A passive-active integrated damping device and damping method for air-powered boats

Abstract

The application discloses a kind of active and passive integrated vibration damping device and damping method for air power boat, it is related to the technical field of vibration damping and noise reduction, active part, passive part is integrated in same shell, respectively located in device upper half, lower half;Active part includes piezoelectric sensor, center rod, magnetic core distributed from inside to outside along center rod, permanent magnet, coil, yoke, center rod reciprocates along vertical direction;Passive part includes elastic element, guide rod, lower coil, armature, damping element, elastic element is located in the periphery of center rod, damping element is located in the bottom of device, armature is fixed in the bottom of center rod, lower coil is symmetrically distributed in the two sides of center rod, position corresponds with the position of armature, armature and lower coil form electromagnetic cooperation gap.The application can rely on spring and damping element to passively isolate small amplitude vibration, and can rely on electromagnetic force to actively cancel wide-band vibration, to realize efficient and stable vibration damping under wide-band, multiple working conditions.

Description

Technical Field

[0001] This invention relates to the field of vibration reduction and noise reduction technology, and in particular to an integrated active and passive vibration reduction device and method for aerodynamic boats. Background Technology

[0002] Aerodynamic boats typically rely on high-powered engines to drive propellers and generate thrust. During engine operation, significant periodic vibrations, impact vibrations, and structurally transmitted vibrations are produced. These vibrations are transmitted outward through the engine mounts, supports, and hull structure, causing hull vibration, structural noise, and aerodynamic noise, affecting operational stability, passenger comfort, and ambient noise levels.

[0003] Among existing vibration reduction solutions, purely passive vibration reduction (such as rubber pads, springs, damping pads, or vibration damping supports) has the advantages of simple structure, high reliability, and low cost. However, its vibration reduction performance is limited by material properties and structural parameters, making it difficult to adjust in real time for engine speed changes, low-frequency vibrations, resonance conditions, and complex conditions. In particular, its ability to suppress large-amplitude impact vibrations and low-frequency strong vibrations is limited. Purely active vibration reduction solutions (such as electromagnetic devices) can output controllable forces in real time, but they completely lose their vibration reduction capability when power is cut off or the control system fails, and their energy consumption is high when powered on for extended periods.

[0004] Furthermore, existing electromagnetic active vibration damping devices suffer from significant coil overheating during prolonged high-load operation. High temperatures increase coil resistance and degrade permanent magnet performance, severely impacting the device's output efficiency and operational stability. Additionally, traditional devices lack direct monitoring of the stress state at the top, making it difficult to optimize vibration damping control strategies based on actual load conditions. Summary of the Invention

[0005] In order to overcome the above-mentioned problems in the prior art, the present invention proposes an active and passive integrated vibration reduction device and vibration reduction method for aerodynamic boats.

[0006] The technical solution adopted by the present invention to solve its technical problem is: an active and passive integrated vibration reduction device for aerodynamic boats, comprising an active part and a passive part, wherein the active part is located in the upper half of the device and the passive part is located in the lower half of the device, the active part and the passive part are integrated in the same housing, the active part is used to reduce vibration under conditions of large impact or low frequency strong vibration, and the passive part is used to reduce vibration under conditions of small amplitude vibration. The active part includes a piezoelectric sensor for real-time detection of the pressure condition of the device, a vibration detection unit for real-time detection of vibration, a central rod running through the entire device, and a magnetic core, permanent magnet, coil, and yoke distributed from the inside to the outside along the central rod. The permanent magnet, coil, magnetic core, and yoke together constitute an electromagnetic drive circuit, and the central rod moves up and down reciprocally in the vertical direction. The passive component includes an elastic element, a guide rod, a lower coil, an armature, and a damping element. The elastic element is located around the center rod, and the damping element is located at the end of the elastic element away from the active component. The armature is fixed at the end of the center rod away from the active component. The lower coil is symmetrically distributed on both sides of the center rod, with its position corresponding to the position of the armature. The armature and the lower coil form an electromagnetic engagement gap. When the armature and the lower coil are energized, they interact to generate an electromagnetic damping force or driving force acting on the center rod.

[0007] The aforementioned active and passive integrated vibration damping device for aerodynamic boats includes a coil comprising a main coil and an auxiliary coil, which are arranged symmetrically about the axis of a central rod. The number of turns of the main coil differs from the number of turns of the auxiliary coil, so that the main coil and the auxiliary coil are adapted to different frequency bands.

[0008] The aforementioned active and passive integrated vibration damping device for aerodynamic boats includes a main coil with 300-500 turns and an auxiliary coil with 100-200 turns.

[0009] The aforementioned active and passive integrated vibration damping device for aerodynamic boats further includes a heat-conducting structure in the active part. The heat-conducting structure is installed on the outside of the yoke and close to the outer periphery of the coil to conduct away the heat generated by the coil during operation.

[0010] The aforementioned active and passive integrated vibration damping device for aerodynamic boats includes a heat-conducting structure comprising a heat-conducting iron sheet and a water-cooling pipe. The heat-conducting iron sheet is wrapped around the outside of the yoke and closely attached to the outer periphery of the coil, used to conduct the heat generated by the coil to the water-cooling pipe. The water-cooling pipe is arranged close to the outer wall of the heat-conducting iron sheet, and the pipe is led out from the top of the device through a hole and connected to an external small water pump. The external small water pump drives the coolant in the pipe to circulate between the inside and outside of the device. After the coolant is cooled outside the device, it flows back to the inside of the device, forming a closed internal circulation water-cooling system.

[0011] The aforementioned active and passive integrated vibration damping device for aerodynamic boats includes a guide sleeve on the outer side of the central rod corresponding to the active part, and a planar flexible elastic element between the end of the central rod away from the passive part and the shell. The planar flexible elastic element is used to radially straighten the central rod and provide axial elastic reset.

[0012] A method for integrated active and passive vibration reduction for aerodynamic boats, based on the aforementioned integrated active and passive vibration reduction device for aerodynamic boats, specifically includes: The piezoelectric sensor detects the pressure applied to the device in real time and transmits the resulting pressure signal to the control unit. The control unit converts the pressure signal into a real-time pressure value and compares it with a preset pressure threshold. When the real-time pressure value exceeds the preset pressure threshold or the pressure fluctuation amplitude exceeds the preset fluctuation threshold, the control unit determines that the device has entered a loaded working state and controls the main coil and / or auxiliary coil of the active part to be energized. When the real-time pressure value is lower than the preset pressure threshold and continues for more than a preset time, the control unit determines that the device is in a low-load state and controls the main coil and auxiliary coil to be de-energized or enter a low-power standby state. When the equipment being vibration damped is under small-amplitude vibration conditions, the vibration energy is transmitted through the central rod to the elastic and damping elements of the passive part. The elastic deformation of the elastic element buffers the vibration, and the damping element dissipates the vibration energy through viscous damping, thus achieving passive vibration isolation. When the equipment being damped is subjected to large impact or low-frequency strong vibration, a controllable current is supplied to the main coil of the active part, which drives the central rod to output a reverse controllable force through electromagnetic effect, thereby offsetting or weakening the outward transmission of vibration; when the equipment being damped exhibits high-frequency vibration components, a controllable current is supplied to the auxiliary coil to help enhance the high-frequency vibration suppression effect.

[0013] The aforementioned active-passive integrated vibration reduction method for aerodynamic boats distinguishes between small-amplitude vibration conditions, large-amplitude impact or low-frequency strong vibration conditions, and high-frequency vibration components by the control unit based on the detection signals from the vibration detection unit and the piezoelectric sensor: when the vibration detection unit detects a vibration displacement amplitude less than 0.5 mm and a main vibration frequency higher than 30 Hz, it is determined to be a small-amplitude vibration condition; when the vibration displacement amplitude is greater than 2 mm or the peak vibration acceleration exceeds 5 g and the main vibration frequency is lower than 20 Hz, it is determined to be a large-amplitude impact or low-frequency strong vibration condition; when the amplitude of the component with a frequency higher than 50 Hz in the vibration signal accounts for more than 20% of the total amplitude, it is determined that a high-frequency vibration component exists.

[0014] The aforementioned active-passive integrated vibration reduction method for aerodynamic boats, wherein the energizing current of the main coil and auxiliary coil is determined in real time by the control unit based on the pressure signal detected by the piezoelectric sensor and the vibration signal detected by the vibration detection unit: Main coil current... Auxiliary coil current ,in , These are the required reverse forces for the low-frequency and high-frequency bands, calculated by the control unit, respectively. , These are the force constants of the main coil and the auxiliary coil, respectively.

[0015] The beneficial effects of this invention are that it integrates an electromagnetic active vibration damping structure and a spring-damped passive vibration damping structure into the same housing, forming a vertically axially symmetrical cylindrical structure. A top-load-bearing iron plate replaces the traditional mounting flange, bearing the upper pressure and protecting the internal structure. The upper coil is divided into a main coil (300-500 turns) and an auxiliary coil (100-200 turns) to handle low-frequency and high-frequency vibrations respectively. A water-cooling system (thermal conductive iron sheet combined with water-cooled pipes and an external circulating water pump) solves the coil overheating problem. A piezoelectric sensor enables real-time detection of the top force. This allows a single device to passively isolate small-amplitude vibrations using springs and damping elements, and actively cancel wide-band vibrations using electromagnetic force, while also possessing efficient heat dissipation and load sensing capabilities, thus achieving efficient and stable vibration damping across a wide frequency range and various operating conditions. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the present invention.

[0017] Among them, 1. Top load-bearing iron plate, 2. Piezoelectric sensor, 3. Central rod, 4. Permanent magnet, 5. Coil, 6. Water-cooled pipe, 7. Steel core, 8. Guide sleeve, 9. Planar flexible spring, 10. Spring seat, 11. Armature, 12. Lower coil, 13. Air gap, 14. Helical compression spring, 15. Base. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] This invention discloses an integrated active and passive vibration damping device for aerodynamic boats, such as... Figure 1 As shown, the overall structure is a vertically symmetrical cylindrical structure, consisting of two main functional modules: an active part and a passive part. The active part is located in the upper half of the device, and the passive part is located in the lower half of the device. The two are integrated into the same housing.

[0020] The active component includes: a top load-bearing iron plate 1, a piezoelectric sensor 2, a planar flexible spring 9, a central rod 3, a permanent magnet 4, a coil 5, a steel core 7, a yoke, a heat-conducting iron sheet, a water-cooling pipe 6, and a guide sleeve 8. In this embodiment, the coil includes a main coil and an auxiliary coil.

[0021] The top load-bearing plate 1 is located at the very top of the device, serving to withstand upper pressure, protect the internal structure of the device, and provide an upper bearing surface for external installation. Compared with traditional mounting flange structures, the top load-bearing plate directly bears the load from the vibration-damped equipment or the upper base, uniformly transmitting the force to the shell, simplifying the top connection structure, and enhancing the top's compressive strength.

[0022] The piezoelectric sensor 2 is installed below the top load-bearing iron plate and is in close contact with the lower surface of the top load-bearing iron plate. When the top load-bearing iron plate is subjected to the upper load pressure, the piezoelectric sensor generates an electrical signal corresponding to the pressure magnitude. This signal is transmitted to the external control unit through a lead wire to monitor the stress state of the top of the device in real time and to provide load parameter basis for the vibration reduction control strategy.

[0023] The planar flexible spring 9 is located on the inner side of the top force-bearing iron plate. It is a thin-plate flexible elastic element used to radially straighten the central rod and provide a small-amplitude axial elastic reset to restrain the lateral sway of the rod.

[0024] The central rod 3 runs through the entire length of the device and is the core output component for transmitting the active force and passive elastic force of the device to the outside. It can move up and down in the vertical direction to output vibration reduction force.

[0025] The permanent magnet 4 is arranged inside the main coil and auxiliary coil and outside the steel core, and together with the main coil and auxiliary coil, it forms an electromagnetic drive circuit.

[0026] The main coil and auxiliary coil are symmetrically arranged windings, both located in the upper electromagnetic drive section of the device. The main coil has 300-500 turns, generating a strong electromagnetic driving force when energized, primarily used to handle low-frequency vibrations and large-amplitude impact vibrations. The auxiliary coil has 100-200 turns, providing a fast response and mainly used to assist in handling high-frequency vibration components. The main coil and auxiliary coil can be independently energized and controlled according to the actual vibration conditions, or they can be energized simultaneously for coordinated operation. The main coil, auxiliary coil, permanent magnet, and steel core work together to generate electromagnetic driving force, driving the central rod up and down to achieve wide-band active vibration damping output.

[0027] The steel core 7 is located around the center rod and is a magnetic core structure used to gather the magnetic field generated by the main coil and the auxiliary coil, thereby improving the electromagnetic actuation efficiency.

[0028] The yoke is wrapped around the outside of the main coil and auxiliary coil, forming a magnetically conductive frame to close the magnetic circuit and reduce magnetic field leakage.

[0029] The heat-conducting iron sheet is wrapped around the outside of the yoke and closely attached to the outer area of ​​the main coil and auxiliary coil. It is made of a metal material with a high thermal conductivity and is used to quickly conduct the heat generated by the coil when it is energized to the water-cooling pipe.

[0030] The water-cooled pipes 6 are arranged close to the outer wall of the heat-conducting iron sheet, using a spiral or serpentine coil method to increase the contact area with the heat-conducting iron sheet and improve heat exchange efficiency. Both ends of the water-cooled pipes extend from dedicated through-holes at the top of the device, connecting to the outlet and return ports of an external small water pump, respectively. The external small water pump drives the coolant (such as water, ethylene glycol aqueous solution, etc.) within the pipes to circulate in a closed loop: as the coolant flows through the water-cooled pipes inside the device, it absorbs heat conducted by the heat-conducting iron sheet. The heated coolant is then pumped to the outside of the device, where it dissipates heat to the environment through natural heat dissipation or an external radiator. The cooled coolant then flows back into the device to continue absorbing heat, forming a closed-loop internal circulation water-cooling system. This system effectively reduces the internal temperature of the device, preventing increased resistance and insulation aging of the main and auxiliary coils due to high temperatures, ensuring the permanent magnet operates within a suitable temperature range, and thus ensuring the device's efficiency and reliability under long-term high-load conditions.

[0031] The guide sleeve 8 is a bushing structure located inside the housing, used to provide sliding guidance for the central rod, ensuring that the rod only moves axially and limiting radial offset.

[0032] The passive component includes: a helical compression spring 14, a spring seat 10, a guide sleeve 8, a damping element (not shown in the figure), an armature 11, an air gap 13, a base 15, and an optional lower coil 12. In this embodiment, the armature is a plunger or a moving iron core, and the damping element is a damping pad or a rubber vibration isolator.

[0033] The helical compression spring is the core elastic element for passive vibration reduction. It adopts a large cylindrical helical compression spring structure, bears axial load, and relies on spring deformation to buffer small vibration impacts.

[0034] The spring seat is located at both ends of the helical compression spring and serves as a support base to evenly transmit the spring force to the housing and the central guide structure.

[0035] The guide sleeve, in conjunction with the center rod and spring seat, ensures that the helical compression spring remains centered during compression, preventing the helical compression spring from becoming unstable under pressure and from lateral deflection.

[0036] The damping pad / rubber isolator is located at the lower end of the helical compression spring to provide viscous damping energy dissipation, converting vibrational mechanical energy into heat dissipation, and suppressing the reciprocating oscillation of the helical compression spring.

[0037] The lower coil is an optional structure, arranged symmetrically on the left and right sides of the bottom of the passive section, used to extend the lower electromagnetic auxiliary actuation and vibration damping capabilities.

[0038] The plunger / moving iron core is fixed at the lowest end of the central rod and is an iron core component used to form an electromagnetic cooperation structure with the lower coil.

[0039] The air gap is a tiny gap between the plunger / moving iron core and the inner side of the lower coil, which is a necessary magnetic circuit gap for electromagnetic drive.

[0040] The base is located at the bottom of the device and has fastening bolts. It is used to close the lower structure and serves as the mounting base for the lower part of the device.

[0041] The core innovation of this invention lies in achieving active-passive vibration reduction through electromagnetic-mechanical coupling, and forming a multi-physics collaborative working system through dual-coil frequency division design, water cooling, and piezoelectric detection. The working principles and coupling relationships of each subsystem of this device are quantitatively described below using mathematical models based on electromagnetics, dynamics, thermodynamics, and the piezoelectric effect.

[0042] I. Electromagnetic Driving Force Model The core driving force for the active vibration reduction of this device comes from the Ampere force (Lorentz force) experienced by the current-carrying coil in the magnetic field of the permanent magnet. According to the basic principles of electromagnetism, the force experienced by a current-carrying conductor of length l in a magnetic field with magnetic induction intensity B is: ; In the formula: electromagnetic driving force ( ), The number of coil turns. air gap magnetic induction intensity ( ), i is the coil current ( ), The effective conductor length of a single-turn coil ( ).

[0043] The main coil (N1 = 300~500 turns) and auxiliary coil (N2 = 100~200 turns) in this invention have the following output electromagnetic driving forces: ; Under the same current and magnetic field conditions, since N1 > N2, the main coil can generate approximately 2 to 5 times the electromagnetic driving force of the auxiliary coil. Therefore, the main coil is suitable for low-frequency vibration and shock vibration suppression scenarios requiring significant force output. Simultaneously, a force constant is defined. Then the basic equation of electromagnetic driving force can be simplified to: The force constant directly reflects the efficiency with which the coil converts current into mechanical force. (Main coil force constant) Significantly greater than the force constant of the auxiliary coil This parameter difference provides the physical basis for the dual-coil frequency division control of the present invention.

[0044] II. Magnetic Circuit Analysis and Magnetic Permeability Optimization In this device, the permanent magnet, steel core, yoke, and air gap together form a closed magnetic circuit. According to Ohm's law for magnetic circuits, the relationship between the magnetic flux, magnetomotive force, and magnetic reluctance in the magnetic circuit is as follows: In the formula: denoted as magnetic flux (Wb). It is a magnetomotive force. The total magnetic reluctance of the magnetic circuit ( Magnetic resistance It consists of several magnetic circuit segments connected in series: in, For the magnetic reluctance of the core segment, The magnetic reluctance of the yoke section. For the air gap section magnetic reluctance, The magnetic reluctance is for the permanent magnet segment.

[0045] The formula for calculating the magnetic reluctance of each uniform cross-section magnetic circuit is as follows:

[0046] In the formula: is the length of the magnetic track section (m). The permeability of free space, The relative permeability of the material, The cross-sectional area of ​​the magnetic circuit section ( ).

[0047] In this invention, the steel core and yoke are made of high-permeability silicon steel. Its magnetic reluctance is much smaller than that of the air gap magnetic reluctance ( Therefore, the total magnetic reluctance of the magnetic circuit is mainly determined by the air gap. The closed yoke structure confines the magnetic lines of force within the magnetically conductive material, controlling the flux leakage rate to below 5%. Compared to an open magnetic circuit (with a leakage rate of 30%~50%), the effective air gap magnetic induction intensity B can be increased by approximately 40%~90%. The magnetic induction intensity in the air gap is: ,in This represents the effective cross-sectional area of ​​the air gap.

[0048] High air gap magnetic induction intensity B directly increases the force constant This allows the same coil current to generate a larger electromagnetic driving force. This is the fundamental advantage of the closed yoke ferromagnetic circuit design used in this device.

[0049] III. Electromagnetic-Mechanical Coupling Dynamic Model The core moving component of the device (the central rod and the mass of the moving part connected to it) moves under the combined action of external vibration force, passive elastic-damping force, and active electromagnetic force. Its single-degree-of-freedom dynamic equation in the vertical direction is:

[0050] Where: m is the equivalent kinematic mass (kg), and c is the equivalent viscous damping coefficient (kg). ), k is the equivalent spring stiffness ( ), , , These are displacement, velocity, and acceleration, respectively. The external excitation force (N) is the force exerted. It is an active electromagnetic driving force (N).

[0051] The active electromagnetic driving force is composed of the superposition of the electromagnetic forces of the main coil and the auxiliary coil: ; The electromagnetic force of the main coil, The electromagnetic force is used to assist the coil.

[0052] Substituting the active force composition equation into the system dynamics equation, we obtain the complete electromagnetic-mechanical coupling dynamics equation:

[0053] The electromagnetic-mechanical coupling dynamic equations reveal the core working principle of this invention: passive vibration reduction term ( ) provides basic passive vibration isolation and energy dissipation, active electromagnetic force term ( Adjustments are made in real time according to the vibration state. When the active force and the external excitation force satisfy... When the right side of the equation approaches zero, the central rod produces almost no acceleration response, and the vibration is effectively canceled out.

[0054] IV. Electrical Analysis of Main / Auxiliary Coil Frequency Division Control As the core component of an electromagnetic actuator, the coil's electrical characteristics—especially its inductance and time constant—directly determine its response to vibrations of different frequencies. The equivalent circuit equation of the coil is:

[0055] In the formula: L is the driving voltage (V), L is the coil inductance (H), and R is the coil DC resistance (V). ), This is the back electromotive force (V). The back electromotive force is caused by the velocity of the central rod.

[0056] The back electromotive force equation embodies the two-way coupling between electromagnetism and mechanics: the current generates a force that drives the central rod to move (electricity → force), while the movement of the central rod induces a back electromotive force in the coil (force → electricity), forming a complete electromechanical coupling closed loop.

[0057] The inductance L of a coil is proportional to the square of its number of turns N:

[0058] The first-order electrical time constant of the coil This determines its response speed to current commands:

[0059] The frequency response cutoff frequency (-3dB bandwidth) of the coil is:

[0060] Based on the above analysis, the working mechanism of the main / auxiliary dual-coil frequency division design of this invention is as follows: Main coil (N1=300~500 turns): The inductance is relatively large (typically tens to hundreds of millihenries), and the electrical time constant is... Larger (typically tens of milliseconds), cutoff frequency The frequency is relatively low (typically in the range of a few Hz to tens of Hz), making the main coil suitable for handling low-frequency vibration components. Simultaneously, the high force constant of the main coil... This enables it to generate a large driving force, meeting the need for suppressing low-frequency, large-amplitude vibrations.

[0061] Auxiliary coil (N2=100~200 turns): The inductance is relatively small (typically a few millihenries to tens of millihenries). Smaller (typically a few milliseconds), cutoff frequency The frequency is relatively high (up to tens of Hz to hundreds of Hz), therefore the auxiliary coil is suitable for handling high-frequency vibration components. Although its force constant It is relatively small, but its rapid response capability enables it to effectively track and counteract high-frequency vibrations.

[0062] The complementary frequency responses of the main coil and the auxiliary coil enable the device to achieve wide frequency band coverage from low to high frequencies, resulting in a wide frequency response bandwidth. It can span more than two orders of magnitude. This is the fundamental advantage of the dual-coil frequency division design in this embodiment compared to the traditional single-coil scheme.

[0063] V. Pressure Detection Model of Piezoelectric Sensor A piezoelectric sensor mounted beneath the top load-bearing iron plate utilizes the piezoelectric effect to convert mechanical pressure into a measurable electrical signal. For a piezoelectric sensor element subjected to force along its thickness, the relationship between its output voltage and the applied stress is as follows:

[0064] In the formula: The open-circuit output voltage (V) of the piezoelectric sensor. piezoelectric voltage constant ( ), The stress that the piezoelectric sensor withstands ( ), The thickness of the piezoelectric sensor sheet is in meters (m). The pressure (N) transmitted from the top-loaded iron plate to the piezoelectric sensor. The force-bearing area of ​​the piezoelectric sensor ( ).

[0065] The relationship between the amount of charge generated by the piezoelectric sensor and the applied pressure is as follows:

[0066] In the formula: The amount of charge generated (C). is the piezoelectric charge constant (C / N). The pressure (N) acting on the piezoelectric sensor.

[0067] For the commonly used PZT-5H piezoelectric sensor, , When the top load-bearing plate is subjected to a typical static preload of 1000N, if the piezoelectric sensor thickness... ,area ,but Open circuit output voltage The piezoelectric sensor's response frequency can reach tens of kHz, far exceeding the mechanical vibration frequency, thus enabling real-time tracking of dynamic load changes. The quantization process for dynamic tracking involves the control unit sampling the piezoelectric sensor's output voltage at a frequency of at least 2 kHz (at least 10 times the highest vibration frequency). Perform real-time sampling, according to The dynamic pressure time history is obtained by inverse kinematics at each point; then, the dynamic pressure is decomposed into static load components (mean) and dynamic load components (fluctuation amplitude) by moving average filtering. The static load components are used for load state determination, and the dynamic load components are used for real-time adjustment of vibration reduction control parameters. The pressure tracking lag does not exceed one sampling period. This can meet the real-time tracking requirements of engine vibration load.

[0068] VI. Thermodynamic Analysis of Water Cooling Under active vibration damping conditions, the coil continuously generates Joule heat. If heat is not dissipated in time, the increased temperature will lead to increased coil resistance, decreased magnetic properties of the permanent magnet, and severely reduced operating efficiency. The Joule heat power of the coil is:

[0069] In the formula: Heating power ( ), The effective value of the coil current ( ), Let be the DC resistance of the coil (Ω). The relationship between the resistance of the copper wire and the increase in temperature is as follows:

[0070] In the formula: Reference temperature Resistance at (typically 20℃) The temperature coefficient of resistance of copper is approximately 0.00393 / K. Without effective heat dissipation measures, when the temperature rises from 20℃ to 100℃, the resistance of the copper coil will increase by about 31%, resulting in a decrease in electromagnetic force of about 24% under the same driving voltage, severely affecting vibration damping performance.

[0071] This device employs a water-cooled internal circulation heat dissipation scheme. The coolant flows through water-cooled pipes tightly attached to the heat-conducting iron plates, and the heat is dissipated through convective heat exchange. The convective heat exchange is as follows:

[0072] In the formula: Heat dissipation (W). The convective heat transfer coefficient ( ), The contact area between the water-cooled pipe and the heat-conducting iron sheet ( ), The logarithmic mean temperature difference (K).

[0073] The heat absorbed by the coolant as it flows through the inside of the device is:

[0074] In the formula: coolant mass flow rate ( ), Specific heat capacity of coolant ( ), and These are the coolant outlet and inlet temperatures (K), respectively.

[0075] When the system reaches thermal equilibrium, the heating power of the coil equals the heat dissipation power of the water cooling system, that is... With water ( (This refers to) coolant and flow rate. Taking approximately 3L / min as an example, when the internal heating power of the device is 200W, the temperature difference between the inlet and outlet of the coolant is... The minimal temperature rise indicates that the water-cooled heat dissipation system has sufficient heat capacity margin, which can effectively control the coil operating temperature within a low temperature rise range relative to the environment.

[0076] 3.7 Analysis of Combined Active and Passive Vibration Reduction Performance In the frequency domain, the force transmissibility (transfer function amplitude) of a passive vibration damping system is:

[0077] In the formula: The angular frequency of vibration ( ), The system's natural frequency ( ), For damping ratio. Pure passive vibration reduction only applies to... The high-frequency band has an attenuation effect ( ),exist The transmissivity in the resonance region is actually amplified ( ),exist The low-frequency band has almost no attenuation effect ( ).

[0078] After adding active control, the equivalent dynamic equation becomes:

[0079] A feedback control strategy is adopted to adjust the current of the main coil and the auxiliary coil in real time according to the vibration state. (Low-frequency compensation) (High-frequency compensation) In the formula: and Let be the control transfer functions for low frequency and high frequency, respectively. Then the equivalent stiffness and equivalent damping of the closed-loop system are respectively:

[0080]

[0081] Active control essentially achieves online real-time adjustment of the system's equivalent dynamic parameters—equivalent damping—through the electromagnetic-mechanical coupling effect. The current feedback of the auxiliary coil can be increased over a wide range, thereby suppressing the resonance peak; equivalent stiffness The system's natural frequency can be changed by modulating the acceleration feedback of the main coil to avoid the resonance region.

[0082] Define the total transmissivity of active and passive combined vibration reduction. This is the ratio of the output displacement response to the external force input. Under ideal active control conditions ( With the overall transmissivity approaching zero, the system exhibits zero impedance to the outside world, and the vibration energy is completely absorbed or canceled out by the active force. Under actual engineering conditions, the combination of active and passive systems reduces the vibration transmissivity of the device by 10-30 dB over a wide frequency range (covering the typical vibration frequency range of the engine) compared to a purely passive solution, especially in the low frequency range (<20 Hz) and near the resonant frequency, where the vibration reduction effect is most significant.

[0083] VIII. Summary of Multiphysics Coupling Models Based on the above analysis, the integrated active and passive vibration damping device of this invention involves the fully coupled interaction of three physical fields: electromagnetic field, force field, and temperature field. The complete set of coupling equations is as follows: Circuit equations:

[0084] Force field equations:

[0085] Thermal field equation:

[0086] Piezoelectric equation:

[0087] The multiphysics coupling equations fully reveal the working principle chain of this device: (1) In the circuit equation, the back electromotive force term This demonstrates the coupling path from motion to electrical signal, which makes the electrical behavior of the coil subject to real-time influence from mechanical motion.

[0088] (2) In the force field equation, the electromagnetic force term This embodies the coupling path of electrical signal → motion control, enabling the current to be controllably converted into mechanical force to counteract vibration.

[0089] (3) The thermal field equation describes the thermal management path of electrical energy → thermal energy → heat dissipation. The water cooling system adjusts the thermal field equation to adjust ... and To maintain temperature stability, thereby ensuring the circuit equations The stability of the force field equations is thus guaranteed. Its efficiency is stable.

[0090] (4) The piezoelectric equation converts the top load into an electrical signal. and This provides additional load information input to the control unit, enabling the control strategy to adaptively adjust according to the actual load state. and .

[0091] The fully coupled interaction of the above four physical fields gives the vibration reduction device of the present invention significant advantages in the following aspects: (a) Wide frequency coverage: The large inductance and low cutoff frequency of the main coil complement the small inductance and high cutoff frequency of the auxiliary coil, resulting in a frequency coverage range far exceeding that of a single coil scheme.

[0092] (b) High-efficiency output: The closed yoke ferromagnetic circuit reduces the air gap magnetic induction intensity Maximize the force constant It increases by 40% to 90%, generating greater active damping force under the same current.

[0093] (c) Thermal stability: The water-cooled internal circulation heat dissipation system controls the coil temperature rise within a very small range, thereby maintaining the resistance. Sum of force constants Its stability avoids the degradation of vibration reduction performance caused by high temperature.

[0094] (d) Load sensing: The piezoelectric sensor detects the stress state in real time with a response bandwidth of MHz, providing a load detection bandwidth much higher than the vibration frequency for the control strategy, thus realizing adaptive vibration reduction.

[0095] (e) Electromagnetic-mechanical bidirectional coupling: The back electromotive force provides an inherent electromagnetic damping effect. Even when the active control is not activated, the back electromotive force generated by the moving parts cutting the magnetic lines of force will consume vibration energy, further enhancing the damping energy dissipation capability of the passive section.

[0096] The working principle of the vibration reduction device of this invention is as follows: 1. Passive Operating Condition (Small-Amplitude Daily Vibration): The vibration experienced by the device is detected in real time by the vibration detection unit (vibration sensor). When the vibration sensor detects a vibration displacement amplitude of less than 0.5mm and a main vibration frequency higher than 30Hz, the control unit determines that the device is in a small-amplitude vibration condition. At this time, the vibration energy is transmitted through the central rod to the helical compression spring and the damping pad / rubber isolator. The spring is buffered by elastic deformation, and the damping pad dissipates the energy through viscous damping, achieving passive isolation of small-amplitude vibration. At this time, the main coil and auxiliary coil of the active part are not energized or are in a low-power standby state, but the back electromotive force generated by the movement of the central rod cutting the magnetic lines of force in the air gap magnetic field provides an additional electromagnetic damping effect, enhancing the passive vibration reduction effect. The water cooling system can be suspended to save energy when the internal temperature of the device is lower than the threshold.

[0097] 2. Active operating condition (large-amplitude impact / low-frequency strong vibration): When the vibration sensor detects a vibration displacement amplitude greater than... Or the peak vibration acceleration exceeds And the main vibration frequency is lower than At this time, the control unit determines that the device is under a large impact or low-frequency strong vibration condition. Based on the vibration amplitude detected by the vibration sensor and the pressure signal detected by the piezoelectric sensor, the control unit calculates the required reverse force in the low-frequency range. ,according to The main coil current is calculated, and this controllable current is then applied to the main coil (300~500 turns). With a main coil of 400 turns and an air gap magnetic induction intensity of Effective conductor length per turn For example, force constant When the amplitude of the excitation force to be offset is 500N, the main coil needs to be supplied with a peak current. When the main coil is energized, it generates an electromagnetic driving force with the permanent magnet and the steel core. The drive center rod outputs a controllable force that is opposite in direction or phase to the external vibration. Simultaneously, the water-cooling system starts operating, and the heat dissipation mechanism cools the coil's Joule heat. take away.

[0098] 3. High-frequency auxiliary operating condition: When the vibration detection unit detects a vibration signal with a frequency higher than [the specified frequency], [the condition is as follows]. When the amplitude of a high-frequency component exceeds 20% of the total amplitude, the control unit determines that a high-frequency vibration component exists. At this time, the control unit calculates the required reverse force for the high-frequency band based on the vibration detection signal. ,according to The auxiliary coil current is calculated, and this controllable current is then applied to the auxiliary coil (100~200 turns). With an auxiliary coil of 150 turns, , For example, force constant When the amplitude of the excitation force to be canceled in the high-frequency band is 100N, the auxiliary coil needs to be supplied with a peak current. The auxiliary coil, due to its low inductance, has a high cutoff frequency, enabling it to quickly track high-frequency vibrations and output auxiliary electromagnetic force. It works in conjunction with the main coil to achieve wideband coverage.

[0099] 4. Resonance Suppression Condition: When an external vibration frequency is detected to be close to the device's natural frequency. At that time, the control unit utilizes the equivalent parameter adjustment mechanism of equivalent stiffness and equivalent damping to increase the equivalent damping in real time by adjusting the current feedback gain of the main coil and auxiliary coil. To suppress resonance peaks or adjust equivalent stiffness By shifting the natural frequency, the system is moved away from the resonance state.

[0100] 5. Water-cooled operation: Under active vibration damping conditions, the Joule heat generated by the energized main and auxiliary coils is conducted through the yoke to the heat-conducting iron plate, and then from the heat-conducting iron plate to the water-cooling pipes. An external small water pump drives the coolant to circulate in a closed loop, achieving convective heat transfer according to the coolant's heat absorption equation, carrying heat from inside the device to the outside for dissipation. When the system reaches thermal equilibrium... The coil temperature is stably controlled within the allowable range to ensure resistance. The stability of the electromagnetic driving force is maintained so that it does not decrease due to temperature rise.

[0101] 6. Pressure Detection Function: A piezoelectric sensor installed below the top load-bearing iron plate detects the pressure on the iron plate in real time according to the piezoelectric voltage output equation and the piezoelectric charge output equation. The control unit comprehensively judges the current load and vibration state of the device based on the pressure detection signal and vibration detection signal (acceleration / velocity / displacement), and adjusts the control transfer function accordingly. and This enables adaptive vibration reduction control.

[0102] 7. Optional lower coil auxiliary mode: In application scenarios where the vibration reduction effect needs to be further enhanced, a controllable current can be supplied to the lower coil to generate an auxiliary electromagnetic force between the plunger (moving iron core) and the lower coil, thereby supplementing the active vibration reduction output capability.

[0103] 8. Collaborative Working Mode: The active and passive parts work collaboratively according to the electromagnetic-mechanical coupling dynamic equations: the passive part continuously provides... The foundation vibration isolation energy dissipation, the electromagnetic force of the active part Online adjustments are made based on real-time vibration and pressure detection signals. A water-cooling system ensures thermal balance, while piezoelectric sensors continuously provide load status feedback. All subsystems work together to achieve a wide-band active-passive vibration reduction system.

[0104] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within its scope and spirit, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of the present invention.

Claims

1. An integrated active and passive vibration damping device for aerodynamic boats, characterized in that, It includes an active part and a passive part. The active part is located in the upper half of the device, and the passive part is located in the lower half of the device. The active part and the passive part are integrated in the same housing. The active part is used to reduce vibration in the case of large impact or low frequency strong vibration, and the passive part is used to reduce vibration in the case of small amplitude vibration. The active part includes a piezoelectric sensor for real-time detection of the pressure condition of the device, a vibration detection unit for real-time detection of vibration, a central rod running through the entire device, and a magnetic core, permanent magnet, coil, and yoke distributed from the inside to the outside along the central rod. The permanent magnet, coil, magnetic core, and yoke together constitute an electromagnetic drive circuit, and the central rod moves up and down reciprocally in the vertical direction. The passive component includes an elastic element, a guide rod, a lower coil, an armature, and a damping element. The elastic element is located around the center rod, and the damping element is located at the end of the elastic element away from the active component. The armature is fixed at the end of the center rod away from the active component. The lower coil is symmetrically distributed on both sides of the center rod, with its position corresponding to the position of the armature. The armature and the lower coil form an electromagnetic engagement gap. When the armature and the lower coil are energized, they interact to generate an electromagnetic damping force or driving force acting on the center rod.

2. The active and passive integrated vibration damping device for aerodynamic boats according to claim 1, characterized in that, The coil includes a main coil and an auxiliary coil, which are arranged symmetrically about the axis of the central rod. The number of turns of the main coil is different from the number of turns of the auxiliary coil, so that the main coil and the auxiliary coil are adapted to different frequency bands.

3. The active and passive integrated vibration damping device for aerodynamic boats according to claim 2, characterized in that, The main coil has 300-500 turns, and the auxiliary coil has 100-200 turns.

4. The active and passive integrated vibration damping device for aerodynamic boats according to claim 1, characterized in that, The active part also includes a heat-conducting structure, which is installed on the outside of the yoke and close to the outer periphery of the coil, to conduct away the heat generated by the coil during operation.

5. The active and passive integrated vibration damping device for aerodynamic boats according to claim 4, characterized in that, The heat-conducting structure includes a heat-conducting iron sheet and a water-cooling pipe. The heat-conducting iron sheet is wrapped around the outside of the yoke and closely attached to the outer area of ​​the coil to conduct the heat generated by the coil to the water-cooling pipe. The water-cooling pipe is arranged close to the outer wall of the heat-conducting iron sheet. The pipe is led out from the top of the device through a hole and connected to an external small water pump. The external small water pump drives the coolant in the pipe to circulate between the inside and outside of the device. After the coolant is cooled outside the device, it flows back to the inside of the device, forming a closed internal circulation water-cooling system.

6. The active and passive integrated vibration damping device for aerodynamic boats according to claim 1, characterized in that, A guide sleeve is provided on the outer side of the center rod corresponding to the active part, and a planar flexible elastic element is provided between the end of the center rod away from the passive part and the housing. The planar flexible elastic element is used to radially straighten the center rod and provide axial elastic reset.

7. A method for integrated active and passive vibration reduction in aerodynamic boats, characterized in that, The active and passive integrated vibration damping device for aerodynamic boats according to any one of claims 2-6 specifically includes: The piezoelectric sensor detects the pressure applied to the device in real time and transmits the resulting pressure signal to the control unit. The control unit converts the pressure signal into a real-time pressure value and compares it with a preset pressure threshold. When the real-time pressure value exceeds the preset pressure threshold or the pressure fluctuation amplitude exceeds the preset fluctuation threshold, the control unit determines that the device has entered a loaded working state and controls the main coil and / or auxiliary coil of the active part to be energized. When the real-time pressure value is lower than the preset pressure threshold and continues for more than a preset time, the control unit determines that the device is in a low-load state and controls the main coil and auxiliary coil to be de-energized or enter a low-power standby state. When the equipment being vibration damped is under small-amplitude vibration conditions, the vibration energy is transmitted through the central rod to the elastic and damping elements of the passive part. The elastic deformation of the elastic element buffers the vibration, and the damping element dissipates the vibration energy through viscous damping, thus achieving passive vibration isolation. When the equipment being damped is subjected to large impact or low-frequency strong vibration, a controllable current is supplied to the main coil of the active part, which drives the central rod to output a reverse controllable force through electromagnetic effect, thereby offsetting or weakening the outward transmission of vibration; when the equipment being damped exhibits high-frequency vibration components, a controllable current is supplied to the auxiliary coil to help enhance the high-frequency vibration suppression effect.

8. The active and passive integrated vibration reduction method for aerodynamic boats according to claim 7, characterized in that, The small-amplitude vibration condition, large-amplitude impact or low-frequency strong vibration condition, and high-frequency vibration component are determined by the control unit based on the detection signals from the vibration detection unit and the piezoelectric sensor: when the vibration detection unit detects a vibration displacement amplitude of less than 0.5 mm and a main vibration frequency higher than 30 Hz, it is determined to be a small-amplitude vibration condition; when the vibration displacement amplitude is greater than 2 mm or the peak vibration acceleration exceeds 5 g and the main vibration frequency is lower than 20 Hz, it is determined to be a large-amplitude impact or low-frequency strong vibration condition; when the amplitude of the component with a frequency higher than 50 Hz in the vibration signal accounts for more than 20% of the total amplitude, it is determined that a high-frequency vibration component exists.

9. A method for integrated active and passive vibration reduction for aerodynamic boats according to claim 7, characterized in that, The energizing currents of the main coil and auxiliary coil are calculated and determined in real time by the control unit based on the pressure signal detected by the piezoelectric sensor and the vibration signal detected by the vibration detection unit: main coil current Auxiliary coil current ,in , These are the required reverse forces for the low-frequency and high-frequency bands, calculated by the control unit, respectively. , These are the force constants of the main coil and the auxiliary coil, respectively.

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