Frequency boundary determination method and apparatus, and computer device

Abstract

The application relates to the technical field of power systems, in particular to a frequency boundary determination method and device and computer equipment. The method comprises the following steps: acquiring an active power shortage of a preset disturbance event; determining disturbed distribution power of each substation according to the active power shortage and a disturbance power distribution coefficient of each substation; for any substation, the disturbed distribution power of the substation is sent to the substation, so that the substation determines a lower limit value of the frequency of the substation according to the corresponding disturbed distribution power. The method can reduce the amount of collected parameters and calculation, and greatly improves the frequency calculation speed.

Description

Technical Field

[0001] This application relates to the field of power system technology, and in particular to a method, apparatus and computer equipment for determining frequency boundaries. Background Technology

[0002] With the accelerated construction of ultra-high voltage direct current (UHVDC) lines, local power systems are experiencing a high proportion of DC power feed-in. When a DC line fails, the system's active power deficit is severe, and the local power source's frequency support capacity is insufficient, making it highly susceptible to frequency instability. Power system transient frequency boundary prediction technology has become an important tool to ensure system safety.

[0003] Traditional frequency boundary prediction techniques often employ a centralized, network-wide modeling approach. The power grid operation center needs to construct a dynamic model of the entire system, collecting all frequency-related parameters such as inertia, damping, and primary frequency regulation of all generating units, and dynamically adjusting these parameters based on real-time system operation. After obtaining the dynamic model of the entire system (i.e., the full-order model), numerical calculation methods are used to perform simulations under different anticipated accidents to obtain the system's lowest frequency point. This method requires a high degree of knowledge of the parameters of each generating unit, significantly increasing the workload of data acquisition and updating for the operation department.

[0004] It is evident that current frequency boundary prediction methods suffer from the problems of large amounts of collected parameters and computational load, resulting in slow frequency analysis and calculation speeds across the entire network. Summary of the Invention

[0005] Therefore, it is necessary to provide a frequency boundary determination method, apparatus, computer equipment, computer-readable storage medium, and computer program product to address the above-mentioned technical problems, so as to achieve rapid calculation of the lower frequency limit of each node in the power grid without requiring information of each node.

[0006] Firstly, this application provides a frequency boundary determination method applied to a main station, the method comprising:

[0007] Obtain the active power deficit for preset disturbance events;

[0008] Based on the active power deficit and the disturbance power allocation coefficient of each substation, the disturbed allocation power of each substation is determined.

[0009] For any of the substations, the disturbed allocation power of the substation is sent to the substation so that the substation determines the frequency lower limit value of the substation based on the corresponding disturbed allocation power.

[0010] In one embodiment, obtaining the active power deficit of a preset disturbance event includes:

[0011] The system acquires multiple power generation capacities and the DC feed-in power of each UHVDC line, wherein the multiple power generation capacities include the power generation capacities corresponding to each of the substations.

[0012] The maximum value among the plurality of power generation powers is taken as the target power generation power;

[0013] The maximum value between the DC feed-in power of each UHVDC line and the target power generation is taken as the active power deficit for the preset disturbance event.

[0014] In one embodiment, the frequency boundary determination method further includes:

[0015] For any of the substations, the voltage amplitude of the substation, the impedance value between the substation and the disturbing substation, and the voltage phase difference between the substation and the disturbing substation are obtained, wherein the disturbing substation is the substation that has experienced the preset disturbance event;

[0016] For any of the substations, the disturbance power distribution coefficient of the substation is obtained based on the voltage amplitude of the substation, the voltage amplitude of the disturbing substation, the impedance value between the substation and the disturbing substation, and the voltage phase difference between the substation and the disturbing substation.

[0017] Secondly, this application also provides a frequency boundary determination method applied to a substation, the method comprising:

[0018] The system receives the disturbed power allocation sent by the master station, wherein the disturbed power allocation is the power determined by the master station based on the active power deficit of the preset disturbance event and the disturbance power allocation coefficient of each substation.

[0019] The lower frequency limit of the substation is determined based on the disturbed allocated power.

[0020] In one embodiment, determining the frequency lower limit of the substation based on the disturbed allocated power includes:

[0021] Based on the inertial time constant, damping coefficient, governor time constant, and unit regulation power of the substation, determine the frequency boundary parameters of the substation;

[0022] The first frequency drop value of the substation is determined based on the frequency boundary parameters of the substation and the disturbed allocated power of the substation.

[0023] The lower frequency limit of the substation is obtained based on the frequency under steady-state conditions and the first frequency drop value of the substation.

[0024] In one embodiment, determining the frequency boundary parameters of the substation based on its inertial time constant, damping coefficient, governor time constant, and unit regulation power includes:

[0025] Based on the inertial time constant, damping coefficient, governor time constant, and unit regulation power of the substation, multiple sub-parameters of the substation are determined.

[0026] The frequency boundary parameters of the substation are determined based on the input-output stability BIBO theory and the multiple sub-parameters.

[0027] In one embodiment, the determination of multiple sub-parameters of the substation based on its inertial time constant, damping coefficient, governor time constant, and unit regulation power includes:

[0028] Based on the inertial time constant, damping coefficient, governor time constant, unit regulation power of the substation, as well as the frequency drop value of the substation and the change in prime mover input power of the substation, construct the nominal system model of the substation;

[0029] Obtain the Lyapunov function of the nominal system model;

[0030] Based on the Lyapunov function, the frequency drop value of the substation, and the change in the prime mover input power of the substation, multiple sub-parameters of the substation are determined.

[0031] Thirdly, this application also provides a frequency boundary determination device, applied to a main station, the device comprising:

[0032] The disturbance acquisition module is used to acquire the active power deficit of a preset disturbance event;

[0033] The power calculation module is used to determine the disturbed power allocation of each substation based on the active power deficit and the disturbance power allocation coefficient of each substation.

[0034] The power allocation module is used to send the disturbed allocated power of any of the substations to the substation, so that the substation can determine the frequency lower limit value of the substation according to the corresponding disturbed allocated power.

[0035] In one embodiment, the disturbance acquisition module is further configured to acquire multiple power generation capacities and acquire the DC feed-in power of each UHVDC line, wherein the multiple power generation capacities include the power generation capacities corresponding to each of the substations; the maximum value among the multiple power generation capacities is used as the target power generation capacities; and the maximum value between the DC feed-in power of each UHVDC line and the target power generation capacities is used as the active power deficit power of the preset disturbance event.

[0036] In one embodiment, the frequency boundary determination device further includes a coefficient determination module, which is used to obtain, for any one of the substations, the voltage amplitude of the substation, the impedance value between the substation and the disturbing substation, and the voltage phase difference between the substation and the disturbing substation, wherein the disturbing substation is the substation that has experienced the preset disturbance event; and for any one of the substations, to obtain the disturbance power allocation coefficient of the substation based on the voltage amplitude of the substation, the voltage amplitude of the disturbing substation, the impedance value between the substation and the disturbing substation, and the voltage phase difference between the substation and the disturbing substation.

[0037] Fourthly, this application also provides a frequency boundary determination device applied to a substation, the device comprising:

[0038] The power receiving module is used to receive the disturbed allocated power sent by the master station. The disturbed allocated power is the power determined by the master station based on the active power deficit of the preset disturbance event and the disturbance power allocation coefficient of each sub-station.

[0039] The frequency calculation module is used to determine the lower frequency limit of the substation based on the disturbed allocated power.

[0040] In one embodiment, the frequency calculation module is further configured to determine the frequency boundary parameters of the substation based on the substation's inertial time constant, damping coefficient, governor time constant, and unit regulation power; determine the first frequency drop value of the substation based on the frequency boundary parameters of the substation and the disturbed allocated power of the substation; and obtain the lower frequency limit value of the substation based on the frequency under steady-state conditions and the first frequency drop value of the substation.

[0041] In one embodiment, the frequency calculation module is further configured to determine multiple sub-parameters of the substation based on the substation's inertial time constant, damping coefficient, governor time constant, and unit regulation power; and to determine the frequency boundary parameters of the substation based on the input-output stability BIBO theory and the multiple sub-parameters.

[0042] In one embodiment, the frequency calculation module is further configured to construct a nominal system model of the substation based on the substation's inertial time constant, damping coefficient, governor time constant, unit regulation power, frequency drop value of the substation, and change in prime mover input power of the substation; obtain the Lyapunov function of the nominal system model; and determine multiple sub-parameters of the substation based on the Lyapunov function, the frequency drop value of the substation, and the change in prime mover input power of the substation.

[0043] Fifthly, this application also provides a frequency boundary determination system, the system comprising: a master station and multiple substations, wherein the master station is used to acquire the active power deficit of a preset disturbance event, determine the disturbed allocated power of each substation based on the active power deficit and the disturbance power allocation coefficient of each substation, and send the disturbed allocated power of each substation to each substation; the substations are used to receive the disturbed allocated power sent by the master station, and determine the frequency lower limit value of the substation based on the disturbed allocated power.

[0044] Sixthly, this application also provides a computer device, the computer device including a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps in the above-described method embodiments.

[0045] In a seventh aspect, this application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in the above-described method embodiments.

[0046] Eighthly, this application also provides a computer program product, which includes a computer program that, when executed by a processor, implements the steps in the above-described method embodiments.

[0047] The aforementioned frequency boundary determination method, apparatus, computer equipment, computer-readable storage medium, and computer program product acquire the active power deficit of a preset disturbance event; determine the disturbed allocated power of each substation based on the active power deficit and the disturbance power allocation coefficient of each substation; and for any substation, send the disturbed allocated power of the substation to the substation so that the substation determines the frequency lower limit value of the substation based on the corresponding disturbed allocated power. Compared to traditional technologies where the power grid operation center constructs a dynamic model of the entire system and collects frequency-related parameters such as inertia, damping, and primary frequency regulation of all units in the system in real time for calculation, the frequency boundary determination method, device, computer equipment, computer-readable storage medium, and computer program product provided in this application construct an information interaction mode between the master station and the substations. After the master station obtains the active power deficit of the preset disturbance event, it sends the disturbance allocation power determined by the active power deficit and the disturbance power allocation coefficient of each substation to each substation. This allows each substation to determine its frequency lower limit value based on the corresponding disturbance allocation power. This eliminates the need for the master station to obtain detailed parameters of all units in the entire network in real time, reducing its dependence on information from each unit. In other words, it reduces the amount of parameters collected and the amount of calculation, greatly improving the frequency calculation speed. Attached Figure Description

[0048] Figure 1This is a flowchart illustrating a frequency boundary determination method in one embodiment.

[0049] Figure 2 This is a flowchart illustrating step 102 in one embodiment.

[0050] Figure 3 This is a flowchart illustrating a frequency boundary determination method in one embodiment.

[0051] Figure 4 This is a flowchart illustrating a frequency boundary determination method in one embodiment.

[0052] Figure 5 This is a flowchart illustrating step 404 in one embodiment.

[0053] Figure 6 This is a flowchart illustrating step 502 in one embodiment.

[0054] Figure 7 This is a flowchart illustrating step 602 in one embodiment.

[0055] Figure 8 This is a schematic diagram of a frequency boundary determination system in one embodiment.

[0056] Figure 9 This is a flowchart illustrating a frequency boundary determination method in one embodiment.

[0057] Figure 10 This is a structural block diagram of a frequency boundary determination device in one embodiment.

[0058] Figure 11 This is a structural block diagram of a frequency boundary determination device in one embodiment.

[0059] Figure 12 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0060] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0061] Currently, with the accelerated construction of ultra-high voltage direct current (UHVDC) lines, local power systems are experiencing a high proportion of DC power input. When DC lines fail, the system suffers severe active power deficits, and local power sources lack sufficient frequency support, making them highly susceptible to frequency instability. Against this backdrop, power system transient frequency boundary prediction technology has become a crucial tool for ensuring system safety. Traditional frequency boundary prediction techniques often employ a centralized, network-wide modeling approach. The power grid operation center needs to construct a dynamic model of the entire system, collecting all frequency-related parameters such as inertia, damping, and primary frequency regulation of all generating units, and dynamically adjusting them based on real-time system operation. After obtaining the full-order system model, numerical calculation methods are used to perform simulations under different anticipated accidents to obtain the system's lowest frequency point. This approach requires a high degree of knowledge of the parameters of each generating unit, significantly increasing the workload of data collection and updating for the operation department.

[0062] In summary, most power system frequency process analysis work focuses on frequency process modeling. Most methods employ frequency domain modeling of the system's active power and frequency, and time domain differential equation modeling. These methods require the grid dispatch center and other analysts to have a complete grasp of the entire network's operational status. The models, structures, connections, and detailed parameters of each component in the system are essential information for their application. In actual operation, due to the large number of nodes in the system, the parameters of a massive number of generating units are difficult to fully grasp in real time within the grid dispatch department. Modeling deviations in the frequency process can lead to the failure of these analysis methods. Furthermore, these methods primarily use the single-machine equivalent approach for system frequency analysis, which fails to reflect the dynamic frequency differences between nodes and cannot meet the node frequency analysis needs of large power grids with low node information dependence.

[0063] Based on this, the embodiments of this application provide a frequency boundary determination method to achieve rapid calculation of the lower frequency limit of each substation in the power grid without requiring information of each substation.

[0064] In one embodiment, such as Figure 1 As shown, a frequency boundary determination method is provided. This embodiment illustrates the method by applying it to a server. It is understood that this method can also be applied to a terminal, or to a system including both a terminal and a server, and is implemented through interaction between the terminal and the server. In this embodiment, the frequency boundary determination method is applied to a main station, and the method includes the following steps:

[0065] Step 102: Obtain the active power deficit of the preset disturbance event.

[0066] In this embodiment, the preset disturbance event can be a preset typical active power disturbance event in the power grid. The active power deficit is the amount of active power reduction in the entire power grid after the preset disturbance event occurs.

[0067] Step 104: Determine the disturbed power allocation for each substation based on the active power deficit and the disturbance power allocation coefficient of each substation.

[0068] In this embodiment, substations can be deployed at each generator unit in the entire network, one substation can be deployed at one generator unit, and one substation can be connected to one node in the entire network. The disturbance power allocation coefficient of each substation can be obtained based on the parameters of each substation. The disturbance-assigned power of each substation is the value of the decrease in active power of each substation under a preset disturbance event.

[0069] For example, the disturbed power allocation of each substation satisfies the following formula (I).

[0070]

[0071] Where n is the number of substations in the power grid system, substation j is the substation where the preset disturbance event occurs, and substation i is any substation other than the substation where the preset disturbance event occurs. ΔP i Assign power to the disturbed substation i, K ij K is the disturbance power allocation factor for substation i. mj Let m be the disturbance power allocation coefficient for substation m, where m is an integer from 1 to n. This is the sum of the disturbance power allocation coefficients for each substation. ΔP sum This represents the active power deficit for a pre-set disturbance event. ΔP sum It can be a power sequence that varies with time, ΔP i It can also be a power sequence that varies over time.

[0072] Step 106: For any substation, send the disturbed allocation power of the substation to the substation so that the substation can determine the frequency lower limit value of the substation according to the corresponding disturbed allocation power.

[0073] In this embodiment, after the master station determines the disturbed allocated power of the substation, it can send each disturbed allocated power to the corresponding substation, so that each substation can calculate the lower frequency limit based on the corresponding disturbed allocated power and report the obtained lower frequency limit to the master station. The lower frequency limit of the substation is the frequency at which the frequency drop caused by the disturbance reaches its maximum under the condition of a preset disturbance event, i.e., the frequency boundary.

[0074] The aforementioned frequency boundary determination method obtains the active power deficit of a preset disturbance event; determines the disturbed allocated power of each substation based on the active power deficit and the disturbance power allocation coefficient of each substation; and for any substation, sends the disturbed allocated power of the substation to the substation so that the substation can determine its frequency lower limit based on the corresponding disturbed allocated power. Compared to traditional technologies where the power grid operation center constructs a dynamic model of the entire system and collects frequency-related parameters such as inertia, damping, and primary frequency regulation of all units in the system in real time for calculation, the frequency boundary determination method provided in this application establishes an information interaction mode between the master station and substations. After obtaining the active power deficit of the preset disturbance event, the master station sends the disturbed allocated power determined by the active power deficit and the disturbance power allocation coefficient of each substation to each substation so that each substation can determine its frequency lower limit based on the corresponding disturbed allocated power. This eliminates the need for the master station to obtain detailed parameters of all units in the entire network in real time, reducing the dependence on information from each unit, thus reducing the amount of parameters collected and the amount of calculation, and greatly improving the frequency calculation speed.

[0075] In one embodiment, such as Figure 2 As shown, in step 102, obtaining the active power deficit of the preset disturbance event may include:

[0076] Step 202: Obtain multiple power generation capacities and the DC feed-in power of each UHVDC line. The multiple power generation capacities include the power generation capacities corresponding to each substation.

[0077] For example, there may be four ultra-high voltage direct current (UHVDC) lines in the power grid, meaning there are four substations that can experience disturbances related to the UHVDC lines. Each substation in the power grid system has a different power generation capacity.

[0078] Step 204: Take the maximum value among the multiple power generation outputs as the target power generation output.

[0079] Each substation in a power grid system has a different generating capacity, and the highest generating capacity can be used as the target generating capacity. For example, the substation deployed with the largest capacity unit generally has the highest generating capacity, so the generating capacity of the substation deployed with the largest capacity unit can be used as the target generating capacity.

[0080] Step 206: The maximum value between the DC feed-in power of each UHVDC line and the target power generation is taken as the active power deficit for the preset disturbance event.

[0081] The main station can obtain the maximum real-time feed-in power of a single UHVDC line and the real-time active power of the largest capacity unit in the system. The maximum value of the two is taken to form a typical active power disturbance event as a preset disturbance event, and the active power deficit of the preset disturbance event and the substation where the preset disturbance event occurs are determined.

[0082] The active power deficit of the preset disturbance event can satisfy the following formula (II).

[0083] ΔP sum =max(P HVDC ,P maxc Formula (II)

[0084] Among them, P HVDC P represents the DC feed-in power of the ultra-high voltage direct current (UHVDC) line. max c The target power generation capacity is the maximum power generation capacity of a single unit within the system. For example, if P... max c To maximize P, max c The active power deficit ΔP as a preset disturbance event sum That is, P max c The corresponding substation is the substation where the preset disturbance event occurs.

[0085] In this embodiment of the disclosure, the maximum real-time feed-in power of a single UHVDC line and the real-time active power of the largest capacity unit in the system are obtained, and the maximum value of the two is taken to form a preset disturbance event, so that the preset disturbance event can cause the most severe power deficit, thereby realizing the calculation of the lower limit of frequency and ensuring the safety of the power grid system.

[0086] In one embodiment, such as Figure 3 As shown, the frequency boundary determination method may also include:

[0087] Step 302: For any substation, obtain the voltage amplitude of the substation, the impedance value between the substation and the disturbing substation, and the voltage phase difference between the substation and the disturbing substation. The disturbing substation is the substation that has experienced a preset disturbance event.

[0088] The master station can monitor the overall network operation status and line parameters through a PMU (Power System Synchronization Phasor Measurement Unit) and communication system. The overall network operation status includes the voltage amplitude and phase of each substation within the grid, and the line parameters include the impedance of each line. Real-time grid topology maps can be obtained, and impedance data for each grid line can be generated by combining this data with a historical parameter database. The real-time grid topology map reflects the connection relationships between substations, and the lines are the transmission lines connecting various generating units; that is, the impedance of the lines represents the impedance values ​​between each substation.

[0089] Step 304: For any substation, obtain the disturbance power distribution coefficient of the substation based on the voltage amplitude of the substation, the voltage amplitude of the disturbing substation, the impedance value between the substation and the disturbing substation, and the voltage phase difference between the substation and the disturbing substation.

[0090] The disturbance power allocation coefficient of the substation is positively correlated with the voltage amplitude of the substation and the voltage amplitude of the disturbing substation, and positively correlated with the cosine of the voltage phase difference between the substation and the disturbing substation. The disturbance power allocation coefficient of the substation is negatively correlated with the impedance value between the substation and the disturbing substation. For example, the disturbance power allocation coefficient can satisfy the following formula (III).

[0091]

[0092] Among them, U i U represents the voltage amplitude of substation i. j X is the voltage amplitude of the disturbance substation j. ij Let δ be the impedance value between substation i and the disturbing substation j. ij Let be the phase difference between substation i and the disturbed substation j.

[0093] In this embodiment, based on the voltage amplitude, impedance value, and voltage phase difference of each substation obtained by the master station, the disturbance power allocation coefficient of each substation is obtained. This allows the master station to determine the disturbance allocation power of each substation according to the disturbance power allocation coefficient, and then the substation to determine the frequency lower limit value of the substation according to the corresponding disturbance allocation power. This avoids the master station collecting frequency-related parameters such as inertia, damping, and primary frequency modulation of all units in the system in real time, reducing the amount of parameters collected and the amount of calculation, and greatly improving the frequency calculation speed.

[0094] In one embodiment, such as Figure 4 As shown, a frequency boundary determination method is provided, applied to a substation. The method includes the following steps:

[0095] Step 402: Receive the disturbed power allocation sent by the master station. The disturbed power allocation is the power determined by the master station based on the active power deficit of the preset disturbance event and the disturbance power allocation coefficient of each substation.

[0096] In this process, after the master station determines the corresponding disturbed allocation power of each substation through the disturbance power allocation coefficient of each substation, each substation can receive the corresponding disturbed allocation power sent by the master station.

[0097] Step 404: Determine the lower frequency limit of the substation based on the power allocated to the disturbance.

[0098] Once any substation receives the corresponding disturbed power allocation, it can calculate the frequency boundary parameters based on the substation's inertial time constant, damping coefficient, speed controller time constant, and unit adjustment power, and determine the substation's lower frequency limit value based on the frequency boundary parameters and the corresponding disturbed power allocation.

[0099] In this embodiment, each substation determines its lower frequency limit based on the disturbed power distribution sent by the master station. This avoids the need for the master station to collect frequency-related parameters such as inertia, damping, and primary frequency modulation of all units in the system in real time, thus reducing the amount of parameters collected and the computational load, and greatly improving the frequency calculation speed.

[0100] In one embodiment, such as Figure 5 As shown, in step 404, determining the lower frequency limit of the substation based on the disturbed allocated power may include:

[0101] Step 502: Determine the frequency boundary parameters of the substation based on its inertial time constant, damping coefficient, governor time constant, and unit regulation power.

[0102] The frequency boundary parameters can include a first frequency boundary parameter and a second frequency boundary parameter. Multiple sub-parameters of the substation can be determined based on its inertial time constant, damping coefficient, governor time constant, and unit regulating power. The first and second frequency boundary parameters can then be calculated based on these sub-parameters.

[0103] Step 504: Determine the first frequency drop value of the substation based on the frequency boundary parameters of the substation and the disturbed allocated power of the substation.

[0104] In this embodiment, the first frequency drop value of the substation is the frequency value that the substation drops under the action of a preset disturbance event. The first frequency drop value of the substation is positively correlated with the substation's frequency boundary parameters and the disturbed allocated power. For example, the first frequency drop value of the substation can satisfy the following formula (iv).

[0105] Δf1=γ‖ΔP i || ∞ +β Formula (IV)

[0106] Where Δf1 is the first frequency drop value, γ and β are the first frequency boundary parameters and the second frequency boundary parameters, and ||ΔP|| i || ∞ ΔP for substation i i The infinite norm, at this time, ΔP i Given a time-varying sequence of disturbed power allocation. The ΔP of substation i. i The infinite norm is ΔP. i The maximum value of ΔP can be obtained based on the active power deficit of substation i at the time of the disturbance. i The maximum value. For example, ||ΔP|| i || ∞ The following formula (V) can be satisfied.

[0107] ||ΔP i ||∞ =sup[ΔP i [(t)]=ΔP i (0 + Formula (5)

[0108] Wherein, sup[ΔP i [(t)] represents the maximum value of the disturbed power allocation sequence of substation i, ΔP i (0 + ) represents the active power deficit of substation i when the disturbance occurs.

[0109] Step 506: Based on the frequency under steady-state conditions and the first frequency drop value of the substation, obtain the lower frequency limit of the substation.

[0110] In this embodiment of the application, the difference between the frequency under steady-state operating conditions and the first frequency drop value of the substation can be used as the lower frequency limit of the substation. For example, the lower frequency limit of the substation can satisfy the following formula (vi).

[0111] f min =f0-Δf1 Formula (VI)

[0112] For any substation, f min Δf1 is the lower limit of the substation's frequency, f0 is the frequency under steady-state conditions, f0 is generally 50Hz, and Δf1 is the first frequency drop value.

[0113] In this embodiment of the disclosure, a first frequency drop value of the substation is determined based on the frequency boundary parameters of the substation, and then a lower frequency limit value of the substation is determined based on the first frequency drop value, thereby ensuring the safety of the power grid system.

[0114] In one embodiment, such as Figure 6 As shown, in step 502, based on the substation's inertial time constant, damping coefficient, governor time constant, and unit regulation power, the frequency boundary parameters of the substation are determined, which may include:

[0115] Step 602: Based on the substation's inertial time constant, damping coefficient, governor time constant, and unit regulation power, determine and acquire multiple sub-parameters of the substation.

[0116] The substation's multiple sub-parameters can include a first sub-parameter c1, a second sub-parameter c2, a third sub-parameter c3, a fourth sub-parameter c4, a fifth sub-parameter η1, a sixth sub-parameter η2, and a seventh sub-parameter L. These sub-parameters can be obtained based on a coefficient matrix composed of the substation's inertial time constant, damping coefficient, governor time constant, and unit regulating power.

[0117] Step 604: Using the BIBO theory of input-output stability, determine the frequency boundary parameters of the substation based on multiple sub-parameters.

[0118] In this embodiment, the multiple sub-parameters of the substation may include a first sub-parameter c1, a second sub-parameter c2, a third sub-parameter c3, a fourth sub-parameter c4, a fifth sub-parameter η1, a sixth sub-parameter η2, and a seventh sub-parameter L. The frequency boundary parameters of the substation may include a first frequency boundary parameter γ and a second frequency boundary parameter β. The first frequency boundary parameter γ may be positively correlated with the second sub-parameter c2, the fourth sub-parameter c4, the fifth sub-parameter η1, the sixth sub-parameter η2, and the seventh sub-parameter L, and negatively correlated with the first sub-parameter c1 and the third sub-parameter c3. The second frequency boundary parameter β may be positively correlated with the second sub-parameter c2 and the fifth sub-parameter η1, and negatively correlated with the first sub-parameter c1.

[0119] For example, according to the input-output stability BIBO (Bounded Input Bounded Output) theory, the first frequency boundary parameter γ and the second frequency boundary parameter β of the substation satisfy the following formula (VII).

[0120]

[0121] Where, ‖x0‖ is the initial norm of the state variables of the state space model of the substation, which can satisfy the following formula (VIII).

[0122] ||x0|| = max(|Δf(t0)|,|ΔP m (t0)|) Formula (VIII)

[0123] Where t0 is the time when the preset disturbance event occurs, Δf(t0) is the change in terminal frequency of the substation at time t0, and ΔP m (t0) represents the change in prime mover input power at time t0 of this substation. When t0 is the time when the preset disturbance event occurs, Δf(t0) and ΔP... m (t0) are all 0. The state-space model of the substation is a linear system, and according to the BIBO theorem, the seventh sub-parameter L = 1.

[0124] In this embodiment of the disclosure, a first frequency boundary parameter and a second frequency boundary parameter of a substation are determined based on multiple sub-parameters, so that each substation can determine its lower frequency limit value according to the corresponding first frequency boundary parameter, second frequency boundary parameter and disturbed power allocation.

[0125] In one embodiment, such as Figure 7As shown, in step 602, based on the substation's inertial time constant, damping coefficient, governor time constant, and unit regulation power, several sub-parameters of the substation are determined, which may include:

[0126] Step 702: Based on the substation's inertial time constant, damping coefficient, governor time constant, unit regulation power, frequency drop value of the substation, and change in prime mover input power of the substation, construct the nominal system model of the substation.

[0127] The per-unit form of the active-frequency dynamic model of the substation can be constructed based on the substation's inertial time constant, damping coefficient, governor time constant, unit regulating power, frequency drop value, prime mover input power change, and first disturbance distribution power. The per-unit form of the active-frequency dynamic model of the substation satisfies the following formula (IX).

[0128]

[0129] Where H is the inertial time constant of the substation, D is the damping coefficient of the substation, and T is the inertial time constant. st Here, ΔP represents the governor time constant, and K represents the unit regulating power. These parameters are inherent to the unit within the substation and can be directly obtained from the substation. m ΔP represents the change in the prime mover input power of the substation, Δf represents the frequency drop of the substation, and ΔP represents the frequency drop of the substation. i1 Allocate power to the first affected substation.

[0130] The per-unit form of the active-frequency dynamic model of the substation is rewritten as a state-space model, which satisfies the following formula (x).

[0131]

[0132] The input term of the first disturbed power allocation in the state-space model is removed to obtain the nominal system model of the substation. The nominal system model of the substation satisfies formula (XI).

[0133]

[0134] The aforementioned nominal system model is a time-invariant linear system. This is the coefficient matrix of the nominal system model.

[0135] Step 704: Obtain the Lyapunov function of the nominal system model.

[0136] For example, the Lyapunov function of the nominal system model satisfies the following formula (XII).

[0137] V(Δf,ΔP m )=[Δf,ΔPm ]P[Δf,ΔP m ] T Formula (12)

[0138] Where V(Δf,ΔP) m Let ) be the Lyapunov function of the nominal system model, and P be a symmetric positive definite real matrix. P can be obtained by the following formula (xiii).

[0139]

[0140] Among them, due to the actual operation of the unit's power angle (i.e., Δf) and mechanical power (i.e., ΔP) m All are stable, meaning the coefficient matrix of the nominal system model is a Hurwitz matrix. ( According to the stability theory of linear systems, in formula (xiii), Q is any positive definite symmetric matrix, and its positive definite symmetric solution P is unique. That is, Q is taken as the identity matrix.

[0141] Substituting Q into formula (xiii), we find that P satisfies the following formula (xiv).

[0142]

[0143] Step 706: Determine multiple sub-parameters of the substation based on the Lyapunov function, the frequency drop value of the substation, and the change in the prime mover input power of the substation.

[0144] The Lyapunov function V(Δf,ΔP) can be used. m Differentiation yields the following formula (XV).

[0145]

[0146] The first sub-parameter c1, the second sub-parameter c2, the third sub-parameter c3, and the fourth sub-parameter c4 are related terms to the Lyapunov function of the nominal system model, and they satisfy the following formulas (xvii), (xvii), (xviii) and (xixteen).

[0147]

[0148]

[0149]

[0150]

[0151] Where inf[] represents the lower bound, taking the minimum value, and sup[] represents the upper bound, taking the maximum value. The domain D is (-1,0)∪(0,1). Δf, ΔP m Let c1 be any value taken in the domain D. The first sub-parameter c1, the second sub-parameter c2, the third sub-parameter c3, and the fourth sub-parameter c4 are independent of the disturbed power allocation of the substation.

[0152] The fifth sub-parameter η1 and the sixth sub-parameter η2 satisfy the following formulas (XIX) and (XX).

[0153]

[0154]

[0155] Where Δf represents the first disturbance allocation power ΔP of substation i at different times. i1 The frequency deviation is defined as follows. The domain A is (0,1). The substation can perform ΔP on the unit. i1 For perturbation tests within the range (0,1), Δf in formulas (xIX) and (XX) can be calculated using formula (X), where Δf∈(0,1), ΔP m For any value taken in the domain A, the maximum values ​​of η1 and η2 can be obtained.

[0156] In this embodiment of the disclosure, multiple sub-parameters of a substation are determined based on the Lyapunov function of the nominal system model, so that each substation can determine the corresponding first frequency boundary parameter and second frequency boundary parameter according to the corresponding multiple sub-parameters, thereby determining the lower frequency limit value of each substation.

[0157] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0158] For a better understanding of the embodiments of this application, see [link to relevant documentation]. Figure 8 and Figure 9This application provides a most complete embodiment. The master station can be located in the power grid dispatch center, and the substations can be located at each generating unit. It can be understood that one generating unit is connected to a node in the power grid, and one substation is located at one generating unit. The master station collects the voltage amplitude and voltage phase of each node in the power grid through the PMU measurement and communication system. The master station obtains the real-time topology map of the power grid and generates impedance data for each branch of the power grid by combining it with a historical parameter database. The master station obtains the maximum real-time feed-in power of a single UHVDC line and the real-time active power of the largest capacity generating unit in the system. The maximum value of these two values ​​is used to form a typical active power disturbance event, determining the active power deficit and the node (substation) where the event occurs. Based on the active power deficit and the substation where the disturbance event occurred, combined with the voltage amplitude, phase, and line impedance values ​​of the substation collected by the master station, the disturbance power allocation coefficient for each generating unit (i.e., each substation) in the entire network is calculated, and then the disturbed power allocation for each generating unit at the moment of disturbance is calculated. The master station sends the disturbed power allocation for each generating unit to the substation at each generating unit. The substation establishes a dynamic model of the generator unit with active power disturbance as input, based on the unit's inertia coefficient, damping coefficient, governor time constant, and unit regulation power. Simultaneously, it establishes a nominal system model with zero input. Based on the nominal system model, the substation constructs and solves Lyapunov equations to obtain the Lyapunov function and its derivative for the nominal system model. According to the Lyapunov function of the nominal system, it calculates the component parameters of the generator unit's frequency boundary parameters. The substation solves for frequency deviation and prime mover mechanical power deviation under different disturbance power conditions, forming different component parameters, and then obtains the first frequency boundary parameter. The substation receives the active power deficit under a preset disturbance event from the master station, calculates the substation's maximum frequency deviation (i.e., the first frequency drop value) according to the first frequency boundary parameter, and returns the maximum frequency deviation to the master station. After receiving the maximum frequency deviation from each substation, the master station can generate a frequency deviation distribution map for all units in the network, completing the system frequency fluctuation analysis.

[0159] Based on the same inventive concept, this application also provides a frequency boundary determination apparatus for implementing the frequency boundary determination method described above. The solution provided by this apparatus is similar to the implementation scheme described in the above method; therefore, the specific limitations in one or more frequency boundary determination apparatus embodiments provided below can be found in the limitations of the frequency boundary determination method described above, and will not be repeated here.

[0160] In one embodiment, see Figure 10 A frequency boundary determination device 1000 is provided. The frequency boundary determination device 1000 includes:

[0161] The disturbance acquisition module 1002 is used to acquire the active power deficit of a preset disturbance event;

[0162] The power calculation module 1004 is used to determine the disturbed power allocation of each substation based on the active power deficit and the disturbance power allocation coefficient of each substation.

[0163] The power allocation module 1006 is used to send the disturbed allocation power of any substation to the substation so that the substation can determine the frequency lower limit value of the substation according to the corresponding disturbed allocation power.

[0164] The aforementioned frequency boundary determination device acquires the active power deficit of a preset disturbance event; determines the disturbed allocated power of each substation based on the active power deficit and the disturbance power allocation coefficient of each substation; and sends the disturbed allocated power of any substation to the substation so that the substation can determine its frequency lower limit based on the corresponding disturbed allocated power. Compared to the traditional technology where the power grid operation center constructs a dynamic model of the entire system and collects frequency-related parameters such as inertia, damping, and primary frequency regulation of all units in the system in real time for calculation, the frequency boundary determination device provided in this application establishes an information interaction mode between the master station and the substations. After acquiring the active power deficit of the preset disturbance event, the master station sends the disturbed allocated power determined by the active power deficit and the disturbance power allocation coefficient of each substation to each substation so that each substation can determine its frequency lower limit based on the corresponding disturbed allocated power. This eliminates the need for the master station to acquire detailed parameters of all units in the entire network in real time, reducing the dependence on information from each unit, thus reducing the amount of parameters collected and the amount of calculation, and greatly improving the frequency calculation speed.

[0165] In one embodiment, the disturbance acquisition module 1002 is further configured to acquire multiple power generation capacities and acquire the DC feed-in power of each UHVDC line, wherein the multiple power generation capacities include the power generation capacities corresponding to each substation; take the maximum value among the multiple power generation capacities as the target power generation capacities; and take the maximum value between the DC feed-in power of each UHVDC line and the target power generation capacities as the active power deficit power of the preset disturbance event.

[0166] In one embodiment, the frequency boundary determination device 1000 further includes a coefficient determination module. The coefficient determination module is used to, for any given substation, acquire the voltage amplitude of the substation, the impedance value between the substation and the disturbing substation, and the voltage phase difference between the substation and the disturbing substation, where the disturbing substation is the substation that has experienced a preset disturbance event; and for any given substation, obtain the disturbance power allocation coefficient of the substation based on the voltage amplitude of the substation, the voltage amplitude of the disturbing substation, the impedance value between the substation and the disturbing substation, and the voltage phase difference between the substation and the disturbing substation.

[0167] In one embodiment, see Figure 11 A frequency boundary determination device 1100 is provided. The frequency boundary determination device 1100 includes:

[0168] The power receiving module 1102 is used to receive the disturbed allocated power sent by the master station. The disturbed allocated power is the power determined by the master station based on the active power deficit power of the preset disturbance event and the disturbance power allocation coefficient of each substation.

[0169] The frequency calculation module 1104 is used to determine the lower limit of the frequency of the substation based on the power allocated by the disturbance.

[0170] The aforementioned frequency boundary determination device receives the disturbed allocation power sent by the master station. This disturbed allocation power is determined by the master station based on the active power deficit of a preset disturbance event and the disturbance power allocation coefficients of each substation. Based on the disturbed allocation power, the lower frequency limit of each substation is determined. Compared to traditional technologies where the power grid operation center constructs a dynamic model of the entire system and collects frequency-related parameters such as inertia, damping, and primary frequency regulation of all units in the system in real time for calculation, the frequency boundary determination device provided in this application establishes an information interaction mode between the master station and substations. After obtaining the active power deficit of a preset disturbance event, the master station sends the disturbed allocation power determined by the active power deficit and the disturbance power allocation coefficients of each substation to each substation. This allows each substation to determine its own lower frequency limit based on the corresponding disturbed allocation power. This eliminates the need for the master station to obtain detailed parameters of all units in the entire network in real time, reducing its dependence on information from each unit, thus reducing the amount of parameters collected and the computational load, and significantly improving the frequency calculation speed.

[0171] In one embodiment, the frequency calculation module 1104 is further configured to determine the frequency boundary parameters of the substation based on the substation's inertial time constant, damping coefficient, governor time constant, and unit regulation power; determine the first frequency drop value of the substation based on the substation's frequency boundary parameters and the substation's disturbed distribution power; and obtain the substation's lower frequency limit value based on the frequency under steady-state conditions and the substation's first frequency drop value.

[0172] In one embodiment, the frequency calculation module 1104 is also used to determine multiple sub-parameters of the substation based on the substation's inertial time constant, damping coefficient, speed governor time constant, and unit regulation power; and to determine the substation's frequency boundary parameters based on the input-output stability BIBO theory and the multiple sub-parameters.

[0173] In one embodiment, the frequency calculation module 1104 is further configured to construct a nominal system model of the substation based on the substation's inertial time constant, damping coefficient, governor time constant, unit regulation power, frequency drop value of the substation, and change in prime mover input power of the substation; obtain the Lyapunov function of the nominal system model; and determine multiple sub-parameters of the substation based on the Lyapunov function, the frequency drop value of the substation, and change in prime mover input power of the substation.

[0174] Each module in the aforementioned frequency boundary determination device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0175] In one embodiment, this application also provides a frequency boundary determination system for implementing the frequency boundary determination method described above. The frequency boundary determination system includes a master station and multiple substations. The master station acquires the active power deficit of a preset disturbance event, determines the disturbed allocated power of each substation based on the active power deficit and the disturbance power allocation coefficient of each substation, and sends the disturbed allocated power of each substation to the respective substations. The substations receive the disturbed allocated power sent by the master station and determine the lower frequency limit of each substation based on the disturbed allocated power.

[0176] It should be noted that the process of determining the lower frequency limit value by the frequency boundary determination system in this application embodiment can be referred to the relevant description in the foregoing embodiment, and will not be repeated here in this application embodiment.

[0177] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 12 As shown, the computer device includes a processor, memory, and a network interface connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The network interface is used to communicate with external terminals via a network connection. When executed by the processor, the computer program implements a frequency boundary determination method.

[0178] Those skilled in the art will understand that Figure 12 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0179] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above-described method embodiments.

[0180] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps in the above method embodiments.

[0181] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0182] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0183] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0184] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0185] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for determining frequency boundaries, characterized in that, Applied to the main station, the method includes: Obtain the active power deficit for preset disturbance events; Based on the active power deficit and the disturbance power allocation coefficient of each substation, the disturbed allocation power of each substation is determined. For any of the aforementioned substations, the disturbed allocation power of the substation is sent to the substation so that the substation can determine its lower frequency limit based on the corresponding disturbed allocation power. The lower frequency limit of the substation is determined based on the substation's frequency boundary parameters and the disturbed allocation power. The frequency boundary parameters are determined based on the substation's inherent inertial time constant, damping coefficient, governor time constant, unit regulation power, and BIBO theory of input-output stability. The acquisition of the active power deficit of the preset disturbance event includes: The system acquires multiple power generation capacities and the DC feed-in power of each UHVDC line, wherein the multiple power generation capacities include the power generation capacities corresponding to each of the substations. The maximum value among the plurality of power generation powers is taken as the target power generation power; The maximum value between the DC feed-in power of each UHVDC line and the target power generation is taken as the active power deficit for the preset disturbance event.

2. The method according to claim 1, characterized in that, The method further includes: For any of the substations, the voltage amplitude of the substation, the impedance value between the substation and the disturbing substation, and the voltage phase difference between the substation and the disturbing substation are obtained, wherein the disturbing substation is the substation that has experienced the preset disturbance event; For any of the substations, the disturbance power allocation coefficient of the substation is determined based on the voltage amplitude of the substation, the voltage amplitude of the disturbance substation, the impedance value between the substation and the disturbance substation, and the voltage phase difference between the substation and the disturbance substation.

3. A method for determining frequency boundaries, characterized in that, Applied to a substation, the method includes: The system receives the disturbed allocated power sent by the master station. The disturbed allocated power is the power determined by the master station based on the active power deficit of a preset disturbance event and the disturbance power allocation coefficient of each substation. The acquisition of the active power deficit includes: the master station acquiring multiple generating powers and acquiring the DC feed-in power of each UHVDC line, wherein the multiple generating powers include the generating powers corresponding to each substation; the maximum value among the multiple generating powers is taken as the target generating power; and the maximum value between the DC feed-in power of each UHVDC line and the target generating power is taken as the active power deficit of the preset disturbance event. The lower frequency limit of the substation is determined based on the disturbed allocated power. The lower frequency limit of the substation is determined based on the frequency boundary parameters of the substation and the disturbed allocated power. The frequency boundary parameters are determined based on the inherent inertial time constant, damping coefficient, governor time constant, unit regulation power, and input-output stability BIBO theory of the substation.

4. The method according to claim 3, characterized in that, Determining the lower frequency limit of the substation based on the disturbed allocated power includes: Based on the inertial time constant, damping coefficient, governor time constant, and unit regulation power of the substation, determine the frequency boundary parameters of the substation; The first frequency drop value of the substation is determined based on the frequency boundary parameters of the substation and the disturbed allocated power of the substation. The lower frequency limit of the substation is obtained based on the frequency under steady-state conditions and the first frequency drop value of the substation.

5. The method according to claim 4, characterized in that, The determination of the frequency boundary parameters of the substation based on its inertial time constant, damping coefficient, governor time constant, and unit regulation power includes: Based on the inertial time constant, damping coefficient, governor time constant, and unit regulation power of the substation, multiple sub-parameters of the substation are determined. The frequency boundary parameters of the substation are determined based on the input-output stability BIBO theory and the multiple sub-parameters.

6. The method according to claim 5, characterized in that, Based on the substation's inertial time constant, damping coefficient, governor time constant, and unit regulation power, several sub-parameters of the substation are determined, including: Based on the inertial time constant, damping coefficient, governor time constant, unit regulation power of the substation, as well as the frequency drop value of the substation and the change in prime mover input power of the substation, construct the nominal system model of the substation; Obtain the Lyapunov function of the nominal system model; Based on the Lyapunov function, the frequency drop value of the substation, and the change in the prime mover input power of the substation, multiple sub-parameters of the substation are determined.

7. A frequency boundary determination device, characterized in that, The device is applied to the main station, and the device includes: The disturbance acquisition module is used to acquire the active power deficit of a preset disturbance event; The power calculation module is used to determine the disturbed power allocation of each substation based on the active power deficit and the disturbance power allocation coefficient of each substation. A power allocation module is used to send the disturbed allocated power of any of the substations to the substation, so that the substation can determine its lower frequency limit based on the corresponding disturbed allocated power. The lower frequency limit of the substation is determined based on the frequency boundary parameters of the substation and the disturbed allocated power. The frequency boundary parameters are determined based on the substation's inherent inertia time constant, damping coefficient, governor time constant, unit regulation power, and input-output stability BIBO theory. The disturbance acquisition module is also used to acquire multiple power generation capacities and acquire the DC feed-in power of each UHVDC line, wherein the multiple power generation capacities include the power generation capacities corresponding to each of the substations; the maximum value among the multiple power generation capacities is used as the target power generation capacities; and the maximum value between the DC feed-in power of each UHVDC line and the target power generation capacities is used as the active power deficit power of the preset disturbance event.

8. A frequency boundary determination system, characterized in that, The system includes: a main station and multiple substations, wherein, The master station is used to obtain the active power deficit of a preset disturbance event, determine the disturbed power allocation of each substation based on the active power deficit and the disturbance power allocation coefficient of each substation, and send the disturbed power allocation of each substation to each substation. The substation is used to receive the disturbed allocated power sent by the master station, and to determine the lower frequency limit of the substation based on the disturbed allocated power. The lower frequency limit of the substation is determined based on the frequency boundary parameters of the substation and the disturbed allocated power. The frequency boundary parameters are determined based on the inherent inertial time constant, damping coefficient, speed controller time constant, unit regulation power, and input-output stability BIBO theory of the substation. The main station is specifically used to acquire multiple power generation capacities and the DC feed-in power of each UHVDC line. The multiple power generation capacities include the power generation capacities corresponding to each of the substations. The maximum value among the multiple power generation capacities is taken as the target power generation capacities. The maximum value between the DC feed-in power of each UHVDC line and the target power generation capacities is taken as the active power deficit power of a preset disturbance event.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

Images