Piezoelectric emergency charging control method

Abstract

The application discloses a piezoelectric emergency charging control method, and relates to the technical field of charging. The method comprises the following steps: when there is no external power supply or the power supply is insufficient, collecting environmental noise and gathering the noise to a piezoelectric transducing unit, generating electric energy after frequency band identification and matching, and rectifying, filtering and stabilizing the voltage; comparing the energy-taking current with the system current, executing energy storage or power supply, and starting emergency output when the equipment has low power or requests charging. The application continuously gathers environmental noise and vibration energy caused by the noise through an acoustic collection structure when there is no external power supply or the external power supply is insufficient, and forms an original electric energy signal by the piezoelectric transducing unit, so that the environmental noise which has not been utilized is converted into electric energy which can be used for power supply or energy storage. The application can realize passive and autonomous energy taking in the scenes of sudden power failure, field operation, disaster emergency and the like, and reduces the risk of equipment power failure caused by the lack of external energy supply.

Description

Technical Field

[0001] This invention relates to the field of charging technology, and in particular to a piezoelectric emergency charging control method. Background Technology

[0002] With the increasing use of portable electronic devices, emergency terminals, and sensing devices in scenarios such as field operations, disaster relief, factory inspections, and traffic monitoring, these devices often rely on lithium batteries, adapters for mains charging, or portable power banks for power when there is a sudden power outage, no mains power coverage, or insufficient external power supply. However, these power supply methods usually require pre-stored energy or rely on external power sources. In emergency environments without replenishment for extended periods, they are prone to problems such as running out of power, device shutdown, data interruption, or failure of emergency functions, making it difficult to meet continuous emergency power supply needs.

[0003] Existing emergency charging solutions mostly focus on increasing battery capacity, external power supply, or configuring mobile energy storage devices, while neglecting the utilization of persistent environmental noise energy. Factory equipment operating noise, traffic noise, mechanical operation noise, and ambient noise from people typically exist in the form of stray sound waves and vibrations, and are often not effectively recovered and utilized. Although piezoelectric transducer technology can convert mechanical vibrations into electrical energy, in actual emergency scenarios, environmental noise is characterized by unstable intensity, large frequency distribution variations, and significant fluctuations in output power. Simply extracting energy from a fixed frequency band or using simple piezoelectric power generation is insufficient to achieve stable charging output. Therefore, we propose a piezoelectric emergency charging control method. Summary of the Invention

[0004] The purpose of this invention is to provide a piezoelectric emergency charging control method to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a piezoelectric emergency charging control method, comprising: In emergency scenarios where there is no external power supply or the external power supply is insufficient, the acoustic acquisition structure is controlled to enter the standby acquisition state, and the ambient noise sound waves and the vibration energy they cause are gathered to the piezoelectric transducer unit. The environmental noise is frequency band identified to determine the noise frequency band with the most concentrated energy in the current environment, and the vibration matching state of the piezoelectric transducer is controlled accordingly so that the acoustic mechanical vibration continuously acts on the piezoelectric transducer and forms the original electrical energy signal. The original electrical signal is rectified, filtered, and regulated to obtain DC power for power supply or energy storage. Based on the relationship between the current that can be provided by the current noise energy harvesting and the current required by the system, the surplus electrical energy is selected to be stored in the energy storage module, or the DC power is directly used to supply power and the original system power supply makes up for the shortfall. When an emergency charging need is detected in an external device, or when an external device is detected to be in a low battery state, the charging output circuit is activated to provide emergency charging power to the external device.

[0006] Preferably, the control of the acoustic acquisition structure to enter the standby acquisition state includes: after the device is powered on, performing initialization self-test and parameter configuration to confirm that the acoustic acquisition structure, piezoelectric transducer, power processing part and energy storage module are in a working state, and then allowing the acoustic acquisition structure to continuously acquire environmental noise sound waves and vibration energy.

[0007] Preferably, determining the noise frequency band with the most concentrated energy in the current environment includes: collecting sound signals through a microphone or collecting vibration signals through an accelerometer, ensuring that the sampling rate meets the sampling requirements of the highest noise frequency to be identified, and then performing frequency domain analysis on the collected signals.

[0008] Preferably, before performing frequency domain analysis on the acquired signal, the acquired signal is sequentially subjected to mean removal, trend removal, anti-aliasing filtering, and windowing processing to reduce the impact of background drift, low-frequency trend terms, aliasing interference, and spectral leakage on the noise band identification results.

[0009] Preferably, the frequency domain analysis uses Fast Fourier Transform or Discrete Fourier Transform to obtain the amplitude spectrum, and determines the spectral peaks that are higher than the background noise reference value by a preset decibel range as significant spectral peaks. Then, the frequency corresponding to the spectral peak with the largest amplitude is selected from the significant spectral peaks as the noise frequency with the most concentrated energy in the current environment.

[0010] Preferably, controlling the vibration matching state of the piezoelectric transducer includes: adjusting the matching state of the piezoelectric transducer receiving acoustic mechanical vibration according to the noise frequency where the energy is most concentrated, so that the piezoelectric transducer continuously generates induced electrical energy under the current noise intensity variation conditions, instead of using a fixed noise frequency band as the only energy harvesting object.

[0011] Preferably, the rectification, filtering and voltage regulation process includes: first converting the original electrical signal output by the piezoelectric transducer into DC form, then filtering the DC form electrical energy to reduce noise interference, and then performing voltage regulation to ensure that the output electrical energy meets the stability requirements of subsequent energy storage or charging output.

[0012] Preferably, the selection based on the relationship between the current that can be provided by the current noise energy harvesting and the current required by the system includes: when the current that can be provided by the current noise energy harvesting is greater than the current required by the system, the surplus electrical energy after satisfying the system power supply is written into the energy storage module; when the current that can be provided by the current noise energy harvesting is not greater than the current required by the system, the DC electrical energy is given priority to directly participate in the system power supply, and the original system power supply makes up for the insufficient part.

[0013] Preferably, the step of activating the charging output circuit includes: after the external device sends a charging demand signal or the system detects that the external device has low power, allowing the DC power after voltage regulation or the power output of the energy storage module to enter the charging output circuit, and providing emergency power to portable devices, emergency terminals or sensing devices through intelligent power distribution.

[0014] Preferably, during emergency charging, the ambient noise energy extraction status, the energy storage module power status, and the charging demand status of external devices are continuously monitored; when the ambient noise energy extraction returns to a state of surplus power supply, the system switches back to energy storage supplementation control; when the ambient noise energy extraction is insufficient and the external devices still need charging, the system maintains an output state where piezoelectric energy extraction and the original system power supply are used together to maintain the continuity of emergency charging.

[0015] The technical effects and advantages of this invention are as follows: (1) This invention enables the acoustic acquisition structure to continuously collect environmental noise sound waves and the vibration energy caused by them when there is no external power supply or insufficient external power supply, and the piezoelectric transducer unit generates the original electrical energy signal, converting the originally unused environmental noise into electrical energy that can participate in power supply or energy storage. Compared with the traditional emergency charging method that relies on mains power, power bank or pre-installed battery, this invention can achieve passive autonomous energy acquisition in scenarios such as sudden power outages, field operations, disaster emergency, etc., reducing the risk of equipment power outages caused by lack of external energy supply.

[0016] (2) This invention does not directly generate piezoelectric power in a fixed state. Instead, it first identifies the frequency band of environmental noise, determines the noise frequency band with the most concentrated energy, and then controls the vibration matching state of the piezoelectric transducer. The signal is collected by a microphone or accelerometer, and significant spectral peaks are extracted by combining mean removal, trend removal, anti-aliasing filtering, windowing, and frequency domain analysis. This allows the piezoelectric transducer to adapt to changes in the frequency of environmental noise, thereby reducing the problem of unstable energy harvesting caused by noise frequency band drift or noise intensity fluctuations.

[0017] (3) The present invention rectifies, filters and stabilizes the original electrical energy obtained by piezoelectric conversion, and then distributes it according to the relationship between the current that can be provided by the current noise energy harvesting and the current required by the system: when the energy harvesting current is sufficient, it is stored in the energy storage module; when the energy harvesting current is insufficient, DC power is given priority to participate in the power supply and the original system power supply makes up the shortfall; at the same time, when the external device is detected to have a charging demand or low power state, the charging output circuit is opened, thereby forming a coordinated power supply control between noise energy harvesting, energy storage module and original system power supply, improving the continuity and stability of the emergency charging process. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a flowchart of the passive autonomous power replenishment control of the present invention; Figure 2 This is a flowchart of the noise frequency band identification and vibration matching process of the present invention; Figure 3 This is a flowchart of the continuous control process for energy storage distribution and emergency output of the present invention. Detailed Implementation

[0019] 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.

[0020] This invention provides, for example Figures 1-3 The piezoelectric emergency charging control method shown includes: In emergency scenarios where there is no external power supply or the external power supply is insufficient, the acoustic acquisition structure is controlled to enter the standby acquisition state, and the ambient noise sound waves and the vibration energy they cause are gathered to the piezoelectric transducer unit. The environmental noise frequency band is identified to determine the noise frequency band with the most concentrated energy in the current environment, and the vibration matching state of the piezoelectric transducer is controlled accordingly to make the acoustic mechanical vibration continuously act on the piezoelectric transducer and form the original electrical energy signal. The raw electrical signal is rectified, filtered, and regulated to obtain DC power for power supply or energy storage. Based on the relationship between the current that can be provided by the current noise energy harvesting and the current required by the system, the choice is to store the surplus electrical energy in the energy storage module, or to have DC power directly participate in the power supply and have the original system power supply make up for the shortfall. When an emergency charging need is detected in an external device, or when an external device is detected to be in a low battery state, the charging output circuit is activated to provide emergency charging power to the external device.

[0021] In practical implementation, this method can be applied to scenarios such as sudden power outages, field operations, disaster emergencies, and lack of mains power coverage. After the device is started, it first completes the initialization self-test and parameter configuration, so that the acoustic acquisition structure, piezoelectric transducer, power processing part and energy storage module are in working state. Then it enters the standby acquisition state. The acoustic acquisition structure continuously receives stray noise, mechanical operation noise, traffic noise or operation noise in the surrounding environment, and gathers the sound waves and the vibration energy they cause to the piezoelectric transducer, so that the piezoelectric transducer generates the original electrical energy signal under the mechanical vibration of the sound waves. Since environmental noise typically exhibits frequency variations and intensity fluctuations, this method identifies the frequency band of environmental noise during piezoelectric transduction. Specifically, it can collect sound signals through a microphone or vibration signals through an accelerometer. The collected signals undergo mean-reduction, detrending, anti-aliasing filtering, and windowing processing. The amplitude spectrum is then obtained through Fast Fourier Transform or Discrete Fourier Transform. Based on significant spectral peaks in the amplitude spectrum that are higher than the background noise reference value, the system determines the noise frequency band with the most concentrated energy in the current environment and adjusts the vibration matching state of the piezoelectric transducer accordingly. This enables the piezoelectric transducer to more effectively receive the main sound energy in the current environment, rather than relying solely on a fixed frequency band for power generation. The raw electrical signal output by the piezoelectric transducer is subject to voltage fluctuations and noise interference. Therefore, it needs to be rectified, filtered, and regulated sequentially to form a relatively stable DC power. Subsequently, the system allocates power according to the current available from the noise extraction and the current required by the system: when the current available from the noise extraction is greater than the current required by the system, the excess power after supplying the system is stored in the energy storage module; when the current available from the noise extraction is not greater than the current required by the system, the DC power directly participates in the power supply, and the insufficient part is supplemented by the original system power supply. In this way, energy storage can be achieved when the noise extraction is sufficient, and the power supply can be maintained continuously when the noise extraction is insufficient. When an external device issues an emergency charging request, or when the system detects that the external device is in a low battery state, the charging output circuit is activated, and the regulated DC power or the power in the energy storage module is output to the external device. Through the above control method, this method can convert the noise energy that was originally wasted in the environment into usable electrical energy, and provide continuous power to portable devices, emergency terminals or sensing devices when there is no external power supply or the external power supply is insufficient, thereby improving the autonomy, stability and endurance of emergency power supply.

[0022] The control of the acoustic acquisition structure to enter the standby acquisition state includes: after the device is powered on, performing initialization self-test and parameter configuration to confirm that the acoustic acquisition structure, piezoelectric transducer, power processing section and energy storage module are in a working state before allowing the acoustic acquisition structure to continuously acquire environmental noise sound waves and vibration energy.

[0023] In practical implementation, the device does not immediately enter the acoustic energy acquisition state after being powered on. Instead, the control unit first performs initialization self-test and parameter configuration. The initialization self-test may include detecting the acquisition channel of the acoustic acquisition structure, the output response of the piezoelectric transducer, the rectification and voltage regulation status of the power processing section, and the power and connection status of the energy storage module. The parameter configuration may include setting sampling parameters, noise identification threshold, energy storage switching conditions, and charging output conditions. Only after confirming that the acoustic acquisition structure can normally receive ambient noise, the piezoelectric transducer can convert sound wave vibration into electrical energy, the power processing section can perform subsequent processing on the raw electrical energy, and the energy storage module is in an accessible state, is the acoustic acquisition structure allowed to continuously acquire ambient noise sound waves and vibration energy. The above control method can prevent the device from directly entering the energy harvesting state when the acquisition channel is abnormal, the piezoelectric transducer fails, the power processing is unstable, or the energy storage module is unavailable, thereby reducing the risk of invalid acquisition and abnormal output. At the same time, the standby acquisition state is established after the self-test is qualified, so that the subsequent noise acquisition-piezoelectric transducer-voltage stabilization energy storage-emergency output process has a clear working basis, which is conducive to improving the start-up reliability and emergency charging continuity in scenarios without external power supply or with insufficient external power supply.

[0024] The process of identifying the noise frequency band with the highest energy concentration in the current environment includes: collecting sound signals through a microphone or vibration signals through an accelerometer, ensuring that the sampling rate meets the sampling requirements of the highest noise frequency to be identified, and then performing frequency domain analysis on the collected signals.

[0025] In practical implementation, after the device enters the standby acquisition state, in order to determine the main frequency band more suitable for piezoelectric energy extraction from the environmental noise, the sound signal in the surrounding environment can be collected by a microphone, or the vibration signal caused by sound waves or equipment operating noise can be collected by an accelerometer. The microphone is suitable for collecting noise sound waves propagating in the air, and the accelerometer is suitable for collecting vibration energy transmitted by the shell, bracket or mounting base. The two can be selected according to the installation location of the device and the source of noise. During the sampling process, the sampling rate is set according to the highest noise frequency to be identified, so that the sampling rate meets the sampling requirements required for frequency identification and avoids the inaccurate identification of high-frequency noise components due to insufficient sampling rate. The collected sound or vibration signals are not directly used to control the piezoelectric transducer unit, but are first entered into the frequency domain analysis process as the signal to be analyzed. By performing frequency domain analysis on the collected signal, the energy distribution of the current environmental noise in different frequency bands can be obtained, thereby determining which frequency bands correspond to more concentrated noise energy. In practice, the frequency domain analysis results can be used to extract the main noise frequency or main noise band in the current environment. When the energy of a certain frequency band is significantly higher than that of other frequency bands or higher than the background noise level, the frequency band is identified as the noise band with the most concentrated energy in the current environment. Subsequently, the control unit can adjust the vibration matching state of the piezoelectric transducer unit according to the result of the frequency band, so that the piezoelectric transducer unit can preferentially receive and convert the acoustic mechanical vibration corresponding to the main frequency band. Through the above implementation method, the piezoelectric transducer unit can avoid blindly extracting energy when the ambient noise frequency is unknown or varies greatly. Compared with the method of collecting acoustic energy only according to a fixed frequency band, this method can select a frequency band that is more conducive to energy extraction based on the frequency distribution of the actual ambient noise, thereby improving the effectiveness of acoustic energy to electrical energy conversion. At the same time, by using a microphone or accelerometer to adapt to the acoustic wave acquisition and vibration acquisition scenarios respectively, the device can enhance its adaptability to different noise sources such as factory equipment operating noise, traffic noise, and mechanical operation noise, providing a more stable energy input foundation for subsequent voltage-stabilized energy storage and emergency charging output.

[0026] Before performing frequency domain analysis on the acquired signals, the acquired signals are subjected to mean removal, detrending, anti-aliasing filtering, and windowing processing in sequence to reduce the impact of background drift, low-frequency trend terms, aliasing interference, and spectral leakage on the noise band identification results.

[0027] In practice, the acoustic and vibration signals collected by the microphone or accelerometer usually include ambient background noise, low-frequency drift of the device, aliasing components during the sampling process, and spectral leakage caused by non-complete period sampling. In order to make the subsequent frequency domain analysis more accurately reflect the distribution of the main noise energy in the current environment, this method preprocesses the collected signals before performing frequency domain analysis. Specifically, the acquired signal is first mean-removed to eliminate DC bias and prevent low-frequency interference from mean shift during subsequent spectral analysis. Then, detrending processing is performed to reduce low-frequency trend terms caused by sensor installation status, slow environmental changes, or drift during acquisition. Next, anti-aliasing filtering suppresses interference components above the effective analysis frequency band, preventing them from folding into the target frequency band after sampling and affecting the determination of the main noise frequency. Finally, the acquired signal is windowed; Hamming or Hanning windows can be used to reduce spectral leakage caused by truncated signals in frequency domain analysis. After the above processing, performing Fast Fourier Transform or Discrete Fourier Transform on the acquired signal can obtain a more stable amplitude spectrum, making the significant spectral peaks closer to the true noise frequency band. Therefore, when judging the noise frequency band with the most concentrated energy in the current environment, it can reduce misjudgments caused by background drift, low-frequency trend terms, aliasing interference, and spectral leakage, and avoid the piezoelectric transducer unit performing vibration matching based on the wrong frequency band. This method is beneficial to improving the reliability of noise frequency band identification results, enabling the piezoelectric transducer unit to receive the main noise energy more effectively, and providing a more stable raw power input for subsequent rectification and voltage regulation, energy storage distribution, and emergency charging output.

[0028] In the frequency domain analysis, the amplitude spectrum is obtained by fast Fourier transform or discrete Fourier transform, and the spectral peaks that are higher than the background noise reference value by a preset decibel range are identified as significant spectral peaks. Then, the frequency corresponding to the spectral peak with the largest amplitude is selected from the significant spectral peaks as the noise frequency with the most concentrated energy in the current environment.

[0029] In practical implementation, the preprocessed acquired signal enters the frequency domain analysis stage. The frequency domain analysis can use Fast Fourier Transform or Discrete Fourier Transform to convert the time-domain acoustic signal or vibration signal into an amplitude spectrum, thereby obtaining the energy distribution of the current environmental noise at different frequency positions. The control unit establishes a background noise reference value based on the amplitude spectrum. The background noise reference value can be determined by the average amplitude of non-significant frequency bands or the environmental noise floor value. Subsequently, spectral peaks that are higher than the background noise reference value by a preset decibel range are identified as significant spectral peaks. For example, spectral peaks that are 3 to 6 dB higher than the background noise floor value can be selected as effective candidate spectral peaks. When there are multiple significant spectral peaks in the amplitude spectrum, the control unit does not directly use the frequencies corresponding to all the peaks as the basis for piezoelectric transduction control. Instead, it further selects the peak with the largest amplitude from the significant peaks and determines the frequency corresponding to the peak as the noise frequency with the most concentrated energy in the current environment. Subsequently, this noise frequency can be used as the basis for vibration matching control of the piezoelectric transduction unit, so that the piezoelectric transduction unit can preferentially extract energy around the current main noise energy. By employing the above method, interference from background noise, occasional weak noise, or low-energy stray frequencies with the piezoelectric transducer control judgment can be avoided. This allows the device to identify the most valuable main noise frequencies even in complex noise environments such as factory equipment operation noise, traffic noise, and mechanical operation noise. Compared to methods that extract energy solely based on instantaneous noise intensity or fixed frequency bands, this implementation method improves the accuracy of noise frequency band identification, enabling the piezoelectric transducer unit to obtain more stable mechanical vibration input. This, in turn, enhances the continuity and reliability of subsequent sound energy to electrical energy conversion, voltage stabilization energy storage, and emergency charging output.

[0030] Among them, controlling the vibration matching state of the piezoelectric transducer includes: adjusting the matching state of the mechanical vibration of the piezoelectric transducer receiving acoustic waves according to the noise frequency where the energy is most concentrated, so that the piezoelectric transducer continuously generates induced electrical energy under the current noise intensity variation conditions, instead of using a fixed noise frequency band as the only energy harvesting object.

[0031] In practical implementation, after the control unit completes the noise frequency band identification and obtains the noise frequency with the most concentrated energy in the current environment, it uses the noise frequency as the control basis for the piezoelectric transducer to receive sound energy and convert vibration. Since the environmental noise is not a constant sound source, its sources may include mechanical operation noise, traffic noise, work noise or crowd environmental noise. The noise intensity and frequency distribution will change in different scenarios. Therefore, the piezoelectric transducer does not use a preset fixed frequency band as the only energy source, but adjusts the matching state of its received sound wave mechanical vibration according to the identified main noise frequency, so that the mechanical vibration caused by the environmental sound wave can act on the piezoelectric transducer more continuously. During implementation, when the frequency domain analysis results show that the main noise frequency changes, the control unit can re-use the frequency corresponding to the most significant spectral peak with the current amplitude as the new matching basis, so that the piezoelectric transducer can adapt to changes in environmental noise. When the noise intensity increases, the piezoelectric transducer continues to receive the vibration energy of the main frequency band and forms a strong original electrical energy signal. When the noise intensity decreases, the piezoelectric transducer can still maintain the energy harvesting state by identifying and matching the main noise frequency, so as to avoid power generation interruption or significant reduction due to the noise frequency band deviating from the fixed energy harvesting range. Through the above implementation methods, this method can link the noise frequency identification results with the piezoelectric energy conversion control process, enabling the piezoelectric energy conversion unit to extract energy around the noise frequency band with greater energy advantage in the current environment. Compared with the method of generating piezoelectric power by relying solely on a fixed frequency band or fixed vibration state, this method can improve the adaptability between acoustic energy input and piezoelectric energy conversion process in complex noise environments, reduce the impact of noise frequency drift and noise intensity fluctuations on power generation stability, thereby improving the continuity of the original electrical energy signal and providing a more reliable energy source for subsequent rectification, filtering, voltage stabilization, energy storage distribution, and emergency charging output.

[0032] The rectification, filtering, and voltage regulation processes include: first, converting the original electrical signal output by the piezoelectric transducer into DC form; then, filtering the DC form electrical energy to reduce noise interference; and finally, performing voltage regulation to ensure that the output electrical energy meets the stability requirements for subsequent energy storage or charging output.

[0033] In practical implementation, the original electrical signal output by the piezoelectric transducer under the action of acoustic mechanical vibration is usually an electrical signal whose amplitude fluctuates with the noise level, making it difficult to use directly for energy storage or external charging. Therefore, this method first converts the original electrical signal into DC form through rectification, so that the electrical energy generated by the piezoelectric transducer is suitable for subsequent use. Then, the DC form electrical energy is filtered to reduce noise environment changes, transducer vibration instability, or noise interference generated during circuit conversion. Finally, voltage stabilization is performed to keep the output voltage within a range suitable for the energy storage module to receive or for the charging output circuit to operate. By employing the above-mentioned processing methods, the large fluctuations in the output power of the piezoelectric transducer can be avoided from directly affecting the charging safety of the energy storage module or the charging stability of external devices. This ensures that the power obtained from the conversion of environmental noise is properly regulated before entering the energy storage distribution and emergency output. As a result, this method can improve the availability and output reliability of noise-triggered power, providing a stable DC power foundation for subsequent surplus power storage, emergency power replenishment for low power levels, and continuous power supply control.

[0034] The selection is based on the relationship between the current that can be provided by the current noise energy harvesting and the current required by the system. This includes: when the current that can be provided by the current noise energy harvesting is greater than the current required by the system, the surplus power after the system power supply is met is written into the energy storage module; when the current that can be provided by the current noise energy harvesting is not greater than the current required by the system, DC power is given priority to participate directly in the system power supply, and the original system power supply makes up for the shortfall.

[0035] In practical implementation, the control unit obtains the current that can be provided by the current noise energy extraction in real time and compares it with the current required by the system. The current that can be provided by the current noise energy extraction can be recorded as Iz, and the current required by the system can be recorded as I0. When Iz > I0, it means that the DC power output by the piezoelectric transducer after rectification, filtering and voltage regulation can not only meet the current power supply needs of the system, but also has surplus power. At this time, the control unit will import the surplus part after meeting the power supply needs of the system into the energy storage module, so that the energy storage module can complete the energy replenishment and storage when the noise energy is sufficient. When Iz≤I0, it means that the current ambient noise energy harvesting is insufficient to meet the system power supply demand alone. At this time, the control unit no longer prioritizes energy storage, but allows the DC power after voltage regulation to directly participate in the system power supply, and the original system power supply makes up for the insufficient part. In this way, it can utilize the available noise energy harvesting, and avoid insufficient system power supply or emergency output interruption due to forced energy storage. Through the above-mentioned current comparison and distribution control method, this method can switch between energy storage supplementation and direct power supply according to the changes in the energy extraction capacity of environmental noise. When the noise energy is sufficient, the energy storage module's reserve capacity is improved, and when the noise energy is insufficient, the system's continuous operation is ensured, thereby improving the power supply stability and emergency endurance capability of the piezoelectric emergency charging device in complex noise environments.

[0036] The activation of the charging output circuit includes: after an external device sends a charging demand signal or the system detects that the external device has low power, allowing the DC power or energy storage module outputting power after voltage regulation to enter the charging output circuit, and providing emergency power to portable devices, emergency terminals or sensing devices through intelligent power distribution.

[0037] In practice, the charging output circuit is not always open. It is only allowed to conduct when the external device has an actual power replenishment need. Specifically, when the external device actively sends a charging demand signal, or when the system detects that the power of the external device is lower than the preset low power threshold, the control unit determines to enter the emergency charging output stage. At this time, depending on the front-end energy harvesting and energy storage status, it can choose to directly enter the charging output circuit with DC power after voltage regulation, or choose to enter the charging output circuit with power output from the energy storage module. Alternatively, it can coordinate the output through intelligent power distribution when both are available. During the output process, the control unit allocates the output power according to the charging needs of the external device, the current noise-derived power, and the power status of the energy storage module, so that portable devices, emergency terminals, or sensing devices can obtain relatively stable emergency power. When the noise-derived power is sufficient, the DC power obtained in real time can be used for charging first. When the noise-derived power is insufficient or fluctuates greatly, the energy storage module can participate in the output to reduce the impact of environmental noise changes on the charging continuity. By employing the above methods, this approach can avoid ineffective output when external devices have no charging needs, thereby reducing energy storage consumption. Simultaneously, it can promptly activate the output circuit upon detecting low battery levels or emergency charging needs, enabling the coordinated utilization of noise-triggered and stored energy. This, in turn, improves the battery life and charging output stability of emergency devices in scenarios without mains power.

[0038] During emergency charging, the system continuously monitors the environmental noise energy extraction status, the energy storage module's power status, and the charging demand status of external devices. When the environmental noise energy extraction returns to a state of surplus power supply, it switches back to energy storage supplementation control. When the environmental noise energy extraction is insufficient and external devices still need charging, it maintains an output state where piezoelectric energy extraction and the original system power supply are used together to ensure the continuity of emergency charging.

[0039] In practical implementation, after the device enters the emergency charging output stage, the control unit does not continuously output based on a single judgment result, but continuously monitors the environmental noise energy harvesting status, the energy storage module's power status, and the charging demand status of external devices. The environmental noise energy harvesting status can be reflected by the current piezoelectric energy harvesting current and the regulated DC output status; the energy storage module's power status is used to determine whether the energy storage module has the conditions to participate in energy replenishment or continue to store energy; the external device charging demand status is used to determine whether the external device is still in a low power state or requests charging. When increased ambient noise is detected, causing the current supplied by the current noise energy extraction to exceed the current required by the system, the control unit will re-introduce the surplus power after power supply into the energy storage module, so that the device switches from a simple output state to energy storage supplementation control. This increases the subsequent emergency backup power when the sound energy is sufficient. When insufficient ambient noise energy extraction is detected, but the external device still has a charging demand, the control unit maintains the piezoelectric energy extraction to directly participate in the power supply, and the original system power supply makes up for the insufficient part, so as to avoid the interruption of charging output due to noise fluctuations. Through continuous monitoring and state switching, this method can dynamically adjust the relationship between energy storage replenishment and common power supply according to changes in the energy extraction capacity of environmental noise and the demand of external equipment. This not only improves the utilization rate of environmental noise power, but also ensures the continuity and stability of the emergency charging process.

[0040] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A piezoelectric emergency charging control method, characterized in that, include: In emergency scenarios where there is no external power supply or the external power supply is insufficient, the acoustic acquisition structure is controlled to enter the standby acquisition state, and the ambient noise sound waves and the vibration energy they cause are gathered to the piezoelectric transducer unit. The environmental noise is frequency band identified to determine the noise frequency band with the most concentrated energy in the current environment, and the vibration matching state of the piezoelectric transducer is controlled accordingly so that the acoustic mechanical vibration continuously acts on the piezoelectric transducer and forms the original electrical energy signal. The original electrical signal is rectified, filtered, and regulated to obtain DC power for power supply or energy storage. Based on the relationship between the current that can be provided by the current noise energy harvesting and the current required by the system, the surplus electrical energy is selected to be stored in the energy storage module, or the DC power is directly used to supply power and the original system power supply makes up for the shortfall. When an emergency charging need is detected in an external device, or when an external device is detected to be in a low battery state, the charging output circuit is activated to provide emergency charging power to the external device.

2. The piezoelectric emergency charging control method according to claim 1, characterized in that: The control of the acoustic acquisition structure to enter the standby acquisition state includes: after the device is powered on, performing initialization self-test and parameter configuration to confirm that the acoustic acquisition structure, piezoelectric transducer, power processing part and energy storage module are in a working state, and then allowing the acoustic acquisition structure to continuously acquire environmental noise sound waves and vibration energy.

3. The piezoelectric emergency charging control method according to claim 1, characterized in that: The process of determining the noise frequency band with the most concentrated energy in the current environment includes: collecting sound signals through a microphone or vibration signals through an accelerometer, ensuring that the sampling rate meets the sampling requirements of the highest noise frequency to be identified, and then performing frequency domain analysis on the collected signals.

4. The piezoelectric emergency charging control method according to claim 3, characterized in that: Before performing frequency domain analysis on the acquired signal, the acquired signal is subjected to mean removal, trend removal, anti-aliasing filtering, and windowing processing in sequence to reduce the impact of background drift, low-frequency trend terms, aliasing interference, and spectral leakage on the noise band identification results.

5. The piezoelectric emergency charging control method according to claim 4, characterized in that: The frequency domain analysis uses Fast Fourier Transform or Discrete Fourier Transform to obtain the amplitude spectrum, and determines the spectral peaks that are higher than the background noise reference value by a preset decibel range as significant spectral peaks. Then, the frequency corresponding to the spectral peak with the largest amplitude is selected from the significant spectral peaks as the noise frequency with the most concentrated energy in the current environment.

6. The piezoelectric emergency charging control method according to claim 5, characterized in that: The vibration matching state of the piezoelectric transducer unit is controlled by adjusting the matching state of the piezoelectric transducer unit receiving acoustic mechanical vibration according to the noise frequency where the energy is most concentrated, so that the piezoelectric transducer unit continuously generates induced electrical energy under the current noise intensity variation conditions, instead of using a fixed noise frequency band as the only energy source.

7. The piezoelectric emergency charging control method according to claim 1, characterized in that: The rectification, filtering, and voltage regulation processes include: first, converting the original electrical signal output by the piezoelectric transducer into DC form; then, filtering the DC form electrical energy to reduce noise interference; and finally, performing voltage regulation to ensure that the output electrical energy meets the stability requirements for subsequent energy storage or charging output.

8. The piezoelectric emergency charging control method according to claim 1, characterized in that: The selection based on the relationship between the current that can be provided by the current noise energy harvesting and the current required by the system includes: when the current that can be provided by the current noise energy harvesting is greater than the current required by the system, the surplus electrical energy after satisfying the system power supply is written into the energy storage module; when the current that can be provided by the current noise energy harvesting is not greater than the current required by the system, the DC electrical energy is given priority to directly participate in the system power supply, and the original system power supply makes up for the insufficient part.

9. The piezoelectric emergency charging control method according to claim 1, characterized in that: The activation of the charging output circuit includes: after the external device sends a charging demand signal or the system detects that the external device has low power, allowing the DC power or energy storage module output power after voltage regulation to enter the charging output circuit, and providing emergency power to portable devices, emergency terminals or sensing devices through intelligent power distribution.

10. The piezoelectric emergency charging control method according to claim 1, characterized in that: During emergency charging, the ambient noise energy extraction status, the energy storage module power status, and the charging demand status of external devices are continuously monitored. When the ambient noise energy extraction returns to a state of surplus power supply, the system switches back to energy storage supplementation control. When the ambient noise energy extraction is insufficient and the external devices still need charging, the system maintains an output state where piezoelectric energy extraction and the original system power supply are used together to maintain the continuity of emergency charging.

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