A rotating machinery fault diagnosis system and method

Abstract

This application relates to the field of rotating machinery fault diagnosis technology, and more particularly to a rotating machinery fault diagnosis system and method. The rotating machinery fault diagnosis system includes a microcontroller and a multi-degree-of-freedom piezoelectric beam device mounted on the rotating machinery. The multi-degree-of-freedom piezoelectric beam device includes an outer beam assembly and at least one inner beam assembly, which are respectively connected to the microcontroller. The outer beam assembly is configured to collect vibration signals from the rotating machinery, and the inner beam assembly is configured to capture the vibration energy of the rotating machinery to power the microcontroller. The microcontroller is configured to perform fault diagnosis on the rotating machinery based on the vibration signals to obtain fault analysis results. This system not only achieves self-powered, maintenance-free operation but also improves the accuracy of fault diagnosis for rotating machinery.

Description

Technical Field

[0001] This application relates to the field of rotating machinery fault diagnosis technology, and in particular to a rotating machinery fault diagnosis system and method. Background Technology

[0002] In industrial production systems, rotating machinery serves as core power equipment, and its operational stability directly impacts overall production safety and efficiency. Bearings, as critical components of rotating machinery, have a decisive influence on equipment reliability due to their health condition.

[0003] Therefore, how to monitor the condition of bearings and diagnose faults in order to avoid catastrophic equipment damage and downtime losses is a technical problem that urgently needs to be solved. Summary of the Invention

[0004] Based on this, this application provides a rotating machinery fault diagnosis system and method, which can achieve self-powered, maintenance-free operation, and improve the accuracy of fault diagnosis of rotating machinery.

[0005] In a first aspect, this application provides a rotating machinery fault diagnosis system, which includes: microcontroller; A multi-degree-of-freedom piezoelectric beam device is installed on rotating machinery; the multi-degree-of-freedom piezoelectric beam device includes an outer beam assembly and at least one inner beam assembly, and the outer beam assembly and the inner beam assembly are respectively connected to a microcontroller; The outer beam assembly is configured to collect vibration signals from rotating machinery. The inner beam assembly is configured to capture the vibrational energy of rotating machinery to power the microcontroller; The microcontroller is configured to perform fault diagnosis on rotating machinery based on vibration signals to obtain fault analysis results of the rotating machinery.

[0006] In one embodiment, the outer beam assembly includes an outer beam body and an outer beam piezoelectric sheet, and the inner beam assembly includes an inner beam body and an inner beam piezoelectric sheet. Among them, the piezoelectric sheet of the outer beam is installed on the outer beam body and is configured to output vibration signal when the outer beam body vibrates with the rotating machinery; The piezoelectric element of the inner beam is located on the inner beam body and is configured to output vibration energy when the inner beam body vibrates with the rotating machinery.

[0007] In one embodiment, the multi-degree-of-freedom piezoelectric beam device further includes a base, and the outer beam body includes a first outer beam body and a second outer beam body; The inner beam body is located between the first outer beam body and the second outer beam body. The first outer beam body, the second outer beam body, and the inner beam body are all mounted on the base to form a plane.

[0008] In one embodiment, the base is provided with a support portion, a first connecting portion, and a second connecting portion; Wherein, one end of the supporting part is connected to one end of the first outer beam body, the other end of the supporting part is connected to one end of the second outer beam body, the other end of the first outer beam body is connected to the first connecting part, and the other end of the second outer beam body is connected to the second connecting part; or / and Multiple inner beam components are provided between the first outer beam body and the second outer beam body, and the multiple inner beam components are arranged in an array.

[0009] In one embodiment, the outer beam assembly further includes an outer beam magnet, the inner beam assembly further includes an inner beam magnet, and the base is provided with a first magnet and a second magnet; Among them, one end of the outer beam magnet is connected to one end of the first outer beam body, the other end of the outer beam magnet is connected to the other end of the second outer beam body, and the inner beam magnet is installed on the inner beam body. The outer beam magnet is located between the first magnet and the inner beam magnet, and the inner beam magnet is located between the outer beam magnet and the second magnet; The near ends of two adjacent magnets are both magnetic poles of the same name, so as to create a magnetic repulsion between the magnets.

[0010] In one embodiment, the system further includes signal conditioning and sampling circuitry; The signal conditioning and sampling circuit is connected to the outer beam assembly and the microcontroller at its two ends, respectively, and is configured to process the vibration signal output from the outer beam assembly to output a digital signal to the microcontroller. The microcontroller is configured to perform fault diagnosis on the rotating machinery based on the digital signal to obtain the fault analysis results of the rotating machinery; or / and, The system also includes energy management and storage circuitry; The energy management and storage circuit is connected to the inner beam assembly and the microcontroller at its two ends, respectively, and is configured to convert the vibration energy output by the inner beam assembly into power supply for the microcontroller.

[0011] In one embodiment, the signal conditioning and sampling circuit includes a high input impedance buffer unit, an analog filtering unit, and a bias / limiting protection unit; Among them, the two ends of the high input impedance buffer unit are respectively connected to the outer beam assembly and one end of the analog filter unit, and the two ends of the bias / limiting protection unit are respectively connected to the other end of the analog filter unit and the microcontroller. The high input impedance buffer unit is configured to perform impedance transformation and isolation buffering on the vibration signal to obtain the vibration signal after impedance transformation and isolation buffering. The analog filtering unit is configured to filter the vibration signal after impedance transformation and isolation buffering to obtain the filtered vibration signal. The bias / limiting protection unit is configured to perform DC bias adjustment and amplitude limiting on the filtered vibration signal to obtain the vibration signal after DC bias adjustment and amplitude limiting. The microcontroller is configured to perform fault diagnosis on rotating machinery based on vibration signals after DC bias adjustment and amplitude limiting, in order to obtain fault analysis results for the rotating machinery; or / and, The energy management and storage circuit includes a rectifier unit, an energy / charging management unit, an energy storage unit, and a buck-boost unit; Among them, one end of the rectifier unit is connected to the inner beam assembly, the other end of the rectifier unit is connected to the first end of the energy / charging management unit, the second end of the energy / charging management unit is connected to one end of the energy storage unit, the other end of the energy storage unit is connected to one end of the buck-boost unit, and the other end of the buck-boost unit is connected to the microcontroller. The rectifier unit is configured to convert the vibration energy output from the inner beam assembly into DC power. The energy / charging management unit is configured to manage the charging of the energy storage unit based on a DC power supply; The energy storage unit is configured to output peak power; the buck-boost unit is configured to supply power to the microcontroller based on the peak power output.

[0012] In one embodiment, the energy management storage circuit further includes a power gating unit; One end of the power gating unit is connected to the third end of the energy / charging management unit, and the other end of the power gating unit is connected to the microcontroller. The power gating unit is configured to control the energy / charging management unit based on the control signals output by the microcontroller, so as to control the operating status of the rotating machinery fault diagnosis system.

[0013] Secondly, this application also provides a method for diagnosing rotating machinery faults, which is applied to the rotating machinery fault diagnosis system provided in the first aspect. The method includes: With the internal beam assembly used to power the microcontroller, the vibration signal is preprocessed to obtain the preprocessed vibration signal. The preprocessed vibration signal is input into a preset diagnostic identification model to obtain the fault analysis results of the rotating machinery; The fault analysis results are sent to the terminal device and displayed visually.

[0014] In one embodiment, the method further includes: When the vibration energy output from the inner beam assembly is converted into power for the microcontroller using an energy management storage circuit, the microcontroller is activated when the power supply voltage of the energy management storage circuit reaches a preset start-up threshold. When the supply voltage drops to a preset cutoff threshold, the control energy management storage circuit stops supplying power to the microcontroller, causing the microcontroller to enter a sleep state.

[0015] The rotating machinery fault diagnosis system provided in this application includes a microcontroller and a multi-degree-of-freedom piezoelectric beam device mounted on the rotating machinery. The multi-degree-of-freedom piezoelectric beam device includes an outer beam assembly and at least one inner beam assembly, which are respectively connected to the microcontroller. The outer beam assembly is configured to collect vibration signals from the rotating machinery, and the inner beam assembly is configured to capture the vibration energy of the rotating machinery to power the microcontroller. The microcontroller is configured to perform fault diagnosis on the rotating machinery based on the vibration signals to obtain fault analysis results of the rotating machinery. This system not only achieves self-powered, maintenance-free operation but also improves the accuracy of fault diagnosis of rotating machinery. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a first schematic block diagram of a rotating machinery fault diagnosis system provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of the multi-degree-of-freedom piezoelectric beam device provided in the embodiments of this application; Figure 3 This is a second schematic block diagram of a rotating machinery fault diagnosis system provided in an embodiment of this application; Figure 4 This is a functional block diagram of a dual-channel circuit provided in an embodiment of this application; Figure 5 This is a first flowchart illustrating the rotating machinery fault diagnosis method provided in an embodiment of this application; Figure 6 This is a schematic diagram of the second process of the rotating machinery fault diagnosis method provided in the embodiments of this application.

[0018] Figure label: 1. Rotating machinery fault diagnosis system; 10. Multi-degree-of-freedom piezoelectric beam device; 100. Outer beam assembly; 110. First outer beam body; 120. Second outer beam body; 130. Outer beam piezoelectric sheet; 140. Outer beam magnet; 200. Inner beam assembly; 210. Inner beam body; 220. Inner beam piezoelectric sheet; 230. Inner beam magnet; 300. Base; 301. First magnet; 302. Second magnet; 20. Microcontroller; 30. Signal conditioning and sampling circuit; 310. High input impedance buffer unit; 320. Analog filtering unit; 330. Bias / limiting protection unit; 40. Energy management and storage circuit; 410. Rectifier unit; 420. Energy / charging management unit; 430. Energy storage unit; 440. Buck-boost unit. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0021] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0022] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0023] Furthermore, in this application, unless otherwise explicitly specified or limited in the embodiments, the terms "installation," "connection," "joining," and "fixing" appearing in the embodiments should be interpreted broadly. For example, a connection can be a fixed connection, a detachable connection, or an integral part; it can also be a mechanical connection, an electrical connection, etc. Of course, it can also be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication between two components, or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific implementation.

[0024] In related technologies, rotating machinery is a core power source, and its operational stability directly affects overall production safety and efficiency. As the joint of rotating machinery, the health of rolling bearings directly determines the operational reliability of the equipment. Rolling bearing failure is a major cause of unplanned downtime in rotating machinery. To avoid catastrophic damage and downtime losses to rotating machinery, condition monitoring and fault diagnosis of rolling bearings have become crucial aspects of intelligent manufacturing.

[0025] Traditional bearing monitoring systems primarily rely on a "wired sensor + data acquisition card + host computer" architecture. While this architecture offers excellent signal quality and processing capabilities, it suffers from complex wiring and high installation costs during large-scale deployments. Meanwhile, with the development of wireless sensor network technology, wireless vibration sensors are becoming increasingly common; however, existing wireless nodes generally face a trade-off between power supply lifespan and data bandwidth. Therefore, the monitoring system suffers from the following problems: 1. Most wireless vibration sensors are powered by lithium batteries. In typical industrial applications, the battery life often only lasts for a few months to a year, resulting in huge battery replacement and maintenance costs and environmental pollution from discarded batteries. 2. In order to make accurate diagnosis, the original vibration waveform is usually uploaded to the cloud server for spectrum analysis. However, the volume of high-frequency vibration data is huge. At the same time, in narrowband IoT or congested industrial Wi-Fi environments, transmitting such a large amount of data will cause serious network latency and packet loss. 3. Most piezoelectric vibration energy harvesting devices focus on maximizing energy output and adopt a single-degree-of-freedom cantilever beam structure. Their operating frequency band is narrow and they are only effective near the resonant frequency. At the same time, the most basic piezoelectric vibration energy harvesting device adopts a single-degree-of-freedom (1-DOF) cantilever beam structure. However, its structure is simple and it only has high electromechanical conversion efficiency in an extremely narrow frequency band. Once the environmental vibration frequency, such as the motor speed, fluctuates slightly and deviates from the resonant point, the output power will drop sharply.

[0026] To address the bandwidth issue, two-degree-of-freedom (2-DOF) and multi-degree-of-freedom structures have been proposed. By introducing a second mass block through cutouts or nested beam structures, two similar resonance peaks are generated, thereby covering a wider frequency range.

[0027] However, most two-degree-of-freedom (2-DOF) architectures focus on using the vibrations of both degrees of freedom for energy harvesting, without considering separating one of the degrees of freedom for high-fidelity sensing.

[0028] In summary, there is currently a contradiction between signal integrity and energy extraction when realizing self-powered intelligent nodes. If the same piezoelectric material is used, the impedance matching requirements of the energy extraction circuit are completely opposite to the high input impedance requirements of the sensor, making it impossible to balance high-efficiency charging and high-fidelity signal acquisition. At the same time, system-level energy efficiency optimization is lacking, and there is a lack of a solution that deeply coordinates the physical characteristics of the mechanical structure with the sleep strategy of the electronic system and the computational load of the AI ​​algorithm.

[0029] To address this, this application provides a rotating machinery fault diagnosis system and method. The system includes a microcontroller and a multi-degree-of-freedom piezoelectric beam device mounted on the rotating machinery. The multi-degree-of-freedom piezoelectric beam device includes an outer beam assembly and at least one inner beam assembly, both connected to the microcontroller. The outer beam assembly is configured to collect vibration signals from the rotating machinery, and the inner beam assembly is configured to capture the vibration energy of the rotating machinery to power the microcontroller. The microcontroller is configured to perform fault diagnosis on the rotating machinery based on the vibration signals to obtain fault analysis results. This system not only achieves self-powered, maintenance-free operation but also improves the accuracy of fault diagnosis. Furthermore, this application can collect sufficient energy to drive the microcontroller to complete periodic wake-up, data acquisition, AI inference, and wireless transmission tasks. Utilizing the lightweight neural network built into the microcontroller, complex vibration waveforms are locally converted into simple fault status codes, achieving zero raw data transmission.

[0030] Please see Figure 1 , Figure 1 This is a first schematic block diagram of a rotating machinery fault diagnosis system provided in an embodiment of this application. Figure 1 As shown, this application provides a rotating machinery fault diagnosis system 1, which includes: Microcontroller 20; A multi-degree-of-freedom piezoelectric beam device 10 is installed on a rotating machine. The multi-degree-of-freedom piezoelectric beam device 10 includes an outer beam assembly 100 and at least one inner beam assembly 200. The outer beam assembly 100 and the inner beam assembly 200 are respectively connected to a microcontroller 20. The outer beam assembly 100 is configured to collect vibration signals from rotating machinery. The inner beam assembly 200 is configured to capture the vibrational energy of rotating machinery to power the microcontroller 20; The microcontroller 20 is configured to perform fault diagnosis on rotating machinery based on vibration signals to obtain fault analysis results of the rotating machinery.

[0031] In this embodiment, the microcontroller unit (MCU) 20 is an integrated circuit chip that integrates a central processing unit, memory, timer / counter, and various input / output interfaces. The microcontroller 20 can receive and process data and execute control tasks according to a preset program. In this application, the microcontroller 20 is configured in the rotating machinery fault diagnosis system 1 as the core processing unit, responsible for receiving vibration signals, executing fault diagnosis algorithms, and managing the system's operating status.

[0032] The multi-degree-of-freedom piezoelectric beam device 10 can be understood as a device capable of converting mechanical vibration energy into electrical energy while simultaneously acquiring vibration signals. The multi-degree-of-freedom piezoelectric beam device 10 has two independent or coupled vibration modes, allowing for optimization to meet different functional requirements. The multi-degree-of-freedom piezoelectric beam device 10 is mounted on rotating machinery to sense and utilize the vibrations of the rotating machinery.

[0033] The outer beam assembly 100 can acquire vibration signals from rotating machinery with high fidelity. The outer beam assembly 100 may contain piezoelectric materials that generate electrical charges when subjected to mechanical vibration, thereby outputting electrical signals representing the vibration characteristics.

[0034] The inner beam assembly 200 can efficiently capture the vibrational energy of rotating machinery. The inner beam assembly 200 also contains piezoelectric materials that generate electrical energy under vibration and are used to power other electronic components of the system.

[0035] Vibration signals can be understood as the electrical signals corresponding to the mechanical vibrations generated during the operation of rotating machinery. Vibration signals contain information about the operating status of mechanical components, such as fault characteristics like bearing wear, imbalance, and misalignment.

[0036] Vibration energy can be understood as the energy contained in the mechanical vibrations generated during the operation of rotating machinery. This application utilizes the piezoelectric effect to convert mechanical energy into electrical energy to power the rotating machinery fault diagnosis system 1.

[0037] Fault analysis results can be understood as conclusions about the health status of rotating machinery obtained after fault diagnosis, such as "normal", "inner ring fault", "outer ring fault" or "rolling element fault", etc.

[0038] Specifically, the microcontroller 20 can be a low-power general-purpose microcontroller unit that can be configured to receive vibration signals from the outer beam assembly 100 and execute a preset fault diagnosis algorithm. For example, the microcontroller 20 can perform time-domain or frequency-domain analysis on the acquired vibration signals, such as calculating the root mean square value, peak factor, or performing a fast Fourier transform, to extract fault features.

[0039] The multi-degree-of-freedom piezoelectric beam device 10 can consist of two independent cantilever beam structures, each equipped with a piezoelectric element. The two cantilever beams can be designed with different natural frequencies to respond to different vibration modes. For example, one cantilever beam can be designed with a higher natural frequency for acquiring broadband vibration signals, while the other cantilever beam can be designed with a lower natural frequency for efficient energy harvesting at a specific frequency. The multi-degree-of-freedom piezoelectric beam device 10 is fixed to the surface of the bearing housing, casing, or support structure of rotating machinery by bolts or adhesive to ensure effective sensing of mechanical vibrations.

[0040] The outer beam assembly 100 can be configured to collect vibration signals from rotating machinery.

[0041] As an example, the outer beam assembly 100 may be composed of a cantilever beam made of metal or composite material, with piezoelectric ceramic sheets bonded to its surface or interior. When the rotating machinery vibrates, the cantilever beam vibrates accordingly, and the piezoelectric ceramic sheets generate electrical charges due to deformation, thereby outputting a voltage signal related to the vibration amplitude and frequency, i.e., a vibration signal, which contains information about the operating status of the rotating machinery.

[0042] The inner beam assembly 200 is configured to capture the vibrational energy of rotating machinery to power the microcontroller 20.

[0043] As an example, the inner beam assembly 200 can be constructed from another cantilever beam, on which piezoelectric ceramic sheets are also attached. The structural parameters of the inner beam assembly 200, such as the beam dimensions and the weight of the mass block, can be designed so that its natural frequency is close to the main operating frequency of the rotating machinery, thereby maximizing the strain of the piezoelectric sheets in a resonant state. This efficiently converts mechanical vibration energy into electrical energy, which, after appropriate circuit processing, can provide a stable DC power supply to the microcontroller 20.

[0044] The vibration signal output by the outer beam assembly 100 can be directly connected to the analog-to-digital converter input of the microcontroller 20 for digital sampling. The vibration energy captured by the inner beam assembly 200 is connected to the power input of the microcontroller 20 through an independent power management circuit to provide the microcontroller 20 with the power required for operation, thereby ensuring electrical isolation between the signal acquisition channel and the power supply channel.

[0045] The microcontroller 20 can be configured to perform fault diagnosis on rotating machinery based on vibration signals to obtain fault analysis results of the rotating machinery.

[0046] For example, after receiving a digitized vibration signal, the microcontroller 20 can run a built-in signal processing program, which can then perform operations such as filtering, denoising, and feature extraction on the signal. The extracted features are then compared with preset fault modes to determine the current operating status of the rotating machinery and output corresponding fault analysis results, such as indicating whether the bearing has inner ring damage, outer ring damage, or rolling element damage.

[0047] In this application, the vibration signal acquisition and vibration energy capture functions are decoupled in physical structure and electrically isolated dual channels are used, implemented by the outer beam assembly 100 and the inner beam assembly 200 respectively. The output of the inner beam is connected to the energy management and energy storage unit 430, and the output of the outer beam is connected to the high input impedance signal conditioning and sampling unit. Anti-aliasing filtering and DC bias are configured to adapt to the MCU sampling range, which effectively solves the problems of short power supply life, limited data transmission bandwidth, and contradiction between signal integrity and energy extraction in traditional wireless sensors. This enables self-powered operation, significantly reducing maintenance costs and environmental pollution. At the same time, the microcontroller 20 performs fault diagnosis locally, reducing the amount of raw data transmission, alleviating network bandwidth pressure, and ensuring a balance between high-fidelity signal acquisition and efficient energy capture, thereby improving the reliability and engineering deployability of rotating machinery fault diagnosis.

[0048] The microcontroller 20 samples the signal output from the outer beam assembly 100 and uses DMA to write the data into a circular buffer. The sampling rate and window length are settable, with a sampling rate of approximately 10kHz and a single window of 1024 points. Simultaneously, the window data (x) is standardized (x′=(x-μ) / σ), where (μ,σ) are the mean and standard deviation calculated and fixed during the offline training phase to reduce the impact of amplitude fluctuations on recognition.

[0049] In one embodiment, such as Figure 2 As shown, the outer beam assembly 100 includes an outer beam body and an outer beam piezoelectric sheet 130, and the inner beam assembly 200 includes an inner beam body 210 and an inner beam piezoelectric sheet 220; wherein, the outer beam piezoelectric sheet 130 is disposed on the outer beam body and is configured to output a vibration signal when the outer beam body vibrates with rotating machinery; the inner beam piezoelectric sheet 220 is disposed on the inner beam body 210 and is configured to output vibration energy when the inner beam body 210 vibrates with rotating machinery.

[0050] In this embodiment, the outer beam body can be understood as the main structural body of the outer beam assembly 100 in the multi-degree-of-freedom piezoelectric beam device 10. Its main function is to serve as a carrier for receiving and transmitting vibration signals and to provide an attachment substrate for the outer beam piezoelectric sheet 130.

[0051] The outer beam body can be made of elastic materials, such as stainless steel, aluminum alloy or composite materials, and its geometry can be designed as a cantilever beam, simply supported beam or fixed beam structure to optimize its response characteristics to vibration signals from rotating machinery.

[0052] In addition, the dimensions and material parameters of the outer beam can be tuned according to the vibration frequency range of the target rotating machinery to give it a wider frequency response characteristic, thereby enabling it to capture broadband vibration signals including fault impacts.

[0053] The outer beam piezoelectric element 130 can be understood as a sensing element in the outer beam assembly 100 used to convert mechanical vibration energy into electrical energy, and its output electrical signal is the vibration signal.

[0054] The outer beam piezoelectric sheet 130 can be made of PZT (lead zirconate titanate) ceramic, PVDF (polyvinylidene fluoride) film or piezoelectric composite material, etc., and is firmly set on the surface or inside of the outer beam body by means of bonding, lamination or sintering.

[0055] Meanwhile, the outer beam piezoelectric sheet 130 can adopt a single-layer or multi-layer structure, and its electrode lead-out method can be designed as a two-wire or three-wire system according to the signal acquisition requirements to ensure signal integrity and anti-interference capability.

[0056] This application ensures that the piezoelectric element 130 of the outer beam can directly sense and faithfully reflect the vibration state of the outer beam body by disposing of the outer beam body on the outer beam body and configuring it to output a vibration signal when the outer beam body vibrates with rotating machinery. In this way, a high-fidelity vibration signal is output. The outer beam body acts as a vibration transmission medium, and its vibration directly causes the outer beam piezoelectric element 130 attached to it to deform. The piezoelectric effect converts the deformation into charge, forming a voltage signal.

[0057] Meanwhile, the outer beam piezoelectric sheet 130 can be surface-mounted and fixed to the stress concentration area of ​​the outer beam body with conductive adhesive or epoxy resin to maximize strain transfer efficiency; or, the outer beam piezoelectric sheet 130 can be embedded in the laminated structure of the outer beam body to provide better protection and more stable mechanical coupling.

[0058] The inner beam body 210 is the main structural component of the inner beam assembly 200 in the multi-degree-of-freedom piezoelectric beam device 10. Its main function is to act as a carrier for capturing vibration energy and to provide an attachment substrate for the inner beam piezoelectric sheet 220.

[0059] The inner beam body 210 can be made of a similar elastic material as the outer beam body, but its geometry and dimensions are usually specially designed, for example by adding mass blocks or adjusting the length, width and thickness of the beam, so that its natural frequency matches the main vibration frequency (such as the operating frequency) of the target rotating machinery to achieve a resonance enhancement effect.

[0060] The inner beam body 210 can be designed as a structure nested inside the outer beam body, or coupled to the outer beam body through a flexible connector to form a multi-degree-of-freedom vibration system, thereby generating a large strain at a specific frequency, which is beneficial for efficient energy capture.

[0061] The inner beam piezoelectric element 220 is an energy harvesting element in the inner beam assembly 200 used to convert mechanical vibration energy into electrical energy, and its output electrical signal is the vibration energy.

[0062] The inner beam piezoelectric element 220 can be made of a piezoelectric material with a high electromechanical coupling coefficient, such as high-power PZT ceramic, and is disposed on the inner beam body 210 by means of bonding or encapsulation to maximize energy conversion efficiency.

[0063] The connection method of the inner beam piezoelectric element 220 can be designed as parallel or series to adapt to different voltage or current output requirements, and impedance matching with the subsequent energy management circuit, thereby optimizing energy transmission efficiency.

[0064] This application provides an inner beam piezoelectric element 220 on the inner beam body 210 and configures it to output vibration energy when the inner beam body 210 vibrates with rotating machinery. This enables the inner beam piezoelectric element 220 to efficiently convert the mechanical vibration energy of the inner beam body 210 into electrical energy for system power supply.

[0065] In addition, the inner beam body 210 can be designed to generate large amplitude or large strain at a specific frequency, and then the inner beam piezoelectric sheet 220 can use the large amplitude or large strain to perform efficient energy conversion.

[0066] The inner beam piezoelectric sheet 220 can cover the entire or most of the surface of the inner beam body 210 to make full use of the vibration deformation of the inner beam body 210 and improve the energy trapping area and efficiency; or, in order to further improve the energy trapping efficiency, the inner beam piezoelectric sheet 220 can be designed as a multi-layer stacked structure or adopt a bimorph structure to generate a larger charge output under the same vibration conditions.

[0067] In this application, by directly attaching the outer beam piezoelectric plate 130 to the outer beam, mechanical vibration is efficiently converted into electrical signals when the outer beam vibrates, and vibration signals are output, ensuring the fidelity and reliability of signal acquisition. The inner beam piezoelectric plate 220 is dedicated to converting mechanical energy into electrical energy during vibration, and outputting vibration energy. This allows the outer beam piezoelectric plate 130 and the inner beam piezoelectric plate 220 to perform their respective functions, avoiding mutual interference between signal acquisition and energy capture. This enhances the overall performance and stability of the system, extends the maintenance-free operating time of the system, and significantly improves the efficiency and reliability of the multi-degree-of-freedom piezoelectric beam device 10 in vibration signal acquisition and energy capture, providing a solid foundation for the rotating machinery fault diagnosis system 1.

[0068] In one embodiment, such as Figure 2 As shown, the multi-degree-of-freedom piezoelectric beam device 10 also includes a base 300, and the outer beam body includes a first outer beam body 110 and a second outer beam body 120; wherein, the inner beam body 210 is disposed between the first outer beam body 110 and the second outer beam body 120, and the first outer beam body 110, the second outer beam body 120 and the inner beam body 210 are all mounted on the base 300 to form a plane.

[0069] In this embodiment, the base 300 can be understood as a structural component used to support and fix the multi-degree-of-freedom piezoelectric beam device 10, and the base 300 can provide a stable installation foundation for the entire device.

[0070] As an example, this application can be a rigid plate-like structure made of metal (such as stainless steel or aluminum alloy) or high-strength engineering plastic, fixed to the part of rotating machinery to be tested by means of bolts, welding or bonding.

[0071] As another example, the base 300 can also be a frame structure connected to rotating machinery through multiple support points to distribute stress and enhance overall stability.

[0072] This application provides a base 300 in the multi-degree-of-freedom piezoelectric beam device 10, which can ensure that the multi-degree-of-freedom piezoelectric beam device 10 can maintain its preset geometric position and structural integrity in the high-speed or high-frequency vibration environment of rotating machinery, and prevent displacement, loosening or resonance caused by vibration, thereby providing a stable physical premise for subsequent signal acquisition and energy capture.

[0073] The outer beam body includes a first outer beam body 110 and a second outer beam body 120, which can maintain good dynamic balance and wideband response during vibration signal acquisition.

[0074] Specifically, the first outer beam body 110 and the second outer beam body 120 can be two independent beams, either symmetrical or asymmetrical, which together constitute the support structure of the outer beam assembly 100 and support the outer beam piezoelectric sheet 130. For example, the first outer beam body 110 and the second outer beam body 120 can be two independent cantilever beams, or a single beam with a break in the middle, connected to the base 300 and the inner beam body 210 through a specific connection method. This helps to adjust the natural frequency and vibration mode of the outer beam assembly 100, avoid stress concentration or undesirable vibration coupling that may occur in a single beam, thereby improving the accuracy and reliability of vibration signal acquisition.

[0075] The inner beam body 210 is positioned between the first outer beam body 110 and the second outer beam body 120, which can effectively isolate the inner beam body 210 in the structure, thereby enabling it to focus on capturing vibration energy while reducing direct mechanical coupling interference from the outer beam body.

[0076] For example, the inner beam body 210 can be an independent cantilever beam or simply supported beam, with its two ends or one end surrounded or supported by the structure formed by the first outer beam body 110 and the second outer beam body 120. This allows the inner beam body 210 to respond independently to environmental vibrations and efficiently convert mechanical energy into electrical energy through the inner beam piezoelectric sheet 220. It also helps to precisely tune the vibration characteristics of the inner beam body 210 so that its resonant frequency matches the target energy capture frequency, thereby maximizing the energy capture efficiency.

[0077] The first outer beam body 110, the second outer beam body 120, and the inner beam body 210 are all securely mounted on the base 300. Specifically, they can be connected using various mechanical methods such as bolt fixing, welding, riveting, or high-strength adhesives, thereby avoiding additional friction, collisions, or loosening during vibration. Meanwhile, after the first outer beam body 110, the second outer beam body 120 and the inner beam body 210 are installed on the base 300, they together form a plane, which can ensure that the transmission of vibration energy between the beams is uniform and linear, and avoid energy loss or signal distortion caused by structural twisting, tilting or irregular deformation.

[0078] For example, this application can ensure that the mounting surfaces or vibration planes of all beams are on the same horizontal plane through precise processing technology and assembly tolerance control. This helps to maintain the overall mechanical balance of the multi-degree-of-freedom piezoelectric beam device 10, ensuring that the outer beam assembly 100 can accurately capture the vibration signals of rotating machinery, while the inner beam assembly 200 can efficiently capture energy, thereby improving the performance stability and reliability of the entire system.

[0079] In this application, the base 300 provides solid support for the entire device, ensuring that the outer beam assembly 100 and the inner beam assembly 200 maintain their preset relative positions and geometric configurations during vibration, thereby avoiding signal acquisition distortion caused by structural instability. Simultaneously, the inner beam body 210 is positioned between the first outer beam body 110 and the second outer beam body 120, providing stable support for the inner beam body 210 and allowing it to focus more on capturing vibration energy, reducing external mechanical interference and significantly improving energy capture efficiency. The first outer beam body 110, the second outer beam body 120, and the inner beam body 210 are all firmly mounted on the base 300 and form a plane, ensuring uniform transmission of vibration energy and coordinated operation between components, further improving the fidelity of vibration signal acquisition and the stability of energy conversion, enabling the entire fault diagnosis system to operate stably and reliably for a long time in complex industrial environments.

[0080] In one embodiment, the base 300 is provided with a support portion, a first connecting portion, and a second connecting portion; wherein, one end of the support portion is connected to one end of the first outer beam body 110, the other end of the support portion is connected to one end of the second outer beam body 120, the other end of the first outer beam body 110 is connected to the first connecting portion, and the other end of the second outer beam body 120 is connected to the second connecting portion.

[0081] In this embodiment, one end of the support part is connected to one end of the first outer beam body 110, and the other end of the support part is connected to one end of the second outer beam body 120. This allows the starting ends of the two outer beam bodies to be firmly fixed on the support part of the base 300, ensuring that the base of the outer beam body remains stable when subjected to vibration excitation, thereby avoiding vibration mode distortion caused by base loosening.

[0082] As an example, this application can insert and lock the end of the outer beam body into the mounting part through a precision-machined dovetail groove structure, or bond the end of the outer beam body to the surface of the mounting part with a high-strength adhesive.

[0083] Meanwhile, the other end of the first outer beam body 110 is connected to the first connecting part, and the other end of the second outer beam body 120 is connected to the second connecting part, thereby providing additional fixing points for the far ends of the two outer beam bodies. By fixing at both ends, the overall displacement and torsion of the outer beam bodies can be effectively limited, so that they maintain the expected vibration mode during vibration.

[0084] As an example, this application can fix the end of the outer beam body to the first connection part and the second connection part by bolts.

[0085] As another example, this application can use an elastic clamp to engage the end of the outer beam body into the corresponding connection part, allowing for a certain amount of slight deformation while maintaining overall positional stability.

[0086] In this application, the base 300, by providing a supporting part, a first connecting part, and a second connecting part, secures the starting ends of the first outer beam body 110 and the second outer beam body 120, effectively suppressing vibration and displacement of the beam base. Simultaneously, the first and second connecting parts provide support to the other end of the outer beam body, further enhancing the overall rigidity and stability of the outer beam body and improving the structural stability of the outer beam assembly 100 under rotating machinery vibration environments. This effectively avoids vibration signal distortion or resonance interference caused by unstable connections, thereby ensuring the accuracy of vibration signal acquisition. Furthermore, it also helps the inner beam assembly 200 to efficiently capture energy on a stable base, reducing energy loss, improving energy capture efficiency, and ensuring the system's sensing and energy capture performance.

[0087] In one embodiment, a plurality of inner beam assemblies 200 are provided between the first outer beam body 110 and the second outer beam body 120, and the plurality of inner beam assemblies 200 are arranged in an array.

[0088] Specifically, this application can provide multiple inner beam assemblies 200 between the first outer beam body 110 and the second outer beam body 120. Each inner beam body 210 is equipped with an inner beam piezoelectric sheet 220, and the inner beam bodies 210 are arranged in an array between the first outer beam body 110 and the second outer beam body 120. This overcomes the problem of insufficient performance of a single beam, and by superimposing the performance of multiple beams, the overall performance can be improved. This allows for maintaining high energy capture efficiency over a wider frequency range, adapting to variable frequency vibrations caused by fluctuations in the rotational speed of rotating machinery. Simultaneously, it can multiply the output power, meeting the power supply requirements of loads such as microcontrollers, and ensuring the stability and reliability of the output. Furthermore, the inner beam bodies 210 are arranged in an array between the first outer beam body 110 and the second outer beam body 120, and each inner beam body 210 can also have its bandwidth and energy capture performance specifically adjusted to achieve the superposition of overall performance.

[0089] In one embodiment, such as Figure 2 As shown, the outer beam assembly 100 also includes an outer beam magnet 140, and the inner beam assembly 200 also includes an inner beam magnet 230. The base 300 is provided with a first magnet 301 and a second magnet 302. One end of the outer beam magnet 140 is connected to one end of the first outer beam body 110, and the other end of the outer beam magnet 140 is connected to the other end of the second outer beam body 120. The inner beam magnet 230 is mounted on the inner beam body 210. The outer beam magnet 140 is located between the first magnet 301 and the inner beam magnet 230, and the inner beam magnet 230 is located between the outer beam magnet 140 and the second magnet 302. The near ends of two adjacent magnets are both magnetic poles of the same name, so as to form a magnetic repulsion force between the magnets.

[0090] In this embodiment, the outer beam magnet 140 can be understood as a magnetic element disposed on the outer beam assembly 100. The outer beam magnet 140 can enhance the vibration response of the outer beam body through magnetic coupling.

[0091] The outer beam magnet 140 can be a permanent magnet, such as a neodymium iron boron magnet or a ferrite magnet. Its shape can be designed according to the structure of the outer beam body and the required magnetic coupling strength, so as to effectively expand the effective vibration range of the outer beam and improve its ability to capture broadband vibration signals.

[0092] The inner beam magnet 230 can be understood as a magnetic element disposed on the inner beam assembly 200. The inner beam magnet 230 can enhance the vibration amplitude of the inner beam body 210 through magnetic coupling, thereby increasing the strain of the piezoelectric material and thus improving the energy capture efficiency.

[0093] The inner beam magnet 230 can also be a permanent magnet, and its size and shape can be designed according to the structure of the inner beam body 210 and the required magnetic coupling strength.

[0094] The first magnet 301 and the second magnet 302 can be understood as magnetic elements fixedly mounted on the base 300. The first magnet 301 and the second magnet 302 serve as external magnetic field sources and form magnetic coupling with the outer beam magnet 140 and the inner beam magnet 230.

[0095] The first magnet 301 and the second magnet 302 may also be permanent magnets, such as fixed magnetic blocks mounted on the base 300, whose position and polarity are precisely designed to generate the desired interaction force with the moving beam magnet.

[0096] Specifically, one end of the outer beam magnet 140 is connected to one end of the first outer beam body 110, and the other end of the outer beam magnet 140 is connected to the other end of the second outer beam body 120, ensuring that the outer beam magnet 140 and the outer beam body vibrate as a whole, so that the magnetic coupling can effectively act on the overall movement of the outer beam, thereby enhancing its response to vibration signals.

[0097] The inner beam magnet 230 is installed on the inner beam body 210, so that the inner beam magnet 230 can vibrate synchronously with the inner beam body 210, thereby generating displacement in the magnetic field, realizing effective magnetic coupling, and thus improving the energy capture efficiency of the inner beam.

[0098] The outer beam magnet 140 is located between the first magnet 301 and the inner beam magnet 230, and the inner beam magnet 230 is located between the outer beam magnet 140 and the second magnet 302, thereby forming a magnetic chain that enables continuous magnetic interaction between the magnets. This provides continuous magnetic coupling during the vibration of the entire multi-degree-of-freedom piezoelectric beam device 10, which helps to broaden the resonant frequency band of the system.

[0099] For example, the N pole of the first magnet 301 is close to the N pole of the outer beam magnet 140, the S pole of the outer beam magnet 140 is close to the S pole of the inner beam magnet 230, and the N pole of the inner beam magnet 230 is close to the N pole of the second magnet 302. That is, the same magnetic poles of adjacent magnets are close to each other, which will generate magnetic repulsion. The magnetic repulsion can be used as a nonlinear elastic force, which is superimposed on the mechanical elastic force of the piezoelectric beam, thereby changing the equivalent stiffness of the system and introducing nonlinear vibration characteristics. This helps to broaden the effective operating frequency band of the system and may amplify the vibration amplitude at a specific frequency.

[0100] In this application, by introducing an outer beam magnet 140, an inner beam magnet 230, a first magnet 301, and a second magnet 302, the problem of narrow vibration response bandwidth of the multi-degree-of-freedom piezoelectric beam device 10 is effectively solved. Furthermore, during mechanical vibration, an additional nonlinear force is applied to the piezoelectric beam through magnetic repulsion, thereby altering the system's inherent frequency characteristics and enabling it to produce a significant vibration response over a wider frequency range. The magnetic interaction between the outer beam magnet 140 and the first magnet 301 and inner beam magnet 230 enhances the vibration amplitude of the outer beam body, allowing the outer beam piezoelectric element 130 to output high-fidelity vibration signals over a wider frequency range. This improves the accuracy of signal acquisition and provides a more reliable data foundation for subsequent fault diagnosis.

[0101] Meanwhile, the magnetic force between the inner beam magnet 230, the outer beam magnet 140, and the second magnet 302 significantly increases the vibration strain of the inner beam body 210, enabling the inner beam piezoelectric sheet 220 to efficiently convert mechanical vibration energy into electrical energy over a wider frequency range. This improves energy capture efficiency, ensures a continuous and stable power supply for the microcontroller 20, and enhances the reliability of the system's self-powered supply. Consequently, the multi-degree-of-freedom piezoelectric beam device 10 can adapt to the variable frequency vibration generated by rotating machinery under different operating conditions, effectively broadening the system's operating frequency band. This improves the accuracy of rotating machinery fault diagnosis and the stability of the system's self-powered supply without sacrificing signal integrity and energy capture efficiency.

[0102] In one embodiment, such as Figure 3 and Figure 4 As shown, the system also includes a signal conditioning and sampling circuit 30; wherein, the two ends of the signal conditioning and sampling circuit 30 are respectively connected to the outer beam assembly 100 and the microcontroller 20, and are configured to process the vibration signal output by the outer beam assembly 100 to output a digital signal to the microcontroller 20; the microcontroller 20 is configured to perform fault diagnosis on the rotating machinery based on the digital signal to obtain the fault analysis results of the rotating machinery.

[0103] In this embodiment, the signal conditioning and sampling circuit 30 can preprocess the vibration signal output from the outer beam assembly 100 to facilitate digital acquisition and subsequent processing by the microcontroller 20. The signal conditioning and sampling circuit 30 can optimize signal quality, ensure signal integrity and accuracy, thereby providing a high-quality data foundation for subsequent fault diagnosis.

[0104] Specifically, the signal conditioning and sampling circuit 30 is connected to the outer beam assembly 100 and the microcontroller 20. It is configured to process vibration signals and output digital signals, thereby conditioning the original vibration signals output by the outer beam assembly 100, avoiding signal distortion and noise interference during transmission, and providing high-quality input to the microcontroller 20 to improve the accuracy of fault diagnosis.

[0105] In one embodiment, such as Figure 3 and Figure 4 As shown, the system also includes an energy management and storage circuit 40; wherein, the two ends of the energy management and storage circuit 40 are respectively connected to the inner beam assembly 200 and the microcontroller 20, and are configured to convert the vibration energy output by the inner beam assembly 200 into power supply for the microcontroller 20.

[0106] In this embodiment, the energy management and storage circuit 40 can convert, store and manage the vibration energy captured by the inner beam assembly 200 to provide a stable and reliable power supply to the microcontroller 20, ensuring that the microcontroller 20 can work continuously and stably in a vibration environment.

[0107] Specifically, the energy management and storage circuit 40 is connected to the inner beam assembly 200 and the microcontroller 20. It is configured to convert vibration energy into power supply, thereby managing the vibration energy output by the inner beam assembly 200. This solves the fluctuation problem when energy is directly supplied, ensures that the microcontroller 20 receives a stable power supply, and supports the continuous operation of the system in a vibration environment.

[0108] In one embodiment, such as Figure 3 and Figure 4As shown, the signal conditioning and sampling circuit 30 includes a high input impedance buffer unit 310, an analog filter unit 320, and a bias / limiting protection unit 330. The two ends of the high input impedance buffer unit 310 are connected to the outer beam assembly 100 and one end of the analog filter unit 320, respectively. The two ends of the bias / limiting protection unit 330 are connected to the other end of the analog filter unit 320 and the microcontroller 20, respectively. The high input impedance buffer unit 310 is configured to perform impedance transformation and isolation buffering on the vibration signal to obtain a vibration signal after impedance transformation and isolation buffering. The analog filter unit 320 is configured to filter the vibration signal after impedance transformation and isolation buffering to obtain a filtered vibration signal. The bias / limiting protection unit 330 is configured to perform DC bias adjustment and amplitude limiting on the filtered vibration signal to obtain a vibration signal after DC bias adjustment and amplitude limiting. The microcontroller 20 is configured to perform fault diagnosis on the rotating machinery based on the vibration signal after DC bias adjustment and amplitude limiting to obtain the fault analysis results of the rotating machinery.

[0109] In this embodiment, the high input impedance buffer unit 310 can reduce the load effect on the output signal of the outer beam assembly 100, and avoid signal distortion or attenuation due to impedance mismatch during transmission, thereby improving the fidelity of signal acquisition.

[0110] As an example, the high input impedance buffer unit 310 can be configured as a voltage follower circuit using a field-effect transistor (FET) input operational amplifier (Op-Amp) with an input impedance in the megaohm range, effectively isolating the output of the piezoelectric sensor from the load of subsequent circuitry.

[0111] As another example, the high input impedance buffer unit 310 can be an instrumentation amplifier with extremely high input impedance and common-mode rejection ratio, which can amplify and buffer weak vibration signals with high fidelity.

[0112] The analog filter unit 320 can remove high-frequency noise and power frequency interference from the signal, while preventing aliasing during the digitization process.

[0113] As an example, the analog filter unit 320 can be implemented using an active low-pass filter of the type Butterworth or Chebyshev, which can effectively filter out noise outside the target frequency band by selecting an appropriate cutoff frequency and order.

[0114] As another example, the analog filter unit 320 can also be a combination of an RC passive filter and an active filter, which simplifies the circuit design while ensuring the filtering effect.

[0115] The bias / limiting protection unit 330 can adjust the filtered AC vibration signal to the input range of the analog-to-digital converter (ADC) of the microcontroller 20, preventing the signal from being too large and damaging the ADC or too small and causing insufficient resolution.

[0116] Specifically, after receiving the pre-processed analog signal, the microcontroller 20 converts it into a digital signal using its internal ADC. Then, it uses its built-in processor to execute a preset fault diagnosis algorithm, such as feature extraction and pattern recognition based on time-domain, frequency-domain analysis or machine learning models (such as lightweight convolutional neural networks), and finally outputs analysis results such as fault type and severity.

[0117] In this application, in the signal conditioning and sampling circuit 30, the high input impedance buffer unit 310 performs impedance transformation and isolation buffering on the vibration signal, which significantly reduces the load effect on the output signal of the outer beam assembly 100 and avoids signal distortion during transmission, thereby greatly improving the fidelity of vibration signal acquisition. The analog filtering unit 320 performs precise filtering on the vibration signal after impedance transformation and isolation buffering, effectively removing high-frequency noise and potential aliasing interference, ensuring the purity of the signal. The bias / limiting protection unit 330 performs DC bias adjustment and amplitude limiting on the filtered vibration signal, so that the signal can accurately match the input range of the analog-to-digital converter (ADC) of the microcontroller 20, preventing diagnostic errors caused by signal overload or offset, providing high-quality and reliable input for subsequent fault diagnosis, and thus the microcontroller 20 performs fault diagnosis, significantly improving the accuracy of fault analysis results.

[0118] In one embodiment, such as Figure 3 and Figure 4 As shown, the energy management and storage circuit 40 includes a rectifier unit 410, an energy / charging management unit 420, an energy storage unit 430, and a buck-boost unit 440. One end of the rectifier unit 410 is connected to the inner beam assembly 200, the other end of the rectifier unit 410 is connected to the first end of the energy / charging management unit 420, the second end of the energy / charging management unit 420 is connected to one end of the energy storage unit 430, the other end of the energy storage unit 430 is connected to one end of the buck-boost unit 440, and the other end of the buck-boost unit 440 is connected to the microcontroller 20. The rectifier unit 410 is configured to convert the vibration energy output by the inner beam assembly 200 into DC power. The energy / charging management unit 420 is configured to manage the charging of the energy storage unit 430 based on the DC power. The energy storage unit 430 is configured to output peak power. The buck-boost unit 440 is configured to output power to the microcontroller 20 based on the peak power.

[0119] In this embodiment, the inner beam assembly 200 outputs AC power, which is converted into stable DC power by the rectifier unit 410 for subsequent energy management and storage. The rectifier unit 410 can be implemented using a full-wave bridge rectifier circuit, such as a bridge rectifier composed of four diodes, to convert AC voltage into pulsating DC voltage.

[0120] In addition, to improve efficiency, the rectifier unit 410 can also use a synchronous rectifier, which replaces the traditional diode by controlling the switching of the MOSFET, thereby reducing conduction losses.

[0121] The energy / charging management unit 420 ensures the safe and efficient charging of the energy storage unit 430 and provides overcharge and over-discharge protection. The energy / charging management unit 420 can employ a dedicated power management integrated circuit (PMIC), such as a charging management chip with maximum power point tracking (MPPT) functionality, which can dynamically adjust the charging strategy based on input voltage and current to maximize energy harvesting efficiency.

[0122] The energy storage unit 430 can be configured to output the peak power of the microcontroller 20 to provide power to the microcontroller 20. In energy harvesting systems, environmental vibration energy is often intermittent or fluctuating. The energy storage unit 430 is used to smooth out such energy fluctuations and provide a stable energy output when the microcontroller 20 requires higher instantaneous power (e.g., for data acquisition, computation, or wireless communication). The energy storage unit 430 can be implemented using a rechargeable battery (such as a lithium-ion battery or a nickel-metal hydride battery) or a supercapacitor.

[0123] The buck-boost unit 440 can adjust the voltage output from the energy storage unit 430 to the stable operating voltage required by the microcontroller 20 and its peripherals. Since the voltage of the energy storage unit 430 may vary with its state of charge, the buck-boost unit 440 can boost or buck the voltage, ensuring that the microcontroller 20 always operates at its rated voltage. The buck-boost unit 440 can employ a switch-mode power supply (SMPS), such as a buck converter, boost converter, or buck-boost converter, to achieve efficient voltage conversion. For example, a buck converter is used when the voltage of the energy storage unit 430 is higher than the voltage required by the microcontroller 20; a boost converter is used when the voltage is lower than the required voltage.

[0124] In this application, the rectifier unit 410 efficiently converts the vibration energy output by the inner beam assembly 200 into a stable DC power supply, maximizing energy conversion efficiency and reducing energy loss. The energy / charging management unit 420 performs intelligent charging management of the energy storage unit 430 based on this DC power supply, optimizing the charging process and improving the efficiency and safety of energy storage. The energy storage unit 430 is configured to output the peak power of the microcontroller 20 when needed, providing a stable and reliable power supply for the microcontroller 20, ensuring the continuous and stable operation of the system under environmental vibration fluctuations or instantaneous high power consumption demands. The buck-boost unit 440 can dynamically adjust the output voltage according to the voltage changes of the energy storage unit 430 to adapt to the working requirements of the microcontroller 20, maintain the stability of the power supply, and achieve high efficiency in energy capture, enabling the entire rotating machinery fault diagnosis system 1 to achieve long-term, maintenance-free self-powered operation.

[0125] In one embodiment, such as Figure 3 and Figure 4 As shown, the energy management and storage circuit 40 also includes a power gating unit; one end of the power gating unit is connected to the third terminal of the energy / charging management unit 420, and the other end of the power gating unit is connected to the microcontroller 20; the power gating unit is configured to control the energy / charging management unit 420 based on the control signal output by the microcontroller 20, so as to control the working state of the rotating machinery fault diagnosis system 1.

[0126] In this embodiment, the power gating unit is connected to the third terminal of the energy / charging management unit 420. The power gating unit can receive status information (e.g., battery charging status, voltage threshold trigger signal) from the energy / charging management unit 420 or send control commands (e.g., request to stop charging, enable a specific power output mode) to it.

[0127] The power gating unit can operate the energy / charging management unit 420 according to the control signals output by the microcontroller 20. When the microcontroller 20 determines that the system needs to enter a low-power mode, wake up, or adjust the charging strategy, the microcontroller 20 sends a corresponding control signal. After receiving the control signal, the power gating unit will adjust the working state of the rotating machinery fault diagnosis system 1 accordingly.

[0128] The working states of the rotating machinery fault diagnosis system 1 may include, but are not limited to: fully active state (data acquisition, processing and transmission), hibernation state (maintaining only basic functions and waiting to be woken up), deep sleep state (most modules are powered off and power consumption is extremely low), and charging state (focusing on energy harvesting and storage).

[0129] In this application, by introducing a power gating unit and having it controlled by a microcontroller 20 to regulate the energy / charging management unit 420, dynamic and intelligent management of the operating status of the rotating machinery fault diagnosis system 1 is achieved. When the system has sufficient energy, the microcontroller 20 can instruct the power gating unit to maintain the normal power supply to the energy / charging management unit 420, ensuring the continuous operation of the system for diagnostic tasks. When the energy is insufficient, the microcontroller 20 can promptly issue a control signal to cut off or adjust the power supply output of the energy / charging management unit 420 through the power gating unit, causing the system to enter a sleep or low-power mode. This effectively avoids the problem of system crashes under low voltage or the inability to recover due to energy depletion, significantly improving the system's energy utilization efficiency and operational stability, ensuring long-term self-powering capability under limited energy supply, thereby reducing maintenance costs and improving system reliability.

[0130] In one embodiment, such as Figure 5 As shown, this application also provides a method for diagnosing rotating machinery faults, which is applied in the rotating machinery fault diagnosis system 1 provided in this application, such as... Figure 5 As shown, the method includes steps S510, S520 and S530.

[0131] S510. With the inner beam assembly 200 used to power the microcontroller 20, the vibration signal is preprocessed to obtain the preprocessed vibration signal. S520. Input the preprocessed vibration signal into the preset diagnostic identification model to obtain the fault analysis results of the rotating machinery. S530: Send the fault analysis results to the terminal device and display them visually.

[0132] Specifically, this application captures the vibration energy of rotating machinery through the inner beam assembly 200 in the multi-degree-of-freedom piezoelectric beam device 10, and converts it into electrical energy through the energy management and storage circuit 40 to provide continuous power to the microcontroller 20. When the power supply reaches a preset stable operating state, the microcontroller 20 is activated and begins to receive vibration signals from the outer beam assembly 100.

[0133] This application performs signal preprocessing on vibration signals to eliminate noise, correct biases, or adjust signal characteristics, making them more suitable for subsequent diagnostic and identification model analysis. For example, the acquired vibration signals can be standardized by subtracting the mean and dividing by the standard deviation to adjust the signal amplitude and distribution, thereby reducing the impact of signal amplitude fluctuations under different operating conditions on the diagnostic results.

[0134] In addition, this application can also perform filtering processing, such as using a bandpass filter to remove high-frequency noise and low-frequency drift in the signal to highlight the characteristic frequency components related to the fault.

[0135] Meanwhile, this application can set a diagnostic identification model in the microcontroller 20. The diagnostic identification model can be pre-trained and deployed on the microcontroller 20. At the same time, the diagnostic identification model can extract features from complex vibration data and compare them with known fault modes, thereby determining the current health status of the rotating machinery or identifying potential fault types.

[0136] Specifically, the diagnostic identification model can be a lightweight machine learning model, such as a one-dimensional convolutional neural network (1D-CNN), support vector machine (SVM), or decision tree model. It can be trained offline using a large amount of historical vibration data (including data under normal operation and various fault conditions) to learn feature representations of different fault modes. After training, the parameters of the diagnostic identification model are fixed and loaded into the microcontroller 20, enabling it to run efficiently on resource-constrained edge devices.

[0137] Alternatively, the diagnostic identification model can also be a rule-based reasoning system built on expert knowledge, which diagnoses faults through a series of logical judgments and threshold comparisons. For example, when the amplitude of a specific frequency component in the preprocessed signal exceeds a preset threshold, the system will determine that a certain type of fault exists.

[0138] After inputting the pre-processed vibration signal into a preset diagnostic identification model to obtain the fault analysis results of the rotating machinery, the fault analysis results can be sent to the terminal device and displayed visually so that operators or maintenance personnel can understand the equipment status in a timely manner and take corresponding measures.

[0139] Fault analysis results can include information such as fault type (e.g., bearing inner ring fault, outer ring fault, rolling element fault), fault severity, and confidence level.

[0140] As an example, this application can transmit the results to terminal devices such as smartphones, tablets, gateways, or host computers via a wireless communication module (e.g., Bluetooth Low Energy (BLE), Wi-Fi, or LoRa). After receiving the data, the terminal device parses the data through the corresponding application or software and displays it visually in the form of charts, text reports, or status indicators, such as displaying fault trend graphs, fault type lists, or device health scores.

[0141] As one example, if the system integrates a local display unit (such as a small OLED screen or LED indicator), it can directly display brief fault information or status indications on the device, such as indicating that the device is in a normal, warning, or alarm state through LEDs of different colors.

[0142] In this application, vibration signal preprocessing is initiated only when the inner beam assembly 200 is used to power the microcontroller 20. This ensures that the diagnostic operation is performed under stable energy supply conditions, effectively avoiding diagnostic interruptions or data processing errors caused by energy fluctuations, thereby guaranteeing the reliability and continuity of the diagnostic process. Simultaneously, by preprocessing the vibration signal, such as standardization or filtering, noise interference can be effectively eliminated and signal deviations corrected, resulting in higher quality data input to the diagnostic identification model and significantly improving the accuracy and robustness of fault diagnosis. The preprocessed signal is then directly input into the diagnostic identification model pre-installed in the microcontroller 20 for local inference, realizing… Edge computing significantly reduces the amount of raw data that needs to be transmitted, requiring only the transmission of concise fault analysis results. This not only drastically reduces communication bandwidth requirements and energy consumption, extending the system's lifespan, but also avoids data transmission delays and packet loss in network congestion or bandwidth-limited environments. By sending fault analysis results to terminal devices and displaying them visually, users can intuitively and promptly obtain device health information, facilitating rapid response and maintenance decisions. At the same time, it maintains the low-power, maintenance-free operation of the entire system. While ensuring high-fidelity signal acquisition and efficient energy capture, it further optimizes the diagnostic process, achieving intelligent fault diagnosis with self-powered operation and low bandwidth usage.

[0143] In one embodiment, the method further includes: when the energy management storage circuit 40 converts the vibration energy output by the inner beam assembly 200 into power for the microcontroller 20, when the power supply voltage of the energy management storage circuit 40 reaches a preset start-up threshold, starting the microcontroller 20; when the power supply voltage drops to a preset cut-off threshold, controlling the energy management storage circuit 40 to stop supplying power to the microcontroller 20, so that the microcontroller 20 enters a sleep state.

[0144] In this embodiment, the energy management and storage circuit 40 is responsible for rectifying, storing, stabilizing or boosting / boosting the vibration energy output by the inner beam assembly 200, and ultimately providing a stable power supply to the microcontroller 20.

[0145] The startup threshold can be understood as a preset voltage value, such as 3.8V. When the energy management storage circuit 40 detects that its output supply voltage reaches or exceeds this preset startup threshold, it indicates that the energy storage unit 430 has accumulated enough energy to support the normal startup and operation of the microcontroller 20 and its related peripherals. At this time, the microcontroller 20 starts up and switches from the power-off or deep sleep state to the normal working state.

[0146] The cutoff threshold can be understood as a preset voltage value, such as 3.0V, which is usually lower than the start-up threshold. When the energy management storage circuit 40 detects that the supply voltage has dropped to this preset cutoff threshold, it indicates that the energy of the energy storage unit 430 is insufficient to maintain the stable operation of the microcontroller 20, and measures need to be taken to protect the system. At this time, the energy management storage circuit 40 will control the shutdown of power supply to the microcontroller 20.

[0147] In this application, an intelligent energy management strategy is introduced into the rotating machinery fault diagnosis system 1. When the supply voltage of the energy management storage circuit 40 reaches a preset start-up threshold, the system starts the microcontroller 20, ensuring that the microcontroller 20 only starts working under conditions of sufficient and stable energy. This effectively avoids problems such as diagnostic operation failure and microcontroller 20 malfunction due to insufficient voltage, significantly improving the accuracy of diagnosis and the reliability of system operation. Simultaneously, when the supply voltage drops to a preset cutoff threshold, the energy management storage circuit 40 stops supplying power to the microcontroller 20 and causes the microcontroller 20 to enter a sleep state. This promptly prevents the system from continuing to operate when energy is insufficient, avoiding ineffective energy consumption and protecting the energy storage unit 430 from over-discharge damage, thereby extending the service life of the entire system. This allows the rotating machinery fault diagnosis system 1 to better cope with the instability of environmental vibration energy harvesting, achieving system-level energy efficiency optimization and providing a solid guarantee for long-term, maintenance-free self-powered operation, greatly improving the system's engineering deployability.

[0148] In one embodiment, such as Figure 6 As shown, the methods for diagnosing rotating machinery faults include: Energy storage and cold start: The system is initially in the start / sleep state. The piezoelectric sheet of the inner beam generates electricity under vibration excitation and charges the energy storage unit. When the energy storage voltage is greater than or equal to the start threshold Vstart, the energy management / charging management unit enables power gating, and the microcontroller powers on and enters the working state. If the energy storage voltage is less than the start threshold Vstart, charging continues. External beam signal acquisition: After the microcontroller is powered on and stabilized, the output signal of the piezoelectric sheet of the external beam is acquired by ADC sampling to form a window of data with a length of N points (e.g., N=1024). Signal preprocessing: Perform preprocessing such as standardization / normalization on the window data to reduce the impact of amplitude fluctuations and changes in operating conditions on the recognition results; Edge reasoning and fault identification: The preprocessed data is input into the diagnostic identification model for reasoning, and the fault category and confidence level are output. The diagnostic identification model is preferably a lightweight sequence classification model suitable for embedded deployment, and can be quantized to reduce computing power and storage overhead. Results output: The analysis results are output to the local OLED display or sent to the terminal processor via BLE wireless for low-bandwidth result reporting; After reporting low-bandwidth results, if the energy storage voltage is greater than or equal to the operating voltage Vwork, the diagnostic frequency is increased or the composite window is increased; if the energy storage voltage is less than the operating voltage Vwork, the frequency is reduced or transmission is paused or low-power mode is entered; if the energy storage voltage is less than or equal to the cutoff threshold Vstop, the power supply is cut off and the system enters sleep mode.

[0149] In addition, after completing a diagnosis, this application can read the energy storage voltage and perform energy sensing scheduling. When the voltage is higher than the working threshold, the sampling / inference frequency can be increased or a second sampling confirmation can be performed. When the voltage is insufficient, the sampling rate can be reduced or wireless transmission can be paused and the device can enter deep sleep, waiting for the next round of charging before performing the diagnosis again.

[0150] The rotating machinery fault diagnosis system and method provided in this application have the following technical advantages: 1. By using a nested multi-degree-of-freedom structure of "outer beam sensing + inner beam energy harvesting", the physical separation of sensing and power generation is achieved, reducing the interference of the energy extraction circuit on high-frequency fault signals; 2. By using electrical isolation and a high input impedance sampling channel, the fidelity of vibration signal acquisition is improved while ensuring energy capture efficiency; 3. By using edge inference, the original waveform is converted into a small number of status codes, achieving low-bandwidth transmission and reducing communication power consumption; 4. Achieve long-term self-powered operation and maintenance-free operation through energy sensing and scheduling strategies, thereby improving the deployability of the project.

[0151] Meanwhile, the rotating machinery fault diagnosis system and method provided in this application can be used for online condition monitoring and bearing fault diagnosis of rotating machinery, and can be applied to bearing / rotor systems of motors, fans, compressors, reducers, machine tool spindles, etc.

[0152] In application, the multi-degree-of-freedom piezoelectric beam device can be installed on the bearing seat, housing, or support structure surface by bolts / adhesive; the inner beam captures energy under the vibration of the equipment during operation and supplies power to the nodes; the outer beam outputs vibration signals, which are used to infer the fault category and confidence level through the diagnostic identification model, and are periodically reported to the mobile phone / gateway / host computer via BLE / other wireless methods, realizing long-term online monitoring without wiring or battery replacement.

[0153] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A rotating machinery fault diagnostic system characterized by, include: microcontroller; A multi-degree-of-freedom piezoelectric beam device is installed on rotating machinery; the multi-degree-of-freedom piezoelectric beam device includes an outer beam assembly and at least one inner beam assembly, the outer beam assembly and the inner beam assembly are respectively connected to the microcontroller; The outer beam assembly is configured to collect vibration signals from the rotating machinery. The inner beam assembly is configured to capture the vibrational energy of the rotating machinery to power the microcontroller; The microcontroller is configured to perform fault diagnosis on the rotating machinery based on the vibration signal, so as to obtain the fault analysis results of the rotating machinery.

2. The rotating machinery fault diagnosis system according to claim 1, characterized in that, The outer beam assembly includes an outer beam body and an outer beam piezoelectric sheet, and the inner beam assembly includes an inner beam body and an inner beam piezoelectric sheet. The piezoelectric sheet of the outer beam is disposed on the outer beam body and is configured to output the vibration signal when the outer beam body vibrates with the rotating machinery. The piezoelectric element of the inner beam is disposed on the inner beam body and is configured to output the vibration energy when the inner beam body vibrates with the rotating machinery.

3. The rotating machinery fault diagnosis system according to claim 2, characterized in that, The multi-degree-of-freedom piezoelectric beam device also includes a base, and the outer beam body includes a first outer beam body and a second outer beam body; The inner beam body is located between the first outer beam body and the second outer beam body. The first outer beam body, the second outer beam body, and the inner beam body are all mounted on the base to form a plane.

4. The rotating machinery fault diagnosis system according to claim 3, characterized in that, The base is provided with a support part, a first connecting part, and a second connecting part; Wherein, one end of the supporting part is connected to one end of the first outer beam body, the other end of the supporting part is connected to one end of the second outer beam body, the other end of the first outer beam body is connected to the first connecting part, and the other end of the second outer beam body is connected to the second connecting part; or / and A plurality of inner beam assemblies are provided between the first outer beam body and the second outer beam body, and the plurality of inner beam assemblies are arranged in an array.

5. The rotating machinery fault diagnosis system according to claim 3, characterized in that, The outer beam assembly also includes an outer beam magnet, the inner beam assembly also includes an inner beam magnet, and the base is provided with a first magnet and a second magnet; Wherein, one end of the outer beam magnet is connected to one end of the first outer beam body, the other end of the outer beam magnet is connected to the other end of the second outer beam body, and the inner beam magnet is installed on the inner beam body; The outer beam magnet is disposed between the first magnet and the inner beam magnet, and the inner beam magnet is disposed between the outer beam magnet and the second magnet; The near ends of two adjacent magnets are both magnetic poles of the same name, so as to create a magnetic repulsion between the magnets.

6. The rotating machinery fault diagnosis system according to any one of claims 1-5, characterized in that, The system also includes signal conditioning and sampling circuitry; The signal conditioning and sampling circuit is connected at both ends to the outer beam assembly and the microcontroller, respectively, and is configured to process the vibration signal output by the outer beam assembly to output a digital signal to the microcontroller; the microcontroller is configured to perform fault diagnosis on the rotating machinery based on the digital signal to obtain the fault analysis results of the rotating machinery; or / and, The system also includes an energy management and storage circuit; The energy management and storage circuit is connected at both ends to the inner beam assembly and the microcontroller, respectively, and is configured to convert the vibration energy output by the inner beam assembly into power supply for the microcontroller.

7. The rotating machinery fault diagnosis system according to claim 6, characterized in that, The signal conditioning and sampling circuit includes a high input impedance buffer unit, an analog filtering unit, and a bias / limiting protection unit. The high input impedance buffer unit is connected to one end of the outer beam assembly and one end of the analog filter unit, respectively, and the bias / limiting protection unit is connected to the other end of the analog filter unit and the microcontroller, respectively. The high input impedance buffer unit is configured to perform impedance transformation and isolation buffering on the vibration signal to obtain the vibration signal after impedance transformation and isolation buffering. The analog filtering unit is configured to filter the vibration signal after impedance transformation and isolation buffering to obtain the filtered vibration signal. The bias / limiting protection unit is configured to perform DC bias adjustment and amplitude limiting on the filtered vibration signal to obtain a vibration signal after DC bias adjustment and amplitude limiting. The microcontroller is configured to perform fault diagnosis on the rotating machinery based on the vibration signal after DC bias adjustment and amplitude limiting, so as to obtain the fault analysis results of the rotating machinery; or / and, The energy management and storage circuit includes a rectifier unit, an energy / charging management unit, an energy storage unit, and a buck-boost unit; Wherein, one end of the rectifier unit is connected to the inner beam assembly, the other end of the rectifier unit is connected to the first end of the energy / charging management unit, the second end of the energy / charging management unit is connected to one end of the energy storage unit, the other end of the energy storage unit is connected to one end of the buck-boost unit, and the other end of the buck-boost unit is connected to the microcontroller; The rectifier unit is configured to convert the vibration energy output by the inner beam assembly into DC power. The energy / charging management unit is configured to manage the charging of the energy storage unit based on the DC power supply. The energy storage unit is configured to output peak power; the buck-boost unit is configured to output power to the microcontroller based on the peak power.

8. The rotating machinery fault diagnosis system according to claim 7, characterized in that, The energy management and storage circuit also includes a power gating unit; Wherein, one end of the power gating unit is connected to the third end of the energy / charging management unit, and the other end of the power gating unit is connected to the microcontroller; The power gating unit is configured to control the energy / charging management unit based on the control signal output by the microcontroller, so as to control the working state of the rotating machinery fault diagnosis system.

9. A method for diagnosing faults in rotating machinery, characterized in that, The method, applied to the rotating machinery fault diagnosis system according to any one of claims 1-8, comprises: With the inner beam assembly used to power the microcontroller, the vibration signal is preprocessed to obtain a preprocessed vibration signal. The preprocessed vibration signal is input into a preset diagnostic identification model to obtain the fault analysis results of the rotating machinery; The fault analysis results are sent to the terminal device and displayed visually.

10. The method for diagnosing rotating machinery faults according to claim 9, characterized in that, The method further includes: When the energy management and storage circuit converts the vibration energy output by the inner beam assembly into power for the microcontroller, the microcontroller is activated when the power supply voltage of the energy management and storage circuit reaches a preset start-up threshold. When the supply voltage drops to a preset cutoff threshold, the energy management storage circuit is controlled to stop supplying power to the microcontroller, so that the microcontroller enters a sleep state.

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