Self-powered electromagnetic branch circuit damper and control method

Abstract

The invention discloses a self-powered electromagnetic branch circuit damper and a control method.The self-powered electromagnetic branch circuit damper comprises an electromagnetic damping execution unit, a digital adjustable external resistance unit and a control power supply unit, the electromagnetic damping execution unit comprises a top cover and a base, and the top cover and the base are connected through a plurality of supporting threaded rods; a dynamic-static magnetic coupling damping structure is arranged between the top cover and the base, a reset spring is arranged between the dynamic-static magnetic coupling damping structure and the base, and the dynamic-static magnetic coupling damping structure is connected with a digital adjustable external resistance unit and a control power supply unit. The electromagnetic branch damper has an energy collection function at the same time, so that reverse power supply to the control module is realized, coil output of the electromagnetic branch damper is connected to a rectifier bridge circuit and supplies power to a microcontroller, a multi-channel relay module and part of sensor circuits after being temporarily stored by a super capacitor and subjected to voltage stabilization and boosting processing, and a complete self-driven energy path is formed.

Description

Technical Field

[0001] The present invention belongs to the technical field of structural vibration control and energy harvesting, and in particular relates to a self-powered electromagnetic branch circuit damper and a control method thereof. Background Art

[0002] Existing passive dampers have fixed parameters and struggle to accommodate multiple operating conditions. Active control, while offering superior performance, requires a continuous external power supply, resulting in high energy consumption and limited reliability. Semi-active electromagnetic branch circuit dampers (EMSDs) offer a compromise between the two by adjusting external resistors, but they still rely on external power supplies or batteries, making them difficult to operate for extended periods in maintenance-prone environments such as offshore wind turbines and railway bridges. If the induced electrical energy generated by the damper could be promptly recovered and used to drive the control unit, system independence could be significantly improved. However, currently available solutions commonly suffer from the following issues: 1. A lack of self-power supply; 2. Control system failure after power outages; and 3. Inaccurate real-time tracking of the damping force, all of which urgently require improvement. Summary of the Invention

[0003] The purpose of the present invention is to provide a self-powered electromagnetic branch circuit damper and control method to overcome the problems of the existing technology that cannot meet the self-power requirements, the control system failure problem after power failure, and the inaccurate real-time tracking of the damping force.

[0004] To achieve the above object, the technical solution adopted by the present invention is as follows: A self-powered electromagnetic branch circuit damper includes an electromagnetic damping actuator unit, a digitally adjustable external resistance unit and a control power supply unit. The electromagnetic damping actuator unit includes a top cover and a base, which are connected by multiple supporting threaded rods. A dynamic-static magnetic coupling damping structure is arranged between the top cover and the base. A reset spring is arranged between the dynamic-static magnetic coupling damping structure and the base. The dynamic-static magnetic coupling damping structure connects the digitally adjustable external resistance unit and the control power supply unit.

[0005] Preferably, a top partition and a bottom partition are respectively provided at both ends of the dynamic-static magnetic coupling damping structure, and the dynamic-static magnetic coupling damping structure is arranged between the top partition and the bottom partition, and the top partition and the bottom partition are fixedly connected by a connecting fixing rod.

[0006] Preferably, the top partition and the top cover are connected via a plurality of locking bolt rods; the locking bolt rod group includes a locking bolt rod and locking nuts provided at both ends of the locking bolt rod.

[0007] Preferably, the bottom partition and the base are fixedly connected via a plurality of adjusting locking bolt rod groups, wherein the adjusting locking bolt rod groups include a locking screw and a locking nut provided on the locking screw.

[0008] Preferably, the dynamic-static magnetic coupling damping structure includes a multi-turn enameled copper coil winding, a central loading rod is arranged through the middle of the multi-turn enameled copper coil winding, and a permanent magnet group is fixed on the central loading rod.

[0009] Preferably, the permanent magnet group includes a plurality of permanent magnets arranged in an alternating order of NSSNNSSNNS along the axial direction of the central loading rod.

[0010] Preferably, the permanent magnet group and the multi-turn enameled copper coil winding are arranged at intervals.

[0011] Preferably, a spring pad is provided at the upper end of the reset spring, and the spring pad contacts the end face of the permanent magnet group at the bottom of the central loading rod; the lower end of the reset spring is supported on the base.

[0012] Preferably, the digitally adjustable external resistance unit includes multiple channel relay modules, each channel relay module has a fixed-value power resistor connected in series, and the multiple channel relay modules are connected to different pins of the microcontroller; a multi-turn adjustable potentiometer is provided on each channel relay module, and one end of the multi-turn adjustable potentiometer is connected to the total load bus.

[0013] A control method for the self-powered electromagnetic branch circuit damper comprises the following steps: S1, using a laser displacement sensor to obtain the state of the dynamic-static magnetic coupling damping structure, specifically including the displacement and velocity of the dynamic-static magnetic coupling damping structure; the sampling period is 15ms; S2, performing Kalman filtering according to the state of the dynamic-static magnetic coupling damping structure to obtain the optimal estimated state; S3, performing LQR gain calculation based on the final estimated state to obtain the target damping force; S4, use the formula to calculate the target damping value ; S5, the target damping value Rload applies a balanced damping force to the dynamic-static magnetic coupling damping structure.

[0014] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention discloses a self-powered electromagnetic branch circuit damper, comprising an electromagnetic damping execution unit, a digitally adjustable external resistance unit and a control power supply unit. The electromagnetic damping execution unit comprises a top cover and a base, the top cover and the base are connected by a plurality of supporting threaded rods, a dynamic-static magnetic coupling damping structure is arranged between the top cover and the base, a reset spring is arranged between the dynamic-static magnetic coupling damping structure and the base, and the dynamic-static magnetic coupling damping structure connects the digitally adjustable external resistance unit and the control power supply unit. The present invention breaks through the engineering bottleneck of traditional semi-active damping systems that have long relied on external power supply or battery cycle replacement, so that the electromagnetic damper not only participates in vibration control as an energy dissipation device, but also assumes the energy collection function at the same time, thereby realizing reverse power supply to the control module, and connecting the coil output of the electromagnetic branch damper to the rectifier bridge circuit. After temporary storage and voltage stabilization and boosting by a supercapacitor, it supplies power to the microcontroller, multi-channel relay module and some sensor circuits, forming a complete self-driven energy path.

[0015] Optimally, the electromagnetic branch damper generates relative motion under structural excitation, causing the coil to cut through the magnetic lines of force, thereby inducing an AC voltage. This voltage is first converted to DC current through a rectifier bridge circuit and temporarily stored in an 180F supercapacitor, mitigating the impact of voltage fluctuations and vibration interruptions on energy supply stability. Experimental verification has shown that under conventional vehicle road excitation (frequency 5–10Hz), the electromagnetic damper output can continuously provide 1–4W of power, which is higher than the maximum peak power consumption of the control system (<0.8W). While ensuring power supply stability, it can also maintain slow charging of the lithium battery, resulting in autonomous operation under weak vibration and sufficient energy under strong vibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the structure of a self-powered electromagnetic branch circuit damper in an embodiment of the present invention.

[0017] Figure 2 Schematic diagram of the permanent magnet assembly installation structure in an embodiment of the present invention.

[0018] Figure 3 Schematic diagram of the structure of the digitally adjustable external resistance unit in an embodiment of the present invention.

[0019] Figure 4 Schematic diagram of the control power supply unit structure in an embodiment of the present invention.

[0020] Figure 5 Schematic diagram of the control logic of the self-powered electromagnetic branch circuit damper in an embodiment of the present invention.

[0021] Figure 6 1 is a flow chart of a method for controlling a self-powered electromagnetic branch circuit damper in an embodiment of the present invention.

[0022] In the figure, 1. Top cover; 2. Center loading rod; 3. Top partition; 4. Locking bolt rod; 5. Enameled copper coil winding; 6. Connecting fixing rod; 7. Bottom partition; 9. Base; 10. Permanent magnet group; 11. Spring pad; 12. Reinforcement hexagonal nut; 13. Lower fixing hexagonal nut; 14. Multi-turn adjustable potentiometer; 15. Channel relay module. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0024] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0025] The existing technology has the following problems: self-power supply problem: the induced electrical energy of the damper fluctuates violently with the vibration amplitude, making it difficult to directly provide stable power to the controller; power failure safety problem: the damper performance drops sharply after the control link fails, and there is a lack of redundancy; real-time tracking of damping force problem: traditional variable resistors have large step sizes and slow responses, which cannot meet the high-precision requirements of semi-active algorithms for damping force.

[0026] like Figures 1 to 3 As shown, the present invention provides a self-powered electromagnetic branch circuit damper, which specifically includes an electromagnetic damping actuator unit, a digitally adjustable external resistance unit and a control power supply unit. The electromagnetic damping actuator unit includes a top cover 1 and a base 9, and the top cover 1 and the base 9 are connected by multiple supporting threaded rods 4. A dynamic-static magnetic coupling damping structure is provided between the top cover 1 and the base 9, and a reset spring 8 is provided between the dynamic-static magnetic coupling damping structure and the base 9.

[0027] In the specific embodiments of this application, Figure 1As shown, in order to ensure that the magnetic circuit is aligned with the machine, a top partition 3 and a bottom partition 7 are respectively provided at both ends of the dynamic-static magnetic coupling damping structure. The dynamic-static magnetic coupling damping structure is arranged between the top partition 3 and the bottom partition 7, and the top partition 3 and the bottom partition 7 are fixedly connected by a connecting fixing rod 6.

[0028] In a specific embodiment of the present application, the top partition 3 and the top cover 1 are connected by a plurality of locking bolt rods 4. The locking bolt rod group 4 includes locking bolt rods and locking nuts disposed at both ends of the locking bolt rods, and the locking nuts are used to adjust the distance between the top partition 3 and the top cover 1. The bottom partition 7 and the base 9 are fixedly connected by a plurality of adjustable locking bolt rod groups 13. The adjustable locking bolt rod group 13 includes locking screws and locking nuts disposed on the locking screws. In a specific embodiment of the present application, the locking screws in the adjustable locking bolt rod group 13 and the connecting and fixing rods are the same connecting rod. In this way, the axial preload between the top partition 3, the top cover 1, the bottom partition 7 and the base 9 is achieved through a three-stage locking system. The locking bolt rods located between the top partition 3 and the top cover 1 at the upper end are locked by hexagonal nuts 4. The top partition 3 and the bottom partition 7 in the coil are fixed by reinforcing hexagonal nuts 12. The bottom partition 7 and the base 9 at the lower end are fixed by lower fixing hexagonal nuts 13. The three sets of bolts and nuts jointly apply axial tension, so that the entire frame can maintain coaxiality and tightening force in a long-term vibration environment, avoiding coil bore sweeping or uneven magnetic gap.

[0029] In the specific embodiment of the present application, the top cover 1 is made of an acrylic disc, and the central opening of the top cover 1 allows the central loading rod 2 to pass through and be rigidly connected to the controlled structure. The dynamic-static magnetic coupling damping structure includes a multi-turn enameled copper coil winding 5, and the central loading rod 2 is arranged in the middle of the multi-turn enameled copper coil winding 5. A permanent magnet group 10 is fixed to the central loading rod 2, such as Figure 2 As shown, the permanent magnet group 10 includes a plurality of permanent magnets arranged in an alternating order of NSSNNSSNNS along the axial direction of the central loading rod.

[0030] The permanent magnet group 10 is spaced apart from the multi-turn enameled copper coil winding 5, and the spacing between the multi-turn enameled copper coil winding 5 and the permanent magnet group 10 is 2-4 mm. When external vibration drives the central loading rod 2 to move up and down, the permanent magnet cuts the coil magnetic flux in the magnetic gap, inducing an electromotive force at both ends of the coil. After the circuit is connected to the adjustable external resistance, an energy-consuming current is formed, and the electromagnetic coupling force reacts on the loading rod, thereby generating damping.

[0031] In a specific embodiment of the present application, the reset function of the electromagnetic damping actuator is realized by the reset spring 8 between the dynamic-static magnetic coupling damping structure and the base 9; specifically, a spring pad 11 is provided at the upper end of the reset spring 8, and the spring pad 11 contacts the end face of the permanent magnet group 10 at the bottom of the center loading rod 2; the lower end of the reset spring 8 is supported on the base 9, and the upper end transmits force to the loading rod through the spring pad 11, which can push the permanent magnet group back to the center position after the external excitation stops, ensuring the symmetrical initial state of the device and avoiding magnet drift. In the present application, the dynamic-static magnetic coupling damping structure, the top cover 1 and the base 9 are pre-tightened by screws to form an integrated module, which can be directly embedded in the vehicle suspension, bridge isolation or equipment vibration reduction system, and cooperated with the digitally adjustable external resistance to realize the integrated damping-energy recovery semi-active vibration control.

[0032] In such Figure 3 、 Figure 4 The digitally adjustable external resistance unit shown specifically includes multiple channel relay modules, each of which has a fixed-value power resistor connected in series. The multiple channel relay modules are connected to different pins of the microcontroller; each channel relay module is connected to a multi-turn adjustable potentiometer 14, and one end of the multi-turn adjustable potentiometer 14 is connected in parallel to the total load bus, which is used to flexibly fine-tune the equivalent impedance during the experimental debugging phase or provide a manual temporary code when the MCU loses power to ensure that the damper can still maintain a controllable resistance value during shutdown maintenance.

[0033] In a specific embodiment of the present application, the digitally adjustable external resistance unit comprises eight channel relay modules, each of which is connected in series with a fixed-value power resistor. These resistors are weighted according to binary weights, namely 1Ω, 2Ω, 4Ω, 8Ω, 16Ω, 32Ω, 64Ω, and 128Ω, forming an adjustable resistance array ranging from 1 to 255Ω with a resolution of 1Ω. The control pins of all channel relay modules are connected to the IO ports of a microcontroller (in this case, an ATmega328P). Digital signals (high level to engage, low level to release) control the on and off states of the relays, enabling rapid adjustment of the damping force. This resistor array is actually connected to the output circuit of the electromagnetic coil, forming an adjustable electrical load whose damping force is determined by the electromechanical coupling coefficient and the internal resistance of the coil. Furthermore, when all channel relay modules are disconnected, the system defaults to high-impedance mode (255Ω) to ensure a minimum damping baseline in the event of a power outage. In addition, each channel relay module is connected in parallel with a multi-turn adjustable potentiometer, which is connected to the total load bus, so as to facilitate impedance fine-tuning during the experimental stage or manual setting of the resistance value when the microcontroller is powered off.

[0034] The control and power supply unit (CPSU) ensures stable power supply and closed-loop operation even without an external power source. It consists of a series-connected rectifier bridge circuit, a supercapacitor energy storage unit, and a boost and voltage regulator module. The rectifier bridge circuit converts the AC voltage induced in the electromagnetic coil into DC voltage, using high-voltage and reliable rectifier components such as the 1N4007 diode. The supercapacitor energy storage unit uses a 180F ultra-high-capacity capacitor to temporarily store and smooth transient energy, preventing voltage fluctuations from impacting downstream equipment. The boost and voltage regulator module, featuring an LM2577 boost control chip, is coupled with a 100μH inductor, a 1N5822 Schottky diode, and a π-type filter network to form a highly efficient DC-DC converter circuit. This circuit boosts the bus voltage to approximately 8V to charge a 7.2V / 800mAh lithium battery. The battery then outputs a stable 5V supply through the voltage regulator module, providing power for the microcontroller, relay board, and sensors.

[0035] The digitally adjustable external resistance unit and the control power supply unit are connected in parallel. Since the power supply circuit is externally connected to a supercapacitor, it is approximately regarded as an open circuit. Therefore, the resistance value of the external resistor is completely determined by the digitally adjustable external resistance unit.

[0036] In such Figure 3 and Figure 4 The digitally adjustable external resistance unit shown is composed of 8 relay control channels arranged in parallel. Each channel contains a multi-turn adjustable potentiometer, and its connection to the main current circuit of the electromagnetic damper is controlled by a set of single-pole single-throw relays. Each potentiometer can independently adjust the resistance value, thus forming multiple resistance units with preset accuracy and combinability.

[0037] The output of each multi-turn adjustable potentiometer is connected in parallel to the total load bus, and its conduction is controlled by a relay. The microcontroller (such as ATmega328P) sends high and low level signals through its IO ports (such as PD2–PD7, PB0–PB1) to control the on and off of the corresponding relays, thereby dynamically changing the number of potentiometers connected to the main circuit. This structure allows the system to adjust the potentiometers of multiple resistance channels through relay combinations, thereby forming an equivalent total impedance that can be discretely adjusted. Since the resistance value of each potentiometer has been preset to a specific value during system debugging, the control end does not need to set the resistance size bit by bit. It only needs to use the formula to calculate the target damping value based on the target damping force. , the output impedance can be made close to the target damping requirement.

[0038] and Figure 4Combined with the schematic diagram in , it can be seen that the entire adjustable resistor array is connected to the rectifier output end of the electromagnetic damper coil through two terminals, forming a current loop; when the damper is powered off, the relay defaults to the closed state, and the system can retain a certain resistance path through the pre-adjusted potentiometer combination, thereby ensuring basic damping function and structural safety.

[0039] In a specific embodiment of the present application, eight channel relay modules 15 are arranged in a row, with fixed-value power resistors connected in series within each channel. The resistance values ​​are, according to binary weighting, 1 Ω, 2 Ω, 4 Ω, 8 Ω, 16 Ω, 32 Ω, 64 Ω, and 128 Ω. The microcontroller MCU specifically employs an ATmega328P microcontroller. The ATmega328P microcontroller drives the relay coils of the eight channel relay modules 15S1–S8 via I / O pins PB0, PB1, and PD2–PD7. By outputting corresponding combinations of high levels, the ATmega328P microcontroller can switch various resistance values ​​in and out of the circuit within milliseconds, achieving a continuously adjustable external load with a full range of 1–255Ω in 1Ω steps. When all relays are disconnected, the circuit is open, achieving "zero resistance" or failure protection.

[0040] In the self-powered electromagnetic branch circuit damper described in this application, the digitally adjustable external resistance module utilizes a resistor array consisting of eight relay modules. Each channel is connected in series with a fixed-value power resistor. These resistors are weighted in binary order: 1Ω, 2Ω, 4Ω, 8Ω, 16Ω, 32Ω, 64Ω, and 128Ω. This design allows the system to precisely adjust the equivalent resistance within a range of 1–255Ω with a resolution of 1Ω by switching the relays on and off, making it suitable for mapping target damping force to corresponding electrical loads. An ATmega328P microcontroller serves as the control core, driving the control coils of each relay channel via its eight digital I / O pins (PB0, PB1, PD2–PD7). During normal operation, the control program processes real-time structural states (such as velocity and displacement) using a Kalman filter and LQR control algorithm to output a target damping force value. The system then calculates the resistance value that best approximates this target damping force using a formula. Next, the resistance value is converted into an 8-bit binary code. The corresponding high-level signal drives a set of relays to close, connecting the specific resistor combination to the circuit. Because the relays respond within milliseconds, the entire resistance switching process can be adjusted online at high speed, ensuring the semi-active control algorithm's response requirements for "real-time tracking of damping force."

[0041] Furthermore, when all relays are disconnected, the equivalent resistance still remains, disconnecting the entire load circuit and making it impossible for the system to control the relays. This state is defined by the system as "open circuit protection" mode. This occurs when the system experiences a power outage, control failure, or low battery voltage failure. All relays naturally disconnect due to the loss of power to the coils, entering a safe passive reactive mode. At this point, all potentiometers in the circuit are connected in series, still providing passive damping force to the electromagnetic branch circuit damper. Therefore, this relay-resistor array not only possesses excellent dynamic control accuracy but also clear fault protection logic, making it a key module for achieving the dual goals of "controllable impedance + safe degradation."

[0042] like Figure 4 As shown, the control and power supply unit consists of a series-connected rectifier bridge circuit, a capacitor bank, and a boost control circuit. Together, they convert the alternating induction voltage across the electromagnetic branch damper coil into a stable DC voltage that can operate the microcontroller (MCU) and relays, enabling self-powered operation of the system. First, the rectifier bridge circuit uses four diodes to form a bridge rectifier structure, rectifying the AC voltage output by the electromagnetic damper into a unidirectional DC current. The positive and negative output terminals of the rectifier are labeled IN+ and IN-, respectively, and serve as the input power for the subsequent capacitor bank and boost circuit. The first component connected after the rectifier output is a large-capacity supercapacitor, which provides charge storage and low-frequency filtering. This provides buffered energy output during discontinuous vibration or startup phases, ensuring power supply stability. To suppress voltage ripple and inrush current, an RC network consisting of a 2.2kΩ resistor and a 330nF capacitor is connected in parallel after the supercapacitor for current limiting and filtering. A 1N5822 Schottky diode is also connected in series to prevent voltage backflow into the rectifier bridge and protect upstream components. After the capacitor bank, the circuit enters the boost control stage, centered around the LM2577 DC-DC boost chip. This chip steadily boosts the low-voltage DC input (e.g., 2–5V) to the required output voltage (e.g., 7.2V or 8V) required by the downstream stage. This provides charging power for the system's lithium-ion battery pack and operating voltage for the microcontroller, digital relay module, and other components. The LM2577, along with a peripheral 100μH inductor and Schottky diode, forms a boost topology. A large electrolytic capacitor (10,000μF, 63V) is connected in parallel at the output to further smooth the boosted output voltage, filter out high-frequency ripple, and ensure stable and reliable power supply to subsequent circuits. Finally, the boosted, regulated DC voltage is delivered to the lithium-ion battery pack and ATmega328P microcontroller via the OUT+ and OUT- terminals, enabling self-powered operation of the entire digital control system.

[0043] The bidirectional induced current from the damper coil in the electromagnetic branch circuit is rectified by the bridge rectifier circuit in the figure to form a DC bus. The capacitor bank's ultra-large 180F supercapacitor then buffers transient energy, suppressing surges during excitation startup. Finally, the boost control circuit, comprised of an LM2577 boost controller chip, a 100µH inductor, a 1N5822 Schottky diode, and a π-type capacitor-resistor network, forms a high-efficiency DC-DC converter, boosting the bus voltage to a stable 8V, typically required for battery charging. The boosted output is further smoothed by a 10,000µF filter electrolytic capacitor before being fed into the lithium battery pack, providing a regulated 5V supply to the MCU, relay board, and peripheral sensors. If the battery voltage is low or an abnormal power outage occurs, the firmware reduces relay activation frequency or releases all relays, automatically reverting the system to fixed-resistance operation. As a result, digital external resistance adjustment, energy harvesting and microcontroller logic form a closed loop: the MCU combines relays in real time based on the target damping force calculated by the Kalman-LQR algorithm, achieving coordination among the three domains of "vibration-electric energy-damping".

[0044] In a specific embodiment of the present invention, the control and energy flow process of the self-powered electromagnetic branch circuit damper of the present invention is as follows: Figure 5 As shown in Figure 2, the core of the self-powered electromagnetic branch-circuit damper is the electromagnetic branch-circuit damper, which generates an electromagnetic response based on an excitation signal to regulate structural vibration. The self-powered electromagnetic branch-circuit damper is connected to a relay module to switch the damping channels. The relay is directly controlled by logic signals output by a microcontroller. The microcontroller obtains structural dynamic information such as displacement, velocity, or acceleration collected by sensors and makes control decisions based on embedded control algorithms such as LQR or balanced logic control.

[0045] The control algorithm calculates the target damping state based on the sensor data, thereby driving the microcontroller to issue control instructions and ultimately controlling the conduction state of the relay.

[0046] In terms of the energy path, the entire system is powered by a battery. The electrical energy flows through a relay and enters the electromagnetic branch circuit damper to achieve the excitation process. During this energy conversion process, since electromagnetic damping is essentially an energy dissipation mechanism, some of the input energy is lost as heat. The control module, including the sensor and microcontroller, also relies on battery power. Together, these modules form the system's closed-loop control path.

[0047] This invention overcomes the engineering bottleneck of traditional semi-active damping systems, which rely on external power supplies or periodic battery replacement. Through the coordinated design of the structure and circuits, the system enables the electromagnetic damper to not only participate in vibration control as an energy dissipator but also simultaneously perform energy harvesting, thereby achieving reverse power supply to the control module and establishing a self-closed loop path of energy harvesting, damping control, and energy feedback. The coil output of the electromagnetic branch damper is connected to a rectifier bridge circuit. After temporary storage and voltage stabilization and boosting by a supercapacitor, it powers a microcontroller (ATmega328P), a multi-channel relay module, and some sensor circuits, forming a complete self-driven energy path.

[0048] Regarding energy conversion and efficiency, the electromagnetic branch damper generates relative motion under structural excitation, causing the coil to cut through magnetic flux lines, inducing an AC voltage. This voltage is first converted to DC by a rectifier bridge circuit and temporarily stored in an 180F supercapacitor, mitigating the impact of voltage fluctuations and vibration interruptions on power supply stability. A DC-DC boost chip (such as the LM2577) then boosts the capacitor output voltage to the controller's operating voltage range (e.g., 5–8V). A filter capacitor then provides a low-ripple DC output. Ultimately, this energy is directly used to drive low-power control components such as the MCU, relay coil, and ADC acquisition module. Experimental verification shows that under typical vehicle road excitation (frequency 5–10Hz), the electromagnetic damper can continuously provide 1–4W of power, exceeding the control system's maximum peak power consumption (<0.8W). This ensures power supply stability while also allowing the lithium battery to slowly charge, resulting in autonomous operation under weak vibrations and energy surplus under strong vibrations.

[0049] Furthermore, to improve energy efficiency, the system incorporates a "damping force-resistance value" calculation mechanism at the control logic level. The target damping force is calculated through LQR control, and the controller outputs the corresponding relay combination, enabling precise switching of digitally adjustable resistors. This approach, rather than relying on continuously variable loads (such as MOSFET analog resistors), utilizes a discrete resistor array, significantly reducing control energy consumption and improving the system's anti-interference capabilities. Especially when vehicle vibration is minimal, the control algorithm proactively enters a "low damping, low energy consumption" mode, further reducing power consumption and balancing energy supply and demand.

[0050] In a specific embodiment of the present invention, a vibration control flow chart of a self-powered electromagnetic branch circuit damper is shown as follows: Figure 6 As shown, the following steps are included: S1, through the laser displacement sensor arranged near the dynamic-static magnetic coupling damping structure, achieves high-precision non-contact measurement of the relative displacement between the coil and the permanent magnet.

[0051] To capture the complete system dynamic state, the control system uses a numerical difference method to time-differentiate the acquired displacement and calculate the velocity component. Displacement and velocity together constitute the system's state vector, a prerequisite for precise feedback regulation. The sampling period is set to 15 milliseconds, meeting the real-time requirements of the LQR controller while balancing energy consumption and data processing complexity. The acquired state variables are then fed into the Kalman filter module in the next stage.

[0052] In step S2, the state information collected in step S1 is fused and filtered using a Kalman filter to eliminate instabilities caused by sensor measurement errors, environmental interference, and computational discrete errors. The Kalman filter dynamically estimates the state using the minimum mean square error criterion by combining the system state prediction model with actual measurement data, thereby outputting a more stable, continuous, and reliable optimal estimated state. The filtered state is directly used as the input to the next LQR controller. In S3, after obtaining the optimal system state estimate, the system enters the LQR (Linear Quadratic Regulator) controller stage. Based on the pre-set state feedback weight matrix and control energy consumption weight matrix, the optimal feedback gain matrix is ​​obtained by solving the Lyapunov equation. The optimal target damping force Fd for the current operating condition is calculated using the formula Fd = -Kx.

[0053] The LQR controller balances system response performance with control input energy consumption, minimizing power output while ensuring structural vibration reduction. The calculated damping force is used to determine the required load resistance, which serves as the control target for the electromagnetic damping circuit. S4, the target damping force output by the previous step LQR controller As the search index, combined with the real-time speed of the input, the formula is:

[0054] Get the corresponding optimal load resistance The output is a resistance value between 1–255Ω with a resolution of 1Ω, corresponding to the resistor array configuration controlled by eight relays. S5, the microcontroller (ATmega328P) calculates the optimal load resistance. , controlling the on / off states of eight relay modules, thereby dynamically configuring the digital resistor array. Each relay controls a binary-weighted, multi-turn adjustable resistor (1Ω to 128Ω). By switching on different relays, any integer resistance value between 1–255Ω can be connected. The relay response time is less than 100ms, ensuring timely and stable resistance switching. This module serves as the "execution interface" that converts control targets into physical regulation signals, connecting the control layer and the hardware circuit layer.

[0055] In the specific embodiment of this application, calculation + linear interpolation is used to map the expected damping force to the nearest resistance combination; the GPIO port sends bit enable to the 8-way MOSFET relay, high level pulls in, low level releases, and the switching sequence follows the "break before make" principle to avoid instantaneous short circuit. If the resistance value changes by less than 1 Ω in two consecutive cycles, the current state is maintained to reduce relay jitter. Actual damping force It is derived from the following formula:

[0056] in is the electromechanical coupling coefficient between the electromagnetic branch circuit damper coil and the permanent magnet, and are the actual load resistance and the coil internal resistance, is the relative speed.

[0057] In a specific embodiment of the present invention, the induced current at both ends of the coil is rectified by a full-bridge and transiently stored in a supercapacitor before being boosted to 8V by an LM2577 to charge a 7.2V / 800mAh lithium battery. The MCU, relay, and sensor are all powered by a 7.2V / 800mAh lithium battery, thus eliminating dependence on an external power supply.

[0058] An 8-way MOSFET relay 15 is connected to the MCU ATmega328PI / O port, and a binary weighted power resistor 1-128 Ω is connected in series. The MCU runs the LQG control algorithm of Kalman filtering + LQR, and calculates in real time the target damping force mapped to a combined resistance with a step size of 1 Ω. The relay switching delay is less than 100 ms, achieving 255-level fine damping adjustment.

[0059] The normally closed contacts are designed so that all relays are automatically released to a fixed 255 channel when the MCU or battery voltage is lower than 5V; passive damping is still retained in the extreme case of no control power supply to ensure structural safety.

[0060] This invention achieves an average output of 280mW at 5Hz and 4V resonant conditions, fully charging an 800mAh battery in 2 hours and enabling 24-hour continuous closed-loop control without the need for an external power supply. After a power outage, damping drops by only 6%, stabilizing in passive mode and avoiding "control cliffs" while meeting safety redundancy requirements. Damping accuracy and response are significantly improved: 1Ω resolution and 1ms switching result in a damping force tracking error of ≤±5%. Measured peak displacement is 64.7% lower than open-loop control and 42.9% lower than Sky-hook control.

Claims

1. A self-powered electromagnetic branch circuit damper, characterized in that: The invention comprises an electromagnetic damping execution unit, a digitally adjustable external resistance unit and a control power supply unit, wherein the electromagnetic damping execution unit comprises a top cover (1) and a base (9), wherein the top cover (1) and the base (9) are connected via a plurality of supporting threaded rods (4), a dynamic-static magnetic coupling damping structure is provided between the top cover (1) and the base (9), a reset spring (8) is provided between the dynamic-static magnetic coupling damping structure and the base (9), and the dynamic-static magnetic coupling damping structure is connected to the digitally adjustable external resistance unit and the control power supply unit.

2. A self-powered electromagnetic branch circuit damper according to claim 1, characterized in that: A top partition plate (3) and a bottom partition plate (7) are respectively provided at both ends of the dynamic-static magnetic coupling damping structure. The dynamic-static magnetic coupling damping structure is provided between the top partition plate (3) and the bottom partition plate (7). The top partition plate (3) and the bottom partition plate (7) are fixedly connected via a connecting fixing rod.

3. A self-powered electromagnetic branch circuit damper according to claim 2, characterized in that: The top partition (3) and the top cover (1) are connected via a plurality of locking bolt rods (4); the locking bolt rod group (4) comprises a locking bolt rod and locking nuts arranged at both ends of the locking bolt rod.

4. A self-powered electromagnetic branch circuit damper according to claim 2, characterized in that: The bottom partition (7) and the base (9) are fixedly connected via a plurality of adjusting locking bolt rod groups (13), wherein the adjusting locking bolt rod group (13) comprises a locking screw and a locking nut arranged on the locking screw.

5. A self-powered electromagnetic branch circuit damper according to claim 1, characterized in that: The dynamic-static magnetic coupling damping structure comprises a multi-turn enameled copper coil winding (5), a central loading rod (2) passing through the middle of the multi-turn enameled copper coil winding (5), and a permanent magnet group (10) is fixed on the central loading rod (2).

6. A self-powered electromagnetic branch circuit damper according to claim 5, characterized in that: The permanent magnet group (10) comprises a plurality of permanent magnets arranged in an alternating order of NSSNNSSNNS along the axial direction of the central loading rod, and the permanent magnet group (10) is spaced apart from the multi-turn enameled copper coil winding (5).

7. A self-powered electromagnetic branch circuit damper according to claim 1, characterized in that: A spring pad (11) is provided at the upper end of the reset spring (8), and the spring pad (11) contacts the end surface of the permanent magnet group (10) at the bottom of the central loading rod (2); the lower end of the reset spring (8) is supported on the base (9).

8. A self-powered electromagnetic branch circuit damper according to claim 1, characterized in that: The digital adjustable external resistance unit includes a plurality of channel relay modules, each channel relay module has a fixed-value power resistor connected in series, and the plurality of channel relay modules are connected to different pins of a microcontroller; a multi-turn adjustable potentiometer (14) is provided on each channel relay module, and one end of the multi-turn adjustable potentiometer (14) is connected in parallel to a total load bus.

9. A self-powered electromagnetic branch circuit damper according to claim 8, characterized in that: The control power supply unit includes a rectifier bridge circuit, a supercapacitor energy storage unit and a boost and voltage stabilization module connected in series: the rectifier bridge circuit is used to rectify the AC voltage induced in the electromagnetic coil into a DC voltage; the supercapacitor energy storage unit is used to temporarily store and smooth transient energy; the boost and voltage stabilization module is used to stably increase the bus voltage to charge the lithium battery. At the same time, the battery outputs a stable 5V power supply through the voltage stabilization module to provide working power for the microcontroller, relay board and sensor.

10. A control method for the self-powered electromagnetic branch circuit damper according to claim 1, characterized in that: The following steps are involved: S1, using a laser displacement sensor to obtain the state of the dynamic-static magnetic coupling damping structure, specifically including the displacement and velocity of the dynamic-static magnetic coupling damping structure; the sampling period is 15ms; S2, performing Kalman filtering according to the state of the dynamic-static magnetic coupling damping structure to obtain the optimal estimated state; S3, performing LQR gain calculation based on the final estimated state to obtain the target damping force; S4, use the formula to calculate the target damping value ; S5, the target damping value Rload applies a balanced damping force to the dynamic-static magnetic coupling damping structure.

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