Control method and device of subsynchronous oscillation suppression device

Abstract

The invention relates to the technical field of oscillation suppression, in particular to a control method and device for a subsynchronous oscillation suppression device, and the method comprises the following steps: collecting the frequency of a power grid, load fluctuation, the rotating speed of a generator and the excitation state of the generator, and recognizing subsynchronous oscillation frequency signals in a power system based on real-time operation state data; the subsynchronous oscillation frequency signal comprises oscillation frequency, oscillation amplitude and oscillation phase; analyzing the time-varying characteristics of the subsynchronous oscillation frequency signal through a time-varying analysis algorithm, wherein the time-varying characteristics comprise the time-varying characteristics of the oscillation frequency, the time-varying characteristics of the oscillation amplitude and the time-varying characteristics of the oscillation phase; the frequency suppression parameters are corrected according to the time-varying characteristics, and through an adaptive controller in the subsynchronous oscillation suppression device, based on the corrected frequency suppression parameters, real-time adjustment is carried out, a control effect is applied in real time, and subsynchronous oscillation is suppressed. According to the invention, the limitation of the traditional fixed frequency hypothesis is avoided, and the risk of misjudgment and insufficient suppression is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of oscillation suppression, and in particular to a control method and device for a subsynchronous oscillation suppression device. Background Art

[0002] Sub-synchronous oscillation (SSO) is a typical low-frequency oscillation phenomenon in power systems. It usually occurs in a frequency range lower than the base frequency of the power grid (such as 50 Hz or 60 Hz). This oscillation may be caused by a variety of factors, such as the dynamic characteristics of power electronic equipment, the interaction between the generator and the power grid, and system load fluctuations. The occurrence of sub-synchronous oscillation will not only cause power quality problems, but also pose a serious threat to the stability of the power system and power generation equipment (such as generator rotors), and even cause equipment damage and system instability.

[0003] Current subsynchronous oscillation suppression methods are mostly focused on control strategies based on the fixed frequency assumption. These methods usually assume that the frequency of subsynchronous oscillations is stable or changes little in a short period of time. However, in actual operation, the frequency, amplitude and phase of subsynchronous oscillations have significant time-varying characteristics. For example, under conditions such as dynamic loads, wind power access, generator scheduling or system topology changes, the oscillation frequency may drift and the oscillation amplitude may fluctuate significantly over time. Traditional methods are difficult to adapt to this complex dynamic environment. Summary of the invention

[0004] The invention provides a control method and a device for a subsynchronous oscillation suppression device.

[0005] The control method of the subsynchronous oscillation suppression device comprises the following steps: S1: Real-time monitoring of the operating status data of the power system, collecting grid frequency, load fluctuation, generator speed, and generator excitation status, and identifying subsynchronous oscillation frequency signals in the power system based on real-time operating status data. The subsynchronous oscillation frequency signals include oscillation frequency, oscillation amplitude, and oscillation phase; S2: Analyze the time-varying characteristics of the subsynchronous oscillation frequency signal through a time-varying analysis algorithm. The time-varying characteristics include the time-varying property of the oscillation frequency, the time-varying property of the oscillation amplitude, and the time-varying property of the oscillation phase; S3: According to the time-varying characteristics, the dynamic frequency compensation control algorithm is applied to correct the frequency suppression parameters. Through the adaptive controller in the subsynchronous oscillation suppression device, real-time adjustments are made based on the corrected frequency suppression parameters, and control is applied in real time to suppress subsynchronous oscillations and avoid misjudgment of the oscillation frequency or failure to suppress it in time.

[0006] Optionally, in S1, a sensor network installed at each node of the power system is used to collect data on real-time grid frequency, load fluctuation, generator speed and generator excitation state, and the sensor network includes: Voltage sensors are used to measure grid frequency , current sensors are used to measure load fluctuations The generator has a built-in speed sensor and excitation current sensor to measure the generator speed. , Generator excitation state ; Grid frequency calculation: using voltage signals collected by voltage sensors , calculate the frequency: ,in, is the period of the voltage signal. The zero point (positive and negative alternating point) is used to determine the period ,Right now: ,in, is the voltage signal at The time point of the zero crossing, is the grid frequency; Calculation of load fluctuations: Collect load current signals through current sensors , calculate the load fluctuation: ,in, is the instantaneous active power fluctuation of the load, is the instantaneous value of voltage, is the instantaneous value of current, is the phase angle between voltage and current, Calculated by the phase detection algorithm: , is the average active power of the load, and are the effective values ​​of voltage and current respectively; Calculation of generator speed: Calculate the speed using the speed pulse signal measured by the generator speed sensor: ,in, is the generator speed, is the pulse frequency output by the sensor, is the number of pole pairs of the generator; Calculation of excitation state: Collect excitation current signal through excitation current sensor , calculate its mean and fluctuation range: ; ; in, is the average value of the excitation current, is the fluctuation amplitude of the excitation current, is the length of the measurement time window.

[0007] Optionally, the oscillation frequency is obtained based on the analysis of the operating status data, and the collected grid frequency is analyzed using Fourier transform. and generator speed Perform frequency analysis on the signal to obtain the spectrum: ,in, is the spectrum of the signal, indicating the frequency The amplitude, is the input signal, e.g. or ,express The grid frequency and generator speed at the moment, is the frequency component, and the oscillation frequency below the grid fundamental frequency is identified through the spectrum diagram , that is, the conditions are met: .

[0008] Optionally, the oscillation amplitude is extracted from a spectrum plot, expressed as: ,in, This is the subsynchronization frequency The complex spectrum value at and are the real and imaginary parts of the spectrum value, It is the oscillation amplitude of the signal at the subsynchronous frequency, indicating the strength of the oscillation.

[0009] Optionally, the oscillation phase describes the time position of the subsynchronous oscillation frequency signal, expressed as: ,in, is the oscillation frequency The corresponding oscillation phase, phase It indicates the relative time position of subsynchronous oscillation signals and can be used to analyze the phase difference and oscillation synchronization characteristics between different signals.

[0010] Optionally, S1 also includes oscillation frequency significance analysis, including correlation analysis between load fluctuation and oscillation frequency, and correlation analysis between excitation state and oscillation frequency. The significance of oscillation frequency is judged through correlation analysis between load fluctuation, generator excitation state and subsynchronous oscillation frequency to avoid misjudgment.

[0011] Optionally, the S2 specifically includes: S21, signal separation: The center frequency is extracted by filtering. Nearby signals , to focus on the oscillation characteristics within the target frequency range; S22, Time-Varying Frequency Analysis: Use time-varying analysis algorithms to Perform time-frequency decomposition to obtain the time-frequency distribution of the signal : ,in, is the input time domain signal in The value of the moment, It is a time window function, which is used to intercept signals in a short period of time for frequency analysis and focus on signals in a short period of time. is a complex exponential term used to extract the frequency The corresponding weight; S23, Time-varying analysis of oscillation frequency: In the time-frequency distribution Find each time point The frequency component with the largest energy : represents the change of oscillation frequency over time; S24, Time-varying analysis of oscillation amplitude: For each time point ,calculate The amplitude of the corresponding frequency component: represents the change of the oscillation amplitude of the subsynchronous oscillation signal over time; S25, Time-varying analysis of oscillation phase: For each time point ,calculate The phase of the corresponding frequency component: Represents the change of the phase of the subsynchronous oscillation signal over time.

[0012] Optionally, the S3 specifically includes: S31, taking the time-varying characteristics of the subsynchronous oscillation frequency signal as input, including: Time Variation of Oscillation Frequency , represents the dynamic change of subsynchronous frequency over time; Time Variation of Oscillation Amplitude , which represents the dynamic change of oscillation intensity over time; Time Variation of Oscillation Phase , which represents the dynamic change of the time position of the oscillation signal over time; S32, dynamic frequency compensation control: Based on the time-varying characteristics, the dynamic frequency compensation control algorithm is applied to correct the frequency suppression parameters in real time: ,in, is the corrected frequency suppression parameter, which is used to adjust the control action in real time. is the basic inhibition parameter; : Actual frequency deviation; : Oscillation amplitude deviation; : Oscillation phase deviation; : Represents the compensation gain coefficients of frequency, amplitude and phase respectively; S33, adaptive controller real-time adjustment: the corrected frequency suppression parameter Delivered to the adaptive controller in the subsynchronous oscillation suppression device.

[0013] Optionally, the adaptive controller adjusts the system output in real time according to the following principles: ,in, It is the output signal of the adaptive controller, which is used to control the generator excitation system and speed control system equipment. is the dynamic rate of change of the frequency suppression parameter, It is a nonlinear mapping function that converts the frequency suppression parameter and its dynamic change rate into the controller output signal .

[0014] A control device for a subsynchronous oscillation suppression device, used to implement the control method for the subsynchronous oscillation suppression device, comprises the following units: Operation status monitoring unit: used to collect data on grid frequency, load fluctuation, generator speed and generator excitation status, and identify subsynchronous oscillation frequency signals based on the collected data; A time-varying characteristic analysis unit: used to analyze the subsynchronous oscillation frequency signal through a time-varying analysis algorithm to extract the time-varying property of the oscillation frequency, the time-varying property of the oscillation amplitude and the time-varying property of the oscillation phase; Dynamic compensation control unit: used to apply dynamic frequency compensation control algorithm according to time-varying characteristics and correct frequency suppression parameters; Adaptive control unit: used to adjust the system output in real time based on the corrected frequency suppression parameters, and apply control signals to the execution units of the system to suppress subsynchronous oscillations.

[0015] Beneficial effects of the present invention: The present invention can accurately extract the subsynchronous frequency component and its main characteristics (including main frequency, amplitude and phase) through time-frequency analysis technology (such as short-time Fourier transform, wavelet transform, etc.), and combine the multi-dimensional dynamic characteristic parameters. The control system can accurately identify the significance of oscillations, and dynamically adjust the control signal based on real-time feedback through an adaptive controller to ensure the effectiveness and stability of the suppression strategy when the oscillation characteristics change. Especially when the oscillation frequency drifts and the oscillation amplitude fluctuates, the introduction of the dynamic frequency compensation algorithm avoids the limitations of the traditional fixed frequency assumption and greatly reduces the risk of misjudgment and insufficient suppression.

[0016] The present invention monitors the operating status data such as the grid frequency, generator speed, load fluctuation, excitation status, etc. in real time, and combines the time-varying analysis algorithm to accurately extract the time-varying characteristics of the oscillation frequency, oscillation amplitude and oscillation phase of the subsynchronous oscillation signal, dynamically captures the frequency drift and oscillation amplitude changes in the system, and corrects the frequency suppression parameters in real time through the dynamic frequency compensation control algorithm, so that the system can quickly respond to the dynamic changes of the subsynchronous oscillation when the frequency drifts, the load fluctuates violently or the system topology changes, thereby significantly improving the adaptability to the dynamic environment of the complex power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic diagram of a control method flow chart of an embodiment of the present invention; Figure 2 Schematic diagram of a control device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. At the same time, it is explained here that in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments, and those skilled in the art may also adopt other alternatives to implement some known technologies; and the accompanying drawings are only for more specific description of the embodiments, and are not intended to specifically limit the present invention.

[0020] It should be noted that the references to "one embodiment", "embodiment", "exemplary embodiments", "some embodiments" and the like in the specification indicate that the embodiments described may include specific features, structures or characteristics, but not every embodiment may include the specific features, structures or characteristics. In addition, when a specific feature, structure or characteristic is described in conjunction with an embodiment, it should be within the knowledge of a person skilled in the art to implement such feature, structure or characteristic in conjunction with other embodiments (whether or not explicitly described).

[0021] In general, a term can be understood, at least in part, from its use in context. For example, depending, at least in part, on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in the singular sense, or can be used to describe a combination of features, structures, or characteristics in the plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey an exclusive set of factors, but can instead, depending, at least in part, on the context, allow for the presence of other factors that are not necessarily explicitly described.

[0022] like Figure 1 As shown, the control method of the subsynchronous oscillation suppression device includes the following steps: S1: Real-time monitoring of the operating status data of the power system, collecting grid frequency, load fluctuation, generator speed, and generator excitation status, and identifying subsynchronous oscillation frequency signals in the power system based on real-time operating status data. The subsynchronous oscillation frequency signals include oscillation frequency, oscillation amplitude, and oscillation phase; S2: Analyze the time-varying characteristics of the subsynchronous oscillation frequency signal through a time-varying analysis algorithm. The time-varying characteristics include the time-varying property of the oscillation frequency, the time-varying property of the oscillation amplitude, and the time-varying property of the oscillation phase; S3: According to the time-varying characteristics, the dynamic frequency compensation control algorithm is applied to correct the frequency suppression parameters. Through the adaptive controller in the subsynchronous oscillation suppression device, real-time adjustments are made based on the corrected frequency suppression parameters, and control is applied in real time to suppress subsynchronous oscillations and avoid misjudgment of the oscillation frequency or failure to suppress it in time.

[0023] In S1, a sensor network installed at each node of the power system is used to collect data on real-time grid frequency, load fluctuation, generator speed, and generator excitation status. The sensor network includes: Voltage sensors are used to measure grid frequency , current sensors are used to measure load fluctuations The generator has a built-in speed sensor and excitation current sensor to measure the generator speed. , Generator excitation state ; Grid frequency calculation: using voltage signals collected by voltage sensors , calculate the frequency: ,in, is the period of the voltage signal. The zero point (positive and negative alternating point) is used to determine the period ,Right now: ,in, is the voltage signal at The time point of the zero crossing, is the grid frequency; Calculation of load fluctuations: Collect load current signals through current sensors , calculate the load fluctuation: ,in, is the instantaneous active power fluctuation of the load, is the instantaneous value of voltage, is the instantaneous value of current, is the phase angle between voltage and current, Calculated by the phase detection algorithm: , is the average active power of the load, and are the effective values ​​of voltage and current respectively; Calculation of generator speed: Calculate the speed using the speed pulse signal measured by the generator speed sensor: ,in, is the generator speed, is the pulse frequency output by the sensor, is the number of pole pairs of the generator; Calculation of excitation state: Collect excitation current signal through excitation current sensor , calculate its mean and fluctuation range: ; ; in, is the average value of the excitation current, is the fluctuation amplitude of the excitation current, is the length of the measurement time window.

[0024] The oscillation frequency is obtained based on the analysis of the operating status data, and the collected grid frequency is analyzed using Fourier transform. and generator speed Perform frequency analysis on the signal to obtain the spectrum: ,in, is the spectrum of the signal, indicating the frequency The amplitude, is the input signal, e.g. or ,express The grid frequency and generator speed at the moment, is the frequency component, and the oscillation frequency below the grid fundamental frequency is identified through the spectrum diagram , that is, the conditions are met: .

[0025] The oscillation amplitude is extracted from the spectrogram and is expressed as: ,in, This is the subsynchronization frequency The complex spectrum value at and are the real and imaginary parts of the spectrum value, It is the oscillation amplitude of the signal at the subsynchronous frequency, indicating the strength of the oscillation.

[0026] The oscillation phase describes the time position of the subsynchronous oscillation frequency signal and is expressed as: ,in, is the oscillation frequency The corresponding oscillation phase, phase It indicates the relative time position of subsynchronous oscillation signals and can be used to analyze the phase difference and oscillation synchronization characteristics between different signals.

[0027] S1 also includes oscillation frequency significance analysis, including correlation analysis between load fluctuation and oscillation frequency, and correlation analysis between excitation state and oscillation frequency. Through correlation analysis between load fluctuation, generator excitation state and subsynchronous oscillation frequency, the significance of oscillation frequency is judged to avoid misjudgment.

[0028] Correlation analysis between load fluctuation and subsynchronous oscillation frequency: The periodicity and subsynchronous oscillation frequency Analyze the correlation: ,in, is the correlation coefficient between the load fluctuation signal and the subsynchronous oscillation frequency signal, if Threshold value (such as 0.8) indicates that the subsynchronous oscillation signal is significant; Correlation analysis between excitation state and subsynchronous oscillation frequency: Subsynchronous oscillation frequency Perform similarity analysis and use cross power spectrum calculation: ,in, is the cross power spectrum of the excitation state signal and the subsynchronous oscillation frequency signal, is the spectrum of the excitation state signal, It is the conjugate spectrum of the subsynchronous oscillation frequency signal. If the amplitude of the cross power spectrum is significant near the subsynchronous oscillation frequency, it indicates that the subsynchronous oscillation signal is significant.

[0029] S2 specifically includes: S21, signal separation: The center frequency is extracted by filtering. Nearby signals , to focus on the oscillation characteristics within the target frequency range; S22, Time-Varying Frequency Analysis: Use time-varying analysis algorithms to Perform time-frequency decomposition to obtain the time-frequency distribution of the signal : ,in, is the input time domain signal in The value of the moment, It is a time window function, which is used to intercept signals in a short period of time for frequency analysis and focus on signals in a short period of time. is a complex exponential term used to extract the frequency The corresponding weight; S23, Time-varying analysis of oscillation frequency: In the time-frequency distribution Find each time point The frequency component with the largest energy : represents the change of oscillation frequency over time; S24, Time-varying analysis of oscillation amplitude: For each time point ,calculate The amplitude of the corresponding frequency component: represents the change of the oscillation amplitude of the subsynchronous oscillation signal over time; S25, Time-varying analysis of oscillation phase: For each time point ,calculate The phase of the corresponding frequency component: Represents the change of the phase of the subsynchronous oscillation signal over time.

[0030] S3 specifically includes: S31, taking the time-varying characteristics of the subsynchronous oscillation frequency signal as input, including: Time Variation of Oscillation Frequency , represents the dynamic change of subsynchronous frequency over time; Time Variation of Oscillation Amplitude , which represents the dynamic change of oscillation intensity over time; Time Variation of Oscillation Phase , which represents the dynamic change of the time position of the oscillation signal over time; S32, dynamic frequency compensation control: Based on the time-varying characteristics, the dynamic frequency compensation control algorithm is applied to correct the frequency suppression parameters in real time: ,in, is the corrected frequency suppression parameter, which is used to adjust the control action in real time. is the basic inhibition parameter; : Actual frequency deviation; : Oscillation amplitude deviation; : Oscillation phase deviation; : Represents the compensation gain coefficients of frequency, amplitude and phase respectively; S33, adaptive controller real-time adjustment: the corrected frequency suppression parameter Delivered to the adaptive controller in the subsynchronous oscillation suppression device.

[0031] The adaptive controller adjusts the system output in real time according to the following principles: ,in, It is the output signal of the adaptive controller, which is used to control the generator excitation system and speed control system equipment. is the dynamic rate of change of the frequency suppression parameter, It is a nonlinear mapping function that converts the frequency suppression parameter and its dynamic change rate into the controller output signal ; expressed as: ; : Static gain coefficient, used to adjust the response sensitivity of the controller to the current frequency suppression parameter; : Dynamic gain coefficient, used to adjust the controller's response sensitivity to the rate of change of the frequency suppression parameter.

[0032] like Figure 2 As shown, the control device of the subsynchronous oscillation suppression device is used to implement the control method of the subsynchronous oscillation suppression device, and includes the following units: Operation status monitoring unit: used to collect data on grid frequency, load fluctuation, generator speed and generator excitation status, and identify subsynchronous oscillation frequency signals based on the collected data; A time-varying characteristic analysis unit: used to analyze the subsynchronous oscillation frequency signal through a time-varying analysis algorithm to extract the time-varying property of the oscillation frequency, the time-varying property of the oscillation amplitude and the time-varying property of the oscillation phase; Dynamic compensation control unit: used to apply dynamic frequency compensation control algorithm according to time-varying characteristics and correct frequency suppression parameters; Adaptive control unit: used to adjust the system output in real time based on the corrected frequency suppression parameters, and apply control signals to the execution units of the system to suppress subsynchronous oscillations.

[0033] The present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention. In order to make the public have a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention, but those skilled in the art can fully understand the present invention without the description of these details. In addition, in order to avoid unnecessary confusion about the essence of the present invention, well-known methods, processes, procedures, components and circuits are not described in detail.

[0034] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A control method for a subsynchronous oscillation suppression device, characterized in that: The following steps are involved: S1: Real-time monitoring of the operating status data of the power system, collecting grid frequency, load fluctuation, generator speed, and generator excitation status, and identifying subsynchronous oscillation frequency signals in the power system based on real-time operating status data. The subsynchronous oscillation frequency signals include oscillation frequency, oscillation amplitude, and oscillation phase; S2: Analyze the time-varying characteristics of the subsynchronous oscillation frequency signal through a time-varying analysis algorithm. The time-varying characteristics include the time-varying property of the oscillation frequency, the time-varying property of the oscillation amplitude, and the time-varying property of the oscillation phase; S3: According to the time-varying characteristics, a dynamic frequency compensation control algorithm is applied to correct the frequency suppression parameters. Through the adaptive controller in the subsynchronous oscillation suppression device, real-time adjustments are made based on the corrected frequency suppression parameters, and control is applied in real time to suppress subsynchronous oscillations.

2. The control method of the subsynchronous oscillation suppression device according to claim 1, characterized in that: In S1, a sensor network installed at each node of the power system is used to collect data on real-time grid frequency, load fluctuation, generator speed and generator excitation state. The sensor network includes: Voltage sensors are used to measure grid frequency , current sensors are used to measure load fluctuations The generator has a built-in speed sensor and excitation current sensor to measure the generator speed. , Generator excitation state .

3. The control method of the subsynchronous oscillation suppression device according to claim 2, characterized in that: The oscillation frequency is obtained based on the analysis of the operating status data, and the collected grid frequency is analyzed using Fourier transform. and generator speed Perform frequency analysis on the signal to obtain the spectrum: ,in, is the spectrum of the signal, indicating the frequency The amplitude, is the input signal, is the frequency component, and the oscillation frequency below the grid fundamental frequency is identified through the spectrum diagram , that is, the conditions are met: .

4. The control method of the subsynchronous oscillation suppression device according to claim 3, characterized in that: The oscillation amplitude is extracted from the spectrogram and is expressed as: ,in, This is the subsynchronization frequency The complex spectrum value at and are the real and imaginary parts of the spectrum value, It is the oscillation amplitude of the signal at the subsynchronous frequency, indicating the strength of the oscillation.

5. The control method of the subsynchronous oscillation suppression device according to claim 4, characterized in that: The oscillation phase describes the time position of the subsynchronous oscillation frequency signal and is expressed as: ,in, is the oscillation frequency The corresponding oscillation phase.

6. The control method of the subsynchronous oscillation suppression device according to claim 1, characterized in that: The S1 also includes oscillation frequency significance analysis, including correlation analysis between load fluctuation and oscillation frequency, and correlation analysis between excitation state and oscillation frequency. The significance of oscillation frequency is determined by correlation analysis between load fluctuation, generator excitation state and subsynchronous oscillation frequency.

7. The control method of the subsynchronous oscillation suppression device according to claim 1, characterized in that: The S2 specifically includes: S21, signal separation: The center frequency is extracted by filtering. Nearby signals , to focus on the oscillation characteristics within the target frequency range; S22, Time-Varying Frequency Analysis: Use time-varying analysis algorithms to Perform time-frequency decomposition to obtain the time-frequency distribution of the signal : ,in, is the input time domain signal in The value of the moment, is the time window function, is a complex exponential term; S23, Time-varying analysis of oscillation frequency: In the time-frequency distribution Find each time point The frequency component with the largest energy : represents the change of oscillation frequency over time; S24, Time-varying analysis of oscillation amplitude: For each time point ,calculate The amplitude of the corresponding frequency component: represents the change of the oscillation amplitude of the subsynchronous oscillation signal over time; S25, Time-varying analysis of oscillation phase: For each time point ,calculate The phase of the corresponding frequency component: Represents the change of the phase of the subsynchronous oscillation signal over time.

8. The control method of the subsynchronous oscillation suppression device according to claim 7, characterized in that: The S3 specifically includes: S31, taking the time-varying characteristics of the subsynchronous oscillation frequency signal as input, including: Time Variation of Oscillation Frequency , represents the dynamic change of subsynchronous frequency over time; Time Variation of Oscillation Amplitude , which represents the dynamic change of oscillation intensity over time; Time Variation of Oscillation Phase , which represents the dynamic change of the time position of the oscillation signal over time; S32, dynamic frequency compensation control: Based on the time-varying characteristics, the dynamic frequency compensation control algorithm is applied to correct the frequency suppression parameters in real time: ,in, is the corrected frequency suppression parameter, which is used to adjust the control action in real time. is the basic inhibition parameter; : Actual frequency deviation; : Oscillation amplitude deviation; : Oscillation phase deviation; : Represents the compensation gain coefficients of frequency, amplitude and phase respectively; S33, adaptive controller real-time adjustment: the corrected frequency suppression parameter Delivered to the adaptive controller in the subsynchronous oscillation suppression device.

9. The control method of the subsynchronous oscillation suppression device according to claim 8, characterized in that: The adaptive controller adjusts the system output in real time according to the following principles: ,in, It is the output signal of the adaptive controller, which is used to control the generator excitation system and speed control system equipment. is the dynamic rate of change of the frequency suppression parameter, It is a nonlinear mapping function that converts the frequency suppression parameter and its dynamic change rate into the controller output signal .

10. A control device for a subsynchronous oscillation suppression device, used to implement a control method for a subsynchronous oscillation suppression device according to any one of claims 1 to 9, characterized in that: The following units are included: Operation status monitoring unit: used to collect data on grid frequency, load fluctuation, generator speed and generator excitation status, and identify subsynchronous oscillation frequency signals based on the collected data; A time-varying characteristic analysis unit: used to analyze the subsynchronous oscillation frequency signal through a time-varying analysis algorithm to extract the time-varying property of the oscillation frequency, the time-varying property of the oscillation amplitude and the time-varying property of the oscillation phase; Dynamic compensation control unit: used to apply dynamic frequency compensation control algorithm according to time-varying characteristics and correct frequency suppression parameters; Adaptive control unit: used to adjust the system output in real time based on the corrected frequency suppression parameters, and apply control signals to the execution units of the system to suppress subsynchronous oscillations.

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