New energy station fault transient curve phased calculation method and device

Abstract

The application relates to the technical field of power system control, in particular to a new energy station fault transient curve phased calculation method and device, wherein the method comprises the following steps: dividing a new energy station fault process into a steady state stage, a mutation instant and a sub-transient transition stage, dividing the steady state stage into a pre-steady state stage, a fault quasi-steady state stage and a post-recovery steady state stage, then calculating a steady state value of the steady state stage, calculating a mutation initial value of the mutation instant, and calculating a sub-transient curve of the sub-transient transition stage, and further generating a new energy station fault transient curve based on the steady state value, the mutation initial value and the sub-transient curve. Therefore, the problem that related technologies need to establish a detailed model of equipment in a station, the calculation efficiency is limited, and the new energy station online optimization control is difficult to adapt is solved.

Description

Technical Field

[0001] This application relates to the field of power system control technology, and in particular to a method and apparatus for phased calculation of fault transient curves in new energy power plants. Background Technology

[0002] Driven by the strategic goals of "carbon peaking" and "carbon neutrality," the construction of a new power system with renewable energy as its mainstay is accelerating. Renewable energy is primarily connected to the grid through grid-connected converters, whose control methods can be broadly categorized into grid-following and grid-connecting types. Grid-following converters achieve synchronization with the grid by tracking the voltage phase at the grid connection point through a phase-locked loop (PLL), and are currently the dominant type of existing grid-connected converters. In high-proportion renewable energy power systems, when fault conditions such as low-voltage ride-through or high-voltage ride-through occur, renewable energy power plants need to have the ability to actively support the grid, including reactive power support (raising the grid connection point voltage through reactive current injection) and active power support (maintaining active power output and simulating inertia response). The transient behavior characteristics of renewable energy power plants during faults directly determine the magnitude of their active support capability and the level of grid disconnection risk.

[0003] In related technologies, the main method for obtaining transient curves of faults in renewable energy power plants is time-domain simulation based on detailed electromagnetic transient models. This method requires establishing detailed models of each converter, transformer, line, and other equipment within the power plant, and using small-step numerical integration to solve differential-algebraic equations, resulting in large computational loads and long processing times. Taking a typical renewable energy power plant containing dozens of converters as an example, completing an electromagnetic transient simulation of a complete fault scenario typically takes several minutes or even longer. Furthermore, when it is necessary to evaluate the power plant response under different combinations of control parameters and different fault scenarios, a large number of repetitive simulations are required, further amplifying the computational overhead. Since online optimization control of renewable energy power plants needs to complete the entire process from measurement data to evaluation index calculation and control decision generation within a second-level timescale, and the computational efficiency of related technologies is limited, they cannot serve as rapid evaluation tools in online optimization, which urgently needs to be addressed. Summary of the Invention

[0004] This application provides a method and apparatus for phased calculation of transient curves of faults in new energy power stations, in order to solve the problem that related technologies require the establishment of detailed models of equipment within the power station, resulting in limited calculation efficiency and difficulty in adapting to online optimization control of new energy power stations.

[0005] The first aspect of this application provides a method for calculating the transient curve of a new energy power station fault in stages, including the following steps: dividing the fault process of the new energy power station into a steady-state stage, a sudden change moment, and a sub-transient transition stage, and further dividing the steady-state stage into a pre-steady-state stage, a fault quasi-steady-state stage, and a post-recovery steady-state stage; calculating the steady-state value of the steady-state stage, calculating the initial value of the sudden change moment, and calculating the sub-transient curve of the sub-transient transition stage; and generating the fault transient curve of the new energy power station based on the steady-state value, the initial value of the sudden change, and the sub-transient curve.

[0006] Based on the above technical means, this application embodiment divides the fault process of new energy power stations into a steady-state stage, an instantaneous change, and a sub-transient transition stage. The steady-state stage is further subdivided into a pre-steady-state stage, a fault quasi-steady-state stage, and a post-recovery steady-state stage. After solving the corresponding steady-state values, initial values ​​of the sudden change, and sub-transient curves hierarchically, a complete fault transient curve is generated. This can adapt differentiated calculation logic according to the electrical dominant laws of different fault periods, significantly reducing the calculation time of a single fault scenario. When facing the batch evaluation needs of multiple fault conditions and multiple sets of equipment control parameters, it can also significantly reduce the computing power overhead caused by repeated calculations. The obtained fault transient curve can be output in seconds or even milliseconds, which can directly adapt to the real-time calculation needs of online optimization control of new energy power stations, providing reliable and rapid evaluation support for online control decisions.

[0007] Optionally, in one embodiment of this application, before dividing the fault process of the new energy power station into the steady-state stage, the instantaneous change, and the sub-transient transition stage, the method further includes: establishing the main circuit topology of the new energy power station; establishing the equipment equations, bus current equations, and bus line equations of the new energy power station to determine the steady-state equation set of the new energy power station.

[0008] Based on the above technical means, the embodiments of this application establish the main circuit topology of the new energy power station in advance and construct equipment equations, bus current equations, and bus line equations to form a set of steady-state equations for the power station. This can accurately adapt to the actual grid connection structure and electrical constraint relationship of the new energy power station, and can adapt to multiple types of grid-connected equipment and fault scenarios. It ensures the standardization and consistency of the phased calculation of the entire process, effectively supports the efficient implementation of subsequent directional recursion and simplified modeling, and improves the accuracy and adaptability of the overall fault transient curve calculation results.

[0009] Optionally, in one embodiment of this application, calculating the steady-state value of the steady-state stage includes: obtaining the line parameters and control parameters of the new energy power station, and obtaining the grid parameters of the external power grid; calculating the steady-state value of the electrical quantity based on the line parameters, the control parameters, the grid parameters, and the equipment equations, so as to determine the steady-state value of the steady-state stage.

[0010] Based on the above technical means, the embodiments of this application collect the station line parameters, equipment control parameters and external power grid parameters, and combine the equipment equations to solve the steady-state values ​​of electrical quantities in each steady-state stage. It can restore the steady-state operating conditions of the station based on the actual operating parameters, obtain steady-state electrical data that fits the real grid connection scenario, and at the same time provide reliable basic data support for the calculation of subsequent initial values ​​of sudden changes and sub-transient curves.

[0011] Optionally, in one embodiment of this application, calculating the initial value of the sudden change at the instant of the sudden change includes: calculating the initial value of the sudden change of the bus voltage based on the power grid parameters and the bus line equation; calculating the initial value of the sudden change of the equipment terminal voltage based on the initial value of the sudden change of the bus voltage and the equipment equation; and determining the initial value of the sudden change at the instant of the sudden change based on the initial value of the sudden change of the bus voltage and the initial value of the sudden change of the equipment terminal voltage.

[0012] Based on the above technical means, the embodiments of this application solve the initial value of bus voltage change by relying on power grid parameters and bus line equations, and then recursively obtain the initial value of equipment terminal voltage change by combining equipment equations. By integrating multi-dimensional electrical quantities, the initial value of the instantaneous change is determined. This can follow the electrical transmission law at the instant of fault change and accurately restore the instantaneous electrical state of the bus and equipment side after the power grid voltage change. It can provide accurate initial boundary conditions for the accurate deduction of subsequent sub-transient transition curves.

[0013] Optionally, in one embodiment of this application, calculating the sub-transient curve of the sub-transient transition stage includes: generating equipment sub-transient curves based on the control characteristics of the equipment in the new energy power station; recursively deriving the equipment equation, the bus current equation, and the bus line equation based on the equipment sub-transient curves to derive the electrical quantity curve from the equipment to the bus; and determining the sub-transient curve of the sub-transient transition stage based on the electrical quantity curves.

[0014] Based on the above technical means, the embodiments of this application generate equipment sub-transient curves by combining equipment control characteristics, and then directionally deduce equipment equations, bus current equations, and bus line equations. The entire electrical quantity curves are derived layer by layer from the equipment side to the bus side, and the complete sub-transient curves are determined. This can fit the transient response characteristics of new energy equipment, truly reflect the electrical change law of the fault transition process, and effectively improve the generation efficiency of sub-transient curves without the need for complex simultaneous iterative calculations across the entire network.

[0015] A second aspect of this application provides a device for calculating the staged transient curve of a new energy power station fault, comprising: a division module for dividing the fault process of the new energy power station into a steady-state stage, a sudden change moment, and a sub-transient transition stage, and further dividing the steady-state stage into a pre-steady-state stage, a fault quasi-steady-state stage, and a post-recovery steady-state stage; a calculation module for calculating the steady-state value of the steady-state stage, calculating the initial value of the sudden change moment, and calculating the sub-transient curve of the sub-transient transition stage; and a generation module for generating the fault transient curve of the new energy power station based on the steady-state value, the initial value of the sudden change, and the sub-transient curve.

[0016] Optionally, in one embodiment of this application, it further includes: a first establishment module, used to establish the main circuit topology of the new energy power station; and a second establishment module, used to establish the equipment equations, bus current equations, and bus line equations of the new energy power station, so as to determine the steady-state equation set of the new energy power station.

[0017] Based on the above technical means, the embodiments of this application establish the main circuit topology of the new energy power station in advance and construct equipment equations, bus current equations, and bus line equations to form a set of steady-state equations for the power station. This can accurately adapt to the actual grid connection structure and electrical constraint relationship of the new energy power station, and can adapt to multiple types of grid-connected equipment and fault scenarios. It ensures the standardization and consistency of the phased calculation of the entire process, effectively supports the efficient implementation of subsequent directional recursion and simplified modeling, and improves the accuracy and adaptability of the overall fault transient curve calculation results.

[0018] A third aspect of this application provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and capable of running on the processor. The processor executes the program to implement the phased calculation method for transient fault curves of new energy power stations as described in the above embodiments.

[0019] A fourth aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method for phased calculation of transient curves for faults in new energy power stations.

[0020] The fifth aspect of this application provides a computer program product, including a computer program that, when executed, implements the above-described method for phased calculation of transient curves of faults in new energy power stations.

[0021] Based on the above technical means, this application embodiment divides the fault process of a new energy power station into a steady-state stage, an instantaneous change, and a sub-transient transition stage. The steady-state stage is further subdivided into a pre-steady-state stage, a fault quasi-steady-state stage, and a post-recovery steady-state stage. After solving the corresponding steady-state values, initial values ​​of the sudden change, and sub-transient curves hierarchically, a complete fault transient curve is generated. This allows for adaptation to differentiated calculation logic based on the dominant electrical laws at different fault times, significantly reducing the calculation time for a single fault scenario. When facing the need for batch evaluation of multiple fault conditions and multiple sets of equipment control parameters, it also significantly reduces the computational overhead caused by repetitive calculations. The obtained fault transient curve can be output in seconds or even milliseconds, directly adapting to the real-time calculation requirements of online optimization control of new energy power stations, providing reliable and rapid evaluation support for online control decisions. Therefore, it solves the problem that related technologies require the establishment of detailed models of equipment within the power station, resulting in limited computational efficiency and difficulty in adapting to online optimization control of new energy power stations.

[0022] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0023] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a flowchart illustrating a method for phased calculation of transient fault curves at a new energy power station, according to an embodiment of this application. Figure 2 This is a schematic diagram of the main circuit topology of a new energy power station according to an embodiment of this application; Figure 3 This is a schematic diagram illustrating the angular relationship of some variables according to an embodiment of this application; Figure 4 This is a schematic diagram illustrating the stage division of a low-voltage ride-through fault curve according to an embodiment of this application; Figure 5 This is a schematic diagram of a phased calculation method for transient curves of new energy power station faults according to an embodiment of this application; Figure 6 This is a schematic diagram illustrating the phase relationship between the bus voltage and the equipment terminal voltage after a sudden change, according to an embodiment of this application. Figure 7 This is a flowchart of a method for calculating the transient curve of a new energy power station fault in stages according to an embodiment of this application; Figure 8 This is a block diagram of a phased calculation device for transient fault curves of new energy power stations provided in an embodiment of this application; Figure 9This is a schematic diagram of the structure of an electronic device provided according to an embodiment of this application.

[0024] Figure label: 80-Phase calculation device for transient curves of faults in new energy power plants; 100-Division module, 200-Calculation module, 300-Generation module; 901-Memory, 902-Processor, 903-Communication interface. Detailed Implementation

[0025] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0026] Based on the background description, the relevant technology has the following shortcomings.

[0027] First, the computation speed is slow, which cannot meet the needs of online applications. Related technologies require solving large-scale differential-algebraic equation systems with small step sizes, and each simulation takes a long time, making it difficult to embed into online optimization control frameworks that need to complete decisions in the second range.

[0028] Second, there is a lack of phased simplification methods geared towards computational efficiency. Related technologies simulate and solve the entire fault process uniformly, without utilizing the different physical characteristics of each stage for targeted simplification. In reality, the fault process can be clearly divided into a steady-state stage, abrupt change, and a transient transition stage. Each stage has different dominant physical factors, allowing for the adoption of different simplification strategies.

[0029] Third, the structural features of the power plant topology and equations were not fully utilized for acceleration. New energy power plants have a typical star network topology (each device is connected to the bus via impedance, and the bus is then connected to the power grid via impedance), and their physical equations can be decomposed into three sets: device equations, bus current equations, and bus line equations. Each set of equations has a clear computational directionality, but related technologies have not utilized these structural features to simplify calculations.

[0030] Fourth, there is a lack of simplified curve calculation schemes that can provide rapid feedback for online optimization. In online optimization, full details of the fault curve are often not required; instead, simplified transient curves that reflect key characteristics of offline risk and support capabilities are needed. Related technologies offer accuracy beyond what is required, but at an unnecessary cost in time.

[0031] To address the shortcomings of related technologies, this application proposes a method and apparatus for phased calculation of transient curves of faults in new energy power stations.

[0032] The following describes a method and apparatus for calculating the staged transient curve of a new energy power station fault, based on embodiments of the present application, with reference to the accompanying drawings. The main idea is to divide the fault process of a new energy power station into a steady-state stage, a sudden change instant, and a sub-transient transition stage. Differentiated simplified calculation strategies are adopted for the different physical characteristics of each stage, and directional decoupling calculations are performed using the structural characteristics of the power station equations, thereby significantly reducing the computational load and enabling rapid acquisition of the fault transient curve.

[0033] Figure 1 This is a flowchart of a method for calculating the transient curve of a new energy power station fault in stages, according to an embodiment of this application.

[0034] like Figure 1 As shown, the phased calculation method for the fault transient curve of the new energy power station includes the following steps: In step S101, the fault process of the new energy power station is divided into a steady-state stage, a sudden change moment and a sub-transient transition stage, and the steady-state stage is further divided into a pre-steady-state stage, a fault quasi-steady-state stage and a post-recovery steady-state stage.

[0035] Optionally, in one embodiment of this application, before dividing the fault process of the new energy power station into a steady-state stage, a sudden change moment, and a sub-transient transition stage, the method further includes: establishing the main circuit topology of the new energy power station; establishing the equipment equations, bus current equations, and bus line equations of the new energy power station to determine the steady-state equation set of the new energy power station.

[0036] In actual implementation, the embodiments of this application first establish the main circuit topology of the new energy power station, and then establish the equipment equations, bus current equations, and bus line equations of the new energy power station to determine the steady-state equation set of the new energy power station.

[0037] like Figure 2 The diagram illustrates the main circuit topology of a renewable energy power plant. Renewable energy generation units (such as photovoltaic + inverters), SVG (Static Var Generator), energy storage, and other equipment within the plant are connected to the plant's outlet busbar via step-up transformers and lines. From there, the voltage is further boosted and connected to the external power grid. After accounting for different voltage levels, the transformer can be considered as an impedance. Therefore, the entire system can be viewed as a star network structure where all equipment within the plant is connected to the busbar via impedance, and the busbar is then connected to the external power grid via impedance. Since there may be a large number of generation units within the plant, they can be grouped and equivalently represented as a smaller number of devices.

[0038] Furthermore, this application embodiment utilizes the equipment equations, bus current equations, and bus line equations of the new energy power station to construct a steady-state equation set. These three equations are all derived from the dq decomposition of a three-phase AC system. The variables in the equations are divided into equipment variables, which have a set for each device, and power station variables, which have only one set for the entire power station system. Variables marked with an apostrophe indicate that the bus voltage phase is used as the d-axis phase; variables without an apostrophe indicate that the voltage phase of each device is used as the d-axis phase.

[0039] The representation and meaning of device variables are as follows.

[0040] This refers to the voltage amplitude at the device terminals. The amplitude of the device's output current; The power factor angle of the equipment ( Leading From the perspective of leading (positive). The phase angle between the equipment terminal voltage and the bus voltage (the angle by which the equipment terminal voltage leads the bus voltage, with leading being positive); The d-axis component of the equipment output current when the bus voltage phase is taken as the d-axis phase; The q-axis component of the equipment output current when the bus voltage phase is taken as the d-axis phase; The resistance of the device's output line; This refers to the reactance of the equipment's output line.

[0041] The representation and meaning of the station variables are as follows.

[0042] This refers to the amplitude of the bus voltage. When the bus voltage phase is taken as the d-axis phase, the d-axis component of the current flowing from the bus to the grid; When the bus voltage phase is taken as the d-axis phase, the q-axis component of the current flowing from the bus to the grid; The phase angle between the grid voltage and the bus voltage (the angle by which the bus voltage leads the grid voltage, with leading being positive); This refers to the voltage amplitude of the power grid. The resistance of the station's output line; This refers to the output line reactance of the station.

[0043] like Figure 3 As shown in the figure, the angular relationship of some variables is illustrated. As can be seen from the figure, when the d-axis of the device output current is transformed from the phase of the device's own voltage to the phase of the bus voltage, the transformation relationship is as shown in equations (1) and (2).

[0044] When the phase of the device's own voltage is taken as the d-axis phase, the expression for the dq-axis component of the device's output current can be, but is not limited to, as follows: (1) When the bus voltage phase is taken as the d-axis phase, the expression for the dq-axis component of the equipment output current can be, but is not limited to, as follows: (2) Based on the above explanation, it can be understood that... , According to , , , Therefore, when the site contains n devices, the total number of main variables is 4n+4, including 4n device variables. , , , ) and 4 station variables ( , , , ). In line impedance ( , , , ) and grid voltage When the parameters are fixed, the state of the station can be described based on the subsequent three equations.

[0045] Equipment equations describe the relationship between the output voltage and current of each device and the line impedance, and can be further divided into two sets: equipment control equations and equipment line equations. The equipment control equations describe the control equations for the active and reactive current outputs of the device under steady-state conditions, neglecting factors such as the current inner loop. The equipment line equations describe the relationship between line impedance, voltage, and current under the d-axis and q-axis in steady-state conditions. The equipment equations actually use the phase of each device's phase-locked loop as the d-axis phase, but in steady-state, the phase of the device's phase-locked loop is the phase of the device's own voltage. .

[0046] The expression for the equipment control equation can be, but is not limited to, as follows: (3) in, and These represent the active and reactive current control equations in equipment control, respectively. The settings may differ at different stages, which will be further explained in the subsequent calculation process.

[0047] The expression for the equipment circuit equation can be, but is not limited to, as follows: (4) in, and The dq-axis components of the device terminal voltage are defined as follows: when the phase of the device's own voltage is taken as the d-axis phase, the terminal voltage of the device is defined as follows.

[0048] The bus current equation refers to the equation representing the convergence of the output currents of various devices at the bus. Under dq decomposition, a unified coordinate system is needed for convergence. Therefore, the output currents of each device need to be unified to a coordinate system where the bus voltage phase is used as the d-axis phase, and then the calculations are performed separately along the dq axes. The expression for the bus current equation can be, but is not limited to, as follows: (5) in, Total number of devices; For device indexing; and The first When the bus voltage phase is the d-axis phase, the device outputs the current dq-axis component.

[0049] The bus line equation describes the d-axis impedance-voltage-current relationship of the line between the bus and the grid in steady state. This equation uses the bus voltage phase as the d-axis phase, therefore it always holds... The expression for the busbar circuit equation can be, but is not limited to, as follows: (6) Equations (3), (4), (5), and (6) together constitute the quasi-steady-state equations of the station. For a station with n devices, each device corresponds to the four equations in equations (3) and (4), and the total number of equations for n devices is 4n. In addition, there are the four equations in equations (5) and (6), so the station has a total of 4n+4 equations. This set of equations corresponds to the 4n+4 main variables that describe the state of the station.

[0050] This application embodiment establishes the main circuit topology of the new energy power station in advance and constructs equipment equations, bus current equations, and bus line equations to form a set of steady-state equations for the power station. This can accurately adapt to the actual grid connection structure and electrical constraint relationship of the new energy power station, and can adapt to multiple types of grid-connected equipment and fault scenarios. It ensures the standardization and consistency of the phased calculation throughout the entire process, effectively supports the efficient implementation of subsequent directional recursion and simplified modeling, and improves the accuracy and adaptability of the overall fault transient curve calculation results.

[0051] Based on the above description, the embodiments of this application divide the fault process of new energy power stations into a steady-state stage, a sudden change moment and a sub-transient transition stage, and further divide the steady-state stage into a pre-steady-state stage, a fault quasi-steady-state stage and a post-recovery steady-state stage.

[0052] This application uses changes in grid voltage to represent the impact of external faults on the substation. This impact is reflected in two aspects: first, in the grid voltage amplitude change curves of the pre-coverage steady-state stage, the fault quasi-steady-state stage, and the post-recovery steady-state stage, the grid voltage maintains a drop amplitude during the fault quasi-steady-state stage; second, the grid voltage angle changes abruptly when the fault occurs and ends.

[0053] Taking low voltage ride-through as an example, such as Figure 4 As shown, the low-voltage ride-through fault curve is divided into stages. It can be further subdivided into the pre-fault steady-state stage, the fault sub-transient stage, the fault quasi-steady-state stage, the recovery sub-transient stage, and the post-recovery steady-state stage. The fault quasi-steady-state stage refers to the plateau range where electrical quantities tend to stabilize in the later stages of the fault phase. The sub-transient stage refers to the range where electrical quantities change significantly between the previous steady state and the next steady state.

[0054] In step S102, the steady-state value of the steady-state stage is calculated, the initial value of the sudden change is calculated at the instant of the sudden change, and the sub-transient curve of the sub-transient transition stage is calculated.

[0055] like Figure 5 As shown, the embodiments of this application can calculate the steady-state value in the steady-state stage, the initial value of the sudden change at the moment of sudden change, and the sub-transient curve of the sub-transient transition stage, given the station data and external power grid fault data, so as to construct the fault curve.

[0056] Optionally, in one embodiment of this application, calculating the steady-state value in the steady-state stage includes: obtaining the line parameters and control parameters of the new energy power station, and obtaining the grid parameters of the external power grid; and calculating the steady-state value of the electrical quantity based on the line parameters, control parameters, grid parameters, and equipment equations to determine the steady-state value in the steady-state stage.

[0057] For steady-state value calculation, steady state refers to the pre-steady state, fault quasi-steady state, and post-recovery steady state. It is a state where external and control parameters remain essentially unchanged over a certain period, and the entire system reaches a stable state. Calculating a set of state variables at a given moment represents the state of the entire steady-state process. Based on the 4n+4 main variables describing the station state and the 4n+4 equations describing steady state, given the parameter values ​​(excluding the main variables) in the equation set, the various steady-state state variables can be obtained by solving the equation set. It is known that the equipment equations actually use the phase-locked loop (PLL) phase of each device as the d-axis phase, but in steady state, the PLL phase of the device is the phase of its own voltage. Other steady-state parameters that need to be given are shown in Table 1.

[0058] Table 1

[0059] In pre-steady-state calculations, if given active and reactive current command values ​​can be obtained, such as in a simulation scenario, the expression for the corresponding equipment control equations can be, but is not limited to, as follows: (7) in, This is the active current command value. This is the reactive current command value.

[0060] If the corresponding command value cannot be obtained, but the amplitude of the device terminal voltage under the pre-steady-state condition can be collected, then... and the active power output of the equipment Equipment output reactive power (All subsequent references to reactive power) The calculations (assuming inductive reactive power, which will not be repeated here) can be performed using these quantities to indirectly obtain the corresponding command values. The expression for the equipment control equation can be, but is not limited to, as follows: (8) in, To output active power to the equipment, It outputs reactive power to the equipment.

[0061] Substituting equation (7) or (8) into equation (3), and simultaneously solving equations (3), (4), (5), and (6), the steady-state values ​​of the electrical quantities at various points in the system can be obtained, including... , , , , , , , .

[0062] In fault quasi-steady-state calculations, the corresponding equipment control equations are obtained with reference to relevant national standards. For example, during low-voltage ride-through, the expression of the equipment control equations may be, but is not limited to, the following: (9) in, This refers to the active current in the pre-steady state. This refers to the reactive current in the pre-steady-state state. To maintain the original work ratio, This is the reactive power compensation factor for low voltage ride-through.

[0063] In the steady-state calculation after recovery, the equipment control equations are divided into two forms: one is to directly use the control equations of the steady state before the fault, and the other is the control equations for the output to be restored according to a certain proportion.

[0064] Based on the above explanation, it can be understood that, unlike the pre-steady state, when the pre-steady state is known, the equipment control equations for the fault quasi-steady state and the post-recovery steady state can generally be given directly, and the corresponding steady-state values ​​can be obtained by combining (3), (4), (5), and (6).

[0065] This application embodiment collects station line parameters, equipment control parameters, and external power grid parameters, and combines them with equipment equations to solve for the steady-state values ​​of electrical quantities at each steady-state stage. It can reconstruct the steady-state operating conditions of the station based on actual operating parameters, obtain steady-state electrical data that fits the real grid connection scenario, and provide reliable basic data support for the subsequent calculation of initial values ​​of sudden changes and sub-transient curves.

[0066] Optionally, in one embodiment of this application, calculating the initial value of the sudden change at the instant of the sudden change includes: calculating the initial value of the sudden change of the bus voltage based on the power grid parameters and the bus line equation; calculating the initial value of the sudden change of the equipment terminal voltage based on the initial value of the sudden change of the bus voltage and the equipment equation; and determining the initial value of the sudden change at the instant of the sudden change based on the initial value of the sudden change of the bus voltage and the initial value of the sudden change of the equipment terminal voltage.

[0067] It should be noted that the amplitude and angle of the grid voltage will change abruptly at the moment of fault occurrence and recovery, which will lead to abrupt changes in bus voltage and equipment terminal voltage. Therefore, the initial value of the transient process should not be directly taken from the value of the previous steady-state stage, but should be calculated based on the grid voltage change.

[0068] For renewable energy power plants, the lines within the plant and the transmission lines are typically overhead lines. The line-to-ground capacitance is relatively small, and they can be considered as a series resistor-inductor model. At the instant of a sudden change in grid voltage, the current in the line can be assumed to remain constant due to inductance, while the voltage at the busbar and equipment changes abruptly. Simultaneously, since the phase-locked loops (PLLs) of the equipment do not have time to activate during the instant of the change, the d-axis of the busbar and each piece of equipment is still based on the previous phase when calculating initial values. Based on this premise, the electrical quantities at various points at the instant of fault occurrence and recovery can be calculated using the following method.

[0069] Sudden changes in grid voltage amplitude can be used to measure the voltage amplitude of the faulted grid. This indicates that, for sudden changes in grid voltage angle, the bus line equation shown in equation (6) is... The phase angle between the grid voltage and the bus voltage is updated after a sudden change. ,in, The angle of the voltage surge in the power grid. Surge parameter. and Provided based on the fault condition.

[0070] Since the grid voltage on the left side of the bus line equation changes at the instant of abrupt change, while the line impedance and current on the right side remain unchanged, the initial value of the bus voltage change can be calculated based on the bus line equation. During this calculation, the d-axis phase is still the bus voltage phase from the pre-steady-state state. Taking the instant of a fault as an example, the expression for the bus line equation when the phase remains unchanged at the instant of the change can be, but is not limited to, as follows: (10) in, and The dq-axis components of the fault grid voltage are defined as follows: when the bus voltage phase in the pre-steady state is taken as the d-axis phase. The voltage amplitude of the faulty power grid; The angle of sudden voltage change in the power grid; and Let dq be the initial values ​​of the sudden change in the bus voltage when the phase of the bus voltage in the pre-steady state is taken as the d-axis phase. and These are the dq-axis components of the current flowing from the bus to the grid, with the bus voltage phase in the pre-steady state as the d-axis phase. Variables marked with superscript apostrophes indicate that the bus voltage phase in the pre-steady state is used as the d-axis phase.

[0071] Calculated from equation (10) and The amplitude of the bus voltage after the sudden change can be obtained. Angle of bus voltage change . and The expressions are as follows: (11) in, This represents the amplitude of the bus voltage after the sudden change. When the phase of the bus voltage in the pre-steady state is taken as the d-axis phase, the d-axis component of the bus voltage after the abrupt change is... The angle of the sudden change in bus voltage.

[0072] Next, align the busbar d-axis with the busbar voltage, i.e., rotate the busbar d-axis. At this time, the bus current rotates. The expression for bus current can be, but is not limited to, as follows: (12) After a sudden change in grid voltage, the disturbance will be transmitted to the terminal voltage of each device through the bus voltage change. The initial value of the sudden change in the terminal voltage of the devices needs to be calculated based on the bus voltage after the change. Equation (11) can be used to calculate the bus voltage after the change, combined with... Figure 6The phase relationship between the bus voltage and the equipment terminal voltage after the abrupt change is shown. The expression for the phase angle between the equipment terminal voltage and the bus voltage after the abrupt change can be, but is not limited to, as follows: (13) in, This is the phase angle between the equipment terminal voltage and the bus voltage after the sudden change.

[0073] Since the phase-locked loop (PLL) remains unchanged at the instant of the sudden change, and the d-axis phase also remains unchanged, the impedance and current on the right side of the equipment circuit equation do not change. Therefore, the initial value of the sudden change in the equipment terminal voltage can be calculated based on the equipment circuit equation. At this time, the PLL has not yet tracked the equipment terminal voltage after the sudden change, and the q-axis component of the equipment terminal voltage is not zero. The expression of the equipment circuit equation at the instant of the sudden change can be, but is not limited to, as follows: (14) in, and These are the initial values ​​of the sudden change in the terminal voltage of the equipment, representing the dq-axis components.

[0074] Based on the above explanation, according to equations (11) and (14), given the sudden change parameters at the moment of fault occurrence and recovery, the initial value of voltage sudden change at each location can be calculated according to the direction of the power grid, bus, and equipment.

[0075] This application embodiment solves for the initial value of bus voltage change by relying on power grid parameters and bus line equations, and then obtains the initial value of equipment terminal voltage change by recursively combining equipment equations. By integrating multi-dimensional electrical quantities, the initial value of the instantaneous change is determined. This can follow the electrical transmission law at the instant of fault change and accurately restore the instantaneous electrical state of the bus and equipment side after the power grid voltage change. It can provide accurate initial boundary conditions for the accurate deduction of subsequent sub-transient transition curves.

[0076] Optionally, in one embodiment of this application, calculating the sub-transient curve of the sub-transient transition stage includes: generating equipment sub-transient curves based on the control characteristics of equipment in the new energy power station; recursively deriving equipment equations, bus current equations, and bus line equations based on the equipment sub-transient curves to derive electrical quantity curves from equipment to bus; and determining the sub-transient curve of the sub-transient transition stage based on the electrical quantity curves.

[0077] Based on the descriptions of other embodiments, the embodiments of this application can solve for the steady-state value and the initial value of the sudden change in the fault curve. However, it is still necessary to supplement the calculation of the sub-transient curve between the initial value of the sudden change and the next steady state. The transient process of the station is mainly dominated by the control characteristics of each piece of equipment. The solution process is to first simplify to obtain the sub-transient curve of a single piece of equipment, and then recursively deduce the equipment line equation, bus current equation, and bus line equation, and derive the electrical quantity curves at each point from the equipment to the bus.

[0078] For grid-connected equipment, during the sub-transient process, its control characteristics are mainly reflected in the inner current loop and the phase-locked loop. Based on this, a simplified dq-axis current curve and the phase angle between the equipment terminal voltage and the bus voltage can be constructed. The curve is shown. To achieve rapid calculation, the electromagnetic transient differential process of the line is ignored, and the line relationship is treated as a time-by-time quasi-steady-state algebraic equation. The transient dominant factors are given by the equipment current inner loop and phase-locked loop. To eliminate complex oscillations and highlight the overall trend of change, one method is to use a straight line to connect the initial value of the sudden change and the steady-state value of the next stage as a sub-transient curve.

[0079] First, based on the PI parameters of the device controller or the simulation calibration results, obtain the transient duration of the device's inner current loop. Transient duration of phase-locked loop .

[0080] Next, taking the fault sub-transient as an example, and combining the previously obtained pre-steady-state value and fault quasi-steady-state value, a simplified dq-axis current curve and the phase angle between the equipment terminal voltage and the bus voltage are generated. The curves. dq-axis current curves, phase angle between equipment terminal voltage and bus voltage. The expressions for the curves are as follows: (15) in, The current curve is shown on the d-axis. This is the q-axis current curve; The phase angle between the equipment terminal voltage and the bus voltage The curve; The time is defined as the moment when the fault occurs, with the moment being time 0. The transient duration of the device's inner current loop; This represents the transient duration of the phase-locked loop (PLL) of the device. , The current is in the pre-steady state. and For the fault quasi-steady-state current, these quantities can be obtained from the calculated steady-state values ​​combined with equation (1). The angle between the phase of the equipment voltage and the phase of the bus voltage after the sudden change can be obtained according to equation (13). This is the angle between the phase of the equipment voltage and the phase of the bus voltage in the quasi-steady state of the fault. This value can be obtained directly from the steady-state value.

[0081] If we calculate the recovery subtransient process, then in equation (15) , Replace with , ,Will , Replace with the current in the recovered steady state , ,Will Change to the initial value of the sudden change at the moment of fault recovery. ,Will The angle between the phase of the equipment voltage and the phase of the bus voltage after recovery to the steady state .

[0082] After obtaining the equipment sub-transient curve, derive the electrical quantity curves at each location: first, rotate the equipment current in equation (15) to the bus coordinate system according to equation (2), and then substitute it into the bus current equation (5) to obtain the bus current curve. , Then, substituting the equations into the bus line equation (6), the bus voltage curve is obtained. Phase angle curve between grid voltage and bus voltage Then, by substituting the equations of the equipment circuit (4), the d-axis and q-axis component curves of the equipment terminal voltage are obtained. , Synthesis equipment terminal voltage amplitude curve .

[0083] This application embodiment generates equipment sub-transient curves by combining equipment control characteristics, and then recursively derives equipment equations, bus current equations, and bus line equations. It derives the full-domain electrical quantity curves layer by layer from the equipment side to the bus side and determines the complete sub-transient curves. This can fit the transient response characteristics of new energy equipment, truly reflect the electrical change law of the fault transition process, and effectively improve the generation efficiency of sub-transient curves without the need for complex simultaneous iterative calculations across the entire network.

[0084] In step S103, the fault transient curve of the new energy power station is generated based on the steady-state value, the initial value of the sudden change, and the sub-transient curve.

[0085] Continue as Figure 5 As shown, the overall fault transient curve can be obtained by combining the steady-state value, initial value of sudden change, equipment sub-transient curve, and electrical quantity curves at various points calculated in the embodiments of this application.

[0086] like Figure 7 As shown below, the principle of the phased calculation method for the transient curve of a new energy power station fault is illustrated with a specific embodiment.

[0087] In this embodiment, the line parameters, control parameters, and fault grid parameters of the new energy power station are first obtained. Based on the main circuit topology of the power station, an equivalent electrical model is constructed to determine the equipment equations, bus current equations, and bus line equations, which are then combined to form a set of steady-state equations for the new energy power station.

[0088] Furthermore, in this embodiment of the application, the target fault scenarios of low voltage ride-through or high voltage ride-through are combined to determine the grid voltage amplitude and phase change parameters, and the complete fault process is divided into a steady-state stage, a sudden change moment and a sub-transient transition stage. The steady-state stage is further subdivided into a pre-steady-state stage, a fault quasi-steady-state stage and a post-recovery steady-state stage.

[0089] Furthermore, in this embodiment, for the pre-steady-state stage, the fault quasi-steady-state stage, and the post-recovery steady-state stage, the station line parameters, equipment control parameters, and external power grid parameters are substituted into the station steady-state equations in combination with the equipment equations to obtain the steady-state values ​​of electrical quantities corresponding to each steady-state stage.

[0090] Furthermore, in this embodiment of the application, for two types of sudden changes—fault occurrence and fault recovery—it follows a directional recursive logic from the power grid to the bus and then to the equipment. It solves for the initial value of the bus voltage change based on the bus line equation, and then calculates the initial value of the voltage change at the terminal of each equipment by combining the equipment equation. Finally, it integrates the electrical data of the bus and equipment sides to obtain a complete set of initial values ​​of the sudden change.

[0091] Furthermore, in this embodiment, a simplified current sub-transient curve for a single device is generated based on the control characteristics of the grid-connected device itself. Then, the device equation, bus current equation, and bus line equation are recursively derived in a directional manner. The electrical timing curve of the entire domain is derived layer by layer from the device side to the bus side, thereby determining the sub-transient curve corresponding to the complete sub-transient transition stage.

[0092] Furthermore, in this embodiment of the application, the electrical steady-state values ​​of each steady-state stage, the initial value of the sudden change corresponding to the sudden change moment, and the sub-transient curves of the sub-transient transition stage are segmented and spliced ​​together according to the time sequence to generate a complete fault transient curve of the new energy power station.

[0093] The phased calculation method for transient curves of new energy power station faults proposed in this application divides the fault process of a new energy power station into a steady-state stage, an instantaneous change, and a sub-transient transition stage. The steady-state stage is further subdivided into a pre-steady-state stage, a fault quasi-steady-state stage, and a post-recovery steady-state stage. The corresponding steady-state values, initial values ​​of the sudden change, and sub-transient curves are solved hierarchically and then integrated to generate a complete fault transient curve. This method can adapt differentiated calculation logic based on the dominant electrical laws at different fault times, significantly reducing the calculation time for a single fault scenario. When facing the batch evaluation needs of multiple fault conditions and multiple sets of equipment control parameters, it can also significantly reduce the computational overhead caused by repeated calculations. The obtained fault transient curves can be output in seconds or even milliseconds, directly adapting to the real-time calculation needs of online optimization control of new energy power stations, providing reliable and rapid evaluation support for online control decisions. Therefore, it solves the problem that related technologies require the establishment of detailed models of equipment within the power station, resulting in limited computational efficiency and difficulty in adapting to online optimization control of new energy power stations.

[0094] Next, referring to the accompanying drawings, a phased calculation device for transient fault curves of new energy power stations proposed according to embodiments of this application is described.

[0095] Figure 8 This is a block diagram of a phased calculation device for transient curves of new energy power station faults provided in an embodiment of this application.

[0096] like Figure 8 As shown, the phased calculation device 80 for the fault transient curve of the new energy power station includes: a division module 100, a calculation module 200, and a generation module 300.

[0097] The partitioning module 100 is used to divide the fault process of the new energy power station into a steady-state stage, a sudden change moment and a sub-transient transition stage, and to further divide the steady-state stage into a pre-steady-state stage, a fault quasi-steady-state stage and a post-recovery steady-state stage.

[0098] The calculation module 200 is used to calculate the steady-state value in the steady-state stage, calculate the initial value of the sudden change at the moment of sudden change, and calculate the sub-transient curve in the sub-transient transition stage.

[0099] The generation module 300 is used to generate fault transient curves for new energy power plants based on steady-state values, initial values ​​of sudden changes, and sub-transient curves.

[0100] Optionally, in one embodiment of this application, it further includes: a first establishment module and a second establishment module.

[0101] The first module is used to establish the main circuit topology of the new energy power station.

[0102] The second module is used to establish the equipment equations, bus current equations, and bus line equations of the new energy power station in order to determine the steady-state equation set of the new energy power station.

[0103] Optionally, in one embodiment of this application, the calculation module 200 includes: an acquisition unit and a first calculation unit.

[0104] The acquisition unit is used to acquire the line parameters and control parameters of the new energy power station, and to acquire the grid parameters of the external power grid.

[0105] The first calculation unit is used to calculate the steady-state values ​​of electrical quantities based on line parameters, control parameters, power grid parameters, and equipment equations, so as to determine the steady-state values ​​in the steady-state stage.

[0106] Optionally, in one embodiment of this application, the calculation module 200 includes: a second calculation unit, a third calculation unit, and a first determination unit.

[0107] The second calculation unit is used to calculate the initial value of the sudden change in bus voltage based on power grid parameters and bus line equations.

[0108] The third calculation unit is used to calculate the initial value of the sudden change in the terminal voltage of the equipment based on the initial value of the sudden change in the bus voltage and the equipment equation.

[0109] The first determining unit is used to determine the initial value of the sudden change at the moment of the sudden change based on the initial value of the sudden change in bus voltage and the initial value of the sudden change in equipment terminal voltage.

[0110] Optionally, in one embodiment of this application, the calculation module 200 includes: a first generation unit, a second calculation unit, and a second determination unit.

[0111] The first generation unit is used to generate equipment sub-transient curves based on the control characteristics of the equipment in the new energy power station.

[0112] The second calculation unit is used to deduce the equipment equation, bus current equation, and bus line equation in a directional manner based on the equipment sub-transient curve, so as to deduce the electrical quantity curve from the equipment to the bus.

[0113] The second determining unit is used to determine the sub-transient curve of the sub-transient transition stage based on the electrical quantity curve.

[0114] It should be noted that the explanation of the aforementioned embodiment of the method for calculating the staged transient curve of faults in new energy power stations also applies to the device for calculating the staged transient curve of faults in new energy power stations in this embodiment, and will not be repeated here.

[0115] The phased calculation device for transient curves of new energy power station faults proposed in this application divides the fault process of a new energy power station into a steady-state stage, an instantaneous change, and a sub-transient transition stage. The steady-state stage is further subdivided into a pre-steady-state stage, a fault quasi-steady-state stage, and a post-recovery steady-state stage. After solving the corresponding steady-state values, initial values ​​of the sudden change, and sub-transient curves hierarchically, the device integrates them to generate a complete fault transient curve. It can adapt differentiated calculation logic based on the dominant electrical laws at different fault times, significantly reducing the calculation time for a single fault scenario. When facing the batch evaluation needs of multiple fault conditions and multiple sets of equipment control parameters, it can also significantly reduce the computational overhead caused by repeated calculations. The obtained fault transient curves can be output in seconds or even milliseconds, directly adapting to the real-time calculation needs of online optimization control of new energy power stations, providing reliable and rapid evaluation support for online control decisions. Therefore, it solves the problem that related technologies require the establishment of detailed models of equipment within the power station, resulting in limited computational efficiency and difficulty in adapting to online optimization control of new energy power stations.

[0116] Figure 9 This is a schematic diagram of the structure of an electronic device provided according to an embodiment of this application. The electronic device may include: The memory 901, the processor 902, and the computer program stored on the memory 901 and capable of running on the processor 902.

[0117] When the processor 902 executes the program, it implements the phased calculation method for the transient curve of faults in new energy power stations provided in the above embodiments.

[0118] Furthermore, electronic devices also include: Communication interface 903 is used for communication between memory 901 and processor 902.

[0119] The memory 901 is used to store computer programs that can run on the processor 902.

[0120] The memory 901 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0121] If the memory 901, processor 902, and communication interface 903 are implemented independently, then the communication interface 903, memory 901, and processor 902 can be interconnected via a bus to complete communication between them. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of representation, Figure 9 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0122] Optionally, in a specific implementation, if the memory 901, processor 902, and communication interface 903 are integrated on a single chip, then the memory 901, processor 902, and communication interface 903 can communicate with each other through an internal interface.

[0123] The processor 902 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application.

[0124] This application also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the above-described method for phased calculation of transient curves of faults in new energy power stations.

[0125] This application also provides a computer program product, including a computer program that, when executed, implements the above-mentioned method for phased calculation of transient curves of faults in new energy power stations.

[0126] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0127] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0128] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or N executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0129] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0130] It should be understood that the various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, it can be implemented using any one or more of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0131] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0132] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0133] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. A method for phased calculation of transient curves of faults in new energy power stations, characterized in that, Includes the following steps: The fault process of the new energy power station is divided into a steady-state stage, a sudden change moment and a sub-transient transition stage. The steady-state stage is further divided into a pre-steady-state stage, a fault quasi-steady-state stage and a post-recovery steady-state stage. Calculate the steady-state value of the steady-state stage, calculate the initial value of the sudden change at the instant of the sudden change, and calculate the sub-transient curve of the sub-transient transition stage; Based on the steady-state value, the initial value of the mutation, and the sub-transient curve, the fault transient curve of the new energy power station is generated.

2. The method according to claim 1, characterized in that, Before dividing the fault process of the new energy power station into the steady-state stage, the instantaneous change stage, and the sub-transient transition stage, it also includes: Establish the main circuit topology of the aforementioned new energy power station; Establish the equipment equations, bus current equations, and bus line equations of the new energy power station to determine the steady-state equation set of the new energy power station.

3. The method according to claim 2, characterized in that, The calculation of the steady-state value in the steady-state phase includes: Obtain the line parameters and control parameters of the new energy power station, and obtain the grid parameters of the external power grid; Based on the line parameters, the control parameters, the power grid parameters, and the equipment equations, the steady-state values ​​of the electrical quantities are calculated to determine the steady-state values ​​of the steady-state phase.

4. The method according to claim 3, characterized in that, The calculation of the initial value of the mutation at the instant of the mutation includes: Based on the power grid parameters and the bus line equation, calculate the initial value of the sudden change in bus voltage; Based on the initial value of the sudden change in the bus voltage and the equipment equation, calculate the initial value of the sudden change in the equipment terminal voltage; The initial value of the sudden change at the moment of the sudden change is determined based on the initial value of the sudden change in the bus voltage and the initial value of the sudden change in the equipment terminal voltage.

5. The method according to claim 4, characterized in that, The calculation of the sub-transient curve of the sub-transient transition phase includes: Based on the control characteristics of the equipment in the new energy power station, sub-transient curves of the equipment are generated; Based on the equipment sub-transient curve, the equipment equation, the bus current equation, and the bus line equation are recursively derived in a directional manner to derive the electrical quantity curve from the equipment to the bus. Based on the electrical quantity curve, the sub-transient curve of the sub-transient transition stage is determined.

6. A phased calculation device for transient curves of faults in new energy power stations, characterized in that, include: The partitioning module is used to divide the fault process of the new energy power station into a steady-state stage, a sudden change moment and a sub-transient transition stage, and further divide the steady-state stage into a pre-steady-state stage, a fault quasi-steady-state stage and a post-recovery steady-state stage. The calculation module is used to calculate the steady-state value of the steady-state stage, calculate the initial value of the sudden change at the instant of the sudden change, and calculate the sub-transient curve of the sub-transient transition stage. The generation module is used to generate the fault transient curve of the new energy power station based on the steady-state value, the initial value of the mutation, and the sub-transient curve.

7. The apparatus according to claim 6, characterized in that, Also includes: The first establishment module is used to establish the main circuit topology of the new energy power station; The second module is used to establish the equipment equations, bus current equations, and bus line equations of the new energy power station in order to determine the steady-state equation set of the new energy power station.

8. An electronic device, characterized in that, include: The system includes a memory, a processor, and a computer program stored in the memory and capable of running on the processor, wherein the processor executes the program to implement the phased calculation method for transient fault curves of new energy power stations as described in any one of claims 1-5.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to implement the phased calculation method for the fault transient curve of the new energy power station as described in any one of claims 1-5.

10. A computer program product, comprising a computer program, characterized in that, The computer program is executed to implement the phased calculation method for the transient curve of faults in new energy power stations as described in any one of claims 1-5.

Images