Vibration test and strength checking method and system for swinging table of key component of marine transportation equipment

Abstract

The invention provides a vibration test and strength checking method and system for a key component swing table of marine transportation equipment, and is applied to the technical field of offshore wind power. The method comprises the following steps: determining an actual cycle action frequency based on a peak frequency of a displacement power spectrum of a key component in marine transportation equipment under each degree of freedom and actual marine transportation time; determining a corresponding damage equivalent relationship based on the displacement power spectrum and the actual cycle action times, and determining a corresponding equivalent test load and test duration based on the damage equivalent relationship; performing amplitude adjustment on the equivalent test load based on the amplitude adjustment coefficient to obtain a corresponding test load amplitude; and based on the test load amplitude, the test duration and the maximum test frequency of the swing table under the corresponding degree of freedom, carrying out a swing table vibration test on the key component in the marine transportation equipment. The method solves the problems that the sea transportation simulation analysis result of the equipment cannot be accurately evaluated and the internal damage risk of the equipment cannot be found in time.

Description

Technical Field

[0001] The present invention relates to the technical field of offshore wind power, and specifically relates to a method and system for vibration testing and strength checking of a swing table, which is a key component of a marine transportation device. Background Art

[0002] Offshore wind power is a strategic emerging technology that deeply integrates wind power technology and ocean engineering technology, and is an important direction for China to build a new energy system. The electrical equipment required for the implementation of offshore wind power needs to be transported to the destination by sea.

[0003] During the sea transportation of the equipment, the equipment is mainly affected by wave loads. Through the transmission of wave loads by the bottom structure, each component in the equipment is subjected to large vibration impacts, and internal damage is likely to occur to components with large displacements. Currently, experimental evaluations are generally carried out through the sea transportation simulation analysis of electrical equipment to discover in advance the parts that may cause damage risks during actual sea transportation. However, currently, due to reasons such as limited specifications of vibration tables or swing tables, physical test data support cannot be provided, resulting in the inability to accurately evaluate the results of sea transportation simulation analysis, and thus the problem of being unable to timely discover the internal damage risks of the equipment. Summary of the Invention

[0004] In order to overcome the problems of being unable to accurately evaluate the results of sea transportation simulation analysis of equipment and being unable to timely discover the internal damage risks of the equipment, the present invention provides a method and system for vibration testing and strength checking of a swing table, which is a key component of a marine transportation device.

[0005] On the one hand, the present invention provides a method for vibration testing of a swing table, which is a key component of a marine transportation device, including:

[0006] Determining the actual number of cyclic actions in each degree of freedom based on the peak frequency of the displacement power spectrum and the actual sea transportation time of the key component in the marine transportation device in each degree of freedom;

[0007] Determining the damage equivalence relationship in each degree of freedom based on the displacement power spectrum and the actual number of cyclic actions in each degree of freedom, and determining the equivalent test load and test duration in the corresponding degree of freedom based on the damage equivalence relationship in each degree of freedom;

[0008] Adjusting the amplitude of the equivalent test load based on the amplitude adjustment coefficient in each degree of freedom to obtain the test load amplitude in the corresponding degree of freedom;

[0009] Performing a vibration test of the swing table, which is a key component of the marine transportation device, based on the test load amplitude, test duration, and maximum test frequency of the swing table in the corresponding degree of freedom in each degree of freedom;

[0010] Among them, the amplitude adjustment coefficient is determined based on the difference between the dynamic amplification coefficient of the wave load and the dynamic amplification coefficient of the shaking table test load.

[0011] Optionally, before determining the actual number of cyclic actions in each degree of freedom based on the peak frequency of the displacement power spectrum of the key components in the marine equipment in each degree of freedom and the actual marine transportation time, it further includes:

[0012] Based on the simulation analysis of the transportation ship of the marine equipment, the ship amplitude response operator is obtained, and based on the wave spectrum of the navigation sea area and the ship amplitude response operator, the motion power spectrum of the ship's center of gravity is calculated;

[0013] Taking the motion power spectrum of the ship's center of gravity as the input, the finite element model of the bearing mechanism of the marine equipment is simulated and analyzed to obtain the root displacement power spectrum of the marine equipment;

[0014] Taking the root displacement power spectrum of the marine equipment as the input, the finite element model of the marine equipment is simulated and analyzed to obtain the displacement power spectra of the key components in the marine equipment in each degree of freedom.

[0015] Optionally, determining the damage equivalence relationship in each degree of freedom based on the displacement power spectrum and the actual number of cyclic actions in each degree of freedom includes:

[0016] Based on the displacement power spectrum in each degree of freedom and the actual number of cyclic actions in each degree of freedom, using the three - interval method, calculate the load amplitudes and the number of test cyclic actions corresponding to each interval in each degree of freedom;

[0017] Based on the load amplitudes corresponding to each interval in each degree of freedom and the S - N curve relationship of the key components in the marine equipment, determine the fatigue life corresponding to each interval in each degree of freedom;

[0018] Based on the number of test cyclic actions and the fatigue life corresponding to each interval in each degree of freedom, using Miner's law and the fatigue damage equivalence principle, determine the equivalent interval and the equivalent magnification factor in the corresponding degree of freedom, so that the fatigue damage of the load amplitude corresponding to the equivalent interval under the test duration corresponding to the equivalent magnification factor is equivalent to the sum of the fatigue damages of the load amplitudes corresponding to each interval, thereby obtaining the damage equivalence relationship in the corresponding degree of freedom.

[0019] Among them, the equivalent interval belongs to the three intervals corresponding to the three - interval method.

[0020] Optionally, the load amplitudes corresponding to each interval in each degree of freedom include the load amplitude corresponding to one - time standard deviation of the displacement power spectrum in each degree of freedom, the load amplitude corresponding to two - time standard deviation of the displacement power spectrum in each degree of freedom, and the load amplitude corresponding to three - time standard deviation of the displacement power spectrum in each degree of freedom.

[0021] Optionally, the damage equivalence relationship is as follows:

[0022]

[0023] Where D is the sum of the fatigue damages corresponding to the load amplitudes in each interval, n 1σ 、n 2σ 、n 3σ are the number of test cycle actions corresponding to the load amplitudes of one standard deviation, two standard deviations, and three standard deviations respectively; N 1σ 、N 2σ 、N 3σ are the fatigue lives corresponding to the load amplitudes of one standard deviation, two standard deviations, and three standard deviations respectively; a is the equivalent magnification factor, n xσ 、N xσ are the number of test cycle actions and fatigue lives corresponding to the load amplitudes in the equivalent interval respectively; K is the load response relationship coefficient of the key components in the marine equipment, C and k are material constants respectively, and A1, A2, and A3 are the load amplitudes corresponding to one standard deviation, two standard deviations, and three standard deviations respectively.

[0024] Optionally, determining the equivalent test load and test duration corresponding to each degree of freedom based on the damage equivalence relationship for each degree of freedom includes:

[0025] Taking the load amplitude corresponding to the equivalent interval under each degree of freedom as the equivalent load amplitude under the corresponding degree of freedom;

[0026] Based on the number of test cycle actions corresponding to the equivalent interval in the damage equivalence relationship under each degree of freedom and the maximum test frequency of the shaking table under the corresponding degree of freedom, determining the test duration of the equivalent interval under the corresponding degree of freedom;

[0027] Based on the product of the test duration of the equivalent interval under each degree of freedom and the equivalent magnification factor, determining the test duration under the corresponding degree of freedom.

[0028] Optionally, before adjusting the amplitude of the original load determined based on the displacement power spectrum under each degree of freedom by the amplitude adjustment factor under the corresponding degree of freedom to obtain the test load amplitude under the corresponding degree of freedom, it further includes:

[0029] Based on the displacement power spectrum of the key components in the marine equipment under each degree of freedom and the natural frequency of the corresponding degree of freedom, determining the dynamic amplification factor of the wave load under the corresponding degree of freedom;

[0030] Based on the maximum test frequency of the shaking table under each degree of freedom and the natural frequency of the key components in the marine equipment under the corresponding degree of freedom, determining the dynamic amplification factor of the test load of the shaking table under the corresponding degree of freedom;

[0031] Determine the amplitude adjustment factor for each degree of freedom based on the ratio of the dynamic amplification factor of the shaking table test load to the dynamic amplification factor of the wave load for each degree of freedom.

[0032] Optionally, after adjusting the amplitude of the equivalent test load based on the amplitude adjustment factor for each degree of freedom to obtain the test load amplitude for each degree of freedom, it further includes:

[0033] For each degree of freedom, if the corresponding test load amplitude is less than the swing amplitude limit of the shaking table, calculate the ratio of the swing amplitude limit of the shaking table to the corresponding test load amplitude as the original amplification factor;

[0034] Determine the scaling correspondence between the load amplitude and the test duration of the key components in the marine equipment based on the principle of loss equivalence;

[0035] Adjust the test duration for each degree of freedom based on the original amplification factor and the scaling correspondence between the load amplitude and the test duration of the key components in the marine equipment to obtain the adjusted test duration for each degree of freedom;

[0036] The shaking table vibration test of the key components in the marine equipment based on the test load amplitude, test duration, and maximum test frequency of the shaking table in each degree of freedom includes:

[0037] Conduct the shaking table vibration test of the key components in the marine equipment based on the swing amplitude limit, adjusted test duration, and maximum test frequency of the shaking table in each degree of freedom.

[0038] On the other hand, the present invention also provides a method for checking the strength of key components of marine equipment, including:

[0039] Obtain the test results of the shaking table vibration test of the key components in the marine equipment described in any one of the above;

[0040] Conduct corresponding strength checks based on the test results of the shaking table vibration test of the key components in the marine equipment and the strength requirements of the key components in the marine equipment.

[0041] Optionally, the marine equipment is a flexible DC converter valve; the key component is the top valve module of the flexible DC converter valve.

[0042] On the other hand, the present invention also provides a shaking table vibration test system for key components of marine equipment, including:

[0043] A cycle number determination module for determining the actual number of cyclic actions for each degree of freedom based on the peak frequency of the displacement power spectrum and the actual marine transportation time of the key components in the marine equipment for each degree of freedom;

[0044] An equivalent conversion module, which is used to determine the damage equivalent relationship of each degree of freedom based on the displacement power spectrum and the actual number of cyclic actions under each degree of freedom, and determine the equivalent test load and test duration corresponding to each degree of freedom based on the damage equivalent relationship of each degree of freedom;

[0045] An amplitude adjustment module, which is used to adjust the amplitude of the equivalent test load based on the amplitude adjustment coefficient under each degree of freedom to obtain the test load amplitude corresponding to each degree of freedom;

[0046] A vibration test module, which is used to perform a shaking table vibration test on the key components in the marine equipment based on the test load amplitude, test duration under each degree of freedom, and the maximum test frequency of the shaking table under the corresponding degree of freedom;

[0047] Wherein, the amplitude adjustment coefficient is determined based on the difference between the dynamic amplification coefficient of the wave load and the dynamic amplification coefficient of the shaking table test load.

[0048] Optionally, it further includes a simulation analysis module, and the simulation analysis module is used for:

[0049] Based on the simulation analysis of the transport ship of the marine equipment, a ship amplitude response operator is obtained, and based on the wave spectrum of the navigation sea area and the ship amplitude response operator, the motion power spectrum of the ship's center of gravity is calculated;

[0050] Taking the motion power spectrum of the ship's center of gravity as the input, performing a simulation analysis on the finite element model of the bearing mechanism of the marine equipment to obtain the root displacement power spectrum of the marine equipment;

[0051] Taking the root displacement power spectrum of the marine equipment as the input, performing a simulation analysis on the finite element model of the marine equipment to obtain the displacement power spectrum of the key components in the marine equipment under each degree of freedom.

[0052] Optionally, the equivalent conversion module includes:

[0053] A sub-module for calculating in intervals, which is used to calculate the load amplitude and the number of test cyclic actions corresponding to each interval under each degree of freedom by using the three-interval method based on the displacement power spectrum under each degree of freedom and the actual number of cyclic actions under each degree of freedom; and determine the fatigue life corresponding to each interval under each degree of freedom based on the load amplitude corresponding to each interval under each degree of freedom and the S-N curve relationship of the key components in the marine equipment;

[0054] An equivalent calculation sub-module, which is used to determine the equivalent interval and equivalent magnification corresponding to each degree of freedom based on the number of test cycle actions and fatigue life corresponding to each interval under each degree of freedom, by using Miner's law and the principle of equivalent fatigue damage, so that the fatigue damage of the load amplitude corresponding to the equivalent interval under the test holding time corresponding to the equivalent magnification is equivalent to the sum of the fatigue damages of the load amplitudes corresponding to each interval, thereby obtaining the damage equivalent relationship corresponding to each degree of freedom.

[0055] Among them, the equivalent interval belongs to the three intervals corresponding to the three-interval method.

[0056] Optionally, the load amplitudes corresponding to each interval under each degree of freedom include the load amplitude corresponding to one standard deviation of the displacement power spectrum under each degree of freedom, the load amplitude corresponding to two standard deviations of the displacement power spectrum under each degree of freedom, and the load amplitude corresponding to three standard deviations of the displacement power spectrum under each degree of freedom.

[0057] Optionally, the damage equivalent relationship is as follows:

[0058]

[0059] Among them, D is the sum of the fatigue damages of the load amplitudes corresponding to each interval, n 1σ 、n 2σ 、n 3σ are the number of test cycle actions corresponding to the load amplitudes of one standard deviation, two standard deviations, and three standard deviations respectively; N 1σ 、N 2σ 、N 3σ are the fatigue lives corresponding to the load amplitudes of one standard deviation, two standard deviations, and three standard deviations respectively; a is the equivalent magnification, n xσ 、N xσ are the number of test cycle actions and fatigue life corresponding to the load amplitude of the equivalent interval respectively; K is the load response relationship coefficient of the key components in the marine equipment, C and k are material constants respectively, and A1, A2, and A3 are the load amplitudes corresponding to one standard deviation, two standard deviations, and three standard deviations respectively.

[0060] Optionally, the equivalent conversion module further includes an equivalent conversion sub-module, and the equivalent conversion sub-module is used for:

[0061] Taking the load amplitude corresponding to the equivalent interval under each degree of freedom as the equivalent load amplitude corresponding to each degree of freedom;

[0062] Based on the number of test cycle actions corresponding to the equivalent interval in the damage equivalent relationship under each degree of freedom and the maximum test frequency of the shaking table under the corresponding degree of freedom, determining the test holding time of the equivalent interval under the corresponding degree of freedom;

[0063] Determine the test duration corresponding to each degree of freedom based on the product of the test duration and the equivalent magnification factor in the equivalent interval for each degree of freedom.

[0064] Optionally, the amplitude adjustment module includes:

[0065] A wave amplification factor determination sub-module, configured to determine the dynamic amplification factor of the wave load corresponding to each degree of freedom based on the displacement power spectrum of the key components in the marine equipment in each degree of freedom and the natural frequency corresponding to each degree of freedom;

[0066] A test amplification factor determination sub-module, configured to determine the dynamic amplification factor of the test load of the shaking table corresponding to each degree of freedom based on the maximum test frequency of the shaking table in each degree of freedom and the natural frequency of the key components in the marine equipment corresponding to each degree of freedom;

[0067] An adjustment factor determination sub-module, configured to determine the amplitude adjustment factor corresponding to each degree of freedom based on the ratio of the dynamic amplification factor of the test load of the shaking table to the dynamic amplification factor of the wave load corresponding to each degree of freedom.

[0068] Optionally, it further includes a parameter scaling module, and the parameter scaling module includes:

[0069] An original coefficient calculation sub-module, for each degree of freedom, if the corresponding test load amplitude is less than the shaking amplitude limit of the shaking table, calculate the ratio of the shaking amplitude limit of the shaking table to the corresponding test load amplitude as the original amplification factor;

[0070] A corresponding relationship determination sub-module, configured to determine the scaling corresponding relationship between the load amplitude and the test duration of the key components in the marine equipment based on the loss equivalence principle;

[0071] A duration adjustment sub-module, configured to adjust the test duration corresponding to each degree of freedom based on the original amplification factor and the scaling corresponding relationship between the load amplitude and the test duration of the key components in the marine equipment, and obtain the adjusted test duration corresponding to each degree of freedom;

[0072] The vibration test module is specifically configured to:

[0073] Conduct a shaking table vibration test on the key components of the marine equipment based on the shaking amplitude limit of the shaking table, the adjusted test duration, and the maximum test frequency of the shaking table corresponding to each degree of freedom.

[0074] On the other hand, the present invention also provides a strength checking system for key components of marine equipment, including:

[0075] A result acquisition module, configured to acquire the test results of the shaking table vibration test of the key components of the marine equipment described in any one of claims 1-8;

[0076] A strength checking module is used to perform corresponding strength checking based on the test results of the swing table vibration test of key components in the marine equipment and the strength requirements of the key components in the marine equipment.

[0077] Optionally, the marine equipment is a flexible DC converter valve; the key component is the top valve module of the flexible DC converter valve.

[0078] On the other hand, the present invention also provides an electronic device, including: at least one processor and a memory; the memory and the processor are connected through a bus;

[0079] The memory is used to store one or more programs;

[0080] When the one or more programs are executed by the at least one processor, the swing table vibration test method or the strength checking method of the key components of the marine equipment described in any one of the above is implemented.

[0081] On the other hand, the present invention also provides a readable storage medium with an execution program stored thereon. When the execution program is executed, the swing table vibration test method or the strength checking method of the key components of the marine equipment described in any one of the above is implemented.

[0082] Compared with the prior art, the beneficial effects of the present invention are:

[0083] The present invention provides a swing table vibration test method and system for key components of marine equipment. Based on the displacement power spectrum and the actual number of cyclic actions of key components in the marine equipment in each degree of freedom, the damage equivalent relationship of each degree of freedom is determined. Based on the damage equivalent relationship of each degree of freedom, the equivalent test load and test duration corresponding to the corresponding degree of freedom are determined; by using the fatigue damage equivalent principle and the swing table capacity limit to determine the test parameters of the vibration test to carry out the physical test, the wave load can be equivalently converted into physical test parameters, so as to reflect the structural safety of the key components of the equipment during sea transportation through the test results and avoid the risk of internal structural damage of the marine equipment; by using the test results to evaluate the accuracy of the marine simulation analysis, it can lay a foundation for improving the accuracy of numerical simulation; and compared with the previous physical tests, the test duration can be greatly shortened and the test efficiency can be improved.

[0084] The present invention determines the amplitude adjustment coefficient based on the difference between the dynamic amplification coefficient of the wave load and the dynamic amplification coefficient of the swing table test load. The equivalent test load is amplitude-adjusted based on the amplitude adjustment coefficient in each degree of freedom. Through amplitude adjustment, the difference between the low-frequency wave load in the actual sea transportation process and the high-frequency vibration load in the test process is compensated, improving the accuracy of the test results, and further improving the evaluation accuracy of the marine simulation analysis. Description of the Drawings

[0085] Figure 1 Schematic flow diagram of a method for shaking table vibration test of key components of a marine equipment according to the present invention;

[0086] Figure 2 Schematic diagram of displacement power spectrum under a vertical heaving degree of freedom as an example according to the present invention;

[0087] Figure 3 Schematic diagram of a finite element model of a converter valve as an example according to the present invention;

[0088] Figure 4 Schematic diagram of a finite element model of a valve module at the top of a valve tower as an example according to the present invention;

[0089] Figure 5 Schematic diagram of the location of key components of a flexible DC converter valve as an example according to the present invention;

[0090] Figure 6 Schematic diagram of the structure of an electronic device according to the present invention. Detailed implementation manners

[0091] The following further elaborates on the detailed implementation manners of the present invention in conjunction with the accompanying drawings.

[0092] Embodiment 1

[0093] A method for shaking table vibration test of key components of a marine equipment provided by the present invention, as shown in Figure 1 shown, includes:

[0094] Step S110, determining the actual number of cyclic actions for each degree of freedom based on the peak frequency of the displacement power spectrum and the actual marine time of the key components in the marine equipment for each degree of freedom;

[0095] Step S120, determining the damage equivalence relationship for each degree of freedom based on the displacement power spectrum and the actual number of cyclic actions for each degree of freedom, and determining the equivalent test load and test duration for the corresponding degree of freedom based on the damage equivalence relationship for each degree of freedom;

[0096] Step S130, adjusting the amplitude of the equivalent test load based on the amplitude adjustment coefficient for each degree of freedom to obtain the test load amplitude for the corresponding degree of freedom;

[0097] Step S140, performing a shaking table vibration test on the key components in the marine equipment based on the test load amplitude, test duration, and maximum test frequency of the shaking table for each degree of freedom.

[0098] In the present exemplary embodiment, the marine equipment may be large electrical equipment for various maritime transports, and the key component may be the top structure of the equipment, and there is an obvious interaction relationship between its top structure and the overall structure. For example, the marine equipment is a flexible DC converter valve; the key component may be the key functional module of the equipment or the part with large load vibration, for example, the valve module at the top of the valve tower of the flexible DC converter valve. The degrees of freedom for the key component in the marine equipment to conduct the sway table vibration test may include six degrees of freedom such as surge, sway, heave, roll, pitch, and yaw. For each degree of freedom, the above steps are required to determine the vibration test parameters, namely the test load, test duration, and test input frequency. To improve the test efficiency, for each degree of freedom, the maximum test frequency that the sway table can provide may be selected as the test input frequency. The actual number of cyclic actions can be determined by the product of the peak frequency of the displacement power spectrum of the key component in the marine equipment and the actual marine time. The damage equivalence relationship for each degree of freedom can be established by using the fatigue damage equivalence principle and the three-interval method. The fatigue damage equivalence principle is an important concept in fatigue analysis, which is used to evaluate the damage accumulation of materials or structures under cyclic loads. Its core idea is to convert the complex load history into an equivalent simple load, and simplify the complex load into an equivalent constant amplitude load to produce the same damage effect. Common methods include the root mean square method, the rain flow counting method, etc. The three-interval method is the three-interval method based on the Gaussian distribution proposed by Steinberg, which is a commonly used fatigue life prediction method, mainly used to analyze the fatigue life of materials under different stress levels. By assuming that the random excitation received by the structure follows the Gaussian distribution, this method uses the stress levels of 1σ, 2σ, and 3σ and the vibration frequency, where σ is the stress standard deviation, and combines the S-N curve and the Miner criterion to calculate the fatigue damage, so as to predict the fatigue life. The amplitude adjustment coefficient is determined based on the difference between the dynamic amplification coefficient of the wave load and the dynamic amplification coefficient of the sway table test load. The sway table vibration test of the key component in the marine equipment may be to conduct each single-degree-of-freedom vibration test separately, and when the equipment capacity permits, the vibration tests of each degree of freedom may also be carried out simultaneously. The present invention uses the fatigue damage equivalence principle and the three-interval method to determine the damage equivalence relationship for each degree of freedom, determines the vibration test parameters based on the damage equivalence relationship, and the design process is convenient and fast; the test results can directly reflect the structural safety of the key components of the equipment during maritime transport, can be used to update the finite element model of the marine equipment, and lay a foundation for improving the accuracy of numerical simulation; and this test method can greatly shorten the test duration and improve the test efficiency. The difference between the dynamic amplification process of the wave load and the dynamic amplification process of the sway table test load can also be compensated by the amplitude adjustment coefficient to further improve the accuracy of the test results and fill the blank of the test data of current marine transport equipment (such as flexible DC converter valves).

[0099] In some exemplary embodiments, before determining the actual number of cyclic actions in each degree of freedom based on the peak frequencies of the displacement power spectra of the key components in the marine equipment and the actual marine transportation time in step S110, the following steps are further included:

[0100] Based on the simulation analysis of the transportation ship of the marine equipment, a ship amplitude response operator is obtained. Based on the wave spectrum of the navigation sea area and the ship amplitude response operator, the motion power spectrum of the ship's center of gravity is calculated;

[0101] Taking the motion power spectrum of the ship's center of gravity as the input, a finite element model of the load-bearing mechanism of the marine equipment is simulated and analyzed to obtain the root displacement power spectrum of the marine equipment;

[0102] Taking the root displacement power spectrum of the marine equipment as the input, a finite element model of the marine equipment is simulated and analyzed to obtain the displacement power spectra of the key components in the marine equipment in each degree of freedom.

[0103] In this exemplary embodiment, the transportation ship of the equipment is simulated and analyzed by hydrodynamic analysis software to obtain a ship amplitude response operator (Response Amplitude Operator, RAO). According to the wave spectrum of the ship's navigation sea area and the RAO, the motion power spectrum of the ship's center of gravity is calculated. The calculation formula is as follows:

[0104] S R (ω) = RAO 2 (ω) * S ω (ω) (1)

[0105] In the formula, S R (ω) is the motion power spectrum of the ship's center of gravity, RAO(ω) is the ship amplitude response operator, S ω (ω) is the wave spectrum of the ship's navigation sea area, and ω is the load frequency. After obtaining the motion power spectrum of the ship's center of gravity, taking the motion power spectrum of the ship's center of gravity as the input, a finite element model simulation analysis of the lower load-bearing mechanism where the marine equipment is placed is carried out to obtain the root displacement or acceleration power spectrum of the marine equipment (such as the converter valve tower). Then, taking the root displacement or acceleration power spectrum of the marine equipment as the input, a finite element model simulation analysis of the marine equipment (converter valve tower) is carried out to obtain the displacement power spectra of the key components in the marine equipment in each degree of freedom. For example, the six-degree-of-freedom (surge, sway, heave, roll, pitch, yaw) displacement power spectrum of the top valve module of the converter valve is obtained.

[0106] In some embodiments, the displacement power spectra of key components in a marine device at each degree of freedom can also be converted into simple harmonic waves as the input of the test for calculation. Specifically, assuming that the displacement power spectrum follows a narrowband distribution, the power spectrum is approximated as a simple harmonic wave of a single frequency. For example, the displacement power spectrum at the bottom of the valve module in the heave degree of freedom is as Figure 2 shown, and its spectral peak frequency is 0.1039 Hz. The root mean square value of the spectral area represents the displacement value. Therefore, the displacement power spectrum of Figure 2 can be approximately converted into a simple harmonic wave with a frequency of 0.1039 Hz and an amplitude equal to the root mean square value of the spectral area.

[0107] In some exemplary embodiments, step S120 of determining the damage equivalence relationship for each degree of freedom based on the displacement power spectrum and the actual number of cyclic actions at each degree of freedom, using the fatigue damage equivalence principle and the three-interval method, includes:

[0108] Based on the displacement power spectrum at each degree of freedom and the actual number of cyclic actions at each degree of freedom, using the three-interval method, calculate the load amplitude and the number of test cyclic actions corresponding to each interval at each degree of freedom;

[0109] Based on the load amplitude corresponding to each interval at each degree of freedom and the S-N curve relationship of the key components in the marine device, determine the fatigue life corresponding to each interval at each degree of freedom;

[0110] Based on the number of test cyclic actions and the fatigue life corresponding to each interval at each degree of freedom, using Miner's law and the fatigue damage equivalence principle, determine the equivalent interval and the equivalent magnification corresponding to the degree of freedom, so that the fatigue damage of the load amplitude corresponding to the equivalent interval under the test holding time corresponding to the equivalent magnification is equivalent to the sum of the fatigue damages of the load amplitudes corresponding to each interval, thereby obtaining the damage equivalence relationship corresponding to the degree of freedom.

[0111] Among them, the equivalent interval belongs to the three intervals corresponding to the three-interval method.

[0112] In the present exemplary embodiment, for each degree of freedom, the load amplitudes corresponding to each interval include the load amplitude corresponding to one standard deviation of the displacement power spectrum (1σ stress level), the load amplitude corresponding to two standard deviations of the displacement power spectrum (2σ stress level), and the load amplitude corresponding to three standard deviations of the displacement power spectrum (3σ stress level) under this degree of freedom. For each degree of freedom, the fatigue calculation is carried out using Miner's law. When the load amplitude is one standard deviation, the number of test cycles is the total number of cyclic actions at the first set ratio. For example, the number of test cycles is 0.6831 * the total number of cyclic actions; when the load amplitude is two standard deviations, the number of test cycles is the total number of cyclic actions at the second set ratio. For example, the number of test cycles is 0.271 * the total number of cyclic actions; when the load amplitude is three standard deviations, the number of test cycles is the total number of cyclic actions at the third set ratio. For example, the number of test cycles is 0.0433 * the total number of cyclic actions. That is, the number of cyclic actions at 1σ, 2σ, and 3σ stress levels are respectively a certain proportion of the actual number of cyclic actions (i.e., the total number of cyclic actions). For example, the first set ratio is 0.683, the second set ratio is 0.271, and the third set ratio is 0.0433. Assuming a linear relationship between the stress response and the input load, the fatigue life of each interval can be obtained based on the S-N curve relationship and this linear relationship, as shown below:

[0113] S k N = C (2)

[0114] S = KA (3)

[0115]

[0116] Among them, Equation (2) is the S-N curve relationship, S is the fatigue strength or stress, N is the fatigue life, Equation (3) is the linear relationship between the stress response and the input load, and Equation (4) is the fatigue life calculation formula; N 1σ 、N 2σ 、N 3σ are the fatigue lives corresponding to the load amplitudes of one standard deviation, two standard deviations, and three standard deviations respectively; K is the load-response linear relationship coefficient of the key components in the marine equipment, C and k are material constants respectively, and A1, A2, and A3 are the load amplitudes corresponding to one standard deviation, two standard deviations, and three standard deviations respectively.

[0117] Using Miner's law and the fatigue damage equivalence principle, substituting the number of test cyclic actions corresponding to each interval and the fatigue life in Equation (4) into the following fatigue damage calculation formula (5), the damage equivalent to the sum of the fatigue damages corresponding to the load amplitudes of each interval can be obtained under the equivalent interval and equivalent magnification, and the corresponding damage equivalence relationship is shown in Equation (6).

[0118]

[0119] where D is the sum of the fatigue damages corresponding to the load amplitudes in each interval, and n 1σ , n 2σ , n 3σ are the number of test cycle actions corresponding to the load amplitudes of one standard deviation, two standard deviations, and three standard deviations respectively; a is the equivalent multiple, and n xσ , N xσ are the number of test cycle actions and the fatigue life corresponding to the load amplitude in the equivalent interval respectively. a, n xσ , N xσ are determined through the formula derivation process. For example, when the material constant k = 2, a = 2, n xσ = n 2′ , N xσ = N 2σ , that is, the damage after doubling the test duration of the load corresponding to two standard deviations is equivalent to the sum of the damages corresponding to the loads of one, two, and three standard deviations. In this way, when conducting vibration tests, it is not necessary to conduct tests on the loads corresponding to one, two, and three standard deviations separately, but only to conduct tests according to the load corresponding to two standard deviations to achieve the equivalent damage effect, greatly simplifying the test process, shortening the test duration, and improving the test efficiency.

[0120] In some exemplary embodiments, the determining the equivalent test load and test duration corresponding to each degree of freedom based on the damage equivalence relationship in step S120 includes:

[0121] Taking the load amplitude corresponding to the equivalent interval under each degree of freedom as the equivalent load amplitude corresponding to each degree of freedom;

[0122] Based on the number of test cycle actions corresponding to the equivalent interval in the damage equivalence relationship under each degree of freedom and the maximum test frequency of the shaking table under the corresponding degree of freedom, determining the test duration of the equivalent interval under the corresponding degree of freedom;

[0123] Based on the product of the test duration of the equivalent interval under each degree of freedom and the equivalent multiple, determining the test duration under the corresponding degree of freedom.

[0124] In the present exemplary embodiment, the load amplitude corresponding to the equivalent interval under each degree of freedom is used as the equivalent load amplitude under the corresponding degree of freedom, that is, the load amplitude of the finally determined equivalent interval is used as the equivalent load amplitude. The maximum test frequency of the shaking table under the corresponding degree of freedom is selected as the test input frequency. The test duration of the equivalent interval under the corresponding degree of freedom is obtained by dividing the number of test cycles corresponding to the equivalent interval by the load frequency (i.e., the test input frequency). Then, the product of the test duration of the equivalent interval and the equivalent magnification factor is obtained to get the test duration under this degree of freedom. The damage effect of the vibration test based on the equivalent load amplitude and the test duration can be equivalent to the cumulative effect of the three intervals.

[0125] In some exemplary embodiments, before adjusting the amplitude of the original load determined based on the displacement power spectrum under each degree of freedom by the amplitude adjustment factor under the corresponding degree of freedom to obtain the test load amplitude under the corresponding degree of freedom in step S130, it further includes:

[0126] Based on the displacement power spectrum of the key components in the marine equipment under each degree of freedom and the natural frequency of the corresponding degree of freedom, determine the dynamic amplification factor of the wave load under the corresponding degree of freedom;

[0127] Based on the maximum test frequency of the shaking table under each degree of freedom and the natural frequency of the key components in the marine equipment under the corresponding degree of freedom, determine the dynamic amplification factor of the test load of the shaking table under the corresponding degree of freedom;

[0128] Based on the ratio of the dynamic amplification factor of the test load of the shaking table under each degree of freedom to the dynamic amplification factor of the wave load under the corresponding degree of freedom, determine the amplitude adjustment factor under the corresponding degree of freedom.

[0129] In the present exemplary embodiment, since the wave load is a low-frequency load and the load applied by the shaking table is a high-frequency load, the dynamic amplification factors of the two are different. Therefore, it is necessary to calculate the ratios of different load frequencies to the natural frequency of the key components in the marine equipment and the ratio of the test input frequency to the natural frequency of the key components in the marine equipment respectively, and then obtain the amplitude adjustment factor of the shaking table test of the key components in the marine equipment. The calculation formula of the dynamic amplification factor is as follows:

[0130]

[0131] In the formula, R d is the dynamic amplification factor, u o represents the structural dynamic response, (u st ) o represents the structural static response, ω is the load frequency, ω nLet ω be the natural frequency of the structure and ζ be the damping ratio of the structure. The dynamic magnification factors corresponding to the original load frequency and the test load frequency are calculated respectively through Equation (7), and the ratio of the two dynamic magnification factors is the amplitude adjustment coefficient. Substitute the peak frequency of the displacement power spectrum and the natural frequency of the key components into Equation (7) to obtain the dynamic magnification factor R of the wave load. d1 Substitute the test frequency and the natural frequency of the key components into Equation (7) to obtain the dynamic magnification factor R of the test load. d2 Then the amplitude adjustment coefficient is R d2 ÷R d1 . Accordingly, divide the original load amplitude by the amplitude adjustment coefficient to obtain the adjusted load amplitude (i.e., the test load amplitude). Among them, the root mean square value obtained by integrating and then taking the square root of the displacement power spectrum is used as the original load amplitude. This example can compensate for the difference between high-frequency loads and low-frequency loads and improve the accuracy of the test structure; by amplifying the load amplitude, the test duration is shortened and the test efficiency is improved.

[0132] In some exemplary embodiments, after adjusting the amplitude of the equivalent test load based on the amplitude adjustment coefficient for each degree of freedom in step S130 to obtain the test load amplitude corresponding to the degree of freedom, it further includes:

[0133] For each degree of freedom, if the corresponding test load amplitude is less than the swing amplitude limit of the shaking table, calculate the ratio of the swing amplitude limit of the shaking table to the corresponding test load amplitude as the original magnification factor;

[0134] Based on the loss equivalence principle, determine the scaling correspondence relationship between the load amplitude and the test duration of the key components in the marine equipment;

[0135] Based on the original magnification factor and the scaling correspondence relationship between the load amplitude and the test duration of the key components in the marine equipment, adjust the test duration for the corresponding degree of freedom to obtain the adjusted test duration for the corresponding degree of freedom;

[0136] The shaking table vibration test of the key components in the marine equipment based on the test load amplitude, test duration, and maximum test frequency of the shaking table for each degree of freedom includes:

[0137] Conduct a shaking table vibration test of the key components in the marine equipment based on the swing amplitude limit of the shaking table, the adjusted test duration, and the maximum test frequency of the shaking table for each degree of freedom.

[0138] In this exemplary embodiment, if the test load amplitude does not reach the equipment capacity of the shaking table, that is, the test load amplitude is less than the swing amplitude limit of the shaking table, in order to further shorten the test duration, the test load amplitude can be adjusted to the swing amplitude limit of the shaking table, and the ratio of the swing amplitude limit of the shaking table to the corresponding test load amplitude is used as the original amplification factor. The scaling correspondence between the load amplitude and the test duration of the key components in the marine equipment is determined by using the loss equivalence principle. The specific correspondence is as follows:

[0139]

[0140] In the formula, T b is the test duration before scaling, T b′ is the test duration after scaling, A b is the load amplitude before scaling, A b′ is the load amplitude after scaling. For example, when the material constant k = 2, if the original amplification factor is 2, the test duration is reduced to 1 / 4 of the original. Then, based on the swing amplitude limit of the shaking table under each degree of freedom, the adjusted test duration, and the maximum test frequency of the shaking table under the corresponding degree of freedom, the shaking table vibration test of the key components in the marine equipment can be carried out. On the basis of exhausting the equipment capacity of the shaking table, the test duration can be shortened as much as possible, and the test efficiency can be improved.

[0141] In the present invention, the vibration test parameters corresponding to each degree of freedom are calculated separately for the six degrees of freedom. If the six degrees of freedom are input simultaneously for the test, the shaking table test machine will be overloaded. Then, the single-degree-of-freedom test can be carried out, that is, the six degrees of freedom of surge, sway, heave, roll, pitch, and yaw are tested separately. The test input adopts the maximum capacity limit provided by the single degree of freedom of the shaking table, and the test duration of each degree of freedom is adjusted proportionally based on the original test duration.

[0142] Experimental verification

[0143] Taking the top valve module of the converter valve as an example for illustration, according to the above steps, the bottom displacement power spectrum of the top valve module under the heave degree of freedom can be obtained as Figure 2 shown. Extract the frequency corresponding to the peak value of this power spectrum. The peak position of this power spectrum is at a frequency X of 0.1039 Hz, and the displacement power spectrum Y is 45.58 m 2 / Hz; The actual vibration times (i.e., the total number of cycles) of the load in this degree of freedom can be approximately obtained from the frequency at this position and the actual transportation time of the converter valve. Also, based on the three-interval method of Gaussian distribution proposed by Steinberg, and using Miner's law for fatigue calculation, when one standard deviation is used as the load amplitude, the assumed test cycle number is 0.6831 * total cycle number; when two standard deviations are used as the load amplitude, the assumed test cycle number is 0.271 * total cycle number; when three standard deviations are used as the load amplitude, the assumed test cycle number is 0.0433 * total cycle number. The cycle action times under each standard deviation as the load amplitude can be obtained respectively. Considering the peak frequency of the load spectrum and the maximum frequency that the shaking table can provide, the test frequencies for each degree of freedom are determined. In this example, to shorten the test duration, the maximum frequency that the shaking table can provide is selected as the test frequency. According to the cycle action times corresponding to the selected load amplitude and the test frequency, the test duration in the heave degree of freedom can be obtained, and the calculation method for the test duration of other degrees of freedom is the same.

[0144] Taking the peak frequency of the heave displacement power spectrum as the load frequency, the root mean square value is obtained by integrating the power spectrum and then taking the square root. This root mean square value is used as the test load amplitude. However, since the original load is a low-frequency load and the load applied by the shaking table is a high-frequency load, the amplification factors are different. Therefore, amplitude adjustment is required according to the amplitude adjustment factor. So, before the test, a finite element modal analysis of the valve module needs to be carried out first to obtain the structural natural vibration frequency. The finite element model of the converter valve is as Figure 3 shown, and the finite element model of the top valve module is as Figure 4 shown. Substituting the heave degree of freedom frequency and the structural natural vibration frequency into the formula, the amplification factor R d1 of the original load can be obtained. Then, substituting the test frequency and the structural natural vibration frequency, the amplification factor R d2 of the test load is obtained. The amplitude adjustment factor is R d2 ÷R d1 . Dividing the original load amplitude by the adjustment factor can obtain the adjusted amplitude.

[0145] From the damage equivalence relation, it can be obtained that doubling the test duration of the two-fold variance is equivalent to the sum of the damages of the one-fold, two-fold, and three-fold variances, that is, the test is carried out according to the two-fold variance. And when the load amplitude is doubled (while meeting the requirements of the shaking table capacity limit), the test duration is reduced by four times, thereby shortening the test duration. Finally, the test load amplitudes and test durations for each degree of freedom can be obtained. If the six degrees of freedom are input for the test simultaneously and the shaking table testing machine is overloaded, then the six degrees of freedom are tested separately in sequence. At this time, according to the response equivalence principle, the load in a single degree of freedom is amplified, and the amplification factor is selected based on the linear relationship between the load and the response, so that the structural response in a single degree of freedom is consistent with the structural response under the combined action of the six degrees of freedom. After that, the process of obtaining the test input data is the same as the above process.

[0146] The sea transportation simulation analysis of the flexible DC converter valve can be completed by finite element analysis software according to environmental parameters and structural parameters, but there is a lack of test data for verification, so the credibility of the sea transportation simulation analysis results is in doubt. At present, due to reasons such as limited specifications of vibration tables or shaking tables, there is no real test data for the flexible DC converter valve to be used for closed-loop verification of the seismic (vibration) simulation analysis results for each time. Therefore, in view of the current data blank in this field, the present invention proposes a shaking table vibration test method based on the principle of damage equivalence. The test input data includes three parts: test duration, input frequency, and load input (amplitude). For the input frequency: initially select the maximum frequency that the test equipment can provide as the input frequency. For the test duration: based on the peak frequency of the load power spectrum and the actual transportation time, approximately obtain the actual number of cycles, and then obtain the test duration from the maximum frequency of the vibration table (shaking table). For the load input: calculate the ratio of the load frequency to the natural frequency of the structure, and then obtain the adjustment coefficient of the test load amplitude, and then adjust the amplitude to obtain the load input. The test results can be used as the real test data of the flexible DC converter valve for closed-loop verification or evaluation of the seismic (vibration) simulation analysis results for each time; at the same time, it can overcome current problems including limited equipment specifications and provide test data support for the sea transportation of the converter valve. In addition, for the fatigue numerical values of the component connection parts, the current specifications lack relevant mechanical standards and cannot be verified numerically, so the test method provided by the present invention can provide test verification for it. Finally, by comparing the test results in the present invention with the simulation results, it can also be used for parameter update of the finite element model, laying a foundation for improving the accuracy of subsequent numerical simulations.

[0147] Example 2

[0148] Based on the same inventive concept, the present invention also provides a method for checking the strength of key components of a sea transportation device, including:

[0149] Obtain the test results of the shaking table vibration test of the key components in the sea transportation device described in any one of Embodiment 1;

[0150] Perform corresponding strength checks based on the test results of the shaking table vibration test of the key components in the sea transportation device and the strength requirements of the key components in the sea transportation device.

[0151] In the present exemplary embodiment, the test results may include vibration response curves. The strength check is performed by comparing the response amplitudes in the vibration response curves with the corresponding structural strengths. If the response amplitude is less than the structural strength, the strength check passes, indicating that the strength of the key components in the sea transportation device meets the requirements.

[0152] Exemplarily, the sea transportation device is a flexible DC converter valve, and the key component is the top valve module of the flexible DC converter valve. As Figure 5As shown in the figure, the left part of the figure is a schematic diagram of the valve tower structure of the converter valve, and the right part is a schematic diagram of the top valve module structure of the valve tower. Its position in the valve tower is marked as shown in the circle. The flexible DC converter valve is one of the key components in the flexible DC transmission system and is a bridge for the mutual conversion between DC transmission and AC transmission. The power modules placed in the tower body of the converter valve tower have high technical content and high cost. Therefore, its strength needs to be ensured during its sea transportation. During sea transportation, the converter valve is mainly affected by wave loads. Through the transmission of wave loads by the lower structure, the top valve module of the converter valve is subjected to large vibration impacts, and the displacement of the top valve module of the converter valve is large, and it is easy to cause damage inside the top valve module. Therefore, in this example, the top valve module of the converter valve tower, which is subjected to large vibration impacts and large displacements, is selected as the test sub-structure. By selecting the test object as the top structure of the equipment, in this way, only the bottom load needs to be obtained, and the relationship with the overall structure does not need to be further processed to actually reflect the real situation. Moreover, based on the damage equivalence relationship, the test duration is greatly shortened, and the design process is convenient and fast; the test can directly reflect the structural safety of the valve tower top module during sea transportation, check the strength, and the test results can be used to update the finite element model of the valve tower, laying a foundation for improving the accuracy of numerical simulation.

[0153] In view of the current situation that there is a blank in the test data of the flexible DC converter valve during sea transportation, this example provides a test design method for the converter valve module. The top module of the valve tower, which is subjected to large vibration impacts and large displacements, is selected as the test sub-structure. Based on the damage equivalence principle and the capacity limit of the shaking table, the test parameters are determined, and a physical test is carried out. The test results can directly reflect the structural safety of the valve tower top module during sea transportation and check the strength. By simulating the wave loads during the sea transportation of the converter valve and checking whether the strength of its valve module meets the requirements for strength checking, damage to the internal structure of the converter valve can be prevented, and the state of the valve body during sea transportation can be accurately simulated in advance through the test to avoid damage to the valve body and economic losses.

[0154] Example 3

[0155] Based on the same inventive concept, the present invention also provides a shaking table vibration test system for key components of a sea transportation device, and the system includes:

[0156] A cycle number determination module, configured to determine the actual number of cyclic actions in each degree of freedom based on the peak frequency of the displacement power spectrum and the actual sea transportation time of the key component in the sea transportation device in each degree of freedom;

[0157] An equivalent conversion module, configured to determine the damage equivalence relationship in each degree of freedom based on the displacement power spectrum and the actual number of cyclic actions in each degree of freedom, and determine the equivalent test load and test duration in the corresponding degree of freedom based on the damage equivalence relationship in each degree of freedom;

[0158] An amplitude adjustment module, configured to adjust the amplitude of the equivalent test load based on the amplitude adjustment coefficient for each degree of freedom to obtain the test load amplitude corresponding to each degree of freedom;

[0159] A vibration test module, configured to perform a shaking table vibration test on key components in a marine device based on the test load amplitude, test duration, and maximum test frequency of the shaking table at each degree of freedom;

[0160] Wherein, the amplitude adjustment coefficient is determined based on the difference between the dynamic amplification coefficient of the wave load and the dynamic amplification coefficient of the shaking table test load.

[0161] In a possible implementation manner, it further includes a simulation analysis module, and the simulation analysis module is configured to:

[0162] Based on a simulation analysis of the transport ship of the marine device, obtain a ship amplitude response operator, and calculate the motion power spectrum of the ship's center of gravity based on the wave spectrum of the navigation sea area and the ship amplitude response operator;

[0163] Using the motion power spectrum of the ship's center of gravity as an input, perform a simulation analysis on the finite element model of the load-bearing mechanism of the marine device to obtain the root displacement power spectrum of the marine device;

[0164] Using the root displacement power spectrum of the marine device as an input, perform a simulation analysis on the finite element model of the marine device to obtain the displacement power spectrum of key components in the marine device at each degree of freedom.

[0165] In a possible implementation manner, the equivalent conversion module includes:

[0166] A sub-module for calculating by intervals, configured to calculate the load amplitude and test cycle action times corresponding to each interval at each degree of freedom by using the three-interval method based on the displacement power spectrum at each degree of freedom and the actual cycle action times at each degree of freedom; determine the fatigue life corresponding to each interval at each degree of freedom based on the load amplitude corresponding to each interval at each degree of freedom and the S-N curve relationship of key components in the marine device;

[0167] An equivalent calculation sub-module, configured to determine the equivalent interval and equivalent magnification corresponding to each degree of freedom by using Miner's law and the fatigue damage equivalence principle based on the test cycle action times and fatigue life corresponding to each interval at each degree of freedom, so that the fatigue damage of the load amplitude corresponding to the equivalent interval under the test duration corresponding to the equivalent magnification is equivalent to the sum of the fatigue damages of the load amplitudes corresponding to each interval, thereby obtaining the damage equivalence relationship corresponding to each degree of freedom.

[0168] Wherein, the equivalent interval belongs to the three intervals corresponding to the three-interval method.

[0169] In a possible implementation manner, the load amplitudes corresponding to each interval under each degree of freedom include the load amplitude corresponding to one standard deviation of the displacement power spectrum under each degree of freedom, the load amplitude corresponding to two standard deviations of the displacement power spectrum under each degree of freedom, and the load amplitude corresponding to three standard deviations of the displacement power spectrum under each degree of freedom.

[0170] In a possible implementation manner, the damage equivalence relationship is as follows:

[0171]

[0172] Where D is the sum of the fatigue damages corresponding to the load amplitudes of each interval, n 1σ 、n 2σ 、n 3σ are respectively the number of test cycle actions under the load amplitudes corresponding to one standard deviation, two standard deviations, and three standard deviations; N 1σ 、N 2σ 、N 3σ are respectively the fatigue lives under the load amplitudes corresponding to one standard deviation, two standard deviations, and three standard deviations; a is the equivalent magnification factor, n xσ 、N xσ are respectively the number of test cycle actions and the fatigue life under the load amplitude corresponding to the equivalent interval; K is the load response relationship coefficient of the key component in the marine equipment, C and k are respectively material constants, and A1, A2, and A3 are respectively the load amplitudes corresponding to one standard deviation, two standard deviations, and three standard deviations.

[0173] In a possible implementation manner, the equivalent conversion module further includes an equivalent conversion sub-module, and the equivalent conversion sub-module is used for:

[0174] Taking the load amplitude corresponding to the equivalent interval under each degree of freedom as the equivalent load amplitude under the corresponding degree of freedom;

[0175] Based on the number of test cycle actions corresponding to the equivalent interval in the damage equivalence relationship under each degree of freedom and the maximum test frequency of the shaking table under the corresponding degree of freedom, determining the test duration of the equivalent interval under the corresponding degree of freedom;

[0176] Based on the product of the test duration of the equivalent interval under each degree of freedom and the equivalent magnification factor, determining the test duration under the corresponding degree of freedom.

[0177] In a possible implementation manner, the amplitude adjustment module includes:

[0178] A wave amplification factor determination sub-module, which is used to determine the dynamic amplification factor of the wave load under the corresponding degree of freedom based on the displacement power spectrum of the key component in the marine equipment under each degree of freedom and the natural frequency of the corresponding degree of freedom;

[0179] The test magnification factor determination sub-module is used to determine the dynamic magnification factor of the test load of the shaking table under the corresponding degree of freedom based on the maximum test frequency under each degree of freedom of the shaking table and the natural frequency under the corresponding degree of freedom of the key components in the marine equipment;

[0180] The adjustment factor determination sub-module is used to determine the amplitude adjustment factor under the corresponding degree of freedom based on the ratio of the dynamic magnification factor of the test load of the shaking table under each degree of freedom to the dynamic magnification factor of the wave load under the corresponding degree of freedom.

[0181] In a possible implementation manner, it further includes a parameter scaling module, and the parameter scaling module includes:

[0182] The original coefficient calculation sub-module is used to, for each degree of freedom, if the corresponding test load amplitude is less than the swing amplitude limit of the shaking table, calculate the ratio of the swing amplitude limit of the shaking table to the corresponding test load amplitude as the original magnification factor;

[0183] The corresponding relationship determination sub-module is used to determine the scaling corresponding relationship between the load amplitude and the test duration of the key components in the marine equipment based on the loss equivalence principle;

[0184] The duration adjustment sub-module is used to adjust the test duration under the corresponding degree of freedom based on the original magnification factor and the scaling corresponding relationship between the load amplitude and the test duration of the key components in the marine equipment to obtain the adjusted test duration under the corresponding degree of freedom;

[0185] The vibration test module is specifically used for:

[0186] Performing a shaking table vibration test on the key components in the marine equipment based on the swing amplitude limit of the shaking table, the adjusted test duration, and the maximum test frequency of the shaking table under each degree of freedom.

[0187] Embodiment 4

[0188] Based on the same inventive concept, the present invention also provides a strength checking system for key components of marine equipment, including:

[0189] The result acquisition module is used to acquire the test results of the shaking table vibration test of the key components in the marine equipment described in any one of the embodiments;

[0190] The strength checking module is used to perform corresponding strength checking based on the test results of the shaking table vibration test of the key components in the marine equipment and the strength requirements of the key components in the marine equipment.

[0191] In a possible implementation manner, the marine equipment is a flexible DC converter valve; the key component is the top valve module of the flexible DC converter valve.

[0192] Example 5

[0193] As Figure 6 shown, the present invention also provides an electronic device, which may be a computer device, a single-chip microcomputer device, a smart mobile device, etc. The electronic device in this embodiment may include a processor, a memory, a transceiver component, etc. The memory, the processor, and the transceiver component are connected through a bus; the memory can be used to store an execution program, and an exemplary execution program may include instructions; the processor is used to execute the instructions stored in the memory. The memory can also be used to store data, and the data can be called and / or modified when the instructions are executed.

[0194] The processor may be a Central Processing Unit (CPU), or may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, and is suitable for implementing one or more instructions. Specifically, it is suitable for loading and executing one or more instructions in the storage medium to implement the corresponding method flow or corresponding function, so as to implement the steps of a method for shaking table vibration test of key components of a marine device and / or a method for strength verification of key components of a marine device in the above embodiments.

[0195] Example 6

[0196] Based on the same inventive concept, the present invention also provides a readable storage medium, specifically an electronic device-readable storage medium (Memory). The electronic device-readable storage medium is a memory device in the electronic device, used to store programs and data. It can be understood that the storage medium here can include both the built-in storage medium in the electronic device and, of course, the extended storage medium supported by the electronic device. The storage medium provides a storage space, and this storage space stores the operating system of the terminal. And, in this storage space, there are also stored one or more instructions suitable for being loaded and executed by the processor. These instructions can be one or more execution programs (including program codes). It should be noted that the storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. By the processor loading and executing one or more instructions stored in the storage medium, the steps of a method for the vibration test of a key component of a marine equipment swing table and / or a method for the strength check of a key component of a marine equipment in the above embodiments can be implemented.

[0197] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program codes.

[0198] The present invention is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the specified functions in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0199] These computer program instructions can also be stored in a computer-readable memory that can direct the computer or other programmable data processing devices to work in a specific manner, such that the instructions stored in this computer-readable memory generate a manufactured article including an instruction device, and this instruction device implements the specified functions in Figure 1 one flow or multiple flows and / or blocks Figure 1The functions specified in one or more boxes.

[0200] These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable device provide for implementing the steps of the functions specified in Figure 1 one process or more processes and / or boxes Figure 1 the functions specified in one box or more boxes.

[0201] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the scope of its protection. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that after reading the present invention, various changes, modifications or equivalent replacements can still be made to the specific implementation manners of the application. However, these changes, modifications or equivalent replacements are all within the scope of the protection of the claims pending for approval of the application.

Claims

1. A vibration test method for a swing table, which is a key component of a marine equipment, characterized in that, Including: Determining the actual number of cyclic actions for each degree of freedom based on the peak frequency of the displacement power spectrum of the key components in the marine equipment at each degree of freedom and the actual marine operation time; Determining the damage equivalence relationship for each degree of freedom based on the displacement power spectrum and the actual number of cyclic actions for each degree of freedom, and determining the equivalent test load and test duration for the corresponding degree of freedom based on the damage equivalence relationship for each degree of freedom; Adjusting the amplitude of the equivalent test load based on the amplitude adjustment factor for each degree of freedom to obtain the test load amplitude for the corresponding degree of freedom; Performing a shaking table vibration test on the key components in the marine equipment based on the test load amplitude, test duration, and the maximum test frequency of the shaking table at each degree of freedom; Wherein, the amplitude adjustment factor is determined based on the difference between the dynamic amplification factor of the wave load and the dynamic amplification factor of the shaking table test load.

2. The method according to claim 1, wherein Before determining the actual number of cyclic actions for each degree of freedom based on the peak frequency of the displacement power spectrum of the key components in the marine equipment at each degree of freedom and the actual marine operation time, it further includes: Performing a simulation analysis on the transport ship of the marine equipment to obtain the ship amplitude response operator, and calculating the motion power spectrum of the ship's center of gravity based on the wave spectrum of the navigation sea area and the ship amplitude response operator; Performing a simulation analysis on the finite element model of the load-bearing mechanism of the marine equipment with the motion power spectrum of the ship's center of gravity as the input to obtain the root displacement power spectrum of the marine equipment; Performing a simulation analysis on the finite element model of the marine equipment with the root displacement power spectrum of the marine equipment as the input to obtain the displacement power spectrum of the key components in the marine equipment at each degree of freedom.

3. The method according to claim 1, wherein Determining the damage equivalence relationship for each degree of freedom based on the displacement power spectrum and the actual number of cyclic actions for each degree of freedom, including: Calculating the load amplitude and the number of test cyclic actions corresponding to each interval for each degree of freedom by using the three-interval method based on the displacement power spectrum and the actual number of cyclic actions for each degree of freedom; Determining the fatigue life corresponding to each interval for each degree of freedom based on the load amplitude corresponding to each interval for each degree of freedom and the S-N curve relationship of the key components in the marine equipment; Determining the equivalent interval and equivalent multiple for the corresponding degree of freedom by using Miner's law and the fatigue damage equivalence principle based on the number of test cyclic actions and fatigue life corresponding to each interval for each degree of freedom, so that the fatigue damage of the load amplitude corresponding to the equivalent interval under the test duration corresponding to the equivalent multiple is equivalent to the sum of the fatigue damages of the load amplitudes corresponding to each interval, thereby obtaining the damage equivalence relationship for the corresponding degree of freedom; Wherein, the equivalent interval belongs to the three intervals corresponding to the three-interval method.

4. The method according to claim 3, wherein The load amplitude corresponding to each interval for each degree of freedom includes the load amplitude corresponding to one standard deviation of the displacement power spectrum for each degree of freedom, the load amplitude corresponding to two standard deviations of the displacement power spectrum for each degree of freedom, and the load amplitude corresponding to three standard deviations of the displacement power spectrum for each degree of freedom.

5. The method according to claim 4, wherein The damage equivalence relationship is as follows: Among them, D is the sum of fatigue damages corresponding to the load amplitudes in each interval, n 1σ , n 2σ , n 3σ are the number of test cycle actions corresponding to the load amplitudes at one standard deviation, two standard deviations, and three standard deviations respectively; N 1σ , N 2σ , N 3σ are the fatigue lives corresponding to the load amplitudes at one standard deviation, two standard deviations, and three standard deviations respectively; a is the equivalent magnification factor, n xσ , N xσ are the number of test cycle actions and fatigue life corresponding to the load amplitude in the equivalent interval respectively; K is the load response relationship coefficient of the key components in the marine equipment, C and k are material constants respectively, and A1, A2, and A3 are the load amplitudes corresponding to one standard deviation, two standard deviations, and three standard deviations respectively.

6. The method according to claim 3, characterized in that, Determining the equivalent test load and test duration corresponding to each degree of freedom based on the damage equivalence relationship for each degree of freedom includes: Taking the load amplitude corresponding to the equivalent interval for each degree of freedom as the equivalent load amplitude for the corresponding degree of freedom; Based on the number of test cycle actions corresponding to the equivalent interval in the damage equivalence relationship for each degree of freedom and the maximum test frequency of the shaking table in the corresponding degree of freedom, determining the test duration of the equivalent interval for the corresponding degree of freedom; Based on the product of the test duration of the equivalent interval for each degree of freedom and the equivalent magnification factor, determining the test duration for the corresponding degree of freedom.

7. The method according to claim 1, wherein Before adjusting the amplitude of the original load determined based on the displacement power spectrum for each degree of freedom by the amplitude adjustment factor for each degree of freedom to obtain the test load amplitude for the corresponding degree of freedom, it further includes: Based on the displacement power spectrum of the key components in the marine equipment for each degree of freedom and the natural frequency of the corresponding degree of freedom, determining the dynamic amplification factor of the wave load for the corresponding degree of freedom; Based on the maximum test frequency of the shaking table for each degree of freedom and the natural frequency of the key components in the marine equipment for the corresponding degree of freedom, determining the dynamic amplification factor of the test load of the shaking table for the corresponding degree of freedom; Based on the ratio of the dynamic amplification factor of the test load of the shaking table for each degree of freedom to the dynamic amplification factor of the wave load for the corresponding degree of freedom, determining the amplitude adjustment factor for the corresponding degree of freedom.

8. The method according to any one of claims 1-7, characterized in that, After adjusting the amplitude of the equivalent test load by the amplitude adjustment factor for each degree of freedom to obtain the test load amplitude for the corresponding degree of freedom, it further includes: For each degree of freedom, if the corresponding test load amplitude is less than the swing amplitude limit of the shaking table, calculating the ratio of the swing amplitude limit of the shaking table to the corresponding test load amplitude as the original amplification factor; Determining the scaling correspondence relationship between the load amplitude and test duration of the key components in the marine equipment based on the loss equivalence principle; Based on the original amplification factor and the scaling correspondence relationship between the load amplitude and test duration of the key components in the marine equipment, adjusting the test duration for the corresponding degree of freedom to obtain the adjusted test duration for the corresponding degree of freedom; The shaking table vibration test of the key components in the marine equipment based on the test load amplitude, test duration, and the maximum test frequency of the shaking table for each degree of freedom includes: Conducting the shaking table vibration test of the key components in the marine equipment based on the swing amplitude limit of the shaking table, the adjusted test duration, and the maximum test frequency of the shaking table for each degree of freedom.

9. A method for strength verification of key components of a marine equipment, characterized in that, It includes: Obtaining the test results of the shaking table vibration test of the key components in the marine equipment according to any one of claims 1-8; Based on the test results of the shaking table vibration test of the key components in the marine equipment and the strength requirements of the key components in the marine equipment, conducting corresponding strength checks.

10. The method according to claim 9, wherein The marine equipment is a flexible DC converter valve; the key component is the top valve module of the flexible DC converter valve.

11. A swing table vibration test system for key components of a marine equipment, characterized in that, It includes: A cycle number determination module, configured to determine the actual number of cycle actions for each degree of freedom based on the peak frequency of the displacement power spectrum of the key components in the marine equipment for each degree of freedom and the actual marine operation time; An equivalent conversion module is used to determine the damage equivalent relationship for each degree of freedom based on the displacement power spectrum and the actual number of cyclic actions under each degree of freedom, and determine the equivalent test load and test duration under the corresponding degree of freedom based on the damage equivalent relationship for each degree of freedom; An amplitude adjustment module is used to adjust the amplitude of the equivalent test load based on the amplitude adjustment coefficient under each degree of freedom to obtain the test load amplitude under the corresponding degree of freedom; A vibration test module is used to perform a shaking table vibration test on key components in a marine device based on the test load amplitude, test duration, and the maximum test frequency of the shaking table under each degree of freedom; Wherein, the amplitude adjustment coefficient is determined based on the difference between the dynamic amplification coefficient of the wave load and the dynamic amplification coefficient of the shaking table test load.

12. The system according to claim 11, wherein It further includes a simulation analysis module, and the simulation analysis module is used for: Based on the simulation analysis of the transport ship of the marine device, obtaining the ship amplitude response operator, and calculating the motion power spectrum of the ship's center of gravity based on the wave spectrum of the navigation sea area and the ship amplitude response operator; Using the motion power spectrum of the ship's center of gravity as the input, performing a simulation analysis on the finite element model of the bearing mechanism of the marine device to obtain the root displacement power spectrum of the marine device; Using the root displacement power spectrum of the marine device as the input, performing a simulation analysis on the finite element model of the marine device to obtain the displacement power spectrum of key components in the marine device under each degree of freedom.

13. The system according to claim 11, wherein The equivalent conversion module includes: A sub-module for calculating in intervals is used to calculate the load amplitude and the number of test cyclic actions corresponding to each interval under each degree of freedom by using the three-interval method based on the displacement power spectrum and the actual number of cyclic actions under each degree of freedom; determining the fatigue life corresponding to each interval under each degree of freedom based on the load amplitude corresponding to each interval under each degree of freedom and the S-N curve relationship of the key components in the marine device; An equivalent calculation sub-module is used to determine the equivalent interval and equivalent multiple under the corresponding degree of freedom based on the number of test cyclic actions and fatigue life corresponding to each interval under each degree of freedom by using Miner's law and the fatigue damage equivalence principle, so that the fatigue damage of the load amplitude corresponding to the equivalent interval under the test duration corresponding to the equivalent multiple is equivalent to the sum of the fatigue damages of the load amplitudes corresponding to each interval, thereby obtaining the damage equivalent relationship for the corresponding degree of freedom; Wherein, the equivalent interval belongs to the three intervals corresponding to the three-interval method.

14. The system according to claim 13, wherein The load amplitude corresponding to each interval under each degree of freedom includes the load amplitude corresponding to one standard deviation of the displacement power spectrum under each degree of freedom, the load amplitude corresponding to two standard deviations of the displacement power spectrum under each degree of freedom, and the load amplitude corresponding to three standard deviations of the displacement power spectrum under each degree of freedom.

15. The system according to claim 14, wherein The damage equivalent relationship is as follows: where D is the sum of fatigue damages corresponding to the load amplitudes in each interval, n 1σ , n 2σ , n 3σ are the number of test cycle actions corresponding to the load amplitudes of one standard deviation, two standard deviations, and three standard deviations respectively; N 1σ , N 2σ , N 3σ are the fatigue lives corresponding to the load amplitudes of one standard deviation, two standard deviations, and three standard deviations respectively; a is the equivalent magnification factor, n xσ , N xσ are the number of test cycle actions and fatigue life corresponding to the load amplitude in the equivalent interval respectively; K is the load response relationship coefficient of the key components in the marine equipment, C and k are material constants respectively, and A1, A2, and A3 are the load amplitudes corresponding to one standard deviation, two standard deviations, and three standard deviations respectively.

16. The system according to claim 13, wherein The equivalent conversion module further includes an equivalent conversion sub-module, and the equivalent conversion sub-module is used for: Taking the load amplitude corresponding to the equivalent interval under each degree of freedom as the equivalent load amplitude under the corresponding degree of freedom; Determine the test duration of the equivalent interval at the corresponding degree of freedom based on the number of test cycles corresponding to the equivalent interval in the damage equivalence relationship at each degree of freedom and the maximum test frequency of the shaking table at the corresponding degree of freedom. Determine the test duration at the corresponding degree of freedom based on the product of the test duration of the equivalent interval and the equivalent magnification factor at each degree of freedom.

17. The system according to claim 11, wherein The amplitude adjustment module includes: A wave amplification factor determination sub-module, configured to determine the dynamic amplification factor of the wave load at the corresponding degree of freedom based on the displacement power spectrum of the key components in the marine equipment at each degree of freedom and the natural frequency of the corresponding degree of freedom. A test amplification factor determination sub-module, configured to determine the dynamic amplification factor of the test load of the shaking table at the corresponding degree of freedom based on the maximum test frequency of the shaking table at each degree of freedom and the natural frequency of the key components in the marine equipment at the corresponding degree of freedom. An adjustment factor determination sub-module, configured to determine the amplitude adjustment factor at the corresponding degree of freedom based on the ratio of the dynamic amplification factor of the test load of the shaking table at each degree of freedom to the dynamic amplification factor of the wave load at the corresponding degree of freedom.

18. The system according to any one of claims 11-17, characterized in that, It further includes a parameter scaling module, and the parameter scaling module includes: An original coefficient calculation sub-module, for each degree of freedom, if the corresponding test load amplitude is less than the swing amplitude limit of the shaking table, calculate the ratio of the swing amplitude limit of the shaking table to the corresponding test load amplitude as the original amplification factor. A corresponding relationship determination sub-module, configured to determine the scaling corresponding relationship between the load amplitude and the test duration of the key components in the marine equipment based on the loss equivalence principle. A duration adjustment sub-module, configured to adjust the test duration at the corresponding degree of freedom based on the original amplification factor and the scaling corresponding relationship between the load amplitude and the test duration of the key components in the marine equipment, and obtain the adjusted test duration at the corresponding degree of freedom. The vibration test module is specifically configured to: Conduct a shaking table vibration test on the key components in the marine equipment based on the swing amplitude limit of the shaking table, the adjusted test duration, and the maximum test frequency of the shaking table at each degree of freedom.

19. A strength checking system for key components of a maritime equipment, characterized in that, It includes: A result acquisition module, configured to acquire the test results of the shaking table vibration test of the key components in the marine equipment according to any one of claims 1-8. A strength verification module, configured to perform corresponding strength verification based on the test results of the shaking table vibration test of the key components in the marine equipment and the strength requirements of the key components in the marine equipment.

20. The system according to claim 19, wherein The marine equipment is a flexible DC converter valve; the key component is the top valve module of the flexible DC converter valve.

21. An electronic device, characterized in that, It includes: At least one processor and a memory; The memory and the processor are connected by a bus; The memory is used to store one or more programs; When the one or more programs are executed by the at least one processor, the method according to any one of claims 1 to 10 is implemented.

22. A readable storage medium, characterized in that, There is an execution program stored thereon, and when the execution program is executed, the method according to any one of claims 1 to 10 is implemented.

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