Variable impedance adapted vibration feature circumferential stack piezoelectric shunt vibration damping device and method

Abstract

The application provides a variable impedance adaptive vibration characteristic circumferential stack piezoelectric shunt damping device and method, the device comprises: a circumferential stack piezoelectric damping ring, a piezoelectric stack block, a wedge spring and a variable impedance shunt circuit module, the piezoelectric stack block and the wedge spring are arranged on the mounting bracket of the circumferential stack piezoelectric damping ring, the shaft section to be damped is arranged on the inner side of the circumferential stack piezoelectric damping ring through a bearing, multiple piezoelectric stack blocks are connected in parallel, and the variable impedance shunt circuit module is connected with the total output of the piezoelectric stack block.The technical scheme of the application overcomes the problem that the piezoelectric shunt damping device in the prior art is mostly designed for a single frequency or a fixed working condition, the circuit parameter adjustment dimension is single, the adaptive matching capability for complex and variable vibration characteristics is poor, and the damping effect is poor in the variable working condition and multiple excitation source scene.

Description

Technical Field

[0001] This invention relates to the field of vibration control of rotor systems, and specifically to a circumferentially stacked piezoelectric shunt vibration reduction device and method with variable impedance adapted to vibration characteristics. Background Technology

[0002] With the continuous development of aviation, shipbuilding, automobile and other fields, people's requirements for vibration reduction and noise reduction of transmission systems are increasing. Existing technologies mainly include passive vibration reduction and active vibration reduction. Passive vibration reduction devices (such as squeeze film dampers and particle dampers) are widely used but have poor adaptability and can only achieve effective vibration reduction under specific speed and load conditions. Active vibration reduction devices (such as electromagnetic active dampers) have complex structures and control algorithms, slow response and limited vibration suppression range.

[0003] Piezoelectric shunt damping technology, as a semi-active vibration reduction technique, converts mechanical vibration energy into electrical energy and dissipates it by connecting an adjustable shunt circuit to a piezoelectric element. It offers advantages such as adjustable damping parameters, fast response speed, and compact structure. However, most existing piezoelectric shunt damping devices are designed for single frequencies or fixed operating conditions. Their circuit parameter adjustment dimensions are limited, lacking the ability to adaptively match complex and variable vibration characteristics, resulting in poor vibration reduction performance under varying operating conditions and multiple excitation sources.

[0004] Therefore, there is a need for a circumferentially stacked piezoelectric shunt vibration reduction device and method that can adaptively match the complex and variable vibration characteristics. Summary of the Invention

[0005] The main objective of this invention is to provide a circumferentially stacked piezoelectric shunt vibration reduction device and method with variable impedance to adapt to vibration characteristics, in order to solve the problem that most existing piezoelectric shunt vibration reduction devices are designed for single frequency or fixed working conditions, with a single dimension of circuit parameter adjustment and a lack of adaptive matching capability for complex and variable vibration characteristics, resulting in poor vibration reduction effect in variable working conditions and multi-excitation source scenarios.

[0006] To achieve the above objectives, the present invention provides a circumferential stacked piezoelectric shunt vibration damping device with variable impedance adapted to vibration characteristics, comprising: a circumferential stacked piezoelectric damping ring, piezoelectric stack blocks, wedge springs, and a variable impedance shunt circuit module. The piezoelectric stack blocks and wedge springs are alternately arranged on the mounting bracket of the circumferential stacked piezoelectric damping ring. The shaft segment to be damped is sleeved on the inner side of the circumferential stacked piezoelectric damping ring through bearings. Multiple piezoelectric stack blocks are connected in parallel, and the variable impedance shunt circuit module is connected to the total output of the piezoelectric stack blocks.

[0007] Furthermore, the circumferentially stacked piezoelectric vibration damping ring includes an inner ring, an outer ring, and a mounting bracket. The mounting bracket is provided between the inner ring and the outer ring. The mounting bracket has a double-layered mounting groove. The piezoelectric stacked blocks and wedge springs are arranged alternately in the mounting groove. Inner ring grooves are uniformly provided on the outer side wall of the inner ring, and outer ring grooves are uniformly provided on the inner side wall of the outer ring. The end face of the small end of the wedge spring is engaged in the inner ring groove, and the end face of the large end of the wedge spring is engaged in the outer ring groove. A preload is applied to the wedge spring through the preload screw on the outer ring, so that the wedge spring is in a semi-compressed state.

[0008] Furthermore, the two working surfaces of the piezoelectric stack block along the compression direction abut against the two adjacent wedge springs, respectively.

[0009] Furthermore, the piezoelectric stack is composed of multiple piezoelectric ceramic sheets stacked in series, and the non-working surfaces of the piezoelectric stack are bonded to the mounting bracket with epoxy adhesive.

[0010] Furthermore, multiple arc-shaped grooves are evenly opened on the large end of the wedge spring. The contact surface between the wedge spring and the piezoelectric stack is a wedge-shaped working surface. The opening of the arc-shaped groove is located on the wedge-shaped working surface of the wedge spring. The arc-shaped groove causes the wedge spring to generate radial tension and compression, which squeezes the piezoelectric stack on both sides of the wedge spring.

[0011] Furthermore, a floating gap is left between the mounting bracket and the inner ring, which provides displacement space for the vibration of the shaft section to be damped and the compression of the wedge spring.

[0012] Furthermore, it also includes: a vibration sensing module, which is located on the system housing and is used to detect vibration signals on the system housing. The system housing is fitted outside the outer ring of the circumferentially stacked piezoelectric damping ring, and the system housing and the outer ring of the circumferentially stacked piezoelectric damping ring are interference-fitted; the inner ring of the circumferentially stacked piezoelectric damping ring is interference-fitted with the bearing.

[0013] Furthermore, the variable impedance shunt circuit module includes: two parallel RLC circuits, a microcontroller, a vibration sensing module, and a signal processing unit; the vibration sensing module, the signal processing unit, and the microcontroller are connected; the microcontroller is connected to the two RLC circuits, and the total output of the piezoelectric stack is connected to the two RLC circuits respectively.

[0014] This invention also provides a circumferential stacked piezoelectric shunt vibration reduction method with variable impedance adapted to vibration characteristics, specifically including the following steps: S1, perform device initialization and parameter calibration, and measure the vibration acceleration range under rated operating conditions. ,Will As a threshold for vibration amplitude The sampling frequency of the vibration signal is set as the peak-to-peak value threshold. Initialize the RLC parameters of the variable impedance shunt circuit and set the initial resistance. Initial inductance Initial capacitance .

[0015] S2, Real-time acquisition of the original vibration signal sequence of the transmission system housing. The amplitude range of vibration acceleration is The original signal is preprocessed by using a Butterworth filter to remove high-frequency noise and zero-mean normalization to eliminate the DC component, resulting in the preprocessed vibration signal. ;Simultaneously acquire the output voltage signal of the piezoelectric stack blocks connected in parallel in the circumferentially stacked piezoelectric damping ring. The effective value of the output voltage under rated operating conditions is U p0-rms This is used for precise matching of subsequent resistance parameters; S3, Time-frequency domain feature extraction of vibration signals, including: amplitude, peak-to-peak value. Effective voltage value, characteristic frequency identification, and piezoelectric voltage corresponding to the characteristic frequency; S4, defines the time-domain state index as Define low-frequency state indicators as Define high-frequency state indicators as ,in, , These represent the voltage amplitudes corresponding to the low-frequency and high-frequency characteristic frequencies under real-time operating conditions. , These are the reference voltages corresponding to the low-frequency and high-frequency characteristic frequencies under rated operating conditions, respectively; the first state is defined as: and and The piezoelectric energy output is stable, the vibration is within the rated range, and the system is in a normal vibration state; the second state is defined as: and Low-frequency vibrations cause an increase in electrical energy, while other frequency bands remain normal; the system is in a low-frequency dominant vibration state. The third state is defined as: and High-frequency vibrations cause an increase in electrical energy, while other frequency bands remain normal; the system is in a high-frequency dominant vibration state; the fourth state is defined as follows: and and Multi-frequency vibrations cause an increase in electrical energy, and the system is in a state of combined excessive vibration. S5, the microcontroller dynamically adjusts the RLC parameter combination of the variable impedance shunt circuit based on the vibration state determination result and the rated operating parameters. S6, after the system completes parameter adjustment and power dissipation, the vibration sensing module continues to collect vibration signals, repeating steps S2~S4 to obtain the current peak-to-peak value of vibration acceleration after vibration reduction. To assess the current vibration reduction effect, the formula for calculating the time-domain vibration reduction rate is: ; like If the value is ≥ 20%, the current variable impedance parameter combination is maintained; if the requirement is not met, or the vibration state changes, step S5 is performed to rematch the parameters and iteratively optimize until the target is met; steps S2~S6 are continuously cyclical to achieve real-time adaptive response to the vibration of the transmission system under varying operating conditions.

[0016] Furthermore, step S5 specifically includes: For the first state, the parameters of the two RLC circuits remain at their initial settings to keep the system in a stable state, adapting to rated and small-amplitude fluctuation vibration conditions; For the second state, the inductance of both RLC circuits is increased to make the resonant frequency of the RLC circuit close to the low-frequency characteristic frequency. Consistent; according to the resonant frequency formula, keeping the capacitance constant, the target inductance... The calculation formula is: ; Simultaneously increase the resistance value, target resistance The calculation formula is: ; For the third state, both RLC circuits reduce their capacitance to make the resonant frequency of the RLC circuit close to the high-frequency characteristic frequency. Consistent; according to the resonant frequency formula, keeping the inductance constant, the target capacitance... The calculation formula is: ; Simultaneously increase the resistance value, target resistance The calculation formula is: ; For the fourth state, the first branch of the two RLC circuits is a low-frequency adaptation branch, and the RLC parameters are set in the same way as in the second state; the second branch of the two RLC circuits is a high-frequency adaptation branch, and the RLC parameters are set in the same way as in the third state.

[0017] The present invention has the following beneficial effects: 1. The wedge spring and the circumferentially stacked piezoelectric arrangement designed in this invention can efficiently convert the radial vibration of the shaft segment into circumferential compression of the piezoelectric stack, greatly improving the conversion efficiency of mechanical energy to electrical energy.

[0018] 2. By sensing changes in the vibration characteristics of the system in real time and dynamically adjusting the impedance parameter combination of the shunt circuit, the present invention significantly improves the adaptability of the device to complex vibration conditions with varying operating conditions and multi-source excitation.

[0019] 3. This invention proposes a dual-branch frequency division adaptation strategy for composite excessive vibration states, which can effectively suppress low-frequency and high-frequency components in vibration at the same time, and broaden the vibration reduction frequency bandwidth. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 A schematic diagram of the operation of the circumferentially stacked piezoelectric shunt vibration reduction device of the present invention is shown.

[0021] Figure 2 A structural diagram of the circumferentially stacked piezoelectric shunt vibration damping device of the present invention is shown.

[0022] Figure 3 It shows Figure 2 A magnified view of the details at point A.

[0023] Figure 4 A schematic diagram of the outer ring structure of the present invention is shown.

[0024] Figure 5 The diagram shows the working principle of the variable impedance shunt circuit module and the vibration sensing module.

[0025] Figure 6 The working principle diagram of the circumferentially stacked piezoelectric vibration damping ring is shown.

[0026] Figure 7 This is a schematic diagram illustrating the working principle of a single set of wedge springs and piezoelectric stacked blocks.

[0027] The descriptions of the figures marked with the above reference numerals are as follows: 1. Circumferentially stacked piezoelectric vibration damping rings; 11. Inner ring; 111. Inner ring groove; 12. Outer ring; 121. Outer ring groove; 13. Mounting bracket; 14. Preload screw; 15. Floating gap; 2. Piezoelectric stacked block; 3. Wedge spring; 31. Arc groove; 4. Variable impedance shunt circuit module; 41. Digital potentiometer; 42. Varactor diode; 43. Magnetic core adjustable inductor; 44. Microcontroller; 45. Current transformer; 46. Operational amplifier; 5. Shaft section to be damped; 6. Bearing; 71. Vibration sensing module; 72. Signal processing unit; 100. System housing. Detailed Implementation

[0028] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1 like Figure 1 and Figure 2 The circumferential stacked piezoelectric shunt vibration damping device with variable impedance adapted to vibration characteristics includes: a circumferential stacked piezoelectric damping ring 1, piezoelectric stacked blocks 2, wedge springs 3, and a variable impedance shunt circuit module 4. The piezoelectric stacked blocks 2 and wedge springs 3 are arranged alternately on the mounting bracket 13 of the circumferential stacked piezoelectric damping ring 1. The shaft section 5 to be damped is sleeved on the inner side of the circumferential stacked piezoelectric damping ring 1 through bearings 6. Multiple piezoelectric stacked blocks 2 are connected in parallel. The variable impedance shunt circuit module 4 is connected to the total output of the piezoelectric stacked blocks 2.

[0030] Specifically, such as Figure 2 and Figure 4 As shown, the circumferentially stacked piezoelectric vibration damping ring includes an inner ring 11, an outer ring 12, and a mounting bracket 13. The mounting bracket is provided between the inner ring and the outer ring. The mounting bracket 13 has a double-layered mounting groove. The piezoelectric stacked block 2 and the wedge spring 3 are arranged alternately in the mounting groove. The inner ring groove 111 is uniformly provided on the outer side wall of the inner ring, and the outer ring groove 121 is uniformly provided on the inner side wall of the outer ring. The end face of the small end of the wedge spring 3 is engaged in the inner ring groove 111, and the end face of the large end of the wedge spring 3 is engaged in the outer ring groove. The preload is applied to the wedge spring by the preload screw 14 on the outer ring, so that the wedge spring is in a semi-compressed state.

[0031] The inner and outer ring grooves respectively hold the two ends of the wedge spring. The inner ring groove is fixedly connected to the wedge spring, while the outer ring groove is only in contact with the wedge spring and can be separated. After being subjected to the preload thrust of the preload screw, an extremely small, almost imperceptible separation occurs. A preload screw is located at the position of the outer ring groove. During assembly, a moderate preload force needs to be applied to the wedge spring through the preload screw, so that the wedge spring is in a semi-compressed state. At this point, the wedge spring is positioned between the inner and outer rings, and the outer ring is fixed to the system housing 100. Furthermore, because the wedge spring is compressible or anti-loosening, the inner ring can float within a small displacement range. This floating corresponds to the slight vibration of the shaft, since the shaft, bearing, and inner ring are fixedly connected by an interference fit. The outer diameter of the mounting bracket is the same as the inner diameter of the outer ring, which is just enough to install the outer ring onto the mounting bracket, and the outer diameter of the mounting bracket is fixedly connected to the outer ring; the inner diameter of the mounting bracket is slightly larger than the outer diameter of the inner ring, so that there is a gap between the inner ring and the mounting bracket. This gap is used to allow the inner ring to make a small displacement range.

[0032] Finally, the piezoelectric stack is fixed on the mounting bracket, and the circumferentially compressed working surface of the piezoelectric stack contacts the side of the wedge spring. As the wedge spring compresses and relaxes, the piezoelectric stack is compressed and relaxed. During this process, a small relative displacement and friction will occur between the side of the wedge spring and the working surface of the piezoelectric stack.

[0033] Specifically, the two working surfaces of the piezoelectric stack 2 along the compression direction abut against the two adjacent wedge springs, respectively.

[0034] Specifically, the piezoelectric stack 2 is composed of multiple piezoelectric ceramic sheets stacked in series, and the non-working surface of the piezoelectric stack 2 is bonded to the mounting bracket with epoxy adhesive.

[0035] Specifically, multiple arc-shaped grooves 31 are evenly opened on the large end of the wedge spring 3. The contact surface between the wedge spring 3 and the piezoelectric stack 2 is a wedge-shaped working surface. The opening of the arc-shaped groove 31 is located on the wedge-shaped working surface of the wedge spring 3. The wedge spring 3 generates radial tension and compression through the arc-shaped groove 31, which squeezes the piezoelectric stack 2 on both sides of the wedge spring 3.

[0036] like Figure 2 , Figure 6 and Figure 7 As shown, the radial compression of the wedge spring is achieved through the two-stage flexible hinge structure formed by the two arc-shaped grooves 31; the wedge-shaped working surface converts the radial vibration of the shaft section to be damped into circumferential vibration, while reducing the displacement of the vibration excitation and amplifying its force, so as to adapt to the inherent characteristics of piezoelectric materials with strong compressive strength and small deformation. Figure 6 The stress and deformation trends of each group of wedge springs and piezoelectric stack blocks are shown when the inner ring is subjected to displacement excitation δx. Figure 7 The stress and deformation trends of the wedge spring and piezoelectric stack block are shown respectively when the inner ring of the damping ring is subjected to radial and circumferential excitation from the shaft segment.

[0037] Specifically, such as Figure 3 As shown, a floating gap of 15 is left between the mounting bracket and the inner ring. The floating gap provides displacement space for the vibration of the shaft section to be damped and the compression of the wedge spring.

[0038] Specifically, it also includes: a vibration sensing module 71, which is located on the system housing and is used to detect vibration signals on the system housing. The system housing is sleeved on the outer side of the outer ring of the circumferentially stacked piezoelectric damping ring, and the system housing and the outer ring of the circumferentially stacked piezoelectric damping ring are interference-fitted; the inner ring of the circumferentially stacked piezoelectric damping ring is interference-fitted with the bearing.

[0039] like Figure 5As shown, the variable impedance shunt circuit module 4 of this invention is connected to the total output of the piezoelectric stack 2. It has two parallel RLC circuits with identical structures and components. The parallel RLC circuit includes three impedance components: a digital potentiometer 41, a varactor diode 42, and a magnetic core adjustable inductor 43. Based on the real-time vibration characteristics of the transmission system, the microcontroller 44 adjusts the combination of the three impedance parameters—resistance R, capacitance C, and inductance L—that is, adjusts the three impedance components: the digital potentiometer 41, the varactor diode 42, and the magnetic core adjustable inductor 43, to achieve a better vibration reduction effect. The total output of the piezoelectric stack 2 is connected to the microcontroller 44 through a current transformer 45. The parallel RLC circuit also includes an operational amplifier 46 to amplify the voltage at the input of the piezoelectric stack.

[0040] Specifically, the variable impedance shunt circuit module includes: two parallel RLC circuits, a microcontroller, a vibration sensing module, and a signal processing unit; the vibration sensing module, signal processing unit, and microcontroller are connected; the microcontroller is connected to the two RLC circuits, and the total output of the piezoelectric stack 2 is connected to both RLC circuits. For example... Figure 5 As shown, the vibration sensing module 71 is used to collect the vibration acceleration signal of the transmission system housing 100; the signal processing unit 72 performs time-frequency domain analysis on the vibration acceleration signal to determine the vibration characteristics of the transmission system; the microcontroller 44 matches the optimal impedance parameters in real time based on the vibration characteristics and adjusts the three impedance elements of the variable impedance shunt circuit module 4.

[0041] Example 2 A circumferential stacked piezoelectric shunt vibration reduction method with variable impedance adapted to vibration characteristics specifically includes the following steps: S1, perform device initialization and parameter calibration, and measure the vibration acceleration range under rated operating conditions. ,Will As a threshold for vibration amplitude The sampling frequency of the vibration signal is set as the peak-to-peak value threshold. Initialize the RLC parameters of the variable impedance shunt circuit and set the initial resistance. Initial inductance Initial capacitance ; S2, Vibration signal acquisition and preprocessing. The original vibration signal sequence x(t) of the transmission system housing is acquired in real time, with the vibration acceleration amplitude ranging from -a(t) to a(t). m / s 2 The original signal is preprocessed by using a Butterworth filter to remove high-frequency noise and eliminating the DC component through zero-mean normalization to obtain the preprocessed vibration signal x1(t); the output voltage signal U of the piezoelectric stack blocks (2 (2) connected in parallel in the circumferential stacked piezoelectric damping ring is simultaneously acquired. p(t), whose amplitude is positively correlated with the amplitude of vibration acceleration, and the effective value of the output voltage under rated operating conditions is U. p0-rms This is used for precise matching of subsequent resistance parameters; S3, Time-Frequency Domain Feature Extraction of Vibration Signals. Firstly, vibration amplitude extraction: calculating the amplitude A of the preprocessed vibration signal x1(t) in the statistical time domain. The calculation formula is as follows: ; Secondly, based on the difference between the peaks and troughs of the vibration wave, the peak-to-peak value A of the original vibration acceleration is calculated. pp for: ; Third, statistical analysis of the piezoelectric output voltage, based on the output voltage signal U. p (t), calculate the effective value of the voltage: ; Fourth, characteristic frequency identification: a fast Fourier transform is performed on the preprocessed vibration signal x'(t) to obtain the power spectral density signal. By finding the peak point of the power spectral density, the low-frequency characteristic frequency f that dominates the frequency domain is determined. L-peak and high-frequency characteristic frequency f H-peak ; Fifth, the piezoelectric voltage corresponding to the characteristic frequency is extracted. Based on the correlation characteristics between the output voltage and the vibration frequency, the reference voltage U corresponding to the low-frequency and high-frequency characteristic frequencies under rated operating conditions is extracted. L-0 U H-0 The voltage amplitude U corresponding to the low-frequency and high-frequency characteristic frequencies under real-time operating conditions. L U H This provides a basis for impedance matching in different frequency bands.

[0042] S4, Feature Fusion and State Determination. First, the state parameters are normalized based on the rated parameters to define the evaluation index of the vibration state. Among them, the time-domain state index is defined as follows: Define low-frequency state indicators as Define high-frequency state indicators as Secondly, based on the combination of various indicators, the current vibration state is determined. There are four typical states, the first being: and and The piezoelectric energy output is stable, the vibration is within the rated range, and the system is in a normal vibration state; Second state: and Low-frequency vibrations cause an increase in electrical energy, while other frequency bands remain normal; the system is in a low-frequency dominant vibration state; third state: and High-frequency vibration causes an increase in electrical energy, while other frequency bands remain normal; the system is in a high-frequency dominant vibration state; fourth state: and and Multi-frequency vibrations caused a significant increase in electrical energy, and the system was in a state of combined excessive vibration.

[0043] S5, Variable Impedance Parameter Matching Strategy. Based on the vibration state determination, the microcontroller dynamically adjusts the RLC parameter combination of the variable impedance shunt circuit using rated operating parameters as a reference. By adjusting the circuit's resonant frequency to match the vibration characteristic frequency, efficient energy capture is ensured; the resistance is adjusted to increase synchronously with the energy, ensuring stable energy dissipation. S6, Closed-loop feedback and continuous optimization. After the system completes parameter adjustment and power dissipation, the vibration sensing module continues to collect vibration signals, repeating steps S2~S4 to obtain the current peak-to-peak value of vibration acceleration after vibration reduction. To assess the current vibration reduction effect, the formula for calculating the time-domain vibration reduction rate is: ; like If the vibration rate is ≥ 20% (or other reasonable range), maintain the current variable impedance parameter combination; if the requirements are not met, or the vibration state changes, proceed to step S5 to rematch the parameters and iteratively optimize until the target is met. Continuously cycle through steps S2~S6 to achieve real-time adaptive response to the variable operating condition vibration of the transmission system. Specifically, step S5 is as follows: For the first state, i.e., the normal vibration state, the dual branches maintain the reference parameters. The parameters of the two RLC circuits remain at their initial settings, keeping the system in a stable state and adapting to rated and small-amplitude fluctuation vibration conditions.

[0044] For the second state, namely the low-frequency dominant vibration state, two RLC circuits are adapted to meet the low-frequency requirements. The inductance of both RLC circuits is increased so that the resonant frequency of the RLC circuit is close to the low-frequency characteristic frequency. Consistent. According to the resonant frequency formula, keeping the capacitance constant, the target inductance... The calculation formula is: ; Simultaneously increase the resistance value, target resistance The calculation formula is: ; For the third state, namely the high-frequency dominant vibration state, a dual-branch design is adopted to meet high-frequency requirements. The capacitance of both branches is reduced to bring the resonant frequency of the RLC circuit closer to the high-frequency characteristic frequency. Consistent. According to the resonant frequency formula, keeping the inductance constant, the target capacitance... The calculation formula is: ; Simultaneously increase the resistance value, target resistance R target The calculation formula is: ; For the fourth state, namely the combined excessive vibration state, a dual-branch frequency band adaptation strategy is adopted. Specifically, the first branch of the two RLC circuits... Figure 5 Branch 1 in the circuit is the low-frequency adaptation branch, and its RLC parameters are set in the same way as in the second state; the first branch of the two RLC circuits, namely... Figure 5 Branch 2 in the diagram is a high-frequency adaptation branch, and its RLC parameters are set in the same way as in the third state. The two branches are matched to the low-frequency and high-frequency characteristic frequencies respectively, and the two branches work together to achieve broadband suppression of composite vibrations.

[0045] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A circumferentially stacked piezoelectric shunt vibration damping device with variable impedance adapted to vibration characteristics, characterized in that, include: The circumferential stacked piezoelectric vibration damping ring (1), piezoelectric stacked blocks (2), wedge springs (3) and variable impedance shunt circuit module (4) are arranged alternately on the mounting bracket (13) of the circumferential stacked piezoelectric vibration damping ring (1). The shaft section (5) to be damped is sleeved on the inner side of the circumferential stacked piezoelectric vibration damping ring (1) through the bearing (6). Multiple piezoelectric stacked blocks (2) are connected in parallel. The variable impedance shunt circuit module (4) is connected to the total output of the piezoelectric stacked blocks (2).

2. The circumferentially stacked piezoelectric shunt vibration damping device with variable impedance adapted to vibration characteristics as shown in claim 1, characterized in that, The circumferential stacked piezoelectric vibration damping ring (1) includes an inner ring (11), an outer ring (12), and a mounting bracket (13). The mounting bracket (13) is provided between the inner ring (11) and the outer ring (12). The mounting bracket (13) has a double-layer mounting groove. The piezoelectric stacked block (2) and the wedge spring (3) are arranged alternately in the mounting groove. The inner ring groove (111) is uniformly provided on the outer side wall of the inner ring (11), and the outer ring groove (121) is uniformly provided on the inner side wall of the outer ring (12). The end face of the small end of the wedge spring (3) is engaged in the inner ring groove (111), and the end face of the large end of the wedge spring (3) is engaged in the outer ring groove (121). The preload is applied to the wedge spring (3) by the preload screw (14) on the outer ring (12), so that the wedge spring (3) is in a semi-compressed state.

3. The circumferentially stacked piezoelectric shunt vibration damping device with variable impedance adapted to vibration characteristics as shown in claim 1, characterized in that, The two working surfaces of the piezoelectric stack (2) along the compression direction abut against the two adjacent wedge springs (3).

4. A circumferentially stacked piezoelectric shunt vibration damping device with variable impedance adapted to vibration characteristics as shown in claim 1, characterized in that, The piezoelectric stack (2) is made of multiple piezoelectric ceramic sheets stacked in series. The non-working surface of the piezoelectric stack (2) is bonded to the mounting bracket (13) with epoxy adhesive.

5. A circumferentially stacked piezoelectric shunt vibration damping device with variable impedance adapted to vibration characteristics as shown in claim 1, characterized in that, Multiple arc-shaped grooves (31) are evenly opened on the large end of the wedge spring (3). The contact surface between the wedge spring (3) and the piezoelectric stack (2) is a wedge-shaped working surface. The opening of the arc-shaped groove (31) is located on the wedge-shaped working surface of the wedge spring (3). The wedge spring (3) generates radial tension and compression through the arc-shaped groove (31), which squeezes the piezoelectric stack (2) on both sides of the wedge spring (3).

6. A circumferentially stacked piezoelectric shunt vibration damping device with variable impedance adapted to vibration characteristics as shown in claim 1, characterized in that, The mounting bracket (13) and the inner ring have a floating gap (15), which provides displacement space for the vibration of the shaft section to be damped and the compression of the wedge spring (3).

7. A circumferentially stacked piezoelectric shunt vibration damping device with variable impedance adapted to vibration characteristics as shown in claim 2, characterized in that, Also includes: Vibration sensing module (71) is located on the system housing (100) and is used to detect vibration signals on the system housing (100). The system housing (100) is sleeved on the outer ring (12) of the circumferential stacked piezoelectric damping ring (1). The system housing (100) and the outer ring (12) of the circumferential stacked piezoelectric damping ring (1) are interference-fitted. The inner ring (11) of the circumferential stacked piezoelectric damping ring (1) is interference-fitted with the bearing (6).

8. A circumferentially stacked piezoelectric shunt vibration damping device with variable impedance adapted to vibration characteristics as shown in claim 1, characterized in that, The variable impedance shunt circuit module (4) includes: two parallel RLC circuits, a microcontroller (44), a vibration sensing module (71), and a signal processing unit (72); the vibration sensing module (71), the signal processing unit (72), and the microcontroller (44) are connected; the microcontroller (44) is connected to the two RLC circuits, and the total output of the piezoelectric stack block (2) is connected to the two RLC circuits respectively.

9. A circumferentially stacked piezoelectric shunt vibration reduction method with variable impedance adapted to vibration characteristics, utilizing the device described in any one of claims 1-8, characterized in that, Specifically, the steps include the following: S1, perform device initialization and parameter calibration, and measure the vibration acceleration range under rated operating conditions. ,Will As a threshold for vibration amplitude The sampling frequency of the vibration signal is set as the peak-to-peak value threshold. Initialize the RLC parameters of the variable impedance shunt circuit and set the initial resistance. Initial inductance Initial capacitance ; S2, Real-time acquisition of the original vibration signal sequence of the transmission system housing (100) The amplitude range of vibration acceleration is The original signal is preprocessed by using a Butterworth filter to remove high-frequency noise and zero-mean normalization to eliminate the DC component, resulting in the preprocessed vibration signal. ;Synchronously acquire the output voltage signal of the piezoelectric stack block (2) connected in parallel in the circumferential stacked piezoelectric damping ring. The effective value of the output voltage under rated operating conditions is U p0-rms This is used for precise matching of subsequent resistance parameters; S3, Time-frequency domain feature extraction of vibration signals, including: amplitude, peak-to-peak value. Effective voltage value, characteristic frequency identification, and piezoelectric voltage corresponding to the characteristic frequency; S4, defines the time-domain state index as Define low-frequency state indicators as Define high-frequency state indicators as ,in, , These represent the voltage amplitudes corresponding to the low-frequency and high-frequency characteristic frequencies under real-time operating conditions. , These are the reference voltages corresponding to the low-frequency and high-frequency characteristic frequencies under rated operating conditions, respectively; the first state is defined as: and and The piezoelectric energy output is stable, the vibration is within the rated range, and the system is in a normal vibration state; the second state is defined as: and Low-frequency vibrations cause an increase in electrical energy, while other frequency bands remain normal; the system is in a low-frequency dominant vibration state. The third state is defined as: and High-frequency vibrations cause an increase in electrical energy, while other frequency bands remain normal; the system is in a high-frequency dominant vibration state; the fourth state is defined as follows: and and Multi-frequency vibrations cause an increase in electrical energy, and the system is in a state of combined excessive vibration. S5, the microcontroller dynamically adjusts the RLC parameter combination of the variable impedance shunt circuit based on the vibration state determination result and the rated operating parameters. S6, after the system completes parameter adjustment and power dissipation, the vibration sensing module continues to collect vibration signals, repeating steps S2~S4 to obtain the current peak-to-peak value of vibration acceleration after vibration reduction. To assess the current vibration reduction effect, the formula for calculating the time-domain vibration reduction rate is: ； like If the value is ≥ 20%, the current variable impedance parameter combination is maintained; if the requirement is not met, or the vibration state changes, step S5 is performed to rematch the parameters and iteratively optimize until the target is met; steps S2~S6 are continuously cyclical to achieve real-time adaptive response to the vibration of the transmission system under varying operating conditions.

10. The circumferential stacked piezoelectric current shunt vibration reduction method with variable impedance adapted to vibration characteristics according to claim 9, characterized in that, Step S5 is as follows: For the first state, the parameters of the two RLC circuits remain at their initial settings to keep the system in a stable state, adapting to rated and small-amplitude fluctuation vibration conditions. For the second state, the inductance of both RLC circuits is increased to make the resonant frequency of the RLC circuit close to the low-frequency characteristic frequency. Consistent; According to the resonant frequency formula, keeping the capacitance constant, the target inductance... The calculation formula is: ； Simultaneously increase the resistance value, target resistance The calculation formula is: ； For the third state, both RLC circuits reduce their capacitance to make the resonant frequency of the RLC circuit close to the high-frequency characteristic frequency. Consistent; According to the resonant frequency formula, keeping the inductance constant, the target capacitance... The calculation formula is: ； Simultaneously increase the resistance value, target resistance The calculation formula is: ； For the fourth state, the first branch of the two RLC circuits is a low-frequency adaptation branch, and the RLC parameters are set in the same way as in the second state; the second branch of the two RLC circuits is a high-frequency adaptation branch, and the RLC parameters are set in the same way as in the third state.

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