High-frequency electromagnetic coupling type damping system and control method thereof
Through the high-frequency electromagnetic coupling shock absorption system, the resonant coupling of the primary and secondary electromagnetic modules is utilized to achieve effective control of the vehicle's full-band vibration and energy recovery, solving the problems of insufficient high-frequency vibration attenuation and unreasonable energy dissipation in the existing technology, and improving the system's self-balancing ability and energy utilization efficiency.
Patent Information
- Application Number
- CN202511100807.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-07
- Publication Date
- 2025-10-10
AI Technical Summary
Existing vehicle shock absorption systems are insufficient in attenuating high-frequency vibrations, and suffer from problems such as unreasonable energy dissipation, high system complexity, high maintenance costs, and insufficient energy recovery capabilities.
A high-frequency electromagnetic coupling shock absorption system is adopted. Through the resonant coupling of the primary and secondary electromagnetic modules, a high-frequency AC power supply is used to drive the primary coil. Combined with a permanent magnet preload component and a guide support mechanism, self-balancing and energy recovery of the suspension are achieved, and energy management is performed using energy recovery or damping circuits.
It achieves effective control of vibrations in the full frequency range of 1Hz-1000Hz, improves driving comfort and handling stability, and has a strong system self-balancing capability and high energy recovery efficiency, which improves system reliability and safety.
Smart Images
Figure CN120756243A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of automobile suspension, and in particular to a high-frequency electromagnetic coupling shock absorption system and a control method thereof. Background Art
[0002] Current vehicle shock absorption systems are broadly categorized into three types: Coil spring-hydraulic cylinder suspension, which relies on mechanical elastic elements to store energy and hydraulic valves to throttle and dissipate it. This structure inadequately attenuates high-frequency road vibrations above 100Hz, and oil seals and pistons are prone to leakage from long-term reciprocating motion, resulting in high maintenance costs. Airbag or hydraulic active suspension uses compressed air or hydraulic cylinders to adjust support height. While offering variable stiffness, this system requires numerous pressure sensors and an ECU for real-time closed-loop control, resulting in a complex system. In the event of a pipeline leak or electronic control failure, support is lost. Linear motor active suspension, which connects a linear motor to the vehicle body and wheels via rigid push rods, can output control force over a wide frequency range. However, this system is heavy and energy-intensive, resulting in a significant increase in unsprung mass. Furthermore, it still relies on a high-bandwidth control system. All three solutions lack energy recovery capabilities, with vibration energy dissipated solely as heat. Summary of the Invention
[0003] In order to overcome the defects of the above-mentioned prior art, the present invention provides the following technical solutions: a high-frequency electromagnetic coupling shock absorption system, comprising: a primary electromagnetic module, the primary electromagnetic module is installed on the vehicle body, and contains a primary coil, a soft magnetic core and a first capacitor connected in series with the primary coil, the primary coil and the first capacitor forming a first LC resonant circuit; a high-frequency AC power supply is electrically connected to the first LC resonant circuit, and is used to drive the primary coil within a frequency range of 1kHz-20kHz; a secondary electromagnetic module, the secondary electromagnetic module is installed on the wheel suspension side, and is coaxially separated from the primary electromagnetic module to form an air gap, the secondary electromagnetic module includes a secondary coil and a second capacitor connected in parallel or in series with the secondary electromagnetic module, or includes a conductive magnetic disk; a permanent magnet A magnetic preload component is arranged in the magnetic circuit of the primary electromagnetic module and / or the secondary electromagnetic module, and is used to provide a constant supporting force of not less than 60% of the vehicle static load when the system is stationary; a guide support mechanism is used to limit the relative movement direction of the secondary electromagnetic module relative to the primary electromagnetic module and set a mechanical limit; an energy recovery or damping circuit is connected to the secondary electromagnetic module, and is used to rectify the secondary induced current and recover electrical energy or dissipate mechanical energy through a resistive load when the vehicle vibrates; wherein the output frequency of the high-frequency AC power supply is set to be 1%-10% higher than the resonant frequency of the first LC resonant circuit, so that the coupling between the primary electromagnetic module and the secondary electromagnetic module has positive stiffness and automatically maintains the balance of the vehicle suspension.
[0004] Preferably, the permanent magnet preload component adopts an annular NdFeB permanent magnet, is axially magnetized, and has a magnetic induction intensity of 0.9-1.3T.
[0005] Preferably, the secondary electromagnetic module adopts a coil-capacitor parallel structure. When the air gap changes, resulting in a change in the coupling coefficient, the equivalent resistance in the secondary electromagnetic module adaptively adjusts the induced current to provide position-dependent electromagnetic damping.
[0006] Preferably, the energy recovery or damping circuit includes: a rectifier bridge, a DC-DC converter and an energy storage device connected in parallel with the vehicle power battery, wherein the DC-DC converter operates in a bidirectional mode, can recover electrical energy during the damping process and supply power to the primary coil inverter when needed.
[0007] Preferably, the guide support mechanism adopts a magnetic bearing structure, in which the static magnetic ring and the dynamic magnetic ring repel each other and bear the lateral load in a non-contact manner.
[0008] Preferably, it also includes a shielding and heat dissipation component, which includes a soft magnetic alloy shielding shell and an integrated microchannel water cooling plate. The microchannel water cooling plate is connected in series with the vehicle cooling circuit to remove the heat generated by the primary coil during high-frequency operation.
[0009] A control method for a high-frequency electromagnetic coupling shock absorption system includes the following steps: S1. By detecting the total mass of the vehicle or the load, the output frequency of the first capacitor or the first power supply is adjusted so that the resonant frequency of the first LC resonant circuit remains constant with changes in the load; S2. The frequency of the high-frequency AC power supply is set to 1.01-1.10 times the resonant frequency to ensure positive stiffness; S3. During vehicle driving, the energy recovery or damping circuit is used to recover the electrical energy induced by the secondary electromagnetic module to the vehicle battery; S4. When the vehicle suspension displacement exceeds a preset safety travel, the suspension travel is limited by the mechanical limit of the guide support mechanism.
[0010] Compared with the existing technology, the present invention has the following advantages: (1) The electromagnetic field is directly driven by a kHz-level high-frequency sinusoidal current, and the magnetic response time can be reduced to milliseconds. By leveraging the resonant coupling amplification effect, the suspension can generate targeted control force for vibrations in the entire frequency range of 1Hz-1000Hz, making a significant contribution to the NVH index in the vehicle. Traditional hydraulic dampers can only effectively suppress bounces below 20Hz and are almost powerless against tire noise and road noise at the hundred-hertz level. However, the present invention can accurately adjust the impedance on the circuit side and absorb specific frequency domains on demand, significantly improving driving comfort and handling stability. (2) The driving frequency of the present invention is maintained in the range of 1-10% above the resonant frequency, which can automatically form positive stiffness, so that the wheel will generate self-resetting force after deviating from the balance position, and can maintain continuous and stable suspension without the need for position sensors and high-bandwidth controllers. (3) The secondary coil or eddy current disk of the present invention induces current when the stroke changes, and feeds it back to the power battery through the rectifier bridge-DC-DC converter. Compared with the traditional damping heat dissipation mode, the system can compensate for its own driving power under continuous bumpy conditions and provide wireless power supply for the wheel-end sensor. The electro-mechanical closed loop with bidirectional energy flow transforms the shock absorber from an energy-consuming component to a micro-energy power generation unit. (4) Even if the inverter loses power or the control circuit fails, the suspension can still maintain support by the permanent magnetic field, and will not cause the vehicle body to collapse like airbag leakage or hydraulic pipe burst. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 It is a schematic flow chart of the working principle of the present invention. DETAILED DESCRIPTION
[0012] The following is combined with Figure 1 The technical solution of the present invention is further explained through specific implementation methods. In the figure: Electric energy flow: from the vehicle power battery through the inverter downward, a high-frequency magnetic field is generated through the primary coil; coupled with the secondary coil / eddy current disk through the magnetic field coupling area; the induced current is fed back to the battery through the rectifier bridge-DC-DC converter to form a closed energy cycle; Mechanical flow: road impact-wheel vertical displacement-coupling coefficient k change; the change of k causes the electromagnetic force F to change, which is transmitted to the vehicle body without contact to achieve suspension and damping; Central magnetic field coupling area: It is the intersection of the two loops at the same time: electromagnetic coupling is converted into mechanical force here; permanent magnetic preload is placed in this area to maintain static support when the power fails.
[0013] The present invention provides a high-frequency electromagnetic coupling type vibration reduction system, comprising:
[0014] The primary electromagnetic module is installed on the vehicle body side and includes: a coil and a tuning capacitor in series to form an LC resonant circuit, and a designed resonant frequency The frequency range is 1kHz-20kHz. The soft magnetic core concentrates the magnetic flux in the axial air gap. The high-frequency AC power supply provides the coil with a sinusoidal current of constant amplitude or adjustable amplitude.
[0015] The secondary electromagnetic module is installed on the wheel suspension side and is coaxially arranged with the primary module. It includes: a conductive coil and a secondary capacitor forming a passive LC resonance or a conductive magnetic disk forming an eddy current circuit; a soft magnetic core enhances coupling.
[0016] The permanent magnet preload component is set in the primary or secondary magnetic circuit to provide a constant support force of 60%–95% for the vehicle's static load. The electromagnetic coil is only responsible for dynamic adjustment.
[0017] The guide support mechanism, including low-friction guide rods, bearings or magnetic bearings, limits the relative movement to the vertical direction and provides mechanical limit in the event of power failure.
[0018] High-frequency drive and resonant tuning circuit (high-frequency inverter, tuning control module) is used to maintain the drive frequency f=(1.01-1.10) , making the coupling exhibit positive stiffness characteristics and achieving self-balancing without sensors.
[0019] Energy recovery / damping loop: When the secondary loop induces current, the energy is recovered to the vehicle battery through the rectifier-DC-DC module; or the road excitation energy is dissipated into heat through an adjustable resistance load to achieve damping adjustment.
[0020] Shielding and heat dissipation components: High magnetic permeability shielding shell and heat pipe-water cooling integrated radiator to ensure EMC compatibility and long-term temperature rise stability.
[0021] A control method for a high-frequency electromagnetic coupling shock absorption system includes the following steps: S1. By detecting the total mass of the vehicle or the load, the output frequency of the first capacitor or the first power supply is adjusted so that the resonant frequency of the first LC resonant circuit remains constant with changes in the load; S2. The frequency of the high-frequency AC power supply is set to 1.01-1.10 times the resonant frequency to ensure positive stiffness; S3. During vehicle driving, the energy recovery or damping circuit is used to recover the electrical energy induced by the secondary electromagnetic module to the vehicle battery; S4. When the vehicle suspension displacement exceeds a preset safety travel, the suspension travel is limited by the mechanical limit of the guide support mechanism.
[0022] The present invention discloses a high-frequency electromagnetic coupling shock absorption system comprising a primary electromagnetic coil assembly located on one side of the vehicle body and a secondary electromagnetic assembly located on the wheel suspension side. The primary coil is excited by a high-frequency AC power supply and forms a resonant circuit with a tuned capacitor. Under high-frequency excitation, the primary coil generates a rapidly varying magnetic field, which is coupled to the secondary side through an air gap. The secondary assembly can be a resonant circuit consisting of a coil and a capacitor (i.e., a secondary coil) or a conductive magnetic material (equivalent to a closed secondary circuit). The alternating magnetic flux induces current or eddy currents in the secondary. Electromagnetic coupling generates an interaction force between the primary and secondary, which can be designed as an attractive or repulsive force to support the vehicle body weight and provide restoring force for the suspension. Utilizing the principle of magnetic field resonant coupling, the primary and secondary circuits resonate at a specific frequency, significantly enhancing coupling efficiency. When the system operates at a frequency close to resonance, significant electromagnetic force can be generated even across a large air gap. By adjusting the drive frequency slightly above the system's electrical resonant frequency, positive stiffness characteristics (i.e., the attractive force increases with increasing gap) can be achieved, thereby achieving stable suspension and balance without active control. This means the suspension system is self-stabilizing: when the wheel moves too close to the vehicle body, the electromagnetic coupling strengthens, triggering a greater reaction force to push it back. When the wheel sinks further away, the coupling weakens, but the current in the resonant circuit increases, increasing the attractive force and pulling it back, causing the system to automatically approach an equilibrium position. This AC magnetic levitation system can generate a restoring force to levitate an object without the use of active controllers or sensors. This is due to the matching of the driving frequency and the resonant characteristics, achieving self-stabilization of the AC suspension. Furthermore, the system absorbs vibration energy through electromagnetic damping. Damping can be achieved by using resistance (or additional resistive elements) in the secondary circuit to dissipate the vibration energy carried by the induced current into heat; or by adjusting the load in the secondary circuit to electromagnetically recover the mechanical vibration energy and feed it back to the power grid or battery. For example, when the wheel moves rapidly up and down due to a bump, the magnetic coupling between the two coils changes, generating eddy currents in the secondary circuit. According to Lenz's law, these eddy currents generate a force opposite to the direction of motion, damping the vibration. This electromagnetic induction-based damping is similar to eddy current braking, offering the advantages of fast response and no contact wear. At the same time, since the primary coil is driven by a high-frequency power supply, it can counteract high-frequency vibrations in real time and filter out micro-vibrations and noise on the road surface.
[0023] The technical effects achieved by the high-frequency electromagnetic coupling shock absorption system of the present invention are as follows: high-frequency response and wide-band vibration reduction: Since the electromagnetic force is directly driven by high-frequency current, the system has an extremely high response speed to vibrations and can generate control force within milliseconds or even faster. This means that high-frequency vibrations and fine road excitations can be more effectively suppressed. Traditional shock absorbers are mainly effective in attenuating low-frequency large vibrations, but are often powerless against subtle vibrations above hundreds of hertz; high-frequency electromagnetic shock absorption systems can operate in the kHz frequency band and actively filter out these high-frequency components, significantly improving ride comfort and in-car quietness. In addition, high-frequency excitation enables the system to act on vibrations in multiple frequency bands simultaneously, and even targeted absorption of specific frequency vibrations can be achieved by adjusting circuit parameters.
[0024] Utilizing the principles of physical resonance and positive stiffness, the suspension achieves self-stabilization at equilibrium. Unlike active suspensions that require complex sensors, this system requires only a simple frequency control loop to maintain the drive frequency, allowing the suspension system to automatically restore equilibrium under disturbances. Furthermore, if the suspension stiffness needs to be changed (for example, switching between soft and hard settings in different driving modes), this can be achieved by adjusting the AC power supply frequency or capacitor value, without replacing any hardware. This passive / quasi-passive (no active control) solution improves system reliability and safety. Even in the event of an electronic control system failure, the suspension still maintains its basic support force provided by the permanent magnets, preventing the sudden collapse of active hydraulic suspensions upon failure.
[0025] Energy recovery and bidirectional coupling: The inherent advantage of electromagnetic shock absorption is that it can convert vibration mechanical energy into electrical energy for reuse or storage. The current induced in the secondary circuit can be connected to the rectifier circuit to store the recovered energy in the vehicle battery, realizing energy recovery. This transforms the shock absorber from a pure energy dissipation element into an energy collector for the vehicle. Through magnetic coupling, when the wheel is pressed down, the electrical energy is fed back, and when the wheel bounces back, it is appropriately output, forming an energy cycle. In addition, because the structure of the primary and secondary resonant circuits is similar to that of a wireless power transmission device, the system can also have wireless power supply / communication functions. For example, suspension coupling can be used to power sensors at the wheel end or transmit data without adding additional hardware.
[0026] Modularity and Adjustability: The damping system can be designed as a modular unit, allowing for easy installation in various suspension configurations. If size constraints are met, the coil size can be increased or the number of coils connected in parallel can be increased to achieve greater load-bearing capacity, adapting to varying weight requirements from passenger cars to trucks. System parameters (inductance, capacitance, drive frequency, etc.) are all electrically adjustable, allowing suspension performance tuning to be primarily accomplished through software and circuit configuration, resulting in rapid response and excellent repeatability. This adjustability enables the use of a single suspension system for a variety of performance characteristics.
Claims
1. A high-frequency electromagnetic coupling shock absorption system, characterized in that: include: a primary electromagnetic module, the primary electromagnetic module being mounted on the vehicle body and comprising a primary coil, a soft magnetic core, and a first capacitor connected in series with the primary coil, the primary coil and the first capacitor forming a first LC resonant circuit; a high-frequency AC power supply, electrically connected to the first LC resonant circuit, and configured to drive the primary coil within a frequency range of 1 kHz to 20 kHz; A secondary electromagnetic module, mounted on the wheel suspension side and coaxially separated from the primary electromagnetic module to form an air gap, the secondary electromagnetic module comprising a secondary coil and a second capacitor connected in parallel or in series therewith, or comprising a conductive magnetic disk; a permanent magnet preload assembly, disposed in the magnetic circuit of the primary electromagnetic module and / or the secondary electromagnetic module, for providing a constant supporting force of not less than 60% of the static load of the vehicle when the system is stationary; A guide support mechanism, used to limit the relative movement direction of the secondary electromagnetic module with respect to the primary electromagnetic module and set a mechanical limit; an energy recovery or damping circuit connected to the secondary electromagnetic module for rectifying the secondary induced current and recovering electrical energy or dissipating mechanical energy through a resistive load when the vehicle vibrates; The output frequency of the high-frequency AC power supply is set to be 1%-10% higher than the resonant frequency of the first LC resonant circuit, so that the coupling between the primary electromagnetic module and the secondary electromagnetic module has positive stiffness and automatically maintains the vehicle suspension balance.
2. The high-frequency electromagnetic coupling vibration reduction system according to claim 1, characterized in that: The permanent magnet preload component adopts an annular NdFeB permanent magnet, is axially magnetized, and has a magnetic induction intensity of 0.9-1.3T.
3. The high-frequency electromagnetic coupling vibration reduction system according to claim 1, characterized in that: The secondary electromagnetic module adopts a coil-capacitor parallel structure. When the air gap changes, resulting in a change in the coupling coefficient, the equivalent resistance in the secondary electromagnetic module adaptively adjusts the induced current to provide position-dependent electromagnetic damping.
4. The high-frequency electromagnetic coupling vibration reduction system according to claim 1, characterized in that: The energy recovery or damping circuit includes: a rectifier bridge, a DC-DC converter and an energy storage device connected in parallel with the vehicle power battery, wherein the DC-DC converter operates in a bidirectional mode, can recover electrical energy during the damping process and supply power to the primary coil inverter when needed.
5. The high-frequency electromagnetic coupling vibration reduction system according to claim 1, characterized in that: The guide support mechanism adopts a magnetic bearing structure, in which a static magnetic ring and a dynamic magnetic ring repel each other and bear the lateral load in a non-contact manner.
6. The high-frequency electromagnetic coupling vibration reduction system according to claim 5, characterized in that: It also includes a shielding and heat dissipation component, which includes a soft magnetic alloy shielding shell and an integrated microchannel water cooling plate. The microchannel water cooling plate is connected in series with the vehicle cooling circuit to remove the heat generated by the primary coil during high-frequency operation.
7. A control method for a high-frequency electromagnetic coupling vibration reduction system according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1. Adjusting the output frequency of the first capacitor or the first power supply by detecting the total mass of the vehicle or the load estimation so that the resonant frequency of the first LC resonant circuit remains constant as the load changes; S2. Setting the frequency of the high-frequency AC power supply to 1.01-1.10 times the resonant frequency to ensure positive stiffness; S3. During vehicle travel, utilizing the energy recovery or damping circuit to recover the electrical energy induced by the secondary electromagnetic module into the vehicle battery; S4. When the vehicle suspension displacement exceeds a preset safety travel, the suspension travel is limited by the mechanical limit of the guide support mechanism.