Marine transportation equipment sub-component full-scale test method and system, electronic equipment and medium

Abstract

The invention provides a sea transportation equipment sub-component full-scale test method and system, electronic equipment and a medium, and is applied to the technical field of offshore wind power. The method comprises the following steps: selecting a test substructure based on simulation analysis of structural dynamic response of each part of marine equipment under the action of a wave load during marine transportation; adjusting the motion power spectrum of the test substructure by using the power spectrum adjustment coefficient; determining actual cycle action times based on the peak frequency of the corrected motion power spectrum and the actual sea transportation time; determining a damage equivalent relation, an equivalent test load and a test cycle action frequency by utilizing a fatigue damage equivalence principle and a three-interval method based on the corrected motion power spectrum and the actual cycle action frequency; based on the equivalent test load, the test cycle action times and the test load frequency, a swing table vibration full-scale test is carried out. The problem that the structural durability and safety of key parts of equipment cannot be accurately evaluated due to the fact that physical test data support cannot be provided is solved.

Description

Technical Field

[0001] The present invention relates to the field of offshore wind power technology, and in particular to a full-scale testing method and system for marine equipment sub-components, electronic equipment, and a medium. Background Art

[0002] Offshore wind power is a strategic emerging technology that deeply integrates wind power and marine engineering technologies. It is a key direction for my country to build a new energy system, achieve its "dual carbon" goals, and become a strong maritime nation. However, the electrical equipment required for offshore wind power generation must be transported by sea to its destination.

[0003] During maritime transport, equipment is primarily affected by wave loads. These loads are transmitted through the bottom structure, subjecting all equipment components to significant vibration shocks. This can particularly affect areas of stress concentration, leading to fatigue damage and internal structural damage, impacting normal operation. To prevent damage to the equipment's internal structure, marine transport simulation analysis is typically used for testing and evaluation of electrical equipment. However, due to limited specifications of vibration or rocking tables, physical test data is currently unavailable, making it difficult to accurately assess the structural durability and safety of key equipment components. Summary of the Invention

[0004] In order to overcome the above-mentioned problem of being unable to accurately evaluate the structural durability and safety of key parts of equipment due to the inability to provide physical test data support, the present invention provides a full-scale testing method and system for sub-components of marine equipment, electronic equipment, and medium.

[0005] In one aspect, the present invention provides a full-scale testing method for marine equipment subcomponents, comprising:

[0006] Based on the simulation analysis of the structural dynamic response of various parts of the marine equipment under the action of wave loads during sea transportation, the stress concentration parts of the marine equipment are selected as test substructures and the motion power spectrum of the test substructure is extracted during the simulation analysis;

[0007] adjusting the motion power spectrum of the test substructure using a power spectrum adjustment coefficient to obtain a corrected motion power spectrum; determining the actual number of cyclic actions based on a peak frequency of the corrected motion power spectrum and an actual shipping time;

[0008] Based on the corrected motion power spectrum and the actual number of cycles, the fatigue damage equivalence principle and the three-interval method are used to determine the damage equivalence relationship of the test substructure, and then the equivalent test load and the number of test cycles of the test substructure are determined;

[0009] Performing a rocking table vibration full-scale test on a marine equipment subcomponent corresponding to the test substructure based on the equivalent test load, the number of test cycles, and a preset test load frequency;

[0010] The power spectrum adjustment coefficient is determined based on the structural dynamic response of the test substructure.

[0011] Optionally, the marine equipment is a flexible DC converter valve, and the test substructure is a bottom submodule of the flexible DC converter valve.

[0012] Optionally, before adjusting the motion power spectrum of the test substructure by using the power spectrum adjustment coefficient to obtain a corrected motion power spectrum, the method further includes:

[0013] extracting a dynamic response result of a test substructure from a simulation analysis result of a structural dynamic response of the marine equipment under wave load during marine transportation as a concentrated dynamic response of the test substructure;

[0014] Using the motion power spectrum of the bottom of the test substructure as input, performing structural dynamic response simulation on the test substructure to obtain a separate dynamic response of the test substructure;

[0015] The power spectrum adjustment coefficient is determined based on the ratio of the concentrated dynamic response to the individual dynamic response of the test substructure by utilizing the linear relationship between the load and the response of the marine equipment.

[0016] Optionally, based on the corrected motion power spectrum and the actual number of cyclic actions, the fatigue damage equivalence principle and the three-interval method are used to determine the damage equivalence relationship of the test substructure, including:

[0017] Based on the corrected motion power spectrum and the actual number of cyclic actions, the load amplitude and the number of cyclic actions corresponding to each interval are calculated using a three-interval method;

[0018] Determine the fatigue life corresponding to each interval based on the load amplitude corresponding to each interval and the SN curve relationship of the test substructure;

[0019] Based on the number of cycles and fatigue life corresponding to each interval, the equivalent interval and equivalent ratio are determined 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 number of test cycles corresponding to the equivalent ratio is equivalent to the sum of the fatigue damage of the load amplitude corresponding to each interval, thereby obtaining the damage equivalence relationship;

[0020] The equivalent intervals belong to the three intervals corresponding to the three-interval method.

[0021] Optionally, the load amplitude corresponding to each interval includes the load amplitude corresponding to one times the mean square error of the corrected motion power spectrum, the load amplitude corresponding to two times the mean square error of the corrected motion power spectrum, and the load amplitude corresponding to three times the mean square error of the corrected motion power spectrum.

[0022] Optionally, the number of test cycles corresponding to each interval is 0.6831n, 0.271n and 0.0433n respectively, where n is the actual number of cycles.

[0023] Optionally, the damage equivalence relationship is as follows:

[0024]

[0025]

[0026] Where D is the sum of fatigue damage corresponding to the load amplitude in each interval, n 1σ 、n 2σ 、n 3σ N is the number of test cycles under the load amplitude corresponding to one times the mean square error, two times the mean square error, and three times the mean square error of the corrected motion power spectrum; 1σ 、N 2σ 、N 3σ are respectively the fatigue life under the load amplitude corresponding to one times the mean square error, two times the mean square error, and three times the mean square error of the corrected motion power spectrum; a is the equivalent magnification, n xσ 、N xσ are the number of test cycles and fatigue life under the corresponding load amplitude in the equivalent interval, respectively; K is the linear relationship coefficient of the load response of the test substructure, C and k are the material constants, A1, A2, and A3 are the load amplitudes corresponding to one times the mean square deviation, two times the mean square deviation, and three times the mean square deviation of the corrected motion power spectrum, respectively.

[0027] Optionally, the equivalent test load is the load corresponding to the equivalent interval, and the number of test cycles is the number of cycles corresponding to the equivalent interval.

[0028] Optionally, after determining the damage equivalence relationship of the test substructure based on the corrected motion power spectrum and the actual number of cycles, using the fatigue damage equivalence principle and the three-interval method, and then determining the equivalent test load and the number of test cycles of the test substructure, the method further includes:

[0029] Using the load adjustment coefficient to adjust the amplitude of the equivalent test load to obtain the test load amplitude;

[0030] Determining the test duration of the test substructure using the test load frequency and the number of test cycle actions;

[0031] Wherein, the load adjustment coefficient is determined based on the peak frequency of the motion power spectrum of the bottom of the test substructure and the test load frequency;

[0032] The step of performing a rocking table vibration full-scale test on a marine equipment subcomponent corresponding to the test substructure based on the equivalent test load, the number of test cycles, and a preset test load frequency includes:

[0033] A rocking table vibration full-scale test is performed on a marine equipment subcomponent corresponding to the test substructure based on the test load amplitude, the test duration and the preset test load frequency.

[0034] Optionally, before adjusting the amplitude of the equivalent test load by using the load adjustment coefficient to obtain the test load amplitude, the method further includes:

[0035] determining a dynamic amplification factor of the wave load based on a peak frequency of a motion power spectrum of the test substructure and a natural frequency of a marine equipment subcomponent corresponding to the test substructure;

[0036] Determining a dynamic amplification factor of the rocking table test load based on the test load frequency and the natural frequency of the marine equipment subcomponent corresponding to the test substructure;

[0037] The load adjustment factor is determined based on a ratio of a dynamic amplification factor of the rocking table test load to a dynamic amplification factor of the wave load.

[0038] Optionally, after determining the test duration of the test substructure using the test load frequency and the number of test cycle actions, the method further includes:

[0039] If the test load amplitude is less than the swing amplitude limit of the swing platform, the ratio of the swing amplitude limit of the swing platform to the test load amplitude is calculated as the original amplification factor;

[0040] Determine the scaling relationship between the load amplitude and the duration of the test substructure based on the damage equivalence principle;

[0041] Adjusting the test duration based on the original amplification factor and the scaling correspondence between the load amplitude and the duration of the test substructure to obtain an adjusted test duration;

[0042] The step of performing a rocking table vibration full-scale test on a marine equipment subcomponent corresponding to the test substructure based on the test load amplitude, the test duration, and a preset test load frequency includes:

[0043] A rocking table vibration full-scale test is performed on the marine equipment sub-component corresponding to the test sub-structure based on the rocking table's rocking amplitude limit, the adjusted test duration, and the test load frequency.

[0044] Optionally, the scaling relationship between the load amplitude and the duration of the test substructure is as follows:

[0045]

[0046] Where, T b T is the duration of the experiment before scaling. b′ is the duration of the trial after scaling, A b is the load amplitude before scaling, A b′ is the scaled load amplitude, and k is the material constant.

[0047] In another aspect, the present invention further provides a full-scale testing system for marine equipment subcomponents, comprising:

[0048] a substructure selection module for selecting stress concentration locations of the marine equipment as test substructures based on a simulation analysis of the structural dynamic responses of various locations of the marine equipment under wave loads during marine transportation, and extracting a motion power spectrum of the test substructure during the simulation analysis;

[0049] a power spectrum adjustment module, configured to adjust the motion power spectrum of the test substructure using a power spectrum adjustment coefficient to obtain a corrected motion power spectrum; and determine an actual number of cyclic actions based on a peak frequency of the corrected motion power spectrum and an actual shipping time;

[0050] an equivalent conversion module, configured to determine, based on the corrected motion power spectrum and the actual number of cyclic actions, a damage equivalence relationship of the test substructure using the fatigue damage equivalence principle and a three-interval method, and further determine an equivalent test load and the number of test cycles of the test substructure;

[0051] a full-scale test module, configured to perform a rocking table vibration full-scale test on a marine equipment subcomponent corresponding to the test substructure based on the equivalent test load, the number of test cycles, and a preset test load frequency;

[0052] The power spectrum adjustment coefficient is determined based on the structural dynamic response of the test substructure.

[0053] Optionally, the marine equipment is a flexible DC converter valve, and the test substructure is a bottom submodule of the flexible DC converter valve.

[0054] Optionally, the method further includes a spectral coefficient determination module, wherein the spectral coefficient determination module is configured to:

[0055] extracting a dynamic response result of a test substructure from a simulation analysis result of a structural dynamic response of the marine equipment under wave load during marine transportation as a concentrated dynamic response of the test substructure;

[0056] Using the motion power spectrum of the bottom of the test substructure as input, performing structural dynamic response simulation on the test substructure to obtain a separate dynamic response of the test substructure;

[0057] The power spectrum adjustment coefficient is determined based on the ratio of the concentrated dynamic response to the individual dynamic response of the test substructure by utilizing the linear relationship between the load and the response of the marine equipment.

[0058] Optionally, the equivalent conversion module includes:

[0059] an interval calculation submodule for calculating the load amplitude and the number of cycles corresponding to each interval using a three-interval method based on the corrected motion power spectrum and the actual number of cycles; and determining the fatigue life corresponding to each interval based on the relationship between the load amplitude corresponding to each interval and the SN curve of the test substructure;

[0060] a conversion submodule for determining an equivalent interval and an equivalent ratio based on the number of cycles and fatigue life corresponding to each interval, 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 number of test cycles corresponding to the equivalent ratio is equivalent to the sum of the fatigue damage of the load amplitudes corresponding to each interval, thereby obtaining the damage equivalence relationship;

[0061] The equivalent intervals belong to the three intervals corresponding to the three-interval method.

[0062] Optionally, the load amplitude corresponding to each interval includes the load amplitude corresponding to one times the mean square error of the corrected motion power spectrum, the load amplitude corresponding to two times the mean square error of the corrected motion power spectrum, and the load amplitude corresponding to three times the mean square error of the corrected motion power spectrum.

[0063] Optionally, the number of test cycles corresponding to each interval is 0.6831n, 0.271n and 0.0433n respectively, where n is the actual number of cycles.

[0064] Optionally, the damage equivalence relationship is as follows:

[0065]

[0066] Where D is the sum of fatigue damage corresponding to the load amplitude in each interval, n 1σ 、n 2σ 、n 3σN is the number of test cycles under the load amplitude corresponding to one times the mean square error, two times the mean square error, and three times the mean square error of the corrected motion power spectrum; 1σ 、N 2σ 、N 3σ are respectively the fatigue life under the load amplitude corresponding to one times the mean square error, two times the mean square error, and three times the mean square error of the corrected motion power spectrum; a is the equivalent magnification, n xσ 、N xσ are the number of test cycles and fatigue life under the corresponding load amplitude in the equivalent interval, respectively; K is the linear relationship coefficient of the load response of the test substructure, C and k are the material constants, A1, A2, and A3 are the load amplitudes corresponding to one times the mean square deviation, two times the mean square deviation, and three times the mean square deviation of the corrected motion power spectrum, respectively.

[0067] Optionally, the equivalent test load is the load corresponding to the equivalent interval, and the number of test cycles is the number of cycles corresponding to the equivalent interval.

[0068] Optionally, an amplitude adjustment module is further included, and the amplitude adjustment module includes:

[0069] an amplitude adjustment submodule, configured to adjust the amplitude of the equivalent test load using a load adjustment coefficient to obtain a test load amplitude;

[0070] a duration calculation submodule, configured to determine the test duration of the test substructure using the test load frequency and the number of test cycle actions;

[0071] Wherein, the load adjustment coefficient is determined based on the peak frequency of the motion power spectrum of the bottom of the test substructure and the test load frequency;

[0072] The full-scale test module is specifically used for:

[0073] A rocking table vibration full-scale test is performed on a marine equipment subcomponent corresponding to the test substructure based on the test load amplitude, the test duration and the preset test load frequency.

[0074] Optionally, the amplitude adjustment module further includes an amplitude adjustment coefficient determination submodule, and the amplitude adjustment coefficient determination submodule is configured to:

[0075] determining a dynamic amplification factor of the wave load based on a peak frequency of a motion power spectrum of the test substructure and a natural frequency of a marine equipment subcomponent corresponding to the test substructure;

[0076] Determining a dynamic amplification factor of the rocking table test load based on the test load frequency and the natural frequency of the marine equipment subcomponent corresponding to the test substructure;

[0077] The load adjustment factor is determined based on a ratio of a dynamic amplification factor of the rocking table test load to a dynamic amplification factor of the wave load.

[0078] Optionally, a parameter scaling module is further included, wherein the parameter scaling module is configured to:

[0079] If the test load amplitude is less than the swing amplitude limit of the swing platform, the ratio of the swing amplitude limit of the swing platform to the test load amplitude is calculated as the original amplification factor;

[0080] Determine the scaling relationship between the load amplitude and the duration of the test substructure based on the damage equivalence principle;

[0081] Adjusting the test duration based on the original amplification factor and the scaling correspondence between the load amplitude and the duration of the test substructure to obtain an adjusted test duration;

[0082] The full-scale test module is specifically used for:

[0083] A rocking table vibration full-scale test is performed on the marine equipment sub-component corresponding to the test sub-structure based on the rocking table's rocking amplitude limit, the adjusted test duration, and the test load frequency.

[0084] Optionally, the scaling relationship between the load amplitude and the duration of the test substructure is as follows:

[0085]

[0086] Where, T b T is the duration of the experiment before scaling. b′ is the duration of the trial after scaling, A b is the load amplitude before scaling, A b′ is the scaled load amplitude, and k is the material constant.

[0087] On the other hand, the present invention also provides an electronic device, comprising: at least one processor and a memory; the memory and the processor are connected via a bus;

[0088] The memory is used to store one or more programs;

[0089] When the one or more programs are executed by the at least one processor, any one of the above-mentioned full-scale testing methods for marine equipment sub-components is implemented.

[0090] On the other hand, the present invention also provides a readable storage medium having an execution program stored thereon, which, when executed, implements any one of the above-mentioned full-scale testing methods for sub-components of marine equipment.

[0091] Compared with the prior art, the present invention has the following beneficial effects:

[0092] The present invention provides a full-scale test method and system for marine equipment sub-components. Based on a simulation analysis of the structural dynamic response of various parts of the marine equipment under wave loads during marine transportation, a stress concentration part of the marine equipment is selected as a test substructure, and a motion power spectrum of the test substructure is extracted during the simulation analysis. The motion power spectrum of the test substructure is adjusted using a power spectrum adjustment coefficient. By using the stress concentration part as the test substructure and considering the difference in excitation response between the test substructure being inside the equipment and being a separate structure to which a load is applied, the extracted motion power spectrum is adjusted using the power spectrum adjustment coefficient. This can compensate for the difference in excitation response, so that the test results based on the test substructure and the compensated motion power spectrum can reflect the durability and safety of the entire equipment under wave loads, thereby improving the accuracy and reliability of the test results.

[0093] The present invention utilizes the fatigue damage equivalence principle and the three-interval method to determine the damage equivalence relationship of a test substructure, and further determines the equivalent test load and the number of test cycles of the test substructure; based on the equivalent test load, the number of test cycles and the preset test load frequency, a full-scale vibration test of a marine equipment subcomponent corresponding to the test substructure is performed on a rocking table; physical tests are carried out by determining test parameters based on the fatigue damage equivalence principle, and wave loads can be equivalently converted into physical test parameters, so that the structural safety of the equipment during marine transportation can be reflected through the test results, and the risk of damage to the internal structure of the marine equipment can be avoided; the finite element model of the test substructure can also be updated and the structure redesigned based on the test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0094] Figure 1 Schematic diagram of a flow chart of a full-scale testing method for marine equipment sub-components according to the present invention;

[0095] Figure 2 A schematic diagram of a finite element model of a converter valve according to an example of the present invention;

[0096] Figure 3 This is a stress distribution cloud diagram of various parts of a converter valve according to an example of the present invention;

[0097] Figure 4 This is a schematic diagram of a finite element model of a converter valve bottom submodule (test substructure) according to an example of the present invention;

[0098] Figure 5 This is a schematic diagram of an acceleration power spectrum according to an example of the present invention;

[0099] Figure 6 Schematic diagram of the structure of the electronic device of the present invention. DETAILED DESCRIPTION

[0100] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0101] Example 1

[0102] The present invention provides a full-scale test method for marine equipment sub-components, as shown in the schematic diagram Figure 1 As shown, including:

[0103] Step S110, based on a simulation analysis of the structural dynamic response of various parts of the marine equipment under wave loads during marine transportation, selecting a stress concentration part of the marine equipment as a test substructure and extracting a motion power spectrum of the test substructure during the simulation analysis;

[0104] Step S120, adjusting the motion power spectrum of the test substructure using a power spectrum adjustment coefficient to obtain a corrected motion power spectrum; determining the actual number of cyclic actions based on the peak frequency of the corrected motion power spectrum and the actual shipping time;

[0105] Step S130, based on the corrected motion power spectrum and the actual number of cycles, using the fatigue damage equivalence principle and the three-interval method to determine the damage equivalence relationship of the test substructure, and then determine the equivalent test load and the number of test cycles of the test substructure;

[0106] Step S140 : performing a rocking table vibration full-scale test on the marine equipment sub-component corresponding to the test sub-structure based on the equivalent test load, the number of test cycles and the preset test load frequency.

[0107] In this example embodiment, the marine equipment may be various large-scale electrical equipment used for marine transportation, and the test substructure may be a location where stress concentration is detected in the simulation analysis results. For example, the marine equipment is a flexible DC converter valve, and its finite element model is as follows: Figure 2 As shown, the test substructure is the bottom submodule of the flexible DC converter valve. Figure 4As shown. By establishing a finite element model of the marine equipment and selecting a frequency domain analysis method (such as power spectrum analysis), the wave load during the marine operation can be input from the bottom of the marine equipment finite element model in the form of a motion power spectrum, and the structural dynamic response of each part can be calculated by the finite element analysis software. The stress concentration part of the marine equipment can be selected as the test substructure, and the motion power spectrum of the test substructure in the marine equipment (such as the motion power spectrum of the bottom of the test substructure) can be extracted as the original power spectrum data. The motion power spectrum can be a displacement power spectrum or an acceleration power spectrum. The peak frequency of the corrected motion power spectrum can be multiplied by the actual marine operation time to determine the actual number of cycles. The present invention determines the vibration test parameters, namely the test load, test duration and test load frequency, through the above steps. The test duration can be determined by the number of test cycles and the test load frequency. The test load frequency can be selected from the frequency range of the rocking table load loading frequency that is far away from the fundamental frequency of the structure. In order to improve the test efficiency, the maximum test frequency that the rocking table can provide can be selected as the test load frequency. The actual number of cycles can be determined by multiplying the peak frequency of the corrected motion power spectrum of the test substructure by the actual marine operation time. The fatigue damage equivalence principle is an important concept in fatigue analysis. It is used to evaluate the damage accumulation of materials or structures under cyclic loading. Its core idea is to transform a 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 a three-interval method based on Gaussian distribution proposed by Steinberg. It is a commonly used fatigue life prediction method, mainly used to analyze the fatigue life of materials under different stress levels. This method assumes that the random excitation of the structure obeys Gaussian distribution, uses 1σ, 2σ and 3σ stress levels and vibration frequency, σ is the stress standard deviation, and combines the SN curve with the Miner criterion to calculate fatigue damage, thereby predicting fatigue life. The power spectrum adjustment coefficient is determined based on the structural dynamic response of the test substructure, and the structural dynamic response can be the stress response result of the test substructure. This invention utilizes the fatigue damage equivalence principle and the three-interval method to determine the damage equivalence relationship, and thus the vibration test parameters, making the design process convenient and efficient. The test results directly reflect the structural safety of the equipment during maritime transport and can be used to update the finite element model of maritime transport equipment, laying the foundation for improving the accuracy of numerical simulations. Furthermore, a power spectrum adjustment coefficient can be used to compensate for stress concentration in the test substructure within the overall equipment, further improving the accuracy of the test results and filling the gap in test data for maritime transport equipment (such as flexible DC converter valves).The substructure full-scale test design method based on the fatigue damage equivalence principle of the present invention can overcome current problems such as the limitations of the swing table size and loading capacity, and provide a test basis for fatigue analysis of equipment during sea transportation; it also provides test verification for the fatigue strength calculation of components in key parts of the equipment. The test results can be used to update the finite element model of the test object and redesign the structure.

[0108] In some example embodiments, the wave load during sea transportation is obtained by the following steps: based on a simulation analysis of a transport ship of the sea transportation equipment, a ship amplitude response operator is obtained, and based on the wave spectrum of the navigation area and the ship amplitude response operator, a motion power spectrum of the ship's center of gravity is calculated; using the motion power spectrum of the ship's center of gravity as input, a finite element model of the support mechanism of the sea transportation equipment is simulated and analyzed to obtain a root motion power spectrum of the sea transportation equipment; and the root motion power spectrum of the sea transportation equipment is input into the finite element model of the sea transportation equipment as the wave load during sea transportation.

[0109] In some example embodiments, before adjusting the motion power spectrum of the test substructure using the power spectrum adjustment coefficient to obtain a corrected motion power spectrum in step S120, the method further includes:

[0110] extracting a dynamic response result of a test substructure from a simulation analysis result of a structural dynamic response of the marine equipment under wave load during marine transportation as a concentrated dynamic response of the test substructure;

[0111] Using the motion power spectrum of the test substructure as input, performing structural dynamic response simulation on the test substructure to obtain a separate dynamic response of the test substructure;

[0112] The power spectrum adjustment coefficient is determined based on the ratio of the concentrated dynamic response to the individual dynamic response of the test substructure by utilizing the linear relationship between the load and the response of the marine equipment.

[0113] In this exemplary embodiment, a finite element model of the marine equipment is numerically simulated under wave loads during shipping to obtain simulation analysis results of the marine equipment's structural dynamic response. From these results, the dynamic response of a test substructure is extracted as the dynamic response of the test substructure when within the marine equipment, i.e., the concentrated dynamic response of the test substructure. A structural dynamic response simulation of the test substructure is performed using the motion power spectrum of the test substructure's bottom as input, obtaining simulation results of the individual test substructure, i.e., the individual dynamic response of the test substructure. Since there is a linear relationship between load and response in a linear elastic structure, the relationship between the corresponding input loads can be determined based on the ratio of the responses corresponding to different input loads. Therefore, the ratio of the concentrated dynamic response to the individual dynamic response of the test substructure is used as the power spectrum adjustment coefficient. Alternatively, the motion power spectrum of the test substructure can be multiplied by different amplification factors. When the response of the individual test substructure is consistent with that of the corresponding portion of the overall marine equipment, the amplification factor at that time serves as the power spectrum adjustment coefficient.

[0114] In some example embodiments, step S120 of determining the damage equivalence relationship of the test substructure based on the corrected motion power spectrum and the actual number of cyclic actions using the fatigue damage equivalence principle and the three-interval method includes:

[0115] Based on the corrected motion power spectrum and the actual number of cyclic actions, the load amplitude and the number of cyclic actions corresponding to each interval are calculated using a three-interval method;

[0116] Determine the fatigue life corresponding to each interval based on the load amplitude corresponding to each interval and the SN curve relationship of the test substructure;

[0117] Based on the number of cycles and fatigue life corresponding to each interval, the equivalent interval and equivalent ratio are determined 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 number of test cycles corresponding to the equivalent ratio is equivalent to the sum of the fatigue damage of the load amplitude corresponding to each interval, thereby obtaining the damage equivalence relationship;

[0118] The equivalent intervals belong to the three intervals corresponding to the three-interval method.

[0119] In this example embodiment, the three intervals corresponding to the three-interval method include the three stress intervals (i.e., ±1σ, ±2σ, and ±3σ) into which the corrected motion power spectrum is divided. The load amplitude corresponding to each interval in the three-interval method includes the load amplitude corresponding to one times the mean square deviation of the corrected motion power spectrum (1σ stress level), the load amplitude corresponding to two times the mean square deviation of the corrected motion power spectrum (2σ stress level), and the load amplitude corresponding to three times the mean square deviation of the corrected motion power spectrum (3σ stress level). The calculation formula for the load amplitude corresponding to one times the mean square deviation of the corrected motion power spectrum is as follows:

[0120]

[0121] Where q is the load amplitude corresponding to one times the mean square error of the corrected motion power spectrum, S(ω) is the power spectral density function of the corrected motion power spectrum, and ω is the wave frequency.

[0122] Next, fatigue calculations are performed using Miner's law. When the load amplitude is one times the mean square deviation, the number of test cycles is 0.6831*total number of cycles. When the load amplitude is twice the mean square deviation, the number of test cycles is 0.271*total number of cycles. When the load amplitude is three times the mean square deviation, the number of test cycles is 0.0433*total number of cycles. In other words, the number of cycles for the 1σ, 2σ, and 3σ stress levels is 0.683n, 0.271n, and 0.0433n, respectively, where n is the actual number of cycles, i.e., the total number of cycles. Assuming a linear relationship between the stress response and the input load, the fatigue life of each interval can be calculated based on the SN curve relationship and this linear relationship, as shown below:

[0123] S k N=C (2)

[0124] S=KA (3)

[0125]

[0126] Wherein, formula (2) is the SN curve relationship, formula (3) is the linear relationship between stress response and input load, and formula (4) is the fatigue life calculation formula; S is the stress response, A is the input load, and N is the fatigue life; N 1σ 、N 2σ 、N 3σ where A1, A2, and A3 are the load amplitudes corresponding to the one, two, and three mean square deviations of the corrected motion power spectrum, respectively. K is the linear coefficient of the load response of the test substructure. C and k are material constants related to the substructure's material, stress ratio during loading, and loading method. A1, A2, and A3 are the load amplitudes corresponding to the one, two, and three mean square deviations of the corrected motion power spectrum, respectively.

[0127] Using Miner's law and the fatigue damage equivalence principle, the number of test cycles corresponding to each interval and the fatigue life of formula (4) are substituted into the following fatigue damage calculation formula (5). The damage under the equivalent interval and equivalent magnification equivalent to the sum of the fatigue damage of the load amplitude corresponding to each interval can be obtained, and the corresponding damage equivalence relationship is obtained as shown in formula (6).

[0128]

[0129] Where D is the sum of fatigue damage corresponding to the load amplitude in each interval, n 1σ 、n 2σ 、n 3σ are the number of test cycles under the load amplitude corresponding to one times the mean square error, two times the mean square error, and three times the mean square error of the corrected motion power spectrum; a is the equivalent magnification, n is the equivalent magnification, xσ 、N xσ a、n are the number of test cycles and fatigue life under the corresponding load amplitude in the equivalent interval. xσ 、N xσ Determined by formula derivation process. For example, when the material constant k = 2, a = 5.6, n xσ =n 3σ , N xσ =N 3σ That is, the total damage is equivalent to the damage under the 3σ stress amplitude. When the number of cycles under the 3σ stress amplitude is magnified by 5.6 times, the damage is approximately equivalent to the total damage (i.e., the sum of the damage corresponding to the loads of one, two, and three times the mean square deviation). The equivalent test load is the load corresponding to the equivalent interval, and the number of test cycles is the number of cycles corresponding to the equivalent interval. In this way, when conducting a vibration test, there is no need to test the loads corresponding to one, two, and three times the mean square deviation separately. Instead, it is only necessary to test the load corresponding to three times the mean square deviation to achieve the equivalent damage effect, which greatly simplifies the test process, shortens the test time, and improves the test effect.

[0130] In some example embodiments, after determining the damage equivalence relationship of the test substructure using the fatigue damage equivalence principle and the three-interval method based on the corrected motion power spectrum and the actual number of cycles in step S130, and then determining the equivalent test load and the number of test cycles for the test substructure, the method further includes:

[0131] Using the load adjustment coefficient to adjust the amplitude of the equivalent test load to obtain the test load amplitude;

[0132] Determining the test duration of the test substructure using the test load frequency and the number of test cycle actions;

[0133] Wherein, the load adjustment coefficient is determined based on the peak frequency of the motion power spectrum of the bottom of the test substructure and the test load frequency;

[0134] The step S140 of performing a rocking table vibration full-scale test on the marine equipment subcomponent corresponding to the test substructure based on the equivalent test load, the number of test cycles, and the preset test load frequency includes:

[0135] A rocking table vibration full-scale test is performed on a marine equipment subcomponent corresponding to the test substructure based on the test load amplitude, the test duration and the preset test load frequency.

[0136] In this example implementation, considering that the wave load is a low-frequency load, and the full-scale test process loads a high-frequency load, since the amplification effects corresponding to different frequency loads are different, it is necessary to compensate the amplification factor of the equivalent load. Since the load frequency changes, there are differences in the dynamic amplification factor, so it is necessary to calculate the dynamic amplification factor before and after the load frequency adjustment to obtain the load adjustment factor of the test substructure. Specifically, the load adjustment coefficient is used to adjust the amplitude of the equivalent test load to obtain the test load amplitude. Among them, the load adjustment coefficient can be determined based on the peak frequency of the motion power spectrum at the bottom of the test substructure and the test load frequency. The test duration of the test substructure is approximately determined by dividing the number of test cycles by the test load frequency. The test load amplitude, the test duration and the preset test load frequency are used as test parameters to perform a swing table vibration full-scale test on the marine equipment sub-component corresponding to the test substructure.

[0137] In some example embodiments, before adjusting the amplitude of the equivalent test load using the load adjustment coefficient to obtain the test load amplitude, the method further includes:

[0138] determining a dynamic amplification factor of the wave load based on a peak frequency of a motion power spectrum of the test substructure and a natural frequency of a marine equipment subcomponent corresponding to the test substructure;

[0139] Determining a dynamic amplification factor of the rocking table test load based on the test load frequency and the natural frequency of the marine equipment subcomponent corresponding to the test substructure;

[0140] The load adjustment factor is determined based on a ratio of a dynamic amplification factor of the rocking table test load to a dynamic amplification factor of the wave load.

[0141] In this example implementation, since wave loads are low-frequency loads and the loads applied by the rocking platform are high-frequency loads, the dynamic amplification factors of the two are different. Therefore, it is necessary to calculate the ratio of different load frequencies to the natural frequencies of the marine equipment subcomponents corresponding to the test substructures, as well as the ratio of the test input frequency to the natural frequencies of the marine equipment subcomponents corresponding to the test substructures, to derive the load adjustment factor for the rocking platform test of the marine equipment subcomponents corresponding to the test substructures. The dynamic amplification factor calculation formula is as follows:

[0142]

[0143] Where R d is the dynamic amplification factor of the structure, u o represents the structural dynamic response, (u st ) o represents the static response of the structure, ω q is the load frequency, ω n is the structural natural frequency, and ζ is the structural damping ratio. The dynamic amplification coefficients corresponding to the original load frequency (motion power spectrum of the test substructure) and the test load frequency are calculated by formula (7). The ratio of the two dynamic amplification coefficients is the load adjustment coefficient. Substituting the peak frequency of the motion power spectrum of the test substructure and the natural frequency of the marine equipment subcomponent into formula (7) yields the dynamic amplification coefficient R of the wave load. d1 Substituting the test frequency and the natural frequency of the marine equipment sub-components into formula (7) we can obtain the dynamic amplification factor R of the test load. d2 , then the load adjustment factor is R d2 ÷R d1 Accordingly, the original load amplitude is divided by the load adjustment coefficient to obtain the adjusted load amplitude (i.e., the test load amplitude). The integrated power spectrum of the test substructure's motion can be squared to obtain the mean square value as the original load amplitude. This example can compensate for the difference in amplification factors between high-frequency and low-frequency loads, improving the accuracy of the test structure. By amplifying the load amplitude, the test duration can be shortened, improving test efficiency.

[0144] In some example embodiments, after determining the test duration of the test substructure using the test load frequency and the number of test cycles, the method further includes:

[0145] If the test load amplitude is less than the swing amplitude limit of the swing platform, the ratio of the swing amplitude limit of the swing platform to the test load amplitude is calculated as the original amplification factor;

[0146] Determine the scaling relationship between the load amplitude and the duration of the test substructure based on the damage equivalence principle;

[0147] Adjusting the test duration based on the original amplification factor and the scaling correspondence between the load amplitude and the duration of the test substructure to obtain an adjusted test duration;

[0148] The step of performing a rocking table vibration full-scale test on a marine equipment subcomponent corresponding to the test substructure based on the test load amplitude, the test duration, and a preset test load frequency includes:

[0149] A rocking table vibration full-scale test is performed on the marine equipment sub-component corresponding to the test sub-structure based on the rocking table's rocking amplitude limit, the adjusted test duration, and the test load frequency.

[0150] In this example implementation, if the test load amplitude does not reach the equipment capacity of the swing platform, that is, the test load amplitude is less than the swing amplitude limit of the swing platform, in order to further shorten the test duration, the test load amplitude can be adjusted to the swing amplitude limit of the swing platform. The ratio of the swing amplitude limit of the swing platform to the corresponding test load amplitude is used as the original magnification factor. The damage equivalence principle is used to determine the scaling correspondence between the load amplitude and duration of the key components of the marine equipment. That is, assuming that the fatigue damage before and after scaling is equal, the fatigue damage calculation formula and the fatigue life calculation formula are used to derive the specific corresponding relationship as shown below:

[0151]

[0152] Where, T b T is the duration of the experiment before scaling. b′ is the duration of the trial after scaling, A b is the load amplitude before scaling, A b′ is the scaled load amplitude. For example, when the material constant k = 2, if the original magnification factor is 2, the test duration is reduced to 1 / 4 of the original value. Based on the swing table's swing amplitude limit, the adjusted test duration, and the test load frequency, a full-scale swing table vibration test of the marine equipment subcomponent corresponding to the test substructure can be performed. This can minimize test duration and improve test efficiency while fully utilizing the swing table's equipment capacity.

[0153] Experimental verification

[0154] (1) Select the test substructure and extract the load power spectrum

[0155] The finite element model of the converter valve is established according to the structural dimensions and material parameters of the flexible DC converter valve, such as Figure 2 By analyzing the dynamic response of the converter valve during sea transportation, the stress distribution cloud diagram of the converter valve is obtained, as shown in Figure 3 As shown, Figure 3 Different colors represent different stress values. From bottom to top, the stress value ranges corresponding to different colors are 0.125*109 ~0.111*10 9 , 0.111*10 9 ~0.975*10 8 , 0.975*10 8 ~0.836*10 8 , 0.836*10 8 ~0.697*10 8 、0.697*10 8 ~0.557*10 8 、0.557*10 8 ~0.418*10 8 , 0.418*10 8 ~0.279*10 8 and 0.139*10 8 ~288.362. The zero before the decimal point is omitted in the figure. For example, .125E+09 in the figure corresponds to 0.125*10 9 .from Figure 3 It can be seen that there is stress concentration in the submodule near the bottom of the converter valve. The structure where the stress of the converter valve is the largest, that is, the bottom submodule, is selected as the test substructure. The test substructure is as follows: Figure 4 As shown in FIG, the load power spectrum at the bottom of the test substructure corresponding to when the test substructure is in the converter valve is extracted as the test data basis.

[0156] (2) Stress equivalent treatment of the test substructure

[0157] Based on the stress value at the maximum stress position of the converter valve, the load power spectrum at the bottom of the test substructure is amplified based on the linear relationship between load and response. That is, the motion power spectrum of the test substructure is adjusted using the power spectrum adjustment coefficient to ensure that the stress at the maximum stress position of the converter valve is equivalent to that at the same position of the test substructure.

[0158] (3) Processing of preliminary test parameters

[0159] According to formula (1), the load amplitude corresponding to the adjusted load power spectrum obtained in step (2) is calculated. The actual number of load cycles is obtained by multiplying the peak frequency of the adjusted load power spectrum by the actual sea transportation time. Take a load power spectrum for example analysis. The load power spectrum curve is shown in the figure below. Figure 5 As shown, its peak frequency X is 0.1451Hz, and the acceleration power spectrum density Y at the peak is 0.8866 (m / s 2 ) 2 / Hz.

[0160] (4) Fatigue equivalent treatment of test substructure

[0161] The three-interval method based on Gaussian distribution can be used to calculate the number of cycles at stress amplitudes of 1σ, 2σ, and 3σ, which account for 68.31%, 27.1%, and 4.33% of the actual number of cycles, respectively. According to the fatigue damage equivalent formula (6), the total damage is equivalent to the damage at a stress amplitude of 3σ. When the number of cycles at a stress amplitude of 3σ is magnified by 5.6 times, the damage is approximately equivalent to the total damage. At this time, the material constant k in the SN curve is set to 2. If k takes other values, it can be adjusted according to the above method.

[0162] (5) Adjust the test excitation parameters based on the swing table limit

[0163] First, the load frequency is adjusted according to the load frequency range of the swing table to determine the loading time. Considering the different amplification effects at different frequencies, the dynamic amplification coefficient R of the test substructure under the original load frequency and the adjusted load frequency is calculated according to formula (7): d1 and R d2 , R d2 / R d1 is the load adjustment factor after considering the amplification effect. The load amplitude and loading duration are recalculated through the above process.

[0164] Secondly, based on the load capacity limit of the swing table and the damage equivalence principle, the load amplitude and loading duration are adjusted using formula (8). If the load amplitude does not reach the load capacity limit, the load amplitude can be amplified to shorten the loading duration.

[0165] Ultimately, test parameters that meet the test requirements are determined. These test parameters include load amplitude, load frequency, and loading duration. These test parameters can be used to conduct full-scale vibration tests on the test substructure to determine the damage to the substructure during actual transportation (i.e., whether the structure is damaged).

[0166] Flexible direct current (HVDC) transmission technology is the preferred means of connecting large-scale offshore wind power to onshore power grids. Converter valves, the core components of HVDC transmission systems, are typically assembled onshore and transported by barge to the sea area where they are deployed. The harsh offshore transportation environment can cause converter valves to experience significant displacement, velocity, and acceleration, which can severely impact their mechanical properties, leading to fatigue damage and vibration damage to their internal structures, compromising their proper operation. Currently, no research exists to assess the structural safety of converter valves during offshore transportation, and testing of vibration resistance of these valves under maritime conditions is lacking.

[0167] Swing table testing can simulate the environmental excitation characteristics of converter valves during maritime transportation, allowing for assessment of the durability and safety of the structure. Due to the numerous limitations of test equipment, current testing is mostly performed on scaled models or prototypes of small structures. Given the large size and complex structure of converter valves, simple geometric scale model testing may not accurately reflect all similarity relationships. Specifically, different physical phenomena rely on different dimensionless similarity criteria, and simply adjusting the geometric scale cannot simultaneously satisfy all criteria. For example, if a scaled building model is constructed to test its seismic performance, geometric scaling alone may not accurately simulate the inertial and elastic forces of the material. For example, time scaling may require acceleration adjustments, while the material's elastic modulus and density may need to be adjusted proportionally. Otherwise, the model's vibration frequency and damping characteristics may not match the prototype, resulting in inaccurate test results. However, properly designed full-scale substructure testing can reflect the safety performance of key components and is more economical and convenient.

[0168] Therefore, addressing the current lack of testing in this area, this paper proposes a full-scale substructure test design method based on the fatigue damage equivalence principle. This method overcomes the current low test accuracy caused by limitations in the size and loading capacity of the swing platform, providing a test basis for fatigue analysis of converter valves during maritime transportation. The proposed test method can provide experimental verification for fatigue strength calculations of key converter valve components, and the test results can be used to update the finite element model of the test object and redesign the structure.

[0169] The present invention belongs to the technical field of fatigue damage test methods for flexible DC converter valves, and proposes a set of test methods suitable for fatigue damage analysis of converter valve substructures under wave loads during maritime transportation and for testing whether their fatigue strength meets the requirements. The test design includes four parts: selection of test substructures, stress equivalence of test substructures, fatigue damage equivalence of test substructures, and determination of test parameters. For the selection of test substructures, the part with the maximum stress is selected as the test substructure based on the dynamic response analysis results of the overall converter valve; for stress equivalence, the stress of the selected test substructure and the same part of the overall converter valve should be consistent as the basis for fatigue analysis; for fatigue damage equivalence, input excitation parameters with fewer cycles are obtained based on the damage equivalence principle; for test parameters, the test input excitation is further adjusted based on the load capacity limit of the swing table to shorten the test time.

[0170] In view of the current situation where full-scale vibration tests on large-scale equipment cannot be carried out and scaled tests cannot accurately reflect all similar relationships, the present invention provides a substructure full-scale test design method, which selects substructures based on the overall structural response, determines test parameters based on the damage equivalence principle, and then conducts physical tests. The present invention is a full-scale test design method that can actually reflect the actual situation, and the test parameters can meet the capacity limit requirements of the test equipment, and the design process is convenient and fast. It can provide experimental verification for the theoretical analysis and numerical simulation of the fatigue strength of key components of the converter valve, and provide a reference for the conduct of fatigue tests on marine transport electrical equipment.

[0171] Example 2

[0172] Based on the same inventive concept, the present invention also provides a full-scale testing system for marine equipment sub-components, comprising:

[0173] a substructure selection module for selecting stress concentration locations of the marine equipment as test substructures based on a simulation analysis of the structural dynamic responses of various locations of the marine equipment under wave loads during marine transportation, and extracting a motion power spectrum of the test substructure during the simulation analysis;

[0174] a power spectrum adjustment module, configured to adjust the motion power spectrum of the test substructure using a power spectrum adjustment coefficient to obtain a corrected motion power spectrum; and determine an actual number of cyclic actions based on a peak frequency of the corrected motion power spectrum and an actual shipping time;

[0175] an equivalent conversion module, configured to determine, based on the corrected motion power spectrum and the actual number of cyclic actions, a damage equivalence relationship of the test substructure using the fatigue damage equivalence principle and a three-interval method, and further determine an equivalent test load and the number of test cycles of the test substructure;

[0176] a full-scale test module, configured to perform a rocking table vibration full-scale test on a marine equipment subcomponent corresponding to the test substructure based on the equivalent test load, the number of test cycles, and a preset test load frequency;

[0177] The power spectrum adjustment coefficient is determined based on the structural dynamic response of the test substructure.

[0178] In a possible implementation, the marine equipment is a flexible DC converter valve, and the test substructure is a bottom submodule of the flexible DC converter valve.

[0179] In a possible implementation, the invention further includes a spectral coefficient determination module, wherein the spectral coefficient determination module is configured to:

[0180] extracting a dynamic response result of a test substructure from a simulation analysis result of a structural dynamic response of the marine equipment under wave load during marine transportation as a concentrated dynamic response of the test substructure;

[0181] Using the motion power spectrum of the bottom of the test substructure as input, performing structural dynamic response simulation on the test substructure to obtain a separate dynamic response of the test substructure;

[0182] The power spectrum adjustment coefficient is determined based on the ratio of the concentrated dynamic response to the individual dynamic response of the test substructure by utilizing the linear relationship between the load and the response of the marine equipment.

[0183] In a possible implementation, the equivalent conversion module includes:

[0184] an interval calculation submodule for calculating the load amplitude and the number of cycles corresponding to each interval using a three-interval method based on the corrected motion power spectrum and the actual number of cycles; and determining the fatigue life corresponding to each interval based on the relationship between the load amplitude corresponding to each interval and the SN curve of the test substructure;

[0185] a conversion submodule for determining an equivalent interval and an equivalent ratio based on the number of cycles and fatigue life corresponding to each interval, 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 number of test cycles corresponding to the equivalent ratio is equivalent to the sum of the fatigue damage of the load amplitudes corresponding to each interval, thereby obtaining the damage equivalence relationship;

[0186] The equivalent intervals belong to the three intervals corresponding to the three-interval method.

[0187] In a possible implementation, the load amplitude corresponding to each interval includes the load amplitude corresponding to one times the mean square error of the corrected motion power spectrum, the load amplitude corresponding to two times the mean square error of the corrected motion power spectrum, and the load amplitude corresponding to three times the mean square error of the corrected motion power spectrum.

[0188] In a possible implementation, the number of test cycles corresponding to each interval is 0.6831n, 0.271n, and 0.0433n, respectively, where n is the actual number of cycles.

[0189] In a possible implementation, the damage equivalence relationship is as follows:

[0190]

[0191] Where D is the sum of fatigue damage corresponding to the load amplitude in each interval, n 1σ 、n 2σ 、n3σ N is the number of test cycles under the load amplitude corresponding to one times the mean square error, two times the mean square error, and three times the mean square error of the corrected motion power spectrum; 1σ 、N 2σ 、N 3σ are respectively the fatigue life under the load amplitude corresponding to one times the mean square error, two times the mean square error, and three times the mean square error of the corrected motion power spectrum; a is the equivalent magnification, n xσ 、N xσ are the number of test cycles and fatigue life under the corresponding load amplitude in the equivalent interval, respectively; K is the load response linear relationship coefficient of the test substructure, C and k are material constants, A1, A2, and A3 are the load amplitudes corresponding to one times the mean square error, two times the mean square error, and three times the mean square error of the corrected motion power spectrum, respectively;

[0192] In a possible implementation, the equivalent test load is the load corresponding to the equivalent interval, and the number of test cycles is the number of cycles corresponding to the equivalent interval.

[0193] In a possible implementation, an amplitude adjustment module is further included, and the amplitude adjustment module includes:

[0194] an amplitude adjustment submodule, configured to adjust the amplitude of the equivalent test load using a load adjustment coefficient to obtain a test load amplitude;

[0195] a duration calculation submodule, configured to determine the test duration of the test substructure using the test load frequency and the number of test cycle actions;

[0196] Wherein, the load adjustment coefficient is determined based on the peak frequency of the motion power spectrum of the bottom of the test substructure and the test load frequency;

[0197] The full-scale test module is specifically used for:

[0198] A rocking table vibration full-scale test is performed on a marine equipment subcomponent corresponding to the test substructure based on the test load amplitude, the test duration and the preset test load frequency.

[0199] In a possible implementation, the amplitude adjustment module further includes an amplitude adjustment coefficient determination submodule, and the amplitude adjustment coefficient determination submodule is configured to:

[0200] determining a dynamic amplification factor of the wave load based on a peak frequency of a motion power spectrum of the test substructure and a natural frequency of a marine equipment subcomponent corresponding to the test substructure;

[0201] Determining a dynamic amplification factor of the rocking table test load based on the test load frequency and the natural frequency of the marine equipment subcomponent corresponding to the test substructure;

[0202] The load adjustment factor is determined based on a ratio of a dynamic amplification factor of the rocking table test load to a dynamic amplification factor of the wave load.

[0203] In a possible implementation, the system further includes a parameter scaling module, wherein the parameter scaling module is configured to:

[0204] If the test load amplitude is less than the swing amplitude limit of the swing platform, the ratio of the swing amplitude limit of the swing platform to the test load amplitude is calculated as the original amplification factor;

[0205] Determine the scaling relationship between the load amplitude and the duration of the test substructure based on the damage equivalence principle;

[0206] Adjusting the test duration based on the original amplification factor and the scaling correspondence between the load amplitude and the duration of the test substructure to obtain an adjusted test duration;

[0207] The full-scale test module is specifically used for:

[0208] A rocking table vibration full-scale test is performed on the marine equipment sub-component corresponding to the test sub-structure based on the rocking table's rocking amplitude limit, the adjusted test duration, and the test load frequency.

[0209] In a possible implementation, the scaling relationship between the load amplitude and the duration of the test substructure is as follows:

[0210]

[0211] Where, T b T is the duration of the experiment before scaling. b′ is the duration of the trial after scaling, A b is the load amplitude before scaling, A b′ is the scaled load amplitude, and k is the material constant.

[0212] Example 3

[0213] like Figure 6 As shown, the present invention also provides an electronic device, which may be a computer, a single-chip microcomputer, a smart mobile device, or the like. The electronic device in this embodiment may include a processor, a memory, a transceiver component, and the like. The memory, processor, and transceiver component are connected via a bus; the memory may be used to store an execution program, which may include instructions; and the processor may be used to execute the instructions stored in the memory. The memory may also be used to store data, which may be accessed and / or modified during the execution of the instructions.

[0214] The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) 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, which is suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in a storage medium to implement the corresponding method flow or corresponding function, so as to implement the steps of a full-scale test method for sub-components of marine equipment in the above embodiment.

[0215] Example 4

[0216] Based on the same inventive concept, the present invention also provides a readable storage medium, specifically an electronic device readable storage medium (Memory), which is a memory device in an electronic device for storing 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, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space. 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. The processor loads and executes one or more instructions stored in the storage medium, which can implement the steps of a full-scale test method for sub-components of marine equipment in the above embodiment.

[0217] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0218] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0219] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0220] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 The steps for the function specified in one or more boxes.

[0221] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit its scope of protection. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that after reading the present invention, those skilled in the art may still make various changes, modifications or equivalent substitutions to the specific implementation methods of the application, but these changes, modifications or equivalent substitutions are all within the scope of protection of the pending claims.

Claims

1. A full-scale test method for marine equipment sub-components, characterized in that: include: Based on the simulation analysis of the structural dynamic response of various parts of the marine equipment under the action of wave loads during sea transportation, the stress concentration parts of the marine equipment are selected as test substructures and the motion power spectrum of the test substructure is extracted during the simulation analysis; Using the power spectrum adjustment coefficient to adjust the motion power spectrum of the test substructure to obtain a corrected motion power spectrum; determining the actual number of cyclic actions based on the peak frequency of the corrected motion power spectrum and the actual sea transport time; Based on the corrected motion power spectrum and the actual number of cycles, the fatigue damage equivalence principle and the three-interval method are used to determine the damage equivalence relationship of the test substructure, and then the equivalent test load and the number of test cycles of the test substructure are determined; Performing a rocking table vibration full-scale test on a marine equipment subcomponent corresponding to the test substructure based on the equivalent test load, the number of test cycles, and a preset test load frequency; The power spectrum adjustment coefficient is determined based on the structural dynamic response of the test substructure.

2. The method according to claim 1, characterized in that The marine equipment is a flexible DC converter valve, and the test substructure is a bottom submodule of the flexible DC converter valve.

3. The method according to claim 1, characterized in that Before adjusting the motion power spectrum of the test substructure using the power spectrum adjustment coefficient to obtain a corrected motion power spectrum, the method further includes: extracting a dynamic response result of a test substructure from a simulation analysis result of a structural dynamic response of the marine equipment under wave load during marine transportation as a concentrated dynamic response of the test substructure; Using the motion power spectrum of the bottom of the test substructure as input, performing structural dynamic response simulation on the test substructure to obtain a separate dynamic response of the test substructure; The power spectrum adjustment coefficient is determined based on the ratio of the concentrated dynamic response to the individual dynamic response of the test substructure by utilizing the linear relationship between the load and the response of the marine equipment.

4. The method according to claim 1, wherein Based on the corrected motion power spectrum and the actual number of cyclic actions, the fatigue damage equivalence principle and the three-interval method are used to determine the damage equivalence relationship of the test substructure, including: Based on the corrected motion power spectrum and the actual number of cyclic actions, the load amplitude and the number of cyclic actions corresponding to each interval are calculated using a three-interval method; Determine the fatigue life corresponding to each interval based on the load amplitude corresponding to each interval and the SN curve relationship of the test substructure; Based on the number of cycles and fatigue life corresponding to each interval, the equivalent interval and equivalent ratio are determined 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 number of test cycles corresponding to the equivalent ratio is equivalent to the sum of the fatigue damage of the load amplitude corresponding to each interval, thereby obtaining the damage equivalence relationship; The equivalent intervals belong to the three intervals corresponding to the three-interval method.

5. The method according to claim 4, characterized in that The load amplitude corresponding to each interval includes the load amplitude corresponding to one times the mean square error of the corrected motion power spectrum, the load amplitude corresponding to two times the mean square error of the corrected motion power spectrum, and the load amplitude corresponding to three times the mean square error of the corrected motion power spectrum.

6. The method according to claim 4, characterized in that The test cycle times corresponding to each interval are 0.6831n, 0.271n and 0.0433n, respectively, where n is the actual cycle times.

7. The method according to claim 5, characterized in that The damage equivalence relationship is as follows: Where D is the sum of fatigue damage corresponding to the load amplitude in each interval, n 1σ 、n 2σ 、n 3σ N is the number of test cycles under the load amplitude corresponding to one times the mean square error, two times the mean square error, and three times the mean square error of the corrected motion power spectrum; 1σ 、N 2σ 、N 3σ are respectively the fatigue life under the load amplitude corresponding to one times the mean square error, two times the mean square error, and three times the mean square error of the corrected motion power spectrum; a is the equivalent magnification, n xσ 、N xσ are the number of test cycles and fatigue life under the corresponding load amplitude in the equivalent interval, respectively; K is the linear relationship coefficient of the load response of the test substructure, C and k are the material constants, A1, A2, and A3 are the load amplitudes corresponding to one times the mean square deviation, two times the mean square deviation, and three times the mean square deviation of the corrected motion power spectrum, respectively.

8. The method according to claim 4, characterized in that The equivalent test load is the load corresponding to the equivalent interval, and the number of test cycles is the number of cycles corresponding to the equivalent interval.

9. The method according to claim 1, characterized in that After determining the damage equivalence relationship of the test substructure based on the corrected motion power spectrum and the actual number of cycles using the fatigue damage equivalence principle and the three-interval method, and then determining the equivalent test load and the number of test cycles of the test substructure, the method further includes: Using the load adjustment coefficient to adjust the amplitude of the equivalent test load to obtain the test load amplitude; Determining the test duration of the test substructure using the test load frequency and the number of test cycle actions; Wherein, the load adjustment coefficient is determined based on the peak frequency of the motion power spectrum of the bottom of the test substructure and the test load frequency; The step of performing a rocking table vibration full-scale test on a marine equipment subcomponent corresponding to the test substructure based on the equivalent test load, the number of test cycles, and a preset test load frequency includes: A rocking table vibration full-scale test is performed on a marine equipment subcomponent corresponding to the test substructure based on the test load amplitude, the test duration and the preset test load frequency.

10. The method according to claim 9, characterized in that Before adjusting the amplitude of the equivalent test load by using the load adjustment coefficient to obtain the test load amplitude, the method further includes: determining a dynamic amplification factor of the wave load based on a peak frequency of a motion power spectrum of the test substructure and a natural frequency of a marine equipment subcomponent corresponding to the test substructure; Determining a dynamic amplification factor of the rocking table test load based on the test load frequency and the natural frequency of the marine equipment subcomponent corresponding to the test substructure; The load adjustment factor is determined based on a ratio of a dynamic amplification factor of the rocking table test load to a dynamic amplification factor of the wave load.

11. The method according to claim 9, characterized in that After determining the test duration of the test substructure using the test load frequency and the number of test cycles, the method further includes: If the test load amplitude is less than the swing amplitude limit of the swing platform, the ratio of the swing amplitude limit of the swing platform to the test load amplitude is calculated as the original amplification factor; Determine the scaling relationship between the load amplitude and the duration of the test substructure based on the damage equivalence principle; Adjusting the test duration based on the original amplification factor and the scaling correspondence between the load amplitude and the duration of the test substructure to obtain an adjusted test duration; The step of performing a rocking table vibration full-scale test on a marine equipment subcomponent corresponding to the test substructure based on the test load amplitude, the test duration, and a preset test load frequency includes: A rocking table vibration full-scale test is performed on the marine equipment sub-component corresponding to the test sub-structure based on the rocking table's rocking amplitude limit, the adjusted test duration, and the test load frequency.

12. The method according to claim 11, characterized in that The scaling relationship between the load amplitude and duration of the test substructure is as follows: Where, T b T is the duration of the experiment before scaling. b′ is the duration of the trial after scaling, A b is the load amplitude before scaling, A b′ is the scaled load amplitude, and k is the material constant.

13. A full-scale testing system for marine equipment sub-components, characterized in that: include: a substructure selection module for selecting stress concentration locations of the marine equipment as test substructures based on a simulation analysis of the structural dynamic responses of various locations of the marine equipment under wave loads during marine transportation, and extracting a motion power spectrum of the test substructure during the simulation analysis; a power spectrum adjustment module, configured to adjust the motion power spectrum of the test substructure using a power spectrum adjustment coefficient to obtain a corrected motion power spectrum; and determine an actual number of cyclic actions based on a peak frequency of the corrected motion power spectrum and an actual shipping time; an equivalent conversion module, configured to determine, based on the corrected motion power spectrum and the actual number of cyclic actions, a damage equivalence relationship of the test substructure using the fatigue damage equivalence principle and a three-interval method, and further determine an equivalent test load and the number of test cycles of the test substructure; a full-scale test module, configured to perform a rocking table vibration full-scale test on a marine equipment subcomponent corresponding to the test substructure based on the equivalent test load, the number of test cycles, and a preset test load frequency; The power spectrum adjustment coefficient is determined based on the structural dynamic response of the test substructure.

14. The system according to claim 13, wherein: The marine equipment is a flexible DC converter valve, and the test substructure is a bottom submodule of the flexible DC converter valve.

15. The system according to claim 13, wherein: The invention also includes a spectrum coefficient determination module, wherein the spectrum coefficient determination module is used to: extracting a dynamic response result of a test substructure from a simulation analysis result of a structural dynamic response of the marine equipment under wave load during marine transportation as a concentrated dynamic response of the test substructure; Using the motion power spectrum of the bottom of the test substructure as input, performing structural dynamic response simulation on the test substructure to obtain a separate dynamic response of the test substructure; The power spectrum adjustment coefficient is determined based on the ratio of the concentrated dynamic response to the individual dynamic response of the test substructure by utilizing the linear relationship between the load and the response of the marine equipment.

16. The system according to claim 13, wherein: The equivalent conversion module includes: an interval calculation submodule for calculating the load amplitude and the number of cycles corresponding to each interval using a three-interval method based on the corrected motion power spectrum and the actual number of cycles; and determining the fatigue life corresponding to each interval based on the relationship between the load amplitude corresponding to each interval and the SN curve of the test substructure; a conversion submodule for determining an equivalent interval and an equivalent ratio based on the number of cycles and fatigue life corresponding to each interval, 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 number of test cycles corresponding to the equivalent ratio is equivalent to the sum of the fatigue damage of the load amplitudes corresponding to each interval, thereby obtaining the damage equivalence relationship; The equivalent intervals belong to the three intervals corresponding to the three-interval method.

17. The system according to claim 16, wherein: The load amplitude corresponding to each interval includes the load amplitude corresponding to one times the mean square error of the corrected motion power spectrum, the load amplitude corresponding to two times the mean square error of the corrected motion power spectrum, and the load amplitude corresponding to three times the mean square error of the corrected motion power spectrum.

18. The system according to claim 16, wherein: The test cycle times corresponding to each interval are 0.6831n, 0.271n and 0.0433n, respectively, where n is the actual cycle times.

19. The system according to claim 17, wherein: The damage equivalence relationship is as follows: Where D is the sum of fatigue damage corresponding to the load amplitude in each interval, n 1σ 、n 2σ 、n 3σ N is the number of test cycles under the load amplitude corresponding to one times the mean square error, two times the mean square error, and three times the mean square error of the corrected motion power spectrum; 1σ 、N 2σ 、N 3σ are respectively the fatigue life under the load amplitude corresponding to one times the mean square error, two times the mean square error, and three times the mean square error of the corrected motion power spectrum; a is the equivalent magnification, n xσ 、N xσ are the number of test cycles and fatigue life under the corresponding load amplitude in the equivalent interval, respectively; K is the linear relationship coefficient of the load response of the test substructure, C and k are the material constants, A1, A2, and A3 are the load amplitudes corresponding to one times the mean square deviation, two times the mean square deviation, and three times the mean square deviation of the corrected motion power spectrum, respectively.

20. The system according to claim 16, wherein: The equivalent test load is the load corresponding to the equivalent interval, and the number of test cycles is the number of cycles corresponding to the equivalent interval.

21. The system according to claim 13, wherein: The system further includes an amplitude adjustment module, wherein the amplitude adjustment module includes: an amplitude adjustment submodule, configured to adjust the amplitude of the equivalent test load using a load adjustment coefficient to obtain a test load amplitude; a duration calculation submodule, configured to determine the test duration of the test substructure using the test load frequency and the number of test cycle actions; Wherein, the load adjustment coefficient is determined based on the peak frequency of the motion power spectrum of the bottom of the test substructure and the test load frequency; The full-scale test module is specifically used for: A rocking table vibration full-scale test is performed on a marine equipment subcomponent corresponding to the test substructure based on the test load amplitude, the test duration and the preset test load frequency.

22. The system according to claim 21, wherein: The amplitude adjustment module further includes an amplitude adjustment coefficient determination submodule, and the amplitude adjustment coefficient determination submodule is used to: determining a dynamic amplification factor of the wave load based on a peak frequency of a motion power spectrum of the test substructure and a natural frequency of a marine equipment subcomponent corresponding to the test substructure; Determining a dynamic amplification factor of the rocking table test load based on the test load frequency and the natural frequency of the marine equipment subcomponent corresponding to the test substructure; The load adjustment factor is determined based on a ratio of a dynamic amplification factor of the rocking table test load to a dynamic amplification factor of the wave load.

23. The system according to claim 21, wherein: The module further includes a parameter scaling module, wherein the parameter scaling module is configured to: If the test load amplitude is less than the swing amplitude limit of the swing platform, the ratio of the swing amplitude limit of the swing platform to the test load amplitude is calculated as the original amplification factor; Determine the scaling relationship between the load amplitude and the duration of the test substructure based on the damage equivalence principle; Adjusting the test duration based on the original amplification factor and the scaling correspondence between the load amplitude and the duration of the test substructure to obtain an adjusted test duration; The full-scale test module is specifically used for: A rocking table vibration full-scale test is performed on the marine equipment sub-component corresponding to the test sub-structure based on the rocking table's rocking amplitude limit, the adjusted test duration, and the test load frequency.

24. The system according to claim 23, wherein: The scaling relationship between the load amplitude and duration of the test substructure is as follows: Where, T b T is the duration of the experiment before scaling. b′ is the duration of the trial after scaling, A b is the load amplitude before scaling, A b′ is the scaled load amplitude, and k is the material constant.

25. An electronic device, characterized in that: include: at least one processor and memory; The memory and the processor are connected via 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 12 is implemented.

26. A readable storage medium, characterized in that An execution program is stored thereon, and when the execution program is executed, the method according to any one of claims 1 to 12 is implemented.

Images