Cable laying out rate adjusting method and device, electronic equipment and storage medium

Abstract

The application provides a submarine cable laying out-cable speed adjustment method and device, electronic equipment and a storage medium, and relates to the technical field of submarine cable laying. The method obtains a current sea current flow rate value and a current overhang section length, then calculates an initial natural frequency offset, determines the lock interval boundary of vortex-induced vibration, marks the component falling within the lock interval boundary in the real-time vibration frequency as a vortex-induced vibration interference feature, performs band-stop filtering on the original tension signal of the overhang section by using the feature, outputs a purified tension reading sequence, extracts a static tension identification component from the purified tension reading sequence, compares the static tension identification component with a preset target tension interval, calculates a speed adjustment demand vector according to the deviation direction and deviation amplitude obtained by comparison, and calculates a speed output value according to the current out-cable speed and the speed adjustment demand vector. Thus, the resonance risk caused by vortex-induced vibration is effectively avoided, and the safety of submarine cable laying is ensured.

Description

Technical Field

[0001] This invention relates to the field of submarine cable laying technology, and in particular to a method, device, electronic equipment, and storage medium for adjusting the cable delivery rate during submarine cable laying. Background Technology

[0002] In marine engineering, submarine cable laying operations often face interference from vortex-induced vibration. Vortex-induced vibration refers to the periodic vibration caused by ocean currents acting on the suspended section of the submarine cable. This vibration is directly superimposed on the tension monitoring signal, forming an inaccurate wave component that masks the true static stress state of the submarine cable.

[0003] Existing methods typically suppress vibration by adjusting the cable delivery rate. However, because they cannot accurately separate the actual tension from the aliased signal, the rate adjustment decisions become inaccurate, increasing the risk of cable overload and breakage or bottoming out. Therefore, effectively identifying and filtering out the interference of eddy-induced vibration on the tension signal is crucial for the safe deployment of submarine cables. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method, device, electronic equipment and storage medium for adjusting the cable delivery rate of submarine cable laying, which can achieve stable tension sensing and adaptive and precise control of the laying rate while suppressing vortex-induced vibration interference, so as to ensure the safety of submarine cable laying operations.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A method for adjusting the cable delivery rate during submarine cable deployment includes: Obtain the current ocean current velocity and the current length of the suspended section of the submarine cable, calculate the initial natural frequency offset, and determine the locking interval boundary of the vortex-induced vibration. Extract the natural frequency features of each order from the spectrum of the real-time vibration frequency of the suspension section, and calculate the frequency offset of each natural frequency feature relative to the boundary of the locking interval. If any of the frequency offsets exceeds a preset offset threshold, the locking interval boundary is dynamically adjusted according to the change in the length of the overhang segment. The components of the real-time vibration frequency that fall within the boundary of the locked interval are marked as vortex-induced vibration interference features. The original tension signal of the suspension section is band-stop filtered using the vortex-induced vibration interference features to output a purified tension reading sequence. The static tension identification component is extracted from the purified tension reading sequence and compared with the preset target tension range. Based on the deviation direction and deviation magnitude obtained from the comparison, the rate adjustment demand vector is calculated. Based on the current cable delivery rate and the rate adjustment demand vector, the rate output value is calculated, and the cable delivery rate of the submarine cable is adjusted accordingly.

[0006] To solve the above-mentioned technical problems, another technical solution adopted by the present invention is as follows: A cable delivery rate adjustment device for submarine cable laying includes: The locking interval boundary determination unit is used to obtain the current ocean current velocity value and the current suspension section length of the submarine cable, calculate the initial natural frequency offset, and determine the locking interval boundary of vortex-induced vibration. The frequency offset determination unit is used to extract the natural frequency features of each order from the spectrum of the real-time vibration frequency of the suspension section, and calculate the frequency offset of each natural frequency feature relative to the boundary of the locking interval. A locking interval boundary adjustment unit is used to dynamically adjust the locking interval boundary according to the change in the length of the suspended segment if any of the frequency offsets exceeds a preset offset threshold. The tension adjustment unit is used to mark the components of the real-time vibration frequency that fall within the boundary of the locking interval as vortex-induced vibration interference features, and to use the vortex-induced vibration interference features to perform band-stop filtering on the original tension signal of the suspension section, and output the purified tension reading sequence. The rate adjustment calculation unit is used to extract the static tension identification component from the purified tension reading sequence, compare it with the preset target tension range, and calculate the rate adjustment demand vector based on the deviation direction and deviation magnitude obtained from the comparison. The cable delivery rate calculation unit is used to calculate the rate output value based on the current cable delivery rate and the rate adjustment demand vector, thereby adjusting the cable delivery rate of the submarine cable.

[0007] To solve the above-mentioned technical problems, another technical solution adopted by the present invention is as follows: An electronic device includes a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor executes the computer program to implement the method described above.

[0008] To solve the above-mentioned technical problems, another technical solution adopted by the present invention is as follows: A storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described above.

[0009] The beneficial effects of this invention are as follows: by collecting ocean current velocity and suspended section length, calculating the initial natural frequency offset, and monitoring the vibration frequency in real time, the boundary of the vortex-induced vibration locking interval is dynamically adjusted to identify and filter out non-real tension components, thereby obtaining the tension reading of the suspended section after purification. The static tension identification component is extracted from the purified tension reading sequence and compared with the preset target tension range. Based on the comparison, the rate adjustment demand vector is calculated, and then the rate output value is calculated to adjust the cable delivery rate of the submarine cable. Thus, while suppressing vortex-induced vibration interference, stable tension sensing and adaptive and precise control of the laying rate are achieved, ensuring the safety of submarine cable laying operations. Attached Figure Description

[0010] Figure 1 This is a flowchart of a method for adjusting the cable delivery rate during submarine cable laying, according to an embodiment of the present invention. Figure 2 A flowchart illustrating step 110 provided in an embodiment of the present invention; Figure 3 A flowchart illustrating step 120 provided in an embodiment of the present invention; Figure 4 A flowchart illustrating step 130 provided in an embodiment of the present invention; Figure 5 A flowchart illustrating step 140 provided in an embodiment of the present invention; Figure 6 A flowchart illustrating step 150 provided in an embodiment of the present invention; Figure 7 A flowchart illustrating step 160 provided in an embodiment of the present invention; Figure 8 This is a schematic diagram of a cable delivery rate adjustment device for submarine cable laying according to an embodiment of the present invention. Figure 9 This is a schematic diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0011] Definitions:

[0012] To explain in detail the technical content, objectives, and effects of the present invention, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0013] In existing technologies, submarine cable laying is a crucial process in marine engineering, widely used in submarine power transmission, optical cable laying, and offshore oil and gas pipeline installation. Laying operations are typically conducted at sea by specialized cable-laying vessels. The appropriate tension in the suspended section of the cable is maintained by controlling the cable delivery rate, ensuring a smooth landing on the seabed. However, ocean currents, prevalent in the marine environment, cause periodic currents around the suspended section of the cable, inducing vortex-induced vibration. This vibration signal is directly superimposed on the monitoring readings of the tension sensor, forming a wave component unrelated to the actual static force. This makes it impossible for operators or automatic control systems to accurately determine the actual stress state of the cable. Existing methods for adjusting the cable delivery rate usually rely on direct observation of the original tension signal, failing to effectively distinguish between the actual tension component and the vortex-induced vibration interference component. This results in rate adjustment decisions based on distorted signals, easily leading to cable bottoming and accumulation due to excessively fast delivery or cable breakage due to excessively slow delivery, severely restricting the safety and reliability of submarine cable laying operations.

[0014] To at least address the aforementioned issues, this invention determines the locked frequency range of vortex-induced vibration and utilizes the interference characteristics of vortex-induced vibration to perform band-stop filtering on the tension signal of the suspended section of the submarine cable. This separates the purified true static tension from the aliased signal. Then, based on the deviation of the purified tension from the target tension range, the rate adjustment demand vector is calculated, ultimately outputting the stabilized cable delivery rate value. In this way, the contamination of the tension monitoring signal by vortex-induced vibration can be accurately removed in environments with ocean current interference, obtaining a true static tension reading. This ensures that the cable delivery rate adjustment decision is always based on reliable tension information, effectively avoiding misoperation caused by signal aliasing and improving the safety and automated control accuracy of submarine cable laying operations.

[0015] The following describes in detail a method for adjusting the cable delivery rate during submarine cable laying according to the present invention. Please refer to [link / reference]. Figure 1 The method includes steps 110 to 160: Step 110: Obtain the current ocean current velocity and the current suspension length of the submarine cable, calculate the initial natural frequency offset, and determine the locking interval boundary of vortex-induced vibration.

[0016] Step 120: Extract the natural frequency features of each order from the spectrum of the real-time vibration frequency of the suspension section, and calculate the frequency offset of each natural frequency feature relative to the boundary of the locking interval.

[0017] Step 130: If any of the frequency offsets exceeds a preset offset threshold, the locking interval boundary is dynamically adjusted according to the change in the length of the suspended segment.

[0018] Step 140: The components of the real-time vibration frequency that fall within the boundary of the locked interval are marked as vortex-induced vibration interference features. The original tension signal of the suspended section is band-stop filtered using the vortex-induced vibration interference features to output the purified tension reading sequence.

[0019] Step 150: Extract the static tension identification component from the purified tension reading sequence, compare it with the preset target tension range, and calculate the rate adjustment demand vector based on the deviation direction and deviation magnitude obtained from the comparison.

[0020] Step 160: Calculate the rate output value based on the current cable delivery rate and the rate adjustment demand vector, and adjust the cable delivery rate of the submarine cable accordingly.

[0021] This method extracts the spectral characteristics of the real-time vibration frequency of the suspended section and compares them with the boundary of the dynamically locked interval to accurately mark the vortex-induced vibration interference components. It then uses band-stop filtering to remove spurious components from the original tension signal, obtaining the purified true static tension. Based on this, closed-loop rate adjustment is performed, thereby effectively suppressing the impact of vibration interference on tension monitoring, achieving accurate control of the cable delivery rate, and improving the safety and reliability of submarine cable laying operations.

[0022] Steps 110 to 160 above are executed periodically at preset time intervals (e.g., 2 seconds, 5 seconds, 10 seconds, etc.). Within each cycle, the current ocean current velocity, suspended section length data, real-time vibration frequency, and original tension signal are reacquired, and the locking interval boundary, filtering benchmark, and rate output value are dynamically updated. Through this periodic execution, the embodiments of the present invention can adapt in real time to rapid changes in ocean current velocity under complex sea conditions and continuous changes in suspended section length due to adjustments in cable delivery rate, ensuring that the identification and filtering of vortex-induced vibration interference are always based on the latest operating conditions, maintaining the accuracy and stability of cable delivery rate control.

[0023] First, step 110 is executed. The current velocity value of the current sea area is acquired in real time by a current velocity acquisition unit deployed at the submarine cable laying site. Simultaneously, the actual length data of the current suspension section is acquired by a suspension section length monitoring device. Based on the current velocity value and suspension section length data, combined with the submarine cable structural parameters and fluid dynamics principles, the initial natural frequency offset of the suspension section under the current operating conditions is calculated. Using this initial natural frequency offset as a correction basis, the boundary of the locked interval characterizing the frequency band prone to vortex-induced vibration is dynamically determined. This locked interval boundary is a continuous frequency range, and its upper and lower limits jointly define the critical frequency region where vortex-induced vibration may be excited.

[0024] The ocean current velocity acquisition unit uses a Doppler current meter or an acoustic current meter, which is deployed on the side of the cable laying vessel or near the water entry point of the suspended section to collect the ocean current velocity value in real time.

[0025] Optionally, to reduce measurement errors in ocean current velocity, a calibration coefficient is read according to the measurement range of the ocean current velocity, and the ocean current velocity is multiplied by the calibration coefficient to obtain the calibrated velocity data. The measurement range of the ocean current velocity value is pre-divided based on historical velocity data of the operating sea area. Each measurement range corresponds to a velocity calibration coefficient, which is obtained through on-site calibration to eliminate measurement deviations caused by instrument drift and environmental factors.

[0026] The suspension length monitoring device may include an encoder or laser rangefinder installed at the cable exit point, which records the length of the cable segment from the cable leaving the deployment vessel to the entry point into the water and outputs the suspension length.

[0027] In one alternative implementation, see [link to implementation details]. Figure 2 Step 110 may include the following sub-steps: Step 111: Calculate the vortex shedding frequency based on the Strolla number formula, according to the current ocean current velocity and the cable diameter.

[0028] Step 112: Perform a difference calculation between the vortex shedding frequency and the preset natural vibration fundamental frequency of the suspension section to obtain the initial natural frequency offset.

[0029] Step 113: Determine the excitation frequency range of vortex-induced vibration based on the vortex shedding frequency.

[0030] Step 114: Superimpose the excitation frequency range with the initial natural frequency offset to obtain the locking interval boundary of vortex-induced vibration.

[0031] Specifically, the length L of the suspended section is read from the suspension section length monitoring device. Based on the ocean current velocity and L, the vortex shedding frequency f is calculated according to the relationship that the vortex shedding frequency f is directly proportional to the current velocity and inversely proportional to the characteristic length, f = St × vc / d, where St is the Strocha number and d is the cable diameter. The difference between f and the preset natural vibration fundamental frequency f0 of the suspended section is calculated to obtain the initial natural frequency offset Δf = f - f0. The preset natural vibration fundamental frequency of the suspended section is pre-determined and stored in the electronic equipment based on the material properties, diameter, and length of the cable.

[0032] The theoretical excitation frequency range of vortex-induced vibration is determined based on the vortex shedding frequency (e.g., the lower limit is 0.8 times the vortex shedding frequency, and the upper limit is 1.2 times the vortex shedding frequency). Then, this entire excitation frequency range is superimposed with the initial natural frequency offset to obtain the locking interval boundary of the vortex-induced vibration (including the lower and upper boundary values). The locking interval is a specific range in the field of vortex-induced vibration describing the vibration frequency being locked by the ocean current excitation frequency. When the natural frequency of the overhang falls into this interval, the vortex shedding frequency synchronizes with the natural frequency, and the vibration amplitude increases significantly.

[0033] By determining the locked interval boundary of vortex-induced vibration through steps 111 to 114, the vortex shedding frequency is inverted using the Strocha number formula based on the measured ocean current velocity, and the initial natural frequency offset is obtained by combining it with the natural vibration fundamental frequency of the overhang section. This offset is then superimposed on the theoretical excitation frequency range, so that the locked interval boundary is adaptively generated according to the current hydrodynamic conditions, rather than using a fixed empirical frequency band. This more accurately defines the critical frequency region where vortex-induced vibration is actually prone to occur, providing a physically interpretable and real-time condition-fitting judgment benchmark for subsequent frequency offset calculation and interference component identification.

[0034] After obtaining the boundary of the locked interval, step 120 is executed: real-time vibration signals are collected using vibration sensors deployed on the suspended section, and the frequency characteristics corresponding to each order of natural vibration of the suspended section are extracted; and the frequency offset of each order of natural frequency characteristic is calculated. This frequency offset reflects the frequency interval between the current natural frequency and the boundary of the locked interval. In an optional implementation, see [link to implementation details]. Figure 3 Step 120 may include the following sub-steps: Step 121: Perform a fast Fourier transform on the real-time vibration frequency of the suspended section to obtain the frequency domain vibration spectrum.

[0035] Step 122: Identify the peak positions in the frequency domain vibration spectrum where the amplitude exceeds a preset noise threshold, and extract the natural frequency features of each order.

[0036] Step 123: For each order of the inherent frequency feature, calculate the absolute value of the difference between the inherent frequency feature and the lower boundary value and the upper boundary value of the locked interval boundary, and take the smallest absolute value of the difference as the frequency offset corresponding to that order.

[0037] Specifically, real-time vibration signals of the suspended section are collected from vibration sensors deployed on the suspended section. A vibration spectrum analysis unit then performs a Fast Fourier Transform (FFT) on these signals, converting the time-domain vibration signal into a frequency-domain vibration spectrum. Finally, the frequency positions corresponding to the vibration peaks of each order are identified from the frequency-domain vibration spectrum to obtain the natural frequency characteristics of each order.

[0038] The vibration sensors, which can be piezoelectric accelerometers or fiber optic vibration sensors, are spaced out along the axial direction of the suspended section to collect lateral vibration signals generated by the suspended section under the action of ocean currents. The vibration signals are time-domain waveform data, containing periodic vibration components of the suspended section under vortex-induced action.

[0039] After receiving the time-domain vibration signal, the vibration spectrum analysis unit performs Fast Fourier Transform (FFT) processing to convert the time-domain waveform into a frequency-domain vibration spectrum. The FFT process discretizes the continuous vibration signal according to the sampling period, and uses a butterfly operation to map the time-domain sampling points into a frequency-domain amplitude distribution. The output frequency-domain vibration spectrum, with frequency as the horizontal axis and vibration amplitude as the vertical axis, presents the vibration intensity distribution of the suspended segment at different frequencies. From the frequency-domain vibration spectrum, peak positions where the amplitude exceeds a preset noise threshold are identified. Each peak corresponds to a first-order natural frequency, and the features of each natural frequency are extracted sequentially.

[0040] Finally, the natural frequency characteristics of each order are compared with the boundary of the locked interval one by one. The absolute value of the difference between each natural frequency characteristic and the upper and lower boundary values ​​is calculated. The smaller difference between the two is taken as the frequency offset corresponding to that order. This value reflects the frequency interval between the natural frequency and the nearest boundary of the locked interval.

[0041] The frequency offset of each natural frequency feature in the real-time vibration signal of the suspended section is calculated through steps 121 to 123. First, the frequency domain vibration spectrum is obtained by fast Fourier transform, and after filtering out stray interference with a noise threshold, the natural frequency features of each order are extracted to ensure the reliability of the extracted frequencies. Then, the smaller of the absolute values ​​of the difference between the natural frequency of that order and the upper and lower boundaries of the locked interval is taken as the frequency offset, so as to accurately represent the interval between the natural frequency of that order and the nearest boundary of the locked interval. This quantitatively reflects the degree to which each order of vibration approaches the vortex-induced vibration excitation zone, and provides an accurate and quantifiable criterion for whether to trigger the dynamic adjustment of the boundary of the locked interval.

[0042] After obtaining the frequency offsets corresponding to each order, a threshold judgment is performed on all frequency offsets obtained in step 120; when at least one frequency offset exceeds a preset offset threshold (e.g., 2 Hz), a dynamic adjustment mechanism for locking the interval boundary is triggered. In one optional implementation, see [link to implementation details]. Figure 4 Step 130 may include the following sub-steps: Step 131: Compare the current length of the suspended section with the preset reference length of the suspended section to obtain the length change.

[0043] Step 132: Based on the inverse relationship between the length of the reference suspension section and the corresponding reference natural frequency, the length change is converted into a frequency compensation value.

[0044] Step 133: The frequency compensation value is superimposed on the lower boundary value and the upper boundary value of the locked interval boundary to obtain the adjusted locked interval boundary.

[0045] Specifically, in submarine cable laying operations, the laying vessel travels along a predetermined route, and the submarine cable is continuously released by the onboard cable release device and lowered into the water along one side of the ship until it touches the seabed. The suspended section refers to the section of the submarine cable that hangs freely in the air or above the water surface from the cable release point of the laying vessel to the point of entry into the water. The reference suspended section length is the initial suspended section length recorded at the start of the submarine cable laying operation. The initial suspended section length is determined by the ship's hull height, laying angle, and initial tension state. During the laying process, the laying vessel moves forward at a certain speed. The cable release rate and the ship speed together determine the suspended section length: when the cable release rate is lower than the matching rate required for the current speed, the amount of cable released is relatively insufficient, and the suspended section is shortened due to increased tension, resulting in a corresponding shortening of the suspended section length; when the cable release rate increases, the amount of cable released increases, and the suspended section lengthens due to decreased tension.

[0046] There is an inverse relationship between the natural frequency and the length of the suspended section. This is because, as a flexible structure, the suspended section's vibration characteristics are similar to string vibration, with its natural frequency inversely proportional to its effective vibration length. When the length of the suspended section shortens, the natural frequency increases; when the length increases, the natural frequency decreases. Based on this physical relationship, the amount of length reduction is proportionally converted into a frequency increase compensation value, which reflects the change in natural frequency caused by the change in the length of the suspended section. Furthermore, the offset processing of the locking interval boundary involves simultaneously superimposing the original upper and lower boundary values ​​with the frequency increase compensation value. This processing method is based on the fact that when the natural frequency of the suspended section increases, frequency components that were not originally within the locking interval may fall into a new excitation range due to the overall upward shift in frequency. Therefore, the locking interval boundary needs to be shifted upward synchronously to accurately reflect the actual risk area of ​​enhanced vibration. The adjusted locking interval boundary covers the frequency range that vortex-induced vibration may be excited after the change in the length of the suspended section.

[0047] For example, the current length data L of the suspended section is obtained from the suspended section length monitoring device. cur , will L cur With respect to the preset reference suspension length L ref Perform the difference operation to obtain the change in length ΔL, ΔL = L cur L ref Based on the assumption of small deformation, the natural frequency f of the suspended section is approximately inversely proportional to its length L, i.e., f = k / L, where k is a constant. Therefore, the length change is converted into a frequency compensation value Δf, calculated using the formula Δf = (f... ref / L ref )*ΔL, where f refΔL represents the natural frequency corresponding to the reference length. When ΔL is negative (i.e., the length is shortened), Δf is positive, indicating frequency increase compensation; when ΔL is positive (i.e., the length is extended), Δf is negative, indicating frequency decrease compensation. If multiple frequency offsets exceed a preset offset threshold, the Δf corresponding to the frequency offset with the largest absolute value is taken as the locking interval boundary offset to cover the most severe vibration enhancement risk. The locking interval boundary is offset based on the calculated Δf, and the upper and lower boundary values ​​are superimposed with Δf to obtain the adjusted locking interval boundary.

[0048] When at least one frequency offset exceeds a preset offset threshold, the locking interval boundary is dynamically adjusted through steps 131 to 133. The frequency compensation value is calculated based on the change in the current suspension section length relative to the reference length, according to the physical relationship that the natural frequency is inversely proportional to the suspension section length. This value is then synchronously superimposed on the upper and lower boundaries of the locking interval, enabling the locking interval to track the drift of the natural frequency in real time as the suspension section length changes. This avoids the problem of missing the actual excitation component or mistakenly including non-excitation components due to the overall frequency shift after the suspension section length changes. Thus, under the condition that the suspension section length continuously changes during the cable delivery process, the actual risk frequency band of vortex-induced vibration is continuously and accurately locked, improving the accuracy of interference identification and filtering.

[0049] During real-time tension monitoring of the suspended section in submarine cable laying operations, the suspended section is prone to vortex-induced vibration due to ocean current impact. This vibration is transmitted to the tension sensor through the submarine cable, forming an interference signal. This interference manifests as transient tension changes caused by ocean current load fluctuations, superimposed on the steady-state stress state of the submarine cable, resulting in periodic tension fluctuations in the monitoring data. Therefore, after obtaining the locking interval boundary (the adjusted locking interval boundary; if not adjusted, it is the unadjusted locking interval boundary), the original tension signal of the suspended section is processed. In one optional implementation method, see [link to implementation details]. Figure 5 Step 140 may include the following sub-steps: Step 141: Compare each frequency component of the real-time vibration frequency with the boundary of the locking interval, and mark the frequency component that falls into the boundary of the locking interval as the vortex-induced vibration interference component.

[0050] Step 142: Construct non-real tension component characteristics based on the frequency position and amplitude of each vortex-induced vibration interference component.

[0051] Step 143: Compare the frequency components of the acquired original tension signal of the suspended section with the frequency positions in the non-real tension component features.

[0052] Step 144: If the original tension signal contains a component with the same frequency position as or within the tolerance range of the non-real tension component feature, then a filter reference update signal with the frequency position of the non-real tension component feature as the stopband center is generated.

[0053] Step 145: Perform band-stop filtering on the original tension signal according to the filter reference update signal, and output the purified tension reading sequence.

[0054] Specifically, the real-time vibration frequency of the suspended section is compared frequency by frequency using the boundary of the locked interval. Each frequency component is extracted from the frequency domain vibration spectrum of the real-time vibration frequency of the suspended section. Each frequency component is numerically compared with the upper and lower boundary values ​​of the locked interval. If the frequency component falls within the range defined by the upper and lower boundary values, the frequency component is marked as a vortex-induced vibration interference component.

[0055] Based on the frequency position and amplitude of each vortex-induced vibration interference component, the frequency domain distribution characteristics of each interference component are integrated to construct the non-real tension component characteristics. These non-real tension component characteristics include the distribution position of each interference component in the frequency domain and the corresponding vibration amplitude.

[0056] The original tension signal of the suspended section is obtained from the tension sensor. A frequency domain transformation is performed on the original tension signal to extract its frequency components. Each frequency component of the original tension signal is compared one by one with the interference frequency positions recorded in the non-true tension component characteristics. If a frequency component exists in the original tension signal that is at the same position as the interference frequency or within the tolerance range, it is determined that the component is a false tension component introduced by vortex-induced vibration. A filtering benchmark update signal is generated, and the frequency range to be filtered out is recorded in the filtering benchmark update signal.

[0057] Based on the updated filtering reference signal, band-stop filtering is performed on the original tension signal with the frequency position of the non-true tension component characteristics as the stopband center. This removes signal components that coincide with the vortex-induced vibration interference frequency, retains the frequency components that reflect the true tension changes, and outputs a purified tension reading sequence. The stopband range of the band-stop filter is directly determined by the frequency position of the non-true tension component characteristics; for example, for a specific interference frequency, the stopband is set to the center frequency plus a certain bandwidth.

[0058] After obtaining a clean tension signal, the cable delivery rate can be calculated. First, the adjustment direction and adjustment value are calculated. In one optional implementation, see [link to implementation details]. Figure 6 Step 150 may include the following sub-steps: Step 151: Perform sliding window mean filtering on the purified tension reading sequence to filter out transient fluctuation components and obtain static tension identification components.

[0059] Step 152: Compare the static tension identification component with a preset target tension range; the target tension range includes a lower limit value and an upper limit value of the target tension.

[0060] Step 153: If the static tension identification component is less than the target tension lower limit, the deviation direction is determined to be insufficient tension, and the deviation range is the target tension lower limit minus the static tension identification component.

[0061] Step 154: If the static tension identification component is greater than the target tension upper limit value, the deviation direction is determined to be excessive tension, and the deviation range is the static tension identification component minus the target tension upper limit value.

[0062] Step 155: Generate a rate adjustment demand vector containing an adjustment direction identifier and an adjustment value based on the deviation direction and the deviation magnitude; the adjustment direction identifier is determined by the deviation direction, and the adjustment value is the product of the deviation magnitude and a preset rate adjustment sensitivity coefficient.

[0063] Specifically, the static tension identification component is extracted from the purified tension reading sequence. The static tension identification component is obtained by applying a sliding window mean filter to the purified tension reading sequence. The sliding window covers a preset number of sampling periods, filtering out transient fluctuation components in the tension reading sequence and retaining the mean component that reflects the steady-state stress state of the submarine cable.

[0064] For example, the sliding window mean filtering process is as follows: a fixed-length time window is set, containing a preset number of continuous tension sampling points. The arithmetic mean of all sampling points within the window is calculated as the filtered output for the current moment. Then, the window is moved forward by one sampling period, and the above calculation process is repeated. In this way, transient fluctuation components cancel each other out in the mean calculation due to the alternation of positive and negative values. The remaining mean component is the static tension identification component, which reflects the continuous tension level borne by the submarine cable in the current deployment state.

[0065] In one implementation, the deviation direction is determined using a dual-threshold comparison method. When the static tension identification component is less than the target tension lower limit, the determination result is insufficient tension, and the corresponding adjustment direction indicator indicates that the cable delivery rate should be increased to increase the suspension section length. When the static tension identification component is greater than the target tension upper limit, the determination result is excessive tension, and the corresponding adjustment direction indicator indicates that the cable delivery rate should be decreased to shorten the suspension section length. The rate adjustment demand vector consists of two parts: the adjustment direction indicator and the adjustment value. The adjustment direction indicator is a binary variable, representing acceleration or deceleration respectively. The adjustment value is obtained by multiplying the deviation amplitude by a preset rate adjustment sensitivity coefficient. The sensitivity coefficient is pre-calibrated based on the dynamic response characteristics of the deployment vessel and the sensitivity of the cable tension change. The larger the deviation amplitude, the larger the adjustment value, thereby realizing the correspondence between the degree of tension deviation and the intensity of rate adjustment.

[0066] After obtaining the rate adjustment demand vector, the cable delivery rate of the submarine cable is calculated. In one optional implementation, see [link to relevant documentation]. Figure 7 Step 160 may include the following sub-steps: Step 161: Determine the rate adjustment direction based on the adjustment direction identifier in the rate adjustment demand vector.

[0067] Step 162: Using the adjustment value in the rate adjustment demand vector as the control deviation input, calculate the rate adjustment amount using proportional-integral control.

[0068] Step 163: According to the speed adjustment direction, the current cable output speed is superimposed with the speed adjustment amount to obtain the initial adjustment speed value.

[0069] Step 164: According to the preset cable output rate range, the initial adjustment rate value is limited, and the stable adjusted rate output value is output.

[0070] Specifically, the current cable output rate is read from the rate sensor of the cable output device, and the current cable output rate is associated with the adjustment direction indicator in the rate adjustment demand vector. If the adjustment direction indicator indicates deceleration, the rate adjustment direction is determined to be to reduce the current cable output rate; if the adjustment direction indicator indicates acceleration, the rate adjustment direction is determined to be to increase the current cable output rate.

[0071] Based on the rate adjustment direction and the adjustment value in the rate adjustment demand vector, the rate adjustment process is handled by proportional-integral control. The adjustment value is used as the control deviation input. The control deviation is multiplied by a preset proportional coefficient through the proportional element to obtain the proportional output. The control deviation is accumulated over time through the integral element to obtain the integral output. The proportional output and the integral output are superimposed to obtain the rate adjustment amount.

[0072] Proportional-integral (PI) control is a classic feedback control method in the field of automatic control, consisting of a proportional element and an integral element. The proportional element linearly amplifies the control deviation; the larger the deviation, the larger the output. It has a fast response but suffers from steady-state error. The integral element accumulates the control deviation over time; even if the deviation is small, as long as it persists, the integral output will continuously increase, thus eliminating the steady-state error. In the scenario of adjusting the cable laying rate, the control deviation is the adjustment value in the rate adjustment demand vector, reflecting the degree of deviation between the current tension and the target tension range. The proportional element multiplies the adjustment value by a preset proportional coefficient Kp to obtain an immediate proportional output. The integral element accumulates the adjustment value over the sampling period and multiplies it by the integral coefficient Ki to obtain an integral output that eliminates persistent deviation. Adding the proportional and integral outputs yields the final rate adjustment.

[0073] The rate adjustment amount is superimposed on the current cable output rate. If the rate adjustment direction is to decrease, the rate adjustment amount is subtracted from the current cable output rate. If the rate adjustment direction is to increase, the rate adjustment amount is added to the current cable output rate to obtain the initial adjustment rate value.

[0074] The initial adjustment rate value is compared with the preset upper and lower limits of the cable output rate. If the initial adjustment rate value exceeds the upper limit, the upper limit is used; if the initial adjustment rate value is lower than the lower limit, the lower limit is used, thus obtaining the stable adjusted rate output value.

[0075] Understandably, the initial adjustment rate value is limited before it can be output to the cable delivery equipment. The upper limit of the cable delivery rate is determined comprehensively based on the sailing speed of the deployment vessel, the mechanical load-bearing capacity of the cable delivery equipment, and the maximum allowable deployment rate of the submarine cable. Exceeding this upper limit may lead to unstable cable delivery or equipment overload. The lower limit of the cable delivery rate is determined based on the minimum deployment rate required to maintain the basic tension of the cable suspension section. Falling below this lower limit may lead to cable accumulation or contact with the bottom.

[0076] Please refer to Figure 8 The present invention also provides a cable delivery rate adjustment device for submarine cable laying, see [link to relevant documentation]. Figure 8 The cable delivery rate adjustment device for this submarine cable includes: The locking interval boundary determination unit 210 is used to obtain the current ocean current velocity value and the current suspension section length of the submarine cable, calculate the initial natural frequency offset, and determine the locking interval boundary of vortex-induced vibration.

[0077] The frequency offset determination unit 220 is used to extract the natural frequency features of each order from the spectrum of the real-time vibration frequency of the suspension section, and calculate the frequency offset of each natural frequency feature relative to the boundary of the locking interval.

[0078] The locking interval boundary adjustment unit 230 is used to dynamically adjust the locking interval boundary according to the change in the length of the suspension segment if any of the frequency offsets exceeds a preset offset threshold.

[0079] The tension adjustment unit 240 is used to mark the components of the real-time vibration frequency that fall within the boundary of the locking interval as vortex-induced vibration interference features, and to use the vortex-induced vibration interference features to perform band-stop filtering on the original tension signal of the suspension section, and output the purified tension reading sequence.

[0080] The rate adjustment calculation unit 250 is used to extract the static tension identification component from the purified tension reading sequence, compare it with the preset target tension range, and calculate the rate adjustment demand vector based on the deviation direction and deviation magnitude obtained from the comparison.

[0081] The cable delivery rate calculation unit 260 is used to calculate the rate output value based on the current cable delivery rate and the rate adjustment demand vector, thereby adjusting the cable delivery rate of the submarine cable.

[0082] Please refer to Figure 9 The present invention also provides an electronic device. The electronic device includes a memory 301 and a processor 303, which are electrically connected directly or indirectly to each other to achieve data transmission or interaction. For example, these components can be electrically connected to each other via one or more communication buses 304 or signal lines. The memory 301 can be used to store software programs and modules, and the processor 303 executes the software programs and modules stored in the memory 301, thereby performing various functional applications and data processing.

[0083] Electronic devices can be, but are not limited to, personal computers (PCs), servers, distributed computers, etc. It is understood that electronic devices are not limited to physical servers, but can also be virtual machines on physical servers, virtual machines built on cloud platforms, or other computers that provide the same functionality as the servers or virtual machines. The operating system of the electronic device can be, but is not limited to, Windows systems, Linux systems, etc.

[0084] The memory 301 may be, but is not limited to, random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc.

[0085] The communication connection between the electronic device and an external device is achieved through at least one communication interface 302 (which can be wired or wireless).

[0086] Processor 303 may be an integrated circuit chip with signal processing capabilities. In implementation, the steps of this embodiment can be completed by integrated logic circuits in the hardware of processor 303 or by instructions in software form. Processor 303 may be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it may also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0087] Understandable. Figure 9 The structure shown is for illustrative purposes only; the electronic device may also include components that are more advanced than those shown. Figure 9 The more or fewer components shown, or having the same Figure 9 The different configurations shown. Figure 9 The components shown can be implemented using hardware, software, or a combination thereof.

[0088] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for adjusting the cable delivery rate during submarine cable laying, characterized in that, include: Obtain the current ocean current velocity and the current length of the suspended section of the submarine cable, calculate the initial natural frequency offset, and determine the locking interval boundary of the vortex-induced vibration. Extract the natural frequency features of each order from the spectrum of the real-time vibration frequency of the suspension section, and calculate the frequency offset of each natural frequency feature relative to the boundary of the locking interval. If any of the frequency offsets exceeds a preset offset threshold, the locking interval boundary is dynamically adjusted according to the change in the length of the overhang segment. The components of the real-time vibration frequency that fall within the boundary of the locked interval are marked as vortex-induced vibration interference features. The original tension signal of the suspension section is band-stop filtered using the vortex-induced vibration interference features to output a purified tension reading sequence. The static tension identification component is extracted from the purified tension reading sequence and compared with the preset target tension range. Based on the deviation direction and deviation magnitude obtained from the comparison, the rate adjustment demand vector is calculated. Based on the current cable delivery rate and the rate adjustment demand vector, the rate output value is calculated, and the cable delivery rate of the submarine cable is adjusted accordingly.

2. The method according to claim 1, characterized in that, Calculate the initial natural frequency offset and determine the locking interval boundary of vortex-induced vibration, including: Based on the current ocean current velocity and the cable diameter, the vortex shedding frequency is calculated using the Strocha number formula. The difference between the vortex shedding frequency and the preset natural vibration fundamental frequency of the suspended section is calculated to obtain the initial natural frequency offset. The excitation frequency range of vortex-induced vibration is determined based on the vortex shedding frequency. The initial natural frequency offset is superimposed on the excitation frequency range to obtain the locking interval boundary of vortex-induced vibration.

3. The method according to claim 1, characterized in that, Extract the natural frequency features of each order from the spectrum of the real-time vibration frequency of the suspension section, and calculate the frequency offset of each natural frequency feature relative to the boundary of the locked interval, including: The frequency domain vibration spectrum is obtained by performing a fast Fourier transform on the real-time vibration frequency of the suspended section. Identify the peak positions in the frequency domain vibration spectrum whose amplitude exceeds a preset noise threshold, and extract the natural frequency features of each order; For each inherent frequency feature, the absolute value of the difference between the inherent frequency feature and the lower boundary value and the upper boundary value of the locked interval are calculated respectively, and the smallest absolute value of the difference is taken as the frequency offset corresponding to that level.

4. The method according to claim 1, characterized in that, If any of the frequency offsets exceeds a preset offset threshold, the locking interval boundary is dynamically adjusted based on the change in the length of the overhang segment, including: The current length of the overhanging segment is compared with the preset reference length of the overhanging segment to obtain the length change. Based on the inverse relationship between the length of the reference suspension section and the corresponding reference natural frequency, the length change is converted into a frequency compensation value. The frequency compensation value is added to the lower boundary value and the upper boundary value of the locked interval boundary to obtain the adjusted locked interval boundary.

5. The method according to claim 1, characterized in that, The components of the real-time vibration frequency that fall within the boundary of the locked interval are marked as vortex-induced vibration interference features. These vortex-induced vibration interference features are then used to perform band-stop filtering on the original tension signal of the suspended section, outputting a purified tension reading sequence, including: Each frequency component of the real-time vibration frequency is compared with the boundary of the locking interval, and the frequency component that falls into the boundary of the locking interval is marked as the vortex-induced vibration interference component. Based on the frequency position and amplitude of each vortex-induced vibration interference component, the characteristics of the non-real tension component are constructed. The frequency components of the acquired original tension signal of the suspended section are compared with the frequency positions in the features of the non-real tension components. If the original tension signal contains a component with the same frequency position as or within the tolerance range of the non-real tension component feature, a filter reference update signal with the frequency position of the non-real tension component feature as the stopband center is generated. The original tension signal is subjected to band-stop filtering based on the filter reference update signal, and a purified tension reading sequence is output.

6. The method according to claim 1, characterized in that, The static tension identification component is extracted from the purified tension reading sequence and compared with a preset target tension range. Based on the deviation direction and magnitude obtained from the comparison, the rate adjustment demand vector is calculated, including: The purified tension reading sequence is subjected to sliding window mean filtering to remove transient fluctuation components and obtain static tension identification components. The static tension identification component is compared with a preset target tension range; the target tension range includes a lower limit value and a higher limit value of the target tension. If the static tension identification component is less than the target tension lower limit, the deviation direction is determined to be insufficient tension, and the deviation magnitude is the target tension lower limit minus the static tension identification component. If the static tension identification component is greater than the target tension upper limit, the deviation direction is determined to be excessive tension, and the deviation range is the static tension identification component minus the target tension upper limit. Based on the deviation direction and the deviation magnitude, a rate adjustment demand vector containing an adjustment direction identifier and an adjustment value is generated; the adjustment direction identifier is determined by the deviation direction, and the adjustment value is the product of the deviation magnitude and a preset rate adjustment sensitivity coefficient.

7. The method according to claim 6, characterized in that, Based on the current cable delivery rate and the rate adjustment demand vector, calculate the rate output value to adjust the cable delivery rate, including: The rate adjustment direction is determined based on the adjustment direction identifier in the rate adjustment demand vector; Using the adjustment value in the rate adjustment demand vector as the control deviation input, the rate adjustment is calculated using proportional-integral control. According to the speed adjustment direction, the current cable output speed is superimposed with the speed adjustment amount to obtain the initial adjustment speed value; Based on the preset cable output rate range, the initial adjustment rate value is limited, and a stable adjusted rate output value is output.

8. A cable delivery rate adjustment device for submarine cable laying, characterized in that, include: The locking interval boundary determination unit is used to obtain the current ocean current velocity value and the current suspension section length of the submarine cable, calculate the initial natural frequency offset, and determine the locking interval boundary of vortex-induced vibration. The frequency offset determination unit is used to extract the natural frequency features of each order from the spectrum of the real-time vibration frequency of the suspension section, and calculate the frequency offset of each natural frequency feature relative to the boundary of the locking interval. A locking interval boundary adjustment unit is used to dynamically adjust the locking interval boundary according to the change in the length of the suspended segment if any of the frequency offsets exceeds a preset offset threshold. The tension adjustment unit is used to mark the components of the real-time vibration frequency that fall within the boundary of the locking interval as vortex-induced vibration interference features, and to use the vortex-induced vibration interference features to perform band-stop filtering on the original tension signal of the suspension section, and output the purified tension reading sequence. The rate adjustment calculation unit is used to extract the static tension identification component from the purified tension reading sequence, compare it with the preset target tension range, and calculate the rate adjustment demand vector based on the deviation direction and deviation magnitude obtained from the comparison. The cable delivery rate calculation unit is used to calculate the rate output value based on the current cable delivery rate and the rate adjustment demand vector, thereby adjusting the cable delivery rate of the submarine cable.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the method according to any one of claims 1 to 7.

10. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method described in any one of claims 1 to 7.

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