Reactive compensator control method and system based on offshore wind turbine generator

Abstract

The invention discloses a reactive power compensator control method and system based on an offshore wind turbine generator, and relates to the technical field of reactive power compensator control, and the method comprises the following steps: obtaining the operation data of a reactive power compensator of an offshore wind turbine generator; calculating reactive power required to be compensated for by the reactive power compensator according to the operation data, performing outer loop control on the reactive power compensator by using the reactive power required to be compensated, and converting the reactive power required to be compensated for into a reference voltage signal of the reactive power compensator; using a second-order generalized integrator and a quasi-proportional resonance controller to generate a circulating current suppression signal of the reactive power compensator to carry out inner loop control; performing weighted calculation on the circulating current suppression signal and the reference voltage signal by using a dynamic weight distribution mechanism, and generating a control signal of the reactive power compensator; and controlling the reactive power compensator based on the control signal.

Description

Technical Field

[0001] This invention relates to the field of reactive power compensator control technology, and mainly to a control method and system for reactive power compensators based on offshore wind turbines. Background Technology

[0002] As the global energy structure shifts towards cleaner and lower-carbon energy, offshore wind turbines have become an important development direction in the field of new energy power due to their high power generation efficiency, abundant resources, and environmental friendliness. However, the large-scale grid connection of offshore wind power poses a severe challenge to grid stability, especially the problems of grid voltage regulation and dynamic reactive power management, which urgently need to be solved.

[0003] Offshore wind farms are typically connected to the onshore power grid via long-distance submarine cables. The distributed capacitance of these cables generates significant charging power, which, combined with the strong fluctuations in wind turbine output due to natural conditions, results in frequent and substantial changes in the system's reactive power demand. Furthermore, reactive power losses within the offshore wind turbine's internal equipment (such as converters and transformers) further exacerbate grid voltage fluctuations. Traditional reactive power compensation technologies for onshore power grids, lacking specific design considerations for the complex offshore environment, are ill-suited to effectively address these issues.

[0004] Currently, existing control strategies mostly employ a single mode (such as constant voltage or constant reactive power control), lacking a dynamic switching mechanism and failing to adapt to the differentiated needs of various operating scenarios (such as normal operation, voltage anomalies, and emergency faults). For example, when voltage fluctuates drastically, the constant reactive power mode cannot quickly adjust compensation commands to stabilize the voltage; while during steady-state operation, the constant voltage mode may suffer from insufficient circulating current suppression due to overcompensation. Furthermore, traditional methods have limited effectiveness in suppressing circulating currents generated during the operation of modular multilevel converters. The second harmonic and high-frequency even-order harmonic components in the circulating current of modular multilevel converters significantly increase arm losses, causing current distortion and reducing system efficiency and power quality; existing circulating current suppression technologies (such as simple filtering or proportional-integral control) struggle to accurately separate the DC and AC components of the circulating current, and are prone to control parameter mismatch problems in complex harmonic environments.

[0005] In summary, there is an urgent need for a reactive power compensation control method that can dynamically coordinate voltage stability and circulating current suppression, adapt to multi-mode switching, and has efficient sub-module management capabilities, in order to improve the grid connection stability and operational economy of offshore wind turbines. Summary of the Invention

[0006] To address the aforementioned problems in the existing technology, this application provides a control method and system based on a reactive power compensator for offshore wind turbines.

[0007] The technical solution of this application is as follows: On the one hand, a control method based on a reactive power compensator for an offshore wind turbine, the method comprising: Obtain operational data of the reactive power compensator of offshore wind turbines; The reactive power that the reactive power compensator needs to compensate is calculated based on the operating data. The reactive power that needs to be compensated is used to perform outer loop control on the reactive power compensator, and the reactive power that needs to be compensated is converted into a reference voltage signal for the reactive power compensator. The circulating current suppression signal of the reactive power compensator is generated by using a second-order generalized integrator and a quasi-proportional resonant controller for inner-loop control. The circulating current suppression signal and the reference voltage signal are calculated by weighting them using a dynamic weighting allocation mechanism to generate the control signal for the reactive power compensator. The reactive power compensator is controlled based on the control signal.

[0008] Preferably, the reactive power to be compensated includes the reactive power loss of the wind power equipment itself, the charging power compensation of the submarine cable, and the dynamic fluctuation gap, wherein: The reactive power loss of the wind power equipment itself can be expressed by the formula: ; In the formula, This indicates the reactive power loss of the wind power equipment itself; Indicates the first The active power of the typhoon generator; Indicates the first The power factor tangent of a typhoon generator; Indicates the first The index value of the typhoon generator; Indicates the number of fans; The submarine cable charging power compensation is expressed by the formula: ; In the formula, This indicates compensation for the charging power of the submarine cable; Indicates the operating voltage of the submarine cable; Indicates the angular frequency at which the submarine cable operates; This represents the capacitance per unit length of the submarine cable; Indicates the length of the submarine cable; The dynamic fluctuation gap is expressed by the formula: ; In the formula, Indicates a dynamic fluctuation gap; Indicates the first weighting coefficient; This represents the second weighting coefficient; This indicates the change in the active power of the wind turbine; Indicates the voltage deviation at the grid connection point; The reactive power that needs to be compensated is expressed by the formula: ; In the formula, This indicates the reactive power that needs to be compensated.

[0009] Preferably, the circulating current suppression signal of the reactive power compensator is generated using a second-order generalized integrator and a quasi-proportional resonant controller for inner-loop control, specifically as follows: The circulating current component is extracted using a second-order generalized integrator. Specifically, the original circulating current flowing through the reactive power compensator is input into the second-order generalized integrator to extract the second harmonic AC component. The difference between the second harmonic AC component and the original circulating current is calculated to obtain an error signal, wherein the error signal includes the high-frequency even harmonic component and the DC component of the circulating current. The error signal is input into a DC integrator to filter out the high-frequency even-order harmonic components in the error signal and extract the DC component. Subtract the extracted DC component from the original circulating current to obtain the AC component containing the second harmonic and high-frequency even orders. The AC components, including the second harmonic and high-frequency even-order components, are input into a quasi-proportional resonant controller to generate a circulating current suppression signal.

[0010] Preferably, the circulating current suppression signal and the reference voltage signal are calculated using a dynamic weight allocation mechanism, specifically as follows: Set voltage stability weights and circulating current suppression weights, and dynamically adjust the voltage stability weights and circulating current suppression weights according to the grid connection point voltage and the standard voltage; If the difference between the grid connection point voltage and the standard voltage exceeds the preset range, the voltage stability weight is increased, and the outer loop control generates a new reference voltage signal for reactive power compensation. Otherwise, increase the circulating current suppression weight and adjust the filtering bandwidth of the second-order generalized integrator to generate a new circulating current suppression signal for circulating current suppression.

[0011] On the other hand, the present invention also provides a sorting method for reactive power compensator submodules based on an improved jump sorting algorithm, the method comprising: An improved jump sorting algorithm is used to sort the sub-modules of the reactive power compensator, resulting in a sorted sequence of sub-modules. The charging and discharging order of submodules is controlled based on the sorted submodule sequence.

[0012] Preferably, the sub-modules of the reactive power compensator are sorted using an improved jump sorting algorithm, specifically as follows: The capacitor voltage of each submodule is collected in real time, and the extreme difference of the capacitor voltage of all submodules is calculated. The extreme difference is dynamically thresholded as follows: when the extreme difference is greater than the upper limit of the preset capacitor voltage reference value, the sorting operation is triggered; when the extreme difference is less than the lower limit of the preset capacitor voltage reference value, the sorting operation is stopped. The sorting operation specifically involves initializing the number of sub-modules, the scan endpoint, and the last swap position, performing inner and outer loop control; comparing the capacitor voltage of the current sub-module with the capacitor voltage of the next sub-module of the current sub-module, swapping the positions of the two sub-modules based on the comparison result, and updating the last swap position to the position of the current sub-module; at the end of each inner loop, updating the scan endpoint to the last swap position. If no submodules are swapped after one inner loop, the sorting is complete, the loop stops, and the sorted submodule sequence is output.

[0013] Preferably, the charging and discharging order of the submodules is controlled based on the sorted submodule sequence, specifically as follows: When the reactive power compensator is in the charging phase, it charges the sub-modules whose capacitor voltage is less than the preset charging threshold. When the reactive power compensator is in the discharge phase, it discharges the sub-modules whose capacitor voltage is greater than the preset discharge threshold.

[0014] On the other hand, the present invention also proposes a control system based on a reactive power compensator for offshore wind turbines, the system comprising a data acquisition module, a control signal generation module, and a control module, wherein: The data acquisition module is used to acquire the operating data of the reactive power compensator of the offshore wind turbine; and transmit the operating data to the control signal generation module. The control signal generation module is used to calculate the reactive power that the reactive power compensator needs to compensate based on the operating data, and to use the reactive power that needs to be compensated to perform outer loop control on the reactive power compensator, converting the reactive power that needs to be compensated into a reference voltage signal for the reactive power compensator. The circulating current suppression signal of the reactive power compensator is generated by using a second-order generalized integrator and a quasi-proportional resonant controller for inner-loop control. The circulating current suppression signal and the reference voltage signal are calculated by weighting them using a dynamic weight allocation mechanism to generate the control signal for the reactive power compensator. The control module is used to control the reactive power compensator based on the control signal.

[0015] In another aspect, the present invention also proposes an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement a control method for a reactive power compensator based on an offshore wind turbine as described in the present invention.

[0016] Furthermore, the present invention also proposes a computer-readable storage medium storing a computer program that, when executed by a processor, implements a control method for a reactive power compensator based on an offshore wind turbine as described in the present invention.

[0017] Compared with the prior art, the beneficial effects of the present invention are: 1) This invention provides a control method and system for reactive power compensators based on offshore wind turbines. By acquiring the operating data of the reactive power compensator and calculating the reactive power that needs to be compensated, dynamic response to compensation demand is achieved. The calculated reactive power is used for outer loop control and converted into a reference voltage signal, thereby enabling the compensator to adjust its output in real time, effectively improving the accuracy and timeliness of reactive power compensation. 2) This invention provides a control method and system for reactive power compensators based on offshore wind turbines. By introducing a second-order generalized integrator and a quasi-proportional resonant controller, the reactive power compensator is subjected to fine inner-loop control, which improves the accuracy of the system, ensures that the compensator can quickly and accurately track the reference signal, suppress the generation of circulating current, and enhance the stability of the system. 3) This invention provides a control method and system for reactive power compensators based on offshore wind turbines. It adopts a dynamic weight allocation mechanism to calculate the circulating current suppression signal and the reference voltage signal, which can optimize the control signal according to the real-time status of the system, ensuring that the reactive power compensator responds more flexibly and efficiently, enhancing the adaptability and robustness of the control system, and effectively coping with fluctuations in system load and environment. Attached Figure Description

[0018] Figure 1 This is a flowchart of a method according to an embodiment of the present invention; Figure 2 This is a framework diagram of a second-order generalized integrator according to an embodiment of the present invention; Figure 3 This is a diagram illustrating the circulating current suppression effect of the reactive power compensator according to an embodiment of the present invention; Figure 4 This is a comparison chart of the sub-module sorting algorithms in an embodiment of the present invention. Detailed Implementation

[0019] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0020] This invention provides the following technical solution: a control method and system based on a reactive power compensator for offshore wind turbines.

[0021] Example 1 See details Figure 1 This embodiment provides a control method based on the reactive power compensator of an offshore wind turbine, the specific steps of which include: In this embodiment, the reactive power compensator is a modular multilevel converter. The modular multilevel converter adopts a modular design concept. By adjusting the number of its internal series sub-modules, it can flexibly adapt to different voltage and power level requirements. S1. Obtain the operating data of the reactive power compensator of the offshore wind turbine; The method further includes data cleaning of the running data, which includes handling missing values, outliers, and data format standardization. S2. Calculate the reactive power that the reactive power compensator needs to compensate based on the operating data, and use the reactive power that needs to be compensated to perform outer loop control on the reactive power compensator, converting the reactive power that needs to be compensated into a reference voltage signal for the reactive power compensator. S21. The reactive power to be compensated includes the reactive power loss of the wind power equipment itself, the charging power compensation of the submarine cable, and the dynamic fluctuation gap, wherein: S211. The reactive power loss of the wind power equipment itself is expressed by the formula: ; In the formula, This indicates the reactive power loss of the wind power equipment itself; Indicates the first The active power of the typhoon generator; Indicates the first The power factor tangent of a typhoon generator; Indicates the first The index value of the typhoon generator; Indicates the number of fans; S212. The submarine cable charging power compensation is expressed by the formula: ; In the formula, This indicates compensation for the charging power of the submarine cable; Indicates the operating voltage of the submarine cable; Indicates the angular frequency at which the submarine cable operates; This represents the capacitance per unit length of the submarine cable; Indicates the length of the submarine cable; S213. The aforementioned dynamic fluctuation gap is expressed by the formula: ; In the formula, Indicates a dynamic fluctuation gap; Indicates the first weighting coefficient; This represents the second weighting coefficient; This indicates the change in the active power of the wind turbine; Indicates the voltage deviation at the grid connection point; S22. The reactive power that needs to be compensated is expressed by the formula: ; In the formula, This indicates the reactive power that needs to be compensated. S23. Set the trigger conditions for different control modes, including constant voltage mode, constant reactive power mode and emergency mode. In this embodiment, the triggering condition in the constant voltage mode is specifically when the voltage deviation at the grid connection point exceeds ±5% of the preset rated value; The specific triggering condition for the constant reactive power mode is that the voltage deviation at the grid connection point is less than ±2% of the preset rated value; The specific triggering conditions in the emergency mode are when the voltage deviation at the grid connection point exceeds ±10% of the preset rated value or when the AC frequency of the grid at the grid connection point exceeds the upper or lower limit of the preset AC frequency. In this embodiment, the upper limit of the preset AC frequency is 51Hz, and the lower limit of the preset AC frequency is 49Hz. S24. Based on the reactive power to be compensated and the triggering conditions corresponding to different control modes, calculate the reference voltage signal of the reactive power compensator under different control modes. The reference voltage signal of the reactive power compensator in constant voltage mode is expressed by the formula: ; In the formula, Indicates the reference voltage signal; Indicates standard voltage; This indicates the preset scaling factor; Indicates the preset integral coefficient; Indicates the voltage at the grid connection point; Indicates the reactive power-to-voltage conversion factor; This represents the actual reactive power. The reference voltage signal of the reactive power compensator in constant reactive power mode is expressed by the formula: ; In emergency mode, the reactive power compensator directly outputs the maximum capacitive or inductive reactive power. Specifically, when the grid connection point voltage is lower than -10% of the preset rated value, the reactive power compensator outputs inductive reactive power to help boost the voltage; when the grid connection point voltage exceeds +10% of the preset rated value, the reactive power compensator outputs capacitive reactive power to absorb excess reactive power and reduce the voltage. The response time for the emergency mode is <10ms; S3, please see Figure 2 The circulating current suppression signal of the reactive power compensator is generated by using a second-order generalized integrator and a quasi-proportional resonant controller for inner-loop control; The circulating current flowing through each phase of the modular multilevel converter consists of two parts: a DC component and an AC component. The DC component is responsible for balancing the three-phase power and plays an indispensable role in the active power transmission process, so there is no need to suppress it. However, during the operation of the modular multilevel converter, the AC component causes a significant increase in arm losses, which in turn causes distortion in the arm current. This current distortion not only negatively affects the normal operation of the arm but also seriously damages the quality of current and voltage, threatening the stable operation of the entire system. The circulation of each phase is expressed by the following formula: ; ; ; In the formula, express Phase circulation; Represents the DC component current; Indicates the first Index value of the secondary circulation; Indicates the first Harmonic peak values ​​of the alternating current component in the secondary circulation; Represents the resonant angular frequency of the AC component; Represents a time variable; Indicates the first The initial phase of the harmonics of the AC component in the secondary circulation; express Phase circulation; express Phase circulation; S31. Extract the circulating current component using a second-order generalized integrator. Specifically, input the original circulating current flowing through the reactive power compensator into the second-order generalized integrator to extract the second harmonic AC component. Calculate the difference between the second harmonic AC component and the original circulating current to obtain an error signal, wherein the error signal includes the high-frequency even-order harmonic component and the DC component of the circulating current. The error signal is input into a DC integrator to filter out the high-frequency even-order harmonic components in the error signal and extract the DC component. Subtracting the extracted DC component from the original circulating current yields the AC component, which includes the second harmonic and high-frequency even orders, expressed by the formula: , ; In the formula, Indicates the first The alternating component of the phase circulation; Indicates the first Phase circulation; Represents the control constant; Represents the Laplace operator; This represents the angular frequency of the second-order generalized integrator; Indicates the first The index value of the phase circulation; In this embodiment, the angular frequency of the second-order generalized integrator is fixed at . ; S32. The AC components containing the second harmonic and high-frequency even-order components are input into a quasi-proportional resonant controller to generate a circulating current suppression signal, expressed by the formula: ; ; In the formula, Indicates the first Phase circulation suppression signal; The transfer function of the quasi-proportional resonant controller is represented. Indicates the resonance coefficient; Indicates the proportional gain coefficient; Indicates the cutoff angular frequency; Indicates the resonant angular frequency; The circulating current suppression signal needs to be achieved by adjusting the switching state of the reactive power compensator submodule to suppress the circulating current, and the voltage balancing of the reactive power compensator submodule can reduce the interference of circulating current harmonic components on the suppression effect. S4. Calculate the circulating current suppression signal and the reference voltage signal using a dynamic weight allocation mechanism to generate the control signal for the reactive power compensator. The control signal of the reactive power compensator is expressed by the formula: ; In the formula, This indicates the control signal for the reactive power compensator; Indicates voltage stability weight; Indicates the circulation suppression weight; Set voltage stability weights and circulating current suppression weights, and dynamically adjust the voltage stability weights and circulating current suppression weights according to the grid connection point voltage and the standard voltage; If the difference between the grid connection point voltage and the standard voltage exceeds the preset range, the voltage stability weight is increased, and the outer loop control generates a new reference voltage signal for reactive power compensation. Otherwise, increase the circulating current suppression weight and adjust the filtering bandwidth of the second-order generalized integrator to make the inner loop control generate a new circulating current suppression signal for circulating current suppression; Specifically, this can be expressed as a formula: ; ; S5. Control the reactive power compensator based on the control signal; S6, please see Figure 3 In this embodiment, after the circulation suppression is activated at 0.3 seconds, the peak value and root mean square value of the circulation are significantly reduced, the steady-state residual is significantly reduced, and the convergence time is shortened.

[0022] Example 2: This embodiment provides a sorting method for reactive power compensator submodules based on an improved jump sorting algorithm, the specific steps of which include: In this embodiment, to improve the effect of reactive power compensator in circulating current suppression, an improved sorting algorithm is used to sort the sub-modules of reactive power compensator. The effect of circulating current suppression is improved by balancing the voltage of the sub-modules. Based on the sorted sub-modules, the reactive power compensator enhances the stability of maintaining output voltage, ensures reactive power compensation accuracy, and reduces bridge arm losses. T1. Use the improved jump sorting algorithm to sort the sub-modules of the reactive power compensator to obtain the sorted sub-module sequence; The charging and discharging order of sub-modules is controlled based on the sorted sub-module sequence; T11. Use an improved jump sorting algorithm to sort the submodules of the reactive power compensator, specifically: T111. Real-time acquisition of the capacitor voltage of each submodule, calculation of the extreme difference of capacitor voltages of all submodules, expressed as: ,in This indicates the upper limit of the capacitor voltage in the submodule. Indicates the lower limit of the capacitor voltage of the submodule; The dynamic threshold judgment of the range value is as follows: when the range value is greater than the preset upper limit of the capacitor voltage reference value, the sorting operation is triggered; when the range value is less than the preset lower limit of the capacitor voltage reference value, the sorting operation is stopped. In this embodiment, when When, a sorting operation is triggered, where This is the reference value for capacitor voltage; when Stop the sorting operation when the time comes; T112, The sorting operation specifically initializes the number of submodules. The scan endpoint is the position of the last sub-module, that is, the current scan endpoint is... The last swap position is -1; Perform inner and outer loop control, where the outer loop control specifically involves performing... Round-robin traversal; the inner loop control specifically involves each round of traversal, scanning from the first sub-module to the current scan endpoint; comparing the capacitor voltage of the current sub-module with the capacitor voltage of the next sub-module, if... This indicates the current submodule. capacitor voltage The next submodule that is greater than the current submodule capacitor voltage If the last swapped position is not found, the positions of the two submodules will be swapped, and the position of the last swapped position will be updated to the position of the current submodule. At the end of each inner loop, update the scan endpoint to the position of the last swap; If no submodules are swapped after one inner loop, the sorting is complete, the loop stops, and the sorted submodule sequence is output. T12. The charging and discharging order of the sub-modules is controlled based on the sorted sub-module sequence, specifically as follows: When the reactive power compensator is in the charging phase, it charges the sub-modules whose capacitor voltage is less than the preset charging threshold. When the reactive power compensator is in the discharge phase, the sub-modules whose capacitor voltage is greater than the preset discharge threshold will be discharged. T2, please refer to Figure 4 In this embodiment, after adjusting the sub-modules of the reactive power compensator using the improved jump algorithm, the extreme difference of the capacitor voltage of the sub-module is smaller than that of the sub-module capacitor voltage using traditional algorithms (such as bubble algorithm, quick sort algorithm, etc.) or without using an algorithm within the same sampling time. The smaller the extreme difference of the capacitor voltage of the submodule, the better the circulating current suppression effect of the reactive power compensator.

[0023] Example 3: This embodiment provides a control system based on a reactive power compensator for offshore wind turbines. The system includes a data acquisition module, a control signal generation module, and a control module, wherein: The data acquisition module is used to acquire the operating data of the reactive power compensator of the offshore wind turbine; and transmit the operating data to the control signal generation module. The control signal generation module is used to calculate the reactive power that the reactive power compensator needs to compensate based on the operating data, and to use the reactive power that needs to be compensated to perform outer loop control on the reactive power compensator, converting the reactive power that needs to be compensated into a reference voltage signal for the reactive power compensator. The circulating current suppression signal of the reactive power compensator is generated by using a second-order generalized integrator and a quasi-proportional resonant controller for inner-loop control. The circulating current suppression signal and the reference voltage signal are calculated by weighting them using a dynamic weight allocation mechanism to generate the control signal for the reactive power compensator. The control module is used to control the reactive power compensator based on the control signal.

[0024] Example 4: This embodiment provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements a control method for a reactive power compensator based on an offshore wind turbine as described in any embodiment of the present invention.

[0025] Example 5: This embodiment provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements a control method for a reactive power compensator based on an offshore wind turbine as described in any embodiment of the present invention.

[0026] It is worth noting that the system, electronic device, and computer-readable storage medium described in this invention are all based on the same principle as the method described in Embodiment 1, and will not be repeated here.

[0027] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A control method based on a reactive power compensator for offshore wind turbines, characterized in that, The method includes: Obtain operational data of the reactive power compensator of offshore wind turbines; The reactive power that the reactive power compensator needs to compensate is calculated based on the operating data. The reactive power that needs to be compensated is used to perform outer loop control on the reactive power compensator, and the reactive power that needs to be compensated is converted into a reference voltage signal for the reactive power compensator. The circulating current suppression signal of the reactive power compensator is generated by using a second-order generalized integrator and a quasi-proportional resonant controller for inner-loop control. The circulating current suppression signal and the reference voltage signal are calculated by weighting them using a dynamic weighting allocation mechanism to generate the control signal for the reactive power compensator. The reactive power compensator is controlled based on the control signal.

2. The control method for a reactive power compensator based on an offshore wind turbine according to claim 1, characterized in that, The reactive power to be compensated includes the reactive power loss of the wind power equipment itself, the power compensation for submarine cable charging, and the dynamic fluctuation gap, wherein: The reactive power loss of the wind power equipment itself can be expressed by the formula: ； In the formula, This indicates the reactive power loss of the wind power equipment itself; Indicates the first The active power of the typhoon generator; Indicates the first The power factor tangent of a typhoon generator; Indicates the first The index value of the typhoon generator; Indicates the number of fans; The submarine cable charging power compensation is expressed by the formula: ； In the formula, This indicates compensation for the charging power of the submarine cable; Indicates the operating voltage of the submarine cable; Indicates the angular frequency at which the submarine cable operates; This represents the capacitance per unit length of the submarine cable; Indicates the length of the submarine cable; The dynamic fluctuation gap is expressed by the formula: ； In the formula, Indicates a dynamic fluctuation gap; Indicates the first weighting coefficient; This represents the second weighting coefficient; This indicates the change in the active power of the wind turbine; Indicates the voltage deviation at the grid connection point; The reactive power that needs to be compensated is expressed by the formula: ； In the formula, This indicates the reactive power that needs to be compensated.

3. The control method based on the reactive power compensator of an offshore wind turbine according to claim 1, characterized in that, The reactive power compensator is subjected to inner-loop control using a second-order generalized integrator and a quasi-proportional resonant controller, specifically as follows: The circulating current component is extracted using a second-order generalized integrator. Specifically, the original circulating current flowing through the reactive power compensator is input into the second-order generalized integrator to extract the second harmonic AC component. The difference between the second harmonic AC component and the original circulating current is calculated to obtain an error signal, wherein the error signal includes the high-frequency even harmonic component and the DC component of the circulating current. The error signal is input into a DC integrator to filter out the high-frequency even-order harmonic components in the error signal and extract the DC component. Subtract the extracted DC component from the original circulating current to obtain the AC component containing the second harmonic and high-frequency even orders. The AC components, including the second harmonic and high-frequency even-order components, are input into a quasi-proportional resonant controller to generate a circulating current suppression signal.

4. The control method based on the reactive power compensator of an offshore wind turbine according to claim 1, characterized in that, The circulating current suppression signal and the reference voltage signal are calculated using a dynamic weighting mechanism, specifically as follows: Set voltage stability weights and circulating current suppression weights, and dynamically adjust the voltage stability weights and circulating current suppression weights according to the grid connection point voltage and the standard voltage; If the difference between the grid connection point voltage and the standard voltage exceeds the preset range, the voltage stability weight is increased, and the outer loop control generates a new reference voltage signal for reactive power compensation. Otherwise, increase the circulating current suppression weight and adjust the filtering bandwidth of the second-order generalized integrator to generate a new circulating current suppression signal for circulating current suppression.

5. A control system based on a reactive power compensator for offshore wind turbines, characterized in that, The system includes a data acquisition module, a control signal generation module, and a control module, wherein: The data acquisition module is used to acquire the operating data of the reactive power compensator of the offshore wind turbine; and transmit the operating data to the control signal generation module. The control signal generation module is used to calculate the reactive power that the reactive power compensator needs to compensate based on the operating data, and to use the reactive power that needs to be compensated to perform outer loop control on the reactive power compensator, converting the reactive power that needs to be compensated into a reference voltage signal for the reactive power compensator. The circulating current suppression signal of the reactive power compensator is generated by using a second-order generalized integrator and a quasi-proportional resonant controller for inner-loop control. The circulating current suppression signal and the reference voltage signal are calculated by weighting them using a dynamic weighting allocation mechanism to generate the control signal for the reactive power compensator. The control module is used to control the reactive power compensator based on the control signal.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements a control method for a reactive power compensator based on an offshore wind turbine as described in any one of claims 1 to 4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by the processor, the program implements a control method for a reactive power compensator based on an offshore wind turbine as described in any one of claims 1 to 4.

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