Wind turbine generator high voltage ride through control method, system, equipment and medium

Abstract

The invention discloses a wind turbine generator high voltage ride through control method, system and device and a medium, and relates to the technical field of wind power, and the method comprises the steps: collecting a three-phase voltage signal of a power grid in real time; generating a dynamic state factor based on the preprocessed three-phase voltage signal; generating a trend factor according to the change rate of the dynamic state factor in combination with a time sequence trend index; according to the trend factor, reactive current output is dynamically adjusted through a grid-side converter, and a reactive power instruction is generated; generating a theoretical active power value according to the trend factor and the reactive power instruction in combination with fan mechanical characteristic parameters; and dynamically adjusting the active power output of the wind turbine generator. According to the wind turbine generator high voltage ride through control method provided by the invention, the problems of response lag, insufficient adjustment precision and overlarge power fluctuation are solved, and the overshoot phenomenon in the power adjustment process is avoided; and through dynamic smooth adjustment, the power fluctuation is reduced, and the operation stability and the adjustment accuracy of the wind turbine generator during high voltage ride through are ensured.

Description

Technical Field

[0001] The present invention relates to the field of wind power technology, and in particular to a high voltage ride through control method, system, equipment and medium for a wind turbine generator set. Background Art

[0002] With the rapid development of wind power technology, the scale of wind farms continues to expand, and the operating performance of grid-connected wind turbines has an increasingly significant impact on the stability of the power grid. When wind turbines are connected to the grid, they must not only meet the requirements of power generation efficiency and operational safety, but also have the ability to adapt to abnormal grid conditions, especially high voltage ride-through capabilities. High voltage ride-through requires that wind turbines can maintain stable operation and provide reactive power support when the grid voltage rises to a certain range to ensure the stability of the grid system.

[0003] In the prior art, the high voltage ride-through control method of wind turbines is usually achieved by adjusting reactive power and active power. However, the traditional control method has the following shortcomings: on the one hand, the dynamic response lags, resulting in the inability of wind turbines to make timely adjustments when the grid voltage changes, which may cause unstable operation or even the risk of disconnection from the grid; on the other hand, the adjustment accuracy is insufficient, especially under complex grid conditions, the control logic of a single parameter is difficult to meet actual needs. In addition, the traditional method lacks comprehensive consideration of the mechanical characteristics of the wind turbine during the power adjustment process, which is prone to problems such as overshoot or excessive power fluctuations, thereby affecting the operating life of the wind turbine and the stability of the grid.

[0004] In order to meet the above challenges, wind turbine control strategies based on multiple parameters have been gradually proposed in recent years, such as the introduction of a comprehensive control method that introduces reactive current regulation and dynamic monitoring of grid voltage. However, these methods still face problems such as high engineering complexity and lack of real-time performance in practical applications, and it is difficult to fully meet the high requirements of modern power grids. Therefore, there is an urgent need for a high voltage ride-through control method that can integrate multiple grid state parameters and quickly and stably adjust the output power of wind turbines to improve the operating reliability and grid adaptability of wind turbines. Summary of the invention

[0005] In view of the above-mentioned problems, the present invention is proposed.

[0006] Therefore, the technical problem solved by the present invention is: the existing high voltage ride-through control method for wind turbines has problems such as response lag, insufficient regulation accuracy, excessive power fluctuation and incomplete characterization of the dynamic characteristics of the power grid, as well as how to optimize the dynamic response capability and regulation stability of the wind turbine in a complex power grid environment.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions: A high voltage ride through control method for a wind turbine generator system, comprising: Collect the three-phase voltage signal of the power grid in real time and pre-process the three-phase voltage signal; Based on the preprocessed three-phase voltage signal, the voltage fundamental component, the voltage fluctuation standard deviation, the grid frequency offset and the three-phase voltage imbalance are calculated to generate a dynamic state factor; According to the rate of change of the dynamic state factor, combined with the time series trend index, a trend factor is generated; According to the trend factor, dynamically adjusting reactive current output through the grid-side converter and generating reactive power instructions; Generate a theoretical active power value according to the trend factor and the reactive power command combined with the mechanical characteristic parameters of the wind turbine; The output power command of the wind turbine is generated based on the theoretical active power value, and the active power output of the wind turbine is dynamically adjusted.

[0008] As a preferred solution of the high voltage ride through control method for wind turbines described in the present invention, wherein: the preprocessing includes low pass filtering of the three-phase voltage signal; Perform phase-locked synchronization processing on the low-pass filtered signal; Perform mean removal and amplitude normalization on the synchronized signal; The normalized signal is subjected to sliding window outlier removal to obtain the preprocessed three-phase voltage signal.

[0009] As a preferred solution of the high voltage ride through control method for wind turbines described in the present invention, the dynamic state factor is expressed as: , , , , , in, Represents the fundamental component of the three-phase voltage, represents the sampling period, Represents the three-phase instantaneous voltage signal, represents the standard deviation of voltage fluctuation, represents the total number of sampling points, Indicates The sampled voltage value, Represents the average value of the voltage sampling value, Indicates the grid frequency offset, Indicates the real-time measured grid frequency. Indicates the rated frequency of the power grid, Indicates the unbalance of the three-phase voltage. Represents the instantaneous amplitude of the three-phase voltage, represents the gain factor, Represents the dynamic state factor.

[0010] As a preferred solution of the high voltage ride through control method for wind turbines described in the present invention, the trend factor is expressed as: , , , in, represents the trend factor, represents the rate of change of the dynamic state factor, represents the time series trend index, Represents the dynamic state factor of the current moment and the previous moment, represents the sampling time interval, represents the time series weight factor, Indicates The dynamic state factor at the moment, Indicates the length of the time series.

[0011] As a preferred solution of the high voltage ride through control method for wind turbines described in the present invention, the reactive power instruction is expressed as: , , in, Represents reactive current, Indicates reactive power command, represents the trend factor, Indicates the trigger threshold of the trend factor, Represents the gain factor of reactive current, Indicates the bus voltage.

[0012] As a preferred solution of the high voltage ride through control method for wind turbines described in the present invention, the theoretical active power value is expressed as: , , , , in, Indicates the theoretical active power value, Indicates the rated active power of the fan. represents the trend factor, represents the maximum value of the trend factor, Indicates the dynamic reactive power change rate, Indicates the rated value of reactive power, Indicates the reactive power at the current and previous moment, Indicates the fan speed deviation. Indicates the rated speed of the fan. Indicates the maximum speed deviation. Indicates the real-time wind speed. Indicates the rated wind speed of the fan. Represents the wind speed impact factor.

[0013] As a preferred solution of the high voltage ride through control method for wind turbines described in the present invention, the dynamic adjustment of the active power output of the wind turbines includes adjusting the theoretical active power value Perform limiting processing; set the rated output power upper limit of the wind turbine and minimum operating power As the power limit boundary; when When the output power is adjusted to ;when When the output power is adjusted to ;when ≤ ≤ When unchanged; the power value after limiting is ; Get the current operating power of the fan And the power value after limiting The difference between them is expressed as, ; According to the maximum power change rate Set the adjustment range when > When the power is adjusted to ;when < When the power is adjusted to ;when ≤ ≤ When The result after power adjustment is ; Based on the power adjustment results Generate output power command; send power adjustment result and power adjustment rate to wind turbine control system; adjust blade angle, speed and converter operation status through wind turbine control system; the adjusted wind turbine output power is ; The power adjustment rate is expressed as, .

[0014] Another object of the present invention is to provide a high voltage ride-through control system for a wind turbine, which can solve the problems in the prior art that single parameter control cannot adapt to the rapid changes in grid voltage in a timely manner, the lack of rate limit in the power adjustment process leads to excessive regulation fluctuations, and the control errors caused by insufficient signal preprocessing accuracy by constructing a high voltage ride-through control system for a wind turbine.

[0015] In order to solve the above technical problems, the present invention provides the following technical solutions: a high voltage ride-through control system for a wind turbine, comprising: a data acquisition module, a state analysis module, a trend analysis module, a reactive power regulation module, an active power calculation module and a power adjustment module; the data acquisition module is used to collect the three-phase voltage signal of the power grid in real time and pre-process the three-phase voltage signal; the state analysis module is used to calculate the voltage fundamental component, the voltage fluctuation standard deviation, the power grid frequency offset and the three-phase voltage imbalance based on the pre-processed three-phase voltage signal to generate a dynamic state factor; the trend analysis module is used to generate a trend factor according to the change rate of the dynamic state factor in combination with a time series trend index; the reactive power regulation module is used to dynamically adjust the reactive current output through the grid-side converter according to the trend factor and generate a reactive power instruction; the active power calculation module is used to generate a theoretical active power value according to the trend factor and the reactive power instruction in combination with the mechanical characteristic parameters of the wind turbine; the power adjustment module is used to generate an output power instruction of the wind turbine based on the theoretical active power value and dynamically adjust the active power output of the wind turbine.

[0016] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the high voltage ride through control method of a wind turbine generator set when executing the computer program.

[0017] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the high voltage ride-through control method for a wind turbine generator set as described above.

[0018] Beneficial effects of the present invention: The high voltage ride-through control method for wind turbines provided by the present invention solves the problems of response lag, insufficient regulation accuracy and excessive power fluctuation in the prior art by generating dynamic state factors and trend factors. The dynamic state factor is generated based on the calculation results of the grid voltage fundamental component, voltage fluctuation standard deviation, grid frequency offset and three-phase voltage imbalance, and comprehensively characterizes the dynamic changes of the grid; the trend factor combines the change rate of the dynamic state factor and the time series trend index, and provides a quantitative basis for the regulation of reactive power and active power by reflecting the dynamic trend of the grid. In the process of power regulation, the present invention avoids overshoot in the process of power regulation through limiting protection and power change rate constraints; through dynamic smoothing adjustment, power fluctuations are reduced, ensuring the operating stability and regulation accuracy of wind turbines during high voltage ride-through, and meeting the high requirements of modern power grids. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0020] Figure 1 An overall flow chart of a high voltage ride through control method for a wind turbine generator system provided by an embodiment of the present invention.

[0021] Figure 2 This is an overall structural diagram of a wind turbine high voltage ride through control system provided in accordance with a second embodiment of the present invention. DETAILED DESCRIPTION

[0022] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0023] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0024] Example 1

[0025] Reference Figure 1, which is an embodiment of the present invention, provides a high voltage ride through control method for a wind turbine generator set, comprising: S1 collects the three-phase voltage signals of the power grid in real time and pre-processes the three-phase voltage signals; S2 calculates the voltage fundamental component, voltage fluctuation standard deviation, grid frequency offset and three-phase voltage imbalance based on the preprocessed three-phase voltage signal to generate a dynamic state factor; S3 generates trend factors based on the rate of change of dynamic state factors and the time series trend index; S4 dynamically adjusts reactive current output through the grid-side converter according to the trend factor and generates reactive power instructions; S5 generates a theoretical active power value according to the trend factor and the reactive power command combined with the mechanical characteristic parameters of the wind turbine; S6 generates an output power instruction of the wind turbine generator set based on the theoretical active power value, and dynamically adjusts the active power output of the wind turbine generator set.

[0026] The preprocessing includes low-pass filtering the three-phase voltage signal; Perform phase-locked synchronization processing on the low-pass filtered signal; Perform mean removal and amplitude normalization on the synchronized signal; The normalized signal is subjected to sliding window outlier removal to obtain the preprocessed three-phase voltage signal.

[0027] The three-phase voltage signal of the power grid is collected in real time through voltage sensors and sampling equipment, and the instantaneous value of each phase voltage is recorded respectively. The sampling frequency of the sampling equipment should meet the Nyquist sampling theorem and is usually selected as several times of the power frequency (such as above 2kHz) to ensure that the dynamic changes and harmonic characteristics of the voltage signal are fully recorded. The collected signal is a three-phase signal data stream, which is recorded as the original voltage signal of the first stage.

[0028] The collected three-phase voltage signals are low-pass filtered to remove high-frequency noise and harmonic interference in the signal and retain the power frequency signal component of the power grid. The filter design uses a second-order low-pass filter, and the cut-off frequency is set higher than the power frequency signal (for example, 60Hz) to ensure the integrity of the signal spectrum. The filter acts on the three-phase signal separately, and the signal obtained after filtering is the second-stage filtered voltage signal, which has good frequency characteristics.

[0029] The filtered three-phase voltage signal is processed by a phase-locked loop (PLL) to eliminate the phase offset problem caused by short-term disturbances or equipment interference in the power grid. The phase-locked loop uses the phase difference between the input signal and the reference signal to dynamically adjust the phase relationship of the three-phase signal to ensure that the signals maintain strict synchronization of the power frequency fundamental wave. The processed signal is a third-stage synchronous voltage signal with a unified phase reference.

[0030] The synchronized three-phase signal is subjected to mean removal processing to eliminate the DC offset introduced by the sensor or measuring device. After mean removal, the signal amplitude is normalized to adjust the signal amplitude to the normalized range of the rated voltage (for example, normalized to 1.0 pu). This processing unifies the amplitude reference of the signal and reduces the impact of amplitude error. The normalized signal is the fourth-stage standardized voltage signal.

[0031] The sliding window method is applied to the normalized signal to detect and remove outliers in the signal. The sliding window is used to calculate the local statistical characteristics of the signal, including the mean and standard deviation, and to remove abnormal data points that are beyond the normal range (such as more than three times the standard deviation of the mean). After the outliers are removed, the signal replaces the outliers by interpolation or neighboring values ​​to ensure the continuity of the data. After removing the outliers, the fifth stage preprocessed voltage signal is obtained, which has stable frequency characteristics, amplitude characteristics, and phase characteristics.

[0032] The dynamic state factor is expressed as, , , , , , in, Represents the fundamental component of the three-phase voltage, represents the sampling period, Represents the three-phase instantaneous voltage signal, represents the standard deviation of voltage fluctuation, represents the total number of sampling points, Indicates The sampled voltage value, Represents the average value of the voltage sampling value, Indicates the grid frequency offset, Indicates the real-time measured grid frequency. Indicates the rated frequency of the power grid, Indicates the unbalance of the three-phase voltage. Represents the instantaneous amplitude of the three-phase voltage, represents the gain factor, Represents the dynamic state factor.

[0033] It should be noted that the coefficients involved in the dynamic state factor It should be obtained by joint determination. This is because the voltage fluctuation standard deviation , Grid frequency offset and the unbalance of the three-phase voltage In dynamic state factor The joint determination coefficient can ensure that each factor has a synergistic effect on The contribution of the coefficient is balanced and adapted to the specific grid conditions. The initial value of the coefficient can be determined by offline experiments combined with historical grid operation data and optimized according to the following principles: It is suitable for describing the sensitivity of voltage fluctuations to wind turbine operation, and sets a higher initial value in high-fluctuation scenarios; The influence weight of the grid frequency offset can be set according to the frequency response curve of the wind turbine; It is used to reflect the impact of the imbalance of three-phase voltage and needs to match the grid voltage balance level.

[0034] Further explanation: Joint optimization can adopt weighted linear regression method based on experimental data or multi-objective optimization method. By inputting multiple sets of historical operation data, the optimization objective function takes into account the stability, sensitivity and operation safety of the dynamic state factor. For example, in the case of significant fluctuations, the and The weight of . Finally, a set of optimization coefficients suitable for specific grid conditions is generated.

[0035] Furthermore, joint optimization can also introduce a real-time adjustment mechanism to dynamically adjust the coefficients based on the voltage fluctuations, frequency deviations and imbalances monitored in real time. For example, in the case of severe fluctuations but stable frequency, the real-time reduction In the fast frequency offset scenario, increase and appropriately reduce Through the dual input of historical operation data and online data, the coefficient is dynamically adjusted to adapt to the power grid operation environment.

[0036] The trend factor is expressed as, , , , in, represents the trend factor, represents the rate of change of the dynamic state factor, represents the time series trend index, Represents the dynamic state factor of the current moment and the previous moment, represents the sampling time interval, represents the time series weight factor, Indicates The dynamic state factor at the moment, Indicates the length of the time series.

[0037] It should be noted that the trend factor is calculated by the rate of change of the dynamic state factor and Time Series Trend Index The change rate of the dynamic state factor reflects the rapid change of the current power grid state, while the time series trend index describes the continuity of the historical dynamic state to the trend. The combination of the two can fully reflect the dynamic characteristics of the power grid.

[0038] Further explanation: Time series trend index The length of the time series and the time series weight factor The deceleration rate of the weight factor needs to be set according to the change amplitude of the dynamic state factor and the fluctuation characteristics of the power grid. For example, when the dynamic state factor fluctuates slightly, the deceleration rate of the weight factor can be set to be slower (such as exponential decrease) to increase the influence of historical data; in the fast fluctuation scenario, a linearly decreasing weight distribution method can be used to enhance the real-time nature of the trend factor.

[0039] Further explanation: In order to improve the adaptability of trend factors, an adaptive adjustment mechanism based on time series prediction can be introduced. For example, the rate of change of dynamic state factors Adjusting time series length and the time series weight factor In fast-changing scenarios, shorten the time series length to increase real-time performance; in stable scenarios, extend the time series length to smooth the trend factor changes.

[0040] The reactive power instruction is expressed as, , , in, Represents reactive current, Indicates reactive power command, represents the trend factor, Indicates the trigger threshold of the trend factor, Represents the gain factor of reactive current, Indicates the bus voltage.

[0041] It should be noted that the reactive power command is determined by the reactive current and bus voltage Calculate together. Gain factor of reactive current It is used to adjust the response amplitude of reactive current to trend factor. Its initial value can be set by combining the reactive power curve of wind turbine with the operation characteristics of power grid. It is used to judge whether the trend factor has reached the critical condition for adjusting reactive power. Its initial value needs to be set in combination with the grid stability requirements.

[0042] Further explanation: the gain factor of reactive current is The dynamic adjustment of the trend factor needs to be combined with the rate of change of the trend factor. For example, when the trend factor changes slowly, the To reduce the adjustment range; when the trend factor changes rapidly, appropriately increase To enhance responsiveness. Trigger threshold It can be adjusted dynamically according to the real-time status of bus voltage fluctuations. For example, when the bus voltage is stable, the threshold is appropriately increased to avoid frequent adjustments; when the bus voltage fluctuates violently, the threshold is appropriately lowered to increase the response speed.

[0043] Further explanation: By combining the real-time monitored bus voltage fluctuation range and trend factor change characteristics, a dynamic adjustment model for reactive power instructions is constructed. For example, the trigger threshold is adjusted in advance by predicting the change direction of the trend factor. , or optimize the gain factor of reactive current in combination with the current operating status of the wind turbine (such as blade angle and speed) dynamic range.

[0044] The theoretical active power value is expressed as, , , , , in, Indicates the theoretical active power value, Indicates the rated active power of the fan. represents the trend factor, represents the maximum value of the trend factor, Indicates the dynamic reactive power change rate, Indicates the rated value of reactive power, Indicates the reactive power at the current and previous moment, Indicates the fan speed deviation. Indicates the rated speed of the fan. Indicates the maximum speed deviation. Indicates the real-time wind speed. Indicates the rated wind speed of the fan. Represents the wind speed impact factor.

[0045] It should be noted that the theoretical active power value The calculation of the dynamic reactive power change rate needs to clarify the acquisition method and calculation logic of each input parameter. Calculate the time difference of reactive power command; fan speed deviation The wind speed influence factor is obtained by the difference between the real-time measured fan speed and the rated speed. It is calculated by the ratio of real-time wind speed to rated wind speed.

[0046] Further explanation: the dynamic adjustment of each parameter needs to be combined with the operating characteristics of the wind turbine and the real-time status of the power grid. When the wind speed is close to the rated value, the value is 1.0; when the wind speed is low or high, the wind speed deviation can be compensated by adjusting the blade angle. Dynamic reactive power change rate The calculation needs to reduce the adjustment frequency when the power command changes smoothly, and speed up the response when the change is large.

[0047] Further explanation: In order to enhance the adaptability of the theoretical active power value, the weights of the parameters in the formula can be dynamically adjusted under different operating conditions. For example, in a scenario where the grid frequency deviation is significant, it is appropriate to increase The weight of the frequency is increased to enhance the effect of frequency on power. In scenarios with large wind speed fluctuations, The weights respond quickly to wind speed changes.

[0048] The dynamic adjustment of the active power output of the wind turbine generator system includes adjusting the theoretical active power value Perform limiting processing; set the rated output power upper limit of the wind turbine and minimum operating power As the power limit boundary; when When the output power is adjusted to ;when When the output power is adjusted to ;when ≤ ≤ When unchanged; the power value after limiting is ; Get the current operating power of the fan And the power value after limiting The difference between them is expressed as, ; According to the maximum power change rate Set the adjustment range when > When the power is adjusted to ;when < When the power is adjusted to ;when ≤ ≤ When The result after power adjustment is ; Based on the power adjustment results Generate output power command; send power adjustment result and power adjustment rate to wind turbine control system; adjust blade angle, speed and converter operation status through wind turbine control system; the adjusted wind turbine output power is ; The power adjustment rate is expressed as, .

[0049] It should be noted that the dynamic adjustment of the wind turbine active power output limit processing needs to be combined with the upper and lower limits of the wind turbine operating power. For example, when the wind speed is high, the power limit can be appropriately increased. To make full use of wind energy; when the wind speed is low, reduce the power limit To protect the equipment.

[0050] Further explanation: Power smoothing adjustment needs to be done by monitoring and Dynamic optimization of the matching. For example, in a scene with stable wind speed changes, reducing To reduce the adjustment range; in the scene of drastic changes in wind speed, increase To enhance the sensitivity of the adjustment.

[0051] To further explain, the power limit range and adjustment rate are dynamically adjusted in combination with the real-time monitored wind speed and the operating status of the wind turbine (such as blade angle and speed). For example, the stability of power output is optimized by reducing the impact of speed deviation; under complex operating conditions, the stability and safety of the power adjustment process are ensured by dynamically adjusting the limit parameters and power smoothing strategy.

[0052] The trend factor is used twice to serve different control objectives. The first one is used to generate reactive power instructions. Through the reactive current adjustment of the grid-side converter, it quickly responds to the dynamic demand of the power grid and ensures the voltage stability of the power grid. The second one combines the reactive power instructions and the mechanical characteristic parameters of the wind turbine to generate the theoretical active power value and realize the optimization adjustment of the operation of the wind turbine. This design avoids the logical conflict between reactive adjustment and active adjustment.

[0053] The first use of the trend factor reflects its sensitivity to changes in grid conditions, such as voltage fluctuations, frequency offsets, and three-phase imbalance. Dynamically adjusting the reactive current output of the grid-side converter through the trend factor can effectively compensate for the reactive power demand in the grid, mitigate voltage fluctuations, and improve grid stability. The priority of reactive power adjustment is based on the service attributes of wind turbines to the grid, reflecting the necessity and importance of rapid response.

[0054] The second use of the trend factor combines the reactive power command and the mechanical characteristic parameters of the wind turbine. The significance of this combination is to pass the result of reactive power adjustment to the active power optimization, ensuring that the active power adjustment not only meets the needs of the power grid, but also takes into account the operating status of the wind turbine itself. This progressive control method takes into account both the dynamic needs of the power grid and the operating safety and efficiency of the wind turbine.

[0055] The two applications of trend factors form a closed-loop control design logic. The first reactive power adjustment provides direct support for the power grid, and the second active power optimization is a further response of the wind turbine to adapt to the power grid trend. This design ensures a clear hierarchy between reactive power and active power adjustment, and at the same time, through the multi-dimensional application of trend factors, the overall coordination and stability of the control system are enhanced.

[0056] The advantages of this design are reflected in the following aspects: First, the trend factor is used twice to avoid the introduction of new calculation indicators and simplify the complexity of the control system; second, the reactive power adjustment is connected with the active power optimization, which not only meets the real-time needs of the power grid, but also takes into account the global optimization of wind turbine operation; third, through the multiple effects of the trend factor, an efficient interaction mechanism between the power grid status and the wind turbine operation is formed, which improves the dynamic adaptability of the wind turbine and the stability of the power grid.

[0057] Example 2

[0058] Reference Figure 2 , which is an embodiment of the present invention, provides a high voltage ride through control system for a wind turbine generator set, comprising: Data acquisition module 100, state analysis module 200, trend analysis module 300, reactive power regulation module 400, active power calculation module 500 and power adjustment module 600; The data acquisition module 100 is used to collect the three-phase voltage signal of the power grid in real time and pre-process the three-phase voltage signal; The state analysis module 200 is used to calculate the voltage fundamental component, voltage fluctuation standard deviation, grid frequency offset and three-phase voltage imbalance based on the preprocessed three-phase voltage signal, generate a dynamic state factor for real-time characterization of the dynamic characteristics of the grid, and provide input for subsequent control strategies; The trend analysis module 300 is used to generate a trend factor according to the change rate of the dynamic state factor in combination with the time series trend index, which is used to quantify the dynamic trend of voltage fluctuation and serve as an influencing parameter for reactive power and active power adjustment; The reactive power regulation module 400 is used to dynamically adjust the reactive current output through the grid-side converter according to the trend factor, and generate reactive power instructions to suppress the increase of grid voltage, improve system voltage stability, and feed back the reactive power output result to the active power adjustment link; The active power calculation module 500 is used to generate a theoretical active power value according to the trend factor and the reactive power instruction combined with the mechanical characteristic parameters of the wind turbine; The power adjustment module 600 is used to generate an output power instruction of the wind turbine generator set based on the theoretical active power value, and dynamically adjust the active power output of the wind turbine generator set to improve the operation stability and grid adaptability of the wind turbine generator set.

[0059] Example 3

[0060] An embodiment of the present invention is different from the first two embodiments in that:

[0061] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0062] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0063] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0064] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0065] Example 4

[0066] As an embodiment of the present invention, a high voltage ride through control method for a wind turbine is provided. To verify the beneficial effects of the present invention, a scientific demonstration is carried out through simulation experiments.

[0067] The experimental environment is set in a simulated wind farm. The connected wind turbine is a direct-drive wind turbine with a rated power of 2 MW. The rated voltage of the connected power grid system is 1.0 pu, and the normal frequency of the power grid is 50 Hz. In the experiment, a short-term high-voltage event is simulated in the power grid, and the voltage rises rapidly from 1.0 pu to 1.3 pu, and then returns to 1.0 pu after 0.5 seconds. The response performance of the wind turbine under high voltage conditions is considered in the experiment, and the effect of the control method is verified by recording the dynamic changes of the reactive power and active power of the wind turbine. The experiment also sets up a real wind speed environment, and the wind speed is maintained in the fluctuation range of 10 m / s to 12 m / s to ensure that the wind turbine is within the rated power output range.

[0068] The control logic of the traditional method adopts a single voltage feedback regulation method. When the grid voltage increases, the wind turbine gradually adjusts the output of reactive current by measuring the bus voltage value to provide grid voltage support. Its technical solution is: collect grid voltage signals; generate reactive current instructions based on voltage deviations; adjust reactive power through reactive current output; active power is limited by a fixed value and is not actively adjusted dynamically. The adaptability of this method to grid voltage changes depends on the sensitivity of voltage feedback and fixed control parameters, and fails to fully consider dynamic grid characteristics.

[0069] The method of the present invention introduces dynamic state factors and trend factors for comprehensive regulation. The technical scheme is: collect and pre-process the three-phase voltage signal of the power grid to generate a dynamic state factor, combine the change rate of the dynamic state factor and the time series trend index to generate a trend factor; dynamically adjust the reactive current output of the grid-side converter based on the trend factor to generate a reactive power instruction; further combine the reactive power instruction with the mechanical characteristic parameters of the wind turbine to generate a theoretical active power value; finally, dynamically adjust the active power output of the wind turbine through limiting protection and smoothing adjustment. The method of the present invention comprehensively considers the dynamic characteristics of the power grid and the mechanical characteristics of the wind turbine, and can adapt to the changes in the power grid voltage more quickly and accurately.

[0070] During the experiment, the response time, reactive power fluctuation, active power fluctuation and steady-state deviation of the wind turbine under the two methods were recorded. The experimental results are shown in Table 1.

[0071] Table 1 Comparison of experimental results index Traditional methods Method of the present invention Response time (seconds) 0.9 0.4 Reactive power fluctuation (kVar) 180 45 Active power fluctuation (kW) 90 25 Steady state deviation (%) 4.5 1.2

[0072] Referring to Table 1, the experimental results show that under high voltage ride-through conditions, the performance of the method of the present invention is significantly better than that of the traditional method. From the perspective of response time, the method of the present invention can perceive dynamic changes in advance when the grid voltage rises rapidly, extract multiple parameters such as the voltage fundamental component and the voltage fluctuation standard deviation through dynamic state factors, and quickly and comprehensively generate the core parameters required for adjustment; at the same time, combined with the dynamic prediction ability of the trend factor, the regulation of reactive current can be quickly intervened when the high voltage event just occurs. In contrast, the traditional method relies entirely on the gradual feedback of the voltage deviation, and cannot make effective adjustments before the voltage deviation accumulates to the regulation threshold. The response time is slow, resulting in significant lag in power regulation.

[0073] In terms of the volatility of reactive power regulation, the method of the present invention introduces a regulation strategy that combines limiting protection and smoothing adjustment. By limiting the output rate of reactive power, overshoot and large fluctuations in the regulation process are avoided. Especially when the grid voltage recovers from a high value to a normal value, the method of the present invention can smoothly reduce the reactive power output, thereby maintaining the operational stability of the wind turbine and the grid. In traditional methods, the regulation process lacks a rate limiting mechanism, and the reactive power shows obvious overshoot during the grid voltage recovery phase, further exposing the lack of stability of traditional control logic in dynamic scenarios.

[0074] The experimental results of active power regulation show that the method of the present invention adjusts the theoretical active power value by combining the mechanical characteristic parameters of the wind turbine, and reduces the power fluctuation in the regulation process through dynamic smooth adjustment. This method can flexibly adjust the power output of the wind turbine when a high voltage event occurs in the power grid, which not only ensures the safe operation of the wind turbine, but also avoids the impact of power fluctuations on the power grid. However, the traditional method uses a fixed value limit in the regulation of active power, and fails to make dynamic adjustments according to the real-time power grid status. The power fluctuation is more significant under high voltage conditions, showing the problem of insufficient regulation flexibility.

[0075] In terms of steady-state deviation, the present invention comprehensively characterizes the dynamic characteristics of the grid voltage through the combined application of dynamic state factors and trend factors, making power regulation more accurate. The trend factor predicts the current grid voltage trend through the time series weight analysis of the historical state, thereby effectively reducing the steady-state deviation. However, the traditional method relies only on the adjustment of a single voltage parameter and cannot accurately predict the dynamic changes of the grid state, resulting in a large deviation between the final power regulation result and the target value.

[0076] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A high voltage ride through control method for a wind turbine generator system, characterized in that: include: Collect the three-phase voltage signal of the power grid in real time and pre-process the three-phase voltage signal; Based on the preprocessed three-phase voltage signal, the voltage fundamental component, the voltage fluctuation standard deviation, the grid frequency offset and the three-phase voltage imbalance are calculated to generate a dynamic state factor; According to the rate of change of the dynamic state factor, combined with the time series trend index, a trend factor is generated; According to the trend factor, dynamically adjusting reactive current output through the grid-side converter and generating reactive power instructions; Generate a theoretical active power value according to the trend factor and the reactive power command combined with the mechanical characteristic parameters of the wind turbine; The output power command of the wind turbine is generated based on the theoretical active power value, and the active power output of the wind turbine is dynamically adjusted.

2. The high voltage ride through control method for a wind turbine generator set according to claim 1, characterized in that: The preprocessing includes low-pass filtering the three-phase voltage signal; Perform phase-locked synchronization processing on the low-pass filtered signal; Perform mean removal and amplitude normalization on the synchronized signal; The normalized signal is subjected to sliding window outlier removal to obtain the preprocessed three-phase voltage signal.

3. The high voltage ride through control method for a wind turbine generator set according to claim 2, characterized in that: The dynamic state factor is expressed as, ， ， ， ， ， in, Represents the fundamental component of the three-phase voltage, represents the sampling period, Represents the three-phase instantaneous voltage signal, represents the standard deviation of voltage fluctuation, represents the total number of sampling points, Indicates The sampled voltage value, Represents the average value of the voltage sampling value, Indicates the grid frequency offset, Indicates the real-time measured grid frequency. Indicates the rated frequency of the power grid, Indicates the unbalance of the three-phase voltage. Represents the instantaneous amplitude of the three-phase voltage, represents the gain factor, Represents the dynamic state factor.

4. The high voltage ride through control method for a wind turbine generator set as claimed in claim 3, characterized in that: The trend factor is expressed as, ， ， ， in, represents the trend factor, represents the rate of change of the dynamic state factor, represents the time series trend index, Represents the dynamic state factor of the current moment and the previous moment, represents the sampling time interval, represents the time series weight factor, Indicates The dynamic state factor at the moment, Indicates the length of the time series.

5. The high voltage ride through control method for a wind turbine generator set according to claim 4, characterized in that: The reactive power instruction is expressed as, ， ， in, Represents reactive current, Indicates reactive power command, Indicates the trigger threshold of the trend factor, Represents the gain factor of reactive current, Indicates the bus voltage.

6. The high voltage ride through control method for a wind turbine generator set according to claim 5, characterized in that: The theoretical active power value is expressed as, ， ， ， ， in, Indicates the theoretical active power value, Indicates the rated active power of the fan. represents the maximum value of the trend factor, Indicates the dynamic reactive power change rate, Indicates the rated value of reactive power, Indicates the reactive power at the current and previous moment, Indicates the fan speed deviation. Indicates the rated speed of the fan. Indicates the maximum speed deviation. Indicates the real-time wind speed. Indicates the rated wind speed of the fan. Represents the wind speed impact factor.

7. The high voltage ride through control method for a wind turbine generator set according to claim 6, characterized in that: The dynamic adjustment of the active power output of the wind turbine generator system includes adjusting the theoretical active power value Perform limiting processing; set the rated output power upper limit of the wind turbine and minimum operating power As the power limit boundary; when When the output power is adjusted to ;when When the output power is adjusted to ;when ≤ ≤ When unchanged; the power value after limiting is ; Get the current operating power of the fan And the power value after limiting The difference between them is expressed as, ; According to the maximum power change rate Set the adjustment range when > When the power is adjusted to ;when < When the power is adjusted to ;when ≤ ≤ When The result after power adjustment is ; Based on the power adjustment results Generate output power command; send power adjustment result and power adjustment rate to wind turbine control system; adjust blade angle, speed and converter operation status through wind turbine control system; the adjusted wind turbine output power is ; The power adjustment rate is expressed as, 。 8. A system using the high voltage ride through control method for a wind turbine as claimed in any one of claims 1 to 7, characterized in that: include: A data acquisition module (100), a state analysis module (200), a trend analysis module (300), a reactive power regulation module (400), an active power calculation module (500), and a power adjustment module (600); The data acquisition module (100) is used to collect three-phase voltage signals of the power grid in real time and pre-process the three-phase voltage signals; The state analysis module (200) is used to calculate the voltage fundamental component, the voltage fluctuation standard deviation, the grid frequency offset and the three-phase voltage imbalance based on the preprocessed three-phase voltage signal, and generate a dynamic state factor; The trend analysis module (300) is used to generate a trend factor according to the change rate of the dynamic state factor in combination with the time series trend index; The reactive power regulation module (400) is used to dynamically adjust reactive current output through the grid-side converter according to the trend factor, and generate reactive power instructions; The active power calculation module (500) is used to generate a theoretical active power value according to the trend factor and the reactive power instruction combined with the mechanical characteristic parameters of the wind turbine; The power adjustment module (600) is used to generate an output power instruction of the wind turbine generator set based on a theoretical active power value, and to dynamically adjust the active power output of the wind turbine generator set.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the high voltage ride through control method for a wind turbine set as described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the high voltage ride through control method for a wind turbine set according to any one of claims 1 to 7 are implemented.

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