Method and system for determining unit startup capacity based on DC blocking frequency constraint

Abstract

The present invention discloses a method and system for determining the startup capacity of a unit based on DC blocking frequency constraints, comprising: determining parameter equivalent data corresponding to a single-unit model based on the equivalent values ​​of parameter data and load parameter data of each unit in the system; determining the startup capacity of a first unit based on the parameter equivalent data and the maximum allowable frequency deviation; determining the startup capacity of a second unit based on the power limit ratio of the generator's primary frequency regulation and the maximum allowable frequency deviation; and determining the minimum startup capacity of the unit based on the maximum value of the startup capacity of the first unit and the startup capacity of the second unit. The present invention takes into account the primary frequency regulation constraint of the generator, can quickly assess the minimum startup capacity required by the system under a DC blocking fault, and can effectively improve the level of new energy acceptance.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and more particularly to a method and system for determining the startup capacity of a generator set based on DC blocking frequency constraints. Background Art

[0002] Compared to traditional power systems, large-scale renewable energy integration in power systems with a high proportion of power electronics has replaced some synchronous generators. The power electronic decoupling characteristics of renewable energy generators and their maximum power point tracking (MPPT) mode have gradually reduced system inertia and weakened frequency regulation capabilities. Furthermore, the introduction of ultra-high voltage, high-capacity, interregional direct current transmission (HVDC) has disrupted interregional inertia support and power response under disturbances, significantly deteriorating system frequency stability under large disturbances.

[0003] Transient frequency deviation is a key indicator of frequency stability. It occurs when the system's power generation and load first regain balance after a power surge. With the construction of ultra-high voltage AC / DC transmission projects, large-scale DC power has been connected to the grid. If a DC line experiences one or more commutation failures, the DC system will temporarily shut down and then restart. If commutation failures occur again during restart, the DC system will be locked again. This blocking of the DC system creates a permanent power imbalance between the sending and receiving ends. If a large proportion of renewable energy is connected, system inertia and primary frequency regulation capabilities will be weakened, causing transient frequency deviations to exceed the constraint.

[0004] Therefore, it is necessary to study a method for determining the unit startup capacity based on DC blocking frequency constraints. Summary of the Invention

[0005] The present invention proposes a method and system for determining the startup capacity of a unit based on DC blocking frequency constraints, so as to solve the problem of determining the minimum startup capacity of a unit constrained by the maximum frequency deviation under a DC blocking fault.

[0006] In order to solve the above problem, according to one aspect of the present invention, a method for determining the startup capacity of a unit based on DC blocking frequency constraints is provided, the method comprising:

[0007] Based on the parameter data and load parameter data of each unit in the system, the parameter equivalent data corresponding to the single unit model is determined;

[0008] Determining the startup capacity of the first unit based on the parameter equivalent data and the maximum allowable frequency deviation;

[0009] Determining the startup capacity of the second unit based on the generator primary frequency regulation power limit ratio and the maximum allowable frequency deviation;

[0010] The minimum startup capacity of the unit is determined based on the maximum value of the first unit startup capacity and the second unit startup capacity.

[0011] Preferably, the determining the startup capacity of the first unit based on the parameter equivalent data and the maximum allowable frequency deviation comprises:

[0012] ,

[0013] ,

[0014] ,

[0015] ,

[0016] ,

[0017] ,

[0018] ,

[0019] ,

[0020] ,

[0021] ,

[0022] Among them, the above formulas are solved simultaneously to determine the startup capacity P of the first unit Gmin1 ; is the maximum allowable frequency deviation; t m is the time when the maximum frequency deviation occurs; is the damping ratio; is the natural oscillation angular frequency; α and is an intermediate variable; is the disturbance power; P L is the load power; T R is the equivalent value of the unit reheater time; F H is the equivalent value of the high-pressure cylinder power ratio; P L is the load power; R is the selected reference value, which is the generator startup capacity P Gmin1 The speed gain per unit value when H is the selected reference value is the generator startup capacity P Gmin1 The inertia time constant per unit value when D is the selected reference value is the load power P L The load damping coefficient per unit value when D * 、H * 、R * and To unify the reference values ​​to the same reference capacity S N The per-unit value below.

[0023] Preferably, the determining the startup capacity of the second unit based on the generator primary frequency regulation power limit ratio and the maximum allowable frequency deviation includes:

[0024] ,

[0025] Among them, P Gmin2 The startup capacity of the second unit; is the disturbance power; D is the load damping coefficient; is the maximum allowable frequency deviation; p is the power limit ratio of the generator primary frequency regulation.

[0026] Preferably, the method further comprises:

[0027] Determining the maximum access capacity of new energy sources based on the minimum startup capacity includes:

[0028] ,

[0029] Among them, P new is the maximum access capacity of new energy; P L is the load power; k is the preset generator output ratio; P Gmin It is the minimum starting capacity of the unit.

[0030] According to another aspect of the present invention, a system for determining unit startup capacity based on DC blocking frequency constraints is provided, the system comprising:

[0031] The equivalent unit is used to determine the parameter equivalent data corresponding to the single-machine model based on the parameter data and load parameter data of each unit in the system;

[0032] A first unit startup capacity determination unit, configured to determine the first unit startup capacity based on the parameter equivalent data and a maximum frequency allowable deviation;

[0033] A second unit startup capacity determination unit, configured to determine the second unit startup capacity based on the generator primary frequency regulation power limit ratio and the maximum allowable frequency deviation;

[0034] The minimum startup capacity determination unit is used to determine the minimum startup capacity of the unit based on the maximum value of the first unit startup capacity and the second unit startup capacity.

[0035] Preferably, the first unit startup capacity determination unit determines the first unit startup capacity based on the parameter equivalent data and the maximum allowable frequency deviation, including:

[0036] ,

[0037] ,

[0038] ,

[0039] ,

[0040] ,

[0041] ,

[0042] ,

[0043] ,

[0044] ,

[0045] ,

[0046] Among them, the above formulas are solved simultaneously to determine the startup capacity P of the first unit Gmin1 ; is the maximum allowable frequency deviation; t m is the time when the maximum frequency deviation occurs; is the damping ratio; is the natural oscillation angular frequency; α and is an intermediate variable; is the disturbance power; P L is the load power; T R is the equivalent value of the unit reheater time; F H is the equivalent value of the high-pressure cylinder power ratio; P L is the load power; R is the selected reference value, which is the generator startup capacity P Gmin1 The speed gain per unit value when H is the selected reference value is the generator startup capacity P Gmin1 The inertia time constant per unit value when D is the selected reference value is the load power P L The load damping coefficient per unit value when D * 、H * 、R * and To unify the reference values ​​to the same reference capacity S N The per-unit value below.

[0047] Preferably, the second unit startup capacity determination unit determines the second unit startup capacity based on the generator primary frequency regulation power limit ratio and the maximum allowable frequency deviation, including:

[0048] ,

[0049] Among them, P Gmin2 The startup capacity of the second unit; is the disturbance power; D is the load damping coefficient; is the maximum allowable frequency deviation; p is the power limit ratio of the generator primary frequency regulation.

[0050] Preferably, the system further comprises:

[0051] A maximum access capacity determination unit is configured to determine the maximum access capacity of the new energy source based on the minimum startup capacity, including:

[0052] ,

[0053] Among them, P new is the maximum access capacity of new energy; P L is the load power; k is the preset generator output ratio; P Gmin It is the minimum starting capacity of the unit.

[0054] According to another aspect of the present invention, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any step of a method for determining the startup capacity of a unit based on DC blocking frequency constraints.

[0055] According to another aspect of the present invention, the present invention provides an electronic device, including:

[0056] The computer-readable storage medium described above; and

[0057] One or more processors are configured to execute the program in the computer-readable storage medium.

[0058] The present invention provides a method and system for determining the startup capacity of a unit based on a DC locking frequency constraint, comprising: determining parameter equivalent data corresponding to a single-unit model based on the equivalent value of parameter data and load parameter data of each unit in the system; determining the startup capacity of the first unit based on the parameter equivalent data and the maximum allowable frequency deviation; determining the startup capacity of the second unit based on the ratio of the primary frequency regulation power limit of the generator and the maximum allowable frequency deviation; and determining the minimum startup capacity of the unit based on the maximum value of the startup capacity of the first unit and the startup capacity of the second unit. The present invention uses the maximum frequency operation deviation as a constraint, determines the startup capacity of the first unit and the startup capacity of the second unit respectively in different ways, and selects the maximum value as the minimum startup capacity of the unit. The present invention takes the primary frequency regulation limit constraint of the generator into consideration, can quickly evaluate the minimum startup capacity required by the system under a DC locking fault, and can effectively improve the level of new energy acceptance. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0060] Figure 1 Flowchart of a method 100 for determining unit startup capacity based on DC blocking frequency constraint according to an embodiment of the present invention;

[0061] Figure 2 A graph showing changes in the critical access ratio of new energy plus DC when the load damping coefficient is changed according to an embodiment of the present invention;

[0062] Figure 3 This is a diagram showing changes in the critical access ratio of new energy plus DC when the disturbance power size is changed according to an embodiment of the present invention;

[0063] Figure 4 A diagram showing changes in the critical access ratio of new energy plus DC when frequency constraints are changed according to an embodiment of the present invention;

[0064] Figure 5 2 is a structural diagram of a system 500 for determining unit startup capacity based on DC blocking frequency constraints according to an embodiment of the present invention. DETAILED DESCRIPTION

[0065] Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to provide a thorough and complete disclosure of the present invention and to fully convey the scope of the present invention to those skilled in the art. The terminology used in the exemplary embodiments shown in the accompanying drawings is not intended to limit the present invention. In the accompanying drawings, identical elements are denoted by the same reference numerals.

[0066] Unless otherwise specified, the terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have meanings consistent with the context of their relevant fields and should not be interpreted as idealized or overly formal.

[0067] Figure 1 FIG. 1 is a flow chart of a method 100 for determining the startup capacity of a generator set based on DC blocking frequency constraints according to an embodiment of the present invention. Figure 1As shown, the method for determining unit operating capacity based on DC blocking frequency constraints provided by an embodiment of the present invention uses the maximum frequency operating deviation as a constraint, determines the operating capacity of the first unit and the operating capacity of the second unit through different methods, and selects the maximum value as the minimum operating capacity of the unit. Taking into account the primary frequency regulation limit constraint of the generator, this method can quickly assess the minimum operating capacity required by the system under a DC blocking fault, effectively improving the level of renewable energy acceptance. The method 100 for determining unit operating capacity based on DC blocking frequency constraints provided by an embodiment of the present invention begins at step 101. In step 101, based on the parameter data of each unit in the system and the load parameter data, equivalent parameter data corresponding to the single-unit model is determined.

[0068] In the present invention, the parameters of each unit and load parameters in the system required for frequency response calculation are obtained, including load damping coefficient D, speed gain R of each unit speed regulator i , inertia time constant H i , unit reheater time constant T Ri , high pressure cylinder power ratio F Hi , unit capacity S i Then, the equivalent calculation of the unit parameters is performed, and the equivalent value becomes a single-machine model to determine the equivalent value R of the unit governor speed gain, the equivalent value H of the inertia time constant, and the equivalent value T of the unit reheater time constant. R , high pressure cylinder power ratio equivalent value F H , unified system benchmark capacity S N .

[0069] In step 102, the startup capacity of the first unit is determined based on the parameter equivalent data and the maximum allowable frequency deviation.

[0070] Preferably, the determining the startup capacity of the first unit based on the parameter equivalent data and the maximum allowable frequency deviation comprises:

[0071] ,

[0072] ,

[0073] ,

[0074]

[0075] ,

[0076] ,

[0077] ,

[0078] ,

[0079] ,

[0080] ,

[0081] Among them, the above formulas are solved simultaneously to determine the startup capacity P of the first unit Gmin1 ; is the maximum allowable frequency deviation; t m is the time when the maximum frequency deviation occurs; is the damping ratio; is the natural oscillation angular frequency; α and is an intermediate variable; is the disturbance power; P L is the load power; T R is the equivalent value of the unit reheater time; F H is the equivalent value of the high-pressure cylinder power ratio; P L is the load power; R is the selected reference value, which is the generator startup capacity P Gmin1 The speed gain per unit value when H is the selected reference value is the generator startup capacity P Gmin1 The inertia time constant per unit value when D is the selected reference value is the load power P L The load damping coefficient per unit value when D * 、H * 、R * and To unify the reference values ​​to the same reference capacity S N The per-unit value below.

[0082] In the present invention, a frequency response function expressed in per-unit value is established to obtain the maximum value expression of the corresponding frequency deviation; then, according to the calculation rules of per-unit value, each parameter is converted to the same reference value, so that the starting capacity P of the first unit to be calculated is expressed in the formula Gmin1 Then, given the maximum transient deviation allowable value and load level and other parameters, the numerical algorithm is used to solve P Gmin1 , get the startup capacity of the first unit.

[0083] Specifically, a simplified second-order system frequency response model is established for the equivalent single-machine system, and the calculation formulas for its natural oscillation angular frequency and damping ratio are:

[0084] ,

[0085] ,

[0086] The expressions of frequency response and maximum frequency deviation are:

[0087] ,

[0088] ,

[0089] ,

[0090] ,

[0091] ,

[0092] ,

[0093] ,

[0094] ,

[0095] Among them, the above formulas are solved simultaneously to determine the startup capacity P of the first unit Gmin1 ; is the maximum allowable frequency deviation; t m is the time when the maximum frequency deviation occurs; is the damping ratio; is the natural oscillation angular frequency; α and is an intermediate variable; is the disturbance power; P L is the load power; T R is the equivalent value of the unit reheater time; F H is the equivalent value of the high-pressure cylinder power ratio; P L is the load power; R is the selected reference value, which is the generator startup capacity P Gmin1 The speed gain per unit value when H is the selected reference value is the generator startup capacity P Gmin1 The inertia time constant per unit value when D is the selected reference value is the load power P L The load damping coefficient per unit value when D * 、H * 、R * and To unify the reference values ​​to the same reference capacity S N The per-unit value below.

[0096] Combining the above formulas, we can establish and P Gmin1 The relationship between , the expression of the maximum frequency deviation becomes:

[0097] ,

[0098] The maximum allowable deviation of the given frequency , use the least squares method to solve the nonlinear equations, and you can calculate PGmin1 .

[0099] In step 103, the startup capacity of the second unit is determined based on the power limit ratio of the primary frequency regulation of the generator and the maximum allowable frequency deviation.

[0100] Preferably, the determining the startup capacity of the second unit based on the generator primary frequency regulation power limit ratio and the maximum allowable frequency deviation includes:

[0101] ,

[0102] Among them, P Gmin2 The startup capacity of the second unit; is the disturbance power; D is the load damping coefficient; The maximum allowable frequency deviation; p is the generator primary frequency regulation power limit ratio.

[0103] In the present invention, considering the power limit constraint of the primary frequency regulation of the generator, at the maximum value of the allowable frequency deviation, the starting capacity P of the second unit is calculated according to the power balance condition. Gmin2 , and the first unit startup capacity P Gmin1 Compare and take the larger value as the final minimum starting capacity P of the unit Gmin .

[0104] Among them, subject to the limitation of the primary frequency regulation capability of conventional units, when the system frequency deviation reaches the transient frequency constraint, assuming that the ratio of the primary frequency regulation limit to the start-up capacity is p, if the generator frequency regulation capability has reached the limit, according to the power balance:

[0105] ,

[0106] The derivation shows that the startup capacity of the second unit under the limit constraint is:

[0107] ,

[0108] Among them, P Gmin2 The startup capacity of the second unit; is the disturbance power; D is the load damping coefficient; is the maximum allowable frequency deviation; p is the power limit ratio of the generator primary frequency regulation.

[0109] In step 104, the minimum startup capacity of the unit is determined based on the maximum value of the first unit startup capacity and the second unit startup capacity.

[0110] In the present invention, in order to meet the frequency constraint, the second unit startup capacity P is taken Gmin2 and the first unit's operating capacity P Gmin1The larger value is taken as the final minimum starting capacity of the unit.

[0111] Preferably, the method further comprises:

[0112] Determining the maximum access capacity of new energy sources based on the minimum startup capacity includes:

[0113] ,

[0114] Among them, P new is the maximum access capacity of new energy; P L is the load power; k is the preset generator output ratio; P Gmin It is the minimum starting capacity of the unit.

[0115] In the present invention, after determining the minimum operating capacity of the unit, the maximum access capacity of renewable energy can be calculated based on the system load level and the ratio of the minimum technical output of the conventional unit to the rated power, which mainly includes:

[0116] Assuming that the ratio of generator output to the minimum operating capacity of the unit is k, the maximum access capacity of new energy can be obtained as:

[0117] ,

[0118] Among them, P new is the maximum access capacity of new energy; P L is the load power; k is the preset generator output ratio; P Gmin It is the minimum starting capacity of the unit.

[0119] In the present invention, the critical ratio of new energy plus DC is defined as the ratio of the maximum access capacity of new energy to the minimum startup capacity. By changing the load damping coefficient, the disturbance power size, and the maximum frequency deviation constraint, the changes in the critical ratio of new energy plus DC are as follows: Figure 2 、 Figure 3 and Figure 4 As shown in the figure, it can be seen that with the increase of the load damping coefficient and the maximum frequency deviation constraint, the maximum renewable energy access capacity that the system can withstand gradually increases; and decreases with the increase of the disturbance power.

[0120] The present invention can be applied to the engineering practice of calculating the minimum startup capacity of conventional units based on the maximum frequency deviation constraint under a DC blocking fault. It can accurately calculate the minimum startup capacity of the unit and the maximum access capacity of new energy, and then limit the maximum access capacity of new energy, thereby improving system stability.

[0121] Figure 5 FIG. 5 is a structural diagram of a system 500 for determining the startup capacity of a generator set based on DC blocking frequency constraints according to an embodiment of the present invention. Figure 5As shown, the unit startup capacity determination system 500 based on DC locking frequency constraint provided in an embodiment of the present invention includes: an equivalent unit 501, a first unit startup capacity determination unit 502, a second unit startup capacity determination unit 503 and a minimum startup capacity determination unit 504.

[0122] Preferably, the equivalent unit 501 is used to perform equivalence based on parameter data of each unit in the system and load parameter data, and determine parameter equivalent data corresponding to the single-machine model.

[0123] Preferably, the first unit startup capacity determination unit 502 is configured to determine the first unit startup capacity based on the parameter equivalent data and the maximum allowable frequency deviation.

[0124] Preferably, the first unit startup capacity determination unit 502 determines the first unit startup capacity based on the parameter equivalent data and the maximum allowable frequency deviation, including:

[0125] ,

[0126] ,

[0127] ,

[0128] ,

[0129] ,

[0130] ,

[0131] ,

[0132] ,

[0133] ,

[0134] ,

[0135] Among them, the above formulas are solved simultaneously to determine the startup capacity P of the first unit Gmin1 ; is the maximum allowable frequency deviation; t m is the time when the maximum frequency deviation occurs; is the damping ratio; is the natural oscillation angular frequency; α and is an intermediate variable; is the disturbance power; P L is the load power; T R is the equivalent value of the unit reheater time; FH is the equivalent value of the high-pressure cylinder power ratio; P L is the load power; R is the selected reference value, which is the generator startup capacity P Gmin1 The speed gain per unit value when H is the selected reference value is the generator startup capacity P Gmin1 The inertia time constant per unit value when D is the selected reference value is the load power P L The load damping coefficient per unit value when D * 、H * 、R * and To unify the reference values ​​to the same reference capacity S N The per-unit value below.

[0136] Preferably, the second unit startup capacity determination unit 503 is configured to determine the second unit startup capacity based on the generator primary frequency regulation power limit ratio and the maximum allowable frequency deviation.

[0137] Preferably, the second unit startup capacity determination unit 503 determines the second unit startup capacity based on the generator primary frequency regulation power limit ratio and the maximum allowable frequency deviation, including:

[0138] ,

[0139] Among them, P Gmin2 The startup capacity of the second unit; is the disturbance power; D is the load damping coefficient; is the maximum allowable frequency deviation; p is the power limit ratio of the generator primary frequency regulation.

[0140] Preferably, the minimum startup capacity determining unit 504 is configured to determine the minimum startup capacity of the unit based on the maximum value of the first unit startup capacity and the second unit startup capacity.

[0141] Preferably, the system further comprises:

[0142] A maximum access capacity determination unit is configured to determine the maximum access capacity of the new energy source based on the minimum startup capacity, including:

[0143] ,

[0144] Among them, P new is the maximum access capacity of new energy; P L is the load power; k is the preset generator output ratio; P Gmin It is the minimum starting capacity of the unit.

[0145] The system 500 for determining the unit startup capacity based on DC blocking frequency constraints in an embodiment of the present invention corresponds to the method 100 for determining the unit startup capacity based on DC blocking frequency constraints in another embodiment of the present invention, and will not be described in detail here.

[0146] According to another aspect of the present invention, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any step of a method for determining the startup capacity of a unit based on DC blocking frequency constraints.

[0147] According to another aspect of the present invention, the present invention provides an electronic device, including:

[0148] The computer-readable storage medium described above; and

[0149] One or more processors are configured to execute the program in the computer-readable storage medium.

[0150] The invention has been described above with reference to a few embodiments. However, it is readily apparent to a person skilled in the art that other embodiments than the ones disclosed above are equally within the scope of the invention, as defined by the appended patent claims.

[0151] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a / the [means, component, etc.]" are to be interpreted openly as referring to at least one instance of the means, component, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not necessarily need to be performed in the exact order disclosed, unless explicitly stated otherwise.

[0152] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0153] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, 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 produce 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 flowcharts and / or block diagrams. 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.

[0154] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work 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 The function specified in one or more boxes.

[0155] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0156] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A method for determining the startup capacity of a unit based on DC blocking frequency constraints, characterized in that: The method comprises: Based on the parameter data and load parameter data of each unit in the system, the parameter equivalent data corresponding to the single unit model is determined; Determining the startup capacity of the first unit based on the parameter equivalent data and the maximum allowable frequency deviation; Determining the startup capacity of the second unit based on the generator primary frequency regulation power limit ratio and the maximum allowable frequency deviation; Determining a minimum operating capacity of the unit based on a maximum value of the operating capacity of the first unit and the operating capacity of the second unit; The determining of the startup capacity of the first unit based on the parameter equivalent data and the maximum allowable frequency deviation includes: Among them, the above formulas are solved simultaneously to determine the startup capacity P of the first unit Gmin1 ;Δf m* is the maximum allowable frequency deviation; t m is the time when the maximum frequency deviation occurs; ζ is the damping ratio; ω n is the natural oscillation angular frequency; α and ω r is the intermediate variable; ΔP is the disturbance power; T R is the equivalent value of the unit reheater time; F H is the equivalent value of the high-pressure cylinder power ratio; P L is the load power; R is the selected reference value, which is the generator startup capacity P Gmin1 The speed gain per unit value when H is the selected reference value is the generator startup capacity P Gmin1 The inertia time constant per unit value when D is the selected reference value is the load power P L The load damping coefficient per unit value when D * 、H * 、R * and ΔP * To unify the reference values ​​to the same reference capacity S N per-unit value under ; The determining of the startup capacity of the second unit based on the primary frequency regulation power limit ratio of the generator and the maximum allowable frequency deviation includes: Among them, P Gmin2 is the start-up capacity of the second unit; ΔP is the disturbance power; D is the selected reference value for the load power P L per unit load damping coefficient when Δf m* is the maximum allowable frequency deviation; p is the power limit ratio of the generator primary frequency regulation.

2. The method according to claim 1, characterized in that The method further comprises: Determining the maximum access capacity of new energy sources based on the minimum startup capacity includes: P new =P L -kP Gmin , Among them, P new is the maximum access capacity of new energy; P L is the load power; k is the preset generator output ratio; P Gmin It is the minimum starting capacity of the unit.

3. A system for determining the startup capacity of a unit based on DC blocking frequency constraints, characterized in that: The system comprises: The equivalent unit is used to determine the parameter equivalent data corresponding to the single-machine model based on the parameter data and load parameter data of each unit in the system; A first unit startup capacity determination unit, configured to determine the first unit startup capacity based on the parameter equivalent data and a maximum frequency allowable deviation; A second unit startup capacity determination unit, configured to determine the second unit startup capacity based on the generator primary frequency regulation power limit ratio and the maximum allowable frequency deviation; a minimum startup capacity determining unit, configured to determine a minimum startup capacity of a unit based on a maximum value of the startup capacity of the first unit and the startup capacity of the second unit; The first unit startup capacity determination unit determines the first unit startup capacity based on the parameter equivalent data and the maximum allowable frequency deviation, including: Among them, the above formulas are solved simultaneously to determine the startup capacity P of the first unit Gmin1 ;Δf m* is the maximum allowable frequency deviation; t m is the time when the maximum frequency deviation occurs; ζ is the damping ratio; ω n is the natural oscillation angular frequency; α and ω r is the intermediate variable; ΔP is the disturbance power; T R is the equivalent value of the unit reheater time; F H is the equivalent value of the high-pressure cylinder power ratio; P L is the load power; R is the selected reference value, which is the generator startup capacity P Gmin1 The speed gain per unit value when H is the selected reference value is the generator startup capacity P Gmin1 The inertia time constant per unit value when D is the selected reference value is the load power P L The load damping coefficient per unit value when D * 、H * 、R * and ΔP * To unify the reference values ​​to the same reference capacity S N per-unit value under ; The second unit startup capacity determination unit determines the second unit startup capacity based on the generator primary frequency regulation power limit ratio and the maximum allowable frequency deviation, including: Among them, P Gmin2 is the start-up capacity of the second unit; ΔP is the disturbance power; D is the selected reference value for the load power P L per unit load damping coefficient when Δf m* is the maximum allowable frequency deviation; p is the power limit ratio of the generator primary frequency regulation.

4. The system according to claim 3, characterized in that The system further comprises: A maximum access capacity determination unit is configured to determine the maximum access capacity of the new energy source based on the minimum startup capacity, including: P new =P L -kP Gmin , Among them, P new is the maximum access capacity of new energy; P L is the load power; k is the preset generator output ratio; P Gmin It is the minimum starting capacity of the unit.

5. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 1 to 2 are implemented.

6. An electronic device, characterized in that: include: The computer-readable storage medium of claim 5; as well as One or more processors are configured to execute the program in the computer-readable storage medium.

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