Inertia response method of wind generating set, electronic equipment and medium

Abstract

The invention discloses an inertia response method of a wind generating set, electronic equipment and a medium, and relates to the field of wind power generation. According to the scheme, whether the wind generating set corresponding to a power grid needs to be subjected to inertia response or not is judged according to the current frequency and the current frequency change rate, and after it is judged that the wind generating set needs to be subjected to inertia response, inertia response is conducted; considering the influence of the area where the current wind generating set is located on power control, the rotating speed of a generator of the wind generating set is corrected through the Kalman filtering technology and the current rotating speed of a wind wheel, and the output of the actual torque of the wind generating set is controlled according to the corrected current rotating speed of the generator, the current power and the target power increment. The power control precision of the wind generating set is ensured; secondly, when the wind generating set is switched from the power recovery process to the normal operation mode, the sudden change of the power in the switching process can be reduced by controlling the slope variable quantity of the electromagnetic torque of the wind generating set in the scheme.

Description

Technical Field

[0001] The invention relates to the field of wind power generation, and in particular to an inertia response method, electronic equipment and medium of a wind power generator set. Background Art

[0002] Wind power generation technology is developing rapidly, and the installed capacity of wind turbines is gradually expanding. Large-scale wind turbines are connected to the power grid, so wind turbines are indispensable for supporting the grid frequency, and wind turbine inertia response is an effective method of frequency support.

[0003] In the prior art, although the wind turbine generator set can meet the requirements of response power amplitude and response time, when the wind conditions in the area where the wind turbine generator set is located are relatively severe, the power control accuracy in the inertial response process is easily too large, and the power mutation problem when the wind turbine generator set switches from the power recovery process to the normal operating mode is ignored. Summary of the invention

[0004] The purpose of the present invention is to provide an inertia response method, electronic device and medium for a wind turbine generator set. After determining that the wind turbine generator set needs to perform an inertial response, the scheme takes into account the impact of the current area where the wind turbine generator set is located on power control, so the generator speed of the wind turbine generator set is corrected through the Kalman filtering technology to ensure the power control accuracy of the wind turbine generator set; secondly, when the wind turbine generator set switches from the power recovery process to the normal operating mode, the scheme will control the slope change of the electromagnetic torque of the wind turbine generator set to reduce the sudden change of power during the switching process.

[0005] In order to solve the above technical problems, the present invention provides an inertia response method of a wind turbine generator set, comprising:

[0006] Acquire the current frequency of the power grid and the current frequency change rate of the power grid, and determine whether the wind turbine generator set corresponding to the power grid needs to perform inertial response according to the current frequency and the current frequency change rate;

[0007] If the wind turbine generator set corresponding to the power grid needs to perform an inertial response, the current power, the current generator speed and the current wind rotor speed of the wind turbine generator set are obtained, and the target power increment of the wind turbine generator set is calculated according to the current power and the current generator speed;

[0008] Correcting the current generator speed based on Kalman filtering technology and the current wind rotor speed, and controlling the output of the actual torque of the wind turbine generator set according to the corrected current generator speed, the current power and the target power increment;

[0009] The output of the actual torque is stopped according to the time when the actual torque is output, and the slope change of the electromagnetic torque of the wind turbine generator set is controlled to be a preset slope change until the slope of the electromagnetic torque is reduced to zero.

[0010] Optionally, the correcting the current generator speed based on the Kalman filtering technology and the current wind rotor speed includes:

[0011] Obtaining the low-speed shaft torque, generator torque, equivalent elastic stiffness, damping coefficient and gearbox transmission ratio of the wind turbine generator set;

[0012] Determine a state transfer matrix and an excitation influence matrix according to the equivalent elastic stiffness, the damping coefficient and the gearbox transmission ratio, the current wind rotor speed and the current generator speed;

[0013] Determine a posterior state estimation error according to the equivalent elastic stiffness, the low-speed shaft torque, the generator torque, the state transfer matrix, the excitation influence matrix, the current wind wheel speed and the current generator speed;

[0014] The current generator speed is corrected based on the a posteriori state estimation error.

[0015] Optionally, determining the a posteriori state estimation error according to the equivalent elastic stiffness, the low-speed shaft torque, the generator torque, the state transfer matrix, the excitation influence matrix, the current wind wheel speed and the current generator speed includes:

[0016] Get the current environmental error noise;

[0017] Determine an input vector according to the low-speed shaft torque and the generator torque;

[0018] Determine a state vector according to the equivalent torsion angle of the low-speed shaft of the wind turbine generator set, the current wind rotor speed and the current generator speed;

[0019] Determining an observation vector according to the current generator speed;

[0020] Determine the optimal state estimate value according to the current environmental error noise, the state transfer matrix, the excitation influence matrix, the input vector and the state vector;

[0021] Determine a priori state estimation error based on the state optimal estimation value, the input vector, the state transfer matrix, the excitation influence matrix and a priori state estimation error determination formula;

[0022] The a posteriori state estimation error is determined according to the state transfer matrix, the input vector, the equivalent elastic stiffness, the a priori state estimation error and the observation vector.

[0023] Optionally, determining the a posteriori state estimation error according to the state transfer matrix, the input vector, the equivalent elastic stiffness, the priori state estimation error and the observation vector includes:

[0024] Determine the a priori estimation error covariance corresponding to the a priori state estimation error according to the state transfer matrix, the state optimal error covariance corresponding to the state optimal estimation value, and the preset error noise covariance;

[0025] Determine the Kalman gain according to the prior estimation error covariance and the preset observation matrix;

[0026] The a posteriori state estimation error is determined based on the Kalman gain, the a priori state estimation error, the observation vector, the input vector and the equivalent elastic stiffness.

[0027] Optionally, the correcting the current generator speed based on the a posteriori state estimation error includes:

[0028] The corresponding optimal estimated generator speed is determined according to the a posteriori state estimation error, and the current generator speed is controlled to be converted into the optimal estimated generator speed.

[0029] Optionally, controlling the output of the actual torque of the wind turbine generator set according to the corrected current generator speed, the current power and the target power increment includes:

[0030] Obtaining the rated torque of the PI torque loop of the wind turbine generator set;

[0031] Determine the additional superimposed electromagnetic torque according to the rated torque, the corrected current generator speed, the current power, the target power increment and the additional superimposed electromagnetic torque determination formula;

[0032] The additional superimposed electromagnetic torque is superimposed on the rated torque to control the output of the actual torque of the wind turbine generator set.

[0033] Optionally, before superimposing the additional superimposed electromagnetic torque onto the rated torque, the method further includes:

[0034] Determining an upper limit value of the additional superimposed electromagnetic torque and a lower limit value of the additional superimposed electromagnetic torque according to the rated torque, the corrected current generator speed, the current power, the target power increment and the preset limit value;

[0035] The additional superimposed electromagnetic torque superimposed on the rated torque is controlled not to exceed the upper limit value and the lower limit value.

[0036] Optionally, after stopping the output of the actual torque according to the time of outputting the actual torque, the method further includes:

[0037] Determining, according to the target power increment, a cumulative recovery power value of the wind turbine generator set during the inertial response process;

[0038] The expected value of the generator speed of the wind turbine generator set is determined based on the current generator speed, the accumulated recovery power value and the preset virtual inertia, and the generator speed of the wind turbine generator set is controlled to become the expected value of the generator speed.

[0039] In order to solve the above technical problems, the present invention further provides an electronic device, comprising:

[0040] Memory, used to store computer programs;

[0041] A processor is used to execute the computer program to implement the inertia response method of the wind turbine generator set as described above.

[0042] In order to solve the above technical problem, the present invention further provides a computer-readable storage medium for storing a computer program, wherein the computer program, when executed by a processor, implements the inertia response method of a wind turbine generator set as described above.

[0043] The purpose of the present invention is to provide an inertia response method, electronic device and medium for a wind turbine generator set. This scheme first determines whether the wind turbine generator set corresponding to the power grid needs to perform inertial response based on the current frequency and the current frequency change rate. After determining that the wind turbine generator set needs to perform inertial response, the influence of the current area where the wind turbine generator set is located on power control is taken into consideration. Therefore, the generator speed of the wind turbine generator set is corrected through Kalman filtering technology and the current wind wheel speed, and the actual torque output of the wind turbine generator set is controlled according to the corrected current generator speed, current power and target power increment to ensure the power control accuracy of the wind turbine generator set; secondly, when the wind turbine generator set switches from the power recovery process to the normal operating mode, this scheme will reduce the sudden change of power during the switching process by controlling the slope change of the electromagnetic torque of the wind turbine generator set. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0045] Figure 1 A process flow chart of an inertia response method for a wind turbine generator set provided by the present invention;

[0046] Figure 2 A process flow chart of another inertia response method for a wind turbine generator set provided by the present invention;

[0047] Figure 3 A schematic diagram of a unit inertia response flow based on a Kalman filter provided by the present invention;

[0048] Figure 4 A schematic diagram of a flow chart of a power recovery control process provided by the present invention;

[0049] Figure 5 The present invention provides a schematic structural diagram of an electronic device. DETAILED DESCRIPTION

[0050] The core of the present invention is to provide an inertia response method, electronic device and medium for a wind turbine generator set. After determining that the wind turbine generator set needs to perform an inertial response, this scheme takes into account the impact of the current area where the wind turbine generator set is located on power control, so the generator speed of the wind turbine generator set is corrected through the Kalman filtering technology to ensure the power control accuracy of the wind turbine generator set; secondly, when the wind turbine generator set switches from the power recovery process to the normal operating mode, this scheme will control the slope change of the electromagnetic torque of the wind turbine generator set to reduce the sudden change of power during the switching process.

[0051] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] Please refer to Figure 1 , Figure 1 A process flow chart of an inertia response method for a wind turbine generator set provided by the present invention. The method comprises:

[0053] S11: obtaining the current frequency of the power grid and the current frequency change rate of the power grid, and judging whether the wind turbine generator set corresponding to the power grid needs to perform inertial response according to the current frequency and the current frequency change rate;

[0054] S12: If the wind turbine generator set corresponding to the power grid needs to perform an inertial response, the current power, current generator speed and current wind rotor speed of the wind turbine generator set are obtained, and the target power increment of the wind turbine generator set is calculated according to the current power and the current generator speed;

[0055] S13: correcting the current generator speed based on the Kalman filter technology and the current wind rotor speed, and controlling the output of the actual torque of the wind turbine generator set according to the corrected current generator speed, current power and target power increment;

[0056] S14: stopping the output of the actual torque according to the time of the actual torque output, and controlling the slope change of the electromagnetic torque of the wind turbine generator set to be a preset slope change until the slope of the electromagnetic torque is reduced to zero.

[0057] In the present invention, when the frequency of the power grid fluctuates, the wind turbine generator set needs to output corresponding power to stabilize the frequency fluctuation of the power grid, so it is necessary to obtain the current frequency of the power grid and the current frequency change rate of the power grid in real time, and judge whether the wind turbine generator set corresponding to the power grid needs to perform inertial response according to the current frequency and the current frequency change rate. If the wind turbine generator set needs to perform inertial response, it is necessary to obtain the current power, current generator speed and current wind rotor speed of the wind turbine generator set, and calculate the target power increment of the wind turbine generator set, that is, the power that the wind turbine generator set needs to output for inertial response. However, considering the influence of the current location of the wind turbine generator set on power control, this scheme adopts Kalman filtering technology to calculate the current power increment of the wind turbine generator set according to the current wind rotor speed. The motor speed is corrected to ensure the power control accuracy of the wind turbine generator set; then the actual torque output of the wind turbine generator set is controlled according to the corrected generator speed, current power and target power increment. The above process is the inertial response process of the wind turbine generator set, and when the actual torque output time reaches a certain duration, it is necessary to stop the inertial response of the wind turbine generator set, that is, stop the output of the actual torque of the wind turbine generator set. At this time, when the wind turbine generator set switches from the power recovery process to the normal operating mode, this scheme will control the slope change of the electromagnetic torque of the wind turbine generator set to the preset slope change until the slope of the electromagnetic torque is reduced to zero, that is, smooth the slope change of the electromagnetic torque to reduce the sudden change of power during the switching process, which greatly improves the reliability and stability of the scheme.

[0058] It should be noted that this solution can meet the requirement that the power control accuracy of the wind turbine during the inertial response period is less than 2%Pn; the absolute value of the difference between the minimum power (or maximum power) during the power recovery process and the power before the response is less than 5%Pn, thereby avoiding the impact of a large drop in power during the power recovery process on the power grid; at the same time, smooth control is performed in the process of switching from power recovery exit to normal operating mode to avoid sudden changes in power.

[0059] It should also be noted that the control process of the wind turbine generator set in this scheme can be divided into six steps, such as Figure 2 As shown: S1: Real-time monitoring of grid frequency f, frequency change rate df, generator speed , wind wheel speed Etc. According to whether the grid frequency f and the frequency change rate df exceed the dead zone, it is determined whether inertia response is required.

[0060] S2: If inertia response is required, enter the inertia response control mode and record the initial power , generator speed , calculate the power increment that needs to be supported , enter the inertia response mode, that is, S3

[0061] S3: Enter the inertia response power support control mode to release the rotor kinetic energy stored in the wind turbine to provide power support. By building a speed prediction model, the wind rotor speed is predicted based on the Kalman filter. and generator speed Estimate and calculate the additional electromagnetic torque required by the converter based on the power superposition increment ΔP and the corrected generator speed , reducing the amplitude of power fluctuations during inertia response. Superimposed on the torque control loop of the speed optimal control , get the actual expected torque , to achieve power support.

[0062] S4: The wind turbine generator system determines whether to exit the inertia response mode based on the relationship between the inertia response time (i.e., the actual torque output time) and the preset time threshold. If exited, it enters the power recovery control mode, i.e., S5.

[0063] S5: After exiting the inertia response mode, in order to achieve the power recovery process and meet the requirement that the difference between the minimum power (maximum power) and the initial power is less than 5%Pn, it is necessary to enter the power recovery control mode.

[0064] S6: additional superimposed electromagnetic torque within the preset threshold time 3 Depend on It decreases to 0 with a certain slope, realizing smooth switching from power recovery mode to normal operation mode.

[0065] The present embodiment provides an inertia response method for a wind turbine generator set. The present scheme first determines whether the wind turbine generator set corresponding to the power grid needs to perform an inertial response based on the current frequency and the current frequency change rate. After determining that the wind turbine generator set needs to perform an inertial response, the generator speed of the wind turbine generator set is corrected through Kalman filtering technology and the current wind wheel speed, taking into account the impact of the current wind turbine generator set location on power control. The actual torque output of the wind turbine generator set is controlled based on the corrected current generator speed, current power and target power increment to ensure the power control accuracy of the wind turbine generator set. Secondly, when the wind turbine generator set switches from the power recovery process to the normal operating mode, the present scheme controls the slope change of the electromagnetic torque of the wind turbine generator set to reduce the sudden change of power during the switching process.

[0066] Based on the above embodiments:

[0067] As an optional embodiment, the current generator speed is corrected based on the Kalman filter technology and the current wind rotor speed, including:

[0068] Obtain the low-speed shaft torque, generator torque, equivalent elastic stiffness, damping coefficient and gearbox transmission ratio of the wind turbine generator set;

[0069] Determine the state transfer matrix and the excitation influence matrix according to the equivalent elastic stiffness, the damping coefficient and the gearbox transmission ratio, the current wind rotor speed and the current generator speed;

[0070] Determine the a posteriori state estimation error according to the equivalent elastic stiffness, the low-speed shaft torque, the generator torque, the state transfer matrix, the excitation influence matrix, the current wind wheel speed and the current generator speed;

[0071] The current generator speed is corrected based on the a posteriori state estimation error.

[0072] In the present invention, because the current generator speed needs to be corrected according to the Kalman filtering technology, it is necessary to first obtain the low-speed shaft torque, generator torque, equivalent elastic stiffness, damping coefficient and gearbox transmission ratio of the wind turbine generator set, and then determine the state transfer matrix and the excitation influence matrix respectively, and then determine the a posteriori state estimation error based on the above-mentioned determined parameters and the current generator speed, and finally correct the current generator speed based on the a posteriori state estimation error. This scheme takes into account the influence of the current wind turbine generator set in the area where the wind turbine generator set is located on power control, and adopts the Kalman filtering technology to correct the current generator speed of the wind turbine generator set, thereby ensuring the accuracy of power control of the wind turbine generator set.

[0073] It should be noted that the unit inertia response process based on the Kalman filter is as follows: Figure 3 As shown, the inertia response power support control specifically includes:

[0074] S3.1: Construct the prediction model of wind rotor speed and generator speed:

[0075] ;

[0076] Select the state estimate vector ,in is the wind wheel speed, is the generator speed, is the equivalent torsion angle of the low-speed shaft, is the state quantity at time k; select the input vector , where T is the low speed shaft torque, is the generator torque, is the input quantity at time k; select the observation vector , is the observed quantity at time k; is the model error noise at time k-1 (current environment error noise), is the measurement error noise at time k, which satisfies Gaussian white noise; D is the preset equivalent elastic stiffness; A is the state transfer matrix, B is the excitation influence matrix, and H is the observation matrix, which respectively satisfy the following relationships:

[0077] ;

[0078] ;

[0079] ;

[0080] in , is the equivalent elastic stiffness and damping coefficient of the unit transmission system, , are the wind wheel speed and generator speed, and G is the gearbox transmission ratio.

[0081] S3.2: Based on the optimal estimate of the state at time k-1 , the prior estimate of time k and the prior estimate error covariance To update:

[0082] ;

[0083] ;

[0084] in is the prior state estimation error at time k, , is the true value of the state at time k, Q is the covariance of the model error noise, T represents the transposition, is the state optimal estimation error covariance.

[0085] S3.3: Prior state estimation based on k-time observations Correction is performed to obtain the posterior state estimation error , that is, the optimal estimate of the system at time k:

[0086] ;

[0087] in and is the Kalman gain, i.e. the weighting matrix. The posterior state estimation error Variance as follows:

[0088] ;

[0089] S3.4: Kalman gain Take a value so that the objective function Variance Minimum, get the optimal estimate of the state variable x at time k , I and R are preset variance calculation parameters. That is, the state estimate and its variance are updated using the following updated state equation:

[0090] ;

[0091] ;

[0092] ;

[0093] S3.5: At each moment, the state quantity x is iterated, updated, and estimated by the above steps, where the generator speed at moment k is optimally estimated. The generator speed is .use , initial power before response , and the power increment , calculate the additional superimposed electromagnetic torque for power response , in order to reduce the speed measurement error in bad wind conditions and improve the power control accuracy:

[0094] ;

[0095] in is the rated torque of the wind turbine PI torque loop. Additional electromagnetic torque superimposed on the foundation The power support of inertia response can be achieved.

[0096] As an optional embodiment, determining the posterior state estimation error according to the equivalent elastic stiffness, the low-speed shaft torque, the generator torque, the state transfer matrix, the excitation influence matrix, the current wind wheel speed and the current generator speed includes:

[0097] Get the current environmental error noise;

[0098] Determine the input vector according to the low-speed shaft torque and the generator torque;

[0099] Determine the state vector according to the equivalent torsion angle of the low-speed shaft of the wind turbine generator set, the current wind rotor speed and the current generator speed;

[0100] Determine the observation vector according to the current generator speed;

[0101] Determine the optimal state estimate value according to the current environmental error noise, state transfer matrix, excitation influence matrix, input vector and state vector;

[0102] Determine the prior state estimation error based on the state optimal estimation value, the input vector, the state transfer matrix, the excitation influence matrix and the prior state estimation error determination formula;

[0103] The a posteriori state estimation error is determined based on the state transfer matrix, the input vector, the equivalent elastic stiffness, the a priori state estimation error and the observation vector.

[0104] In the present invention, the specific process of determining the a posteriori state estimation error actually needs to take into account the influence of environmental error noise on the power output of the wind turbine generator set. Therefore, the current environmental error noise is first obtained, and then the input vector is determined according to the low-speed shaft torque and the generator torque. The state vector is determined according to the equivalent torsion angle of the low-speed shaft of the wind turbine generator set, the current wind wheel speed and the current generator speed. The observation vector is determined according to the current generator speed, and the state optimal estimate is determined based on the above-determined vectors and the current environmental error noise. The state optimal estimate is then substituted into the a priori state estimation error determination formula to determine the a priori state estimation error. Finally, the a posteriori state estimation error can be determined according to the state transfer matrix, the input vector, the equivalent elastic stiffness, the a priori state estimation error and the observation vector, thereby eliminating the influence of environmental noise in the process of determining the a posteriori state estimation error and improving the accuracy of the scheme.

[0105] As an optional embodiment, determining the a posteriori state estimation error according to the state transfer matrix, the input vector, the equivalent elastic stiffness, the a priori state estimation error and the observation vector includes:

[0106] Determine the prior estimation error covariance corresponding to the prior state estimation error according to the state transfer matrix, the state optimal error covariance corresponding to the state optimal estimation value, and the preset error noise covariance;

[0107] Determine the Kalman gain based on the prior estimation error covariance and the preset observation matrix;

[0108] The a posteriori state estimation error is determined based on the Kalman gain, the a priori state estimation error, the observation vector, the input vector and the equivalent elastic stiffness.

[0109] In the present invention, the specific process of determining the a priori state estimation error according to the state transfer matrix, input vector, equivalent elastic stiffness, a priori state estimation error and observation vector is as follows: in order to determine the a priori state estimation error, it is necessary to first determine the Kalman gain in the Kalman filtering technology, and the Kalman gain needs to first determine the a priori estimation error covariance corresponding to the a priori state estimation error, so it is necessary to first determine the a priori estimation error covariance according to the state transfer matrix, the state optimal error covariance corresponding to the state optimal estimate value, and the preset error noise covariance, and then determine the Kalman gain according to the a priori estimation error covariance and the preset observation matrix, and finally determine the a priori state estimation error based on the determined Kalman gain, a priori state estimation error, observation vector, input vector and equivalent elastic stiffness, and the process of determining the a priori state estimation error is a Kalman filtering, so the determined a priori state estimation error is more accurate, which is convenient for power control of the wind turbine.

[0110] As an optional embodiment, the current generator speed is corrected based on the a posteriori state estimation error, including:

[0111] The corresponding optimal estimated generator speed is determined according to the a posteriori state estimation error, and the current generator speed is controlled to be converted into the optimal estimated generator speed.

[0112] In the present invention, considering that the generator speed has a corresponding relationship with the state estimation error, after determining the a posteriori state estimation error, the corresponding optimal estimated generator speed can be obtained according to the corresponding relationship, and the current generator speed needs to be controlled to be converted into the optimal estimated generator speed to complete the correction of the generator speed, thereby ensuring the integrity of the scheme.

[0113] As an optional embodiment, controlling the output of the actual torque of the wind turbine generator set according to the corrected current generator speed, current power and target power increment includes:

[0114] Obtain the rated torque of the PI torque loop of the wind turbine generator set;

[0115] Determine the additional superimposed electromagnetic torque according to the rated torque, the corrected current generator speed, the current power, the target power increment and the additional superimposed electromagnetic torque determination formula;

[0116] The additional superimposed electromagnetic torque is superimposed on the rated torque to control the output of the actual torque of the wind turbine generator set.

[0117] In the present invention, the specific process of controlling the output of the actual torque of the wind generator set according to the corrected current generator speed, current power and target power increment is as follows: considering that the actual torque of the wind generator set is composed of the rated torque and the additional superimposed electromagnetic torque, it is necessary to first obtain the rated torque of the PI torque loop of the wind generator set, and then substitute the determined rated torque, the corrected current generator speed, the current power and the target power increment into the additional superimposed electromagnetic torque determination formula to determine the additional superimposed electromagnetic torque, and then superimpose the additional superimposed electromagnetic torque on the rated torque to control the output of the actual torque of the wind generator set. Because the additional superimposed electromagnetic torque in this scheme is determined by the corrected current generator speed, the obtained additional superimposed electromagnetic torque is more accurate, so that the output of the actual torque of the wind generator is more accurate.

[0118] As an optional embodiment, before the additional superimposed electromagnetic torque is superimposed on the rated torque, the method further includes:

[0119] Determine the upper limit value of the additional superimposed electromagnetic torque and the lower limit value of the additional superimposed electromagnetic torque according to the rated torque, the corrected current generator speed, the current power, the target power increment and the preset limit value;

[0120] The additional superimposed electromagnetic torque added to the rated torque is controlled not to exceed the upper and lower limits.

[0121] In the present invention, before the additional superimposed electromagnetic torque is superimposed on the rated torque, taking into account the power limitation of the power recovery process of the wind turbine generator set, it is necessary to first determine the upper limit value of the additional superimposed electromagnetic torque and the lower limit value of the additional superimposed electromagnetic torque based on the rated torque, the corrected current generator speed, the current power, the target power increment and the preset limit value, and then ensure that the additional superimposed electromagnetic torque superimposed on the rated torque does not exceed the upper limit value and the lower limit value, so as to prevent the power from exceeding the limit requirements, thereby improving the reliability of the scheme.

[0122] As an optional embodiment, after the output of the actual torque is stopped according to the time of the actual torque output, the method further includes:

[0123] Determine the cumulative recovery power value of the wind turbine generator set during the inertial response process according to the target power increment;

[0124] The expected value of the generator speed of the wind turbine generator set is determined based on the current generator speed, the accumulated recovery power value and the preset virtual inertia, and the generator speed of the wind turbine generator set is controlled to become the expected value of the generator speed.

[0125] In the present invention, it is considered that during the power recovery process of the wind turbine generator set, the speed recovery rate is likely to be too fast, resulting in a large overshoot of the speed, causing speed oscillation, resulting in power oscillation, so that the power exceeds the limit during the power recovery process. Therefore, after stopping the output of the actual torque according to the actual torque output time, that is, during the power recovery process, the cumulative recovery power value of the wind turbine generator set in the inertial response process is first determined according to the target power increment, and then the expected value of the generator speed of the wind turbine generator set is determined based on the determined current generator speed, the cumulative recovery power value and the preset virtual inertia, and the generator speed of the wind turbine generator set is controlled to become the expected value of the generator speed, that is, the generator speed is controlled to meet the expected value of the speed within the power limit, so as to avoid power oscillation caused by the wind turbine generator set during the power recovery process, and even cause safety problems.

[0126] It should be noted that according to the initial speed given value and the real-time speed, the speed set point is modified, the expected value of the generator speed is calculated, the speed is restored, and the power recovery rate is limited to reduce the overshoot during the power recovery process and avoid excessive power overshoot, which causes the power to exceed the limit requirement. In order to avoid the speed recovery rate being too fast during the recovery process, resulting in a large overshoot of the speed, causing speed oscillation, resulting in power oscillation, and causing the power to exceed the limit requirement during the recovery process. The power recovery rate changes with a certain slope, and the flow of the power recovery control process is as follows: Figure 4 shown.

[0127] Expected generator speed Solve according to the following formula:

[0128] ;

[0129] Where J is the virtual inertia, is the cumulative restored power value.

[0130] According to the real-time speed , the rated torque of the original torque control loop of the wind turbine generator set , initial power (current power), calculate the additional superimposed electromagnetic torque required during the recovery process and its upper and lower limits, meeting the power requirements during the recovery process.

[0131] Among them, during the power recovery process, the additional superimposed electromagnetic torque Superimposed torque at the end of inertia response A certain slope changes slowly to 0. Limit value Used to set the upper and lower limits of power to avoid power exceeding the limit requirements and additional superimposed torque Upper and lower limits ( , ) as follows:

[0132] ;

[0133] ;

[0134] );

[0135] According to the power recovery time and the preset time threshold, determine whether to exit the power recovery control mode. If exiting the power recovery control mode, record the additional superimposed electromagnetic torque at this time. , enter the power smooth switching control mode.

[0136] It should also be noted that during the power smooth switching process, The change slope limit is as follows, and its initial value is .

[0137] ;

[0138] ;

[0139] in, It is the additional electromagnetic torque value superimposed during the power smooth switching process at the previous moment. is the preset electromagnetic torque.

[0140] Please refer to Figure 5 , Figure 5 A schematic diagram of the structure of an electronic device provided by the present invention. The electronic device comprises:

[0141] A memory 20, for storing computer programs;

[0142] The processor 21 is used to execute a computer program to implement the inertia response method of the wind turbine generator set as described above.

[0143] The electronic device provided in this embodiment may include but is not limited to a smart phone, a tablet computer, a laptop computer or a desktop computer.

[0144] Among them, the processor 21 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 21 can be implemented in at least one hardware form of a digital signal processor (DSP), a field-programmable gate array (FPGA), and a programmable logic array (PLA). The processor 21 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a central processing unit (CPU); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 21 may be integrated with a graphics processing unit (GPU), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 21 may also include an artificial intelligence (AI) processor, which is used to process computing operations related to machine learning.

[0145] The memory 20 may include one or more computer-readable storage media, which may be non-transitory. The memory 20 may also include a high-speed random access memory, and a non-volatile memory, such as one or more disk storage devices, flash memory storage devices. In this embodiment, the memory 20 is at least used to store the following computer program 201, wherein, after the computer program is loaded and executed by the processor 21, it can implement the relevant steps of the inertia response method of the wind turbine generator set disclosed in any of the aforementioned embodiments. In addition, the resources stored in the memory 20 may also include an operating system 202 and data 203, etc., and the storage method may be temporary storage or permanent storage. Among them, the operating system 202 may include Windows, Unix, Linux, etc. Data 203 may include, but is not limited to, the inertia response method of the wind turbine generator set, etc.

[0146] In some embodiments, the electronic device may further include a display screen 22 , an input / output interface 23 , a communication interface 24 , a power source 25 , and a communication bus 26 .

[0147] Those skilled in the art will understand that Figure 5 The structure shown in the figure does not constitute a limitation on the electronic device, and may include more or fewer components than shown in the figure.

[0148] The purpose of this embodiment is to provide an electronic device, in which the memory 20 is used to store computer programs, and the processor 21 is used to implement the steps of the inertia response method of the wind turbine generator set when executing the computer program, so as to make the control process more efficient and accurate.

[0149] The present invention also provides an embodiment corresponding to a computer-readable storage medium, which is used to store a computer program, and when the computer program is executed by a processor, the inertia response method of the wind turbine generator set as described above is implemented.

[0150] It is understandable that if the method in the above embodiment is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium to execute all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk and other media that can store program codes.

[0151] The computer-readable storage medium provided in this embodiment corresponds to the above method, and therefore has the same beneficial effects as the above method. Therefore, for the embodiments of the computer-readable storage medium part, please refer to the description of the embodiments of the method part, which will not be repeated here.

[0152] It should be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0153] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for inertia response of a wind turbine generator set, characterized in that: include: Acquire the current frequency of the power grid and the current frequency change rate of the power grid, and determine whether the wind turbine generator set corresponding to the power grid needs to perform inertial response according to the current frequency and the current frequency change rate; If the wind turbine generator set corresponding to the power grid needs to perform an inertial response, the current power, the current generator speed and the current wind rotor speed of the wind turbine generator set are obtained, and the target power increment of the wind turbine generator set is calculated according to the current power and the current generator speed; Correcting the current generator speed based on Kalman filtering technology and the current wind rotor speed, and controlling the output of the actual torque of the wind turbine generator set according to the corrected current generator speed, the current power and the target power increment; The output of the actual torque is stopped according to the time when the actual torque is output, and the slope change of the electromagnetic torque of the wind turbine generator set is controlled to be a preset slope change until the slope of the electromagnetic torque is reduced to zero.

2. The inertia response method of a wind turbine generator set according to claim 1, characterized in that: The correcting the current generator speed based on the Kalman filtering technology and the current wind rotor speed includes: Obtaining the low-speed shaft torque, generator torque, equivalent elastic stiffness, damping coefficient and gearbox transmission ratio of the wind turbine generator set; Determine a state transfer matrix and an excitation influence matrix according to the equivalent elastic stiffness, the damping coefficient and the gearbox transmission ratio, the current wind rotor speed and the current generator speed; Determine a posterior state estimation error according to the equivalent elastic stiffness, the low-speed shaft torque, the generator torque, the state transfer matrix, the excitation influence matrix, the current wind wheel speed and the current generator speed; The current generator speed is corrected based on the a posteriori state estimation error.

3. The inertia response method of a wind turbine generator set according to claim 2, characterized in that: The determining of the a posteriori state estimation error according to the equivalent elastic stiffness, the low-speed shaft torque, the generator torque, the state transfer matrix, the excitation influence matrix, the current wind wheel speed and the current generator speed comprises: Get the current environmental error noise; Determine an input vector according to the low-speed shaft torque and the generator torque; Determine a state vector according to the equivalent torsion angle of the low-speed shaft of the wind turbine generator set, the current wind rotor speed and the current generator speed; Determining an observation vector according to the current generator speed; Determine the optimal state estimate value according to the current environmental error noise, the state transfer matrix, the excitation influence matrix, the input vector and the state vector; Determine a priori state estimation error based on the state optimal estimation value, the input vector, the state transfer matrix, the excitation influence matrix and a priori state estimation error determination formula; The a posteriori state estimation error is determined according to the state transfer matrix, the input vector, the equivalent elastic stiffness, the a priori state estimation error and the observation vector.

4. The inertia response method of a wind turbine generator set according to claim 3, characterized in that: The determining the a posteriori state estimation error according to the state transfer matrix, the input vector, the equivalent elastic stiffness, the a priori state estimation error and the observation vector comprises: Determine the a priori estimation error covariance corresponding to the a priori state estimation error according to the state transfer matrix, the state optimal error covariance corresponding to the state optimal estimation value, and the preset error noise covariance; Determine the Kalman gain according to the prior estimation error covariance and a preset observation matrix; The a posteriori state estimation error is determined based on the Kalman gain, the a priori state estimation error, the observation vector, the input vector and the equivalent elastic stiffness.

5. The inertia response method of a wind turbine generator set according to claim 2, characterized in that: The correcting the current generator speed based on the a posteriori state estimation error includes: The corresponding optimal estimated generator speed is determined according to the a posteriori state estimation error, and the current generator speed is controlled to be converted into the optimal estimated generator speed.

6. The inertia response method of a wind turbine generator set according to any one of claims 1 to 5, characterized in that: The controlling the output of the actual torque of the wind turbine generator set according to the corrected current generator speed, the current power and the target power increment comprises: Obtaining the rated torque of the PI torque loop of the wind turbine generator set; Determine the additional superimposed electromagnetic torque according to the rated torque, the corrected current generator speed, the current power, the target power increment and the additional superimposed electromagnetic torque determination formula; The additional superimposed electromagnetic torque is superimposed on the rated torque to control the output of the actual torque of the wind turbine generator set.

7. The inertia response method of a wind turbine generator set according to claim 6, characterized in that: Before the additional superimposed electromagnetic torque is superimposed on the rated torque, the method further includes: Determining an upper limit value of the additional superimposed electromagnetic torque and a lower limit value of the additional superimposed electromagnetic torque according to the rated torque, the corrected current generator speed, the current power, the target power increment and the preset limit value; The additional superimposed electromagnetic torque superimposed on the rated torque is controlled not to exceed the upper limit value and the lower limit value.

8. The inertia response method of a wind turbine generator set according to claim 6, characterized in that: After stopping the output of the actual torque according to the time of outputting the actual torque, the method further comprises: Determining, according to the target power increment, a cumulative recovery power value of the wind turbine generator set during the inertial response process; The expected value of the generator speed of the wind turbine generator set is determined based on the current generator speed, the accumulated recovery power value and the preset virtual inertia, and the generator speed of the wind turbine generator set is controlled to become the expected value of the generator speed.

9. An electronic device, characterized in that: include: Memory, used to store computer programs; A processor is used to execute the computer program to implement the inertia response method of a wind turbine generator set according to any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that: Used to store a computer program, which, when executed by a processor, implements the inertia response method of a wind turbine generator set according to any one of claims 1 to 8.

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