[0029] The operation strategy of the first energy storage device is determined as follows: when the power grid is not in the primary frequency modulation process, the first energy storage device S is given priority. up Charge to full energy state. If it is already full, S up Neither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S up Switch to discharge; when the grid is in a frequency regulation process caused by power surplus, S up Switch to neither charging nor discharging;

[0030] Among them, P dis is the first maximum discharge power; P up To adjust the margin upward; P L is the maximum power shortage; J RThe rotation inertia of conventional units replaced by new energy stations connected to the grid; J T is the total moment of inertia of the power grid before connection and replacement; C dis is the first capacity; T S It is the time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation.

[0031] Preferably, the method further comprises:

[0032] Using P ch =max[P down ,P S *(J R / J T )] determine the second maximum discharge power;

[0033] Using C ch =P ch *T S determining a second capacity;

[0034] The operation strategy of the first energy storage device is determined as follows: when the power grid is not in the primary frequency modulation process, the second energy storage device S is used first. down Discharge to empty energy state, if it has been discharged, then S down Neither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S down Switch to neither charging nor discharging; when the grid is in a frequency regulation process caused by power surplus, S down Switch to charging;

[0035] Among them, P ch is the second maximum discharge power; P down To adjust the margin downward; P S is the maximum power surplus; J R The rotation inertia of conventional units replaced by new energy stations connected to the grid; J T is the total moment of inertia of the power grid before connection and replacement; C ch is the second capacity; T S It is the time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation.

[0036] Preferably, the performing of simulation calculation to determine the first measurement time constant of the first energy storage device participating in the primary frequency modulation control parameter includes:

[0037] (1) Through simulation calculation, it is found that the power shortage of the replaced conventional unit in the power grid is P L The first electromagnetic power variation curve borne when L is the maximum power shortage;

[0038] (2) Replace the conventional unit with a new energy station plus the first energy storage device S up , through simulation calculation, we get S up When the power shortage of the power grid is P L Discharge power variation curve when ;

[0039] (3) Compare the first electromagnetic power change curve and the discharge power change curve; if the slope of the discharge power change curve is equal to the slope of the first electromagnetic power change curve, determine the current time constant as the first measurement time constant; if the slope of the discharge power change curve is less than the slope of the first electromagnetic power change curve, reduce the value of the time constant and return to step (2) to recalculate; if the slope of the discharge power change curve is greater than the slope of the first electromagnetic power change curve, increase the value of the time constant and return to step (2) to recalculate.

[0040] Preferably, the performing of simulation calculation to determine the second measurement time constant of the second energy storage device participating in the primary frequency modulation control parameter includes:

[0041] (1) Through simulation calculation, the power surplus of the replaced conventional unit in the power grid is P S The second electromagnetic power variation curve borne when S is the maximum power surplus;

[0042] (2) Replace the conventional unit with a new energy station plus a second energy storage device S down , through simulation calculation, we get S down The power surplus in the grid is P S Charging power variation curve when

[0043] (3) Compare the second electromagnetic power change curve and the discharge power change curve; if the slope of the charging power change curve is equal to the slope of the second electromagnetic power change curve, determine the current time constant as the first measurement time constant; if the slope of the charging power change curve is greater than the slope of the second electromagnetic power change curve, reduce the value of the time constant and return to step (2) to recalculate; if the slope of the charging power change curve is less than the slope of the second electromagnetic power change curve, increase the value of the time constant and return to step (2) to recalculate.

[0044] According to another aspect of the present invention, a system is provided for configuring an energy storage device in a new energy station to participate in primary frequency regulation of a power grid, the system comprising:

[0045] An operation data determination unit, used to determine the operation data of a new energy station that needs to be equipped with an energy storage device and connected to the power grid;

[0046] A first parameter calculation unit, for determining, based on the operation data, a first maximum discharge power, a first capacity, and a first operation strategy of a first energy storage device that needs to be configured when the new energy station participates in primary frequency regulation to cope with power shortage of the power grid;

[0047] A second parameter calculation unit determines, based on the operation data, a second maximum discharge power, a second capacity, and a second operation strategy of a second energy storage device that needs to be configured when the new energy station participates in primary frequency regulation to cope with power surplus of the power grid;

[0048] A first measurement time constant determination unit, used for performing simulation calculation to determine a first measurement time constant in a primary frequency regulation control parameter of the first energy storage device, so that the primary frequency regulation performance of the first energy storage device satisfies the replaced conventional unit;

[0049] A second measurement time constant determination unit, used for performing simulation calculation to determine a second measurement time constant in the primary frequency regulation control parameter of the second energy storage device, so that the primary frequency regulation performance of the second energy storage device satisfies the conventional unit to be replaced;

[0050] The power grid frequency modulation unit is used to perform primary power grid frequency modulation based on the first maximum discharge power, the first capacity, the first operating strategy, the second maximum discharge power, the second capacity and the second operating strategy, the first measurement time constant and the second measurement time constant, so that the system is in a frequency stable state.

[0051] Preferably, the operating data includes: the rotational inertia J of the conventional unit replaced by the new energy station connected to the grid R ; Total moment of inertia J of the grid before connection and replacement T ; When the replaced conventional unit is running, the upward adjustment margin P reserved for participating in the primary frequency regulation of the power grid up and downward adjustment margin P down ; The time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation T S The maximum power imbalance that the grid needs to deal with in primary frequency regulation is the maximum power shortage P. L and the maximum power surplus P S .

[0052] Preferably, the first parameter calculation unit further includes:

[0053] Using P dis =max[P up ,P L *(J R / J T )] determine a first maximum discharge power;

[0054] Using C dis =P dis *TS determining a first capacity;

[0055] The operation strategy of the first energy storage device is determined as follows: when the power grid is not in the primary frequency modulation process, the first energy storage device S is given priority. up Charge to full energy state. If it is already full, S up Neither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S up Switch to discharge; when the grid is in a frequency regulation process caused by power surplus, S up Switch to neither charging nor discharging;

[0056] Among them, P dis is the first maximum discharge power; P up To adjust the margin upward; P L is the maximum power shortage; J R The rotation inertia of conventional units replaced by new energy stations connected to the grid; J T is the total moment of inertia of the power grid before connection and replacement; C dis is the first capacity; T S It is the time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation.

[0057] Preferably, the second parameter calculation unit further includes:

[0058] Using P ch =max[P down ,P S *(J R / J T )] determine the second maximum discharge power;

[0059] Using C ch =P ch *T S determining a second capacity;

[0060] The operation strategy of the first energy storage device is determined as follows: when the power grid is not in the primary frequency modulation process, the second energy storage device S is used first. down Discharge to empty energy state, if it has been discharged, then S down Neither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S down Switch to neither charging nor discharging; when the grid is in a frequency regulation process caused by power surplus, S down Switch to charging;

[0061] Among them, P ch is the second maximum discharge power; P down To adjust the margin downward; P S is the maximum power surplus; JR The rotation inertia of conventional units replaced by new energy stations connected to the grid; J T is the total moment of inertia of the power grid before connection and replacement; C ch is the second capacity; T S It is the time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation.

[0062] Preferably, the first measurement time constant determining unit performs simulation calculation to determine the first measurement time constant of the first energy storage device participating in the primary frequency modulation control parameter, including:

[0063] (1) Through simulation calculation, it is found that the power shortage of the replaced conventional unit in the power grid is P L The first electromagnetic power variation curve borne when L is the maximum power shortage;

[0064] (2) Replace the conventional unit with a new energy station plus the first energy storage device S up , through simulation calculation, we get S up When the power shortage of the power grid is P L Discharge power variation curve when ;

[0065] (3) Compare the first electromagnetic power change curve and the discharge power change curve; if the slope of the discharge power change curve is equal to the slope of the first electromagnetic power change curve, determine the current time constant as the first measurement time constant; if the slope of the discharge power change curve is less than the slope of the first electromagnetic power change curve, reduce the value of the time constant and return to step (2) to recalculate; if the slope of the discharge power change curve is greater than the slope of the first electromagnetic power change curve, increase the value of the time constant and return to step (2) to recalculate.

[0066] Preferably, the second measurement time constant determining unit performs simulation calculation to determine the second measurement time constant of the second energy storage device participating in the primary frequency modulation control parameter, including:

[0067] (1) Through simulation calculation, the power surplus of the replaced conventional unit in the power grid is P S The second electromagnetic power variation curve borne when S is the maximum power surplus;

[0068] (2) Replace the conventional unit with a new energy station plus a second energy storage device S down , through simulation calculation, we get S down The power surplus in the grid is P S Charging power variation curve when

[0069] (3) Compare the second electromagnetic power change curve and the discharge power change curve; if the slope of the charging power change curve is equal to the slope of the second electromagnetic power change curve, determine the current time constant as the first measurement time constant; if the slope of the charging power change curve is greater than the slope of the second electromagnetic power change curve, reduce the value of the time constant and return to step (2) to recalculate; if the slope of the charging power change curve is less than the slope of the second electromagnetic power change curve, increase the value of the time constant and return to step (2) to recalculate.

[0070] The present invention provides a method and system for configuring an energy storage device in a new energy station to participate in primary frequency modulation of a power grid, comprising: determining operation data of a new energy station that needs to be configured with an energy storage device to access a power grid; based on the operation data, determining a first maximum discharge power, a first capacity, and a first operation strategy of a first energy storage device that needs to be configured when the new energy station participates in primary frequency modulation to cope with power shortage of the power grid; based on the operation data, determining a second maximum discharge power, a second capacity, and a second operation strategy of a second energy storage device that needs to be configured when the new energy station participates in primary frequency modulation to cope with power surplus of the power grid; performing simulation calculations to determine a first measurement time constant in a control parameter of the first energy storage device participating in primary frequency modulation, so that the primary frequency modulation performance of the first energy storage device meets that of a conventional unit replaced; performing simulation calculations to determine a second measurement time constant in a control parameter of the second energy storage device participating in primary frequency modulation, so that the primary frequency modulation performance of the second energy storage device meets that of a conventional unit replaced; performing primary frequency modulation of the power grid based on the first maximum discharge power, the first capacity, the first operation strategy, the second maximum discharge power, the second capacity, the second operation strategy, the first measurement time constant, and the second measurement time constant, so that the system is in a frequency stable state. The present invention achieves an effect close to that of a synchronous generator of the same capacity by configuring a certain capacity of energy storage devices at new energy stations and reasonably allocating them to participate in the primary frequency regulation task of the power grid, thereby improving the frequency control capability and operating stability of the power grid with high penetration rate of new energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0072] Figure 1 It is a schematic diagram of the frequency characteristic curve of the generator;

[0073] Figure 2 A flowchart of a method 200 for configuring an energy storage device in a new energy station to participate in primary frequency regulation of a power grid according to an embodiment of the present invention;

[0074] Figure 3 A structural diagram of a power grid with access to new energy sources according to an embodiment of the present invention;

[0075] Figure 4A comparison diagram of a discharge power variation curve and an electromagnetic power variation curve according to an embodiment of the present invention;

[0076] Figure 5 A comparison diagram of grid frequency response curves under the conditions where a conventional unit participates in primary frequency regulation and an energy storage device with different measurement time constants participates in primary frequency regulation according to an embodiment of the present invention;

[0077] Figure 6 A schematic diagram of the structure of a system 600 in which a new energy station is configured with an energy storage device to participate in primary frequency regulation of a power grid according to an embodiment of the present invention. DETAILED DESCRIPTION

[0078] Now, exemplary embodiments of the present invention are described with reference to the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely and to fully convey the scope of the present invention to those skilled in the art. The terms used in the exemplary embodiments shown in the accompanying drawings are not intended to limit the present invention. In the accompanying drawings, the same units / elements are marked with the same reference numerals.

[0079] Unless otherwise specified, the terms (including technical terms) used herein have the commonly understood meanings to those skilled in the art. In addition, it is understood that the terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0080] Figure 2 A flow chart of a method 200 for configuring an energy storage device in a new energy station to participate in primary frequency regulation of a power grid according to an embodiment of the present invention. Figure 2 As shown, the method for configuring energy storage devices at new energy stations to participate in the primary frequency regulation of the power grid provided by the embodiment of the present invention achieves an effect close to that of synchronous generators of the same capacity by configuring energy storage devices of a certain capacity at the new energy stations and reasonably allocating the tasks of participating in the primary frequency regulation of the power grid, and can improve the frequency control capability and operation stability of the power grid with high penetration rate of new energy. The method 200 for configuring energy storage devices at new energy stations to participate in the primary frequency regulation of the power grid provided by the embodiment of the present invention starts from step 201. In step 201, the operation data of the new energy station that needs to be configured with energy storage devices to access the power grid is determined.

[0081] Preferably, the operating data includes: the rotational inertia J of the conventional unit replaced by the new energy station connected to the grid R ; Total moment of inertia J of the grid before connection and replacement T ; When the replaced conventional unit is running, the upward adjustment margin P reserved for participating in the primary frequency regulation of the power grid up and downward adjustment margin Pdown ; The time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation T S The maximum power imbalance that the grid needs to deal with in primary frequency regulation is the maximum power shortage P. L and the maximum power surplus P S .

[0082] In the present invention, it is first necessary to determine the new energy station that needs to be equipped with an energy storage device and various related conditions for its access to the power grid, including the following aspects:

[0083] (1) The moment of inertia J of conventional units replaced by new energy stations connected to the grid R , the total moment of inertia of the grid before connection and replacement J T .

[0084] (2) The upward adjustment margin P reserved for participating in the primary frequency regulation of the power grid when the replaced conventional unit is in operation up and downward adjustment margin P down .

[0085] (3) The time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation T S .

[0086] (4) The maximum power imbalance that the grid needs to deal with in primary frequency regulation, i.e., the maximum power deficit P L and the maximum power surplus P S .

[0087] In step 202, based on the operation data, determine the first maximum discharge power, the first capacity and the first operation strategy of the first energy storage device that needs to be configured when the new energy station participates in primary frequency regulation to cope with power shortage in the power grid.

[0088] Preferably, the method further comprises:

[0089] Using P dis =max[P up ,P L *(J R / J T )] determine a first maximum discharge power;

[0090] Using C dis =P dis *T S determining a first capacity;

[0091] The operation strategy of the first energy storage device is determined as follows: when the power grid is not in the primary frequency modulation process, the first energy storage device S is given priority. up Charge to full energy state. If it is already full, S upNeither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S up Switch to discharge; when the grid is in a frequency regulation process caused by power surplus, S up Switch to neither charging nor discharging;

[0092] Among them, P dis is the first maximum discharge power; P up To adjust the margin upward; P L is the maximum power shortage; J R The rotation inertia of conventional units replaced by new energy stations connected to the grid; J T is the total moment of inertia of the power grid before connection and replacement; C dis is the first capacity; T S It is the time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation.

[0093] In step 203, based on the operation data, determine the second maximum discharge power, second capacity and second operation strategy of the second energy storage device that needs to be configured when the new energy station participates in primary frequency regulation to cope with power surplus of the power grid.

[0094] Preferably, the method further comprises:

[0095] Using P ch =max[P down ,P S *(J R / J T )] determine the second maximum discharge power;

[0096] Using C ch =P ch *T S determining a second capacity;

[0097] The operation strategy of the first energy storage device is determined as follows: when the power grid is not in the primary frequency modulation process, the second energy storage device S is used first. down Discharge to empty energy state, if it has been discharged, then S down Neither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S down Switch to neither charging nor discharging; when the grid is in a frequency regulation process caused by power surplus, S down Switch to charging;

[0098] Among them, P ch is the second maximum discharge power; P down To adjust the margin downward; P S is the maximum power surplus; J R The rotation inertia of conventional units replaced by new energy stations connected to the grid; JT is the total moment of inertia of the power grid before connection and replacement; C ch is the second capacity; T S It is the time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation.

[0099] In the present invention, it is also necessary to determine the energy storage device S that needs to be configured for the new energy station to participate in the primary frequency regulation to cope with the power shortage of the power grid. up Maximum discharge power P dis , Capacity C dis And operation strategies are as follows:

[0100] (1) Determine S up Maximum discharge power P dis =max[P up ,P L *(J R / J T )];

[0101] (2) Determine S up Capacity C dis =P dis *T S ;

[0102] (3) Determine S up The operation strategy is: when the power grid is not in the process of primary frequency regulation, priority is given to S up Charge to full energy state. If it is already full, S up Neither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S up Switch to discharge; when the grid is in a frequency regulation process caused by power surplus, S up Switches to neither charging nor discharging.

[0103] In the present invention, it is also necessary to determine the energy storage device S that needs to be configured when the new energy station participates in the primary frequency regulation to cope with the power surplus of the power grid. down Maximum discharge power P ch , Capacity C ch And operation strategies are as follows:

[0104] (1) Determine S down Maximum discharge power P ch =max[P down ,P S *(J R / J T )];

[0105] (2) Determine S down Capacity C ch =P ch *T S ;

[0106] (3) Determine S down The operation strategy is: when the power grid is not in the primary frequency regulation process, S down Discharge to empty energy state, if it has been discharged, then S down Neither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S down Switch to neither charging nor discharging; when the grid is in a frequency regulation process caused by power surplus, S down Switch to Charging.

[0107] In step 204, simulation calculation is performed to determine a first measurement time constant of the first energy storage device participating in the primary frequency regulation control parameter, so that the primary frequency regulation performance of the first energy storage device satisfies the replaced conventional unit.

[0108] Preferably, the performing of simulation calculation to determine the first measurement time constant of the first energy storage device participating in the primary frequency modulation control parameter includes:

[0109] (1) Through simulation calculation, it is found that the power shortage of the replaced conventional unit in the power grid is P L The first electromagnetic power variation curve borne when L is the maximum power shortage;

[0110] (2) Replace the conventional unit with a new energy station plus the first energy storage device S up , through simulation calculation, we get S up When the power shortage of the power grid is P L Discharge power variation curve when ;

[0111] (3) Compare the first electromagnetic power change curve and the discharge power change curve; if the slope of the discharge power change curve is equal to the slope of the first electromagnetic power change curve, determine the current time constant as the first measurement time constant; if the slope of the discharge power change curve is less than the slope of the first electromagnetic power change curve, reduce the value of the time constant and return to step (2) to recalculate; if the slope of the discharge power change curve is greater than the slope of the first electromagnetic power change curve, increase the value of the time constant and return to step (2) to recalculate.

[0112] In step 205, simulation calculation is performed to determine the second measurement time constant of the second energy storage device participating in the primary frequency regulation control parameter, so that the primary frequency regulation performance of the second energy storage device satisfies the replaced conventional unit.

[0113] Preferably, the performing of simulation calculation to determine the second measurement time constant of the second energy storage device participating in the primary frequency modulation control parameter includes:

[0114] (1) Through simulation calculation, the power surplus of the replaced conventional unit in the power grid is P S The second electromagnetic power variation curve borne when S is the maximum power surplus;

[0115] (2) Replace the conventional unit with a new energy station plus a second energy storage device S down , through simulation calculation, we get S down The power surplus in the grid is P S Charging power variation curve when

[0116] (3) Compare the second electromagnetic power change curve and the discharge power change curve; if the slope of the charging power change curve is equal to the slope of the second electromagnetic power change curve, determine the current time constant as the first measurement time constant; if the slope of the charging power change curve is greater than the slope of the second electromagnetic power change curve, reduce the value of the time constant and return to step (2) to recalculate; if the slope of the charging power change curve is less than the slope of the second electromagnetic power change curve, increase the value of the time constant and return to step (2) to recalculate.

[0117] In the present invention, the energy storage device S is determined up The measured time constant T in the primary frequency modulation control parameter RF , so that the primary frequency regulation performance of the energy storage device is close to that of the conventional unit it replaces, as follows:

[0118] (1) Through simulation calculation, the power shortage of the replaced conventional unit in the power grid is obtained as P L The change curve of electromagnetic power borne when

[0119] (2) Replace conventional units with new energy stations and energy storage devices S up , through simulation calculation, we get S up When the power shortage of the power grid is P L Discharge power variation curve when ;

[0120] (3) Comparing the simulation curves obtained in (1) and (2), if the slope of the discharge power change curve is smaller than the electromagnetic power change curve, then reduce T RF If the slope of the discharge power curve is greater than that of the electromagnetic power curve, increase T RF The value of

[0121] Then, (2) is repeated until the slope of the discharge power variation curve is equal to the electromagnetic power variation curve.

[0122] In the present invention, the energy storage device S is determined down The measured time constant T in the primary frequency modulation control parameterRF , so that the primary frequency regulation performance of the energy storage device is close to that of the conventional unit it replaces, as follows:

[0123] (1) Through simulation calculation, the power surplus of the replaced conventional unit in the power grid is obtained as P S The electromagnetic power variation curve when borne;

[0124] (2) Replace conventional units with new energy stations and energy storage devices S down , through simulation calculation, we get S down The power surplus in the grid is P S Charging power variation curve when

[0125] (3) Comparing the simulation curves obtained in (1) and (2), if the slope of the charging power change curve is greater than the electromagnetic power change curve, then reduce T RF If the slope of the charging power curve is smaller than that of the electromagnetic power curve, increase T RF Value

[0126] Then, repeat (2) until the slope of the charging power variation curve is equal to the electromagnetic power variation curve.

[0127] In step 206, the grid is frequency-regulated based on the first maximum discharge power, the first capacity, the first operation strategy, the second maximum discharge power, the second capacity, the second operation strategy, the first measurement time constant and the second measurement time constant to stabilize the system frequency.

[0128] The present invention configures energy storage devices with appropriate power and capacity at new energy stations and reasonably sets their operating strategies and control parameters, so that the overall new energy stations can reach a level close to the primary frequency regulation capability of the conventional units they replace, thereby improving the frequency control capability and operating stability of the new energy high-penetration power grid.

[0129] The following takes a specific calculation system as an example to illustrate the implementation process and results of this method.

[0130] like Figure 3 The figure shows a structure diagram of a power grid with access to new energy. Figure 3 The middle busbars 30, 32, 33, 34, 36, 37 and 39 are conventional generators, and busbar 35 is the access point for the new energy station.

[0131] The conventional generators on busbars 30, 32, 33, 34, 36, 37 and 39 are respectively recorded as G1, G2, G3, G4, G5, G6 and G7. Now, as the new energy station is connected from busbar 35, generator G7 is ready to be withdrawn.

[0132] The moment of inertia of generator G7 is 5×10 4kg·m 2 , the total moment of inertia of the system before G7 exits is 1×10 6 kg·m 2 .

[0133] The upward adjustment margin of generator G7 participating in the primary frequency regulation of the power grid is 5MW, and the downward adjustment margin is 0MW.

[0134] The maximum power deficit that the primary frequency regulation of the power grid needs to deal with is 30MW, and the maximum power surplus is 0MW; the time from the occurrence of power imbalance to the intervention of secondary frequency regulation is 180 seconds.

[0135] Based on the above data, we can get:

[0136] P dis =max[P up ,P L *(J R / J T )]=max[5,30*5 / 100]=5MW

[0137] C dis =P dis *T S =5MW*180s=250kWh

[0138] P ch =max[P down ,P S *(J R / J T )]=max[0,0]=0

[0139] C ch =P ch *T S =0

[0140] That is, configure S up The maximum discharge power is 5MW and the capacity is 250kWh; no S down .

[0141] By comparing the simulation curves, determine S up The measured time constant T in the primary frequency modulation control parameter RF .Depend on Figure 4 It can be seen that when T RF When =0.4, the slope of the discharge power curve is the same as that of the electromagnetic power curve.

[0142] At this point, the entire configuration of the energy storage device is completed.

[0143] Compare the frequency response curves of G7 not exiting and using energy storage devices to replace G7 to participate in primary frequency regulation when the maximum power shortage of the power grid is 30MW. Figure 5 As shown, it can be seen that the lowest frequency value of the power grid is basically the same during the primary frequency regulation process. When the energy storage device is used to replace G7 to participate in the primary frequency regulation, the power grid frequency recovers faster and the recovered frequency value is higher.

[0144] In addition, from Figure 4 and Figure 5 It can be seen that if T RF When it decreases to 0.1, the slope of the discharge power curve is greater than that of the electromagnetic power curve. The minimum frequency value of the power grid increases during the primary frequency modulation process, and the frequency recovery speed and recovery value are better. However, T RF Too small may cause the energy storage device to oscillate. Therefore, it is recommended to set T RF Reduce it until the slope of the discharge power curve is the same as that of the electromagnetic power curve, and maintain the primary frequency regulation performance close to that of a conventional unit.

[0145] Figure 6 The structure diagram of the system 600 for configuring an energy storage device in a new energy station to participate in the primary frequency regulation of the power grid according to an embodiment of the present invention is shown. Figure 6 As shown, a system 600 for a new energy station configured with an energy storage device to participate in primary frequency regulation of a power grid provided in an embodiment of the present invention includes: an operation data determination unit 601, a first parameter calculation unit 602, a second parameter calculation unit 603, a first measurement time constant determination unit 604, a second measurement time constant determination unit 605 and a power grid frequency regulation unit 606.

[0146] Preferably, the operation data determination unit 601 is used to determine the operation data of the new energy station that needs to be equipped with an energy storage device to access the power grid.

[0147] Preferably, the operating data includes: the rotational inertia J of the conventional unit replaced by the new energy station connected to the grid R ; Total moment of inertia J of the grid before connection and replacement T ; When the replaced conventional unit is running, the upward adjustment margin P reserved for participating in the primary frequency regulation of the power grid up and downward adjustment margin P down ; The time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation T S The maximum power imbalance that the grid needs to deal with in primary frequency regulation is the maximum power shortage P. L and the maximum power surplus P S .

[0148] Preferably, the first parameter calculation unit 602 is used to determine, based on the operation data, a first maximum discharge power, a first capacity and a first operation strategy of a first energy storage device that needs to be configured when the new energy station participates in primary frequency regulation to cope with power shortage in the power grid.

[0149] Preferably, the first parameter calculation unit 602 further includes:

[0150] Using P dis =max[P up ,P L *(J R / J T )] determine a first maximum discharge power;

[0151] Using C dis =P dis *T S determining a first capacity;

[0152] The operation strategy of the first energy storage device is determined as follows: when the power grid is not in the primary frequency modulation process, the first energy storage device S is given priority. up Charge to full energy state. If it is already full, S up Neither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S up Switch to discharge; when the grid is in a frequency regulation process caused by power surplus, S up Switch to neither charging nor discharging;

[0153] Among them, P dis is the first maximum discharge power; P up To adjust the margin upward; P L is the maximum power shortage; J R The rotation inertia of conventional units replaced by new energy stations connected to the grid; J T is the total moment of inertia of the power grid before connection and replacement; C dis is the first capacity; T S It is the time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation.

[0154] Preferably, the second parameter calculation unit 603 is used to determine, based on the operation data, the second maximum discharge power, the second capacity and the second operation strategy of the second energy storage device that needs to be configured when the new energy station participates in primary frequency regulation to cope with power surplus of the power grid.

[0155] Preferably, the second parameter calculation unit 603 further includes:

[0156] Using P ch =max[P down ,P S *(J R / J T )] determine the second maximum discharge power;

[0157] Using C ch =P ch *T Sdetermining a second capacity;

[0158] The operation strategy of the first energy storage device is determined as follows: when the power grid is not in the primary frequency modulation process, the second energy storage device S is used first. down Discharge to empty energy state, if it has been discharged, then S down Neither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S down Switch to neither charging nor discharging; when the grid is in a frequency regulation process caused by power surplus, S down Switch to charging;

[0159] Among them, P ch is the second maximum discharge power; P down To adjust the margin downward; P S is the maximum power surplus; J R The rotation inertia of conventional units replaced by new energy stations connected to the grid; J T is the total moment of inertia of the power grid before connection and replacement; C ch is the second capacity; T S It is the time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation.

[0160] Preferably, the first measurement time constant determination unit 604 is used to perform simulation calculations to determine the first measurement time constant of the first energy storage device participating in the primary frequency regulation control parameters, so that the primary frequency regulation performance of the first energy storage device meets the requirements of the replaced conventional unit.

[0161] Preferably, the first measurement time constant determining unit 604 performs simulation calculation to determine the first measurement time constant of the first energy storage device participating in the primary frequency modulation control parameter, including:

[0162] (1) Through simulation calculation, it is found that the power shortage of the replaced conventional unit in the power grid is P L The first electromagnetic power variation curve borne when L is the maximum power shortage;

[0163] (2) Replace the conventional unit with a new energy station plus the first energy storage device S up , through simulation calculation, we get S up When the power shortage of the power grid is P L Discharge power variation curve when ;

[0164] (3) Compare the first electromagnetic power change curve and the discharge power change curve; if the slope of the discharge power change curve is equal to the slope of the first electromagnetic power change curve, determine the current time constant as the first measurement time constant; if the slope of the discharge power change curve is less than the slope of the first electromagnetic power change curve, reduce the value of the time constant and return to step (2) to recalculate; if the slope of the discharge power change curve is greater than the slope of the first electromagnetic power change curve, increase the value of the time constant and return to step (2) to recalculate.

[0165] Preferably, the second measurement time constant determination unit 605 is used to perform simulation calculations to determine the second measurement time constant of the second energy storage device participating in the primary frequency regulation control parameters, so that the primary frequency regulation performance of the second energy storage device meets the requirements of the replaced conventional unit.

[0166] Preferably, the second measurement time constant determining unit 605 performs simulation calculation to determine the second measurement time constant of the second energy storage device participating in the primary frequency modulation control parameter, including:

[0167] (1) Through simulation calculation, the power surplus of the replaced conventional unit in the power grid is P S The second electromagnetic power variation curve borne when S is the maximum power surplus;

[0168] (2) Replace the conventional unit with a new energy station plus a second energy storage device S down , through simulation calculation, we get S down The power surplus in the grid is P S Charging power variation curve when

[0169] (3) Compare the second electromagnetic power change curve and the discharge power change curve; if the slope of the charging power change curve is equal to the slope of the second electromagnetic power change curve, determine the current time constant as the first measurement time constant; if the slope of the charging power change curve is greater than the slope of the second electromagnetic power change curve, reduce the value of the time constant and return to step (2) to recalculate; if the slope of the charging power change curve is less than the slope of the second electromagnetic power change curve, increase the value of the time constant and return to step (2) to recalculate.

[0170] Preferably, the grid frequency regulation unit 606 is used to perform primary grid frequency regulation based on the first maximum discharge power, the first capacity, the first operating strategy, the second maximum discharge power, the second capacity and the second operating strategy, the first measurement time constant and the second measurement time constant, so that the system is in a frequency stable state.

[0171] The system 600 for configuring energy storage devices at new energy stations to participate in primary frequency regulation of a power grid in an embodiment of the present invention corresponds to the method 200 for configuring energy storage devices at new energy stations to participate in primary frequency regulation of a power grid in another embodiment of the present invention, and will not be described in detail here.

[0172] The present invention has been described with reference to a few embodiments. However, it is known to those skilled in the art that other embodiments than the one disclosed above are equally within the scope of the present invention.

[0173] Generally, all terms used in the present invention are interpreted according to their ordinary meaning in the technical field, unless otherwise explicitly defined therein. All references to "a / said / the [device, component, etc.]" are open to interpretation as at least one instance of the device, component, etc., unless otherwise explicitly stated. The steps of any method disclosed herein do not necessarily have to be performed in the exact order disclosed, unless explicitly stated.

[0174] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0175] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0176] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0177] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0178] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for configuring an energy storage device at a new energy station to participate in primary frequency modulation of a power grid, characterized in that: The method comprises: Determine the operation data of new energy stations that need to be equipped with energy storage devices to access the power grid; Based on the operation data, determine a first maximum discharge power, a first capacity, and a first operation strategy of a first energy storage device that needs to be configured for the new energy station to participate in primary frequency regulation to cope with power shortage of the power grid; Based on the operation data, determine the second maximum discharge power, the second capacity and the second operation strategy of the second energy storage device that needs to be configured when the new energy station participates in the primary frequency regulation to cope with the power surplus of the power grid; Perform simulation calculation to determine a first measurement time constant of the first energy storage device participating in the primary frequency regulation control parameter, so that the primary frequency regulation performance of the first energy storage device satisfies the replaced conventional unit; Perform simulation calculation to determine the second measurement time constant of the second energy storage device participating in the primary frequency regulation control parameter, so that the primary frequency regulation performance of the second energy storage device meets the requirements of the replaced conventional unit; Based on the first maximum discharge power, the first capacity, the first operating strategy, the second maximum discharge power, the second capacity and the second operating strategy, the first measurement time constant and the second measurement time constant, the grid is frequency-regulated once to put the system in a frequency-stable state.

2. The method according to claim 1, characterized in that The operating data include: the rotational inertia J of the conventional units replaced by the new energy station connected to the grid R ; Total moment of inertia J of the grid before connection and replacement T ; When the replaced conventional unit is running, the upward adjustment margin P reserved for participating in the primary frequency regulation of the power grid up and downward adjustment margin P down ; The time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation T S The maximum power imbalance that the grid needs to deal with in primary frequency regulation is the maximum power shortage P. L and the maximum power surplus P S .

3. The method according to claim 1, characterized in that: The method further comprises: Using P dis =max[P up ,P L *(J R / J T )] determine a first maximum discharge power; Using C dis =P dis *T S determining a first capacity; The operation strategy of the first energy storage device is determined as follows: when the power grid is not in the primary frequency modulation process, the first energy storage device S is given priority. up Charge to full energy state. If it is already full, S up Neither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S up Switch to discharge; when the grid is in a frequency regulation process caused by power surplus, S up Switch to neither charging nor discharging; Among them, P dis is the first maximum discharge power; P up To adjust the margin upward; P L is the maximum power shortage; J R The rotation inertia of conventional units replaced by new energy stations connected to the grid; J T is the total moment of inertia of the power grid before connection and replacement; C dis is the first capacity; T S It is the time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation.

4. The method according to claim 1, characterized in that The method further comprises: Using P ch =max[P down ,P S *(J R / J T )] determine the second maximum discharge power; Using C ch =P ch *T S determining a second capacity; The operation strategy of the first energy storage device is determined as follows: when the power grid is not in the primary frequency modulation process, the second energy storage device S is used first. down Discharge to empty energy state, if it has been discharged, then S down Neither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S down Switch to neither charging nor discharging; when the grid is in a frequency regulation process caused by power surplus, S down Switch to charging; Among them, P ch is the second maximum discharge power; P down To adjust the margin downward; P S is the maximum power surplus; J R The rotation inertia of conventional units replaced by new energy stations connected to the grid; J T is the total moment of inertia of the power grid before connection and replacement; C ch is the second capacity; T S It is the time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation.

5. The method according to claim 1, characterized in that The performing simulation calculation to determine a first measurement time constant of a frequency modulation control parameter in which the first energy storage device participates includes: (1) Through simulation calculation, it is found that the power shortage of the replaced conventional unit in the power grid is P L The first electromagnetic power variation curve borne when L is the maximum power shortage; (2) Replace the conventional unit with a new energy station plus the first energy storage device S up , through simulation calculation, we get S up When the power shortage of the power grid is P L Discharge power variation curve when ; (3) Compare the first electromagnetic power change curve and the discharge power change curve; if the slope of the discharge power change curve is equal to the slope of the first electromagnetic power change curve, determine the current time constant as the first measurement time constant; if the slope of the discharge power change curve is less than the slope of the first electromagnetic power change curve, reduce the value of the time constant and return to step (2) to recalculate; if the slope of the discharge power change curve is greater than the slope of the first electromagnetic power change curve, increase the value of the time constant and return to step (2) to recalculate.

6. The method according to claim 1, characterized in that The performing simulation calculation to determine the second measurement time constant of the second energy storage device participating in the primary frequency modulation control parameter includes: (1) Through simulation calculation, the power surplus of the replaced conventional unit in the power grid is P S The second electromagnetic power variation curve borne when S is the maximum power surplus; (2) Replace the conventional unit with a new energy station plus a second energy storage device S down , through simulation calculation, we get S down The power surplus in the grid is P S Charging power variation curve when (3) Compare the second electromagnetic power change curve and the discharge power change curve; if the slope of the charging power change curve is equal to the slope of the second electromagnetic power change curve, determine the current time constant as the first measurement time constant; if the slope of the charging power change curve is greater than the slope of the second electromagnetic power change curve, reduce the value of the time constant and return to step (2) to recalculate; if the slope of the charging power change curve is less than the slope of the second electromagnetic power change curve, increase the value of the time constant and return to step (2) to recalculate.

7. A system in which a new energy station is equipped with an energy storage device to participate in primary frequency modulation of a power grid, characterized in that: The system comprises: An operation data determination unit, used to determine the operation data of a new energy station that needs to be equipped with an energy storage device and connected to the power grid; A first parameter calculation unit, for determining, based on the operation data, a first maximum discharge power, a first capacity, and a first operation strategy of a first energy storage device that needs to be configured when the new energy station participates in primary frequency regulation to cope with power shortage of the power grid; A second parameter calculation unit determines, based on the operation data, a second maximum discharge power, a second capacity, and a second operation strategy of a second energy storage device that needs to be configured when the new energy station participates in primary frequency regulation to cope with power surplus of the power grid; A first measurement time constant determination unit, used for performing simulation calculation to determine a first measurement time constant in a primary frequency regulation control parameter of the first energy storage device, so that the primary frequency regulation performance of the first energy storage device satisfies the replaced conventional unit; A second measurement time constant determination unit, used for performing simulation calculation to determine a second measurement time constant in the primary frequency regulation control parameter of the second energy storage device, so that the primary frequency regulation performance of the second energy storage device satisfies the conventional unit to be replaced; The power grid frequency modulation unit is used to perform primary power grid frequency modulation based on the first maximum discharge power, the first capacity, the first operating strategy, the second maximum discharge power, the second capacity and the second operating strategy, the first measurement time constant and the second measurement time constant, so that the system is in a frequency stable state.

8. The system according to claim 7, characterized in that The operating data include: the rotational inertia J of the conventional units replaced by the new energy station connected to the grid R ; Total moment of inertia J of the grid before connection and replacement T ; When the replaced conventional unit is running, the upward adjustment margin P reserved for participating in the primary frequency regulation of the power grid up and downward adjustment margin P down ; The time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation T S The maximum power imbalance that the grid needs to deal with in primary frequency regulation is the maximum power shortage P. L and the maximum power surplus P S .

9. The system according to claim 7, characterized in that The first parameter calculation unit further includes: Using P dis =max[P up ,P L *(J R / J T )] determine a first maximum discharge power; Using C dis =P dis *T S determining a first capacity; The operation strategy of the first energy storage device is determined as follows: when the power grid is not in the primary frequency modulation process, the first energy storage device S is given priority. up Charge to full energy state. If it is already full, S up Neither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S up Switch to discharge; when the grid is in a frequency regulation process caused by power surplus, S up Switch to neither charging nor discharging; Among them, P dis is the first maximum discharge power; P up To adjust the margin upward; P L is the maximum power shortage; J R The rotation inertia of conventional units replaced by new energy stations connected to the grid; J T is the total moment of inertia of the power grid before connection and replacement; C dis is the first capacity; T S It is the time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation.

10. The system according to claim 7, characterized in that The second parameter calculation unit further includes: Using P ch =max[P down ,P S *(J R / J T )] determine the second maximum discharge power; Using C ch =P ch *T S determining a second capacity; The operation strategy of the first energy storage device is determined as follows: when the power grid is not in the primary frequency modulation process, the second energy storage device S is used first. down Discharge to empty energy state, if it has been discharged, then S down Neither charging nor discharging; when the power grid is in a frequency regulation process caused by power shortage, S down Switch to neither charging nor discharging; when the grid is in a frequency regulation process caused by power surplus, S down Switch to charging; Among them, P ch is the second maximum discharge power; P down To adjust the margin downward; P S is the maximum power surplus; J R The rotation inertia of conventional units replaced by new energy stations connected to the grid; J T is the total moment of inertia of the power grid before connection and replacement; C ch is the second capacity; T S It is the time required from the occurrence of power imbalance in the power grid to the intervention of secondary frequency regulation.

11. The system according to claim 7, characterized in that The first measurement time constant determination unit performs simulation calculation to determine the first measurement time constant of the first energy storage device participating in the primary frequency modulation control parameter, including: (1) Through simulation calculation, it is found that the power shortage of the replaced conventional unit in the power grid is P L The first electromagnetic power variation curve borne when L is the maximum power shortage; (2) Replace the conventional unit with a new energy station plus the first energy storage device S up , through simulation calculation, we get S up When the power shortage of the power grid is P L Discharge power variation curve when ; (3) Compare the first electromagnetic power change curve and the discharge power change curve; if the slope of the discharge power change curve is equal to the slope of the first electromagnetic power change curve, determine the current time constant as the first measurement time constant; if the slope of the discharge power change curve is less than the slope of the first electromagnetic power change curve, reduce the value of the time constant and return to step (2) to recalculate; if the slope of the discharge power change curve is greater than the slope of the first electromagnetic power change curve, increase the value of the time constant and return to step (2) to recalculate.

12. The system according to claim 7, characterized in that The second measurement time constant determination unit performs simulation calculation to determine the second measurement time constant of the second energy storage device participating in the primary frequency modulation control parameter, including: (1) Through simulation calculation, the power surplus of the replaced conventional unit in the power grid is P S The second electromagnetic power variation curve borne when S is the maximum power surplus; (2) Replace the conventional unit with a new energy station plus a second energy storage device S down , through simulation calculation, we get S down The power surplus in the grid is P S Charging power variation curve when (3) Compare the second electromagnetic power change curve and the discharge power change curve; if the slope of the charging power change curve is equal to the slope of the second electromagnetic power change curve, determine the current time constant as the first measurement time constant; if the slope of the charging power change curve is greater than the slope of the second electromagnetic power change curve, reduce the value of the time constant and return to step (2) to recalculate; if the slope of the charging power change curve is less than the slope of the second electromagnetic power change curve, increase the value of the time constant and return to step (2) to recalculate.

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