An active power support control method and system based on cooperation of a fan and a synchronous machine

Abstract

The application belongs to the related technical field, and proposes an active support control method and system based on fan and synchronous machine cooperation. When it is detected that the system frequency exceeds the frequency modulation dead zone, the deviation of the real-time frequency and the target frequency is solved step by step. The total power adjustment amount demand of the system in the step and the frequency modulation power change amount of the synchronous machine are calculated according to the deviation of the real-time frequency and the target frequency solved step by step. The frequency modulation power change amount of the fan in the step is obtained according to the total power adjustment amount demand of the system in the step and the frequency modulation power change amount of the synchronous machine, and then the support power that the fan should provide in the step is obtained. The application converts the traditional global control problem into an energy distribution problem in a short time step through discrete control, and gradually cooperates the fan and the synchronous machine group output to jointly support the power grid frequency to be stable near the target frequency curve.

Description

Technical Field

[0001] This invention belongs to the relevant technical field, and in particular relates to a method and system for active power support control based on the coordination of wind turbines and synchronous machines. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] With the increasing penetration rate of new energy units such as wind turbines, new power systems are facing challenges such as reduced inertia and increased difficulty in frequency stability control. Traditional active frequency support strategies for wind turbines are mainly designed by simulating the inertia and frequency regulation characteristics of synchronous generators, such as droop control and virtual inertial control. However, this approach of simulating synchronous machines has shortcomings: (1) The energy that a single wind turbine can provide is limited in a short time, and when it is removed from frequency regulation, it is prone to frequency drop problem; (2) The control effect is greatly affected by the parameters. Fixed control parameters are difficult to meet the needs of different operating scenarios, while so-called adaptive parameter adjustment faces problems such as complex control and difficulty in implementation. (3) The idea of ​​using a simulated synchronous machine as the target limits the flexibility of wind turbine control to a certain extent and does not fully utilize the flexibility and speed of power electronic converter control.

[0004] Unlike the approach of analog synchronous machines mentioned above, some current research focuses on improving the frequency stability of power systems, deriving frequency response curves that are beneficial for raising the system's minimum frequency and achieving optimal global frequency during the primary frequency regulation phase. Correspondingly, control strategies aimed at achieving these target frequency curves have been proposed, but most are still in transfer function form, making it difficult to effectively cope with changes in external natural conditions. Furthermore, they require the assumption that the wind turbine's frequency regulation capability is sufficiently large, which limits the practical application and promotion of these strategies. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, the present invention provides a power support control method and system based on the coordination of wind turbines and synchronous generators, which gradually increases the output of wind turbines and synchronous generators, can better cope with the target frequency changes caused by external conditions, and can achieve dynamic tracking effect.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a power support control method based on the coordinated operation of wind turbines and synchronous machines, comprising: Detect whether the frequency deviation of the detection system is within the frequency modulation dead zone; When the system frequency is detected to exceed the frequency modulation dead zone, the deviation between the real-time frequency and the target frequency is calculated step by step by step. The total power regulation requirement of the system within each control step is calculated based on the deviation between the real-time frequency and the target frequency obtained by solving for each control step, as well as the change in frequency modulation power of the synchronous machine. Based on the total power regulation requirement of the system within the step length and the change in frequency regulation power of the synchronous machine, the change in frequency regulation power of the fan within the step length is obtained, and then the support power that the fan should provide within the step length is obtained.

[0007] Secondly, the present invention provides a power support control system based on the coordination of wind turbines and synchronous machines, comprising: The judgment module is configured to detect whether the system frequency deviation is within the frequency modulation dead zone; The solution module is configured to: when the system frequency is detected to exceed the frequency modulation dead zone, control the step size one by one to solve the deviation between the real-time frequency and the target frequency; The calculation module is configured to: calculate the total power regulation requirement of the system within each control step and the change in the frequency modulation power of the synchronous machine based on the deviation between the real-time frequency and the target frequency obtained by solving for each control step. The active power support module is configured to: obtain the change in the frequency regulation power of the fan within the step length based on the total power regulation requirement of the system within the step length and the change in the frequency regulation power of the synchronous machine, and then obtain the support power that the fan should provide within the step length.

[0008] Thirdly, the present invention provides an electronic device including a memory and a processor, and computer instructions stored in the memory and running on the processor, wherein the computer instructions, when executed by the processor, perform the method described in the first aspect.

[0009] Fourthly, the present invention provides a computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the method described in the first aspect.

[0010] Fifthly, the present invention provides a computer program product, including a computer program that, when executed by a processor, implements the method described in the first aspect.

[0011] The above one or more technical solutions have the following beneficial effects: In this invention, when the system frequency is detected to exceed the frequency regulation dead zone, the deviation between the real-time frequency and the target frequency is calculated step by step. Based on the deviation between the real-time frequency and the target frequency calculated step by step, the total power regulation requirement of the system within the step and the change in synchronous machine frequency regulation power are calculated. Based on the total power regulation requirement of the system within the step and the change in synchronous machine frequency regulation power, the change in wind turbine frequency regulation power within the step is obtained, and thus the supporting power that the wind turbine should provide within the step is obtained. This invention transforms the traditional global control problem into a short-time step energy allocation problem through discrete control, gradually coordinating the output of wind turbines and synchronous units to jointly support the grid frequency to stabilize near the target frequency curve. With the increasing wind power penetration rate, this is of great significance for improving the active support effect of wind turbines and solving the problem of power system frequency stability.

[0012] In this invention, based on the target frequency at the end of the control step and the measured frequency at the beginning, the approximate output of the synchronous machine and the supporting power of the fan are coordinated to stabilize the actual frequency near the target frequency curve. The proposed strategy can better cope with the target frequency changes caused by external conditions and can achieve dynamic tracking effect.

[0013] In this invention, simulation experiments show that even when there are large errors in the system's inertial time constant and damping coefficient, the proposed strategy can achieve the frequency control target under various inaccurate parameter acquisition conditions, and the difference is very small compared with when the parameters are accurately acquired. The proposed strategy has good robustness to parameter acquisition errors, which is conducive to the practical application of the strategy.

[0014] In this invention, when the communication delay increases, the system frequency fluctuation will increase, but the system frequency can still converge to the vicinity of the target frequency relatively quickly, especially in the latter half of the frequency tracking control, where there is basically no fluctuation. This shows that the strategy proposed in this invention has a certain robustness to communication delay.

[0015] Advantages of additional aspects of the invention 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 the invention. Attached Figure Description

[0016] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0017] Figure 1 This is the frequency response model of a system containing wind power in this embodiment of the invention; Figure 2 This is a schematic diagram of the optimal frequency response curve in an embodiment of the present invention; Figure 3 This is a schematic diagram of single-step control in an embodiment of the present invention; Figure 4 This is a schematic diagram of the simulation verification model in an embodiment of the present invention; Figure 5 This is a diagram illustrating the tracking control effect of different target frequency curves in an embodiment of the present invention; Figure 6 This is a dynamic tracking effect diagram when the target frequency changes continuously in an embodiment of the present invention; Figure 7 This is a diagram illustrating the control effect when there are errors in parameter acquisition in an embodiment of the present invention. Figure 8 This is a schematic diagram illustrating the impact of communication delay on control performance in an embodiment of the present invention; Figure 9 This is a flowchart of the active power support control method based on the coordination of wind turbine and synchronous machine in an embodiment of the present invention. Detailed Implementation

[0018] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0019] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations of the present invention.

[0020] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0021] Example 1 This embodiment discloses a power support control method based on the coordination of wind turbines and synchronous machines, including: Detect whether the frequency deviation of the detection system is within the frequency modulation dead zone; When the system frequency is detected to exceed the frequency modulation dead zone, the deviation between the real-time frequency and the target frequency is calculated step by step by step. The total power regulation requirement of the system within each control step is calculated based on the deviation between the real-time frequency and the target frequency obtained by solving for each control step, as well as the change in frequency modulation power of the synchronous machine. Based on the total power regulation requirement of the system within the step length and the change in frequency regulation power of the synchronous machine, the change in frequency regulation power of the fan within the step length is obtained, and then the support power that the fan should provide within the step length is obtained.

[0022] In this embodiment, given the acquisition of the target frequency curve, the system collects local frequency information and coordinates the output of the synchronous machine and the fan within the discrete control step size, enabling the actual frequency curve of the system to track the target frequency curve more quickly.

[0023] Ignoring spatial differences in frequency distribution, the system swing equation considering wind turbine support is: (1) In the formula, Δ f(t) This refers to the deviation of the system's real-time frequency from its rated frequency. This is the adjustment amount of the mechanical power of the synchronous machine; This refers to the active support power of the wind turbine; denoted as the load power change; H and D are the system inertial time constant and damping coefficient, respectively.

[0024] Accordingly, the classical system frequency response model used in this embodiment can be expressed as follows: Figure 1 .

[0025]

[0026]

[0027]

[0028] in, K m For the mechanical power gain of the synchronizing machine; F H The power ratio of the high-pressure cylinder; R This is the governor droop coefficient; T R is the reheat time constant.

[0029] The system frequency response model simplifies the boiler-steam process, retaining only the most influential inertial time constant and reheat time constant. Due to its simple and accurate expression, it has been widely used and is suitable for frequency analysis of reheat steam turbine generators.

[0030] The target frequency curve represents the system inertia and ideal frequency trajectory during the first frequency regulation period, calculated based on a specific objective and considering the system's frequency regulation capability and requirements after a frequency disturbance event. For example, with the objective of raising the system's lowest frequency, and assuming sufficient system frequency regulation capability, research has indicated that the target frequency curve for the optimal system inertia and global frequency during the first frequency regulation phase should exhibit a "rapid decline-maintaining level" characteristic, meaning the lowest frequency should numerically equal to the frequency at which the first frequency regulation is fully responded. When the control objective changes or the frequency regulation capability is insufficient, the target frequency trajectory will differ. However, under the premise of a reasonably formulated control strategy, its trajectory should lie between the frequency trajectory when the wind turbine is unsupported and the aforementioned optimal frequency trajectory. Without loss of generality, this embodiment will use the optimal frequency response curve as an example to illustrate the target frequency dynamic tracking control strategy for wind turbine and synchronous machine coordination.

[0031] Theoretically, the optimal target frequency response curve should be a piecewise function with a "rapid decrease-level maintenance" characteristic. However, the above frequency curve has abrupt frequency change inflection points at the segmentation points. The sudden and sharp change in the rate of frequency change can easily lead to an increase in the risk of shaft torsional vibration and malfunction of protection devices. Therefore, it is necessary to find a smooth, approximately optimal frequency response curve while retaining the key characteristics of the optimal target frequency response curve.

[0032] This embodiment uses a first-order inertial element to approximate the optimal frequency response curve, as shown in Figure 2.

[0033] In Figure 2, the red dashed line represents the approximately optimal frequency response curve, expressed as follows: (2) In the formula, A This represents the steady-state gain of the first-order inertial response. The time constant determines the response speed; This is the end time of one frequency modulation. t 0 represents the time when the frequency disturbance event occurred; f N The rated frequency is 50Hz in this embodiment.

[0034] The frequency discrete dynamic tracking strategy proposed in this embodiment is shown in Figure 3. After detecting that the frequency exceeds the frequency modulation dead zone, the controller will control the step size one by one to solve for the real-time frequency of the system. f A With target frequency f B The deviation is calculated, and the total power regulation requirement of the system and the change in frequency regulation power of the synchronous machine are calculated respectively to obtain the frequency regulation power command of the wind turbine within the control step. When the time step reaches the next step, the "grid information input - frequency regulation power allocation - control command output" process is repeated to finally stabilize the real-time frequency near the target rate curve.

[0035] It should be noted that the above control process actually includes a coordinated control mechanism for the wind turbine and the synchronous machine. That is, based on the target frequency guidance and real-time frequency measurement, the total energy required to support various heterogeneous power sources is first calculated; then, based on the measured frequency change in the previous time step, the change in the synchronous machine support within the previous time step can be calculated. Since the synchronous machine operates much slower than the wind turbine, the calculated change in the synchronous machine support in the previous time step is approximately taken as the change in the synchronous machine support in this time step; finally, the two are subtracted to obtain the command for the change in the wind turbine support in this time step, which is then sent to each wind turbine controller for execution.

[0036] Combination Figure 1 and Figure 3 In order to change the frequency from the real-time frequency f AControlled to target frequency f B The total frequency modulation power requirement within the step size is calculated as follows: (3) In the formula, Δ P tot,A→B This indicates that the frequency will be changed from the real-time frequency within a step size. f A Controlled to target frequency f B The required change in total regulating power; and These represent the total adjustment power at the start and end times of the step size, respectively. This represents the expected change in frequency deviation within the step size, where... The measured frequency deviation at the start of the step size. denoted as , where is the target frequency deviation at the end of the step; A is the steady-state gain of the first-order inertial response; H and D are the system inertial time constant and damping coefficient, respectively.

[0037] It should be noted that the equivalent inertia time in the above calculations can be obtained by calculating information such as the power capacity of the wind turbine and synchronous machine. The equivalent damping of the system is mainly provided by the load and can be calculated based on the actual measurement data of the power grid.

[0038] The derivation of the calculation of the equivalent inertial time constant is as follows: Inertial time constant for power systems H To characterize system inertia, the ratio of the rotor kinetic energy of the synchronous generator at synchronous angular velocity to the system's rated capacity is typically chosen. (4) In the formula, J i Characterizing generator i Moment of inertia; p i For generator i The extreme logarithm; S N,i For generator i Rated capacity; and These are mechanical angular velocity and synchronous electric angular velocity, respectively. n This represents the total number of generators.

[0039] After wind power is connected to the grid, because the turbine's rotation frequency is decoupled from the system frequency, it cannot directly sense frequency changes and thus provide inertial support like a synchronous machine. Therefore, the inertial time constant of the power system containing wind power is calculated as follows: (5) In the formula,S W,j For wind turbine j Rated capacity; m This represents the total number of wind turbines. S N,i For generator i Rated capacity; Synchronous electric angular velocity; n This represents the total number of generators. J i Characterizing generator i The moment of inertia.

[0040] As can be seen, the equivalent inertial time constant of the system decreases after the wind turbines are connected to the grid. When the inertial time constant of the synchronous machine is known, combining equations (4) and (5), the calculation method for the inertial time constant of a power system containing wind power can be obtained as follows: (6) The value of the equivalent damping coefficient of the system is mainly affected by the magnitude of the load damping. The calculation method is as follows: (7) In the formula, Δ P load Δ is the change in system load following a frequency change; D is the system damping coefficient; Δ f This represents the deviation of the system's real-time frequency from its rated frequency. Therefore, after a frequency disturbance event, the system's equivalent damping coefficient can be obtained based on measurement data.

[0041] The mechanical power of the synchronous machine is adjusted in real time according to the frequency deviation. However, due to the lag in response from components such as boiler heat storage, and because its response speed is much slower than that of a fan based on a power electronic converter, this strategy approximates the change in the synchronous machine's frequency modulation power in the current step by using the change in mechanical power from the previous step.

[0042] (8) In the formula, Δ P m,A→B To change the frequency within the step size f A Control to f B The corresponding change in the mechanical power of the synchronizing machine at that time; Δ P m,A and Δ P m,B These represent the mechanical power increments at the start and end times of the step, respectively; Δ P m,c This is the amount of mechanical power support provided by the synchronizing machine at the long start time of the previous step; This represents the frequency deviation at the previous long start time. K m For the mechanical power gain of the synchronizing machine; F H The power ratio of the high-pressure cylinder; R This is the governor droop coefficient; T R is the reheat time constant.

[0043] Clearly, the calculation method above ensures that the controller only needs to collect frequency information to complete the approximate calculation of the synchronous machine's mechanical power. However, the introduction of the transfer function inevitably leads to an increase in the required parameters. It should be noted that the parameters in the transfer function above are all basic parameters of the synchronous machine, which are generally considered to be practically obtainable.

[0044] Calculation of frequency regulation power command for wind turbines: In addition to equation (3), the total frequency modulation power requirement can also be expressed as the following equation: (9) in, and These represent the total regulation power at the start and end times of the step size, respectively; Δ P m,A and Δ P m,B These represent the mechanical power increments at the start and end times of the step, respectively.

[0045] It can be seen that the total frequency regulation demand is provided jointly by the wind turbine and the synchronous machine. Therefore, the change in wind turbine frequency regulation power... The calculation is as follows: (10) in, The initial step size represents the fan support power. Δ represents the fan support power at the end of the step length; P tot,A→B This indicates that the frequency will change from within the step size. f A Control to f B The required change in total regulating power; Δ P m,A→B To change the frequency within the step size f A Control to f B The corresponding change in the mechanical power of the synchronous machine; H is the inertial time constant of the power system; D is the system damping coefficient; Δ f This refers to the deviation of the system's real-time frequency from its rated frequency. Km For the mechanical power gain of the synchronizing machine; F H The power ratio of the high-pressure cylinder; R This is the governor droop coefficient; T R is the reheat time constant.

[0046] It can be seen that the final derived formula for calculating the change in wind turbine support power only requires frequency information to be collected from the power grid, which facilitates its deployment in the power coordination control system of wind farms for practical application. On the other hand, the above formula requires certain system parameter information, the specific acquisition method of which has been described above. The robustness of the proposed strategy in dealing with parameter acquisition errors will also be demonstrated through simulation later.

[0047] It should be noted that sudden changes in load power can lead to sudden changes in frequency, which in turn affects the target frequency determination process. The execution of subsequent control strategies is based on the target frequency curve affected by load changes. Therefore, the total frequency regulation power in equation (9) does not need to consider the impact of load.

[0048] The calculation results of (10) are added to the fan support power at the initial moment of the step size to obtain the support power that the fan should provide within that step size: (11) By solving the above steps of power grid information acquisition, frequency regulation power allocation, and control command output separately at each step, the supporting power of the wind turbine within each control step can be calculated in a rolling manner. When external conditions change, the target frequency generation module will automatically update the subsequent target frequency curve. After receiving the updated target frequency, the tracking control module will automatically coordinate the output of various heterogeneous power sources to achieve dynamic tracking control.

[0049] This embodiment transforms the traditional global control problem into a short-time-step energy allocation problem through discrete control, gradually coordinating the output of wind turbines and synchronous generators to jointly support the grid frequency stability near the target frequency curve. Given the increasing wind power penetration rate, this is of great significance for improving the active support effect of wind turbines and solving the power system frequency stability problem.

[0050] A simulation model was built in MATLAB / Simulink, using a real offshore wind power transmission system as a reference. A schematic diagram is shown below. Figure 4 As shown.

[0051] The flexible direct transmission line includes three wind farms with installed capacities of 400MW, 300MW, and 400MW respectively. The generated electricity from the wind farms is transmitted to the onshore converter station via ±400kV submarine DC cables. Other system parameters are shown in Table 1.

[0052] Table 1 Simulation Model Parameters

[0053] Considering the need for active frequency support, the wind turbine reserves 10% of its active power as a backup. The following sections will verify the proposed strategy's dynamic tracking control effect on the target frequency, its dynamic tracking effect when wind resource fluctuations cause changes in the target frequency, and its robustness to system parameter acquisition errors and communication delays.

[0054] First, a load surge of 1000MW is set at t=10.0s. The target frequency curve is then derived based on the wind turbine's frequency regulation capability. The simulation results after implementing this strategy are as follows: Figure 5 .

[0055] It can be seen that, Figure 5 Two target frequency curves were preset for verification. When the wind turbine's active support capability is weak, the main purpose of the wind turbine's active support is to control the frequency within a safe range. Figure 5 The corresponding frequency deviation is no greater than 0.2Hz, corresponding to target frequency curve 1. When the wind turbine has strong active capability, it can support the system to achieve a smaller frequency deviation. Figure 5 The corresponding target frequency curve is shown in Figure 2. It can be seen that the proposed strategy, by coordinating the power support of the synchronous machine and the wind turbine, can quickly stabilize the system frequency to near the target frequency, demonstrating the effectiveness of the proposed strategy in frequency tracking control.

[0056] When changes in external wind resources cause continuous changes in the active support capacity of wind turbines, the target frequency curve may change continuously. This requires the proposed strategy to have the ability to track the dynamically changing target frequency. Taking a sudden load increase of 1000MW at t=10.0s as an example, the target frequency is set to change multiple times at t=10.0s, 13.0s, 15.0s, and 17.0s. The specific changes corresponding to equation (2) are shown in Table 2.

[0057] Table 2 Target Frequency Continuous Variation Data

[0058] Frequency dynamic tracking control effect when the target frequency changes continuously, such as Figure 6 As shown, when changes in external conditions cause continuous changes in the target frequency, the proposed strategy can coordinate the approximate output of the synchronous machine and the supporting power of the wind turbine based on the target frequency at the end of the control step and the measured frequency at the beginning, so that the actual frequency is stabilized near the target frequency curve. This shows that the proposed strategy can better cope with changes in the target frequency caused by external conditions and can achieve dynamic tracking effect.

[0059] Furthermore, as shown in the aforementioned derivation, the effective execution of the proposed strategy depends to some extent on the system inertial time constant and damping coefficient. Compared to most existing control strategies, the strategy proposed in this embodiment does not have a large parameter requirement. However, in actual power grids, there may still be situations where the system inertial time constant H and the system damping coefficient D cannot be accurately obtained. Therefore, it is necessary to study the control effect of this strategy when the parameters H and D are not accurately obtained. Taking a sudden load increase of 1000MW at t=10.0s as an example, random combinations of the two parameters are generated within ±30% of the original given values. The simulation results are as follows. Figure 7 As can be seen, despite the large errors in setting the H and D parameters, the proposed strategy can still achieve the frequency control target even when the parameters are not accurately obtained, and the difference is very small compared to when the parameters are accurately obtained. This shows that the strategy proposed in this embodiment has good robustness to parameter acquisition errors, which is conducive to the practical application of the strategy.

[0060] When applying this strategy to an offshore wind power transmission system via flexible direct current transmission, it is necessary to transmit onshore frequency information to the sea. When using communication control to transmit information, communication delays are inevitable. Furthermore, with the development of offshore wind power, the distance of offshore wind farms from shore is gradually increasing; therefore, it is necessary to explore the impact of communication delays on the control effectiveness of this strategy. Literature review determined that the current communication delay range is 50-80ms. Taking a sudden load increase of 1000MW at t=10.0s as an example, the analysis was conducted, setting the controller's reception delay to the system frequency to 50ms, 100ms, and 150ms. Simulation results are as follows: Figure 8 As can be seen, when the communication delay increases, the system frequency fluctuation will increase, but the system frequency can still converge to the vicinity of the target frequency relatively quickly. Especially in the latter half of the frequency tracking control, there is basically no fluctuation, which shows that this strategy has a certain robustness to communication delay.

[0061] Example 2 The purpose of this embodiment is to provide a power support control system based on the coordination of wind turbines and synchronous machines, including: The judgment module is configured to detect whether the system frequency deviation is within the frequency modulation dead zone; The solution module is configured to: when the system frequency is detected to exceed the frequency modulation dead zone, control the step size one by one to solve the deviation between the real-time frequency and the target frequency; The calculation module is configured to: calculate the total power regulation requirement of the system within each control step and the change in the frequency modulation power of the synchronous machine based on the deviation between the real-time frequency and the target frequency obtained by solving for each control step. The active power support module is configured to: obtain the change in the frequency regulation power of the fan within the step length based on the total power regulation requirement of the system within the step length and the change in the frequency regulation power of the synchronous machine, and then obtain the support power that the fan should provide within the step length.

[0062] In further embodiments, the following is also provided: An electronic device includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor. When executed by the processor, the computer instructions perform the method described in Embodiment 1. For brevity, further details are omitted here.

[0063] It should be understood that in this embodiment, the processor can be a central processing unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor, etc.

[0064] Memory may include read-only memory and random access memory, and provides instructions and data to the processor. A portion of memory may also include non-volatile random access memory. For example, memory may also store information about the device type.

[0065] A computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the method described in Embodiment 1.

[0066] The method in Embodiment 1 can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor. The software modules can reside in readily available storage media in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory; the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method. To avoid repetition, a detailed description is not provided here.

[0067] A computer program product includes a computer program that, when executed by a processor, implements the method described in Embodiment 1.

[0068] The present invention also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as instructions included in program modules, which execute in a device on a target real or virtual processor to perform the processes / methods described above. Typically, program modules include routines, programs, libraries, objects, classes, components, data structures, etc., that perform specific tasks or implement specific abstract data types. In various embodiments, the functionality of program modules can be combined or divided among program modules as needed. The machine-executable instructions for the program modules can execute within a local or distributed device. In a distributed device, the program modules can reside in both local and remote storage media.

[0069] The computer program code used to implement the methods of the present invention may be written in one or more programming languages. This computer program code may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the computer or other programmable data processing device, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a computer, partially on a computer, as a stand-alone software package, partially on a computer and partially on a remote computer, or entirely on a remote computer or server.

[0070] In the context of this invention, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, and the like. Examples of signals may include electrical, optical, radio, sound, or other forms of propagation signals, such as carrier waves, infrared signals, etc.

[0071] Those skilled in the art will recognize that the units and algorithm steps described in conjunction with the embodiments herein can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0072] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for active power support control based on the coordinated operation of wind turbines and synchronous machines, characterized in that, include: Detect whether the frequency deviation of the detection system is within the frequency modulation dead zone; When the system frequency is detected to exceed the frequency modulation dead zone, the deviation between the real-time frequency and the target frequency is calculated step by step by step. The total power regulation requirement of the system within each control step is calculated based on the deviation between the real-time frequency and the target frequency obtained by solving for each control step, as well as the change in frequency modulation power of the synchronous machine. Based on the total power regulation requirement of the system within the step length and the change in frequency regulation power of the synchronous machine, the change in frequency regulation power of the fan within the step length is obtained, and then the support power that the fan should provide within the step length is obtained.

2. The active power support control method based on the coordinated operation of wind turbines and synchronous machines as described in claim 1, characterized in that, The total power regulation requirement of the system within each control step is calculated based on the deviation between the real-time frequency and the target frequency obtained from each control step. Specifically: ； Where, Δ P tot,A→B This indicates that the frequency will be changed from the real-time frequency within a step size. f A Controlled to target frequency f B The required change in total regulating power; and These represent the total adjustment power at the start and end times of the step size, respectively. The expected change in frequency deviation within the step size is represented by A, which is the steady-state gain of the first-order inertial response. H and D are the system inertial time constant and damping coefficient, respectively.

3. The active power support control method based on the coordinated operation of wind turbines and synchronous machines as described in claim 2, characterized in that, The system inertial time constant H is calculated as follows: ； in, It is the ratio of the rotor kinetic energy of the synchronous generator at the synchronous angular velocity to the rated capacity of the system; S N,i For generator i Rated capacity; S W,j For wind turbine j Rated capacity; m This represents the total number of wind turbines. n This represents the total number of generators.

4. The active power support control method based on the coordinated operation of wind turbines and synchronous machines as described in claim 2, characterized in that, The system damping coefficient is the ratio of the change in system load following a frequency change to the deviation of the system's real-time frequency from its rated frequency.

5. The active power support control method based on the coordinated operation of wind turbines and synchronous machines as described in claim 1, characterized in that, The change in frequency modulation power of the synchronous machine is calculated based on the deviation between the real-time frequency and the target frequency obtained by solving for each control step, specifically as follows: ； Where, Δ P m,A→B To change the frequency from the real-time frequency within a step size f A Controlled to target frequency f B The corresponding change in the mechanical power of the synchronizing machine at that time; Δ P m,A and Δ P m,B These represent the mechanical power increments at the start and end times of the step, respectively; Δ P m,c This is the amount of mechanical power support provided by the synchronizing machine at the long start time of the previous step; K m For the mechanical power gain of the synchronizing machine; F H The power ratio of the high-pressure cylinder; R This is the governor droop coefficient; T R is the reheat time constant.

6. The active power support control method based on the coordinated operation of wind turbines and synchronous machines as described in claim 1, characterized in that, The change in fan frequency regulation power within the step length is obtained based on the total power regulation requirement of the system within the step length and the change in synchronous machine frequency regulation power. Specifically: ； Where, Δ P tot,A→B This indicates that the frequency will be changed from the real-time frequency within a step size. f A Controlled to target frequency f B The required change in total regulating power; Δ P m,A→B To change the frequency within the step size f A Control to f B The corresponding change in the mechanical power of the synchronous machine; H is the inertial time constant of the power system; D is the system damping coefficient; Δ f This refers to the deviation of the system's real-time frequency from its rated frequency. K m For the mechanical power gain of the synchronizing machine; F H The power ratio of the high-pressure cylinder; R This is the governor droop coefficient; T R The reheat time constant; This represents the frequency deviation at the previous long start time.

7. The active power support control method based on the coordinated operation of wind turbines and synchronous machines as described in claim 1, characterized in that, The change in the frequency modulation power of the fan within the step length is accumulated and added to the fan support power at the initial moment of the step length to obtain the support power that the fan should provide within the corresponding step length.

8. A power support control system based on the coordinated operation of wind turbines and synchronous machines, characterized in that, include: The judgment module is configured to detect whether the system frequency deviation is within the frequency modulation dead zone; The solution module is configured to: when the system frequency is detected to exceed the frequency modulation dead zone, control the step size one by one to solve the deviation between the real-time frequency and the target frequency; The calculation module is configured to: calculate the total power regulation requirement of the system within each control step and the change in the frequency modulation power of the synchronous machine based on the deviation between the real-time frequency and the target frequency obtained by solving for each control step. The active power support module is configured to: obtain the change in the frequency regulation power of the fan within the step length based on the total power regulation requirement of the system within the step length and the change in the frequency regulation power of the synchronous machine, and then obtain the support power that the fan should provide within the step length.

9. An electronic device, characterized in that, It includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, perform the method according to any one of claims 1-6.

10. A computer-readable storage medium, characterized in that, Used to store computer instructions, which, when executed by a processor, perform the method described in any one of claims 1-6.

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