阅读说明：本技术 基于频率自适应的噪声发电系统及其自适应控制方法 (Noise power generation system based on frequency self-adaptation and self-adaptation control method thereof ) 是由 余乐 刘送进 邢荣达 王靖傲 孙秋野 于 2021-08-17 设计创作，主要内容包括：本发明提供一种基于频率自适应的噪声发电系统及其自适应控制方法,包括：霍尔姆兹腔体、频率自适应装置、压电式声电换能器、机械能-电能转换装置、储能电池组、位移传感器、执行机构等；本发明采用抛物面型的霍尔姆兹腔体设计更有利于对噪声的吸收；同时压电式和静电式声电换能器复用,对噪声作二次回收利用,提高能量转化效率；PID控制器控制腔体的颈口长度可变,使该装置能根据外界输入噪声信号的不同自适应调节颈口长度,实现在200-2000HZ的宽频率范围内均可利用噪声来发电；为延长电池组的使用寿命,采用分布式主动均衡控制器来避免由于电池组内单体电压值的不同对电池的损害,同时还均衡负载、电池组和输入的电能,确保负载电能的正常供应。(The invention provides a noise power generation system based on frequency self-adaptation and a self-adaptation control method thereof, wherein the noise power generation system comprises: the device comprises a Hall Mz cavity, a frequency self-adaption device, a piezoelectric acoustoelectric transducer, a mechanical energy-electric energy conversion device, an energy storage battery pack, a displacement sensor, an actuating mechanism and the like; the invention adopts the design of the paraboloid Hall cavity, which is more favorable for absorbing noise; meanwhile, the piezoelectric type and electrostatic type acoustoelectric transducers are multiplexed, so that the noise is recycled for the second time, and the energy conversion efficiency is improved; the PID controller controls the length of the neck of the cavity to be variable, so that the device can adaptively adjust the length of the neck according to different external input noise signals, and can generate electricity by using noise within a wide frequency range of 200-2000 HZ; in order to prolong the service life of the battery pack, the distributed active balance controller is adopted to avoid the damage to the battery due to the difference of the voltage values of the single batteries in the battery pack, and simultaneously balance the load, the battery pack and the input electric energy, so as to ensure the normal supply of the load electric energy.)

1. A frequency-adaptive based noise power generation system, comprising: the device comprises a Hall Mz cavity, a frequency self-adaption device, a piezoelectric acoustoelectric transducer, a mechanical energy-electric energy conversion device, an energy storage battery pack, a displacement sensor and an actuating mechanism; n piezoelectric acoustic-electric transducers are mounted on the inner surface of the Hall Mz cavity and are electrically connected with the energy storage battery pack after being connected in parallel; a displacement sensor and an actuating mechanism are arranged on a neck opening of the Hall chamber body, a frequency self-adaption device is arranged in the Hall chamber body, and the displacement sensor and the actuating mechanism are respectively and electrically connected with the frequency self-adaption device; one end of the mechanical energy-electric energy conversion device is connected with the Hall-effect cavity, and the other end of the mechanical energy-electric energy conversion device is connected with the energy storage battery pack.

2. The frequency-adaptive-based noise power generation system according to claim 1, wherein the displacement sensor is used for detecting an actual value L of the neck length of the Hall chamber in real time;

the frequency self-adaption device is used for outputting an expected value L of the length of the neck of the Hall chamber through self-adaption control according to the frequency f of external input noise and the actual value L of the length of the neck of the Hall chamber₀；

The actuator is used for executing the operation according to the expected value L₀Real-time toneSaving the length of the neck of the Hall chamber;

the piezoelectric acoustoelectric transducer is used for converting the noise signal into electric energy and transmitting the electric energy to the energy storage battery pack;

the mechanical energy-electric energy conversion device is used for converting mechanical energy generated by the vibration of the Hall Mz cavity into electric energy and transmitting the electric energy to the energy storage battery pack;

the energy storage battery pack is used for storing electric energy.

3. The noise power generation system based on frequency adaptation according to claim 1, wherein the mechanical energy-electric energy conversion device comprises a cylindrical cavity, a movable piston, a spring vibrator, two electrostatic piezoelectric films and an insulating cavity; the bottom end of the Hall Mz cavity arc surface is provided with a port and communicated with the cylindrical cavity, the movable piston is arranged in the cylindrical cavity, the two electrostatic piezoelectric films are arranged in the insulating shell in parallel, the movable electrostatic piezoelectric film is connected with the movable piston, and the electrostatic piezoelectric film fixed in the insulating shell is electrically connected with the energy storage battery pack.

4. The noise power generation system based on frequency adaptation is characterized in that the frequency adaptation device comprises an acoustic-electric conversion device, an A/D conversion module and a microprocessor; one end of the A/D conversion module is electrically connected with the acoustoelectric conversion device, and the other end of the A/D conversion module is electrically connected with the microprocessor;

the sound-electricity conversion device is used for converting the noise signal into an electric signal;

the A/D conversion module is used for converting the electric signal of the analog quantity into a digital quantity and transmitting the digital quantity to the microprocessor;

the microprocessor is used for carrying out Fourier transform on the received digital quantity signal to obtain the resonance frequency corresponding to the maximum energy, and the length of the neck is controlled in a self-adaptive mode through the PID controller to enable the Hall-effect chamber to resonate with noise.

5. The noise power generation system based on frequency adaptation as claimed in claim 1, further comprising a voltage stabilizing circuit, a battery charging control chip, a distributed active balancing controller, a load when the noise power generation system controls the load; the input end of the voltage stabilizing circuit is connected with the electrostatic piezoelectric film, the load is connected with the output end of the voltage stabilizing circuit after being connected with the input end of the battery charging control chip in parallel, and the output end of the distributed active balance controller is connected with the load;

the voltage stabilizing circuit is used for adjusting the received voltage to the working voltage required by the load;

the battery charging control chip is used for controlling the charging state of the energy storage battery pack;

the distributed active equalization controller is used for controlling the discharge state of the energy storage battery pack.

6. The frequency-adaptive noise power generation system according to claim 5, wherein the microprocessor is further configured to generate a control rule for controlling the operation of the battery charging control chip and the distributed active equalization controller, and the control rule is expressed as:

calculating the rated voltage U of the load₀The difference e from the actual operating voltage U, i.e. e ═ U-U₀；

When e is>0、When the battery is charged, the battery charging control chip is controlled to charge the energy storage battery pack;

when e is>0、When the battery is in the open circuit state, the battery charging control chip and the energy storage battery pack are controlled to be in the open circuit state;

when e is<0、When the battery is in the open circuit state, the battery charging control chip and the energy storage battery pack are controlled to be in the open circuit state;

when e is<0、When the energy storage battery pack is in the discharge state, the distributed active equalization controller is controlled to enable the energy storage battery pack to be in the discharge state;

when e is 0,And controlling the distributed active equalization controller to enable the energy storage battery pack to be in an open circuit state.

7. The frequency-adaptive noise power generation system according to claim 5, wherein the microprocessor is further configured to generate an operation mode for controlling the operation of the distributed active equalization controller; the working modes comprise a direct-through mode, a Boost mode, a Buck mode and a fault-tolerant mode;

when in useAnd | U_load-U_BAT|<When epsilon, controlling the distributed active equalization controller to be in a through mode, wherein U_maxFor the maximum cell voltage, U, in the energy storage battery pack_minFor the minimum cell voltage in the energy storage battery pack,for a set voltage threshold, U_loadIs the operating voltage of the load, U_BATThe output voltage of the energy storage battery pack is epsilon, and epsilon is a set threshold value;

when in useAnd U is_load>U_BATWhen the voltage is + epsilon, controlling the distributed active equalization controller to be in a Boost mode;

when in useAnd U is_load<U_BATWhen the voltage is lower than the epsilon, controlling the distributed active equalization controller to be in a Buck voltage reduction mode;

when in useAnd controlling the distributed active equalization controller to be in a fault-tolerant mode.

8. An adaptive control method using the frequency adaptive noise power generation system according to any one of claims 1 to 7, comprising:

step 1: converting the sound signal collected by the sound-electricity conversion device into an electric signal through an A/D conversion module, and converting the electric signal of the analog quantity into a digital quantity;

step 2: calculating the signal frequency value corresponding to the maximum energy in the sound frequency by utilizing Fourier transform as the resonance frequency f formed by the Hall cavity₀；

And step 3: calculating to obtain a resonant frequency f according to a resonant frequency calculation formula of the Hall resonator₀Expected value L of corresponding neck length₀(ii) a The resonant frequency calculation formula of the Hall resonator is as follows:

in the formula, f is the resonance frequency of the cavity, c is the sound velocity, S is the cross-sectional area of the neck, L is the effective length of the neck, and V is the effective volume of the cavity;

and 4, step 4: acquiring an actual value L of the length of the neck of the Hall Mz cavity in real time through a displacement sensor, and transmitting the actual value L to a microprocessor;

and 5: will expect value L₀The difference value with the actual value L is used as the input of a PID controller, and the PID controller outputs the regulating value of the length value in real time;

step 6: and controlling an actuating mechanism to self-adaptively adjust the length of the neck according to the adjusting value of the length value.

Technical Field

The invention belongs to the technical field of noise power generation, and particularly relates to a noise power generation system based on frequency self-adaptation and a self-adaptation control method thereof.

Background

The research on noise power generation devices at home and abroad has broken through a little, and the research is carried out as early as the 17 th century. Swift and Backhaus in the United states of 1999 utilized a standing wave sound field in a "thermo-acoustic Stirling heat engine" to reduce the velocity of gas in a loop; in 2004, Northrop Grumman company and Backhaus cooperated to research a traveling wave thermoacoustic power generation system, a moving coil type linear generator and a traveling wave loop were coupled, and the traveling wave thermoacoustic power generator was manufactured with the function similar to a conventional resonance tube; in 2005, a miniature Hall sound energy generator was developed in the United states, and 0.34uW/cm was obtained under 149dB sound pressure²Electrical power of (a); in 2008, Liu Fei at Florida university has carried out research on Helmholtz resonators, and the maximum recovered electric energy of a novel electric power recovery circuit is utilized to obtain 30mW of energy at 161 dB. The noise is recycled, so that the noise absorption is facilitated, the interference of the noise to daily life is reduced, electric energy is obtained, and the noise-reducing device is energy-saving, environment-friendly and has great practical significance.

At present, the efficiency of the existing noise power generation device is low and is below 10%, and meanwhile, because the energy carried in noise is small and the conversion efficiency is low, the noise power generation device only recovers and generates power aiming at the noise with specific frequency, so that the development of noise power generation is greatly limited.

Disclosure of Invention

Aiming at the problems of low conversion efficiency and power generation in a narrow frequency domain, the invention provides a noise power generation system based on frequency self-adaptation and a self-adaptation control method thereof, and meanwhile, an energy storage battery is managed, so that the service life is prolonged. The invention provides a noise power generation system based on frequency self-adaptation, which comprises: the device comprises a Hall Mz cavity, a frequency self-adaption device, a piezoelectric acoustoelectric transducer, a mechanical energy-electric energy conversion device, an energy storage battery pack, a displacement sensor and an actuating mechanism; n piezoelectric acoustic-electric transducers are mounted on the inner surface of the Hall Mz cavity and are electrically connected with the energy storage battery pack after being connected in parallel; a displacement sensor and an actuating mechanism are arranged on a neck opening of the Hall chamber body, a frequency self-adaption device is arranged in the Hall chamber body, and the displacement sensor and the actuating mechanism are respectively and electrically connected with the frequency self-adaption device; one end of the mechanical energy-electric energy conversion device is connected with the Hall cavity, and the other end of the mechanical energy-electric energy conversion device is connected with the energy storage battery pack;

the displacement sensor is used for detecting the actual value L of the length of the neck of the Hall Mz cavity in real time;

the frequency self-adaption device is used for outputting an expected value L of the length of the neck of the Hall chamber through self-adaption control according to the frequency f of external input noise and the actual value L of the length of the neck of the Hall chamber₀；

The actuator is used for executing the operation according to the expected value L₀Adjusting the length of the Hall's cavity neck in real time;

the piezoelectric acoustoelectric transducer is used for converting the noise signal into electric energy and transmitting the electric energy to the energy storage battery pack;

the mechanical energy-electric energy conversion device is used for converting mechanical energy generated by the vibration of the Hall Mz cavity into electric energy and transmitting the electric energy to the energy storage battery pack;

the energy storage battery pack is used for storing electric energy.

The mechanical energy-electric energy conversion device comprises a cylindrical cavity, a movable piston, a spring vibrator, two electrostatic piezoelectric films and an insulating cavity; the bottom end of the Hall Mz cavity arc surface is provided with a port and communicated with the cylindrical cavity, the movable piston is arranged in the cylindrical cavity, the two electrostatic piezoelectric films are arranged in the insulating shell in parallel, the movable electrostatic piezoelectric film is connected with the movable piston, and the electrostatic piezoelectric film fixed in the insulating shell is electrically connected with the energy storage battery pack.

The frequency self-adaptive device comprises an acoustic-electric conversion device, an A/D conversion module and a microprocessor; one end of the A/D conversion module is electrically connected with the acoustoelectric conversion device, and the other end of the A/D conversion module is electrically connected with the microprocessor;

the sound-electricity conversion device is used for converting the noise signal into an electric signal;

the A/D conversion module is used for converting the electric signal of the analog quantity into a digital quantity and transmitting the digital quantity to the microprocessor;

the microprocessor is used for carrying out Fourier transform on the received digital quantity signal to obtain the resonance frequency corresponding to the maximum energy, and the length of the neck is controlled in a self-adaptive mode through the PID controller to enable the Hall-effect chamber to resonate with noise.

When the noise power generation system controls the load, the system also comprises a voltage stabilizing circuit, a battery charging control chip, a distributed active balance controller and the load; the input end of the voltage stabilizing circuit is connected with the electrostatic piezoelectric film, the load is connected with the output end of the voltage stabilizing circuit after being connected with the input end of the battery charging control chip in parallel, and the output end of the distributed active balance controller is connected with the load;

the voltage stabilizing circuit is used for adjusting the received voltage to the working voltage required by the load;

the battery charging control chip is used for controlling the charging state of the energy storage battery pack;

the distributed active equalization controller is used for controlling the discharge state of the energy storage battery pack.

The microprocessor is also used for generating control rules for controlling the work of the battery charging control chip and the distributed active balance controller, and the control rules are expressed as follows:

calculating the rated voltage U of the load₀The difference e from the actual operating voltage U, i.e. e ═ U-U₀；

When e is>0、When the battery is charged, the battery charging control chip is controlled to charge the energy storage battery pack;

when e is>0、When the battery is in the open circuit state, the battery charging control chip and the energy storage battery pack are controlled to be in the open circuit state;

when e is<0、When the battery is in the open circuit state, the battery charging control chip and the energy storage battery pack are controlled to be in the open circuit state;

when e is<0、When the energy storage battery pack is in the discharge state, the distributed active equalization controller is controlled to enable the energy storage battery pack to be in the discharge state;

when e is 0,And controlling the distributed active equalization controller to enable the energy storage battery pack to be in an open circuit state.

The microprocessor is also used for generating a working mode for controlling the distributed active equalization controller to work; the working modes comprise a direct-through mode, a Boost mode, a Buck mode and a fault-tolerant mode;

when in useAnd | U_load-U_BAT|<When epsilon, controlling the distributed active equalization controller to be in a through mode, wherein U_maxFor the maximum cell voltage, U, in the energy storage battery pack_minFor the minimum cell voltage in the energy storage battery pack,for a set voltage threshold, U_loadIs the operating voltage of the load, U_BATThe output voltage of the energy storage battery pack is epsilon, and epsilon is a set threshold value;

when in useAnd U is_load>U_BATWhen the voltage is + epsilon, controlling the distributed active equalization controller to be in a Boost mode;

when in useAnd U is_load<U_BATWhen the voltage is lower than the epsilon, controlling the distributed active equalization controller to be in a Buck voltage reduction mode;

when in useAnd controlling the distributed active equalization controller to be in a fault-tolerant mode.

An adaptive control method using a frequency-adaptive-based noise power generation system, comprising:

step 1: converting the sound signal collected by the sound-electricity conversion device into an electric signal through an A/D conversion module, and converting the electric signal of the analog quantity into a digital quantity;

step 2: calculating the signal frequency value corresponding to the maximum energy in the sound frequency by utilizing Fourier transform as the resonance frequency f formed by the Hall cavity₀；

And step 3: calculating to obtain a resonant frequency f according to a resonant frequency calculation formula of the Hall resonator₀Expected value L of corresponding neck length₀(ii) a The resonant frequency calculation formula of the Hall resonator is as follows:

in the formula, f is the resonance frequency of the cavity, c is the sound velocity, S is the cross-sectional area of the neck, L is the effective length of the neck, and V is the effective volume of the cavity;

and 4, step 4: acquiring an actual value L of the length of the neck of the Hall Mz cavity in real time through a displacement sensor, and transmitting the actual value L to a microprocessor;

and 5: will expect value L₀The difference value with the actual value L is used as the input of a PID controller, and the PID controller outputs the regulating value of the length value in real time;

step 6: and controlling an actuating mechanism to self-adaptively adjust the length of the neck according to the adjusting value of the length value.

The invention has the beneficial effects that:

the invention provides a noise power generation system based on frequency self-adaptation and a self-adaptation control method thereof, wherein the parabolic Hall-effect cavity is adopted to be more favorable for absorbing noise; meanwhile, the piezoelectric type and electrostatic type acoustoelectric transducers are multiplexed, so that the noise is recycled for the second time, and the energy conversion efficiency is improved; the PID controller controls the length of the neck of the cavity to be variable, so that the device can adaptively adjust the length of the neck according to different external input noise signals, and can generate electricity by using noise within a wide frequency range of 200-2000 HZ; in order to prolong the service life of the battery pack, the distributed active balancing controller is adopted to avoid the damage to the battery due to the difference of the voltage values of the monomers in the battery pack, simultaneously balance the load, the battery pack and the input electric energy, determine the working mode of the distributed active balancing controller according to the size relationship of the load and the input electric energy and ensure the normal supply of the load electric energy; the control rule of the battery charging chip is controlled and generated by an algorithm corresponding to the control rule table, so that the load is maintained to work normally, and the frequent charging and discharging of the battery pack are avoided, thereby prolonging the service life of the battery; and finally, 3.3V, 12V and adjustable voltage values are provided for users to select, and the power consumption requirements of different loads are met.

Drawings

FIG. 1 is a block diagram of a noise power generation system based on frequency adaptation in accordance with the present invention;

FIG. 2 is a flow chart of an adaptive control method of the noise power generation system based on frequency adaptation according to the present invention;

FIG. 3 is an equivalent circuit diagram of piezoelectric acoustoelectric transducers connected in parallel according to the present invention;

FIG. 4 is a schematic diagram of the connection between the battery charging control chip and the energy storage battery according to the present invention;

FIG. 5 is a wiring schematic of a distributed active equalization controller of the present invention;

FIG. 6 is a schematic diagram of the wiring of the circuit of different regulated voltage values in the present invention; (a) a circuit diagram of 12V voltage-stabilizing output, (b) a circuit diagram of 1.2V-35V adjustable voltage-stabilizing output, and (c) a circuit diagram of 3.3V voltage-stabilizing output;

in the figure, 1, a Hall Mz cavity, 2, a frequency self-adaptive device, 3, a piezoelectric acoustoelectric transducer, 4, an energy storage battery pack, 5, a displacement sensor, 6, a cylindrical cavity, 7, a movable piston, 8, a spring vibrator, 9, an electrostatic piezoelectric film I, 10, an electrostatic piezoelectric film II, 11, an insulating cavity, 12, an acoustoelectric conversion device, 13, an A/D conversion module, 14, a microprocessor, 15, a voltage stabilizing circuit, 16, a battery charging control chip, 17, a distributed active balance controller, 18, a load, 19, a lead, 20, a PID controller, 21 and an actuating mechanism.

Detailed Description

The invention is further described with reference to the following figures and specific examples.

As shown in fig. 1, a noise power generation system based on frequency adaptation includes: the device comprises a Hall Mz cavity 1, a frequency self-adaption device 2, a piezoelectric type acoustoelectric transducer 3, a mechanical energy-electric energy conversion device, an energy storage battery pack 4, a displacement sensor 5 and an actuator 21; n piezoelectric acoustic-electric transducers 3 are mounted on the inner surface of the Hall Mz cavity 1, and the N piezoelectric acoustic-electric transducers 3 are connected in parallel and then electrically connected with an energy storage battery pack 4; a displacement sensor 5 and an actuating mechanism 21 are arranged on the neck of the Hall chamber 1, a frequency self-adaption device is arranged in the Hall chamber, and the displacement sensor 5 and the actuating mechanism 21 are respectively and electrically connected with the frequency self-adaption device; one end of the mechanical energy-electric energy conversion device is connected with the Hall chamber 1, and the other end of the mechanical energy-electric energy conversion device is connected with the energy storage battery pack 4.

The displacement sensor is used for detecting the actual value L of the length of the neck of the Hall Mz cavity in real time;

the frequency self-adaption device is used for outputting an expected value L of the length of the neck of the Hall chamber through self-adaption control according to the frequency f of external input noise and the actual value L of the length of the neck of the Hall chamber₀；

The actuator is used for executing the operation according to the expected value L₀Adjusting the length of the Hall's cavity neck in real time;

the piezoelectric acoustoelectric transducer is used for converting the noise signal into electric energy and transmitting the electric energy to the energy storage battery pack;

the mechanical energy-electric energy conversion device is used for converting mechanical energy generated by the vibration of the Hall Mz cavity into electric energy and transmitting the electric energy to the energy storage battery pack;

the energy storage battery pack is used for storing electric energy.

The mechanical energy-electric energy conversion device comprises a cylindrical cavity 6, a movable piston 7, a spring vibrator 8, an electrostatic piezoelectric film I9, an electrostatic piezoelectric film II10 and an insulating cavity 11; the bottom end of the arc surface of the Hall Mz cavity 1 is provided with a port and is communicated with the cylindrical cavity 6, the movable piston 7 is arranged in the cylindrical cavity 6, the electrostatic piezoelectric film I9 and the electrostatic piezoelectric film II10 are arranged in the insulating shell in parallel, the movable electrostatic piezoelectric film I9 is connected with the movable piston 7, and the electrostatic piezoelectric film II10 fixed in the insulating shell is electrically connected with the energy storage battery pack 4.

The frequency self-adaptive device comprises an acoustic-electric conversion device 12, an A/D conversion module 13 and a microprocessor 14; one end of the A/D conversion module 13 is electrically connected with the acoustoelectric conversion device 12, and the other end of the A/D conversion module 13 is electrically connected with the microprocessor 14;

the sound-electricity conversion device is used for converting the noise signal into an electric signal;

the A/D conversion module is used for converting the electric signal of the analog quantity into a digital quantity and transmitting the digital quantity to the microprocessor;

the microprocessor is used for carrying out Fourier transform on the received digital quantity signal to obtain the resonance frequency corresponding to the maximum energy, and the length of the neck is controlled in a self-adaptive mode through the PID controller to enable the Hall-effect chamber to resonate with noise.

When the noise power generation system controls a load, the noise power generation system further comprises a voltage stabilizing circuit 15, a battery charging control chip 16, a distributed active balance controller 17 and a load 18; the input end of the voltage stabilizing circuit 15 is connected with the electrostatic piezoelectric film II10, the input ends of the load 18 and the battery charging control chip 16 are connected in parallel and then connected to the output end of the voltage stabilizing circuit 15, and the output end of the distributed active balance controller 17 is connected with the load 18;

the voltage stabilizing circuit is used for adjusting the received voltage to the working voltage required by the load;

the battery charging control chip is used for controlling the charging state of the energy storage battery pack;

the distributed active equalization controller is used for controlling the discharge state of the energy storage battery pack.

The microprocessor is also used for generating control rules for controlling the work of the battery charging control chip and the distributed active balance controller, and the control rules are expressed as follows:

calculating the rated voltage U of the load₀The difference e from the actual operating voltage U, i.e. e ═ U-U₀；

When e is>0、When the battery is charged, the battery charging control chip is controlled to charge the energy storage battery pack;

when e is>0、When the battery is in the open circuit state, the battery charging control chip and the energy storage battery pack are controlled to be in the open circuit state;

when e is<0、When the battery is in the open circuit state, the battery charging control chip and the energy storage battery pack are controlled to be in the open circuit state;

when e is<0、When the energy storage battery pack is in the discharge state, the distributed active equalization controller is controlled to enable the energy storage battery pack to be in the discharge state;

when e is 0,And controlling the distributed active equalization controller to enable the energy storage battery pack to be in an open circuit state.

The microprocessor is also used for generating a working mode for controlling the distributed active equalization controller to work; the working modes comprise a direct-through mode, a Boost mode, a Buck mode and a fault-tolerant mode;

when in useAnd | U_load-U_BAT|<When epsilon, controlling the distributed active equalization controller to be in a through mode, wherein U_maxFor the maximum cell voltage, U, in the energy storage battery pack_minFor the minimum cell voltage in the energy storage battery pack,for a set voltage threshold, U_loadIs the operating voltage of the load, U_BATThe output voltage of the energy storage battery pack is epsilon, and epsilon is a set threshold value;

when in useAnd U is_load>U_BATWhen the voltage is + epsilon, controlling the distributed active equalization controller to be in a Boost mode;

when in useAnd U is_load<U_BATWhen the voltage is lower than the epsilon, controlling the distributed active equalization controller to be in a Buck voltage reduction mode;

when in useAnd controlling the distributed active equalization controller to be in a fault-tolerant mode.

The specific models of the components in this embodiment are: the piezoelectric acoustoelectric transducer is a PZT-5H piezoelectric ceramic piece, the displacement sensor is GEERT-HM-A2, the electrostatic piezoelectric film is made of polyvinylidene fluoride, the acoustoelectric conversion device is an electret microphone 52DB-9 × 7mm, the A/D conversion module is MAX197, the microprocessor is PDSP16510, the battery charging control chip is CN3717, and the execution mechanism is a direct current motor JGB 37-520. Wherein, the equivalent circuit diagram of the piezoelectric acoustoelectric transducer in parallel is shown in FIG. 3; the wiring schematic diagram of the battery charging control chip and the energy storage battery is shown in fig. 4; a wiring schematic of the distributed active equalization controller is shown in fig. 5; the wiring schematic diagrams of different voltage stabilizing circuits are shown in the figure6 is shown in the specification; the positive electrode of the electrostatic piezoelectric thin-film capacitor is connected with a Vin terminal of the LM2596, the negative electrode of the capacitor is connected with a GND terminal of the LM2596, an output terminal Vout of the LM2596 is connected with a pin VCC No. CN 371715, and a GND of the LM2596 is connected with a pin GND No. 3 of the CN3717 chip; meanwhile, Vout and GND of the voltage stabilizing circuit are directly connected with a load, BAT of the CN3717 chip is respectively connected with the anode and the cathode of the battery pack, the anode and the cathode of the energy storage battery are simultaneously connected with the distributed active balancing controller, the anode and the cathode of the battery pack are correspondingly connected with the anode and the cathode of the BAT, and a load output port and a load port L of the distributed active balancing controller₊、L_-Are directly connected.

The working principle is as follows: displacement sensor places in holmtz cavity neck department, the PZT-5H piezoceramics array is placed to holmtz cavity internal surface, occupy cavity internal surface 90% surface area, external frequency self-adaptation device, can adjust neck length according to the difference of external input noise frequency, the spring oscillator links to each other with electrostatic piezoelectric film, the electric energy that will produce at last is in CN3717 chip storage energy storage battery, adopt hall mtz sympathetic response formula noise collection device to collect the noise, the device comprises parabolic plastic casing, make it collect noise as much as possible, carry out acoustics focus to the sound wave simultaneously, filter the noise, realize the effective utilization of maximize. The focal length is 5cm, the depth is 20cm, and the caliber is 40 cm. An acrylic emulsion coating is applied to the inner surface to increase the reflectivity. Noise is effectively collected and utilized, the large opening of the Hall Mz cavity is connected with the paraboloid type plastic shell, the small opening is used as output to be connected with a subsequent spring mechanical vibrator, and meanwhile, sound energy is amplified, so that the follow-up system can be conveniently provided with as many energy sources as possible, the finally output energy is more, and the effect of improving efficiency is achieved.

When the device is used near a road, relevant research shows that the noise frequency of public transportation is mainly concentrated at about 500HZ, so that the natural frequency of the Hall's cavity in the initial state is set to be 500HZ, the noise input frequency is consistent with the resonance frequency of the cavity, the noise is utilized to the maximum extent, and the utilization rate is improved; when the device is used in other occasions, such as near a mechanical product, the frequency of input noise is changed, a PDSP processor can be installed, firstly, an electret microphone converts acoustic signals into electric signals, when noise is input, the electret film is caused to vibrate to generate displacement, so that the distance between capacitors is changed, the capacitance value is changed, but the contained electric charge is not changed, namely Q is not changed, and Q is CU, so that the voltage change at two ends of the capacitor is caused, the electric signals are output, and then the electric signals are amplified, and the function of sound-electricity conversion is realized; and then, sampling the voltage by using a MAX197 chip, performing Fourier transform (FFT) spectrum analysis based on a PDSP16510 chip, and dynamically adjusting the neck length based on a PID controller to be matched with the input frequency to generate larger energy. This removable arrangement makes it more practical to use the PDSP16510 chip because it involves mathematical operations and consumes power, and most of the time it is not processed by the PDSP16510 processor, but only in certain cases it is calculated using the PDSP 16510.

50 piezoelectric ceramic pieces made of PZT-5H materials are pasted in the Hall Mz cavity, each piezoelectric ceramic piece has the length of 60mm, the width of 30mm, the height of 0.2mm and the density of 7500kg/m³Piezoelectric strain constant of 2.7X 10^-10C/N, modulus of elasticity 7.5X 10¹⁰Pa. Each piezoelectric ceramic piece can be equivalent to a charge source and an interelectrode capacitor which are connected in parallel, when a sound source is input, voltage can be generated on two sides, but because the input of noise is irregular and the time is large and small, a bridge rectifier circuit is added to convert the noise into direct current, then a super capacitor is used for storing electric energy, but because the output current is low, all the piezoelectric ceramics are connected in parallel to improve the output current and enhance the driving capability, and an equivalent circuit diagram is shown in figure 3.

The spring vibrator is placed in the tail part of the Hall Mz resonance cavity, the other end of the vibrator is connected with the polyvinylidene fluoride electrostatic piezoelectric film, so that the spring vibrator vibrates back and forth under the condition of sound energy input, the piezoelectric film moves along with the piezoelectric film, and the function of generating charges is achieved. The electrostatic acoustoelectric transducer using polyvinylidene fluoride has insulating material around the surface layer, one piezoelectric film connected to the mechanical vibrator, the other piezoelectric film inside the surface shell, and two wires led out from the two piezoelectric films for power output.

The two wires for outputting the electric energy are connected with the battery controller, and the battery controller controls the enabling of the CN3717 chip and the working mode of the distributed active equalization controller, so that the whole system is stable and safe, the service life of the battery is prolonged, and the utilization rate of noise is improved.

The connection circuit diagram of CN3713 is shown in fig. 4, and the control charging process of CN3713 chip is as follows:

1) trickle charge mode

When the VCC pin voltage is greater than the low voltage latch threshold 4.2V and greater than the battery voltage, the battery is charged. The battery voltage is less than 75.6% of the overcharge voltage, at which point the trickle charge mode is entered, with a charge current of 19% of the constant current charge. Wherein the overcharge voltage isI_BFor the bias current of the FB pin, the magnitude of the constant current charging is as follows:

2) constant current charging mode

When the voltage of the battery is more than 75.6% of the overcharge voltage, the constant-current charging mode is entered, and the current is

3) Overcharge mode

When the cell voltage approaches the overcharge voltageThen, the overcharge mode is entered, and the charge current is gradually reduced.

4) Float charging mode

When the current in the overcharge mode is gradually reduced to the over-charge ending current, the floating charge mode is entered, and the open-drain output is performedThe transistor in the pin is turned off, the output is in a high-resistance state,the transistor in the pin is conducted, and the output is low level, indicating the floating charge state. Wherein the over-charge termination current is:

5) automatic recharge

When the battery voltage decreases to 82.2% of the overcharge voltage, the trickle charge mode is switched.

In order to prevent the temperature of the battery from being too high, a thermistor with negative temperature coefficient is connected between the TEMP pin of the chip and the ground, and the charging process is interrupted to protect the battery when the temperature is too high. The CN3717 chip is a special integrated circuit for charging management of the lead-acid battery, independently and automatically manages the lead-acid battery, has a wider input voltage range, can input between 7.5V and 28V, can detect the temperature of the battery, and prevents the service life from being shortened due to overhigh temperature of the battery. A thermistor with negative temperature coefficient is connected between the TEMP pin and the ground, when the temperature of the battery is too high, the off-chip P-channel MOS field effect transistor is automatically turned off, the charging circuit is cut off, and the charging is not started until the temperature of the battery returns to a normal range. The voltage range of the TEMP pin is 175 mV-1600 mV, which corresponds to the maximum value and the minimum value of the battery temperature, so that the temperature of the battery during charging can be detected, and the effect of protecting the battery is achieved.

The distributed active balancing controller connects the battery pack with the load, the circuit diagram is shown in fig. 5, the working mode of the distributed active balancing controller is controlled by the battery controller, and there are 4 working modes, which are as follows:

mode 1: straight-through mode

When the difference value between the maximum monomer voltage and the minimum monomer voltage in the battery pack is less than 0.5V, the consistency of the battery pack is better, the battery does not need to be subjected to balanced management, and D₂、D₃Opening, D₁、D₄Closed and the battery is in direct communication with the load on the bus bar.

Mode 2: boost mode

When the load power is larger and the bus voltage required by the load is higher than the battery pack voltage, D is carried out at the moment₂Opening, D₁Closure, D₃、D₄Closing alternately to make it in Boost mode, setting D₃Is alpha, thenThe battery supplies power to the load and raises the voltage of the bus to balance the load.

Mode 3: buck Buck mode

When the load power is small and the bus voltage required by the load is lower than the voltage of the battery pack, D is carried out₄In a closed state, D₃In the off state, D₁、D₂Alternately working to make it in Buck voltage-reducing mode, setting D₁Is alpha, thenThe battery powers the load and reduces the bus voltage.

Mode 4: fault tolerant mode

When the positive and negative fluctuation of the bus voltage is small, in order to avoid the battery pack from being in a frequent charge-discharge state and prolong the service life of the battery, the battery pack is disconnected from the circuit and is not connected to the circuit, and D is carried out at the moment₁、D₂Opening, D₃、D₄Closed, there is no electrical connection of the battery to the bus load.

The distributed active equalization controller divides the system into 5 working modes, and the bus voltage set by a user is set to be U₀，U₀The values can be 3.3V, 5V and 12V, the actual bus voltage obtained by sampling is U, and therefore the voltage error e is equal to U-U₀According to the voltage error e,The value battery controller outputs different control signals, and the specific control correspondence is shown in table 1。

Table 1 control strategy corresponding relation table of distributed active equalization controller

As shown in fig. 2, an adaptive control method using a noise power generation system based on frequency adaptation includes:

step 1: converting the sound signal collected by the sound-electricity conversion device into an electric signal through an A/D conversion module, and converting the electric signal of the analog quantity into a digital quantity;

step 2: calculating the signal frequency value corresponding to the maximum energy in the sound frequency by utilizing Fourier transform as the resonance frequency f formed by the Hall cavity₀；

And step 3: calculating to obtain a resonant frequency f according to a resonant frequency calculation formula of the Hall resonator₀Expected value L of corresponding neck length₀(ii) a The resonant frequency calculation formula of the Hall resonator is as follows:

in the formula, f is the resonance frequency of the cavity, c is the sound velocity, S is the cross-sectional area of the neck, L is the effective length of the neck, and V is the effective volume of the cavity;

and 4, step 4: acquiring an actual value L of the length of the neck of the Hall Mz cavity in real time through a displacement sensor, and transmitting the actual value L to a microprocessor;

and 5: will expect value L₀The difference value with the actual value L is used as the input of a PID controller, and the PID controller outputs the regulating value of the length value in real time; i.e. the difference e (t) is expressed as:

step 6: and controlling an actuating mechanism to self-adaptively adjust the length of the neck according to the adjusting value of the length value.

The invention adopts the paraboloid type Hall chamber as a noise collecting device, has better focusing effect, good directivity, less scattered sound rays and more obvious noise convergence effect. The aperture of the parabolic noise collecting device obtained based on the sound wave focusing method is selected to be 0.4m, and the deep focal ratioFocal length z_FThe depth d is 0.2m and the caliber is 0.4m, which can achieve good noise collection effect.

When a sound source is input, noise can be effectively collected in the parabolic Hall-effect cavity, the reflection effect of the sound source is enhanced by coating the reflection coating of the acrylic acid material on the inner surface, so that the piezoelectric ceramic piece group in the parabolic Hall-effect cavity generates voltage, when an external force F is applied to a single piezoelectric ceramic piece, a potential difference U can be formed at the two poles of the piezoelectric ceramic piece,g is the electric field stress coefficient of the piezoelectric ceramic piece, h is the thickness of the piezoelectric ceramic piece, and S is the effective stress area of the piezoelectric ceramic piece. Let the equivalent interelectrode capacitance of the piezoelectric material be C_inThe resulting charge is therefore: q ═ UC_in，So Q ═ gF epsilon₀Wherein epsilon is the dielectric constant of the piezoelectric ceramic piece₀Is the dielectric constant in vacuum. The piezoelectric ceramic sheet selected here has a length of 60mm, a width of 30mm, a height of 0.2mm, and a density of 7500kg/m³Piezoelectric strain constant of 2.7X 10^-10C/N, modulus of elasticity 7.5X 10¹⁰Pa. All piezo ceramic disc sets were connected in parallel to increase the output current, now analyzed in two parallel connections, as shown in fig. 3. Suppose that the output voltages of the two piezoelectric ceramic plates are U respectively_in1And U_in2Super capacitor C_sTerminal voltage ofWhen in useThen diode D₁₂、D₁₃、D₂₂、D₂₃Conducting; when in useThen diode D₁₁、D₁₄、D₂₂、D₂₃Conducting; when in useTime, diode D₁₂、D₁₃、D₂₁、D₂₄When the three conditions are conducted, the super capacitor is chargedAt this time, 8 diodes are all turned off. The same is true. After all the piezoelectric ceramic plates are connected in parallel, the relation between the voltages can be calculated. Setting the voltage at two ends of the resistor as U_rThe charge of the ith piezoelectric ceramic piece is Q_iEquivalent interelectrode capacitance of C_iThe output current after passing through the rectification circuit is I_iThe method comprises the following steps:the amount of power available can thus be calculated.

According to the calculation formula of the resonance frequency of the Hall Mz cavity,f is the resonant frequency of the cavity, c is the sound velocity, 340m/S is taken, S is the cross-sectional area of the neck, L is the effective length of the neck, and V is the effective volume of the cavity, so that the resonant frequency can be changed by changing the effective length of the neck or the effective volume of the cavity according to a calculation formula, the resonant frequency of the cavity corresponds to the maximum input frequency, and the effect of resonant amplification signals is achieved. The specific realization is that an electret microphone converts an acoustic signal into a voltage signal, and the voltage signal passes through a MAX197 chipLine sampling, the chip supports 8 AD conversion, only a single DC5V power supply is used, the conversion speed is high, the power consumption is low, the power supply of the chip is provided by an LM2596 voltage stabilizing chip, and the circuit connection diagram is shown in figure 6; the converted digital quantity is input to a PDSP16510 chip for FFT operation, the PDSP supports FFT calculation of 1024 points, 256 points and the like in various modes, the calculation speed is high, the calculation result can be calculated within microsecond level, the chip is a special FFT calculation processing chip, the chip is powered by DC5V, and the battery pack is also powered by an LM2596 voltage stabilization chip to obtain the frequency corresponding to the maximum energy component carried in the input; and then the length of the neck is adjusted by a PID controller, wherein the PID calculation formula is as follows:wherein the content of the first and second substances,f is the frequency corresponding to the maximum energy calculated by FFT, c_(t)The neck length is measured by a displacement sensor, so that a closed-loop control system can be formed, and a noise power generation system with adjustable resonance frequency is realized. Wherein the parameter K_pIs a proportional adjustment parameter for rapidly adjusting the length of the neck, a parameter T_IIs an integral adjustment parameter for reducing steady state error, parameter T_DIs a differential adjustment parameter for accelerating the adjustment speed. Considering that the noise input is also changed in real time, f is recalculated every 5 minutes, preventing the maximum frequency corresponding to the input noise from changing, and finally making the resonant frequency of the cavity correspond thereto. The control flow chart is shown in fig. 2.

Secondly, the tail part of the Hall Mz cavity is connected with a spring oscillator, so that the spring oscillator can be driven to move, the other end of the spring oscillator is connected with a piezoelectric film piece made of polyvinylidene fluoride material, the other polyvinylidene fluoride piezoelectric film is fixed at the bottom of the device, the two piezoelectric films form a pair of capacitors, and in the moving process of the spring oscillator, the size of the interelectrode capacitors can be changed, so that charges are generated on the two piezoelectric films; due to the introduction of the spring oscillator, the spring oscillator has a rebound effect when vibrating, so that alternating current can be generated, two leads are led out from the surfaces of the two piezoelectric films to serve as a positive electrode and a negative electrode of energy input, and the energy is input to a subsequent energy storage device.

The electrostatic acoustoelectric transducer can be equivalent to an alternating current power supply and a capacitor which are connected in parallel, when pressure acts on the surface of the electrostatic acoustoelectric transducer, the piezoelectric film sheet can generate corresponding charges, and when the pressure is removed, the charges on the surface of the piezoelectric film sheet can disappear, so that the electrostatic acoustoelectric transducer also needs to be externally connected with a large capacitor for storing the charges. When an external force F acts on the surface of the piezoelectric material, the generated electric charges are: q ═ g₃₃FS_p，g₃₃Is the electric field stress constant, S, of the piezoelectric material_pThe unit of the equivalent stress area of the piezoelectric material is square meter, and the electric field stress coefficient of the polyvinylidene fluoride selected by the invention is as follows: 174 x 10^-3Vom·N^-1So the same external force F will generate more charge. The generated charge forms a voltage of magnitudeUnits of volt, C_pThe invention is a piezoelectric material interelectrode capacitor, and because the invention has the aforementioned voltage input, the energy storage device can be charged, here, the super capacitor is selected as the first-level electricity storage device, the lead storage battery is used as the final energy storage device, but because the noise is irregular input and the time is long, so there is a requirement for the charging equipment, the invention adopts the special charging chip CN3717 to control, the circuit schematic diagram is shown in figure 4, the user can know the working state of the charging equipment by observing the color of the indicator light, when the storage battery is being charged, the red light is on, when the storage battery is fully charged, the green light is on, and when no input, the two indicator lights are not on, the chip can also detect the temperature of the battery, prevent the battery from heating and shorten the service life.

After the energy is stored, when the energy needs to be output to a user for use, the user needs stable voltage output, the invention uses the voltage stabilizing chip LM2596, the voltage stabilizing output of the voltage stabilizing chip LM2596 supports DC3.3V, DC12V, DC1.2-35V adjustable voltage and other voltage stabilizing outputs, the output voltage can be controlled by adjusting the output end, the operation is simple, and the hardware connection diagram is shown in figure 6. Finally, the invention provides different output interfaces to provide different output voltages for users, thereby facilitating the use of different devices of the users.

The device is placed in a general living environment, such as a road side, a market and the like, and the noise is mainly concentrated on about 500HZ according to related research, so that the length of the neck can be manually adjusted to be 20cm without connecting a frequency self-adaptive device, and the frequency self-adaptive device relates to the operation of a chip, so that the power generation efficiency is improved, and the frequency self-adaptive device can be disconnected under the condition so as to reduce the loss of self electric energy. After noise is input, the PZT-5H piezoelectric sheets connected in parallel are influenced by the noise to generate charges, the electrostatic film can also generate the charges under the reciprocating motion of the spring vibrator, all the charges are sent to CN3717 through a lead to charge the battery, and the charging and discharging sizes of the battery are controlled to protect the battery; LM2596 is the steady voltage output chip, and the user can adjust the output steady voltage value manually according to own needs.

Near KTV and large-scale machinery factories, because the concentrated noise frequency at this moment is different from the ordinary time, the self-adaptive frequency device can be connected, the input noise converts the sound signal into a voltage signal through an electret microphone, the voltage A/D is converted and sampled by MAX197, the digital quantity is output and then is sent to PDSP16510 for FFT calculation, the frequency at this moment is obtained, and finally the neck length of the Hall's cavity is automatically adjusted through PID, so that the purpose of maximizing the generated energy is achieved.

Compared with the existing device, the device is characterized in that the following gain effects are achieved:

1. the natural frequency of the Hall Mz cavity can be dynamically adjusted, and the Hall Mz cavity is adaptive to the external environment.

2. The distributed active balance controller balances the battery pack, the load and the input electric energy, prevents a large single voltage difference value when the battery pack works, and prolongs the service life of the battery.

3. The control rule of the battery charging chip generates a control signal by an algorithm, so that the load requirement is met, and the frequent charging and discharging of the battery are avoided.

4. The MAX197 sampling and PDSP16150 are used for FFT operation, and the FFT operation is combined with a PID controller, and the FFT operation is used when necessary, so that the self energy consumption is reduced.

5. The parabolic collection device is adopted, so that noise is effectively collected and amplified.

6. The CN3713 chip is adopted to control the charging of the lead storage battery, so that the electricity storage efficiency is improved, and the control is accurate. When the voltage is output, the voltage passes through the voltage stabilizing chip LM2596, so that the output voltage is stable, and the voltage grades are diversified.

7. The electrostatic acoustoelectric transducer is made of polyvinylidene fluoride material, so that the power generation efficiency is improved.

8. The piezoelectric type and the electrostatic type acoustoelectric transducer are multiplexed, and the power generation efficiency is improved.