Transmission shaft system torsional vibration suppression method and system for grid-connected wind turbine generator

Abstract

This invention provides a method for suppressing torsional vibration of the shaft system of a grid-connected wind turbine, comprising: Step S1: Real-time acquisition of the wind turbine's rotational speed to obtain the generator angular velocity; Step S2: Inputting the generator angular velocity into a virtual phase angle damping controller; The phase angle damping controller extracts the oscillation component from the generator angular velocity of the wind turbine and calculates a virtual phase angle compensation amount; Step S3: Superimposing the virtual phase angle compensation amount onto the synchronous phase angle output by the grid-connected control technology, thereby suppressing the torsional vibration of the wind turbine shaft system. The method proposed in this invention uses the generator rotational speed as the input quantity, and the virtual phase angle damping controller generates a phase angle compensation amount θ. comp Synchronous phase angle θ generated by network control technology syn Superposition enables the suppression of shaft torsional vibration, no longer limited by the bandwidth of grid-type control technology, and can effectively suppress the shaft torsional vibration of wind turbines caused by the application of grid-type control technology.

Description

Technical Field

[0001] This invention belongs to the field of wind power generation control technology, specifically relating to a method and system for suppressing torsional vibration in the drive shaft system of a grid-connected wind turbine. More specifically, it is a method for suppressing torsional vibration in the drive shaft system of a grid-connected wind turbine based on virtual phase angle compensation. Background Technology

[0002] With the rapid development of power systems towards a high proportion of new energy sources and power electronics, problems such as reduced grid inertia, weakened grid strength, and decreased frequency regulation capability are becoming increasingly prominent. Grid-based control technologies, represented by virtual synchronous machine control, have received widespread attention from academia and industry in recent years because they enable wind turbines to simulate synchronous machine characteristics, operate stably under weak grid conditions, and actively provide inertial response to grid frequency changes, thus damping these changes. While wind turbines using grid-based control technology can effectively improve grid friendliness, they also strengthen the coupling between the turbine's front end and the grid, making grid-side disturbances more likely to trigger torsional vibrations in the turbine's drive shaft system, increasing the failure frequency of the drive shaft system and causing unnecessary economic losses.

[0003] To address the shaft torsional vibration problem of wind turbine generators, patent document CN107017647A uses an additional damping controller to generate a compensation amount based on the instantaneous torsional angular velocity difference of the transmission shaft of a doubly fed wind turbine generator, which is then superimposed on the DC voltage command value of the grid-side converter. The method aims to suppress shaft torsional vibration by leveraging the relationship between DC voltage, electromagnetic torque, and system active power. However, this method has not achieved the expected effect of suppressing shaft torsional vibration.

[0004] Patent document CN117767345A proposes a method to suppress shaft torsional vibration of wind turbine units by using a bandpass filter to extract the low-frequency component of generator speed and generating an active power compensation value that is superimposed on the active power command value of the power outer loop. However, this method explicitly proposes to use a PI controller to control the active power, which belongs to grid-based control technology. It does not analyze the shaft torsional vibration problem of wind turbine units based on grid-based control technology.

[0005] Patent document CN116581778A presents an analysis method for the influence of virtual synchronous machine control on the torsional vibration of the turbine shaft system based on complex torque analysis. It points out that the torsional vibration problem of the shaft system of grid-connected wind turbines is more prominent than that of grid-connected wind turbines, but does not provide an effective strategy for suppressing the torsional vibration of the shaft system. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method and system for suppressing torsional vibration in the drive shaft system of a grid-type wind turbine.

[0007] A method for suppressing torsional vibration of the shaft system of a grid-type wind turbine provided by the present invention includes:

[0008] Step S1: Real-time acquisition of wind turbine rotation speed to obtain generator angular velocity;

[0009] Step S2: Input the generator angular velocity into the virtual phase angle damping controller; the phase angle damping controller extracts the oscillation component in the generator angular velocity of the wind turbine and calculates the virtual phase angle compensation amount;

[0010] Step S3: The virtual phase angle compensation is superimposed on the synchronous phase angle output by the grid-type control technology to suppress the torsional vibration of the wind turbine shaft system.

[0011] Preferably, in step S1, the wind turbine generator includes: a doubly fed wind turbine generator and a permanent magnet wind turbine generator;

[0012] The natural oscillation frequency of the wind turbine's shaft system is mathematically expressed as follows:

[0013]

[0014] Where, ω n H is the natural oscillation frequency of the shaft system. w H g These are the inertial time constants of the wind turbine and the generator, respectively; K s ω is the equivalent stiffness coefficient of the transmission shaft system. b This is the reference value for angular velocity.

[0015] In step S2, the virtual phase angle damping controller is used to extract the oscillation component in the generator angular velocity;

[0016] The virtual phase angle damping controller includes: a bandpass filter and a PI controller; the PI controller is connected to the bandpass filter;

[0017] The transfer function of the virtual phase angle damping controller is expressed mathematically as follows:

[0018]

[0019] Among them, G VADC Here is the transfer function of the virtual phase angle damped controller, where G is the gain coefficient; ω c The characteristic frequency of the bandpass filter is ω, which is the natural oscillation frequency of the unit's drive shaft system. n Decide; K is the damping ratio of the bandpass filter. cp K ci , respectively, are the proportional coefficient and integral coefficient of the PI controller; s is the differential operator in the complex field.

[0020] Preferably, the virtual phase angle compensation amount is expressed mathematically as follows:

[0021] θ comp =G VADC ω G

[0022] Where, θ comp This represents the virtual phase angle compensation amount; the ω G This represents the generator's angular velocity.

[0023] Preferably, in step S3, the synchronization phase angle is obtained through a virtual synchronizer;

[0024] The control function of the virtual synchronizer is expressed mathematically as follows:

[0025]

[0026] Among them, H vsg D is the inertial time constant of the virtual synchronizer. vsg ω is the damping coefficient of the virtual synchronous machine. syn θ is the angular frequency generated by the virtual synchronizer. syn Generate the phase angle for the virtual synchronizer; ω g P is the angular frequency of the power grid. eref This is the active power command value; G P-θ Generate the transfer function for the phase angle of the virtual synchronizer; ω b ω is the reference value for angular velocity; s is the differential operator in the complex field; P e This is the measured value of active power.

[0027] A shaft torsional vibration suppression system for a grid-type wind turbine provided by the present invention includes:

[0028] Module M1: Real-time acquisition of wind turbine rotation speed to obtain generator angular velocity;

[0029] Module M2: Inputs the generator angular velocity into the virtual phase angle damping controller; the phase angle damping controller extracts the oscillation component in the generator angular velocity of the wind turbine and calculates the virtual phase angle compensation amount;

[0030] Module M3: The virtual phase angle compensation is superimposed on the synchronous phase angle output by the grid-type control technology, thereby suppressing the torsional vibration of the wind turbine shaft system.

[0031] Preferably, in module M1, the wind turbine generator includes: a doubly fed wind turbine generator and a permanent magnet wind turbine generator;

[0032] The natural oscillation frequency of the wind turbine's shaft system is mathematically expressed as follows:

[0033]

[0034] Where, ω n H is the natural oscillation frequency of the shaft system. w H g These are the inertial time constants of the wind turbine and the generator, respectively; K s ω is the equivalent stiffness coefficient of the transmission shaft system. b This is the reference value for angular velocity;

[0035] In module M2, the virtual phase angle damping controller is used to extract the oscillation component in the generator angular velocity;

[0036] The virtual phase angle damping controller includes: a bandpass filter and a PI controller; the PI controller is connected to the bandpass filter;

[0037] The transfer function of the virtual phase angle damping controller is expressed mathematically as follows:

[0038]

[0039] Among them, G VADC Here is the transfer function of the virtual phase angle damped controller, where G is the gain coefficient; ω c The characteristic frequency of the bandpass filter is ω, which is the natural oscillation frequency of the unit's drive shaft system. n Decide; K is the damping ratio of the bandpass filter. cp K ci , respectively, are the proportional coefficient and integral coefficient of the PI controller; s is the differential operator in the complex field.

[0040] Preferably, the virtual phase angle compensation amount is expressed mathematically as follows:

[0041] θ comp =G VADC ω G

[0042] Where, θ comp This represents the virtual phase angle compensation amount; the ω G This represents the generator's angular velocity.

[0043] Preferably, in module M3, the synchronization phase angle is obtained through a virtual synchronizer;

[0044] The control function of the virtual synchronizer is expressed mathematically as follows:

[0045]

[0046] Among them, G vsg D is the inertial time constant of the virtual synchronizer. vsgω is the damping coefficient of the virtual synchronous machine. syn θ is the angular frequency generated by the virtual synchronizer. syn Generate the phase angle for the virtual synchronizer; ω g P is the angular frequency of the power grid. eref This is the active power command value; G P-θ Generate the transfer function for the phase angle of the virtual synchronizer; ω b ω is the reference value for angular velocity; s is the differential operator in the complex field; P e This is the measured value of active power.

[0047] A computer-readable storage medium storing a computer program, characterized in that, when the computer program is executed by a processor, it implements the steps of the method for suppressing torsional vibration of the grid-type wind turbine shaft system.

[0048] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the computer program, when executed by the processor, implements the steps of the method for suppressing torsional vibration of the grid-type wind turbine shaft system.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] 1. This invention uses the generator speed as the input, and the phase angle compensation generated by the virtual phase angle damping controller is superimposed with the synchronous phase angle generated by the grid-type control technology to suppress shaft torsional vibration;

[0051] 2. This invention is no longer limited by the bandwidth of grid-type control technology and can effectively suppress the torsional vibration of the wind turbine shaft system caused by the application of grid-type control technology.

[0052] 3. This invention analyzes the torsional vibration problem of wind turbine shaft system based on grid-type control technology, effectively controls the impact of grid-side disturbances on the torsional vibration characteristics of wind turbine shaft system, and thus reduces the failure frequency of the unit's drive shaft system. Attached Figure Description

[0053] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0054] Figure 1 A schematic diagram of the grid-type control technology that takes into account the proposed shaft torsional vibration suppression strategy provided by the present invention;

[0055] Figure 2 Bode plot of the transfer function of electromagnetic torque obtained from generator speed under the influence of the network-type control loop provided by the present invention;

[0056] Figure 3A comparison diagram of the torsional vibration suppression effect of the existing shaft torsional vibration suppression strategy provided by the present invention under grid-type control;

[0057] Figure 4 A schematic diagram of a grid-connected doubly-fed wind turbine connected to an infinite power grid provided by the present invention;

[0058] Figure 5 This is a comparison diagram showing the torsional vibration suppression effect of the proposed shaft system torsional vibration suppression strategy under grid-type control. Detailed Implementation

[0059] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0060] Existing shaft torsional vibration suppression strategies for wind turbines achieve rapid suppression of shaft torsional vibration. Taking the shaft torsional vibration suppression strategies provided in patent documents CN117767345A and CN118327887A as examples, these strategies extract the oscillation component of the generator speed during shaft torsional vibration and generate a compensation amount that is superimposed on the electromagnetic torque. This creates a component in the electromagnetic torque that has the same frequency and phase as the generator speed oscillation component. Then, as the generator speed increases / decreases, the corresponding component in the electromagnetic torque is actively increased / decreased, providing a resistance torque to the generator speed oscillation component, thereby achieving rapid suppression of shaft torsional vibration.

[0061] Therefore, the prerequisite for the above-mentioned shaft torsional vibration suppression strategy to be effective is that the control strategy adopted by the converter has a fast response speed, ensuring that the generator speed and electromagnetic torque components are in phase or have only a small difference in the natural oscillation frequency band of the shaft. Specifically, in grid-connected wind turbines, due to the large control bandwidth of grid-connected control technology, the wind turbine has a fast response speed to the active power / electromagnetic torque command value, resulting in a small phase difference between the electromagnetic torque and the generator speed in the natural oscillation frequency band of the shaft. Therefore, by using the strategy proposed in existing literature and superimposing a compensation amount on the electromagnetic torque command value, the torsional vibration of the shaft can be quickly suppressed without being affected by the control loop, when the electromagnetic torque generates a component with the same frequency and phase as the generator speed oscillation component.

[0062] However, in wind turbines based on grid-type control, to simulate the characteristics of a synchronous generator, the time scale of the dynamics of the power angle and frequency, dominated by active power-frequency control, is on the order of seconds. This limits the ability of the aforementioned shaft torsional vibration suppression strategy to effectively suppress shaft torsional vibration under grid-type control.

[0063] like Figure 2 As shown, the slower dynamic characteristics of the network-type control cause a phase difference between the electromagnetic torque and the generator speed in the natural oscillation frequency band of the shaft system, and also affect the enhanced inertial response capability of the random group, i.e., H. vsg As the speed increases, the phase difference between the generator speed and the electromagnetic torque will exceed 90°. If the existing shaft torsional vibration suppression strategy is still used, and the compensation is superimposed on the active power / electromagnetic torque command value, the existing shaft torsional vibration suppression strategy, which only increases the amplitude of the component of the electromagnetic torque in the shaft's inherent oscillation frequency band without correcting the phase difference between it and the generator speed, will actively decrease / increase the electromagnetic torque when the generator speed increases / decreases, providing power torque to the generator speed oscillation component, further deteriorating the shaft torsional vibration characteristics and amplifying the shaft torsional vibration, i.e., amplifying the technical problem.

[0064] Although, for example, patent document CN116581778A discloses an analysis method for the influence of grid-type control technology based on complex torque coefficient method on the torsional vibration of the generator shaft system, its complex torque coefficient method only shows the influence of grid-type control on the torsional vibration characteristics of the shaft system from the perspective of damping. It cannot point out that the phase difference between electromagnetic torque and generator speed caused by the slower dynamic characteristics of grid-type control is the root cause of the continuous oscillation or even oscillation divergence of the grid-type wind turbine shaft system.

[0065] In summary, most existing analytical methods are based on the complex torque coefficient method and do not analyze the shaft torsional vibration characteristics of grid-type wind turbines from a frequency domain perspective, using phase as the research target. Therefore, technicians cannot obtain technical inspiration from existing patent literature to propose the shaft torsional vibration suppression strategy provided by this invention.

[0066] Existing shaft torsional vibration suppression strategies for wind turbines fall into two categories. One category superimposes the compensation output of the shaft torsional vibration suppression strategy onto the DC bus voltage control stage of the converter. The other category superimposes the compensation output of the shaft torsional vibration suppression strategy onto the active power / torque control stage of the converter. Regarding the former, in the technical solution provided in patent document CN107017647A, the compensation superimposed on the DC bus voltage control stage cannot effectively suppress the shaft torsional vibration of the doubly-fed induction generator (DFIG) wind turbine due to the decoupling of the grid-side converter, and it also causes fluctuations in the DC bus voltage during shaft torsional vibration. Regarding the latter, the compensation superimposed on the active power / electromagnetic torque command value is affected by the grid-type control stage under grid-type control, causing a phase difference between the compensation and the generator speed in the shaft's inherent oscillation frequency band. When the phase difference is large, the compensation generated by the suppression strategy can actually provide torque to the generator speed, amplifying the shaft torsional vibration of the turbine.

[0067] Specifically, such as Figure 3 As shown, the inertial response capability of the grid-type unit increases, i.e., H vsgWhen the electromagnetic torque and generator speed components in the shaft system's natural oscillation frequency band are increased without a suppression strategy, the phase difference between them increases. After the existing suppression strategy is added, it cannot change the phase difference between the generator speed and electromagnetic torque components in the shaft system's natural oscillation frequency band, and it increases the amplitude of the electromagnetic torque component in this frequency band. Therefore, it will further deteriorate the shaft system's torsional vibration characteristics, leading to shaft system oscillation divergence problems.

[0068] After implementing the shaft torsional vibration suppression strategy provided by this invention, as follows: Figure 5 As shown, compared with the unsuppressed strategy, the proposed suppression strategy can effectively suppress and converge the shaft torsional vibration that should have diverged within 3.5s because it can correct the phase difference between the components of electromagnetic torque and generator speed in the natural oscillation frequency band of the shaft system. This solves the problem of shaft oscillation divergence in grid-type units.

[0069] In summary, existing shaft torsional vibration suppression strategies have limited damping capacity under grid-type control and cannot guarantee rapid suppression of shaft torsional vibration in grid-type wind turbines. The suppression strategy proposed in this paper solves the problem of shaft oscillation divergence in grid-type turbines and can effectively suppress shaft torsional vibration in grid-type wind turbines.

[0070] The present invention provides a method for suppressing torsional vibration of the shaft system of a grid-type wind turbine, comprising:

[0071] Step S1 uses a speed sensor to collect the speed of the wind turbine in real time to obtain the generator angular velocity;

[0072] Step S2: Input the generator angular velocity obtained in step S1 into the virtual phase angle damping controller. The virtual phase angle damping controller extracts the oscillation component from the generator angular velocity, calculates and generates a virtual phase angle compensation amount, and superimposes the virtual phase angle compensation amount onto the synchronous phase angle output by the grid-type control technology, i.e., θ. syn The phase angle θ of the internal potential of the converter is above. GFM ;

[0073] The virtual phase angle damping controller is used to extract the oscillation component in the generator angular velocity and calculate the virtual phase angle compensation. Any controller that can achieve this function can be called a virtual phase angle damping controller. The virtual phase angle damping controller in this embodiment consists of a bandpass filter and a PI controller, or it can be composed of an adaptive quasi-resonant controller.

[0074] The proposed method for suppressing shaft torsional vibration of grid-type wind turbines based on virtual phase angle compensation can be applied to wind turbines based on grid-type control technology, including: doubly fed wind turbines, full-power wind turbines, and permanent magnet wind turbines.

[0075] Specifically, in step S2:

[0076] The phase angle compensation amount, θ, output by the virtual phase angle damping controller comp This is superimposed on the synchronization phase angle output based on the network control technology, i.e., θ. syn "Above" refers to the superposition of the synchronous phase angle generated by the network control technology with the phase angle compensation output by the virtual phase angle damping controller, which becomes the internal potential phase angle θ of the converter. GFM Furthermore, based on the power transmission equation between the wind turbine and the power grid and the conversion relationship between active power and electromagnetic torque, the electromagnetic torque is reflected in the electromagnetic torque, so that the electromagnetic torque contains a component with the same frequency and phase as the generator speed oscillation component, thereby achieving rapid suppression of shaft torsional vibration.

[0077] Among them, network-based control technologies include, but are not limited to, network-based control with power as the control target, such as virtual synchronous machine control, power synchronization control, and droop control, and network-based control with DC bus voltage as the control target, such as inertial synchronization control and matching control.

[0078] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0079] The embodiment, taking the shaft torsional vibration problem of a doubly-fed induction generator (DFIG) controlled by a virtual synchronous machine as an example, demonstrates the following... Figure 1 This invention demonstrates the effectiveness of the shaft torsional vibration suppression method based on virtual phase angle compensation proposed in this invention.

[0080] The virtual synchronous machine control is expressed mathematically as follows:

[0081]

[0082] Among them, H vsg D is the inertial time constant of the virtual synchronizer. vsg ω is the damping coefficient of the virtual synchronous machine. syn θ is the angular frequency generated by the virtual synchronizer. syn Generate the phase angle for the virtual synchronizer; ω g P is the angular frequency of the power grid. eref This is the active power command value; G P-θ Generate the transfer function for the phase angle of the virtual synchronizer; ω b ω is the reference value for angular velocity; s is the differential operator in the complex field; P e This is the measured value of active power.

[0083] The transfer function of the virtual phase angle damping controller used in this embodiment is expressed as follows:

[0084]

[0085] Among them, GVADC Here is the transfer function of the virtual phase angle damped controller; G is the gain coefficient; ω C The characteristic frequency of the bandpass filter is ω, which is the natural oscillation frequency of the unit's drive shaft system. n Decide; K is the damping ratio of the bandpass filter. cp K ci These are the proportional and integral coefficients of the PI controller, respectively.

[0086] Specifically, G VADC The virtual phase angle damping control formula used in this embodiment includes a bandpass filter and a PI controller. In other cases outside this embodiment, since there is no unified control structure, other types also exist.

[0087] Using the transfer function G VADC The mathematical expression for the virtual phase angle compensation amount generated by the generator speed can be obtained as follows:

[0088] θ comp =G VADC ω G

[0089] Where, θ comp This represents the virtual phase angle compensation amount; the ω G This represents the generator's angular velocity.

[0090] To determine the natural oscillation frequency ω of the unit's drive shaft system n To accurately extract the generator speed oscillation component using a virtual phase angle damping controller and ensure the effectiveness of the proposed shaft torsional vibration suppression strategy, this embodiment treats the doubly-fed wind turbine drive shaft system as a two-mass block model and obtains the shaft system's natural oscillation frequency ω. n Its mathematical expression is shown below. In this embodiment, the natural oscillation frequency ω of the shaft system is taken. n The frequency is 1.64 Hz.

[0091]

[0092] Among them, H w H g These are the inertial time constants of the wind turbine and the generator, respectively; K s ω is the equivalent stiffness coefficient of the transmission shaft system. b The reference value for angular velocity is 100π rad / s.

[0093] When the inertial time constant H in the virtual synchronous machine control vsg As the inertial response of the wind turbine increases, its inertial response capability also increases, such as Figure 2 As shown, the phase difference between the generator speed and the electromagnetic torque gradually increases near 1.64Hz.vsg When the phase difference is large enough, the phase difference between the two is greater than 90°, which can lead to shaft oscillation and divergence problems.

[0094] Figure 3 This demonstrates the effectiveness of existing shaft torsional vibration suppression strategies in suppressing shaft torsional vibration under grid-type control.

[0095] Among them, the simulation model adopts such as Figure 4 The grid-connected doubly fed wind turbine model shown is simulated with an incoming wind speed of 8 m / s. A 30 MW active load is set at a distance of 0.262 pu from the wind turbine's grid connection point and 0.005 pu from the infinite grid's equivalent impedance per unit, and is connected to the grid as an external disturbance to induce torsional vibration of the shaft system.

[0096] from Figure 3 It can be seen that, with H vsg As H increases, the phase difference between the generator speed and the electromagnetic torque gradually increases. vsg When the phase difference between the two phases reaches 8°, the phase difference is already greater than 90°. At this point, the shaft system oscillates and diverges under external disturbances. After the existing shaft system torsional vibration suppression strategy is added, it not only makes... Figure 3 The problem of the shaft system shown in (b) already exhibiting oscillation and divergence has become even more severe, and as... Figure 3 As shown in (a), the shaft system, which was originally able to converge after a period of time, exhibits oscillation divergence, indicating that the existing torsional vibration suppression strategy under grid-type control not only fails to effectively suppress shaft torsional vibration, but also worsens the torsional vibration characteristics of the shaft system.

[0097] The shaft torsional vibration suppression method based on virtual phase angle compensation proposed in this invention is applied to a grid-type doubly-fed wind turbine. (See attached diagram) Figure 5 As shown, the method proposed in this invention can, during the torsional vibration of the unit shaft system induced by external disturbances, superimpose a virtual phase angle compensation amount into the electromagnetic torque, such as... Figure 5 (c) shows a component with the same frequency and phase as the generator speed oscillation component, which allows the electromagnetic torque to actively provide resistance torque during the generator speed oscillation, thus... Figure 5 As shown in (a), the shaft oscillation divergence problem of the grid-type unit caused by improper control parameter values ​​under the unsuppressed strategy was resolved in only about 3.5 seconds. This demonstrates that the method achieved the expected results and is beneficial for extending the unit's service life.

[0098] The present invention also provides a torsional vibration suppression system for the drive shaft of a grid-type wind turbine. The torsional vibration suppression system for the drive shaft of a grid-type wind turbine can be implemented by executing the process steps of the torsional vibration suppression method for the drive shaft of a grid-type wind turbine. That is, those skilled in the art can understand the torsional vibration suppression method for the drive shaft of a grid-type wind turbine as a preferred embodiment of the torsional vibration suppression system for the drive shaft of a grid-type wind turbine.

[0099] A shaft torsional vibration suppression system for a grid-type wind turbine provided by the present invention includes:

[0100] Module M1: Real-time acquisition of wind turbine rotation speed to obtain generator angular velocity;

[0101] Module M2: The generator angular velocity ω G Input a virtual phase angle damping controller; the phase angle damping controller extracts the oscillation component in the generator angular velocity of the wind turbine and calculates the virtual phase angle compensation amount;

[0102] Module M3: The virtual phase angle compensation is superimposed on the synchronous phase angle output by the grid-type control technology, thereby suppressing the torsional vibration of the wind turbine shaft system.

[0103] A computer-readable storage medium storing a computer program, characterized in that, when the computer program is executed by a processor, it implements the steps of the method for suppressing torsional vibration of the grid-type wind turbine shaft system.

[0104] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the computer program, when executed by the processor, implements the steps of the method for suppressing torsional vibration of the grid-type wind turbine shaft system.

[0105] Those skilled in the art will understand that, besides implementing the system and its various devices, modules, and units provided by this invention in the form of purely computer-readable program code, the same functions can be achieved entirely through logical programming of the method steps, making the system and its various devices, modules, and units of this invention function in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers. Therefore, the system and its various devices, modules, and units provided by this invention can be considered as a hardware component, and the devices, modules, and units included therein for implementing various functions can also be considered as structures within the hardware component; alternatively, the devices, modules, and units for implementing various functions can be considered as both software modules implementing the method and structures within the hardware component.

[0106] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A method for suppressing torsional vibration of a shaft system of a grid- connected wind turbine generator, characterized by, include: Step S1: Real-time acquisition of wind turbine rotation speed to obtain generator angular velocity; Step S2: Input the generator angular velocity into the virtual phase angle damping controller; The phase angle damping controller extracts the oscillation component in the generator angular velocity of the wind turbine and calculates the virtual phase angle compensation amount. Step S3: The virtual phase angle compensation is superimposed on the synchronous phase angle output by the grid-type control technology to suppress the torsional vibration of the wind turbine shaft system; In step S3, the synchronization phase angle is obtained through a virtual synchronizer; The control function of the virtual synchronizer is expressed mathematically as follows: in, The inertial time constant of the virtual synchronizer; The damping coefficient of the virtual synchronizing machine; The angular frequency generated for the virtual synchronizer. Generate phase angles for the virtual synchronizer; The angular frequency of the power grid; This is the active power command value; Generate a transfer function for the phase angle of the virtual synchronizer; This is the reference value for angular velocity; A differential operator over the complex field; This is the measured value of active power.

2. The method for suppressing torsional vibration of the shaft system of a grid-type wind turbine according to claim 1, characterized in that, In step S1, the wind turbine includes: a doubly fed wind turbine and a permanent magnet wind turbine. The natural oscillation frequency of the wind turbine's shaft system is mathematically expressed as follows: in, This is the natural oscillation frequency of the shaft system; , These are the inertial time constants of the wind turbine and the generator, respectively. This is the equivalent stiffness coefficient of the transmission shaft system; This is the reference value for angular velocity; In step S2, the virtual phase angle damping controller is used to extract the oscillation component in the generator angular velocity; The virtual phase angle damping controller includes: a bandpass filter and a PI controller; the PI controller is connected to the bandpass filter; The transfer function of the virtual phase angle damping controller is expressed mathematically as follows: in, Let be the transfer function of the virtual phase angle damping controller. This is the gain coefficient; The characteristic frequency of the bandpass filter is determined by the natural oscillation frequency of the unit's drive shaft system. Decide; The damping ratio of the bandpass filter; , These are the proportional coefficient and integral coefficient of the PI controller, respectively. It is a differential operator over the complex field.

3. The method for suppressing torsional vibration of the shaft system of a grid-type wind turbine according to claim 2, characterized in that, The mathematical expression for the virtual phase angle compensation is: in, Indicates the virtual phase angle compensation amount; the This represents the generator's angular velocity.

4. A shaft torsional vibration suppression system for a grid-type wind turbine generator, characterized in that, include: Module M1: Real-time acquisition of wind turbine rotation speed to obtain generator angular velocity; Module M2: Inputs the generator angular velocity into the virtual phase angle damping controller; The phase angle damping controller extracts the oscillation component in the generator angular velocity of the wind turbine and calculates the virtual phase angle compensation amount. Module M3: The virtual phase angle compensation is superimposed on the synchronous phase angle output by the grid-type control technology, thereby suppressing the torsional vibration of the wind turbine shaft system; In module M3, the synchronization phase angle is obtained through a virtual synchronizer; The control function of the virtual synchronizer is expressed mathematically as follows: in, The inertial time constant of the virtual synchronizer; The damping coefficient of the virtual synchronizing machine; The angular frequency generated for the virtual synchronizer. Generate phase angles for the virtual synchronizer; The angular frequency of the power grid; This is the active power command value; Generate a transfer function for the phase angle of the virtual synchronizer; This is the reference value for angular velocity; A differential operator over the complex field; This is the measured value of active power.

5. The torsional vibration suppression system for the shaft system of a grid-type wind turbine according to claim 4, characterized in that, In module M1, the wind turbine includes: a doubly fed wind turbine and a permanent magnet wind turbine. The natural oscillation frequency of the wind turbine's shaft system is mathematically expressed as follows: in, This is the natural oscillation frequency of the shaft system; , These are the inertial time constants of the wind turbine and the generator, respectively. This is the equivalent stiffness coefficient of the transmission shaft system; This is the reference value for angular velocity; In module M2, the virtual phase angle damping controller is used to extract the oscillation component in the generator angular velocity; The virtual phase angle damping controller includes: a bandpass filter and a PI controller; the PI controller is connected to the bandpass filter; The transfer function of the virtual phase angle damping controller is expressed mathematically as follows: in, Let be the transfer function of the virtual phase angle damping controller. This is the gain coefficient; The characteristic frequency of the bandpass filter is determined by the natural oscillation frequency of the unit's drive shaft system. Decide; The damping ratio of the bandpass filter; , These are the proportional coefficient and integral coefficient of the PI controller, respectively. It is a differential operator over the complex field.

6. The shaft torsional vibration suppression system for a grid-type wind turbine generator according to claim 5, characterized in that, The mathematical expression for the virtual phase angle compensation is: in, Indicates the virtual phase angle compensation amount; the This represents the generator's angular velocity.

7. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the method for suppressing torsional vibration of the shaft system of a grid-type wind turbine as described in any one of claims 1 to 3.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the computer program is executed by the processor, it implements the steps of the method for suppressing torsional vibration of the shaft system of a grid-type wind turbine as described in any one of claims 1 to 3.

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