Vibration self-powered acoustic emission wireless monitoring device and system

Abstract

The application discloses a vibration self-powered acoustic emission wireless monitoring device and system, and relates to the technical field of self-power supply.The application comprises a data collection module, a self-power supply module, an acoustic emission monitoring module and a wireless communication module.The data collection module is used for collecting efficiency data of different power supply modes of the device self-power supply in historical records and vibration data when the device generates an anomaly.The self-power supply module is used for storing electrical energy converted from mechanical energy of vibration by using different power supply modes, and self-power supply is realized by using the stored electrical energy when the system works.The acoustic emission monitoring module is used for collecting acoustic emission signals generated in the working of the device by using a piezoelectric ceramic sensor, judging whether the device has an abnormal risk and giving a warning.The wireless communication module is used for sending an abnormal warning signal to a client of a user by using a wireless network when the system judges that the device has an abnormal risk and gives a warning, so as to remind the user to maintain the device in the abnormal risk.

Description

Technical Field

[0001] This invention relates to the field of self-powered technology, specifically to a vibration self-powered acoustic emission wireless monitoring device and system. Background Technology

[0002] In many industrial and engineering applications, long-term monitoring of equipment or structures is required. Traditional wired monitoring methods suffer from problems such as complex wiring, high costs, and difficult maintenance, limiting the widespread application of monitoring systems. Wireless monitoring technology, on the other hand, offers advantages such as no wiring required, easy installation, and high flexibility, making it a development trend in the monitoring field. However, the power supply issue for wireless monitoring equipment has always been a key factor restricting its development. Traditional battery-powered methods require regular battery replacements, increasing maintenance costs and potentially causing monitoring interruptions. Vibration is a widespread phenomenon in nature and engineering, and many devices generate vibration during operation, such as machining equipment, rotating machinery, bridges, and buildings. These vibrations contain abundant energy. If they can be effectively collected and converted into electrical energy to provide self-powered power for wireless monitoring equipment, the power supply problem of wireless monitoring equipment will be solved, and the long-term stable operation of the monitoring system can be achieved. Therefore, the use of the mechanical energy of vibration to provide self-power for acoustic emission monitoring systems has gradually begun to be used. However, when using piezoelectric ceramic sensors to provide self-power for acoustic emission monitoring systems, the self-powering cannot be sustained because the working time and frequency of the acoustic emission monitoring system are not fixed and the equipment vibration is unstable. Furthermore, the vibration of the equipment includes vibration generated by itself during operation and vibration caused by the environment. These two types of vibration are quite different, and the self-powering of a single piezoelectric ceramic sensor cannot adapt to all types of vibration, resulting in low self-powering efficiency. Summary of the Invention

[0003] The purpose of this invention is to provide a vibration self-powered acoustic emission wireless monitoring device and system to solve the problems raised in the prior art.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A vibration self-powered acoustic emission wireless monitoring system, comprising a data collection module, a self-powered module, an acoustic emission monitoring module, and a wireless communication module;

[0006] The data collection module is used to collect efficiency data of different power supply methods when the device is self-powered and vibration data when the device malfunctions, from historical records.

[0007] The self-powered module is used to store the mechanical energy of vibration converted into electrical energy using different power supply methods, and to provide self-powered operation using the stored electrical energy.

[0008] The acoustic emission monitoring module is used to collect acoustic emission signals generated during equipment operation using piezoelectric ceramic sensors, determine whether there are any abnormal risks in the equipment, and issue early warnings.

[0009] The wireless communication module is used to send an abnormal warning signal to the user's client via a wireless network when the system determines that there is an abnormal risk in the device and issues an early warning, so as to remind the user that the device has an abnormal risk and needs maintenance.

[0010] The self-powered module includes a piezoelectric self-powered unit, an electromagnetic self-powered unit, an intelligent switching unit, and an energy storage unit;

[0011] The piezoelectric self-powered unit is used to collect the mechanical energy of the device vibration by using the piezoelectric ceramic sensor. The vibration mechanical energy acts on the piezoelectric ceramic sensor, causing the piezoelectric ceramic to undergo periodic deformation. During the deformation process, the surface of the piezoelectric ceramic sensor continuously generates charges to form a potential difference and generate electrical energy. Before the piezoelectric ceramic sensor works, the self-powered vibration range of the piezoelectric ceramic sensor is calculated by using the working efficiency of the piezoelectric ceramic sensor in historical records.

[0012] The specific steps for calculating the self-powered vibration range of the piezoelectric ceramic sensor are as follows:

[0013] Vibration data and power supply efficiency of the device during the operation of the piezoelectric ceramic sensor were collected from historical records. The vibration data included vibration frequency and vibration amplitude. Scatter plots were drawn using the power supply efficiency of the piezoelectric ceramic sensor during operation from historical records as the ordinate and the device vibration amplitude and vibration frequency as the abscissas, respectively, to obtain scatter plots of power supply efficiency for two types of piezoelectric ceramic sensors. The correlation between the device vibration amplitude and vibration frequency and the power supply efficiency of the piezoelectric ceramic sensor was calculated in the two scatter plots. Specifically, the correlation calculation for vibration amplitude and power supply efficiency was as follows:

[0014] First, calculate the average of the vibration amplitude and power supply efficiency data in the scatter plot. The formula is:

[0015]

[0016] In the formula, Av p Av represents the average amplitude of vibrations in a scatter plot. i Ps represents the amplitude of vibration at each point in the scatter plot. p Ps represents the average power supply efficiency in the scatter plot. i This represents the power supply efficiency at each point in the scatter plot, where n is the total number of points in the scatter plot, and i belongs to 1 to n;

[0017] Next, the covariance between the vibration amplitude and the power supply efficiency in the scatter plot is calculated using the following formula:

[0018]

[0019] In the formula, Cov(Av, Ps) calculates the covariance of vibration amplitude and power supply efficiency in the scatter plot. The standard deviation of vibration amplitude, Av, is calculated using the average of vibration amplitude and power supply efficiency. st The standard deviation of power supply efficiency is Ps st Finally, the correlation between vibration amplitude and power supply efficiency is calculated using the following formula:

[0020]

[0021] In the formula, R(Av, Ps) represents the correlation between the calculated vibration amplitude and the power supply efficiency. The correlation between the vibration frequency and the power supply efficiency is calculated using the same method. By comparing the two correlations, the vibration data with the larger correlation is selected as the working characteristic of the piezoelectric self-powered system.

[0022] After calculating the operating characteristics of the piezoelectric self-powered circuit, the scatter plots corresponding to these characteristics are connected to form a curve. The curve is then differentiated to obtain the derivative curve of the operating characteristics. Points where the derivative is 0 are extracted from the derivative curve. The peaks and troughs adjacent to these points are then identified, and the corresponding points are used to construct the operating characteristic interval [G]. f G d The constructed operating characteristic range is taken as the optimal operating range for piezoelectric self-powered systems.

[0023] The electromagnetic self-powered unit is used to collect the vibration data of the equipment and generate electrical energy by using the vibration of the equipment to generate an induced electromotive force through electromagnetic induction.

[0024] In the electromagnetic self-powered unit, the same method as in the piezoelectric self-powered unit is used to determine the operating characteristics during electromagnetic self-powering. The derivative curve is obtained by differentiating the scatter plot of the operating characteristics. The derivative curve is analyzed to find points where the derivative is 0, and adjacent peaks and troughs are extracted. The optimal operating range for electromagnetic self-powering is then constructed as [F]. f F d ].

[0025] By analyzing and calculating the vibration data and functional efficiency of the equipment during operation in historical records, the optimal functional range of the two functional modes can be obtained. This can maximize the energy conversion efficiency, convert more input energy into usable electrical energy, and reduce energy waste. When the equipment is in the optimal functional range, the coordination of various related parameters is most suitable, the internal and external interference to the equipment or system is relatively small, and the desired effect can be output continuously and stably.

[0026] The intelligent switching unit is used to collect vibration data of the equipment in real time, and to select and switch the self-powered mode of the equipment using the vibration data. Specifically:

[0027] Real-time vibration data of the equipment during operation is collected, including real-time vibration amplitude and real-time vibration frequency; based on the two types of real-time vibration data, the real-time operating characteristic values ​​of the two self-powered modes, piezoelectric self-powered and inductive self-powered, are determined to be Gs and Fs, respectively.

[0028] The real-time operating characteristic value is determined by using the optimal operating range of the two power supply methods. When Gs∈[G f G d ]and When the device selects a piezoelectric self-powered unit for independent power supply, it switches to piezoelectric self-powered mode.

[0029] when And Fs∈[F f F d When [the device] selects the inductor self-powered unit for separate power supply, it switches to inductor self-powered mode;

[0030] When Gs∈[G f G d And Fs∈[F f F d When the device selects bidirectional power supply from both the piezoelectric self-powered unit and the inductive self-powered unit, it switches to a hybrid power supply mode.

[0031] The ability to freely switch between these two power supply modes based on equipment vibration better adapts to the energy harvesting needs of the equipment under various vibration conditions, ensuring continuous and stable energy collection in different vibration scenarios. Both piezoelectric ceramics and electromagnetic induction modes have their advantages when dealing with intermittent vibration. Piezoelectric ceramics may maintain a certain level of energy output for a period of time after vibration stops due to accumulated stress and other factors; electromagnetic induction, on the other hand, can respond quickly and begin collecting energy when vibration resumes. By freely switching between the two modes, the energy harvesting method can be flexibly adjusted when vibration intermittently changes, ensuring continuous power supply and avoiding power outages caused by vibration interruptions. Furthermore, the mechanism of freely switching according to vibration conditions ensures that the equipment's vibration energy is converted into electrical energy with the highest efficiency at all times, minimizing energy loss during conversion and improving overall energy conversion efficiency.

[0032] The energy storage unit includes a voltage regulation control unit and a power distribution unit;

[0033] The voltage regulation and control unit is used to convert the unstable voltage into a fixed DC voltage after the two self-powered units generate electrical energy, and then store the electrical energy of the fixed DC voltage.

[0034] The power distribution unit is used to collect data on the load of the monitoring system when the device is working. When the stored electrical energy is insufficient to provide the power required by the monitoring system, the real-time generated electrical energy is directly input into the monitoring system for power supply. When the stored electrical energy is sufficient to provide the power required by the monitoring system, the real-time generated electrical energy is input into the battery for storage, without needing to be input into the monitoring system.

[0035] When the monitoring system is self-powered, the generated electrical energy is unstable due to the instability of vibration, making it impossible to provide a stable and continuous power supply to the monitoring system. Setting up an energy storage unit can integrate the generated electrical energy to achieve a stable and continuous power supply to the monitoring system. After setting up battery storage, the equipment can rely on battery power to complete the start-up operation during periods when energy harvesting is not in progress, without waiting for the energy harvesting device to start up again to collect enough electrical energy. This improves the flexibility of equipment operation and enables it to better adapt to different working modes and needs.

[0036] The acoustic emission monitoring module includes a threshold calculation unit, an intelligent activation unit, and an early warning unit;

[0037] The threshold calculation unit includes a start threshold unit and an early warning threshold unit;

[0038] The activation threshold unit is used to collect historical vibration frequencies of the device during operation and non-operation from the data collection module, calculate the average and standard deviation of the vibration frequencies during operation and non-operation, and calculate the maximum vibration frequency limit when the device is not operating, using the formula: Zw max =Zw p +Zw st , in the formula, Zw max Zw represents the maximum vibration frequency limit when the calculated equipment is not in operation. p Zw represents the average vibration frequency when the equipment is not in operation. st This represents the standard deviation of the vibration frequency when the equipment is not in operation; the formula for calculating the minimum vibration frequency limit when the equipment is in operation is: Zg min =Zg p -Zg st In the formula, Zg min Zg represents the minimum vibration frequency limit during equipment operation. p Zg represents the average vibration frequency of the equipment during operation. st The standard deviation of the vibration frequency when the equipment is operating is given. The starting threshold of the equipment is calculated using the maximum vibration frequency limit when the equipment is not operating and the minimum vibration frequency limit when the equipment is operating, using the formula: Zy = Zg. min -Zw max Zy represents the calculated startup threshold of the device;

[0039] The warning threshold unit is used to collect historical acoustic emission signals that occurred during device operation from the data collection module, calculate the average value and standard deviation of the collected abnormal acoustic emission signals, and then calculate the warning threshold of the device using the formula: ZJ = H P -H st ZJ represents the calculated warning threshold of the device, H P H represents the average value of the acoustic emission signals that occur abnormally when the device is operating. st It represents the standard deviation of acoustic emission signals that occur when the calculated device is operating abnormally.

[0040] The intelligent start-up unit is used to collect the vibration frequency of the equipment in real time, analyze the change amplitude of the real-time vibration frequency of the equipment, and obtain the change amplitude of the real-time vibration frequency of the equipment as Fzs; it uses the start-up threshold to judge the change amplitude of the real-time vibration frequency. When Fzs≥Zy, it is determined that the equipment has started working and the monitoring system is started to monitor the equipment in real time; when Fzs<Zy, it is determined that the equipment has not started working, the monitoring system is not started, and the monitoring system is put into a dormant state.

[0041] The early warning unit is used to collect the acoustic emission signal of the equipment in real time when it is working. When the equipment starts working and the monitoring system is activated, the real-time acoustic emission signal of the equipment is judged by the early warning threshold. Let the collected real-time acoustic emission signal of the equipment be Pzs. When Pzs < ZJ, it is judged that there is no abnormal risk of the equipment. When Pzs ≥ ZJ, it is judged that there is an abnormal risk of the equipment, and the monitoring system issues an early warning. The early warning signal of the monitoring system is transmitted to the user client by the wireless communication module.

[0042] A vibration self-powered acoustic emission wireless monitoring device, comprising a self-powered device, an acoustic emission monitoring device, and a wireless communication device;

[0043] The self-powered device is used to collect the vibration mechanical energy of the equipment and convert the mechanical energy into electrical energy to provide self-power to the acoustic emission monitoring equipment.

[0044] The acoustic emission monitoring device is used to monitor the real-time acoustic emission signal of the equipment when the equipment is working. It uses acoustic emission sensors to collect the acoustic emission signal of the equipment in real time, determine whether there is any abnormal risk in the equipment and issue an early warning.

[0045] The wireless communication device is used to send an abnormal warning signal to the user's client via a wireless network when the system determines that there is an abnormal risk in the device and issues a warning, so as to remind the user that the device has an abnormal risk and needs maintenance.

[0046] The self-powered device includes a piezoelectric self-powered device, an electromagnetic self-powered device, and an energy storage device;

[0047] The piezoelectric self-powered device is used to convert the vibration mechanical energy of the equipment into electrical energy by setting up a piezoelectric ceramic sensor. The vibration mechanical energy is used to act on the piezoelectric ceramic sensor to cause the piezoelectric ceramic to undergo periodic deformation. During the deformation process, the surface of the piezoelectric ceramic sensor continuously generates charges to form a potential difference and generate electrical energy.

[0048] The electromagnetic self-powered device is used to set up a permanent magnet and an electromagnetic induction coil. When the equipment vibrates, it causes the set permanent magnet to pass through the electromagnetic induction coil to generate electrical energy.

[0049] The energy storage device is used to set up a voltage regulator circuit and a rechargeable battery. The voltage regulator circuit stabilizes the generated voltage, and the battery stores the generated energy.

[0050] Compared with the prior art, the beneficial effects of the present invention are:

[0051] 1. This invention utilizes historical vibration data and functional efficiency analysis of the equipment during operation to calculate the optimal functional range for two functional modes, which can maximize energy conversion efficiency, convert more input energy into usable electrical energy, and reduce energy waste. When the equipment is in the optimal functional range, the coordination of various related parameters is most suitable, the internal and external interference to the equipment or system is relatively small, and it can continuously and stably output the desired effect.

[0052] 2. This invention allows for free switching between these two power supply modes based on equipment vibration, better adapting to the energy acquisition needs of the equipment under various vibration conditions and ensuring continuous and stable energy collection in different vibration scenarios. By freely switching between the two modes, the energy acquisition method can be flexibly adjusted when vibration changes intermittently, ensuring the continuity of power supply and avoiding power outages due to vibration interruptions. Attached Figure Description

[0053] Figure 1 This is a module distribution diagram of the self-powered acoustic emission wireless monitoring system for vibration of the present invention;

[0054] Figure 2 This is a connection diagram of the vibration self-powered acoustic emission wireless monitoring device of the present invention. Detailed Implementation

[0055] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0056] Example: Figures 1-2 As shown, the present invention provides a technical solution.

[0057] A vibration self-powered acoustic emission wireless monitoring system, comprising a data collection module, a self-powered module, an acoustic emission monitoring module, and a wireless communication module;

[0058] The data collection module is used to collect efficiency data of different power supply methods when the device is self-powered and vibration data when the device malfunctions, from historical records.

[0059] The self-powered module is used to store the mechanical energy of vibration converted into electrical energy using different power supply methods, and to provide self-powered operation using the stored electrical energy.

[0060] The acoustic emission monitoring module is used to collect acoustic emission signals generated during equipment operation using piezoelectric ceramic sensors, determine whether there are any abnormal risks in the equipment, and issue early warnings.

[0061] The wireless communication module is used to send an abnormal warning signal to the user's client via a wireless network when the system determines that there is an abnormal risk in the device and issues an early warning, so as to remind the user that the device has an abnormal risk and needs maintenance.

[0062] The self-powered module includes a piezoelectric self-powered unit, an electromagnetic self-powered unit, an intelligent switching unit, and an energy storage unit;

[0063] The piezoelectric self-powered unit is used to collect the mechanical energy of the device vibration by using the piezoelectric ceramic sensor. The vibration mechanical energy acts on the piezoelectric ceramic sensor, causing the piezoelectric ceramic to undergo periodic deformation. During the deformation process, the surface of the piezoelectric ceramic sensor continuously generates charges to form a potential difference and generate electrical energy. Before the piezoelectric ceramic sensor works, the self-powered vibration range of the piezoelectric ceramic sensor is calculated by using the working efficiency of the piezoelectric ceramic sensor in historical records.

[0064] The specific steps for calculating the self-powered vibration range of the piezoelectric ceramic sensor are as follows:

[0065] Vibration data and power supply efficiency of the device during the operation of the piezoelectric ceramic sensor were collected from historical records. The vibration data included vibration frequency and vibration amplitude. Scatter plots were drawn using the power supply efficiency of the piezoelectric ceramic sensor during operation from historical records as the ordinate and the device vibration amplitude and vibration frequency as the abscissas, respectively, to obtain scatter plots of power supply efficiency for two types of piezoelectric ceramic sensors. The correlation between the device vibration amplitude and vibration frequency and the power supply efficiency of the piezoelectric ceramic sensor was calculated in the two scatter plots. Specifically, the correlation calculation for vibration amplitude and power supply efficiency was as follows:

[0066] First, calculate the average of the vibration amplitude and power supply efficiency data in the scatter plot. The formula is:

[0067]

[0068] In the formula, Av p Av represents the average amplitude of vibrations in a scatter plot. i Ps represents the amplitude of vibration at each point in the scatter plot. p Ps represents the average power supply efficiency in the scatter plot. i This represents the power supply efficiency at each point in the scatter plot, where n is the total number of points in the scatter plot, and i belongs to 1 to n;

[0069] Next, the covariance between the vibration amplitude and the power supply efficiency in the scatter plot is calculated using the following formula:

[0070]

[0071] In the formula, Cov(Av, Ps) calculates the covariance of vibration amplitude and power supply efficiency in the scatter plot. The standard deviation of vibration amplitude, Av, is calculated using the average of vibration amplitude and power supply efficiency. st The standard deviation of power supply efficiency is Ps st Finally, the correlation between vibration amplitude and power supply efficiency is calculated using the following formula:

[0072]

[0073] In the formula, R(Av, Ps) represents the correlation between the calculated vibration amplitude and the power supply efficiency. The correlation between the vibration frequency and the power supply efficiency is calculated using the same method. By comparing the two correlations, the vibration data with the larger correlation is selected as the working characteristic of the piezoelectric self-powered system.

[0074] After calculating the operating characteristics of the piezoelectric self-powered circuit, the scatter plots corresponding to these characteristics are connected to form a curve. The curve is then differentiated to obtain the derivative curve of the operating characteristics. Points where the derivative is 0 are extracted from the derivative curve. The peaks and troughs adjacent to these points are then identified, and the corresponding points are used to construct the operating characteristic interval [G]. f G d The constructed operating characteristic range is taken as the optimal operating range for piezoelectric self-powered systems.

[0075] The electromagnetic self-powered unit is used to collect the vibration data of the equipment and generate electrical energy by using the vibration of the equipment to generate an induced electromotive force through electromagnetic induction.

[0076] In the electromagnetic self-powered unit, the same method as in the piezoelectric self-powered unit is used to determine the operating characteristics during electromagnetic self-powering. The derivative curve is obtained by differentiating the scatter plot of the operating characteristics. The derivative curve is analyzed to find points where the derivative is 0, and adjacent peaks and troughs are extracted. The optimal operating range for electromagnetic self-powering is then constructed as [F]. f F d ].

[0077] By analyzing and calculating the vibration data and functional efficiency of the equipment during operation in historical records, the optimal functional range of the two functional modes can be obtained. This can maximize the energy conversion efficiency, convert more input energy into usable electrical energy, and reduce energy waste. When the equipment is in the optimal functional range, the coordination of various related parameters is most suitable, the internal and external interference to the equipment or system is relatively small, and the desired effect can be output continuously and stably.

[0078] The intelligent switching unit is used to collect vibration data of the equipment in real time, and to select and switch the self-powered mode of the equipment using the vibration data. Specifically:

[0079] Real-time vibration data of the equipment during operation is collected, including real-time vibration amplitude and real-time vibration frequency; based on the two types of real-time vibration data, the real-time operating characteristic values ​​of the two self-powered modes, piezoelectric self-powered and inductive self-powered, are determined to be Gs and Fs, respectively.

[0080] The real-time operating characteristic value is determined by using the optimal operating range of the two power supply methods. When Gs∈[G f G d ]and When the device selects a piezoelectric self-powered unit for independent power supply, it switches to piezoelectric self-powered mode.

[0081] when And Fs∈[F f F d When [the device] selects the inductor self-powered unit for separate power supply, it switches to inductor self-powered mode;

[0082] When Gs∈[G f G d And Fs∈[F f F d When the device selects bidirectional power supply from both the piezoelectric self-powered unit and the inductive self-powered unit, it switches to a hybrid power supply mode.

[0083] The ability to freely switch between these two power supply modes based on equipment vibration better adapts to the energy harvesting needs of the equipment under various vibration conditions, ensuring continuous and stable energy collection in different vibration scenarios. Both piezoelectric ceramics and electromagnetic induction modes have their advantages when dealing with intermittent vibration. Piezoelectric ceramics may maintain a certain level of energy output for a period of time after vibration stops due to accumulated stress and other factors; electromagnetic induction, on the other hand, can respond quickly and begin collecting energy when vibration resumes. By freely switching between the two modes, the energy harvesting method can be flexibly adjusted when vibration intermittently changes, ensuring continuous power supply and avoiding power outages caused by vibration interruptions. Furthermore, the mechanism of freely switching according to vibration conditions ensures that the equipment's vibration energy is converted into electrical energy with the highest efficiency at all times, minimizing energy loss during conversion and improving overall energy conversion efficiency.

[0084] The energy storage unit includes a voltage regulation control unit and a power distribution unit;

[0085] The voltage regulation and control unit is used to convert the unstable voltage into a fixed DC voltage after the two self-powered units generate electrical energy, and then store the electrical energy of the fixed DC voltage.

[0086] The power distribution unit is used to collect data on the load of the monitoring system when the device is working. When the stored electrical energy is insufficient to provide the power required by the monitoring system, the real-time generated electrical energy is directly input into the monitoring system for power supply. When the stored electrical energy is sufficient to provide the power required by the monitoring system, the real-time generated electrical energy is input into the battery for storage, without needing to be input into the monitoring system.

[0087] When the monitoring system is self-powered, the generated electrical energy is unstable due to the instability of vibration, making it impossible to provide a stable and continuous power supply to the monitoring system. Setting up an energy storage unit can integrate the generated electrical energy to achieve a stable and continuous power supply to the monitoring system. After setting up battery storage, the equipment can rely on battery power to complete the start-up operation during periods when energy harvesting is not in progress, without waiting for the energy harvesting device to start up again to collect enough electrical energy. This improves the flexibility of equipment operation and enables it to better adapt to different working modes and needs.

[0088] The acoustic emission monitoring module includes a threshold calculation unit, an intelligent activation unit, and an early warning unit;

[0089] The threshold calculation unit includes a start threshold unit and an early warning threshold unit;

[0090] The activation threshold unit is used to collect historical vibration frequencies of the device during operation and non-operation from the data collection module, calculate the average and standard deviation of the vibration frequencies during operation and non-operation, and calculate the maximum vibration frequency limit when the device is not operating, using the formula: Zw max =Zw p +Zw st , in the formula, Zw max Zw represents the maximum vibration frequency limit when the calculated equipment is not in operation. p Zw represents the average vibration frequency when the equipment is not in operation. st This represents the standard deviation of the vibration frequency when the equipment is not in operation; the formula for calculating the minimum vibration frequency limit when the equipment is in operation is: Zg min =Zg p -Zg st In the formula, Zg min Zg represents the minimum vibration frequency limit during equipment operation. p Zg represents the average vibration frequency of the equipment during operation. st The standard deviation of the vibration frequency when the equipment is operating is given. The starting threshold of the equipment is calculated using the maximum vibration frequency limit when the equipment is not operating and the minimum vibration frequency limit when the equipment is operating, using the formula: Zy = Zg. min -Zw max Zy represents the calculated startup threshold of the device;

[0091] The warning threshold unit is used to collect historical acoustic emission signals that occurred during device operation from the data collection module, calculate the average value and standard deviation of the collected abnormal acoustic emission signals, and then calculate the warning threshold of the device using the formula: ZJ = H P -H st ZJ represents the calculated warning threshold of the device, H P H represents the average value of the acoustic emission signals that occur abnormally when the device is operating. st It represents the standard deviation of acoustic emission signals that occur when the calculated device is operating abnormally.

[0092] The intelligent start-up unit is used to collect the vibration frequency of the equipment in real time, analyze the change amplitude of the real-time vibration frequency of the equipment, and obtain the change amplitude of the real-time vibration frequency of the equipment as Fzs; it uses the start-up threshold to judge the change amplitude of the real-time vibration frequency. When Fzs≥Zy, it is determined that the equipment has started working and the monitoring system is started to monitor the equipment in real time; when Fzs<Zy, it is determined that the equipment has not started working, the monitoring system is not started, and the monitoring system is put into a dormant state.

[0093] The early warning unit is used to collect the acoustic emission signal of the equipment in real time when it is working. When the equipment starts working and the monitoring system is activated, the real-time acoustic emission signal of the equipment is judged by the early warning threshold. Let the collected real-time acoustic emission signal of the equipment be Pzs. When Pzs < ZJ, it is judged that there is no abnormal risk of the equipment. When Pzs ≥ ZJ, it is judged that there is an abnormal risk of the equipment, and the monitoring system issues an early warning. The early warning signal of the monitoring system is transmitted to the user client by the wireless communication module.

[0094] A vibration self-powered acoustic emission wireless monitoring device, comprising a self-powered device, an acoustic emission monitoring device, and a wireless communication device;

[0095] The self-powered device is used to collect the vibration mechanical energy of the equipment and convert the mechanical energy into electrical energy to provide self-power to the acoustic emission monitoring equipment.

[0096] The acoustic emission monitoring device is used to monitor the real-time acoustic emission signal of the equipment when the equipment is working. It uses acoustic emission sensors to collect the acoustic emission signal of the equipment in real time, determine whether there is any abnormal risk in the equipment and issue an early warning.

[0097] The wireless communication device is used to send an abnormal warning signal to the user's client via a wireless network when the system determines that there is an abnormal risk in the device and issues a warning, so as to remind the user that the device has an abnormal risk and needs maintenance.

[0098] The self-powered device includes a piezoelectric self-powered device, an electromagnetic self-powered device, and an energy storage device;

[0099] The piezoelectric self-powered device is used to convert the vibration mechanical energy of the equipment into electrical energy by setting up a piezoelectric ceramic sensor. The vibration mechanical energy is used to act on the piezoelectric ceramic sensor to cause the piezoelectric ceramic to undergo periodic deformation. During the deformation process, the surface of the piezoelectric ceramic sensor continuously generates charges to form a potential difference and generate electrical energy.

[0100] The electromagnetic self-powered device is used to set up a permanent magnet and an electromagnetic induction coil. When the equipment vibrates, it causes the set permanent magnet to pass through the electromagnetic induction coil to generate electrical energy.

[0101] The energy storage device is used to set up a voltage regulator circuit and a rechargeable battery. The voltage regulator circuit stabilizes the generated voltage, and the battery stores the generated energy.

[0102] Example: A self-powered acoustic emission monitoring system is designed. Based on the vibration data and power supply efficiency of the monitored equipment in historical records, the operating characteristic of the piezoelectric sensor is calculated as vibration frequency, and the operating characteristic of the electromagnetic induction self-powered system is vibration amplitude. The optimal operating range of the piezoelectric sensor's vibration frequency is [30, 60], and the optimal operating range of the electromagnetic induction self-powered system's vibration amplitude is [10, 18]. Based on the equipment's operating conditions in historical records, the start-up threshold of the acoustic emission monitoring system is 20, and the warning threshold is 25.

[0103] The vibration frequency of the real-time acquisition device is 32 and the vibration amplitude is 15. Based on the judgment, it is found that both the piezoelectric sensor and the electromagnetic induction self-powered device are in the optimal working range. The hybrid power supply mode is executed, and the electrical energy generated by the vibration of the device is stored.

[0104] If the real-time vibration frequency of the equipment is found to be greater than the activation threshold, the acoustic emission monitoring system is activated to monitor the acoustic emission signal of the equipment. Let's assume the real-time acoustic emission signal is 26. If an abnormal risk is detected in the equipment, an early warning is issued. The early warning signal is then transmitted to the user client via a wireless communication device to remind the user that there is an abnormal risk in the equipment.

[0105] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A vibration-powered acoustic emission wireless monitoring system, characterized in that: The acoustic emission wireless monitoring system includes a data collection module, a self-powered module, an acoustic emission monitoring module, and a wireless communication module; The data collection module is used to collect efficiency data of different power supply methods when the device is self-powered and vibration data when the device malfunctions, from historical records. The self-powered module is used to convert the mechanical energy of vibration into electrical energy for storage using different power supply methods, and to provide self-power when the system is working using the stored electrical energy. The self-powered module includes a piezoelectric self-powered unit, an electromagnetic self-powered unit, an intelligent switching unit, and an energy storage unit; The piezoelectric self-powered unit is used to collect the mechanical energy of the device vibration by using the piezoelectric ceramic sensor. The vibration mechanical energy acts on the piezoelectric ceramic sensor, causing the piezoelectric ceramic to undergo periodic deformation. During the deformation process, the surface of the piezoelectric ceramic sensor continuously generates charges to form a potential difference and generate electrical energy. Before the piezoelectric ceramic sensor works, the self-powered vibration range of the piezoelectric ceramic sensor is calculated by using the working efficiency of the piezoelectric ceramic sensor in historical records. The specific steps for calculating the self-powered vibration range of the piezoelectric ceramic sensor are as follows: Vibration data and power supply efficiency of the device during the operation of the piezoelectric ceramic sensor were collected from historical records. The vibration data included vibration frequency and vibration amplitude. Scatter plots were drawn using the power supply efficiency of the piezoelectric ceramic sensor during operation from historical records as the ordinate and the device vibration amplitude and vibration frequency as the abscissas, respectively, to obtain scatter plots of power supply efficiency for two types of piezoelectric ceramic sensors. The correlation between the device vibration amplitude and vibration frequency and the power supply efficiency of the piezoelectric ceramic sensor was calculated in the two scatter plots. Specifically, the correlation calculation for vibration amplitude and power supply efficiency was as follows: First, calculate the average of the vibration amplitude and power supply efficiency data in the scatter plot. The formula is: ， ； In the formula, This represents the average amplitude of vibrations in the scatter plot. This represents the amplitude of vibration at each point in the scatter plot. This represents the average power supply efficiency in the scatter plot. This represents the power supply efficiency at each point in the scatter plot, where n is the total number of points in the scatter plot, and i belongs to 1 to n; Next, the covariance between the vibration amplitude and the power supply efficiency in the scatter plot is calculated using the following formula: ； In the formula, The covariance of vibration amplitude and power supply efficiency in the calculated scatter plot is used to calculate the standard deviation of vibration amplitude using the average values ​​of vibration amplitude and power supply efficiency. The standard deviation of power supply efficiency is Finally, the correlation between vibration amplitude and power supply efficiency is calculated using the following formula: ； In the formula, The correlation between the calculated vibration amplitude and the power supply efficiency is shown. The correlation between the vibration frequency and the power supply efficiency is calculated using the same method. The two correlations are compared, and the vibration data with the greater correlation is selected as the working characteristic of the piezoelectric self-powered system. After calculating the operating characteristics of the piezoelectric self-powered circuit, the scatter plots corresponding to these characteristics are connected to form a curve. The curve is then differentiated to obtain the derivative curve of the operating characteristics. Points where the derivative is zero are extracted from the derivative curve. The peaks and troughs adjacent to these zero points are then identified, and the corresponding points are used to construct the operating characteristic interval. The constructed operating characteristic range is taken as the optimal operating range for piezoelectric self-powered systems. The electromagnetic self-powered unit is used to collect vibration data of the equipment and generate electrical energy by using the vibration of the equipment to generate an induced electromotive force through electromagnetic induction. In the electromagnetic self-powered unit, the same method as in the piezoelectric self-powered unit is used to determine the operating characteristics during electromagnetic self-powering. The derivative curve is obtained by differentiating the scatter plot of the operating characteristics. Analysis of the derivative curve identifies points where the derivative is zero, and adjacent peaks and troughs are extracted to construct the optimal operating range for electromagnetic self-powering. ; The intelligent switching unit is used to collect vibration data of the equipment in real time, and to select and switch the self-powered mode of the equipment using the vibration data. Specifically: Real-time vibration data of the equipment during operation is collected, including real-time vibration amplitude and real-time vibration frequency; based on the two types of real-time vibration data, the real-time operating characteristic values ​​of the two self-powered power supply methods, piezoelectric self-powered and electromagnetic self-powered, are determined to be Gs and Fs, respectively. The real-time operating characteristic values ​​are determined by utilizing the optimal operating range of the two power supply methods. and When the device selects a piezoelectric self-powered unit for independent power supply, it switches to piezoelectric self-powered mode. when and When the device selects the electromagnetic self-powered unit for independent power supply, it switches to electromagnetic self-powered mode. when and When the device selects bidirectional power supply from both the piezoelectric self-powered unit and the electromagnetic self-powered unit, it switches to a hybrid power supply mode. The acoustic emission monitoring module is used to collect acoustic emission signals generated during equipment operation using piezoelectric ceramic sensors, determine whether there are any abnormal risks in the equipment, and issue early warnings. The wireless communication module is used to send an abnormal warning signal to the user's client via a wireless network when the system determines that there is an abnormal risk in the device and issues an early warning, so as to remind the user that the device has an abnormal risk and needs maintenance.

2. The vibration self-powered acoustic emission wireless monitoring system according to claim 1, characterized in that: The energy storage unit includes a voltage regulation control unit and a power distribution unit; The voltage regulation and control unit is used to convert the unstable voltage into a fixed DC voltage after the two self-powered units generate electrical energy, and then store the electrical energy of the fixed DC voltage. The power distribution unit is used to collect data on the load of the monitoring system when the equipment is working. When the stored electrical energy is insufficient to provide the electrical energy required by the monitoring system, the real-time generated electrical energy is directly input into the monitoring system for power supply. When the stored electrical energy is sufficient to provide the power required by the monitoring system, the generated electrical energy is input into the battery for storage, without needing to be input into the monitoring system.

3. The vibration self-powered acoustic emission wireless monitoring system according to claim 1, characterized in that: The acoustic emission monitoring module includes a threshold calculation unit, an intelligent activation unit, and an early warning unit; The threshold calculation unit includes a start threshold unit and an early warning threshold unit; The activation threshold unit is used to collect historical vibration frequencies of the device during operation and non-operation from the data collection module, calculate the average and standard deviation of the vibration frequencies during operation and non-operation, and calculate the maximum vibration frequency limit when the device is not operating, using the following formula: , in the formula, This represents the maximum vibration frequency limit when the calculated equipment is not in operation. This represents the average vibration frequency when the equipment is not in operation. This represents the standard deviation of the vibration frequency when the equipment is not in operation; the formula for calculating the minimum vibration frequency limit when the equipment is in operation is: , in the formula, This indicates the minimum vibration frequency limit when the equipment is operating. This represents the average vibration frequency of the equipment during operation. The standard deviation of the vibration frequency when the equipment is operating is represented by the standard deviation of the vibration frequency. The starting threshold of the equipment is calculated using the maximum vibration frequency limit when the equipment is not operating and the minimum vibration frequency limit when the equipment is operating, using the following formula: , This indicates the calculated startup threshold of the device; The warning threshold unit is used to collect historical acoustic emission signals that occurred during device operation from the data collection module, calculate the average value and standard deviation of the collected abnormal acoustic emission signals, and then calculate the warning threshold of the device. The formula is as follows: , This indicates the warning threshold of the calculated device. This represents the average value of acoustic emission signals that occur when the device is operating abnormally. It represents the standard deviation of acoustic emission signals that occur when the calculated device is operating abnormally.

4. The vibration self-powered acoustic emission wireless monitoring system according to claim 3, characterized in that: The intelligent start unit is used to collect the vibration frequency of the equipment in real time, analyze the change amplitude of the real-time vibration frequency, and obtain the change amplitude of the real-time vibration frequency as Fzs; it uses a start threshold to judge the change amplitude of the real-time vibration frequency, and when... To determine if the equipment has started working, the monitoring system is activated to monitor the equipment in real time; when If the system is not in operation, the monitoring system will not be activated and will be placed in a dormant state.

5. The vibration self-powered acoustic emission wireless monitoring system according to claim 4, characterized in that: The early warning unit is used to collect the acoustic emission signal of the equipment in real time during operation. When the equipment starts working and the monitoring system is activated, the early warning threshold is used to judge the real-time acoustic emission signal of the equipment during operation. Let the collected real-time acoustic emission signal of the equipment during operation be Pzs. When, it is determined that the equipment does not pose an abnormal risk; when When an abnormal risk is detected in the equipment, the monitoring system issues an early warning; and uses a wireless communication module to transmit the early warning signal from the monitoring system to the user client.

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