Linear active-disturbance-rejection control method and device for speed regulation system of wind turbine generator

Abstract

The invention relates to the technical field of new energy power generation system control, and discloses a linear active-disturbance-rejection control method and device for a wind turbine generator speed regulation system. The method comprises the steps that the control process of the adjustable guide vane is abstracted into a second-order disturbed system, the sum of unmodeled dynamics, parameter perturbation and external disturbance in the system is defined as total disturbance, a linear expansion state observer is constructed, the system state and the total disturbance are observed and estimated in real time, and the control process of the adjustable guide vane is optimized. And a linear state error feedback control law is constructed based on the estimation result to generate a control instruction, and the instruction is used for adjusting the opening degree of the adjustable guide vane, so that the input rotating speed of the synchronous generator rapidly and stably tracks the set value. According to the invention, the stability and the anti-interference capability of the system are effectively enhanced, the control precision and the response speed are obviously improved, the structure is simple and clear, and parameter setting is convenient.

Description

Technical Field

[0001] This application relates to the field of control technology for new energy power generation systems, and in particular to a linear active disturbance rejection control method and device for a wind turbine speed regulation system. Background Technology

[0002] As the capacity of individual wind turbine units continues to increase, the capacity of the frequency converters required for the speed control systems of variable speed constant frequency wind turbine units is constantly increasing, making the control systems more complex and power losses increasingly significant. At the same time, the frequency converters inject a large amount of harmonic current into the power grid during operation, affecting power quality and leading to reduced reliability and shortened lifespan of wind turbine units, posing numerous challenges to the wind power industry.

[0003] Currently, mechanical-hydraulic front-end speed-regulating wind turbines employ brushless self-excited synchronous generators, which possess good power quality and high reliability. However, their speed regulation systems suffer from slow response speed, poor stability, and insufficient control precision, especially given the high proportion of renewable energy integrated into the grid. While existing PID control methods are simple and easy to use, their inherent limitations become apparent when facing complex environments such as strong nonlinear wind speed changes and grid disturbances, making it difficult to meet the grid's requirements for rapid and precise regulation of wind turbines.

[0004] Therefore, there is an urgent need for a new control method that can improve the response speed, control accuracy, and anti-disturbance capability of the mechanical-hydraulic front-end speed-regulating wind turbine system, so as to meet the high stability and high precision regulation requirements of modern power grids for wind turbines. Summary of the Invention

[0005] This application provides a linear active disturbance rejection control method and apparatus for a wind turbine speed regulation system, aiming to solve the technical problems of slow response, weak anti-interference capability, and insufficient control accuracy in existing mechanical-hydraulic front-end speed-regulating wind turbines due to the use of traditional PID control strategies. Through the improved method of this invention, the inherent grid-friendly architecture advantages of this type of wind turbine can be fully utilized, meeting the urgent needs of high-proportion renewable energy grids for rapid and precise power regulation.

[0006] In a first aspect, this application provides a linear active disturbance rejection control method for a wind turbine speed regulation system, applied to a mechanical-hydraulic front-end speed-regulating wind turbine. The wind turbine speed regulation system includes a hydraulic speed regulation device with adjustable guide vanes. The method takes the input speed of the synchronous generator as the control target, and the method includes: The control process of the adjustable guide vane is abstracted into a second-order disturbed system, and the sum of the unmodeled dynamics, parameter perturbations and external disturbances in the system is defined as the total disturbance. For a second-order disturbed system, a linear extended state observer is constructed to perform real-time observation and estimation of the system state and total disturbance of the second-order disturbed system. Based on the observation results of the linear extended state observer, a linear state error feedback control law containing a disturbance compensation term is constructed to generate control commands for the adjustable guide vanes. The opening of the adjustable guide vanes is adjusted according to the control command, so that the input speed of the synchronous generator can quickly and stably track the set value.

[0007] In conjunction with the first aspect, in the first implementation of the first aspect of this application, the second-order disturbed system is a disturbed system model describing the dynamic relationship between the change in the opening of the adjustable guide vane and the change in the input speed of the synchronous generator. The model expression is: , in, and These represent the change in servo motor rotation angle and the deviation in synchronous speed, respectively. x1 and x2 represent the total disturbance of the system, and x1 and x2 represent the system state variables. External disturbances For time, This indicates the system control gain.

[0008] In conjunction with the first aspect, a linearly extended state observer is constructed in the second implementation of the first aspect of this application. Specifically, the second-order disturbed system model is transformed into a state-space form, and the total disturbance is extended into new state variables for observation, thus constructing a third-order linearly extended state observer, whose state equation is: , In the above formula, e represents the observer's output estimation error. This represents the state variable matrix of a linearly extended state observer. This represents the gain matrix of the observer.

[0009] In conjunction with the first aspect, in the third implementation of the first aspect of this application, the observer gain matrix is ​​determined by configuring the observer poles, wherein the configuration method is to place all the observer poles at the same location. ,in, For the observer bandwidth, at this time .

[0010] In conjunction with the first aspect, in the fourth implementation of the first aspect of this application, the linear state error feedback control law is a proportional-derivative linear control law, and the calculation method of its output initial control quantity u0 is as follows: , Where r is the deviation between the target speed and the actual speed, and k p and k d These are proportional gain and differential gain, respectively. and The observer state variables are used to achieve system state estimation and total disturbance estimation.

[0011] In conjunction with the first aspect, in the fifth implementation of the first aspect of this application, the proportional gain k p and differential gain k d Based on controller bandwidth Adjustments are made to satisfy: , .

[0012] In conjunction with the first aspect, in the sixth implementation of the first aspect of this application, the control command for generating the adjustable guide vane is obtained by: feeding forward the initial control quantity calculated by the linear state error feedback control law and the estimated value of the total disturbance by the linear extended state observer, and dividing by the system control gain.

[0013] In conjunction with the first aspect, in the seventh implementation of the first aspect of this application, the parameter tuning of the controller in the linear active disturbance rejection control method is accomplished by adjusting the observer bandwidth, the controller bandwidth, and the control gain.

[0014] In conjunction with the first aspect, in the eighth implementation of the first aspect of this application, the external disturbances include random wind speed fluctuations and power grid fluctuations.

[0015] Secondly, this application provides a linear active disturbance rejection control device for a wind turbine speed regulation system, the device comprising: The model building module is used to abstract the control process of the adjustable guide vane into a second-order disturbed system, and to define the sum of the unmodeled dynamics, parameter perturbations and external disturbances in the system as the total disturbance. The observer construction module is used to build a linear extended state observer for a second-order disturbed system, which is used to observe and estimate the system state and total disturbance of the second-order disturbed system in real time. The feedback control module is used to construct a linear state error feedback control law containing a disturbance compensation term based on the observation results of the linear extended state observer, and generate control commands for the adjustable guide vanes. The command adjustment module is used to adjust the opening of the adjustable guide vanes according to the control command, so that the input speed of the synchronous generator can quickly and stably track the set value.

[0016] Compared with the prior art, the beneficial effects of the technical solution of this application are at least as follows: 1. Significantly enhances system stability: By actively compensating for internal and external disturbances in the system in real time, it greatly suppresses power oscillations caused by sudden changes in wind speed, hydraulic pulsation, or grid faults, thereby improving the robustness and anti-interference capability of the unit in complex operating environments.

[0017] 2. Achieve higher control precision: The estimation and compensation of total disturbance effectively eliminates steady-state error, enabling the unit's active power output or speed control to more accurately track the target command and meet the grid's stringent requirements for power control precision.

[0018] 3. Significantly improved response speed: The feedforward compensation mechanism of linear active disturbance rejection control can offset the impact of disturbances in near real time, reducing the lag in system regulation and enabling the speed control system to respond more quickly to fast control commands such as grid frequency regulation and voltage regulation, thus adapting to the power system's demand for fast-regulating resources.

[0019] 4. Simplified engineering implementation: Compared with complex nonlinear control or advanced algorithms that rely on accurate models, the linear active disturbance rejection controller has a relatively simple structure, the parameter tuning has clear physical meaning and is less numerous, making it easier to debug and apply in actual engineering. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a flowchart of a linear active disturbance rejection control method for a wind turbine speed regulation system according to this application; Figure 2 This is a schematic diagram of the basic structure of the LADRC controller in this application; Figure 3 This is a schematic diagram of the linear active disturbance rejection control scheme of the mechanical-hydraulic front-end speed-regulating wind turbine speed control system according to an embodiment of this application; Figure 4 This is a schematic diagram of the linear active disturbance rejection control device for a wind turbine speed regulation system according to this application. Detailed Implementation

[0022] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein. Furthermore, the terms “comprising” or “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0023] For ease of understanding, the specific process of the embodiments of this application is described below. The present invention provides a linear active disturbance rejection control method for a wind turbine speed regulation system, applied to a mechanical-hydraulic front-end speed-regulating wind turbine. The wind turbine speed regulation system includes a hydraulic speed regulation device with adjustable guide vanes. The method uses the input speed of the synchronous generator as the control target. Figure 1 The diagram shows a flowchart of the method of the present invention, which specifically includes the following steps: S1. The control process of the adjustable guide vane is abstracted into a second-order disturbed system, and the sum of the unmodeled dynamics, parameter perturbations and external disturbances in the system is defined as the total disturbance.

[0024] In one specific embodiment, the second-order disturbed system is a disturbed system model describing the dynamic relationship between the change in the opening of the adjustable guide vane and the change in the input speed of the synchronous generator. The model expression is: , in, and These represent the change in servo motor rotation angle and the deviation in synchronous speed, respectively. x1 and x2 represent the total disturbance of the system, and x1 and x2 represent the system state variables. External disturbances For time, This indicates the system control gain.

[0025] In a preferred embodiment, the external disturbances include random wind speed fluctuations and power grid fluctuations.

[0026] Specifically, the core transmission chain of a wind turbine is: wind turbine → speed-increasing gearbox → hydraulic speed regulator → synchronous generator. The control objective is to maintain a constant input speed of the synchronous generator. To achieve this objective, the core actuator is the adjustable guide vanes in the hydraulic speed regulator. Changes in their opening directly adjust the circulating flow rate within the hydraulic torque converter, thereby altering the torque and speed transmitted to the generator. This physical process involves complex fluid dynamics and mechanical dynamics, exhibiting significant nonlinearity and uncertainty. Therefore, a Linear Active Disturbance Rejection Control (LADRC) architecture is employed as the core controller for the mechanical-hydraulic speed regulation system.

[0027] In practical implementation, the control process of the wind turbine speed regulation system is first abstracted as a second-order disturbed system. This disturbed system model is used to describe the dynamic relationship between the change in the opening of the adjustable guide vanes and the change in the input speed of the synchronous generator. Specifically, the system state variables include x1, which is the state variable related to the change in the opening of the adjustable guide vanes, and x2, which is the state variable related to the change in the input speed of the synchronous generator.

[0028] This second-order disturbed system is affected by multiple disturbances, including unmodeled dynamics, parametric perturbations, and external disturbances. Unmodeled dynamics refer to complex nonlinear behaviors in the wind turbine, such as the dynamic effects of friction and mechanical systems, which are difficult to model accurately. Parametric perturbations are disturbances caused by changes in parameters during wind turbine operation (e.g., component aging or changes in the operating environment). External disturbances mainly come from random variations in wind speed and fluctuations in the power grid. These factors all affect the power output of the wind turbine and the speed control of the synchronous generator. To simplify the modeling process and effectively address these disturbances, this invention defines all disturbance sources as a single total disturbance, and compensates for the entire system using this total disturbance. This method allows the control system to comprehensively consider all disturbance sources, avoiding the limitations that may arise from single-source disturbance handling methods.

[0029] Based on this, a simplified control model is established: For the application of LADRC, the "guide vane opening command" is... To the generator input speed This complex mechanical-hydraulic transmission process can be abstracted into a standard second-order system model, such as... The system control gain is set to an approximate value based on initial system identification or engineering experience (e.g., let...). =10), its accuracy is not necessary, and LADRC has the ability to automatically compensate for its deviation.

[0030] Through the above modeling process, the complex system dynamics are abstracted into a second-order disturbed system, and unified compensation is performed through the total disturbance, so that the system can adapt to various disturbance sources and achieve fast and accurate control under dynamic conditions.

[0031] S2. For a second-order disturbed system, construct a linear extended state observer to perform real-time observation and estimation of the system state and total disturbance of the second-order disturbed system.

[0032] In one specific embodiment, a linearly extended state observer is constructed by: transforming the second-order disturbed system model into a state-space form, and extending the total disturbance into new state variables for observation, thereby constructing a third-order linearly extended state observer with the following state equation: , In the above formula, e represents the observer's output estimation error. This represents the state variable matrix of a linearly extended state observer. This represents the gain matrix of the observer.

[0033] In a preferred embodiment, the observer gain matrix is ​​determined by configuring the observer poles such that all the observer poles are located at the same position. ,in, For the observer bandwidth, at this time .

[0034] Specifically, to achieve precise control of the wind turbine speed control system, a Linear Extended State Observer (LESO) is constructed to observe and estimate the state variables and total disturbance of the second-order disturbed system in real time. Specifically, the second-order disturbed system model is first transformed into a state-space form, and the total disturbance is introduced into the system state-space model as an extended state variable. Through this process, a third-order linear extended state observer is constructed to achieve effective estimation of the system state and total disturbance.

[0035] The second-order disturbed system model can be transformed into state-space form, which can be expressed as the state equation expression: , From the above state equation expression, the mathematical expression for the third-order linear extended state observer can be obtained as follows: , In the above formula, e represents the observer's output estimation error. This represents the state variable matrix of a linearly extended state observer. This represents the gain matrix of the observer.

[0036] Based on the mathematical expression of the third-order linearly extended state observer (LESO), a third-order linearly extended state observer (LESO) is constructed. Its state variable matrix is ​​as follows: Real-time servo motor rotation angle change Differential of servo motor rotation angle and total disturbance .

[0037] To optimize observer performance, the observer's pole locations are determined by configuring the observer gain matrix. In a preferred embodiment, to improve estimation accuracy, all observer poles are configured to be located at the same position. This configuration ensures a fast response of the observer when estimating total disturbances and effectively avoids excessive oscillations in the system. The observer's pole configuration allows it to adapt to dynamic changes in the system and maintain efficient disturbance compensation capabilities.

[0038] Observer bandwidth The settings are based on the desired perturbation observation rate and the system noise level (e.g., =20 rad / s). The larger the value, the faster the perturbation estimation, but the more sensitive it is to measurement noise.

[0039] The three poles of the above observer are configured in the same location, let's call it... Then we can get: That is, the gain matrix Substitute =20, then .

[0040] The observer generates a system state estimate based on real-time acquired state estimates and total disturbance estimates. Using these estimates, the controller adjusts the system control input, thereby regulating the opening of the adjustable guide vanes. Ultimately, by compensating for disturbances in the system, it ensures that the synchronous generator's input speed quickly and stably tracks the setpoint.

[0041] S3. Based on the observation results of the linear extended state observer, construct a linear state error feedback control law containing a disturbance compensation term, and generate control commands for the adjustable guide vanes.

[0042] In one specific embodiment, the linear state error feedback control law is a proportional-derivative linear control law, and its initial control quantity u0 is calculated as follows: , Where r is the deviation between the target speed and the actual speed, and k p and k d These are proportional gain and differential gain, respectively. and The observer state variables are used to achieve system state estimation and total disturbance estimation.

[0043] Specifically, using the observations from the Linear Extended State Observer (LESO), a linear state error feedback control law is constructed. Combined with a disturbance compensation term, this ultimately generates a control command to adjust the adjustable guide vane opening. Specifically, the control law employed is a proportional-derivative (PD) control law. The PD linear control combination can transform abrupt input signals into relatively stable input signals, improving the system overshoot problem caused by abrupt input signals, effectively enhancing system performance and control accuracy, and reducing system fluctuations caused by disturbances.

[0044] The Linear Extended State Observer (LESO) is used to estimate the system's state variables and total disturbance in real time. In the application of this invention, LESO observes the system state and outputs estimates of the state variables x1 (adjustable guide vane opening) and x2 (synchronous generator input speed) as well as the total disturbance f. Through LESO, the system can accurately obtain real-time state information, providing necessary data support for subsequent control.

[0045] Based on the state estimates obtained from LESO, a linear state error feedback control law is constructed as the core component of the system control strategy. The main function of this control law is to provide feedback based on the system's state estimation error, thereby adjusting the control input to ensure that the synchronous generator's input speed is stable and accurately tracks the setpoint.

[0046] In a preferred embodiment, the proportional gain k p and differential gain k d Based on controller bandwidth Adjustments are made to satisfy: , .

[0047] Specifically, the controller's bandwidth determines the system's response speed and stability. Bandwidth Typically related to the system's natural frequency, bandwidth determines the controller's adjustment accuracy and responsiveness. Excessive bandwidth may lead to over-response, while insufficient bandwidth may result in sluggish response. Therefore, bandwidth... The settings need to be adjusted according to the actual working conditions and system requirements.

[0048] Once the controller bandwidth is determined proportional gain k p and differential gain k d This can be calculated using the formula above. In the formula, the proportional gain k... p It is proportional to the square of the natural frequency, while the differential gain k d It is twice the natural frequency. Through these settings, the control system can achieve the desired response speed and control accuracy. Both poles of the closed-loop system are at... .

[0049] This gain tuning method ensures that the controller can respond quickly under dynamic conditions and provide sufficient anti-interference capability in the face of disturbances. By adjusting the proportional gain and derivative gain, the speed deviation caused by external disturbances (such as wind speed fluctuations or power grid fluctuations) can be effectively reduced, while ensuring the stability of the system.

[0050] In a preferred embodiment, the control command for the adjustable guide vane is generated by: feeding forward the initial control quantity calculated by the linear state error feedback control law and the estimated value of the total disturbance by the linear extended state observer, and then dividing by the system control gain.

[0051] Specifically, the control command for the adjustable guide vane is generated by feedforward compensation of the initial control quantity calculated by the linear state error feedback control law and the estimated value of the total disturbance by the linear extended state observer, and then dividing by the system control gain to obtain the final control command.

[0052] The initial control quantity u0 is calculated using a linear state error feedback control law. In addition to feedback control, a feedforward compensation mechanism is introduced. A linear extended state observer (LESO) is used to estimate the total disturbance in the system, and the estimated value f(t) is used as the feedforward compensation term. By introducing the estimated value of the total disturbance, the influence of the disturbance can be compensated in advance in the control quantity, improving control accuracy. Feedforward compensation can effectively suppress the deviation caused by the disturbance and reduce the system's response lag to the disturbance. The compensated control quantity is: u = u0 + f(t), where f(t) is the total disturbance estimated by LESO, representing the external disturbances experienced by the system, such as wind speed fluctuations or power grid fluctuations.

[0053] To ensure system stability and response accuracy, the final control command needs to be divided by the system control gain *b*. The control gain is typically set based on the system's dynamic characteristics and can be obtained through engineering experience or system identification methods. Setting the control gain helps ensure that the system maintains a stable and accurate control response when faced with disturbances. The final control command *u* is: Where b is the system control gain, which is usually determined by the system's response requirements and performance standards.

[0054] Figure 2 This is a schematic diagram of the basic structure of the LADRC controller according to an embodiment of this application.

[0055] S4. Adjust the opening of the adjustable guide vanes according to the control command so that the input speed of the synchronous generator can quickly and stably track the set value.

[0056] Specifically, the control commands affect the output torque of the wind turbine by adjusting the opening of the adjustable guide vanes in the hydraulic speed regulator, thereby changing the input speed of the synchronous generator. More specifically, the control commands are closely related to changes in the circulating flow rate in the hydraulic torque converter; changes in flow rate directly affect torque transmission, thus achieving speed adjustment. Based on the control commands, the control system adjusts the opening of the adjustable guide vanes to ensure the input speed of the synchronous generator tracks the set value, and makes real-time adjustments based on changes in disturbances.

[0057] The input speed of the synchronous generator is acquired in real time by a measurement feedback system, and the error between the measured value and the set value is fed back to the control system. Based on the magnitude and trend of the error, the feedback system dynamically adjusts the opening of the adjustable guide vanes to ensure system stability and accuracy. When external disturbances such as wind speed or grid fluctuations occur, the control system can respond quickly, adjusting the guide vane opening to rapidly correct the speed deviation, thereby ensuring that the input speed of the synchronous generator can quickly and stably track the set value.

[0058] By precisely adjusting the opening of the adjustable guide vanes according to control commands, the system state changes rapidly, enabling the synchronous generator's input speed to be quickly adjusted when disturbances occur, avoiding response lag. Adjusting the opening of the adjustable guide vanes based on control commands effectively solves the problems of slow response, poor anti-interference capability, and insufficient control precision in existing control methods, thereby improving the overall operational stability and adjustment accuracy of the wind turbine.

[0059] In practical implementation, the adjustable guide vane control design of the mechanical-hydraulic speed regulation system is as follows: the guide vane adjustment mechanism satisfies the following relationship: ,in, The guide vane opening angle, The maximum guide vane opening angle, This refers to the gear rotation angle.

[0060] For a hydraulic torque converter, the following relationship holds: Among them, a1 to a 15 For structural parameters, Where Q is the turbine speed and Q is the circulating flow rate. arrive It is a function of the guide vane opening angle. and These represent the rate of change of flow rate and the rate of change of turbine speed, respectively.

[0061] In a preferred embodiment, in the linear active disturbance rejection control method, the controller parameters are tuned by adjusting the observer bandwidth, controller bandwidth, and control gain.

[0062] Specifically, the entire controller has only , , Three key parameters need to be tuned, with clear physical meanings (observation speed, response speed, and gain), which greatly simplifies on-site debugging.

[0063] The above process clearly demonstrates how LADRC works: Improved response speed: Due to the real-time estimation of disturbances by z3, control commands... The compensation amount is included in the calculation of u0, which eliminates the lag that traditional PID control only starts adjusting after the error occurs, and realizes near real-time feedforward control.

[0064] Enhanced stability and accuracy: z3 estimates and compensates for time-varying and nonlinear complex disturbances as a scalar, which essentially "linearizes" and "standardizes" the controlled object's dynamics, enabling high-precision and robust stable control with a simple linear PD control law, effectively suppressing power oscillations.

[0065] Simplified engineering applications: The entire controller has only , , Three key parameters need to be tuned, with clear physical meanings (observation speed, response speed, and gain), which greatly simplifies on-site debugging.

[0066] Figure 3 This is a schematic diagram of the linear active disturbance rejection control scheme for the mechanical-hydraulic front-end speed-regulating wind turbine speed control system according to an embodiment of this application. Set the rotational speed. This refers to the actual input speed of the generator. The wind turbine rotation speed, This refers to the turbine speed of the hydraulic torque converter.

[0067] The linear active disturbance rejection control method for a wind turbine speed regulation system in this application has been described above. The following describes a linear active disturbance rejection control device for a wind turbine speed regulation system in this application. Please refer to [link to relevant documentation]. Figure 4 This application provides a schematic diagram of the structure of a linear active disturbance rejection control device for a wind turbine speed regulation system. The device includes: The model building module is used to abstract the control process of the adjustable guide vane into a second-order disturbed system, and the sum of the unmodeled dynamics, parameter perturbations and external disturbances in the system is defined as the total disturbance.

[0068] The observer building module is used to construct a linear extended state observer for a second-order disturbed system, which is used to observe and estimate the system state and total disturbance of the second-order disturbed system in real time.

[0069] The feedback control module is used to construct a linear state error feedback control law containing a disturbance compensation term based on the observation results of the linear extended state observer, and generate control commands for the adjustable guide vanes.

[0070] The command adjustment module is used to adjust the opening of the adjustable guide vanes according to the control command, so that the input speed of the synchronous generator can quickly and stably track the set value.

[0071] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A linear active disturbance rejection control method for a wind turbine governing system, applied to a mechanical-hydraulic front-end governing wind turbine, the governing system of the wind turbine comprising a hydraulic governing device with adjustable guide vanes, the method taking the input speed of the synchronous generator as the control target, characterized in that, The method includes the following steps: The control process of the adjustable guide vane is abstracted as a second-order disturbed system, and the sum of the unmodeled dynamics, parameter perturbations and external disturbances in the system is defined as the total disturbance. For the second-order disturbed system, a linear extended state observer is constructed to observe and estimate the system state and the total disturbance of the second-order disturbed system in real time. Based on the observation results of the linear extended state observer, a linear state error feedback control law containing a disturbance compensation term is constructed to generate the control command for the adjustable guide vane. The opening of the adjustable guide vanes is adjusted according to the control command, so that the input speed of the synchronous generator can quickly and stably track the set value.

2. The method according to claim 1, characterized in that, The second-order disturbed system is a disturbed system model describing the dynamic relationship between the change in the opening of the adjustable guide vane and the change in the input speed of the synchronous generator. The model expression is: ， in, and These represent the change in servo motor rotation angle and the deviation in synchronous speed, respectively. x1 and x2 represent the total disturbance of the system, and x1 and x2 represent the system state variables. External disturbances For time, This indicates the system control gain.

3. The method according to claim 1, characterized in that, Constructing a linearly extended state observer involves: transforming the second-order disturbed system model into a state-space form, and extending the total disturbance into new state variables for observation, thus constructing a third-order linearly extended state observer with the following state equation: ， Where e is the output estimation error of the observer. This represents the state variable matrix of a linearly extended state observer. This represents the gain matrix of the observer.

4. The method according to claim 3, characterized in that, The observer gain matrix is ​​determined by configuring the observer poles, such that all the observer poles are located at the same position. ,in, For the observer bandwidth, at this time .

5. The method according to claim 3, characterized in that, The linear state error feedback control law is a proportional-derivative linear control law, and its initial control quantity u0 is calculated as follows: ， Where r is the deviation between the target speed and the actual speed, and k p and k d These are proportional gain and differential gain, respectively. and The observer state variables are used to achieve system state estimation and total disturbance estimation.

6. The method according to claim 5, characterized in that, The proportional gain k p and differential gain k d Based on controller bandwidth Adjustments are made to satisfy: , .

7. The method according to claim 1, characterized in that, The control command for generating the adjustable guide vane is obtained by feeding forward the initial control quantity calculated by the linear state error feedback control law and the estimated value of the total disturbance by the linear extended state observer, and then dividing by the system control gain.

8. The method according to claim 1, characterized in that, In the linear active disturbance rejection control method, the controller parameters are tuned by adjusting the observer bandwidth, controller bandwidth, and control gain.

9. The method according to claim 1, characterized in that, External disturbances include random wind speed fluctuations and power grid fluctuations.

10. A linear active disturbance rejection control device for a wind turbine speed regulation system, used to implement the method as described in any one of claims 1 to 9, characterized in that, The device includes: The model building module is used to abstract the control process of the adjustable guide vane into a second-order disturbed system, and to define the sum of the unmodeled dynamics, parameter perturbations and external disturbances in the system as the total disturbance. The observer construction module is used to construct a linear extended state observer for the second-order disturbed system, which is used to observe and estimate the system state and the total disturbance of the second-order disturbed system in real time. The feedback control module is used to construct a linear state error feedback control law containing a disturbance compensation term based on the observation results of the linear extended state observer, and generate control commands for the adjustable guide vane. The command adjustment module is used to adjust the opening of the adjustable guide vanes according to the control command, so that the input speed of the synchronous generator can quickly and stably track the set value.

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