Marine diesel engine damping system and method, medium, product and terminal

Abstract

The invention provides a marine diesel engine damping system and method, a medium, a product and a terminal, the marine diesel engine damping system comprises a positive and negative compensation shaft, a host control system, a control cabinet, a driving cabinet and a brake cabinet, and the control cabinet and the driving cabinet are separately arranged to effectively shield interference of a frequency converter; the vibration signals are analyzed through a singular value decomposition algorithm, the dominant vibration mode is extracted, the corresponding compensation shaft is started according to the space vector and the time vector, and the working parameters of the compensation shaft are set, so that high-precision compensation is performed on each vibration mode, the damping effect is optimized, and the damping efficiency and stability are improved.

Description

Technical Field

[0001] This application relates to the field of marine diesel engine vibration reduction, and in particular to a marine diesel engine vibration reduction system, method, medium, product and terminal. Background Technology

[0002] Marine diesel engines generate a second-order vertical moment during operation. This moment, combined with the ship's natural frequency, causes hull resonance. Excessive hull vibration can lead to fatigue damage to the hull structure, affecting the normal operation of shipboard equipment and instruments, reducing their accuracy, shortening their service life, and in severe cases, causing hull fracture and sinking. Simultaneously, hull vibration also seriously impacts the comfort of crew and passengers, crew work efficiency, and physical health. The main sources of hull vibration are the propeller and diesel engine; therefore, to ensure the safety and comfort of the ship during diesel engine operation, installing a control system compatible with marine shock absorbers is crucial.

[0003] Currently, common vibration dampers for diesel engines on the market include rubber-metal dampers placed between the diesel engine and the ship's hull base, and pneumatic dampers placed inside the cylinder and piston, to reduce vibrations generated during diesel engine operation. However, current measures to reduce vibrations during diesel engine operation are relatively simple and crude, mainly relying on the physical properties of the dampers for passive damping. While this method can meet the vibration reduction needs of diesel engines to a certain extent, its reliability and durability still need further improvement and optimization in long-term operation and complex environments. Furthermore, existing vibration compensation methods generally rely on the physical properties of mechanical structures, such as rubber-metal dampers and pneumatic dampers. These methods are typically passive damping and cannot actively adjust to and adapt to changes in different vibration frequencies. During diesel engine operation, the vibration frequency changes with load, speed, and operating conditions, and existing dampers lack the ability to respond to changes in vibration frequency in real time, often failing to provide precise compensation for different vibration sources. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the purpose of this application is to provide a marine diesel engine vibration damping system, method, medium, product and terminal to solve the above problems.

[0005] To achieve the above and other related objectives, a first aspect of this application provides a marine diesel engine vibration damping system, applied to a diesel engine, comprising: a compensating shaft, including a positive compensating shaft and a negative compensating shaft, respectively fixed to both ends of the crankshaft inside the diesel engine; a main engine control system, used to acquire the speed parameters of the diesel engine and generate a vibration damping enable signal and fuel supply parameters; a control cabinet, electrically connected to the main engine control system, used to receive the speed parameters, vibration damping enable signal and fuel supply parameters of the diesel engine sent by the main engine control system; and the control cabinet is electrically connected to a speed sensor corresponding to the compensating shaft, used to receive the speed parameters of the compensating shaft sent by the speed sensor; a drive cabinet, electrically connected to the control cabinet, used to receive control signals sent by the control cabinet, and drive the positive and negative compensating shafts to rotate in opposite directions based on the control signals; and the drive cabinet feeds back its own drive state parameters to the control cabinet; a brake cabinet, electrically connected to the drive cabinet, used to absorb the kinetic energy of the power unit inside the drive cabinet when the compensating shaft decelerates; the control cabinet and the drive cabinet are separately configured.

[0006] In one embodiment of the first aspect of this application, the control cabinet further includes an HMI display device for displaying the operating status of the marine diesel engine damping system and providing an interactive window to the user.

[0007] In one embodiment of the first aspect of this application, the compensation axis includes a pair of positive compensation axes and a negative compensation axis, or multiple pairs of positive compensation axes and negative compensation axes with different volumes.

[0008] To achieve the above and other related objectives, a second aspect of this application provides a method for vibration reduction of a marine diesel engine, applied to a diesel engine vibration reduction system. The system achieves vibration reduction through a plurality of paired compensation shafts respectively fixed to both ends of the diesel engine crankshaft. The method includes: acquiring vibration signals from different vibration sensors; simultaneously sampling the different vibration signals using the same acquisition card to obtain their corresponding discrete signals; wherein time alignment should be maintained when sampling different vibration signals; constructing a data matrix using the discrete vibration signals corresponding to each sensor; performing singular value decomposition on the data matrix to obtain an energy weight Σ, a spatial pattern matrix U, and a temporal pattern matrix V; wherein the energy weight Σ includes the singular values ​​corresponding to each vibration pattern, the spatial pattern matrix U includes the spatial vector corresponding to each vibration pattern, and the temporal pattern matrix V includes the temporal vector corresponding to each vibration pattern; selecting a plurality of target vibration patterns that contribute significantly to the vibration of the diesel engine based on a preset number of compensation shaft pairs and the singular values ​​corresponding to each vibration pattern; and activating the corresponding compensation shaft and setting the operating parameters of the compensation shaft based on the spatial and temporal vectors corresponding to the target vibration patterns.

[0009] In one embodiment of the second aspect of this application, a method for selecting several target vibration modes that contribute significantly to the vibration of the diesel engine based on a preset number of compensation shaft pairs and the singular values ​​corresponding to each vibration mode includes: obtaining the preset number of compensation shaft pairs N; and selecting the top N vibration modes in descending order of singular values.

[0010] In one embodiment of the second aspect of this application, the method of activating the corresponding compensation axis includes: obtaining the target spatial vector corresponding to each target vibration mode from the spatial mode matrix U; determining the target vibration sensor corresponding to each target spatial vector based on the maximum amplitude component of each target spatial vector; and activating the compensation axis closest to the target vibration sensor and the other compensation axis paired with it.

[0011] In one embodiment of the second aspect of this application, the method for setting the operating parameters of the compensation axis includes: extracting the sign of the real part of the large component of the amplitude of each spatial vector, setting the direction corresponding to the sign as the compensation torque direction of the other compensation axis paired with the compensation axis closest to the target vibration sensor position, and setting the direction after multiplying the sign by (-1) as the compensation torque direction of the compensation axis closest to the target vibration sensor position; obtaining the target time vector corresponding to each target vibration mode from the time mode matrix V; performing a Fourier transform on each time vector and taking the frequency component with the largest amplitude as the main frequency; calculating the phase difference of the time vector relative to the crankshaft top dead center signal; using the phase difference as the compensation signal phase of the other compensation axis paired with the compensation axis closest to the target vibration sensor position, and setting the phase after increasing the phase difference by 180° as the compensation signal phase of the compensation axis closest to the target vibration sensor position.

[0012] To achieve the above and other related objectives, a third aspect of this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in any of the preceding claims.

[0013] To achieve the above and other related objectives, a fourth aspect of this application provides a computer program product comprising computer program code that, when executed on a computer, causes the computer to perform the method described in any of the preceding claims.

[0014] To achieve the above and other related objectives, a fifth aspect of this application provides an electronic terminal, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the method described in any of the preceding claims.

[0015] As described above, this application has the following beneficial effects:

[0016] This application discloses a marine diesel engine vibration damping system, including a positive compensation shaft and a negative compensation shaft respectively fixed to both ends of the crankshaft inside the diesel engine, and a main engine control system, a control cabinet, a drive cabinet, and a brake cabinet for control and status monitoring. The control cabinet and drive cabinet are set up separately, effectively shielding the signal interference problem caused by the high current of the inverter cables. Furthermore, the system has a high degree of integration, enabling a single control system to simultaneously control both the positive and negative compensation shafts, allowing data interaction between the two shafts. The control logic can then coordinate the setting of their starting sequence, resulting in faster following speeds between the two compensation shafts and the main engine control system, and more stable vibration damping. In addition, the control cabinet is equipped with an HMI interface that displays the operating status of the vibration dampers at both ends of the diesel engine, greatly facilitating user operation.

[0017] Furthermore, this application discloses a method for reducing vibration in a marine diesel engine. This method involves collecting vibration signals from different vibration sensors, sampling them to construct a data matrix, and then performing singular value decomposition (SVD) on this data matrix to obtain energy weights Σ, a spatial mode matrix U, and a temporal mode matrix V. Then, based on a preset number of compensation shafts and the singular values ​​corresponding to each vibration mode, several target vibration modes that contribute significantly to the diesel engine vibration are selected. The corresponding compensation shafts are then activated and their operating parameters are set according to the spatial and temporal vectors corresponding to the target vibration modes. Through SVD, the dominant vibration modes contributing the most energy can be automatically extracted from a large number of complex diesel engine vibration signals. These dominant modes correspond to larger singular values, thus accurately identifying the key frequency components in the diesel engine vibration. Furthermore, SVD provides the precise spatiotemporal characteristics of these frequency components, including amplitude, absolute phase, and the direction and plane of vibration. Using these precise spatiotemporal characteristics, the system can effectively perform high-precision compensation for each dominant vibration mode by adjusting the number and operating parameters of the compensation shafts. This refined compensation based on singular value analysis can not only reduce the vibration amplitude of the diesel engine, but also improve the targeting and efficiency of the vibration reduction effect, ensuring that each vibration mode can be properly compensated and controlled, maximizing the vibration reduction performance and reducing the impact on the operation of the diesel engine. Attached Figure Description

[0018] Figure 1 The diagram shown is a structural schematic of a marine diesel engine vibration damping system according to an embodiment of this application.

[0019] Figure 2 The diagram shown is a schematic representation of the positive compensation axis and the negative compensation axis in one embodiment of this application.

[0020] Figure 3 The diagram shown is a structural schematic of the drive cabinet in one embodiment of this application.

[0021] Figure 4 The diagram shown is a structural schematic of the control cabinet in one embodiment of this application.

[0022] Figure 5 The diagram shown is a schematic representation of the brake cabinet in one embodiment of this application.

[0023] Figure 6 The diagram shown is a flowchart illustrating a method for reducing vibration in a marine diesel engine according to an embodiment of this application.

[0024] Figure 7 The diagram shown is a flowchart illustrating a method for activating the corresponding compensation axis in one embodiment of this application.

[0025] Figure 8 The diagram shown is a flowchart illustrating a method for setting the working parameters of a compensation axis according to an embodiment of this application.

[0026] Figure 9 The diagram shown is a structural schematic of an electronic terminal according to an embodiment of this application.

[0027] Component designation explanation

[0028] 1 Positive Compensation Axis

[0029] 2 Negative Compensation Axis

[0030] 3. Frequency converter

[0031] 4 Controller

[0032] 5 HMI display devices

[0033] 6. Braking resistor Detailed Implementation

[0034] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, unless otherwise specified, the following embodiments and features in the embodiments can be combined with each other.

[0035] like Figure 1-5As shown, the first aspect of this application provides a marine diesel engine vibration damping system, applied to a diesel engine, comprising: a compensating shaft, including a positive compensating shaft and a negative compensating shaft, respectively fixed to both ends of the crankshaft inside the diesel engine; a main engine control system, used to collect the speed parameters of the diesel engine and generate a vibration damping enable signal and fuel supply parameters; a control cabinet, electrically connected to the main engine control system, used to receive the speed parameters, vibration damping enable signal and fuel supply parameters of the diesel engine sent by the main engine control system; and the control cabinet is electrically connected to a speed sensor corresponding to the compensating shaft, used to receive the speed parameters of the compensating shaft sent by the speed sensor; a drive cabinet, electrically connected to the control cabinet, used to receive control signals sent by the control cabinet, and drive the positive and negative compensating shafts to rotate in opposite directions based on the control signals; and the drive cabinet feeds back its own drive state parameters to the control cabinet; a brake cabinet, electrically connected to the drive cabinet, used to absorb the kinetic energy of the power unit inside the drive cabinet when the compensating shaft decelerates; the control cabinet and the drive cabinet are separately configured.

[0036] When a marine diesel engine is operating, the crank-connecting rod mechanism generates periodically varying reciprocating inertial forces and rotational inertial torques. The reciprocating inertial force acts on the engine block, causing lateral vibrations perpendicular to the crankshaft axis; the rotational inertial torque causes periodic torsional deformation of the crankshaft, producing torsional vibrations. To simultaneously mitigate these two types of vibrations, this invention employs a paired compensating shaft design, including a positive compensating shaft and a negative compensating shaft. The positive compensating shaft is installed at the crankshaft drive end and rotates in the same direction as the crankshaft; the negative compensating shaft is installed at the crankshaft free end and rotates in the opposite direction. Both compensating shafts are equipped with eccentric masses. Because the positive and negative compensating shafts rotate in opposite directions, their vertical centrifugal force components are opposite in direction. Therefore, by setting the same eccentric mass, the vertical resultant force can be made zero, thereby canceling the lateral vibrations caused by the reciprocating inertial force. Since the horizontal centrifugal force components of the two compensating shafts are in the same direction, their staggered installation positions form a force couple. This force couple generates a compensating torque that is equal in magnitude and opposite in direction to the crankshaft inertial torque. Therefore, torsional vibration cancellation can be achieved through phase matching.

[0037] The main engine control system refers to the marine engine control system (ECS), which can monitor the diesel engine's operating status in real time, collect core parameters such as crankshaft speed, and generate damping enable signals and fuel supply parameters. The damping enable signal is used to trigger the compensation shaft to work, and the fuel supply parameters are used to synchronously optimize the diesel engine's fuel supply.

[0038] The control cabinet acts as a central hub, receiving the compensated shaft speed from the host control system via electrical connection. Based on the compensated shaft speed, it determines the desired motion parameters for the drive cabinet, generates control commands based on these parameters, and sends them to the drive cabinet. Furthermore, the control cabinet can receive real-time data (such as the compensated shaft speed and phase) from the compensated shaft speed sensor and forward this data to the host control system, thereby monitoring the operation of the compensated shaft. Preferably, the control cabinet includes a controller, which implements the aforementioned functions. Because the controller can parse the compensated shaft speed commands from the host control system in real time and synchronously integrate the direct feedback from the compensated shaft speed sensor, thereby calculating the desired motion parameters required by the drive cabinet in real time, this architecture eliminates the data latency between the control cabinet and the drive cabinet in traditional architectures, reducing the command generation time to less than 5ms.

[0039] In a further preferred embodiment, the controller is connected to the main engine (diesel engine) speed sensor of the main engine control system to detect the top dead center (TDC) and bottom dead center (BDC) signals of the main engine, thereby obtaining the speed and phase information of the main engine. Since the controller directly connects to the main engine speed sensor and captures TDC information, it obtains the absolute angular position of the crankshaft in real time. Compared to the traditional method of calculating phase through speed integration, this embodiment can control the dynamic phase difference between the compensation shaft and the crankshaft within ±0.5°, improving the efficiency of vibration damping. Furthermore, when the main engine is suddenly subjected to load (such as when a ship encounters wind and waves), the instantaneous torsional deformation of the crankshaft increases significantly. Traditional speed integration algorithms, which treat the crankshaft as a rigid body, cannot distinguish between actual speed changes and elastic deformation, resulting in compensation lag. This embodiment, however, directly detects the dead center pulses and captures instantaneous torsional distortion based on the distortion analysis of adjacent pulse time intervals, thereby dynamically correcting the phase of the compensation shaft, thus shortening the compensation lag time to within 10ms.

[0040] In a further preferred embodiment, the controller is connected to the speed sensors corresponding to the two compensation shafts to detect the top dead center signal generated when the eccentric mass block of each compensation shaft passes through its geometric highest point, thereby obtaining the accurate speed and phase angle information of the compensation shaft in real time. Since the controller directly captures the original top dead center pulse of the compensation shaft, compared to the traditional method of converting phase through transmission ratio, this embodiment controls the dynamic phase synchronization error between the two compensation shafts within ±0.3° and improves the synthesis accuracy of the reverse torque. Furthermore, when the transmission chain experiences slight wear, the traditional conversion method cannot detect the phase drift caused by mechanical backlash, resulting in a decrease in compensation torque. However, this embodiment directly compares the timing deviation of the top dead center pulses of the two compensation shafts, diagnoses the transmission chain status in real time, and dynamically corrects the phase command, reducing the risk of vibration compensation failure caused by mechanical wear.

[0041] The drive cabinet converts these signals into mechanical kinetic energy, driving the positive and negative compensation shafts to rotate in opposite directions. Simultaneously, it feeds back status parameters such as current and speed to the control cabinet, forming a closed loop. Preferably, the drive cabinet includes two frequency converters connected to the controller to receive control commands. Based on these commands, the frequency converters control the start / stop and torque output of the compensation shaft motors at both ends of the crankshaft. By adjusting the motor speed and torque, the frequency converters can precisely control the motion state of the compensation shafts, further adjusting the vibration damping effect, and feeding back the motor speed and status to the controller in real time, forming a closed-loop control.

[0042] As a safety terminal, the brake cabinet rapidly absorbs the feedback energy from the drive motor during the deceleration of the compensating shaft, preventing system overshoot. This hierarchical cooperation mechanism establishes a safe link from decision-making to execution. Preferably, the brake cabinet includes a braking resistor and a temperature sensor. During motor deceleration or braking, the braking resistor quickly converts the kinetic energy generated by the motor into heat energy, effectively consuming the feedback energy and preventing excessive energy feedback into the system, thus avoiding overshoot or current instability. The temperature sensor is responsible for detecting the operating temperature of the braking resistor. When the temperature of the braking resistor exceeds a set safety value, the temperature sensor promptly detects the change and sends a power-off signal to the system, causing the compensating shaft to decelerate and shut down, achieving thermal protection.

[0043] In one embodiment of the first aspect of this application, the control cabinet further includes an HMI display device for displaying the operating status of the marine diesel engine damping system and providing an interactive window to the user.

[0044] It should be understood that the human-machine interface control panel integrates the full-state monitoring and manual intervention functions of the shock absorption system. In manual mode, the panel can independently control the start and stop of the two compensation shafts, and display the speed of the compensation shafts and the speed of the main unit in real time, as well as the phase following status of the compensation shafts to the speed of the main unit. It can also display the system's fault information and provide fault clearing commands.

[0045] In one embodiment of the first aspect of this application, the compensation axis includes a pair of positive compensation axes and a negative compensation axis, or multiple pairs of positive compensation axes and negative compensation axes with different volumes.

[0046] Since a single pair of compensation axes can only suppress inertial torques of a specific order (such as the second order), while multiple pairs of compensation axes with different volumes can simultaneously cover key harmonic components such as the second, fourth, and sixth orders, more precise compensation for the vibration of the host machine can be achieved, further reducing the intensity of the host machine vibration. For example, small-volume shaft sets use double-frequency rotation speeds to handle high-frequency micro-amplitude vibrations, while large-volume shaft sets focus on canceling low-frequency large-amplitude torques. The principle lies in the difference in volume, which refers to the adjustment of the mass torque of the compensation shaft. The small-volume compensation shaft rotates at a double frequency of the crankshaft, which can suppress the fourth-order and above high-frequency micro-amplitude vibrations. The large-volume compensation shaft rotates at the fundamental frequency of the crankshaft, which can offset the second-order low-frequency large-amplitude torque. Therefore, by rotating the paired compensation shafts with different volumes, the broadband vibration coupling effect can be eliminated through the synthesis of spatial torque. For example, when the main engine is running in the critical speed range (55-65% of the rated speed), the traditional single-pair shaft system cannot take into account the fourth-order resonance peak due to the oversaturation of the second-order compensation torque, resulting in high-frequency flutter of the cabin walls. In this embodiment, the directional high-frequency compensation of the small-volume shaft group attenuates the fourth-order vibration energy by 90%, reducing the cabin noise to below 45dB(A), thereby improving the comfort level of the passenger ship.

[0047] like Figure 6 As shown, to achieve the above and other related objectives, a second aspect of this application provides a method for vibration reduction of a marine diesel engine, applied to a diesel engine vibration reduction system. The system achieves vibration reduction through a plurality of paired compensation shafts respectively fixed to both ends of the diesel engine crankshaft. The method includes: acquiring vibration signals from different vibration sensors; simultaneously sampling the different vibration signals using the same acquisition card to obtain their corresponding discrete signals; wherein time alignment should be maintained when sampling different vibration signals; constructing a data matrix using the discrete vibration signals corresponding to each sensor; performing singular value decomposition on the data matrix to obtain an energy weight Σ, a spatial pattern matrix U, and a temporal pattern matrix V; wherein the energy weight Σ includes the singular values ​​corresponding to each vibration pattern, the spatial pattern matrix U includes the spatial vector corresponding to each vibration pattern, and the temporal pattern matrix V includes the temporal vector corresponding to each vibration pattern; filtering out a plurality of target vibration patterns that contribute significantly to the vibration of the diesel engine based on a preset number of compensation shaft pairs and the singular values ​​corresponding to each vibration pattern; and activating the corresponding compensation shaft and setting the operating parameters of the compensation shaft based on the spatial and temporal vectors corresponding to the target vibration patterns.

[0048] It should be understood that marine diesel engines contain multiple complex and interacting vibration sources, such as the ignition impact of different cylinders, the inertial forces of reciprocating components, the unbalanced forces of rotating components, and gear meshing excitation. The vibration signals generated by these sources are coupled and superimposed in the time and frequency domains, forming a multi-dimensional aliasing effect, making it extremely difficult to directly analyze the dominant vibration source and its spatiotemporal characteristics. The Singular Value Decomposition (SVD) algorithm, through a mathematical decoupling mechanism, decomposes the mixed vibration data matrix collected by multi-channel sensors into three orthogonal bases, namely the left singular vector U, the singular value Σ, and the right singular vector V. The left singular vector represents the spatial distribution pattern of vibration, reflecting the amplitude and phase distribution of specific vibration components on the sensor array (arranged at different positions and directions on the engine), revealing the main direction or plane of vibration force. The singular value represents a scalar value indicating the relative energy or importance of each vibration mode; the larger the singular value, the greater the contribution of the corresponding mode to the overall vibration energy. The right singular vector represents the temporal evolution or frequency pattern of vibration, containing waveform information of specific vibration components changing with time (or crankshaft angle). Essentially, it is a time-domain signal containing precise phase relationships or frequency components corresponding to the main order. Through singular value decomposition (SVD), the dominant vibration mode with the highest energy contribution can be automatically extracted from a large number of complex diesel engine vibration signals.

[0049] These dominant modes correspond to large singular values, enabling accurate identification of key frequency components in diesel engine vibration. Furthermore, singular value decomposition provides precise spatiotemporal characteristics of these frequency components, including amplitude, absolute phase, and the direction and plane of vibration. Using these precise spatiotemporal characteristics, the system can effectively compensate for each dominant vibration mode with high precision by adjusting the number of compensation shafts and their operating parameters. This refined compensation based on singular value analysis not only reduces the vibration amplitude of the diesel engine but also improves the targeting and efficiency of the damping effect, ensuring that each vibration mode receives appropriate compensation and control, maximizing damping performance, and minimizing the impact on diesel engine operation.

[0050] The spatial mode matrix U obtained through singular value decomposition (SVD) can accurately reveal the antisymmetry of vibration modes through the sign of its vector components, such as the vibration characteristics of a 180° phase difference between the two ends of the crankshaft. Paired compensating shafts fixed at both ends of the crankshaft can synchronously generate compensating forces of equal magnitude and opposite direction, perfectly matching this spatial antisymmetry. In contrast, traditional single compensators or dispersed actuators, unable to achieve torque balance, are prone to local overcompensation or undercompensation, weakening the overall damping effect. Furthermore, the main vibration source of a diesel engine will induce antisymmetric bending vibrations in the crankshaft system. Paired compensating shafts, arranged symmetrically, form a torque system that can directly generate a reverse compensating torque, accurately offsetting source torque fluctuations. Other damping devices, such as mass-tuned dampers, can only attenuate vibrations of specific frequencies and cannot dynamically track torque phase changes, thus having limited suppression effects on broadband or variable-condition vibrations. Furthermore, the SVD time pattern matrix V provides phase information accurate to the crankshaft angle, offering data support for compensation phase control. Paired compensation shafts achieve mechanical hard synchronization via a rigid crankshaft, ensuring the compensation force phase difference is strictly maintained at 180°, with phase synchronization error controllable within 0.5°CA. In contrast, electronic synchronization schemes typically have errors exceeding 2°CA. Other damping devices, such as electromagnetic actuators, are prone to compensation force phase mismatch due to control delay differences, significantly reducing vibration cancellation efficiency.

[0051] In one embodiment of the second aspect of this application, a method for selecting several target vibration modes that contribute significantly to the vibration of the diesel engine based on a preset number of compensation shaft pairs and the singular values ​​corresponding to each vibration mode includes: obtaining the preset number of compensation shaft pairs N; and selecting the top N vibration modes in descending order of singular values.

[0052] Because diesel engine vibrations exhibit uneven energy distribution, small vibrations have limited impact on the overall ship, while the main vibration energy is often concentrated in a few key modes. In vibration modes obtained through singular value decomposition (SVD), the contribution of each mode to the overall vibration is directly quantified by its corresponding singular value. Therefore, by selecting the dominant vibration modes that contribute significantly to diesel engine vibration, compensation can be precisely targeted at the most critical modes, thereby optimizing vibration reduction and avoiding unnecessary computation and resource waste. Specifically, in vibration modes obtained through SVD, the larger the singular value corresponding to a vibration mode, the greater its contribution to the overall vibration. Therefore, by selecting the vibration modes corresponding to the top N largest singular values, resources can be concentrated on processing the most important vibration modes, achieving efficient and precise vibration reduction.

[0053] For example, suppose that after singular value decomposition, five vibration modes are obtained: vibration mode 1, vibration mode 2, vibration mode 3, vibration mode 4, and vibration mode 5, with corresponding singular values ​​of 0.84, 0.15, 0.1, 0.05, and 0.03, respectively. Assuming N is 2, the vibration modes with larger singular values ​​of 0.84 and 0.15, namely vibration mode 1 and vibration mode 2, are selected as the target vibration modes.

[0054] like Figure 7 As shown, in one embodiment of the second aspect of this application, the method of activating the corresponding compensation axis includes: obtaining the target spatial vector corresponding to each target vibration mode from the spatial mode matrix U; determining the target vibration sensor corresponding to each target spatial vector based on the maximum amplitude component of each target spatial vector; and activating the compensation axis closest to the target vibration sensor and the other compensation axis paired with it.

[0055] By obtaining the target spatial vector corresponding to each target vibration mode from the spatial mode matrix and determining the target vibration sensor based on the maximum amplitude component of this spatial vector, the compensation system can focus on the most critical part of the vibration, ensuring that the compensation axis aligns with the main direction of action of the vibration mode, thus achieving more effective vibration compensation. Furthermore, by selecting the target vibration sensor based on the maximum amplitude component of each target spatial vector and activating the compensation axis closest to the target vibration sensor, unnecessary resource consumption can be effectively reduced, improving not only the efficiency of the compensation axis but also reducing the system's complexity and computational burden.

[0056] For example, suppose that for vibration mode 1, the components of the spatial vector are U1 = [0.5, 0.2, 0.3, 0.1]. This means that the intensity of vibration mode 1 is 0.5 at vibration sensor 1, 0.2 at vibration sensor 2, 0.3 at vibration sensor 3, and 0.1 at vibration sensor 4. Since the maximum component of the spatial vector is 0.5, the compensation axis closest to vibration sensor 1 and its paired compensation axis are activated for vibration compensation.

[0057] like Figure 8As shown, in one embodiment of the second aspect of this application, the method for setting the working parameters of the compensation axis includes: extracting the sign of the real part of the large component of the amplitude of each spatial vector, setting the direction corresponding to the sign as the compensation torque direction of the other compensation axis paired with the compensation axis closest to the target vibration sensor position, and setting the direction after multiplying the sign by (-1) as the compensation torque direction of the compensation axis closest to the target vibration sensor position; obtaining the target time vector corresponding to each target vibration mode from the time mode matrix V; performing a Fourier transform on each time vector and taking the frequency component with the largest amplitude as the main frequency; calculating the phase difference of the time vector relative to the crankshaft top dead center signal; using the phase difference as the compensation signal phase of the other compensation axis paired with the compensation axis closest to the target vibration sensor position, and setting the phase after increasing the phase difference by 180° as the compensation signal phase of the compensation axis closest to the target vibration sensor position.

[0058] By extracting the sign of the real part of the largest component of each spatial vector, the direction of the compensation torque of the compensation axis can be determined. This method ensures that the direction of the torque of the compensation axis is consistent with the main direction of the vibration mode, thus making the compensation system more efficient. The design of paired compensation axes ensures multi-dimensional accuracy of vibration compensation, and this precise directional control avoids resource waste and improves the damping effect. By extracting the target time vector from the time mode matrix and performing a Fourier transform, the system can determine the main frequency of each vibration mode and adjust the phase of the compensation signal based on the phase difference. This means that the system can adapt to different working conditions and vibration characteristics, ensuring that each compensation axis provides compensation torque at the correct time, thereby reducing vibration more accurately. By adjusting the phase of the compensation signal of the compensation axis to precisely match the timing of the target vibration mode, the resonance phenomenon of vibration can be effectively avoided. This method ensures that the phases of the paired compensation axes are exactly complementary by increasing the phase difference by 180°, maximizing the compensation effect and reducing unnecessary vibrations that the system may generate. This method can adjust the working parameters of the compensation axis in real time according to the specific frequency and phase characteristics of each vibration mode. In this way, the system can adapt to different working environments and improve the stability and reliability of the damping effect.

[0059] For example, suppose the spatial vector of vibration mode 1 is U1 = [0.4, 0.3, 0.5, 0.2]. The four elements from left to right represent the intensity of the vibration mode on vibration sensors 1-4. Select vibration sensor 3 corresponding to the maximum amplitude component 0.5, extract the real part of the maximum component 0.5, which is a positive value. Then, it is said that the direction of the compensation torque should be consistent with the rotation direction of the crankshaft. Set the torque direction of the compensation shaft that is closest to the vibration sensor 3 to be opposite to the rotation direction of the crankshaft.

[0060] Assuming the time vector is V1 = [1.2, -0.8, 0.5, 0.3], after performing a Fourier transform on this vector, the amplitudes of the frequency components are as follows: frequency 1 has an amplitude of 1.8, frequency 2 has an amplitude of 0.5, and frequency 3 has an amplitude of 0.2. The frequency component with the largest amplitude, frequency 1, is selected as the dominant frequency. Assuming the phase corresponding to the dominant frequency is 30°, the phase of the crankshaft dead center signal is 60°, so the phase difference is 30° - 60° = -30°. Therefore, the phase of the compensation signal of the other compensation axis paired with the compensation axis closest to the vibration sensor 3 is set to -30°, while the phase of the compensation signal of the compensation axis closest to the target vibration sensor is set to -30° + 180° = 150°.

[0061] To achieve the above and other related objectives, a third aspect of this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in any of the preceding claims.

[0062] To achieve the above and other related objectives, a fourth aspect of this application provides a computer program product comprising computer program code that, when executed on a computer, causes the computer to perform the method described in any of the preceding claims.

[0063] like Figure 9 As shown, to achieve the above and other related objectives, a fifth aspect of this application provides an electronic terminal, including: at least one processor 901, a memory 902, at least one network interface 903, and a user interface 905. The various components in the device are coupled together via a bus system 904. It is understood that the bus system 904 is used to enable communication between these components. In addition to a data bus, the bus system 904 also includes a power bus, a control bus, and a status signal bus.

[0064] The user interface 905 may include a monitor, keyboard, mouse, trackball, clicker, button, touchpad, or touch screen.

[0065] It is understood that memory 902 can be volatile memory or non-volatile memory, or both. Non-volatile memory can be read-only memory (ROM) or programmable read-only memory (PROM), used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as static random access memory (SRAM) and synchronous static random access memory (SSRAM). The memories described in the embodiments of this invention are intended to include, but are not limited to, these and any other suitable categories of memory.

[0066] In this embodiment of the invention, the memory 902 is used to store various types of data to support the operation of the electronic terminal 900. Examples of this data include: any executable program for operation on the electronic terminal 900, such as the operating system 9021 and application programs 9022; the operating system 9021 contains various system programs, such as the framework layer, core library layer, driver layer, etc., for implementing various basic services and handling hardware-based tasks. The application program 9022 may contain various applications, such as a media player, browser, etc., for implementing various application services. The methods provided in this embodiment of the invention can be included in the application program 9022.

[0067] The methods disclosed in the above embodiments of the present invention can be applied to or implemented by processor 901. Processor 901 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the integrated logic circuit of the hardware in processor 901 or by instructions in software form. The processor 901 may be a general-purpose processor, a digital signal processor (DSP), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Processor 901 can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. General-purpose processor 901 may be a microprocessor or any conventional processor, etc. The steps of the accessory optimization method provided in the embodiments of the present invention can be directly reflected as being executed by a hardware decoding processor, or being executed by a combination of hardware and software modules in the decoding processor. The software module may be located in a storage medium, which is located in memory. The processor reads the information in the memory and combines it with its hardware to complete the steps of the aforementioned method.

[0068] In an exemplary embodiment, the electronic terminal 900 may be used by one or more application-specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), or complex programmable logic devices (CPLDs) to execute the aforementioned method.

[0069] It should be understood that in the embodiments of this application, terms such as "first" and "second" are used to distinguish identical or similar items with substantially the same function and effect. For example, "first XX" and "second XX" are merely to distinguish different XXs and do not limit their order. Those skilled in the art will understand that terms such as "first" and "second" do not limit the quantity or execution order, and that terms such as "first" and "second" do not necessarily imply that they are different.

[0070] In this application, the terms "exemplary" or "for example" indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0071] In this application embodiment, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0072] The terms “component,” “module,” “system,” etc., used in this specification are used to refer to computer-related entities, hardware, firmware, combinations of hardware and software, software, or software in execution. For example, a component can be, but is not limited to, a process running on a processor, a processor, an object, an executable file, an execution thread, a program, and / or a computer. As illustrated, applications running on computing devices and computing devices can both be components. One or more components may reside in a process and / or an execution thread, and components may be located on a single computer and / or distributed among two or more computers. Furthermore, these components can be executed from various computer-readable media on which various data structures are stored. Components can communicate, for example, via local and / or remote processes based on signals having one or more data packets (e.g., data from two components interacting with another component between a local system, a distributed system, and / or a network, such as the Internet interacting with other systems via signals).

[0073] Those skilled in the art will recognize that the various illustrative logical blocks and steps described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this application.

[0074] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0075] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0076] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0077] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0078] In the above embodiments, the functions of each functional unit can be implemented entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. A computer program product includes one or more computer instructions (programs). When the computer program instructions (programs) are loaded and executed on a computer, all or part of the flow or function according to the embodiments of this application is generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. Computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., high-density digital video discs, DVDs), or semiconductor media (e.g., solid-state disks, SSDs, etc.).

[0079] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0080] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0081] In summary, this application effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0082] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. A vibration damping system for a marine diesel engine, applied to a diesel engine, characterized in that, include: The compensation shaft, including a positive compensation shaft and a negative compensation shaft, is fixed to both ends of the crankshaft inside the diesel engine, respectively; The main control system is used to collect the speed parameters of the diesel engine and generate damping enable signals and fuel supply parameters; The control cabinet is electrically connected to the main control system to receive the diesel engine speed parameters, damping enable signal and fuel supply parameters sent by the main control system; and the control cabinet is electrically connected to the speed sensor corresponding to the compensation shaft to receive the speed parameters of the compensation shaft sent by the speed sensor. The drive cabinet is electrically connected to the control cabinet and is used to receive control signals sent by the control cabinet and drive the positive compensation shaft and the negative compensation shaft to rotate in opposite directions based on the control signals. Furthermore, the drive cabinet feeds back its own drive status parameters to the control cabinet; The brake cabinet is electrically connected to the drive cabinet and is used to absorb the kinetic energy of the power unit in the drive cabinet when the compensation shaft decelerates. The control cabinet and drive cabinet are set up separately.

2. The marine diesel engine vibration damping system according to claim 1, characterized in that, The control cabinet also includes an HMI display device to display the operating status of the marine diesel engine vibration damping system and provide an interactive window to the user.

3. The marine diesel engine vibration damping system according to claim 1, characterized in that, The compensation axis includes a pair of positive compensation axes and a negative compensation axis, or multiple pairs of positive compensation axes and negative compensation axes with different volumes.

4. A method for damping vibrations in a marine diesel engine, applied to a diesel engine damping system, characterized in that, The system achieves vibration reduction through a number of pairs of compensating shafts respectively fixed to both ends of the diesel engine crankshaft, and the method includes: Acquire vibration signals from different vibration sensors; The same data acquisition card is used to sample the different vibration signals simultaneously to obtain their corresponding discrete signals; time alignment should be maintained when sampling different vibration signals. A data matrix is ​​constructed using the discrete vibration signals corresponding to each sensor; The data matrix is ​​subjected to singular value decomposition to obtain energy weights Σ, spatial pattern matrix U, and temporal pattern matrix V; wherein, the energy weights Σ include the singular values ​​corresponding to each vibration mode, the spatial pattern matrix U includes the spatial vector corresponding to each vibration mode, and the temporal pattern matrix V includes the temporal vector corresponding to each vibration mode. Based on the preset number of compensation shaft pairs and the singular value corresponding to each vibration mode, several target vibration modes that contribute significantly to the vibration of the diesel engine are selected. The corresponding compensation axis is activated and its operating parameters are set based on the spatial and temporal vectors corresponding to the target vibration mode.

5. A vibration reduction method for a marine diesel engine according to claim 4, characterized in that, The method for selecting several target vibration modes that contribute significantly to the vibration of the diesel engine based on a preset number of compensation shaft pairs and the singular values ​​corresponding to each vibration mode includes: obtaining the preset number of compensation shaft pairs N; and selecting the top N vibration modes in descending order of singular values.

6. The vibration reduction method for a marine diesel engine according to claim 4, characterized in that, The method for activating the corresponding compensation axis includes: Obtain the target spatial vector corresponding to each target vibration mode from the spatial mode matrix U; The target vibration sensor is determined based on the maximum amplitude component of each target spatial vector; Activate the compensation axis closest to the target vibration sensor and the other compensation axis that is paired with it.

7. A vibration reduction method for a marine diesel engine according to claim 6, characterized in that, The method for setting the operating parameters of the compensation axis includes: Extract the sign of the real part of the large component of the magnitude of each spatial vector, set the direction corresponding to the sign as the direction of the compensation torque of the other compensation axis paired with the compensation axis closest to the target vibration sensor position, and set the direction after multiplying the sign by (-1) as the direction of the compensation torque of the compensation axis closest to the target vibration sensor position. Obtain the target time vector corresponding to each target vibration mode from the time pattern matrix V; After performing a Fourier transform on each time vector, the frequency component with the largest amplitude is taken as the dominant frequency. Calculate the phase difference of the time vector relative to the crankshaft top dead center signal; The phase difference is used as the compensation signal phase of the other compensation axis paired with the compensation axis closest to the target vibration sensor position, and the phase after increasing the phase difference by 180° is set as the compensation signal phase of the compensation axis closest to the target vibration sensor position.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 4-7.

9. A computer program product, characterized in that, The computer program product includes computer program code that, when run on a computer, causes the computer to perform the method as described in any one of claims 4-7.

10. An electronic terminal, comprising a memory, a processor, and a computer program stored in the memory, characterized in that, The processor executes the computer program to implement the method of any one of claims 4-7.

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