Environmental sound energy focusing system

Abstract

An environment sound energy focusing system comprises an energy picking device, a sound gathering cover and a charging circuit, the energy picking device adopts PVDF piezoelectric films to construct an energy picking array and can pick up sound wave signals in the frequency band of 20 Hz to 20 kHz, the inner surface of the sound gathering cover is in a parabola shape, environment sound waves can be focused to the energy picking array, and the capture efficiency and energy density of the sound waves are remarkably improved; and the charging circuit is responsible for receiving the electric energy converted by the energy collecting device, and rectifying and storing the electric energy. According to the utility model, through optimizing the pickup, conversion and focusing processes of sound energy, the system significantly improves the power supply efficiency, and provides stable and reliable energy support for power-free and low-power-consumption equipment. Meanwhile, the system is not only suitable for typical environments such as transformer substations, high mountains and oceans, but also can effectively work in windless cloudy and rainy weather, and the application range of the self-energy-taking technology is further widened.

Description

Technical Field

[0001] This invention relates to an environmental sound energy focusing system, and in particular to a system that uses piezoelectric materials to convert environmental sound energy into electrical energy. It is suitable for applications with no power supply and low power consumption, such as remote sensors and environmental monitoring equipment. Background Technology

[0002] Nature has many renewable energy sources, such as wind, solar, and sound. Wind and solar power generation has been widely used, but the energy utilization rate of various sound energy and noise in nature is very low. Many people are researching this, but the low energy density makes sound power generation inefficient and difficult to put into practice.

[0003] Ambient sound (noise) is a renewable form of environmental energy, and its main characteristics include physical parameters such as frequency, amplitude (sound pressure level), and spectral distribution. Analyzing and investigating the characteristics of ambient sound can provide important basis for the design of sound energy conversion systems, and at the same time reveal the potential for utilizing sound energy in different application scenarios.

[0004] In self-harvesting energy detection systems, low power efficiency is a significant technical challenge restricting their practical application. Existing energy harvesting technologies (such as solar and wind power) are difficult to operate effectively in specific environments (such as windless, cloudy, or rainy days). Ambient sound, as a widely existing form of energy, has great potential for utilization. However, existing sound energy harvesting systems suffer from low efficiency and insufficient output power, making it difficult to meet practical application requirements. Summary of the Invention

[0005] The purpose of this invention is to provide an environmental sound energy focusing system that improves power efficiency by optimizing the sound energy pickup and conversion process, thereby meeting the power supply needs of special occasions.

[0006] The technical solution of this utility model is as follows:

[0007] An environmental sound energy focusing system, characterized in that it includes:

[0008] An energy harvesting device is used to capture ambient sound energy and convert it into electrical energy. The energy harvesting device uses PVDF piezoelectric film as the energy harvesting material and is connected in electrical parallel to form an energy harvesting array.

[0009] The sound-focusing hood has a parabolic cross-section on its inner surface, which is used to focus ambient sound waves onto the location of the energy-harvesting array to enhance the sound wave capture efficiency and energy density.

[0010] The charging circuit is electrically connected to the energy pickup device and is used to receive the electrical energy converted by the energy pickup device, and to rectify and store it.

[0011] The PVDF piezoelectric film has a wide frequency response characteristic, covering the mid-to-low frequency sound range, and can effectively pick up sound wave signals in the 20Hz to 20kHz frequency band.

[0012] The energy pickup array includes:

[0013] The outer ring of PVDF film is uniformly distributed and tilted outwards to receive lateral and axial sound waves;

[0014] The inner ring PVDF film is placed vertically and intersects with the outer ring PVDF film to compensate for lateral sound wave energy loss.

[0015] The top PVDF film, parallel to the mouth of the acoustic hood, is used to receive axial sound waves.

[0016] The sound-focusing dome has an aperture of 391.92 mm, an inner surface focal length of 40 mm, an outer surface focal length of 43 mm, and a focal depth of 200 mm, and is used for focusing vertically or nearly vertically incident sound waves.

[0017] The charging circuit includes multiple sub-units. Each sub-unit contains a capacitor connected in parallel across the two ends of the PVDF piezoelectric film and a bridge rectifier circuit, which converts the AC power generated by the PVDF piezoelectric film into DC power, and then inputs it into the energy storage circuit after filtering by the bus capacitor.

[0018] The energy storage circuit is used to store rectified and filtered DC power.

[0019] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0020] By optimizing the process of sound energy pickup, conversion, and focusing, power efficiency has been significantly improved, providing stable and reliable energy support for applications requiring no power supply or low power consumption.

[0021] It is not only suitable for typical environments such as substations, high mountains, and oceans, but can also work effectively in windless and rainy weather, thus broadening the application scope of self-powered technology.

[0022] Generating electricity using ambient sound energy eliminates the need for traditional energy sources, aligning with the current trend of environmental protection and energy conservation. Attached Figure Description

[0023] Figure 1 PVDF array

[0024] Figure 2 3D structural diagram of the sound-concentrating cover

[0025] Figure 3 Fixed buckle

[0026] Figure 4 Energy pickup device

[0027] Figure 5 Energy harvesting device structure from different perspectives

[0028] Figure 6 System overall diagram Detailed Implementation

[0029] The present invention will be further explained below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the scope of protection of the present invention.

[0030] Energy pickup device design:

[0031] LDTM-028K type PVDF piezoelectric film was selected as the energy-harvesting material, which possesses excellent piezoelectric properties and wideband response characteristics. Multiple PVDF film elements were connected in parallel electrically to form an energy-harvesting array. The specific number and arrangement of the array can be adjusted according to the actual application scenario and requirements.

[0032] In an environment with noise frequencies close to the natural frequency of the PVDF film (approximately 550 Hz) and a sound intensity of 100 dB, the discharge power of a single PVDF film is only about 0.01 mW, significantly lower than the expected 1 mW. This power gap indicates that the energy pickup efficiency of a single PVDF film may be limited in certain application scenarios. Therefore, to improve the output power of the energy pickup module, the system performance can be optimized by constructing a PVDF film array. Multiple PVDF film elements are used, and their output power is superimposed through electrical parallel connection. Since each PVDF film responds independently to the vibration signal of the sound field, increasing the number of units in the array can effectively improve the total output power. The array configuration increases the sound-receiving area, enabling the sensor system to capture a wider range of sound wave energy, further improving the overall output performance.

[0033] At the focal point of the parabolic acoustic diaphragm, sound waves radiate from all directions, forming a wide distribution of sound sources. At this point, using a ring array maximizes the sound wave capture efficiency, allowing the array to receive sound signals from all directions. Therefore, to optimize the sound wave capture effect, we designed a uniquely structured ring support with an outer octagonal ring and an inner square ring. This support can accommodate 16 PVDF thin-film sensors. Eight PVDF films are evenly distributed on the outer ring, each tilted outwards at 20 degrees, receiving both lateral and axial sound waves. Four PVDF films are distributed on the inner ring, placed vertically without tilt, and staggered with the outer ring films, primarily receiving lateral sound waves to compensate for energy loss due to the tilt of the outer ring films. Four PVDF films are distributed on the top surface, parallel to the diaphragm's opening, receiving axial sound waves. This structure maximizes the capture of sound wave energy from all directions near the focal point of the parabolic acoustic diaphragm, significantly improving the effective area and overall performance of sound wave reception. This design improves acquisition accuracy while optimizing spatial layout, enabling the array to provide more stable signal reception in multiple directions, such as... Figure 1 As shown.

[0034] Sound enclosure design:

[0035] The parabolic acoustic condenser utilizes the focusing effect of a parabola to concentrate sound waves into a region near the focal point, achieving sound energy concentration and focusing. The inner surface of the condenser has a parabolic cross-section with a specific focal length and aperture. Through precise calculation and design, it is ensured that sound waves can be effectively focused into the region near the focal point. The condenser is made of rigid materials to ensure its structural stability and durability. Simultaneously, rigid bent steel spokes are designed as a support structure to precisely fix the PVDF array near the focal point of the condenser.

[0036] Figure 2 The mechanical structure of the acoustic condenser is shown. The condenser has a diameter of 391.92 mm, and its inner surface cross-section is a parabolic shape with a focal length of 40 mm, while the outer surface cross-section is also parabolic with a focal length of 43 mm. The focal point of the inner surface is located 200 mm from the plane of the rim, referred to as the focal depth. In this design, vertically (or nearly vertically) incident sound waves are focused onto the area near the focal point, thus concentrating and focusing the sound energy. This structure allows the sound waves to form a significant energy accumulation in the focal region, improving the sound wave capture efficiency and sensing effect. To ensure the precise fixing of the PVDF array near the focal point of the condenser, rigid bent steel spokes are designed as a support structure, such as... Figure 3As shown. This structure not only provides sufficient rigidity but also ensures the stability and accuracy of the installation. Furthermore, we have specially designed matching fixing clips on the PVDF array base and the edge of the acoustic enclosure, which not only facilitates installation and adjustment but also effectively prevents displacement caused by vibration or external forces, ensuring the reliability and consistency of signal acquisition. The assembled energy pickup device is as follows. Figure 4 As shown, a support base is designed for the energy pickup device. The elliptical base has openings that allow for free adjustment of the orientation of the sound-collecting dome, aligning it with the sound source and improving energy pickup efficiency. The complete device is shown below. Figure 5 As shown.

[0037] Circuit design:

[0038] The charging circuit consists of multiple sub-units and a bus capacitor. Each sub-unit includes a capacitor connected in parallel across the piezoelectric film and a bridge rectifier circuit. Through filtering and rectification, the captured sound energy is converted into DC power output. An energy storage circuit stores the DC power output from the charging circuit, providing continuous power to low-power devices. The specific type and capacity of the energy storage circuit can be selected based on the actual application scenario and requirements.

[0039] Workflow:

[0040] Deploy the energy pickup device and the sound-collecting hood in the target environment;

[0041] The ambient sound waves are focused onto the energy-harvesting array by the sound-focusing cover;

[0042] The energy-collecting array is used to collect the focused acoustic wave energy and convert it into electrical energy.

[0043] The converted electrical energy is rectified and stored through the charging circuit.

[0044] Example:

[0045] like Figure 6 As shown, the sound-collecting cover is adjusted to face the sound source, allowing the sound waves to be concentrated on the PVDF film. The sound-collecting cover is connected to the acquisition and energy storage circuits via wires. The acquisition circuit collects the charge generated by the PVDF film and transfers it to the energy storage circuit, which then stores this charge in a capacitor. A low-power indicator light is connected to the output of the charging circuit to monitor the energy collection effect of the device in real time; an LED display module is connected to the output of the voltage regulator circuit to display the output effect of the energy storage circuit.

[0046] During the experiment, a sound source was applied to the acoustic enclosure and the PVDF film. As the sound intensity changed, the brightness of the low-power indicator light at the charging circuit output changed accordingly; the capacitor in the energy storage circuit gradually stored charge. After a certain period of energy storage, turning on the capacitor's output switch revealed that the LED display module was lit, its brightness gradually decreasing until it went out, indicating that the stored charge in the capacitor had been completely released. The experimental setup visually demonstrated the process and working principle of converting sound energy into electrical energy and storing it.

Claims

1. An ambient sound energy focusing system, characterized by, include: An energy harvesting device is used to capture ambient sound energy and convert it into electrical energy. The energy harvesting device uses PVDF piezoelectric film as the energy harvesting material and is connected in electrical parallel to form an energy harvesting array. The energy pickup array includes: The outer ring of PVDF film is uniformly distributed and tilted outwards to receive lateral and axial sound waves; The inner ring PVDF film is placed vertically and intersects with the outer ring PVDF film to compensate for lateral sound wave energy loss. The top PVDF film, parallel to the mouth of the sound-gathering hood, is used to receive axial sound waves; The sound-focusing hood has a parabolic cross-section on its inner surface, which is used to focus ambient sound waves onto the location of the energy-harvesting array to enhance the sound wave capture efficiency and energy density. The charging circuit, electrically connected to the energy pickup device, includes multiple sub-units. Each sub-unit contains a capacitor connected in parallel across the PVDF piezoelectric film and a bridge rectifier circuit, used to convert the AC power generated by the PVDF piezoelectric film into DC power, which is then filtered by the bus capacitor and input into the energy storage circuit.

2. The ambient sound energy focusing system of claim 1, wherein, The PVDF piezoelectric film has a wide frequency response characteristic, covering the mid-to-low frequency sound range, and can effectively pick up sound wave signals in the 20Hz to 20kHz frequency band.

3. The ambient sound energy focusing system of claim 1 or 2, wherein, The sound focusing hood has a diameter of 391.92 mm, an inner surface focal length of 40 mm, an outer surface focal length of 43 mm, and a focal depth of 200 mm, and is used for focusing sound waves incident vertically or nearly vertically.

4. The ambient sound energy focusing system of claim 1, wherein, The energy storage circuit is used to store rectified and filtered DC power.

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