Permanent magnet direct drive wind turbine demagnetization rotor vibration pulse damping control method

Abstract

This invention discloses a pulse-based vibration reduction control method for the demagnetized rotor of a permanent magnet direct-drive wind turbine, comprising the following steps: based on rotor dynamics theory, the unbalanced magnetic pull generated by the demagnetization of the permanent magnet direct-drive wind turbine is decomposed into terms related to the eccentricity state of the rotor system and fault disturbance terms, thus constructing the dynamic equations of the permanent magnet direct-drive wind turbine rotor system; a pulse control scheme is designed; the terms related to the eccentricity state of the rotor system are linearized using the Lipschitz condition, and the fault disturbance terms are analyzed and processed by constructing peak-to-peak gain; sufficient conditions for the pulse control scheme are derived based on Lyapunov stability theory; and the effectiveness of the designed pulse control scheme is verified through numerical simulation. This invention realizes the analysis and processing of the unbalanced magnetic pull generated by the demagnetization of a permanent magnet direct-drive wind turbine, providing a foundation for the design of a demagnetization vibration controller for permanent magnet direct-drive wind turbines.

Description

Technical Field

[0001] This invention relates to the field of wind power, and in particular to a method for vibration pulse reduction control of demagnetized rotor of permanent magnet direct-drive wind turbine. Background Technology

[0002] With the widespread application of permanent magnet synchronous motors, their unique fault type (demagnetization fault) has gradually become a key research topic for researchers.

[0003] Researchers have conducted in-depth studies on demagnetization faults in permanent magnet direct-drive wind turbines (permanent magnet synchronous motors), focusing on demagnetization cause analysis, fault diagnosis and monitoring, and motor operation performance, achieving many promising results. However, research on rotor vibration from the perspective of changes in the air gap magnetic field caused by permanent magnet demagnetization in permanent magnet synchronous motors is relatively rare. Local demagnetization of the permanent magnets in the motor rotor leads to uneven magnetic density in the internal air gap, generating unbalanced magnetic pull, causing eccentricity of the motor shaft. This eccentricity further alters the internal air gap magnetic field density, again affecting the unbalanced magnetic pull on the rotor. Therefore, the unbalanced magnetic pull caused by permanent magnet demagnetization in the permanent magnet synchronous motor rotor is a significant factor contributing to rotor demagnetization vibration.

[0004] In existing research on vibration analysis of unbalanced magnetic pull, researchers have focused on the vibration modeling problem caused by unbalanced magnetic pull. Few researchers have considered the unbalanced magnetic pull caused by demagnetization from the perspective of demagnetization of permanent magnets in permanent magnet synchronous motor rotors, and studied the vibration control problem of demagnetized rotors.

[0005] As a key component of wind power generation systems, the demagnetization failure of permanent magnet direct-drive wind turbines not only affects their own operation, but the accompanying vibrations also have a significant impact on the normal operation of the system and the service life of various components. Therefore, researching demagnetization vibration control is particularly important for demagnetization failures of the permanent magnets in the rotor of permanent magnet direct-drive wind turbines. However, due to the highly nonlinear characteristics of the unbalanced magnetic pull caused by demagnetization, it is difficult to accurately decompose and analyze it, making control difficult; furthermore, the strong nonlinear disturbances under demagnetization in permanent magnet direct-drive wind turbines make it difficult to find suitable control schemes for effective control. Consequently, few researchers have completed research on the demagnetization vibration control of permanent magnets in the rotor of permanent magnet direct-drive wind turbines. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a simple algorithm for vibration pulse reduction control of demagnetized rotor in permanent magnet direct-drive wind turbines.

[0007] The technical solution of this invention to solve the above-mentioned technical problems is: a vibration pulse reduction control method for demagnetized rotor of permanent magnet direct-drive wind turbine, comprising the following steps:

[0008] Step 1: Based on rotor dynamics theory, considering the unbalanced magnetic pull caused by the demagnetization of permanent magnet direct-drive wind turbine, the unbalanced magnetic pull generated by the demagnetization of permanent magnet direct-drive wind turbine is decomposed into terms related to the eccentricity state of the rotor system and fault disturbance terms, and the dynamic equation of the rotor system of permanent magnet direct-drive wind turbine is constructed.

[0009] Step 2: Based on the constructed dynamic equations of the permanent magnet direct-drive wind turbine rotor system, design a pulse control scheme;

[0010] Step 3: Linearize the terms related to the eccentricity of the rotor system using the Lipschitz condition, and analyze and process the fault disturbance terms by constructing the peak-peak gain condition.

[0011] Step 4: Based on Lyapunov stability theory, derive the sufficient conditions for the existence of pulse control scheme parameters that enable the permanent magnet direct-drive wind turbine rotor system to operate normally;

[0012] Step 5: Verify the effectiveness of the designed pulse control scheme through numerical simulation.

[0013] In the above-mentioned vibration pulse reduction control method for demagnetized rotor of permanent magnet direct-drive wind turbine, the dynamic equation of the permanent magnet direct-drive wind turbine rotor system constructed in step one is as follows:

[0014] (1)

[0015] in, for The vibration displacement state of the rotor system at any given time. , Indicates time, The dimension representing the direction of vibration of the rotor system. Represents the real number field; for The first derivative of represents the vibration velocity state of the rotor system; for The second derivative represents the vibration acceleration state of the rotor system; for The rotor system control input is constantly being monitored. , , These are the mass matrix coefficients, damping matrix coefficients, and stiffness matrix coefficients of the rotor system, respectively. , , ; Let be the vector of the external excitation force acting on the rotor system, and satisfy:

[0016] (2)

[0017] in, For external excitation related to the eccentric state of the rotor system, for Constant fault disturbance;

[0018] set up , express If the rotor system vibration velocity state at a given moment is true, then:

[0019] (3)

[0020] in, express The first derivative;

[0021] Rotor system control output for:

[0022] (4)

[0023] in, This is the vibration displacement output matrix for the rotor system; This is the output matrix for the vibration velocity of the rotor system.

[0024] In the aforementioned vibration pulse reduction control method for demagnetized rotors of permanent magnet direct-drive wind turbines, step one considers that in actual operation and control, the rotor system control process is based on sampled discrete data. Therefore, the sampling period is used as the basis for control. Discretize the rotor system;

[0025] set up , For discrete sampling times, the initial sampling time is... , Indicates the first Each sampling time, Therefore, there is a sampling period. satisfy ;

[0026] make equal Then, equation (3) can be discretized as follows:

[0027] (5)

[0028] in, express The vibration velocity state of the rotor system at any given moment; for The vibration displacement state of the rotor system at any given moment; for External excitations that are constantly related to the eccentricity state of the rotor system for Constant fault disturbance; for The rotor system control input is constantly being monitored.

[0029] To facilitate subsequent analysis and reasoning, the following parameters are introduced: State variable matrix at time step , The external excitation function matrix related to the eccentric state at time t. , Fault disturbance function matrix at time step , System control input variable matrix at time 1 ;

[0030] satisfy: , , , superscript Represents the transpose of a matrix; It is an all-zero matrix;

[0031] Equation (5) can then be rewritten in matrix form as follows:

[0032] (6)

[0033] in, All are transition parameter matrices of the rotor system dynamics model, satisfying ; ; ; It is the identity matrix; express The inverse matrix;

[0034] Equation (4) can be rewritten in matrix form as follows:

[0035] (7)

[0036] in, for The control output of the rotor system at any given moment; The transition parameter matrix of the rotor system control output model satisfies: .

[0037] In the above-mentioned vibration pulse reduction control method for demagnetized rotor of permanent magnet direct-drive wind turbine, step two is set when... The time is the pulse control moment, and the pulse control parameters are applied to the rotor system; when The pulse control parameters do not act on the rotor system. For pulse control period parameters, It is an integer greater than or equal to 1;

[0038] Define the pulse control time as ,but The following pulse control scheme is constructed:

[0039] (8)

[0040] in, Indicates the pulse control gain parameter; Represents the impulse function;

[0041] Combining equations (6) and (8), we have:

[0042] (9)

[0043] in, This represents the difference between the states of the two systems at the moment after the pulse controller is activated and at the moment before the pulse controller is activated.

[0044] In the above-mentioned method for vibration pulse reduction control of demagnetized rotor of permanent magnet direct-drive wind turbine, step two involves setting... , Indicates time The transient state after the pulse control action; Indicates time The transient time before the pulse control action; The transient state of the system after the pulse controller is applied satisfies: , Indicates time The transient state after the pulse control action; The transient state of the system before the pulse controller is applied satisfies: , Indicates time The transient state after the pulse control action;

[0045] Equation (9) can then be rewritten in matrix form:

[0046] (10)

[0047] In the above-mentioned vibration pulse reduction control method for demagnetized rotor of permanent magnet direct-drive wind turbine, the process of linearizing terms related to the eccentricity state of the rotor system through the Lipschitz condition in step three is as follows:

[0048] against It meets the following conditions:

[0049] (11)

[0050] in, These are the linearization parameters; for Transpose of; for The transpose of .

[0051] In the above-mentioned vibration pulse reduction control method for demagnetized rotor of permanent magnet direct-drive wind turbine, step three involves the process of analyzing and processing fault disturbance terms by constructing peak-to-peak gain conditions:

[0052] To quantify the performance of the rotor system, considering the gain ,satisfy: , Represents the fault disturbance function matrix. This indicates the control output of the rotor system. Indicates the control output of the rotor system Measurement Indicates supremum;

[0053] Peak-to-peak gain is , ; for of Norm; for of Norm.

[0054] In the above-mentioned vibration pulse reduction control method for demagnetized rotor of permanent magnet direct-drive wind turbine, in step four, if equations (12)-(14) are satisfied under given parameter conditions, then equation (10) will reach asymptotic stability under the action of the pulse controller, which is a sufficient condition for the pulse control scheme.

[0055] For all , Let be a constant, such that:

[0056] (12)

[0057] in, Let Lyapunov be the Lyapunov parameters to be solved, and let Lyapunov be a positive definite symmetric matrix. These are pulse control parameters, and their values ​​are normal numbers. These are performance measurement parameters; Represents the coefficients of performance measurement parameters. ; , All represent intermediate variable matrices, satisfying: , ; Represents the symmetric terms of a symmetric matrix; Represents the transpose of a matrix;

[0058] For each pulse control moment, the following holds:

[0059] (13)

[0060] in, This represents the specific value of the Lyapunov functional at the pulse control moment; represents the state proportionality constant at different pulse control moments. ; The vibration state of the rotor system at the moment of pulse control; for Transpose of; For the intermediate variable matrix, ; for Transpose of;

[0061] For all ,have:

[0062] (14)

[0063] in, Let be the exponential stability constant of the rotor system. ; The control interval is for maximum pulse control.

[0064] The beneficial effects of this invention are as follows:

[0065] 1. This invention addresses the demagnetization fault of permanent magnet direct-drive wind turbines and studies its demagnetization vibration control. First, based on rotor dynamics theory, considering the unbalanced magnetic pull caused by demagnetization, a dynamic equation for the permanent magnet direct-drive wind turbine rotor system is constructed. Then, a pulse control scheme is designed. Next, the Lipschitz condition is used to linearize terms related to the rotor system's eccentricity, and peak-to-peak gain is used to analyze and process fault disturbance terms. Then, based on Lyapunov stability theory, sufficient conditions for the pulse control scheme are derived. Finally, numerical simulations verify the effectiveness of the designed pulse control scheme.

[0066] 2. This invention decomposes the unbalanced magnetic pull generated by the demagnetization of a permanent magnet direct-drive wind turbine into two parts: a term related to the eccentricity of the rotor system and a fault disturbance term. The Lipschitz condition is used to linearize the term related to the eccentricity of the rotor system, and the PP gain is constructed to analyze and process the fault disturbance term. This enables the analysis and processing of the unbalanced magnetic pull generated by the demagnetization of the permanent magnet direct-drive wind turbine, providing a foundation for the design of a demagnetization vibration controller for permanent magnet direct-drive wind turbines. Attached Figure Description

[0067] Figure 1 This is the overall flowchart of the present invention.

[0068] Figure 2 This is a graph showing the change in vibration velocity of the rotor system.

[0069] Figure 3 This is a graph showing the vibration displacement variation of the rotor system.

[0070] Figure 4 This is a graph showing the change in vibration velocity of the rotor system without a controller.

[0071] Figure 5 This is a graph showing the vibration displacement variation of the rotor system without a controller. Detailed Implementation

[0072] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0073] like Figure 1 As shown, a vibration pulse reduction control method for demagnetized rotor of a permanent magnet direct-drive wind turbine includes the following steps:

[0074] Step 1: Based on rotor dynamics theory, considering the unbalanced magnetic pull caused by the demagnetization of permanent magnet direct-drive wind turbine, the unbalanced magnetic pull generated by the demagnetization of permanent magnet direct-drive wind turbine is decomposed into terms related to the eccentricity state of the rotor system and fault disturbance terms, and the dynamic equation of the rotor system of permanent magnet direct-drive wind turbine is constructed.

[0075] The dynamic equations of the permanent magnet direct-drive wind turbine rotor system are as follows:

[0076] (1)

[0077] in, for The vibration displacement state of the rotor system at any given time. , Indicates time, The dimension representing the direction of vibration of the rotor system. Represents the real number field; for The first derivative of represents the vibration velocity state of the rotor system; for The second derivative represents the vibration acceleration state of the rotor system; for The rotor system control input is constantly being monitored. , , These are the mass matrix coefficients, damping matrix coefficients, and stiffness matrix coefficients of the rotor system, respectively. , , ; Let be the vector of the external excitation force acting on the rotor system, and satisfy:

[0078] (2)

[0079] in, For external excitation related to the eccentric state of the rotor system, for Constant fault disturbance;

[0080] set up , express If the rotor system vibration velocity state at a given moment is true, then:

[0081] (3)

[0082] in, express The first derivative;

[0083] Rotor system control output for:

[0084] (4)

[0085] in, This is the vibration displacement output matrix for the rotor system; This is the output matrix for the vibration velocity of the rotor system.

[0086] Considering that in actual operation and control, the control process of the rotor system is based on sampled discretized data, therefore, the sampling period is used as the basis for control. Discretize the rotor system;

[0087] set up , For discrete sampling times, the initial sampling time is... , Indicates the first Each sampling time, Therefore, there is a sampling period. satisfy ;

[0088] make equal Then, equation (3) can be discretized as follows:

[0089] (5)

[0090] in, express The vibration velocity state of the rotor system at any given moment; for The vibration displacement state of the rotor system at any given moment; for External excitations that are constantly related to the eccentricity state of the rotor system for Constant fault disturbance; for The rotor system control input is constantly being monitored.

[0091] To facilitate subsequent analysis and reasoning, the following parameters are introduced: State variable matrix at time step , The external excitation function matrix related to the eccentric state at time t. , Fault disturbance function matrix at time step , System control input variable matrix at time 1 ;

[0092] satisfy: , , , superscript Represents the transpose of a matrix; It is an all-zero matrix;

[0093] Equation (5) can then be rewritten in matrix form as follows:

[0094] (6)

[0095] in, All are transition parameter matrices of the rotor system dynamics model, satisfying ; ; ; It is the identity matrix; express The inverse matrix;

[0096] Equation (4) can be rewritten in matrix form as follows:

[0097] (7)

[0098] in, for The control output of the rotor system at any given moment; The transition parameter matrix of the rotor system control output model satisfies: .

[0099] Step 2: Based on the constructed dynamic equations of the permanent magnet direct-drive wind turbine rotor system, design a pulse control scheme.

[0100] When set The time is the pulse control moment, and the pulse control parameters are applied to the rotor system; when The pulse control parameters do not act on the rotor system. For pulse control period parameters, It is an integer greater than or equal to 1;

[0101] Define the pulse control time as ,but The following pulse control scheme is constructed:

[0102] (8)

[0103] in, Indicates the pulse control gain parameter; Represents the impulse function;

[0104] Combining equations (6) and (8), we have:

[0105] (9)

[0106] in, This represents the difference between the states of the two systems at the moment after the pulse controller is activated and at the moment before the pulse controller is activated.

[0107] set up , Indicates time The transient state after the pulse control action; Indicates time The transient time before the pulse control action; The transient state of the system after the pulse controller is applied satisfies: , Indicates time The transient state after the pulse control action; The transient state of the system before the pulse controller is applied satisfies: , Indicates time The transient state after the pulse control action;

[0108] Equation (9) can then be rewritten in matrix form:

[0109] (10).

[0110] Step 3: Linearize the terms related to the eccentricity of the rotor system using the Lipschitz condition, and analyze and process the fault disturbance terms by constructing the peak-peak gain condition.

[0111] The process of linearizing terms related to the eccentricity state of the rotor system using the Lipschitz condition is as follows:

[0112] against It meets the following conditions:

[0113] (11)

[0114] in, These are the linearization parameters; for Transpose of; for The transpose of .

[0115] The process of analyzing and processing fault disturbance terms by constructing peak-peak gain conditions is as follows:

[0116] To quantify the performance of the rotor system, considering the gain ,satisfy: , Represents the fault disturbance function matrix. This indicates the control output of the rotor system. Indicates the control output of the rotor system Measurement Indicates supremum;

[0117] Peak-to-peak gain is , ; For signal of Norm; for of Norm.

[0118] This invention decomposes the unbalanced magnetic pull generated by the demagnetization of a permanent magnet direct-drive wind turbine into two parts: a term related to the eccentricity of the rotor system and a fault disturbance term. The Lipschitz condition is used to linearize the term related to the eccentricity of the rotor system, and the peak-to-peak gain (PP gain) is constructed to analyze and process the fault disturbance term. This enables the analysis and processing of the unbalanced magnetic pull generated by the demagnetization of the permanent magnet direct-drive wind turbine, providing a foundation for the design of a demagnetization vibration controller for permanent magnet direct-drive wind turbines.

[0119] Step 4: Based on Lyapunov stability theory, derive the sufficient conditions for the existence of pulse control scheme parameters that enable the permanent magnet direct-drive wind turbine rotor system to operate normally.

[0120] Under given parameter conditions, if equations (12)-(14) are satisfied, then equation (10) will reach asymptotic stability under the action of the pulse controller, which is a sufficient condition for the pulse control scheme;

[0121] For all , Let be a constant, such that:

[0122] (12)

[0123] in, Let Lyapunov be the Lyapunov parameters to be solved, and let Lyapunov be a positive definite symmetric matrix. These are pulse control parameters, and their values ​​are normal numbers. These are performance measurement parameters; Represents the coefficients of performance measurement parameters. ; , All represent intermediate variable matrices, satisfying: , ; Represents the symmetric terms of a symmetric matrix; To represent the transpose of a matrix, in subsequent equations... The meanings are the same;

[0124] For each pulse control moment, the following holds:

[0125] (13)

[0126] in, This represents the specific value of the Lyapunov functional at the pulse control moment; represents the state proportionality constant at different pulse control moments. ; The vibration state of the rotor system at the moment of pulse control; for Transpose of; For the intermediate variable matrix, ; for Transpose of;

[0127] For all ,have:

[0128] (14)

[0129] in, Let be the exponential stability constant of the rotor system. ; The control interval is for maximum pulse control.

[0130] The proof of the sufficient conditions for the pulse control scheme is as follows:

[0131] Build Lyapunov Functional Time :

[0132] (15)

[0133] Next, based on Lyapunov stability theory, we will solve for the sufficient condition for stable control in equation (10). Considering that there are instantaneous state transitions in impulse control, the solution process will be divided into the condition when... Time and time When the time comes, the solution of equation (15) is completed.

[0134] when ,Right now hour, Lyapunov difference function at time t satisfy:

[0135]

[0136] , Then it exists:

[0137]

[0138] Combining equation (11), we can obtain:

[0139]

[0140] Considering the existence of fault disturbances in the rotor system, performance measurement parameters are introduced. , It is a bounded positive number. It satisfies: That is, it exists:

[0141] (16)

[0142] in, Represents the coefficients of performance measurement parameters. .

[0143] According to the definitions of equations (16) and (7), we can obtain:

[0144] ; ;

[0145] Therefore, when equation (12) exists, that is, when:

[0146]

[0147] satisfy: ;

[0148] Based on this, when Then it exists:

[0149] (17)

[0150] in, Indicates time The transient state after the pulse control action; This indicates that the Lyapunov functional at the transient moment... The specific value.

[0151] when ,Right now At that time, the following conditions are met:

[0152]

[0153] in, This indicates that the Lyapunov functional at the transient moment... The specific value; This indicates the state of the rotor system at a transient moment. The specific numerical matrix; Indicates the state of the rotor system at a transient moment. The specific numerical matrix; for transpose, for Transpose of;

[0154] Therefore, when equation (13) exists, it satisfies:

[0155] (18)

[0156] in, Indicates time The transient time before the pulse control action; This indicates that the Lyapunov functional at the transient moment... The specific value.

[0157] Combining equation (17) and equation (18), we get:

[0158] (19)

[0159] in, Indicates the index of the sampling time. This represents the specific value of the Lyapunov functional at the initial time.

[0160] According to equation (19), for all If it exists When the following conditions are met:

[0161]

[0162] Then it satisfies:

[0163] (20)

[0164] That is, when equation (14) exists, it is easy to obtain The exponent decreases and remains stable. Therefore, this is proven.

[0165] Step 5: Verify the effectiveness of the designed pulse control scheme through numerical simulation.

[0166] This invention uses the parameters of a permanent magnet synchronous motor with a rated power of 2.2KW and a rated speed of 1500r / min for simulation. Based on the characteristics of the rotor system, for the constructed initial model, i.e., equation (1), the following parameters are set: The rotor system exists in the vertical direction ( Vibration state and left-right direction ( Vibration state. The rotor mass is set to 10 kg. In both directions, , , This represents a diagonal matrix.

[0167] Based on equation (6) and combined with the actual permanent magnet synchronous motor parameters mentioned above, the parameters in the system model can be directly determined. , , Based on the sampling period The specific data will be further determined.

[0168] Based on assumption (11), set ;set up , Set the sampling period Based on the existing parameters, the following can be calculated according to equation (12): The conditions are met, and thus we can set... At the same time, it can be calculated that and ;

[0169]

[0170] In the numerical simulation process, set ,but According to formula (20), it can be set The conditions are met. Furthermore, according to equation (14), we can obtain... The conditions are met. During the numerical simulation, the following settings are made: Based on the existing solved parameters and the current state of the rotor system, the result can be obtained from equation (13). .

[0171] Set the initial data as Define the estimation function for the nonlinear function: , By combining the pulse controller with the system model, the following can be obtained: Figure 2 The rotor system vibration velocity variation curve shown is as follows: Figure 3 The diagram shows the vibration displacement variation curves of the rotor system. The black curve represents the vibration state in the vertical dimension within the rotor's vibration axis, while the blue curve represents the vibration state in the horizontal dimension. Through observation... Figure 2 and Figure 3 It can be observed that under the action of the controller, the vibration displacement state and velocity state of the rotor system are well suppressed.

[0172] To further observe the control effect of the controller, this invention provides the following... Figure 4 The diagram shows the vibration velocity variation curve of the rotor system without a controller and as shown below. Figure 5 The diagram shows the vibration displacement variation curves of the rotor system without a controller. The black curve represents the vertical vibration state within the rotor's vibration axis, while the blue curve represents the horizontal vibration state. This is achieved through observation... Figure 4 and Figure 5 It can be observed that without the action of a controller, the vibration displacement state and velocity state of the rotor system are in a divergent state.

[0173] The comparison shows that the vibration state of the rotor system is significantly suppressed under the action of the controller, which proves the effectiveness of the control method of the present invention.

Claims

1. A vibration pulse reduction control method for demagnetized rotor of a permanent magnet direct-drive wind turbine, characterized in that, Includes the following steps: Step 1: Based on rotor dynamics theory, considering the unbalanced magnetic pull caused by the demagnetization of permanent magnet direct-drive wind turbine, the unbalanced magnetic pull generated by the demagnetization of permanent magnet direct-drive wind turbine is decomposed into terms related to the eccentricity state of the rotor system and fault disturbance terms, and the dynamic equation of the rotor system of permanent magnet direct-drive wind turbine is constructed. The dynamic equations of the permanent magnet direct-drive wind turbine rotor system are discretized and transformed into matrix form: （6）； in, express The state variable matrix at time t; express The state variable matrix at time t; All are transition parameter matrices of the rotor system dynamics model; Indicates the sampling period; express The inverse matrix; express The external excitation function matrix related to the eccentric state at time t; express The fault disturbance function matrix at time t; express The system control input variable matrix at each time step; Step 2: Based on the constructed dynamic equations of the permanent magnet direct-drive wind turbine rotor system, design a pulse control scheme; When set This is the pulse control moment. Indicates time, Indicates the first At each sampling moment, the pulse control parameters act on the rotor system; when The pulse control parameters do not act on the rotor system. For pulse control period parameters, It is an integer greater than or equal to 1; Define the pulse control time as ,but The following pulse control scheme is constructed: （8）； in, Indicates the pulse control gain parameter; Represents the impulse function; express The state variable matrix at time t; express time; Then it exists: （9） ； in, This represents the difference between the states of the two systems at the moment after the pulse controller is activated and at the moment before the pulse controller is activated; Step 3: Linearize the terms related to the eccentricity of the rotor system using the Lipschitz condition, and analyze and process the fault disturbance terms by constructing the peak-peak gain condition. Step 4: Based on Lyapunov stability theory, derive the sufficient conditions for the existence of pulse control scheme parameters that enable the permanent magnet direct-drive wind turbine rotor system to operate normally; Step 5: Verify the effectiveness of the designed pulse control scheme through numerical simulation.

2. The vibration pulse reduction control method for demagnetized rotor of permanent magnet direct-drive wind turbine according to claim 1, characterized in that, In step one, the dynamic equations of the permanent magnet direct-drive wind turbine rotor system are as follows: （1）； in, for The vibration displacement state of the rotor system at any given time. , Indicates time, The dimension representing the direction of vibration of the rotor system. Represents the real number field; for The first derivative of represents the vibration velocity state of the rotor system; for The second derivative represents the vibration acceleration state of the rotor system; for The rotor system control input is constantly being monitored. , , These are the mass matrix coefficients, damping matrix coefficients, and stiffness matrix coefficients of the rotor system, respectively. , , ; Let be the vector of the external excitation force acting on the rotor system, and satisfy: （2）； in, For external excitation related to the eccentric state of the rotor system, for Constant fault disturbance; set up , express If the rotor system vibration velocity state at a given moment is true, then: （3）； in, express The first derivative; Rotor system control output for: （4）； in, This is the vibration displacement output matrix for the rotor system; This is the output matrix for the vibration velocity of the rotor system.

3. The vibration pulse reduction control method for demagnetized rotor of permanent magnet direct-drive wind turbine according to claim 2, characterized in that, In step one, considering that in actual operation and control, the rotor system control process is based on sampled discrete data, therefore, the sampling period is used... Discretize the rotor system; set up , For discrete sampling times, the initial sampling time is... , Indicates the first Each sampling time, Therefore, a sampling period exists. satisfy ; make equal Then, equation (3) can be discretized as follows: （5）； in, express The vibration velocity state of the rotor system at any given moment; for The vibration displacement state of the rotor system at any given moment; for External excitations that are constantly related to the eccentricity state of the rotor system for Constant fault disturbance; for The rotor system control input is constantly being monitored. To facilitate subsequent analysis and reasoning, the following parameters are introduced: State variable matrix at time step , The external excitation function matrix related to the eccentric state at time t. , Fault disturbance function matrix at time step , System control input variable matrix at time 1 ; satisfy: , , , superscript Represents the transpose of a matrix; It is an all-zero matrix; Equation (5) can then be rewritten in matrix form as follows: （6）； in, All are transition parameter matrices of the rotor system dynamics model, satisfying ; ; ; It is the identity matrix; express The inverse matrix; Equation (4) can be rewritten in matrix form as follows: （7）； in, for The control output of the rotor system at any given moment; The transition parameter matrix of the rotor system control output model satisfies: .

4. The vibration pulse reduction control method for demagnetized rotor of permanent magnet direct-drive wind turbine according to claim 3, characterized in that, In step two, set , Indicates time The transient state after the pulse control action; Indicates time The transient time before the pulse control action; The transient state of the system after the pulse controller is applied satisfies: , Indicates time The transient state after the pulse control action; The transient state of the system before the pulse controller is applied satisfies: , Indicates time The transient state after the pulse control action; Equation (9) can then be rewritten in matrix form: （10）。 5. The vibration pulse reduction control method for demagnetized rotor of permanent magnet direct-drive wind turbine according to claim 4, characterized in that, In step three, the process of linearizing the terms related to the eccentricity state of the rotor system using the Lipschitz condition is as follows: against It meets the following conditions: （11）； in, These are the linearization parameters; for transpose; for The transpose of .

6. The vibration pulse reduction control method for demagnetized rotor of permanent magnet direct-drive wind turbine according to claim 5, characterized in that, In step three, the process of analyzing and processing the fault disturbance term by constructing peak-peak gain conditions is as follows: To quantify the performance of the rotor system, considering the gain ,satisfy: , Represents the fault disturbance function matrix. This indicates the control output of the rotor system. Indicates the control output of the rotor system Measurement Indicates supremum; Peak-to-peak gain is , ; for of Norm; for of Norm.

7. The vibration pulse reduction control method for demagnetized rotor of permanent magnet direct-drive wind turbine according to claim 6, characterized in that, In step four, under given parameter conditions, if equations (12)-(14) are satisfied, then equation (10) will reach asymptotic stability under the action of the pulse controller, which is a sufficient condition for the pulse control scheme. For all , Let be a constant, such that: （12）； in, Let Lyapunov be the Lyapunov parameters to be solved, and let Lyapunov be a positive definite symmetric matrix. These are pulse control parameters, and their values ​​are normal numbers. These are performance measurement parameters; Represents the coefficients of performance measurement parameters. ; , All represent intermediate variable matrices, satisfying: , ; Represents the symmetric terms of a symmetric matrix; Represents the transpose of a matrix; For each pulse control moment, the following holds: （13）； in, This represents the specific value of the Lyapunov functional at the pulse control moment; represents the state proportionality constant at different pulse control moments. ; The vibration state of the rotor system at the moment of pulse control; for transpose; For the intermediate variable matrix, ; for transpose; For all ,have: （14）； in, Let be the exponential stability constant of the rotor system. ; The control interval is for maximum pulse control.

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