Method and system for monitoring scouring depth of foundation of offshore wind turbine generator

Abstract

The invention discloses a foundation scouring depth monitoring method and a foundation scouring depth monitoring system for an offshore wind turbine generator, and relates to the technical field of monitoring. Analyzing the relationship between the scouring depth safety value threshold value and the scouring rate of the offshore wind turbine generator set in different environments and states and each parameter of seawater, monitoring each information of the current offshore wind turbine generator set, judging the stability of the current offshore wind turbine generator set, if the stability is poor, performing early warning, and if the stability is good, performing early warning. If yes, whether maintenance early warning needs to be carried out or not is analyzed, if yes, parameters of current seawater are obtained, early warning levels of maintenance and the like of the offshore wind turbine generator are judged according to the parameters of the current seawater and the relation between the scouring rate and the parameters of the seawater, early warning is carried out, and the effectiveness of stability judgment of the offshore wind turbine generator is guaranteed; and the timeliness of maintenance of the offshore wind turbine generator is also ensured.

Description

Technical Field

[0001] The present invention relates to the field of monitoring technology, and in particular to a method and system for monitoring the scour depth of an offshore wind turbine foundation. Background Art

[0002] Offshore wind energy, as an important component of clean and renewable energy, is generated through offshore wind turbines. However, the foundations of offshore wind turbines are exposed to complex marine environments for a long time. Affected by hydrodynamic forces such as water scouring, wave impact, and tidal changes, the seabed sediment around the foundation is easily eroded and transported, forming scour pits, which leads to a reduction in foundation burial depth and structural stiffness, becoming a core hidden danger threatening the safety of offshore wind turbines.

[0003] The invention patent application with prior art announcement number CN119084250A discloses a method and system for monitoring the scour depth of offshore wind turbine foundations, which collects vibration accelerations at different positions of the offshore wind turbine in real time; filters and Fourier transforms the vibration accelerations at different positions of the offshore wind turbine collected in real time to obtain the natural frequency of the wind turbine; calculates the critical frequency of each offshore wind turbine in the offshore wind farm based on the natural frequency of the offshore wind turbine and the scour limit depth of the offshore wind turbine; calculates based on the natural frequency of the offshore wind turbine and the critical frequency of the offshore wind turbine, and predicts whether the scour depth of each offshore wind turbine in the offshore wind farm is within a safe range based on the calculation results. The present invention can establish a wind power plant pile foundation anti-scour time warning system, timely judge the scour depth of the offshore wind turbine, and ensure that the judgment result is accurate, thereby ensuring the long-term safe and stable operation of the offshore wind farm.

[0004] In response to the above scheme, the applicant of the present invention found that the above technology has at least the following technical problems: 1. The offshore wind turbine foundation scour depth monitoring method and system are calculated based on the natural frequency of the offshore wind turbine and the critical frequency of the offshore wind turbine, and based on the calculation results, it is predicted whether the scour depth of each offshore wind turbine in the offshore wind farm is within the safe range. The influence of the environment and the status of the offshore wind turbine on the scour depth safety value threshold of the offshore wind turbine is lacking, and therefore the effectiveness of the offshore wind turbine stability judgment cannot be guaranteed.

[0005] 2. The offshore wind turbine foundation scour depth monitoring method and system lacks analysis of offshore wind turbine maintenance early warning. It only determines whether the current offshore wind turbine scour depth is safe. When the offshore wind turbine scour depth approaches the scour depth safety value threshold, no early warning can be issued, and thus the timeliness of offshore wind turbine maintenance cannot be guaranteed. Summary of the Invention

[0006] In view of the above-mentioned technical deficiencies, the object of the present invention is to provide a method and system for monitoring the scour depth of offshore wind turbine foundations.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions: In the first aspect, the present invention provides a method for monitoring the scour depth of the foundation of an offshore wind turbine, comprising the following steps: S1, data monitoring: monitoring the current environment of the offshore wind turbine, and monitoring various parameters of the offshore wind turbine and various parameters of the seawater.

[0008] S2. Data analysis: The stability of the offshore wind turbines at each historical monitoring time is obtained from the database, and a line graph is made according to the stability of the offshore wind turbines at each historical monitoring time in chronological order. Based on the line graph and the environment in which the offshore wind turbines are located at each historical monitoring time, the various parameters of the offshore wind turbines and the various parameters of the seawater, the relationship between the scour depth safety value threshold and scour rate of the offshore wind turbines and the various parameters of the seawater in different environments and states is analyzed.

[0009] S3. Stability analysis: Monitor the scouring depth of the offshore wind turbine, obtain the current environment of the offshore wind turbine and various parameters of the offshore wind turbine, judge the stability of the offshore wind turbine, if the stability is good, analyze whether maintenance warning is needed, if necessary, analyze the maintenance warning level, if the stability is poor, issue a warning.

[0010] S4. Early warning feedback: When the stability of the offshore wind turbine is poor, an early warning is issued. When a maintenance early warning is required, the maintenance early warning level of the offshore wind turbine is obtained and an early warning is issued. The staff will formulate a plan based on the early warning.

[0011] In a second aspect, the present invention provides an offshore wind turbine foundation scour depth monitoring system, comprising the following modules: a data monitoring module for monitoring the current environment of the offshore wind turbine, and monitoring various parameters of the offshore wind turbine and various parameters of seawater.

[0012] The data analysis module is used to obtain the stability of the offshore wind turbine generator set at each historical monitoring time from the database, and to produce a line graph according to the stability of the offshore wind turbine generator set at each historical monitoring time in chronological order. Based on the line graph and the environment in which the offshore wind turbine generator set was located at each historical monitoring time, the various parameters of the offshore wind turbine generator set and the various parameters of the seawater, the relationship between the scour depth safety value threshold and scour rate of the offshore wind turbine generator set and the various parameters of the seawater under different environments and conditions is analyzed.

[0013] The stability analysis module is used to monitor the scouring depth of offshore wind turbines, obtain the current environment of the offshore wind turbines and various parameters of the offshore wind turbines, and judge the stability of the offshore wind turbines. If the stability is good, it analyzes whether maintenance warning is needed. If necessary, it analyzes the maintenance warning level. If the stability is poor, a warning is issued.

[0014] The early warning feedback module is used to issue an early warning when the stability of the offshore wind turbine is poor. When a maintenance warning is required, it obtains the maintenance warning level of the offshore wind turbine and issues an early warning. The staff then formulates a plan based on the warning.

[0015] The database is used to store the stability of offshore wind turbines, the scouring depth of offshore wind turbines, the scouring depth of offshore wind turbines and various parameters of seawater during each historical monitoring, as well as the environment in which the offshore risk units are located and various parameters of the offshore wind turbines.

[0016] The beneficial effects of the present invention are: 1. The present invention provides a method and system for monitoring the scour depth of the foundation of an offshore wind turbine generator set. By analyzing the various information of the offshore wind turbine generator set and the various parameters of the seawater during each historical monitoring, the scour depth safety value threshold and the relationship between the scour rate and the various parameters of the seawater of the offshore wind turbine generator set in different environments and states are analyzed, the various information of the current offshore wind turbine generator set is monitored, and the stability of the current offshore wind turbine generator set is judged. If the stability is poor, an early warning is issued. If the stability is good, it is analyzed whether a maintenance early warning is needed. If necessary, the various parameters of the current seawater are obtained. According to the relationship between the various parameters of the current seawater and the scour rate and the various parameters of the seawater, the maintenance and other early warning levels of the offshore wind turbine generator set are judged, and an early warning is issued, thereby ensuring the effectiveness of the stability judgment of the offshore wind turbine generator set and the timeliness of the maintenance of the offshore wind turbine generator set.

[0017] 2. The present invention obtains the stability of the offshore wind turbine generator set, the scour depth of the offshore wind turbine generator set, the scour depth of the offshore wind turbine generator set, the environment in which the offshore risk generator set is located, and various parameters of the offshore wind turbine generator set at each historical monitoring from the database, analyzes the scour depth safety value threshold of the offshore wind turbine generator set in different environments and states, and monitors the various parameters of the current offshore wind turbine generator set and the scour depth of the offshore wind turbine generator set, obtains the scour depth safety value threshold of the current offshore wind turbine generator set, and judges the stability of the offshore wind turbine generator set, thereby ensuring the effectiveness of the judgment of the stability of the offshore wind turbine generator set.

[0018] 3. The present invention obtains the various parameters of seawater and the scouring depth of offshore wind turbines at each historical monitoring from the database, analyzes the relationship between the scouring rate and the various parameters of seawater, and determines whether a maintenance warning is needed when the stability of the offshore wind turbine is good. If necessary, the current various parameters of seawater are monitored, and the maintenance warning level of the offshore wind turbine is analyzed and a warning is issued, thereby ensuring the timeliness of maintenance of the offshore wind turbine. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 The figure is a schematic flow chart of the steps for implementing the method of the present invention.

[0021] Figure 2 This is a schematic diagram of the system structure connection of the present invention. DETAILED DESCRIPTION

[0022] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0023] See also Figure 1 As shown, the present invention provides a method for monitoring the scour depth of an offshore wind turbine foundation, comprising: S1, data monitoring: monitoring the current environment of the offshore wind turbine, and monitoring various parameters of the offshore wind turbine and various parameters of seawater.

[0024] It should be noted that the present method and system are connected to a meteorological system, and the current environment of the offshore wind turbine is obtained from the meteorological system.

[0025] It should also be noted that the parameters of offshore wind turbines include structural strain value, modal frequency and tilt angle, and the parameters of seawater include temperature, pH value, sand content and flow rate. The parameters of offshore wind turbines are collected through instruments such as tower bottom strain gauges, accelerometers and pile foundation inclinometers, and the parameters of seawater are collected through instruments such as temperature sensors, pH sensors, sand content sensors and flow rate sensors.

[0026] S2. Data analysis: The stability of the offshore wind turbines at each historical monitoring time is obtained from the database, and a line graph is made according to the stability of the offshore wind turbines at each historical monitoring time in chronological order. Based on the line graph and the environment in which the offshore wind turbines are located at each historical monitoring time, the various parameters of the offshore wind turbines and the various parameters of the seawater, the relationship between the scour depth safety value threshold and scour rate of the offshore wind turbines and the various parameters of the seawater in different environments and states is analyzed.

[0027] In a specific embodiment, the data analysis process is as follows: the stability of the offshore wind turbine at each historical monitoring time is obtained from the database, the monitoring time is used as the x-axis, and the stability of the offshore wind turbine is used as the y-axis, a line graph is established, and the line segments of the line graph are obtained according to the inflection points in the line graph, and the slope of each line segment is obtained. The line segments with a slope less than zero are called marked line segments, and the time periods corresponding to the marked line segments are called marked time periods.

[0028] It should be noted that, each inflection point in the line graph is obtained, and the line segment between adjacent inflection points is divided into one line segment, so as to obtain each line segment in the line graph in this way.

[0029] The environment of the offshore risk unit and the various parameters of the offshore wind turbine in each marked time period are obtained from the database, and the scouring depth safety value threshold of the offshore wind turbine in different environments and conditions is analyzed. At the same time, the scouring depth of the offshore wind turbine and the various parameters of seawater at each historical monitoring time are obtained from the database, and the relationship between the scouring rate and the various parameters of seawater is analyzed.

[0030] It should be noted that the various parameters of offshore wind turbines are related to the stiffness, stress and stability of offshore wind turbines. The change in the structural strain value directly reflects the stress state of the foundation structure. The modal frequency is the core indicator reflecting the structural stiffness, and the inclination angle is an intuitive indicator reflecting the overall stability of the foundation.

[0031] It should also be noted that flow velocity is the most direct factor determining the intensity of scouring, and it is significantly positively correlated with the scouring rate. The sediment content indirectly regulates the scouring rate by affecting the erosion and transportation process of sediment. Temperature mainly affects the dynamic characteristics of water flow by changing the density and viscosity of seawater, thereby affecting the scouring rate. The pH value mainly affects the dissolution of sediment through chemical effects, thereby affecting the scouring rate.

[0032] In the above, the analysis of the scour depth safety value threshold of offshore wind turbines in different environments and states is carried out as follows: the marked time periods in which the offshore risk units are in the same environment and the parameters of the offshore wind turbines are the same are divided into an analysis group, and each analysis group is obtained by this method. Based on the stability of the offshore wind turbines during each historical monitoring in each marked time period in each analysis group, the historical secondary marked monitoring of each analysis group is obtained.

[0033] It should be noted that in an analysis group, the offshore risk units in each marked time period in the analysis group are in the same environment and the status of the offshore wind turbines is the same. If the parameter values ​​of the offshore wind turbines in two marked time periods are the same, it means that the status of the offshore wind turbines in the two marked time periods is the same.

[0034] The scour depths of offshore wind turbines during each historical secondary mark monitoring of each analysis group are obtained from the database and compared to obtain the minimum scour depth of each analysis group. This is used as the scour depth safety value threshold of the offshore wind turbine in the corresponding environment and state of each analysis group. This method is used to analyze the scour depth safety value threshold of the offshore wind turbine in different environments and states.

[0035] In the above, the specific process of obtaining the historical secondary mark monitoring of each analysis group is as follows: in each analysis group, the stability of the offshore wind turbine during each historical monitoring in each marked time period is obtained, and the historical monitoring of poor stability of the offshore wind turbine in each marked time period is called each historical mark monitoring, and the monitoring time of each historical mark monitoring in each marked time period is compared, and the historical mark monitoring with the earliest monitoring time in each marked time period is called each historical secondary mark monitoring. In this way, the historical secondary mark monitoring of each analysis group is obtained.

[0036] In the above, the relationship between the scouring rate and the various parameters of seawater is analyzed, and the specific process is as follows: the values ​​of the various parameters of seawater at each historical monitoring are compared, and the historical monitoring times with the same values ​​of the various parameters of seawater are clustered to obtain each monitoring time period, and the scouring depth of the offshore wind turbine at each historical monitoring time period in each monitoring time period is obtained from the database, and the scouring rate in each monitoring time period is calculated.

[0037] The parameters of seawater in each monitoring time period and the flushing rate in each monitoring time period are input into the LSTM network to obtain the relationship between the flushing rate and the parameters of seawater.

[0038] It should be noted that the "input sequence-output label" sample is constructed by the sliding window method. The input sequence is the various parameters of seawater in each monitoring time period, and the output label is the flushing rate of each monitoring time period. The input layer of the LSTM network receives the various parameters of seawater in each monitoring time period. The first layer of LSTM is set with 64 neurons, which retains the flushing rate of each monitoring time period to capture the impact of short-term parameter changes on the flushing rate. The second layer of LSTM is set with 32 neurons, which only retains the flushing rate of the last monitoring time period to integrate the cumulative impact of long-term parameter trends on flushing, and outputs the predicted flushing rate through the fully connected layer.

[0039] S3. Stability analysis: Monitor the scouring depth of the offshore wind turbine, obtain the current environment of the offshore wind turbine and various parameters of the offshore wind turbine, judge the stability of the offshore wind turbine, if the stability is good, analyze whether maintenance warning is needed, if necessary, analyze the maintenance warning level, if the stability is poor, issue a warning.

[0040] It should be noted that the scouring depth of the offshore wind turbines is obtained by performing high-precision scanning of the terrain surrounding the offshore wind turbines using a dual-axis rotating sonar.

[0041] In a specific embodiment, the stability analysis is specifically carried out as follows: according to the scour depth safety value thresholds of the offshore wind turbine in different environments and states, an environment-state-scour depth safety value threshold table is constructed, the current environment of the offshore risk unit and the parameter values ​​of the offshore wind turbine are obtained, and according to the environment-state-scour depth safety value threshold table, the current scour depth safety value threshold is obtained, and the current scour depth of the offshore wind turbine is monitored to judge the stability of the offshore wind turbine. If the stability of the offshore wind turbine is good, it is judged whether a maintenance warning is needed. If a maintenance warning is needed, the current scour rate is obtained, and the maintenance warning level of the offshore wind turbine is analyzed according to the current scour rate and the current scour depth of the offshore wind turbine. If the stability of the offshore wind turbine is poor, a warning is issued.

[0042] It should be noted that the environment-state-scour depth safety value threshold table includes the environment in which the offshore wind turbine is located, the various parameter values ​​of the offshore wind turbine, and the scour depth safety value threshold. The current scour depth safety value threshold can be determined based on the current environment in which the offshore wind turbine is located and the various parameter values ​​of the current offshore wind turbine.

[0043] In the above, the specific process of judging the stability of the offshore wind turbine is as follows: comparing the current scour depth of the offshore wind turbine with the current scour depth safety value threshold. If the current scour depth of the offshore wind turbine is less than the current scour depth safety value threshold, it means that the stability of the offshore wind turbine is good. If the current scour depth of the offshore wind turbine is greater than the current scour depth safety value threshold, it means that the stability of the offshore wind turbine is poor.

[0044] In the above, the specific process of judging whether a maintenance warning is needed is as follows: obtaining the current scour depth of the offshore wind turbine and comparing it with the preset scour depth threshold. If the current scour depth of the offshore wind turbine is less than the preset scour depth threshold, it means that no maintenance warning is required. If the current scour depth of the offshore wind turbine is greater than the preset scour depth threshold, it means that a maintenance warning is required.

[0045] It should be noted that the preset scour depth threshold is a critical value used to determine whether an offshore wind turbine requires maintenance warning. The current scour depth safety value threshold is obtained, and three-fifths of the current scour depth safety value threshold is used as the preset scour depth threshold.

[0046] In the above, the specific process of analyzing the maintenance warning level of the offshore wind turbine is as follows: obtaining the current scour depth safety value threshold, and based on the current scour rate, the current scour depth of the offshore wind turbine and the current scour depth safety value threshold, calculating the time required for the scour depth of the offshore wind turbine to reach the current scour depth safety value threshold, and comparing it with the preset first time threshold and the preset second time threshold. If the time required for the scour depth of the offshore wind turbine to reach the current scour depth safety value threshold is less than the preset second time threshold, the maintenance warning level of the offshore wind turbine is a first-level warning. If the time required for the scour depth of the offshore wind turbine to reach the current scour depth safety value threshold is greater than the preset second time threshold and less than the preset first time threshold, the maintenance warning level of the offshore wind turbine is a second-level warning. If the time required for the scour depth of the offshore wind turbine to reach the current scour depth safety value threshold is greater than the preset first time threshold, the maintenance warning level of the offshore wind turbine is a third-level warning.

[0047] It should be noted that the preset first time threshold and the preset second time threshold are critical values ​​for analyzing the maintenance level of offshore wind turbines and are set by relevant staff.

[0048] It should also be noted that the lower the maintenance warning level, the shorter the time required for the scour depth of the offshore wind turbine to reach the current scour depth safety value threshold, and the higher the maintenance priority.

[0049] S4. Early warning feedback: When the stability of the offshore wind turbine is poor, an early warning is issued. When a maintenance early warning is required, the maintenance early warning level of the offshore wind turbine is obtained and an early warning is issued. The staff will formulate a plan based on the early warning.

[0050] It should be noted that when a warning is issued due to poor stability, the warning is issued through an alarm; when it is a maintenance warning, the warning is issued through voice, and the maintenance warning level of the offshore wind turbine is broadcast at the same time.

[0051] See also Figure 2 As shown, the present invention provides an offshore wind turbine foundation scour depth monitoring system, including: a data monitoring module for monitoring the current environment of the offshore wind turbine and monitoring various parameters of the offshore wind turbine and various parameters of seawater.

[0052] The data analysis module is used to obtain the stability of the offshore wind turbine generator set at each historical monitoring time from the database, and to produce a line graph according to the stability of the offshore wind turbine generator set at each historical monitoring time in chronological order. Based on the line graph and the environment in which the offshore wind turbine generator set was located at each historical monitoring time, the various parameters of the offshore wind turbine generator set and the various parameters of the seawater, the relationship between the scour depth safety value threshold and scour rate of the offshore wind turbine generator set and the various parameters of the seawater under different environments and conditions is analyzed.

[0053] The stability analysis module is used to monitor the scouring depth of offshore wind turbines, obtain the current environment of the offshore wind turbines and various parameters of the offshore wind turbines, and judge the stability of the offshore wind turbines. If the stability is good, it analyzes whether maintenance warning is needed. If necessary, it analyzes the maintenance warning level. If the stability is poor, a warning is issued.

[0054] The early warning feedback module is used to issue an early warning when the stability of the offshore wind turbine is poor. When a maintenance warning is required, it obtains the maintenance warning level of the offshore wind turbine and issues an early warning. The staff then formulates a plan based on the warning.

[0055] The database is used to store the stability of offshore wind turbines, the scouring depth of offshore wind turbines, the scouring depth of offshore wind turbines and various parameters of seawater during each historical monitoring, as well as the environment in which the offshore risk units are located and various parameters of the offshore wind turbines.

[0056] The embodiment of the present invention analyzes the relationship between the scouring depth safety value threshold and the scouring rate of the offshore wind turbine in different environments and states and the various parameters of the seawater through various information of the offshore wind turbine at each historical monitoring and various parameters of the seawater, monitors various information of the current offshore wind turbine, and judges the stability of the current offshore wind turbine. If the stability is poor, an early warning is issued. If the stability is good, it is analyzed whether a maintenance early warning is needed. If necessary, the various parameters of the current seawater are obtained. According to the relationship between the various parameters of the current seawater and the scouring rate and the various parameters of the seawater, the maintenance and other early warning levels of the offshore wind turbine are judged, and an early warning is issued, thereby ensuring the effectiveness of the stability judgment of the offshore wind turbine and the timeliness of the maintenance of the offshore wind turbine.

[0057] The above content is merely an example and explanation of the concept of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined in this specification, they should all fall within the scope of protection of the present invention.

Claims

1. A method for monitoring the scour depth of an offshore wind turbine foundation, characterized in that: The steps include: S1. Data monitoring: monitoring the current environment of the offshore wind turbines, and monitoring various parameters of the offshore wind turbines and seawater; S2. Data Analysis: Obtain the stability of the offshore wind turbines at each historical monitoring time from the database, and create a line graph based on the stability of the offshore wind turbines at each historical monitoring time in chronological order. Based on the line graph and the environment in which the offshore wind turbines are located, various parameters of the offshore wind turbines, and various parameters of the seawater at each historical monitoring time, analyze the relationship between the scour depth safety value threshold and scour rate of the offshore wind turbines in different environments and conditions and various parameters of the seawater; S3. Stability Analysis: Monitor the scour depth of the offshore wind turbine and obtain the current environment and parameters of the offshore wind turbine to determine the stability of the offshore wind turbine. If the stability is good, analyze whether maintenance warning is needed. If so, analyze the maintenance warning level. If the stability is poor, issue a warning. S4. Early warning feedback: When the stability of the offshore wind turbine is poor, an early warning is issued. When a maintenance early warning is required, the maintenance early warning level of the offshore wind turbine is obtained and an early warning is issued. The staff will formulate a plan based on the early warning.

2. The method for monitoring the scour depth of an offshore wind turbine foundation according to claim 1, characterized in that: The specific process of data analysis is as follows: Obtain the stability of the offshore wind turbine at each historical monitoring time from the database, establish a broken line graph with the monitoring time as the x-axis and the stability of the offshore wind turbine as the y-axis, and obtain each line segment of the broken line graph according to the inflection point in the broken line graph, obtain the slope of each line segment, and refer to each line segment with a slope less than zero as a marked line segment, and each time period corresponding to each marked line segment as a marked time period; The environment of the offshore risk unit and the various parameters of the offshore wind turbine in each marked time period are obtained from the database, and the scouring depth safety value threshold of the offshore wind turbine in different environments and conditions is analyzed. At the same time, the scouring depth of the offshore wind turbine and the various parameters of seawater at each historical monitoring time are obtained from the database, and the relationship between the scouring rate and the various parameters of seawater is analyzed.

3. The method for monitoring the scour depth of an offshore wind turbine foundation according to claim 2, characterized in that: The specific process of analyzing the scour depth safety threshold of offshore wind turbines in different environments and conditions is as follows: The offshore risk units with the same environment and the same parameters of the offshore wind turbines are divided into an analysis group. In this way, each analysis group is obtained. Based on the stability of the offshore wind turbines during each historical monitoring in each marked time period in each analysis group, each historical secondary marked monitoring of each analysis group is obtained. The scour depths of offshore wind turbines during each historical secondary mark monitoring of each analysis group are obtained from the database and compared to obtain the minimum scour depth of each analysis group. This is used as the scour depth safety value threshold of the offshore wind turbine in the corresponding environment and state of each analysis group. This method is used to analyze the scour depth safety value threshold of the offshore wind turbine in different environments and states.

4. The method for monitoring the scour depth of an offshore wind turbine foundation according to claim 3, characterized in that: The specific process of obtaining each historical secondary marker monitoring of each analysis group is as follows: In each analysis group, the stability of the offshore wind turbine generator set at each historical monitoring within each marked time period is obtained, and the historical monitoring times with poor stability of the offshore wind turbine generator set within each marked time period are called historical marked monitorings. The monitoring times of the historical marked monitorings within each marked time period are compared, and the historical marked monitorings with the earliest monitoring time within each marked time period are called historical secondary marked monitorings. In this way, the historical secondary marked monitorings of each analysis group are obtained.

5. The method for monitoring the scour depth of an offshore wind turbine foundation according to claim 2, characterized in that: The specific process of analyzing the relationship between the flushing rate and various parameters of seawater is as follows: The values ​​of various parameters of seawater at each historical monitoring time are compared, and the historical monitoring times with the same values ​​of various parameters of seawater are clustered to obtain each monitoring time period. The scouring depth of the offshore wind turbine at each historical monitoring time period in each monitoring time period is obtained from the database, and the scouring rate in each monitoring time period is calculated; The parameters of seawater in each monitoring time period and the flushing rate in each monitoring time period are input into the LSTM network to obtain the relationship between the flushing rate and the parameters of seawater.

6. The method for monitoring the scour depth of an offshore wind turbine foundation according to claim 1, characterized in that: The specific process of the stability analysis is as follows: According to the scour depth safety value thresholds of offshore wind turbines in different environments and states, an environment-state-scour depth safety value threshold table is constructed to obtain the current environment of the offshore risk unit and the parameter values ​​of the offshore wind turbine. According to the environment-state-scour depth safety value threshold table, the current scour depth safety value threshold is obtained, and the current scour depth of the offshore wind turbine is monitored to judge the stability of the offshore wind turbine. If the stability of the offshore wind turbine is good, it is judged whether a maintenance warning is needed. If a maintenance warning is needed, the current scour rate is obtained. According to the current scour rate and the current scour depth of the offshore wind turbine, the maintenance warning level of the offshore wind turbine is analyzed. If the stability of the offshore wind turbine is poor, a warning is issued.

7. The method for monitoring the scour depth of an offshore wind turbine foundation according to claim 6, characterized in that: The specific process of judging the stability of offshore wind turbines is as follows: The current scour depth of the offshore wind turbine is compared with the current scour depth safety value threshold. If the current scour depth of the offshore wind turbine is less than the current scour depth safety value threshold, it means that the stability of the offshore wind turbine is good. If the current scour depth of the offshore wind turbine is greater than the current scour depth safety value threshold, it means that the stability of the offshore wind turbine is poor.

8. The method for monitoring the scour depth of an offshore wind turbine foundation according to claim 6, characterized in that: The specific process of determining whether a maintenance warning is required is as follows: Obtain the current scour depth of the offshore wind turbine and compare it with the preset scour depth threshold. If the current scour depth of the offshore wind turbine is less than the preset scour depth threshold, it means that no maintenance warning is required. If the current scour depth of the offshore wind turbine is greater than the preset scour depth threshold, it means that a maintenance warning is required.

9. The method for monitoring the scour depth of an offshore wind turbine foundation according to claim 6, characterized in that: The specific process of analyzing the maintenance warning level of offshore wind turbines is as follows: Obtain the current scour depth safety value threshold, and based on the current scour rate, the current scour depth of the offshore wind turbine and the current scour depth safety value threshold, calculate the time required for the scour depth of the offshore wind turbine to reach the current scour depth safety value threshold, and compare it with the preset first time threshold and the preset second time threshold. If the time required for the scour depth of the offshore wind turbine to reach the current scour depth safety value threshold is less than the preset second time threshold, the maintenance warning level of the offshore wind turbine is a first-level warning. If the time required for the scour depth of the offshore wind turbine to reach the current scour depth safety value threshold is greater than the preset second time threshold and less than the preset first time threshold, the maintenance warning level of the offshore wind turbine is a second-level warning. If the time required for the scour depth of the offshore wind turbine to reach the current scour depth safety value threshold is greater than the preset first time threshold, the maintenance warning level of the offshore wind turbine is a third-level warning.

10. A monitoring system for executing the method for monitoring the scour depth of an offshore wind turbine foundation according to any one of claims 1 to 9, characterized in that: include: The data monitoring module is used to monitor the current environment of the offshore wind turbine and monitor various parameters of the offshore wind turbine and seawater; The data analysis module is used to obtain the stability of the offshore wind turbine generator set at each historical monitoring time from the database, and to produce a broken line graph according to the stability of the offshore wind turbine generator set at each historical monitoring time in chronological order. Based on the broken line graph and the environment in which the offshore wind turbine generator set is located at each historical monitoring time, various parameters of the offshore wind turbine generator set, and various parameters of the seawater, the relationship between the scour depth safety value threshold and scour rate of the offshore wind turbine generator set and various parameters of the seawater under different environments and conditions is analyzed; The stability analysis module is used to monitor the scouring depth of offshore wind turbines, obtain the current environment of the offshore wind turbines and various parameters of the offshore wind turbines, and judge the stability of the offshore wind turbines. If the stability is good, it analyzes whether maintenance warning is needed. If so, it analyzes the maintenance warning level. If the stability is poor, it will issue a warning. The early warning feedback module is used to issue an early warning when the stability of the offshore wind turbine is poor. When a maintenance warning is required, it obtains the maintenance warning level of the offshore wind turbine and issues an early warning. The staff then formulates a plan based on the warning. The database is used to store the stability of offshore wind turbines, the scouring depth of offshore wind turbines, the scouring depth of offshore wind turbines and various parameters of seawater during each historical monitoring, as well as the environment in which the offshore risk units are located and various parameters of the offshore wind turbines.

Images