A ship electric power mechanical coupling fault intelligent grading diagnosis method, device and medium

Abstract

This invention relates to the field of ship power system operation assessment, and discloses an intelligent hierarchical diagnosis method, equipment, and medium for ship electromechanical coupling faults. The method includes: collecting multimodal parameters of the ship power system operation; calculating dynamic weight parameters for the multimodal parameters using the sliding window variance method; fusing the entropy values ​​of the multimodal parameters based on the dynamic weight parameters to calculate a coupling strength index; and performing intelligent hierarchical diagnosis of ship power system faults and specifying corresponding protection strategies based on the coupling strength index. This invention provides strong technical support for the safe and stable operation of ship power systems, promotes the development of ship power system fault diagnosis and protection technologies, and has broad application prospects and significant practical value.

Description

Technical Field

[0001] This invention relates to the field of ship power system operation assessment, and in particular to a method, equipment and medium for intelligent hierarchical diagnosis of ship electromechanical coupling faults. Background Technology

[0002] Against the backdrop of the rapid development of the modern shipbuilding industry, the scale and complexity of ship electrical systems are constantly increasing, making them a key support system for ship operation. Ship electrical systems not only need to provide stable power to various electrical devices, but also need to work closely with propulsion systems, mechanical devices, and other components to ensure the safe and efficient navigation of the ship.

[0003] With the increasing electrification of ships, especially the widespread application of a large number of high-power-density electrical devices (such as frequency converters and automated control systems), the electro-mechanical coupling phenomenon has become increasingly prominent. This coupling means that the operating state of the ship's electrical system is affected by both electrical and mechanical factors, increasing the complexity and uncertainty of the system's operating state.

[0004] Traditional fault diagnosis methods for ship electrical systems primarily rely on the monitoring and analysis of single parameters (such as voltage and current), neglecting the dynamic relationship between these parameters and the operating status of the mechanical system. In actual operation, problems such as harmonic distortion and power fluctuations in the electrical system are often interrelated with and influence each other on the vibration and torque changes of the mechanical system. This complex coupling makes it difficult for traditional diagnostic methods to accurately identify fault types and locations, leading to misdiagnosis and missed diagnosis. Consequently, timely and effective protective measures cannot be taken, increasing the risk of ship electrical system failures.

[0005] Furthermore, when a ship's electrical system fails, most existing protection mechanisms are uniform, fixed-parameter protection methods, lacking the ability to classify and handle cases according to the severity of the fault and actual operating conditions. This "one-size-fits-all" protection approach may lead to premature and excessive protective actions in the early stages of a fault, affecting the normal operation of the ship; or, in the event of a serious fault, it may fail to disconnect critical equipment in a timely manner, thereby expanding the scope of the fault's impact and causing greater losses.

[0006] Therefore, there is an urgent need for a diagnostic method that can comprehensively consider multimodal information of electrical and mechanical systems, assess the system's operating status in real time, and perform intelligent hierarchical protection to improve the reliability, stability, and safety of ship power systems and meet the complex and ever-changing operational needs of modern ships. Summary of the Invention

[0007] The purpose of this invention is to propose an intelligent hierarchical diagnosis method, equipment, and medium for ship electromechanical coupling faults, thereby solving the technical problems that existing ship power system fault diagnosis methods are not accurate enough, cannot cope with different situations, and have poor reliability.

[0008] Specifically, the present invention provides a method, equipment, and medium for intelligent hierarchical diagnosis of ship electromechanical coupling faults, the method comprising the following steps:

[0009] S1. Collect multimodal parameters of the ship's electrical system operation;

[0010] S2. The sliding window variance method is used to calculate the dynamic weight parameters of the multimodal parameters;

[0011] S3. Based on dynamic weight parameters, multimodal parameters are fused to calculate the coupling strength index;

[0012] S4. Based on the coupling strength index, perform intelligent classification diagnosis of ship power system faults and specify corresponding protection strategies.

[0013] A storage medium storing instructions and data for implementing an intelligent hierarchical diagnosis method for ship electromechanical coupling faults.

[0014] A smart classification and diagnosis device for ship electromechanical coupling faults includes: a processor and a storage medium; the processor loads and executes instructions and data in the storage medium to implement a smart classification and diagnosis method for ship electromechanical coupling faults.

[0015] The beneficial effects provided by this invention are: this method can deeply explore the complex coupling relationships between multiple source parameters such as electrical and mechanical components, overcoming the problems of misjudgment and omission caused by traditional methods due to single parameters or insufficient consideration of coupling relationships. Through the fusion analysis of real-time monitoring data, a more accurate fault characteristic model and diagnostic rules are established, enabling early warning and precise diagnosis of various potential faults. The technical achievements of this invention will be widely applied to various ship power systems, providing a solid technical guarantee for the safe navigation and efficient operation of ships, and possessing significant theoretical and practical application value. Attached Figure Description

[0016] Figure 1 This is a simplified flowchart of the method of the present invention;

[0017] Figure 2 This is a schematic diagram of the hierarchical diagnosis and protection strategy of the present invention;

[0018] Figure 3 This is a schematic diagram of the hardware device operation according to an embodiment of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0020] Before formally describing the present invention, a general description of the solution of the present invention will be given first to facilitate understanding.

[0021] Please refer to Figure 1 The present invention provides an intelligent hierarchical diagnosis method for ship electromechanical coupling faults, comprising:

[0022] S1. Collect multimodal parameters of the ship's electrical system operation;

[0023] The multimodal parameters mentioned in step S1 include: electrical parameters, mechanical parameters, and thermodynamic parameters.

[0024] It should be noted that the electrical parameters include: power grid harmonic distortion rate (THD), harmonic current data, and voltage signal; the mechanical parameters include: crankshaft torsional amplitude and bearing vibration data; and the thermodynamic parameters include: turbine inlet exhaust temperature and cooling water temperature difference.

[0025] As one example, during the operation of a ship's electrical system, various key parameters are collected in real time, covering multiple fields such as electrical, mechanical, and thermal aspects, to ensure a comprehensive reflection of the system's operating status. Specifically, this includes:

[0026] a) Electrical parameter acquisition: Using a high-precision power analyzer (such as Hioki 3196), accurately measure the power grid harmonic distortion rate (THD) at a sampling rate of not less than 12.8kHz; use a Rogowski coil (LEM LF 510-S) as a current sensor to accurately acquire harmonic current data within a bandwidth of 0-5kHz; and achieve high-precision acquisition of voltage signals through an isolation amplifier (ADUM 3190).

[0027] b) Mechanical parameter acquisition: Fiber Bragg grating (FBG) strain gauges with a resolution of up to 0.001° are installed in key parts of the ship's shafting system to accurately measure the crankshaft torsional amplitude; vibration accelerometers (PCB352C33) are reasonably arranged near the bearing housing to collect vibration data at a sampling rate of 50kHz, thereby monitoring the mechanical vibration.

[0028] c) Thermal parameter acquisition: Using an infrared thermometer, the turbine inlet exhaust temperature is accurately measured in accordance with EN 334 standard to ensure the measurement accuracy is within ±1℃; the cooling water temperature difference is monitored in real time through a temperature difference sensor with a range set to 0-100℃ to monitor the status of the thermal system.

[0029] S2. The sliding window variance method is used to calculate the dynamic weight parameters of the multimodal parameters;

[0030] To more accurately reflect the importance of each parameter in the system, this invention employs the sliding window variance method to dynamically calculate the weights of multiple parameters. By analyzing the changing characteristics of each parameter in real time, the weight coefficients are dynamically adjusted to adapt to the needs of the ship under different operating conditions.

[0031] Specifically:

[0032] a) Taking the power grid harmonic distortion rate (THD) as an example, calculate its variance σ within the time window t. 2 THD (t), measures the degree of volatility of THD. This variance can be calculated using the following formula:

[0033]

[0034] Where N is the number of sampling points within the time window, THD i Let THD be the value of the i-th sampling point. This represents the average THD value within that time window.

[0035] b) Determine if a sudden change has occurred by combining the rate of change of THD |dTHD / dt|. When |dTHD / dt| > 3% / s, it indicates that the THD is changing drastically. In this case, increase the mutation sensitivity coefficient α (from the default value of 0.3 to 0.5) to enhance the response to abnormal situations such as sudden load increases. At the same time, set the smoothing constant β = 0.01 to prevent division by zero errors.

[0036] c) Integrating information from various parameters, calculate the dynamic weight ω of the power grid harmonic distortion rate (THD) using the following formula. THD (t):

[0037]

[0038] Where σ 2 torsion (t) represents the variance of the crankshaft torsional amplitude within the time window t.

[0039] The dynamic weighting coefficient ω of the crankshaft torsional amplitude torsion The formula for calculating (t) is as follows:

[0040] S3. Based on dynamic weight parameters, multimodal parameters are fused to calculate the coupling strength index;

[0041] Based on the calculation of dynamic weights, this invention uses an entropy fusion model to fuse multi-parameter information, calculate the coupling strength index (EH), and comprehensively assess the degree of power-mechanical coupling faults.

[0042] a) First, the collected parameters such as THD, crankshaft torsional amplitude (Atorsion), and excitation current fluctuation rate (ΔIf) are standardized to ensure that each parameter is calculated under the same dimension.

[0043] b) Then, based on the dynamic weight calculation results, the standardized parameters are multiplied by their corresponding weights and summed, then multiplied by a logarithmic term to obtain the coupling strength index E. H The calculation formula is as follows:

[0044]

[0045] This formula is used to calculate the coupling strength index E of a ship's electromechanical coupling system. H (t), which integrates electrical parameters (THD) and mechanical parameters (crankshaft torsional amplitude A). torsion And electrical stability parameters (excitation current fluctuation rate ΔIf), through dynamic weight w THD (t) and w torsion (t) We take a weighted sum of the parameters and combine it with a logarithmic function to measure the coupling strength of the system within the time window t. The parameters are explained below:

[0046] n: Represents the number of sampling points. When calculating the coupling strength index, data from multiple sampling times needs to be processed, and n is the total number of these sampling points. For example, if data is collected at regular intervals within a time period, n is the number of times data is collected within that time period.

[0047] ω THD (t) represents the dynamic weight of the electrical parameter (THD) at time t. It reflects the degree of influence of THD on the coupling strength of the system at the current time.

[0048] ω torsion (t) represents the dynamic weight of the mechanical parameter (crankshaft torsional amplitude) at time t. Similar to wTHD(t), it is also dynamically adjusted according to the system's operating state and is used to measure the degree of influence of the crankshaft torsional amplitude on the system's coupling strength at the current moment.

[0049] THD i This represents the harmonic distortion rate (THD) of the power grid at the i-th sampling time. It is the ratio of the effective value of harmonic voltage or current to the effective value of fundamental voltage or current in the power grid, reflecting the quality of power grid power. The higher the THD value, the greater the harmonic content in the power grid, which may have adverse effects on electrical equipment.

[0050] THD maxThis represents the maximum limit for harmonic distortion rate of the ship's electrical network, typically taken as 10%. This is the maximum permissible harmonic distortion rate for ship electrical networks as specified in relevant International Electrotechnical Commission (IEC) standards (such as IEC 61000-3-6). In the formula, Used to transfer the actual THD i The values ​​are normalized to the [0,1] interval for comprehensive calculation with other parameters.

[0051] A crit The safe threshold for crankshaft torsional amplitude is typically set at 0.1°, determined based on the design and operational requirements of the ship's mechanical systems. When the crankshaft torsional amplitude exceeds this threshold, it may damage the ship's propulsion system and shafting, affecting the ship's safe operation.

[0052] A torsion,i This represents the crankshaft torsional vibration amplitude at the i-th sampling moment; it reflects the shaft torsional vibration caused by various excitations (such as uneven force of the propeller, torque fluctuation of the diesel engine, etc.) during the operation of the ship's propulsion system. This value is used to measure the magnitude of crankshaft torsional vibration relative to a safety threshold. The larger the value, the closer the crankshaft torsional vibration is to or beyond the safety threshold, and the greater its impact on the system.

[0053] ΔI f,i This represents the excitation current fluctuation rate at the i-th sampling time; the excitation current is the current used in the generator to generate the magnetic field, and its fluctuation affects the generator's output voltage and power stability. ΔI f,i This reflects the relative change of the excitation current at the sampling time, and the calculation formula is usually as follows: It is the actual excitation current at the i-th sampling time, I f,ref It is the reference excitation current.

[0054] K represents the excitation current gain coefficient, and the experimentally measured optimal value is 10. In the formula, Used to normalize the excitation current fluctuation rate. This involves performing a nonlinear transformation on the normalized excitation current fluctuation rate to reflect its impact on the system coupling strength. When the excitation current fluctuation is small, The value is close to 0; when the excitation current fluctuates greatly, the value will gradually increase, thus reflecting the increased influence of the excitation current fluctuation on the system coupling strength.

[0055] In summary, by comprehensively considering these parameters and their interrelationships, the formula EH(t) can comprehensively evaluate the operating status and fault risk of the ship's electromechanical coupling system at time t.

[0056] S4. Perform intelligent hierarchical diagnosis on the faults of the ship power system according to the coupling strength index and specify corresponding protection strategies.

[0057] The intelligent hierarchical diagnosis in step S4 specifically refers to:

[0058] When the coupling strength index does not exceed the first preset value, it indicates that there are potential risks in the ship power system. At this time, the protection strategy is to enter the warning state;

[0059] When the coupling strength index is greater than the first preset value but does not exceed the second preset value, it indicates that a relatively serious fault has occurred in the ship power system. At this time, the protection strategy is to trigger a serious protection action;

[0060] When the coupling strength index is greater than the second preset value, it indicates that there is a serious fault in the ship power system. At this time, the protection strategy is to trigger an emergency protection action.

[0061] Please refer to Figure 2 , Figure 2 which is the schematic diagram of the hierarchical diagnosis and protection strategy process of the present invention; As an embodiment, according to the value of the coupling strength index EH, the present invention sets different levels of protection strategies to ensure that appropriate protection measures can be taken in various fault situations, minimizing the impact of faults on the ship power system.

[0062] a) Emergency-level protection (EH > 0.9): When EH is greater than 0.9, it indicates that a serious fault has occurred in the ship power system, which may pose a serious threat to the equipment and the safety of the ship. At this time, the system immediately triggers an emergency protection action, quickly disconnects the loads of the top three harmonic sources (priority: auxiliary thruster > cargo pump > electric heater), and at the same time reduces the diesel engine speed to the safety threshold at a slope of 3% / s, and activates the active filter for transient compensation to suppress the impact of harmonic current on the system.

[0063] b) Serious-level protection (0.7 < EH ≤ 0.9): When EH is between 0.7 and 0.9, it indicates that a relatively serious fault has occurred in the system, but it has not reached the level of an emergency. At this time, the system triggers a serious protection action, starts the standby lubricating pump, increases the oil pressure by 10%, ensures the normal lubrication of mechanical equipment; at the same time, limits the generator output power to 90% of the rated value to avoid overloading of equipment; and triggers an audible and visual alarm to remind the operator to pay attention.

[0064] c) Warning-level protection (EH ≤ 0.7): When EH is less than or equal to 0.7, it indicates that there are certain potential fault risks in the system, but it has not had a substantial impact on the equipment. At this time, the system enters the warning state, records complete fault characteristic data, including the change trends of various parameters, the time of fault occurrence and other information; at the same time, generates a maintenance suggestion report to provide a reference basis for subsequent equipment maintenance.

[0065] Please see Figure 3 , Figure 3 This is a schematic diagram of the hardware device in operation according to an embodiment of the present invention. The hardware device specifically includes: a ship electromechanical coupling fault intelligent hierarchical diagnosis device 401, a processor 402, and a storage medium 403.

[0066] A ship electromechanical coupling fault intelligent classification and diagnosis device 401: The ship electromechanical coupling fault intelligent classification and diagnosis device 401 implements the ship electromechanical coupling fault intelligent classification and diagnosis method.

[0067] Processor 402: The processor 402 loads and executes the instructions and data in the storage medium 403 to implement the intelligent hierarchical diagnosis method for ship electromechanical coupling faults.

[0068] Storage medium 403: The storage medium 403 stores instructions and data; the storage medium 403 is used to implement the intelligent hierarchical diagnosis method for ship electromechanical coupling faults.

[0069] The present invention provides an embodiment as follows:

[0070] Using a case study of a large cargo ship, this paper describes in detail the operation process in practical applications.

[0071] During a typical ocean voyage, a significant anomaly occurred in the ship's electrical system of a large cargo ship. This anomaly was precisely detected by the ship's electrical monitoring system, and the specific fault characteristics are as follows:

[0072] 1) Sudden change in harmonic distortion rate (THD): THD, as one of the key indicators for measuring power grid quality, is normally maintained at around 3%. However, at the moment of this fault, THD rose sharply from 3% to 9%. This significant change indicates a substantial increase in harmonic content in the power grid, which may be caused by factors such as sudden load changes, power equipment failure, or electromagnetic interference.

[0073] 2) Increased crankshaft torsional vibration amplitude: Simultaneously, the crankshaft torsional vibration amplitude in the ship's propulsion system also changed significantly. Under normal operating conditions, the crankshaft torsional vibration amplitude remains at a stable, low level. However, during this failure, the crankshaft torsional vibration amplitude reached 0.12°. This value exceeds the normal operating fluctuation range, indicating that the shafting system may have been subjected to abnormal excitation forces, triggering torsional vibration.

[0074] 3) Fluctuation of excitation current: The excitation current is one of the key parameters for the normal operation of the generator, and its fluctuation directly affects the output stability of the generator. In this fault scenario, the excitation current volatility shows abnormal fluctuations, reaching 18%. Such fluctuations may lead to unstable output voltage of the generator, further affecting the normal operation of the entire ship power system.

[0075] Response made according to the method and system of the present invention:

[0076] 1) t = 15 ms: Dynamic weight adjustment

[0077] When it is monitored that THD suddenly increases from 3% to 9% instantaneously, the data acquisition module quickly transmits various parameter information collected in real time to the analysis and calculation module. After receiving the data, the analysis and calculation module immediately starts the dynamic weight calculation program.

[0078] During the calculation process, since the change rate of THD, ∣dTHD / dt∣, is significantly greater than 3% / s (the actual calculated ∣dTHD / dt∣ = 150% / s, far exceeding the threshold of 3% / s), it indicates that the change of THD is drastic. According to the dynamic weight calculation rule, at this time, the mutation sensitivity coefficient α is increased from the default value of 0.3 to 0.6 to enhance the response ability to abnormal situations such as sudden load addition. At the same time, the smoothing constant β remains 0.01 to prevent division-by-zero errors.

[0079] For example, when calculating the variance σTHD2(t) of THD within the time window t, since the time window is selected as 10 seconds and numerous THD sampling point data (assumed to be 1000) are collected within these 10 seconds, the specific value of σTHD2(t) is obtained through the formula. Similarly, other relevant parameters can be calculated for subsequent weight calculation, and finally the adjusted dynamic weight is obtained.

[0080] 2) t = 60 ms: Fault determination and triggering of protection action

[0081] After about 45 ms (from t = 15 ms to t = 60 ms) of data analysis and calculation, the system obtains the coupling strength index EH = 0.92. According to the pre-set hierarchical protection rules, when the EH value is greater than 0.9, it is an emergency-level protection; when 0.7 < EH ≤ 0.9, it is a severe-level protection; when EH ≤ 0.7, it is a warning-level protection. Therefore, this fault is determined to be an emergency-level protection fault.

[0082] After the system determines that it is an emergency-level protection fault, it immediately triggers an emergency protection action. First, the Energy Management Center (EMC) sends instructions to the switchgear of the power system to quickly cut off the top three harmonic source loads. These three loads are the main harmonic generation sources in the ship power system. Cutting them off can effectively reduce the harmonic content in the power grid and reduce the interference of harmonics to other equipment.

[0083] At the same time, the diesel engine control system receives a command to reduce the diesel engine speed from the current rated speed (let's say 1500 rpm) to a pre-set safety threshold (e.g., 1200 rpm) at a rate of 3% / s. This speed adjustment process is carried out gradually to ensure stable operation of the diesel engine and avoid mechanical failures caused by a sudden drop in speed.

[0084] In addition, the active power filter control unit is also activated, initiating transient compensation for the power grid. The active power filter quickly suppresses the impact of harmonic currents on the system and restores the voltage and current quality of the power grid by detecting harmonic currents in the power grid in real time and generating a compensation current of equal magnitude but opposite direction.

[0085] 3) t = 80ms: The system returns to normal.

[0086] After approximately 20 ms (from t=60ms to t=80ms) of protective actions, the harmonic source cutoff, diesel engine speed adjustment, and transient compensation of the active filter took effect. At this time, the THD value dropped from 9% to 4%, and the crankshaft torsional amplitude also decreased from 0.12° to 0.09°. Both of these key parameters returned to near normal operating ranges, indicating that the ship's electrical system had basically stabilized and the system had returned to normal operation.

[0087] Through the above specific implementation methods, the intelligent hierarchical diagnosis method for ship electromechanical coupling faults based on multimodal dynamic entropy weight fusion of the present invention has been effectively verified. In the complex operating environment of ship power systems, the system can intelligently and accurately analyze the operating status of the ship power system based on real-time collected multi-source heterogeneous data, including relevant parameters from the electrical, mechanical, and thermal fields, through dynamic weight calculation and entropy value fusion evaluation modules. The comprehensive consideration of multimodal data and the adaptive adjustment of dynamic weights ensure that the diagnostic results are not affected by a single factor, effectively overcoming the false alarms and missed alarms that are prone to occur in traditional diagnostic methods when facing complex operating conditions, and greatly improving the accuracy of fault diagnosis.

[0088] From an economic perspective, accurate fault diagnosis and efficient response and protection mechanisms significantly reduce unplanned downtime caused by ship malfunctions, lower maintenance costs and operational losses, and improve the overall economic efficiency of ship operation.

[0089] In summary, the beneficial effects of this invention are as follows: From the perspective of fault diagnosis and protection of ship electrical systems, this invention, through dynamic weight calculation and entropy fusion evaluation, can adaptively fuse multimodal parameter information, accurately identify electro-mechanical coupling faults, and achieve efficient handling of faults of varying severity through a hierarchical protection strategy, thus possessing the following significant advantages:

[0090] High diagnostic accuracy: By fully considering the coupling relationship between electrical and mechanical parameters and dynamically adjusting the weights, the false alarm rate and false negative rate are effectively reduced. Compared with traditional methods, the accuracy of fault diagnosis under complex working conditions is significantly improved.

[0091] Fast response speed: The hierarchical protection mechanism can respond to different levels of faults within milliseconds, which greatly shortens the fault handling time, reduces the risk of fault escalation, and improves the safety and reliability of the ship's electrical system.

[0092] Highly adaptable: It can adaptively adjust diagnostic and protection strategies according to the actual operating conditions and parameter changes of the ship, and is suitable for various types of ships and complex marine environments.

[0093] Good economic efficiency: Accurate fault diagnosis and efficient protection measures reduce unnecessary equipment downtime and maintenance costs, while reducing operational losses caused by faults and improving the economic efficiency of ship operation.

[0094] In summary, this invention provides strong technical support for the safe and stable operation of ship power systems, promotes the development of fault diagnosis and protection technologies for ship power systems, and has broad application prospects and important practical value.

[0095] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An intelligent hierarchical diagnosis method for ship electric machinery coupling fault, characterized in that: Includes the following steps: S1. Collect multimodal parameters of the ship's electrical system operation; S2. The sliding window variance method is used to calculate the dynamic weight parameters of the multimodal parameters; S3. Based on dynamic weight parameters, multimodal parameters are fused by entropy values ​​to calculate the coupling strength index; S4. Based on the coupling strength index, perform intelligent hierarchical diagnosis of ship power system faults and specify corresponding protection strategies. The multimodal parameters mentioned in step S1 include: electrical parameters, mechanical parameters, and thermodynamic parameters; The electrical parameters include: power grid harmonic distortion rate (THD), harmonic current data, and voltage signals; the mechanical parameters include: crankshaft torsional amplitude and bearing vibration data; the thermodynamic parameters include: turbine inlet exhaust temperature and cooling water temperature difference. The formula for calculating the dynamic weighting coefficient of the power grid harmonic distortion rate (THD) is as follows: The harmonic distortion rate (THD) of the power grid is represented within a time window. t within variance; α This is the preset mutation sensitivity coefficient; β This is a preset smoothing constant; (t) represents the harmonic distortion rate (THD) of the power grid within the time window. t Dynamic weights within; Indicates the crankshaft amplitude value within the time window t within variance; The dynamic weighting coefficient of the crankshaft torsional amplitude The calculation formula is as follows: ; The formula for calculating the coupling strength index in step S3 is as follows: This is an indicator of coupling strength. THD i Indicates the first i Power grid harmonic distortion rate at each sampling time; THD max This indicates the maximum limit for harmonic distortion rate of the ship's electrical network. A crit This indicates the safety threshold for crankshaft torsional amplitude; A torsion,i Indicates the first i The crankshaft torsional amplitude value at each sampling time; Δ I f,i Indicates the first i Excitation current fluctuation rate at each sampling time; K This represents the excitation current gain coefficient.

2. The intelligent hierarchical diagnosis method for ship electromechanical coupling faults as described in claim 1, characterized in that: The intelligent hierarchical diagnosis in step S4 specifically refers to: When the coupling strength index does not exceed the first preset value, it indicates that there is a potential risk in the ship's power system, and the protection strategy is to enter the early warning state. When the coupling strength index is greater than the first preset value but does not exceed the second preset value, it indicates that the ship's power system has a relatively serious fault. At this time, the protection strategy is to trigger a serious protection action. When the coupling strength index is greater than the second preset value, it indicates that there is a serious fault in the ship's power system. At this time, the protection strategy is to trigger an emergency protection action.

3. A storage medium, characterized in that: The storage medium stores instructions and data to implement the intelligent hierarchical diagnosis method for ship electromechanical coupling faults as described in any one of claims 1 to 2.

4. A smart hierarchical diagnostic device for ship electromechanical coupling faults, characterized in that: include: A processor and a storage medium; the processor loads and executes instructions and data in the storage medium to implement the intelligent hierarchical diagnosis method for ship electromechanical coupling faults as described in any one of claims 1 to 2.

Images