A high-voltage ride-through control method, system, device and medium for a wind turbine

Abstract

The present invention discloses a high-voltage ride-through control method, system, device and medium for a wind turbine generator set, which relates to the technical field of wind power and includes: collecting three-phase grid voltage signals in real time; generating a dynamic state factor based on the preprocessed three-phase voltage signals; generating a trend factor according to the change rate of the dynamic state factor in combination with a time series trend index; dynamically adjusting the reactive current output through a grid-side converter according to the trend factor and generating a reactive power command; generating a theoretical active power value according to the trend factor and the reactive power command in combination with the mechanical characteristic parameters of the wind turbine; and dynamically adjusting the active power output of the wind turbine generator set. The high-voltage ride-through control method for the wind turbine generator set provided by the present invention solves the problems of response lag, insufficient regulation accuracy and excessive power fluctuation, and avoids the overshoot phenomenon during the power regulation process; through dynamic smoothing adjustment, the power fluctuation is reduced, and the operation stability and regulation accuracy of the wind turbine generator set during high-voltage ride-through are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, and particularly to a high-voltage ride-through control method, system, device and medium for a wind turbine generator set. Background Art

[0002] With the rapid development of wind power technology, the scale of wind farms is constantly expanding, and the operating performance of grid-connected wind turbines has a more significant impact on the stability of the power grid. When a wind turbine generator set is connected to the grid for operation, it not only needs to meet the requirements of power generation efficiency and operation safety, but also needs to have the adaptability under abnormal grid conditions, especially the high-voltage ride-through ability. The high-voltage ride-through requires that when the grid voltage rises to a certain range, the wind turbine generator set can maintain stable operation and provide reactive power support to ensure the stability of the power grid system.

[0003] In the prior art, the high-voltage ride-through control method of a wind turbine generator set usually realizes it by adjusting the reactive power and active power. However, the traditional control method has the following deficiencies: on the one hand, the dynamic response is lagging, resulting in the inability of the wind turbine generator set to make timely adjustments when the grid voltage changes, which may cause unstable operation or even the risk of grid disconnection; 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 the actual requirements. In addition, the traditional method lacks comprehensive consideration of the mechanical characteristics of the fan during the power adjustment process, and it is easy to have problems such as overshoot or excessive power fluctuation during adjustment, which will affect the service life of the fan and the stability of the power grid.

[0004] To address the above challenges, in recent years, a wind turbine generator set control strategy based on multiple parameters has been gradually proposed, such as a comprehensive control method that introduces reactive current regulation and dynamic monitoring of the grid voltage. However, these methods still face problems such as high engineering complexity and insufficient 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 comprehensively consider multiple grid state parameters and quickly and stably adjust the output power of the fan to improve the operation reliability of the wind turbine generator set and the adaptability to the power grid. Summary of the Invention

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

[0006] Therefore, the technical problems solved by the present invention are: the existing high-voltage ride-through control method for wind turbine generator sets has problems such as response lag, insufficient adjustment accuracy, excessive power fluctuation, and incomplete characterization of the dynamic characteristics of the power grid, and the optimization problem of how to improve the dynamic response ability and adjustment stability of the fan in a complex grid environment.

[0007] 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 set, including:

[0008] Collect the three-phase voltage signals of the power grid in real time and preprocess the three-phase voltage signals;

[0009] Calculate the fundamental voltage component, the standard deviation of voltage fluctuation, the power grid frequency deviation, and the three-phase voltage unbalance degree based on the preprocessed three-phase voltage signals, and generate a dynamic state factor;

[0010] Generate a trend factor according to the change rate of the dynamic state factor and in combination with the time series trend index;

[0011] According to the trend factor, dynamically adjust the reactive current output through the grid-side converter and generate a reactive power command;

[0012] Generate a theoretical active power value according to the trend factor and the reactive power command in combination with the fan mechanical characteristic parameters;

[0013] Generate an output power command for the wind turbine based on the theoretical active power value and dynamically adjust the active power output of the wind turbine.

[0014] As a preferred solution of the high-voltage ride-through control method for the wind turbine described in the present invention, wherein: the preprocessing includes low-pass filtering the three-phase voltage signals;

[0015] Perform phase-locked synchronization processing on the low-pass filtered signal;

[0016] Perform mean removal and amplitude normalization on the synchronized signal;

[0017] Perform sliding window outlier rejection on the normalized signal to obtain the preprocessed three-phase voltage signals.

[0018] As a preferred solution of the high-voltage ride-through control method for the wind turbine described in the present invention, wherein: the dynamic state factor is expressed as,

[0019] F dyn =V base +k σ ·σ V +k f ·Δf+k u ·U imbalance

[0020]

[0021] Δf=f measured -f rated

[0022]

[0023] Among them, V base represents the fundamental component of the three-phase voltage, T represents the sampling period, v a(t), v b (t), v c (t) represents the three-phase instantaneous voltage signal, σ V represents the standard deviation of voltage fluctuation, n represents the total number of sampling points, V i represents the i-th sampled voltage value, represents the average value of the voltage sampling values, Δf represents the power grid frequency offset, f measured represents the power grid frequency measured in real time, f rated represents the rated frequency of the power grid, U imbalance represents the unbalance degree of the three-phase voltage, V a , V b , V c represents the instantaneous amplitude of the three-phase voltage, k σ , k f , k u represents the gain coefficient, F dyn represents the dynamic state factor.

[0024] As a preferred solution of the high-voltage ride-through control method for the wind turbine generator set described in the present invention, wherein: the trend factor is expressed as,

[0025] T trend = ΔF dyn + T index

[0026]

[0027] wherein, T trend represents the trend factor, ΔF dyn represents the change rate of the dynamic state factor, T index represents the time series trend index, F dyn,t , F dyn,t-1 represents the dynamic state factors at the current moment and the previous moment, Δt represents the sampling time interval, w i represents the time series weight factor, F dyn,i represents the dynamic state factor at the i-th moment, L represents the length of the time series.

[0028] As a preferred solution of the high-voltage ride-through control method for the wind turbine generator set described in the present invention, wherein: the reactive power command is expressed as,

[0029] Q new = I Q ·V bus

[0030] I Q = k Q ·max(0, T trend - T threshold )

[0031] Among them, I Q represents the reactive current, and Q new represents the reactive power command, T trend represents the trend factor, and T threshold represents the trigger threshold of the trend factor, and k Q represents the gain coefficient of the reactive current, and V bus represents the bus voltage.

[0032] As a preferred solution of the high-voltage ride-through control method for a wind turbine according to the present invention, among them: the theoretical active power value is expressed as

[0033]

[0034] Δω = ω measured -ω rated

[0035]

[0036] Among them, P new represents the theoretical active power value, P rated represents the rated active power of the wind turbine, T trend represents the trend factor, T max represents the maximum value of the trend factor, ΔQ new represents the dynamic reactive power change rate, Q rated represents the rated value of the reactive power, Q new,t , Q new,t-1 represents the reactive power at the current and previous moments, Δω represents the wind turbine speed deviation, ω rated represents the rated speed of the wind turbine, Δω max represents the maximum value of the speed deviation, V wind represents the real-time wind speed, V rated represents the rated wind speed of the wind turbine, k wind represents the wind speed influence factor.

[0037] As a preferred solution of the high-voltage ride-through control method for a wind turbine according to the present invention, among them: the dynamic adjustment of the active power output of the wind turbine includes limiting the theoretical active power value P new ; taking the upper limit P max of the rated output power of the wind turbine and the minimum operating power P min as the power limit boundary; when P new > P max , adjusting the output power to P max ; when P new < P min , adjusting the output power to P min ; when P min ≤ Pnew ≤P max When it is, keep P new unchanged; the power value after amplitude limiting processing is P limit ;

[0038] Obtain the operating power P of the current wind turbine current and the power value P after amplitude limiting processing limit The difference between them is expressed as ΔP = P limit -P current ; According to the maximum power change rate R P,max Set the adjustment range. When ΔP > R P,max ·Δt, adjust the power to P current +R P,max ·Δt; when ΔP < -R P,max ·Δt, adjust the power to P current -R P,max ·Δt; when -R P,max ·Δt ≤ ΔP ≤ R P,max ·Δt, keep P limit unchanged, and the result of power adjustment is P smooth ;

[0039] Generate an output power command based on the power adjustment result P smooth ; Send the power adjustment result and the power adjustment rate to the wind turbine control system; through the control system of the wind turbine, adjust the blade angle, speed and converter operating state; the adjusted wind turbine output power is P output ;

[0040] The power adjustment rate is expressed as

[0041]

[0042] 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 change of the grid voltage in time, the regulation fluctuation is too large due to the lack of rate limitation in the power adjustment process, and the regulation error caused by insufficient signal preprocessing accuracy by constructing a high-voltage ride-through control system for a wind turbine.

[0043] 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 three-phase grid voltage signals in real time and preprocess the three-phase voltage signals; the state analysis module is used to calculate the voltage fundamental component, the standard deviation of voltage fluctuation, the grid frequency deviation, and the three-phase voltage unbalance degree based on the preprocessed three-phase voltage signals, and 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 and in combination with the 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 command; the active power calculation module is used to generate a theoretical active power value according to the trend factor and the reactive power command in combination with the wind turbine mechanical characteristic parameters; the power adjustment module is used to generate an output power command for the wind turbine based on the theoretical active power value and dynamically adjust the active power output of the wind turbine.

[0044] A computer device, comprising a memory and a processor, where the memory stores a computer program, and when the processor executes the computer program, the steps of the above-mentioned high-voltage ride-through control method for a wind turbine are implemented.

[0045] A computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above-mentioned high-voltage ride-through control method for a wind turbine are implemented.

[0046] The beneficial effects of the present invention: The high-voltage ride-through control method for a wind turbine provided by the present invention solves the problems of response lag, insufficient adjustment accuracy, and excessive power fluctuation in the prior art by generating a dynamic state factor and a trend factor. The dynamic state factor is generated based on the calculation results of the grid voltage fundamental component, the standard deviation of voltage fluctuation, the grid frequency deviation, and the three-phase voltage unbalance degree, comprehensively characterizing 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 adjustment of reactive power and active power by reflecting the dynamic trend of the grid. In the process of power adjustment of the present invention, through amplitude limiting protection and power change rate constraint, the overshoot phenomenon in the power adjustment process is avoided; through dynamic smooth adjustment, the power fluctuation is reduced, ensuring the operation stability and adjustment accuracy of the wind turbine during high-voltage ride-through, and meeting the high requirements of modern power grids. Description of the Drawings

[0047] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0048] Figure 1 This is the overall flowchart of a high-voltage ride-through control method for a wind turbine provided by an embodiment of the present invention.

[0049] Figure 2 This is the overall structure diagram of a high-voltage ride-through control system for a wind turbine provided by the second embodiment of the present invention. Detailed implementation manners

[0050] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following will make a detailed description of the specific implementation manners of the present invention in conjunction with the accompanying drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0051] In the following description, many specific details are set forth to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0052] Embodiment 1

[0053] Refer to Figure 1 , which is an embodiment of the present invention, and provides a high-voltage ride-through control method for a wind turbine, including:

[0054] S1: Real-time collect the three-phase voltage signals of the power grid and preprocess the three-phase voltage signals;

[0055] S2: Calculate the voltage fundamental component, voltage fluctuation standard deviation, power grid frequency deviation, and three-phase voltage unbalance degree based on the preprocessed three-phase voltage signals, and generate a dynamic state factor;

[0056] S3: Generate a trend factor according to the change rate of the dynamic state factor in combination with the time series trend index;

[0057] S4: According to the trend factor, dynamically adjust the reactive current output through the grid-side converter and generate a reactive power command;

[0058] S5 generates a theoretical active power value based on the trend factor and the reactive power command in combination with the fan mechanical characteristic parameters;

[0059] S6 generates an output power command for the wind turbine based on the theoretical active power value and dynamically adjusts the active power output of the wind turbine.

[0060] The preprocessing includes low-pass filtering of the three-phase voltage signal;

[0061] Performs phase-locked synchronization processing on the low-pass filtered signal;

[0062] Performs mean removal and amplitude normalization on the synchronized signal;

[0063] Removes outliers in the normalized signal through a sliding window to obtain the preprocessed three-phase voltage signal.

[0064] The three-phase voltage signal of the power grid is collected in real time through a voltage sensor and a sampling device, and the instantaneous value of each phase voltage is recorded respectively. The sampling frequency of the sampling device should satisfy the Nyquist sampling theorem and is usually selected as several times the power frequency (such as above 2 kHz) to ensure complete recording of the dynamic changes and harmonic characteristics of the voltage signal. The collected signal is a three-phase signal data stream, denoted as the original voltage signal in the first stage.

[0065] The collected three-phase voltage signals are respectively subjected to low-pass filtering processing to remove high-frequency noise and harmonic interference in the signals and retain the power grid power frequency signal components. 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, 60 Hz) to ensure the integrity of the signal spectrum. The filter acts on the three-phase signals respectively, and the filtered signal is the filtered voltage signal in the second stage, which has good frequency characteristics.

[0066] The filtered three-phase voltage signals are processed by a phase-locked loop (PLL) to eliminate the phase shift 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 signals to ensure strict synchronization of the power frequency fundamental waves between the signals. The processed signal is the synchronized voltage signal in the third stage, which has a unified phase reference.

[0067] The synchronized three-phase signals are subjected to mean removal processing to eliminate the DC offset introduced by the sensor or measurement device. After mean removal, the signal amplitude is normalized, and the signal amplitude is adjusted 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 influence of amplitude error. The normalized signal is the standardized voltage signal in the fourth stage.

[0068] Apply the sliding window method 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 remove the abnormal data points that exceed the normal range (such as more than three times the standard deviation of the mean). After removing the outliers, the signal interpolates or replaces the abnormal points with neighboring values to ensure the continuity of the data. After removing the outliers, the preprocessed voltage signal in the fifth stage is obtained, and this signal has stable frequency characteristics, amplitude characteristics, and phase characteristics.

[0069] The dynamic state factor is expressed as

[0070] F dyn =V base +k σ ·σ V +k f ·Δf + k u ·U imbalance

[0071]

[0072] Δf = f measured -f rated

[0073]

[0074] Where, V base represents the fundamental component of the three-phase voltage, T represents the sampling period, v a (t), v b (t), v c (t) represent the three-phase instantaneous voltage signals, σ V represents the standard deviation of voltage fluctuation, n represents the total number of sampling points, V i represents the i-th sampling voltage value, represents the average value of voltage sampling values, Δf represents the power grid frequency offset, f measured represents the power grid frequency measured in real time, f rated represents the rated frequency of the power grid, U imbalance represents the unbalance degree of the three-phase voltage, V a , V b , V c represent the instantaneous amplitudes of the three-phase voltages, k σ , k f , k u represent the gain coefficients, F dyn represents the dynamic state factor.

[0075] It should be noted that the coefficients k σ , k f , k uIt should be obtained through a jointly determined method. This is because the standard deviation of voltage fluctuation σ V , the grid frequency deviation Δf, and the unbalance degree U of the three-phase voltage imbalance act synergistically in the calculation of the dynamic state factor F dyn . The jointly determined coefficient can ensure that the contributions of various factors to F dyn are balanced and adapted to specific grid conditions. The initial value of the coefficient can be determined through offline experiments combined with historical grid operation data and optimized according to the following principles: k σ is applicable to describe the sensitivity of the impact of voltage fluctuation on the operation of the fan, and a higher initial value is set in high-fluctuation scenarios; k f reflects the influence weight of frequency deviation and can be set according to the frequency response curve of the wind turbine; k u is used to reflect the degree of influence of voltage unbalance and needs to match the grid voltage balance level.

[0076] Furthermore, joint optimization can adopt a weighted linear regression method or a multi-objective optimization method based on experimental data. By inputting multiple sets of historical operation data, the optimization objective function comprehensively considers the stability, sensitivity of the dynamic state factor, and the operation safety of the wind turbine. For example, in scenarios with significant fluctuations, increase the weights of k σ and k u , while in scenarios with severe frequency deviation, give priority to increasing k f . Finally, a set of optimized coefficients applicable to specific grid conditions is generated.

[0077] Even further explanation, joint optimization can also introduce a real-time adjustment mechanism to dynamically adjust the coefficients according to the real-time monitored voltage fluctuation, frequency deviation, and unbalance degree. For example, in the case of severe fluctuations but stable frequency, reduce the weight of k f in real time; in scenarios of rapid frequency deviation, increase k f and appropriately reduce k σ . Through the dual input of historical operation data and online data, dynamically adjust the coefficients to adapt to the grid operation environment.

[0078] The trend factor is expressed as,

[0079] T trend =ΔF dyn +T index

[0080]

[0081] where, T trend represents the trend factor, ΔF dyn represents the change rate of the dynamic state factor, T index represents the time-series trend index, F dyn,t ,Fdyn,t-1 represents the dynamic state factors at the current moment and the previous moment, Δt represents the sampling time interval, and w i represents the time series weight factor, F dyn,i represents the dynamic state factor at the i-th moment, and L represents the length of the time series.

[0082] It should be noted that the calculation of the trend factor is determined by the change rate ΔF of the dynamic state factor dyn and the time series trend index T index jointly. 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 on the trend. The combination of the two can comprehensively reflect the dynamic characteristics of the power grid.

[0083] Furthermore, for the time series length L of the time series trend index T index and the time series weight factor w i the decreasing rate needs to be set according to the change amplitude of the dynamic state factor and the power grid fluctuation characteristics. For example, when the fluctuation of the dynamic state factor is small, the decreasing rate of the weight factor can be set to be relatively slow (such as exponential decay) to increase the influence of historical data; while in the fast fluctuation scenario, a linear decreasing weight allocation method can be adopted to enhance the real-time performance of the trend factor.

[0084] Even further, to improve the adaptability of the trend factor, an adaptive adjustment mechanism based on time series prediction can be introduced. For example, by the change rate ΔF of the dynamic state factor dyn adjust the distribution rules of the time series length L and the time series weight factor w i In the fast-changing scenario, shorten the time series length to increase real-time performance; in the stable scenario, extend the time series to smooth the change of the trend factor.

[0085] The reactive power command is expressed as,

[0086] Q new = I Q · V bus

[0087] I Q = k Q · max(0, T trend - T threshold )

[0088] where, I Q represents the reactive current, Q new represents the reactive power command, T trend represents the trend factor, T threshold represents the trigger threshold of the trend factor, and k Q represents the gain coefficient of the reactive current, V busIndicates the bus voltage.

[0089] It should be noted that the reactive power command is jointly calculated by the reactive current I Q and the bus voltage V bus The gain coefficient k of the reactive current Q is used to adjust the response amplitude of the reactive current to the trend factor, and its initial value can be set by combining the reactive power curve of the wind turbine with the grid operation characteristics. The trigger threshold T threshold is used to judge whether the trend factor reaches the critical condition for adjusting the reactive power, and its initial value needs to be set in combination with the grid stability requirements.

[0090] Furthermore, the dynamic adjustment of the gain coefficient k of the reactive current Q needs to be combined with the change rate of the trend factor. For example, when the trend factor changes slowly, k Q can be reduced to reduce the adjustment amplitude; while when the trend factor changes rapidly, k Q is appropriately increased to enhance the response ability. The trigger threshold T threshold can be dynamically adjusted according to the real-time state of the bus voltage fluctuation. For example, when the bus voltage is stable, the threshold is appropriately increased to avoid frequent adjustment; when the fluctuation is severe, the threshold is appropriately reduced to improve the response speed.

[0091] Even further, combining the real-time monitored bus voltage fluctuation range and the trend factor change characteristics, a dynamic adjustment model of the reactive power command is constructed. For example, by predicting the change direction of the trend factor, the trigger threshold T threshold is adjusted in advance, or the dynamic range of the gain coefficient k of the reactive current is optimized by combining the current operating state of the wind turbine (such as blade angle and speed). Q

[0092] The theoretical active power value is expressed as

[0093]

[0094] Δω = ω measured - ω rated

[0095]

[0096] where P new represents the theoretical active power value, P rated represents the rated active power of the fan, T trend represents the trend factor, T max represents the maximum value of the trend factor, ΔQ new represents the dynamic reactive power change rate, Q rated represents the rated value of the reactive power, Q new,t , Q new,t-1represents the reactive power at the current and previous moments, Δω represents the deviation of the wind turbine speed, and ω rated represents the rated speed of the wind turbine, and Δω max represents the maximum value of the speed deviation, and V wind represents the real-time wind speed, and V rated represents the rated wind speed of the wind turbine, and k wind represents the wind speed influence factor.

[0097] It should be noted that the calculation of the theoretical active power value P new requires clarifying the acquisition methods and calculation logics of each input parameter. For example, the dynamic reactive power change rate ΔQ new is calculated through the time series difference of the reactive power command; the deviation of the wind turbine speed Δω is obtained from the difference between the real-time measured wind turbine speed and the rated speed; the wind speed influence factor k wind is calculated through the ratio of the real-time wind speed to the rated wind speed.

[0098] Furthermore, the dynamic adjustment of each parameter needs to be combined with the operating characteristics of the wind turbine and the real-time state of the power grid. For example, the wind speed influence factor k wind takes the value of 1.0 when the wind speed is close to the rated value; when the wind speed is low or high, the wind speed deviation can be compensated by adjusting the blade angle. The calculation of the dynamic reactive power change rate ΔQ new needs to reduce the adjustment frequency when the change of the power command is relatively smooth, and accelerate the response when the change is large.

[0099] Even further, to enhance the adaptability of the theoretical active power value, the weights of each parameter in the formula can be dynamically adjusted under different operating conditions. For example, in a scenario with significant grid frequency deviation, the weight of Δω can be appropriately increased to enhance the influence of frequency on power; in a scenario with large wind speed fluctuations, by increasing the weight of k wind to quickly respond to wind speed changes.

[0100] The dynamic adjustment of the active power output of the wind turbine described above includes performing a clipping process on the theoretical active power value P new ; using the upper limit of the rated output power P max and the minimum operating power P min of the wind turbine as the power limit boundaries; when P new >P max , adjusting the output power to P max ; when P new <P min , adjusting the output power to P min ; when P min ≤P new ≤P max , keeping P new unchanged; the power value after the clipping process is P limit ;

[0101] Obtain the operating power P of the current wind turbine current and the power value P after clipping processing limit The difference between them is expressed as ΔP = P limit - P current ; Set the adjustment range according to the maximum power change rate R P,max When ΔP > R P,max ·Δt, adjust the power to P current + R P,max ·Δt; When ΔP < -R P,max ·Δt, adjust the power to P current - R P,max ·Δt; When -R P,max ·Δt ≤ ΔP ≤ R P,max ·Δt, keep P limit unchanged, and the result of power adjustment is P smooth ;

[0102] Generate an output power command based on the power adjustment result P smooth ; Send the power adjustment result and the power adjustment rate to the wind turbine control system; Through the control system of the wind turbine, adjust the blade angle, rotational speed and converter operating state; The output power of the adjusted wind turbine is P output ;

[0103] The power adjustment rate is expressed as

[0104]

[0105] It should be noted that the clipping processing for dynamically adjusting the active power output of the wind turbine needs to be combined with the upper and lower limits of the operating power of the wind turbine P max , P min . For example, when the wind speed is high, appropriately increase the power upper limit P max to make full use of wind energy; when the wind speed is low, lower the power lower limit P min to protect the equipment.

[0106] Furthermore, the power smoothing adjustment needs to be dynamically optimized by monitoring the matching of ΔP and R P,max . For example, in a scenario where the wind speed changes smoothly, reduce R P,max to reduce the adjustment amplitude; in a scenario where the wind speed changes violently, increase R P,max to enhance the sensitivity of the adjustment.

[0107] For further illustration, in combination with the real-time monitored wind speed and the operating status of the wind turbine (such as blade angle, rotational speed), the power limit range and adjustment rate are dynamically adjusted. For example, by reducing the influence of rotational speed deviation, the stability of power output is optimized; under complex operating conditions, by dynamically adjusting the limit parameters and power smoothing strategy, the smoothness and safety of the power adjustment process are ensured.

[0108] The two applications of the trend factor serve different control objectives respectively. The first time is used to generate the reactive power command. Through the reactive current adjustment of the grid-side converter, it can quickly respond to the dynamic demands of the power grid and ensure the voltage stability of the power grid. The second time, in combination with the reactive power command and the mechanical characteristic parameters of the wind turbine, it is used to generate the theoretical active power value to achieve the optimized adjustment of the operation of the wind turbine. This design avoids the logical conflict between reactive power adjustment and active power adjustment.

[0109] The first use of the trend factor reflects its sensitivity to the changes in the power grid state, such as voltage fluctuations, frequency offsets, and three-phase unbalances. By dynamically adjusting the reactive current output of the grid-side converter through the trend factor, the reactive power demand in the power grid can be effectively compensated, the voltage fluctuations can be mitigated, and the stability of the power grid can be improved. The priority of reactive power adjustment is based on the service attribute of the wind turbine to the power grid, reflecting the necessity and importance of quick response.

[0110] 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 transfer the result of reactive power adjustment to the optimization of active power, ensuring that the active power adjustment not only meets the demands 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 demands of the power grid and the operating safety and efficiency of the wind turbine.

[0111] The two applications of the trend factor form a design logic of closed-loop control. 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 trend of the power grid. This design ensures a clear hierarchy between reactive power and active power adjustment, and at the same time, through the multi-dimensional application of the trend factor, enhances the overall coordination and stability of the control system.

[0112] The advantages of this design are reflected in the following aspects: First, by using the two applications of the trend factor, the introduction of new calculation indicators is avoided, simplifying the complexity of the control system; second, connecting reactive power adjustment and active power optimization not only meets the real-time demands of the power grid but also takes into account the overall optimization of the operation of the wind turbine; third, through the multiple effects of the trend factor, an efficient interaction mechanism between the power grid state and the operation of the wind turbine is formed, enhancing the dynamic adaptability of the wind turbine and the stability of the power grid.

[0113] Embodiment 2

[0114] Reference Figure 2 , an embodiment of the present invention provides a high-voltage ride-through control system for a wind turbine generator set, including:

[0115] 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;

[0116] The data acquisition module 100 is used to collect three-phase grid voltage signals in real time and preprocess the three-phase voltage signals;

[0117] The state analysis module 200 is used to calculate the voltage fundamental component, the standard deviation of voltage fluctuation, the grid frequency deviation, and the three-phase voltage unbalance degree based on the preprocessed three-phase voltage signals, generate a dynamic state factor, which is used to characterize the dynamic characteristics of the grid in real time, and provide input for subsequent control strategies;

[0118] The trend analysis module 300 is used to generate a trend factor according to the change rate of the dynamic state factor and 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;

[0119] 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, generate a reactive power command, which is used to suppress the increase of the grid voltage, improve the system voltage stability, and feedback the reactive power output result to the active power adjustment link;

[0120] The active power calculation module 500 is used to generate a theoretical active power value according to the trend factor and the reactive power command in combination with the fan mechanical characteristic parameters;

[0121] The power adjustment module 600 is used to generate an output power command for 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 of the wind turbine generator set and the grid adaptability.

[0122] Embodiment 3

[0123] An embodiment of the present invention, which is different from the previous two embodiments, is:

[0124] When the above-mentioned functions are implemented in the form of software function 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, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs that can store program codes.

[0125] media capable of storing program codes.

[0126] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definite sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in conjunction with these instruction execution systems, apparatuses, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0127] More specific examples (non-exhaustive list) of computer-readable media include the following: electrical connection parts with one or more wirings (electronic devices), portable computer disk cartridges (magnetic devices), random access memories (RAMs), read-only memories (ROMs), erasable programmable read-only memories (EPROMs or flash memories), optical fiber devices, and portable compact disc read-only memories (CDROMs). Additionally, a computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other media, then editing, interpreting, or otherwise processing it as necessary, and then storing it in a computer memory.

[0128] It should be understood that each part of the present invention can be implemented by hardware, software, firmware, or a combination thereof. In the above 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, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logic functions on data signals, application specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

[0129] Embodiment 4

[0130] An embodiment of the present invention provides a high voltage ride through control method for a wind turbine. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through simulation experiments.

[0131] The experimental environment is set in a simulated wind farm. The wind turbine connected 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 of the power grid is simulated, and the voltage rapidly rises from 1.0 pu to 1.3 pu and 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. By recording the dynamic changes of the reactive power and active power of the wind turbine, the effect of the control method is verified. The experiment also sets 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.

[0132] The control logic of the traditional method adopts a single voltage feedback regulation method. When the power grid voltage rises, the wind turbine measures the bus voltage value and gradually adjusts the output of the reactive current to provide power grid voltage support. Its technical solution is: collect the power grid voltage signal; generate a reactive current command according to the voltage deviation; adjust the reactive power through the output of the reactive current; the active power is limited by a fixed value and does not actively perform dynamic regulation. This method's adaptability to power grid voltage changes depends on the sensitivity of voltage feedback and fixed control parameters, and does not fully consider the dynamic power grid characteristics.

[0133] The method of the present invention introduces dynamic state factors and trend factors for comprehensive regulation. Its technical solution is as follows: collect three-phase voltage signals of the power grid and perform preprocessing to generate dynamic state factors, and generate trend factors by combining the change rate of the dynamic state factors and the time-series trend index; dynamically adjust the reactive current output of the grid-side converter based on the trend factors to generate a reactive power command; further combine the reactive power command with the mechanical characteristic parameters of the wind turbine to generate a theoretical active power value; finally, dynamically regulate the active power output of the wind turbine through amplitude limiting protection and smooth 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 change of the power grid voltage more quickly and accurately.

[0134] 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, and the experimental results are shown in Table 1.

[0135] Table 1 Comparison table of experimental results

[0136] Index Traditional method 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

[0137] Referring to Table 1, the experimental results show that under the condition of high-voltage ride-through, 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 power grid voltage rises rapidly, extract various parameters such as the fundamental voltage component and the standard deviation of voltage fluctuation through dynamic state factors, and quickly generate the core parameters required for adjustment comprehensively; at the same time, combined with the dynamic prediction ability of the trend factors, the regulation of reactive current can intervene quickly when the high-voltage event just occurs. In contrast, the traditional method completely relies on the gradual feedback of voltage deviation and cannot make effective adjustments before the voltage deviation accumulates to the regulation threshold, resulting in a slow response time and significant hysteresis in power regulation.

[0138] In terms of the volatility of reactive power regulation, the method of the present invention introduces a regulation strategy that combines amplitude limiting protection and smooth adjustment. By restricting the output rate of reactive power, overshoot and large fluctuations during the regulation process are avoided. Especially when the power grid voltage recovers from a high value to the normal value, the method of the present invention can smoothly reduce the reactive power output, thus maintaining the operation stability of the wind turbine and the power grid. In the traditional method, there is no rate limiting mechanism in the regulation process, and obvious overshoot phenomena occur in the reactive power during the power grid voltage recovery stage, further exposing the instability of the traditional control logic in dynamic scenarios.

[0139] 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 fan, and reduces the power fluctuation during the regulation process through dynamic smoothing 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 operation safety of the fan but also avoids the impact on the power grid caused by power fluctuation. The traditional method uses fixed-value limiting in the regulation of active power and fails to make dynamic adjustment according to the real-time power grid state, resulting in significant power fluctuation under high-voltage conditions, showing the problem of insufficient regulation flexibility.

[0140] In terms of steady-state deviation, the present invention comprehensively characterizes the dynamic characteristics of the power grid voltage through the combined application of the dynamic state factor and the trend factor, making the power regulation more accurate. The trend factor predicts the current power grid voltage trend through the time-series weight analysis of historical states, thus effectively reducing the steady-state deviation. The traditional method, due to relying only on a single voltage parameter for regulation, cannot accurately predict the dynamic changes of the power grid state, resulting in a large deviation between the final power regulation result and the target value.

[0141] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A high-voltage ride-through control method for a wind turbine generator set, characterized in that, including: Real-time collect the three-phase voltage signals of the power grid and preprocess the three-phase voltage signals; Calculate the voltage fundamental component, the standard deviation of voltage fluctuation, the power grid frequency deviation, and the three-phase voltage unbalance degree based on the preprocessed three-phase voltage signals, and generate a dynamic state factor; Generate a trend factor according to the change rate of the dynamic state factor and in combination with the time series trend index; According to the trend factor, dynamically adjust the reactive current output through the grid-side converter and generate a reactive power command; Generate a theoretical active power value according to the trend factor and the reactive power command in combination with the wind turbine mechanical characteristic parameters; Generate an output power command for the wind turbine based on the theoretical active power value and dynamically adjust the active power output of the wind turbine; The dynamic state factor is expressed as F dyn = V base + k σ · σ V + k f · Δf + k u · U imbalance Δf = f measured -f rated Among them, V base represents the fundamental component of the three-phase voltage, T represents the sampling period, v a (t), v b (t), v c (t) represent the three-phase instantaneous voltage signals, σ V represents the standard deviation of voltage fluctuation, n represents the total number of sampling points, V i represents the i-th sampled voltage value, represents the average value of the voltage sampling values, Δf represents the power grid frequency offset, f measured represents the power grid frequency measured in real time, f rated represents the rated frequency of the power grid, U imbalance represents the unbalance degree of the three-phase voltage, V a , V b , V c represent the instantaneous amplitudes of the three-phase voltage, k σ , k f , k u represent the gain coefficients, F dyn represents the dynamic state factor; The trend factor is expressed as T trend = ΔF dyn + T index Among them, T trend represents the trend factor, ΔF dyn represents the change rate of the dynamic state factor, T index represents the time series trend index, F dyn,t ,F dyn,t-1 represent the dynamic state factors at the current moment and the previous moment, Δt represents the sampling time interval, w i represents the time series weight factor, F dyn,i represents the dynamic state factor at the i-th moment, L represents the length of the time series; The reactive power command is expressed as Q new = I Q · V bus I Q = k Q · max(0, T trend - T threshold ) Among them, I Q represents the reactive current, Q new represents the reactive power command, T threshold represents the trigger threshold of the trend factor, k Q represents the gain coefficient of the reactive current, V bus represents the bus voltage; The theoretical active power value is expressed as Δω = ω measured -ω rated Among them, P new represents the theoretical active power value, P rated represents the rated active power of the fan, T max represents the maximum value of the trend factor, ΔQ new represents the dynamic reactive power change rate, Q rated represents the rated value of reactive power, Q new,t , Q new,t-1 represents the reactive power at the current and previous moments, Δω represents the fan speed deviation, ω rated represents the rated speed of the fan, Δω max represents the maximum value of the speed deviation, V wind represents the real-time wind speed, V rated represents the rated wind speed of the fan, k wind represents the wind speed influence factor.

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

3. The high-voltage ride-through control method for a wind turbine generator set according to claim 2, characterized in that: The dynamic adjustment of the active power output of the wind turbine includes limiting the theoretical active power value P new ; taking the upper limit of the rated output power P max and the minimum operating power P min of the wind turbine as the power limit boundaries; when P new > P max , adjusting the output power to P max ; when P new < P min , adjusting the output power to P min ; when P min ≤ P new ≤ P max , keeping P new unchanged; the power value after the limiting process is P limit ; Obtain the operating power P of the current wind turbine current and the power value P after clipping processing limit The difference between them is expressed as ΔP = P limit - P current ; Set the adjustment range according to the maximum power change rate R P,max When ΔP > R P,max ·Δt, adjust the power to P current + R P,max ·Δt; When ΔP < - R P,max ·Δt, adjust the power to P current - R P,max ·Δt; When - R P,max ·Δt ≤ ΔP ≤ R P,max ·Δt, keep P limit unchanged, and the result after power adjustment is P smooth ; Based on the power adjustment result P smooth Generate an output power command; send the power adjustment result and the power adjustment rate to the wind turbine control system; adjust the blade angle, rotational speed, and converter operating state through the control system of the wind turbine; the adjusted wind turbine output power is P output ; The power adjustment rate is expressed as 4. A system adopting the high-voltage ride-through control method for a wind turbine unit as described in any one of claims 1 to 3, characterized in that, including: 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 real-time collect the three-phase voltage signals of the power grid and preprocess the three-phase voltage signals; The state analysis module (200) is used to calculate the voltage fundamental component, the standard deviation of voltage fluctuation, the power grid frequency deviation, and the three-phase voltage unbalance degree based on the preprocessed three-phase voltage signals, 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 and in combination with the time series trend index; 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 a reactive power command; The active power calculation module (500) is used to generate a theoretical active power value according to the trend factor and the reactive power command in combination with the wind turbine mechanical characteristic parameters; The power adjustment module (600) is used to generate an output power command for the wind turbine based on the theoretical active power value and dynamically adjust the active power output of the wind turbine.

5. A computer device, comprising a memory and a processor, the memory storing a computer program, characterized in that, When the processor executes the computer program, the steps of the high-voltage ride-through control method for a wind turbine according to any one of claims 1 to ③ are implemented.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, the steps of the high-voltage ride-through control method for a wind turbine according to any one of claims 1 to ③ are implemented.

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