CN113504407A - Spherical sensing device for sound intensity detection of adjacent area of ultra-high voltage transmission line and implementation method - Google Patents
Spherical sensing device for sound intensity detection of adjacent area of ultra-high voltage transmission line and implementation method Download PDFInfo
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Abstract
The invention relates to a sound intensity detection device for an adjacent area of an ultra-high voltage transmission line and an implementation method. In order to adapt to the measuring environment of high potential and strong electric field, the device is designed into a spherical structure with good voltage-sharing performance and can be applied to the extra-high voltage direct current environment of +/-1100 kV. The device can synchronously acquire up to 14 paths of sound pressure signals at a sound source, solve sound intensity components on three orthogonal axes in real time according to a sound intensity algorithm provided by the invention, and send the sound intensity signals to a local safety end through a wireless transmission unit. The invention arranges 14 sound pressure sensors in a pairwise matching manner in 7 specific directions of the spherical structure so as to obtain sound intensity values of 7 different directions, and then establishes a redundant linear mapping model based on a special position relation among the directions, so that a three-dimensional sound intensity vector of a sound source position can be accurately detected.
Description
Technical Field
The invention belongs to the technical field of extra-high voltage power transmission of a power system, and particularly relates to a spherical sound intensity detection device for an adjacent area of an extra-high voltage power transmission line and an implementation method thereof.
Background
With the continuous improvement of the voltage grade of the ultra-high voltage transmission line, the electromagnetic environmental problem generated by corona discharge becomes one of the decisive factors of the line design, wherein the audible noise caused by corona is widely concerned at present because people can feel the audible noise in person. The characteristics, the generation mechanism, the propagation rule and the ground effect of audible noise generated by corona discharge of the extra-high voltage line are researched, the level of the audible noise can be accurately predicted and even controlled, and the method has important significance for building a power transmission line meeting the environmental protection requirement.
The audible noise can be diffused and attenuated in the process of propagation, and can be reflected on the surface of obstacles such as the earth, buildings and the like. The sound pressure level of the noise is typically measured at a height of about 1.5m from the ground, and is also mixed with ambient noise and difficult to filter. Thus, audible noise detected near the ground is distorted to varying degrees. In contrast, detecting noise at a sound source in the vicinity of the transmission line can avoid much interference, which is helpful for understanding the intrinsic characteristics and rules of the noise, and is undoubtedly a better research method. In addition, the sound pressure level is a physical quantity representing the intensity of the sound source radiation noise, but the sound pressure level is a scalar quantity, and the referential of the measured data in different environments is poor. The sound intensity is a vector, can better reflect the energy, flow and propagation state of a sound source, and has better expressive force on audible noise. At present, sound intensity detection is widely applied to the aspects of equipment fault diagnosis and quality control, sound power measurement, sound source positioning, environmental noise monitoring and the like.
The traditional method for measuring the audible noise sound pressure level on the ground cannot meet the research requirement on the mechanism characteristics of the audible noise sound source, but due to the complex electromagnetic environment of the ultra-high voltage transmission line, a detection method applied to the noise source of the ultra-high voltage true transmission line does not appear in the existing research. In fact, the adjacent area of the ultra-high voltage transmission line is the sound source position of the corona discharge audible noise, the information of the noise source can be directly detected, and accordingly the time-frequency domain characteristics and the change rule of the audible noise source can be directly researched and analyzed. The sound intensity is measured in the adjacent area of the ultra-high voltage transmission line, which is helpful for deeply understanding the mechanism and the rule of a sound source, deepens the scientific understanding of the phenomenon and guides people to take targeted measures to solve the problem.
Disclosure of Invention
In order to overcome the problems in the prior art, the invention discloses a spherical sensing device for detecting the sound intensity of the adjacent area of an ultra-high voltage transmission line and an implementation method thereof, wherein the spherical sensing device comprises a sound intensity algorithm based on the device framework. The invention aims to parallelly acquire multi-path sound pressure at the high-voltage end of an ultra-high voltage transmission line and calculate a three-dimensional sound intensity vector, and then transmit detected sound intensity data to an upper computer through a wireless transmission module.
In order to achieve the purpose, the invention specifically adopts the following technical scheme: a can be used in the sphere sensing apparatus and implement method that the ultra-high voltage transmission line is adjacent to regional sound intensity to detect, the sensing apparatus includes the sphere fixed structure, 14 way acoustic pressure sensor, high-speed data acquisition module, signal processing unit, wireless transmission unit 1 and power supply unit; the implementation method is that according to the arrangement rule of 14 paths of sensor arrays on the spherical structure, the sound intensity values in specific different linear directions are calculated through a sound intensity algorithm, and then a redundant linear mapping model is established based on the special position relation among all the directions so as to obtain the sound intensity vector at the spherical center.
The spherical fixed structure is arranged in the adjacent area of the ultra-high voltage transmission line, and other modules of the detection device are wrapped inside the spherical fixed structure, so that the equipment can be protected to normally work in the open air environment. Because the detection device is positioned in a complex electromagnetic environment of an extra-high voltage adjacent area, the point discharge can be effectively avoided by selecting a spherical structure with the best insulation and voltage-sharing effects. The sphere radius design needs to consider the size of the adjacent space of the power transmission line and the volume of other internal modules, and the requirement of sound intensity detection is met. The spherical surface is polished smoothly, the surface is covered by a metal net, the sound intensity detection is not influenced while the corona field intensity of the surface of the device is improved, and the safe and reliable work of the detection device in a +/-1100 kV extra-high voltage environment is ensured.
The 14-path sound pressure sensor is arranged at 14 specific points of a spherical structure: a space rectangular coordinate system is established at the sphere center, 6 intersection points of the coordinate axis and the sphere and the central points of the sphere segments corresponding to 8 quadrants are selected, and 14 point positions in 7 diameter directions are obtained. The 14 sound pressure sensors with the same characteristics are equally divided into 7 groups and are arranged at 14 points on the spherical surface along the 7 diameter directions, as shown in fig. 2. 7 supports are specially designed along the 7 diameter directions, each group of sensors are fixed at two ends of each support in a back-mounted mode, and the centers of the vibrating diaphragms of the sensors are symmetrical about the center of a sphere and point to an outside sound field. The sound pressure sensor uses an electret condenser microphone, and the electret condenser microphone has the advantages of a common condenser microphone: wide frequency range, flat frequency response, small sensitivity change and high long-term stability. Meanwhile, the defects of the traditional condenser microphone are avoided, 200V polarization voltage does not need to be added, and the design of a power supply unit can be simplified.
The high-speed data acquisition module comprises a conditioning circuit and an AD sampling unit. The conditioning circuit adopts a preamplifier to convert weak high-impedance output voltage acquired by the sound pressure sensor into low-impedance voltage, and amplifies the voltage to a standard bipolar 10V range; the AD sampling unit uses a 16-bit high-precision 16-channel collector, and the conversion rate is required to reach 200kSPS (kilovolt pulse sequence standard) so as to complete high-precision high-speed analog-to-digital conversion.
The signal processing unit receives data of the high-speed data acquisition module by using the FPGA chip, then performs digital signal processing according to the sound intensity algorithm provided by the invention, and sends the sound intensity vector to the safety end through the wireless transmission module. The FPGA realizes two functions of control and operation: the FPGA-based wireless transmission unit is used as a control unit to enable the AD sampling unit to work, set sampling frequency and a data output form, and simultaneously send sound intensity data and a control instruction to the wireless transmission unit; as the arithmetic unit, FPGA can utilize hardware multiplier on the chip and integrated function block IP core to finish the parallel digital signal processing algorithm such as FFT, FIR, etc. with high efficiency, and has outstanding advantages in time and power consumption, and can better meet the realization requirement of the sound intensity algorithm.
The wireless transmission unit provides a transmission distance of not less than 100m by using a ZigBee transmission technology, and can receive instructions and data of the FPGA and send the detected sound intensity to other wireless transmission modules at a far safety end. The wireless transmission unit is arranged on the spherical fixed structure and points to the ground below or on the side of the power transmission line, then the ground area capable of stably receiving signals is determined through tests, the ZigBee receiving device is arranged in the ground area, and finally the detected sound intensity is transmitted to the upper computer for monitoring and analyzing the sound intensity information of the sound source.
The power supply unit adopts a large-capacity battery, and ensures that each module of the sound intensity detection device can supply power for a long time. Meanwhile, circuits such as voltage boosting, voltage reducing, voltage stabilizing, filtering and coupling need to be built, power interference is suppressed, power supply quality is improved, and a required standard power interface is provided for each module.
The realization method is that according to the arrangement characteristics of the 14-path sound pressure sensor, the diameter of a sphere is used as a standard distance, and the sound intensity of the midpoint position in a specific direction is solved according to the sound pressure measured by two paired microphones in the direction. Thus, the sound intensity values of 7 different directions can be obtained, and the sound intensity of each direction can be regarded as the projection of the actual sound intensity vector in the direction. A linear mapping model is established based on the special position relation of the projection in each direction, and a linear equation system containing 3 unknown quantities can be obtained, as shown in the following:
in the formula Ix、Iy、IzThe component of the sound intensity vector of the position to be measured under the three-dimensional rectangular coordinate system; i isEF、IAB、ICD、IMR、ILQ、IPH、INGAre sound intensity measurements for 7 specific directions as shown in fig. 5.
Because the number of equations is greater than the number of unknowns, the above equation set generally does not have a mathematically rigorous exact solution, and only an approximate solution in engineering can be found using the measured data. The traditional approximate solution is to select partial equations with the same number as the unknowns and solve the mathematical solution, but the measurement data cannot be fully utilized, and the solved solution may have large errors.
To minimize the error of the above equation set, the linear equation set is described in the form of a matrix
Therein is provided with
According to the matrix theory, the pseudo inverse of the coefficient matrix Q is obtained
Let the optimal solution be
The optimal solution is equal to the pseudo-inverse P of the coefficient matrix multiplied by the vector
Is provided with
Three-dimensional vector
The optimal solution of the sound intensity vector of the position to be measured is obtained.
The invention has the following technical effects:
on one hand, the spherical structure provided by the invention can be flexibly arranged on the inner side or the outer side of the power transmission line, the electric field intensity on the surface of the device is reduced due to the complete symmetry of the sphere, and the voltage-sharing and electromagnetic protection effects are better; due to the good anti-interference characteristic, the spherical structure can use a wireless transmission technology, the problems of erection and protection of a wired transmission line are avoided, and the audible noise intensity can be safely and reliably detected and transmitted at an extra-high voltage environment sound source. On the other hand, the sensor with the spherical structure is more flexible in layout, a plurality of typical positions can be selected to redundantly measure sound pressure signals, and then the sound intensity vector of the point to be measured is calculated according to the sound intensity algorithm provided by the patent by utilizing a plurality of directional data, so that the random error in measurement is reduced, and the accuracy of the sound intensity detection result is improved.
Drawings
FIG. 1 is a schematic diagram of the system architecture of the present invention;
FIG. 2 is a schematic diagram of the 14-way acoustic pressure sensor arrangement of the present invention (only a portion of the sensor is shown);
FIG. 3 is a block diagram of a signal processing unit;
FIG. 4 is a schematic diagram of a unidirectional matching sensor;
FIG. 5 is a sensor array layout point map of the present invention;
the system comprises a spherical fixed structure 1, a sound pressure sensor 2-14 paths, a high-speed data acquisition module 3, a signal processing unit 4, a wireless transmission unit 5, a power supply unit 1, 6, a wireless transmission unit 7, a host computer 8, an AD sampling unit 9, an FIFO data cache module 10, a Flash memory 11 and a sound intensity vector operation module 12.
Detailed Description
The invention is described in detail below with reference to the accompanying drawings.
The invention relates to a spherical sound intensity detection device for an adjacent area of an ultra-high voltage transmission line and an implementation method. As shown in figure 1, the invention comprises a 1-spherical fixed structure, 2-14 sound pressure sensors, a 3-high speed data acquisition module, a 4-signal processing unit, a 5-wireless transmission unit 1, 6-power supply unit, and a 7-wireless transmission unit 2, 8-upper computer.
The spherical sensing device is arranged in the adjacent area of the ultra-high voltage transmission line, and the working principle is as follows: the 14 paths of sound pressure sensors with the same characteristics collect 7 groups of sound pressure information near a sound source and output bipolar high-impedance voltage signals (the specific range is related to the sensitivity of the sound pressure sensors); the high-speed data acquisition module converts a high-impedance signal into a low impedance signal by using a preamplifier, amplifies the low impedance signal into a voltage signal within a standard range of +/-10V, and synchronously acquires 14 paths of sound pressure signals by using a 16-bit-precision AD sampling unit; the signal processing unit uses the FPGA to obtain unidirectional sound intensity by converting sound pressure data paired in 7 directions according to a sound intensity algorithm provided by the invention, and then obtains a sound intensity vector at a sound source by converting the sound intensities in 7 different directions; the wireless transmission unit transmits the sound intensity to the upper computer of the safety end, and real-time detection of the sound intensity of the sound source can be achieved.
The spherical fixed structure is used for fixing and protecting each module of the device, and ensures the safety detection of the sound intensity of the ultra-high voltage transmission line sound source. The smooth spherical structure of polishing can reduce the intensity of the surface distortion electric field of the device, improve the voltage-sharing performance and have better electromagnetic protection effect. The radius of the sphere is reasonably designed through software simulation to change the surface curvature of the device, so that the sharp corona discharge is avoided, and the device is prevented from being broken down by a strong electric field. And finally, carrying out an ultraviolet discharge test in a +/-1100 kV high-potential environment, determining that the surface and the interior of the device are not punctured and corona, and ensuring that the device is not damaged or damaged after voltage reduction and grounding. Otherwise, structural parameters are simulated and designed again, the machining process is improved, and the installation position is adjusted to ensure that the sound intensity detection device stably and reliably works in the extra-high voltage environment.
Fig. 2 shows a schematic diagram of a 14-way sound pressure sensor arrangement. The spherical structure is divided into 8 quadrants by using 3 rectangular coordinate axes with the sphere center as the origin, and 6 intersection points of the 3 coordinate axes and the sphere and the central points of the 8 sphere quadrants are determined. According to the symmetry of the sphere, 14 intersection points are respectively located on the straight line where 7 diameters are located. Every two sound pressure sensors with the same characteristics are divided into 7 groups, and the two groups are respectively arranged on a spherical surface along the 7 linear directions. The sensor is fixed on 7 supports in the linear direction, a back-mounted structure is adopted, the vibrating diaphragm is flush with the spherical surface, and the sound pressure of each point position near the sound source is detected through the metal mesh for protecting the spherical surface. Preferably, the Sound pressure sensor is a 40AZ model 1/2 inch electret condenser microphone from GRAS Sound & Vibration, Denmark. The measuring frequency band of the microphone is 0.5 Hz-20 kHz, and the range of the frequency band of audible noise is met; the sound pressure measurement range is 14 dB-148 dB, and the high sensitivity of 50mV/Pa is realized. The microphone has small size, the diameter of the diaphragm is 13.2mm, the height of the diaphragm is 16.3mm, the microphone can be conveniently arranged on the fixed support, and the requirement of high-precision sound pressure measurement is completely met.
The high-speed data acquisition module comprises a conditioning circuit and an AD sampling unit. For the selected type 40AZ microphone described above, the sensitivity thereof was calibrated in a standard anechoic chamber, and then the sound pressure range at the noise source was estimated, and the output voltage of the microphone was calculated from the sensitivity. The conditioning circuit adopts a preamplifier to amplify the output signal of the microphone to be within a standard bipolar +/-10V range while carrying out impedance conversion, and then carries out analog-to-digital conversion on a standard voltage signal through an AD sampling unit. Preferably, the AD sampling unit is an AD7616 chip. The AD7616 is a 16-bit data acquisition system, a double-channel 16-bit charge redistribution SAR analog-to-digital converter is arranged in the system, double-channel synchronous sampling of 16 channels is supported, and the data throughput rate of each channel reaches 1 MSPS. The chip can be used for synchronously sampling two paths of sound pressure signals which are mutually matched in the same direction, so that sound pressure acquisition in 7 directions is respectively completed.
The signal processing unit uses an FPGA as a control unit and an operation execution unit. Preferably, the FPGA selects an Altera corporation Cyclone series EP4CE10F17C8 chip. On the basis of basic FPGA architecture resources, the chip series device is added with a clock management unit PLL, an embedded memory unit M9K and a hardware multiplier. In use, the M9K module may be configured as a single port, dual port RAM, and FIFO buffer or ROM to facilitate storage of various data during operation. Using multipliers, digital signal processing algorithms like FFT, FIR etc. can be designed that achieve a more efficient parallel structure. Therefore, the chip can better meet the requirements of data storage, multipath parallel FFT operation and the like in signal processing.
The FPGA chip is used as a control unit and can control the AD sampling unit, the FIFO data cache module, the Flash memory, the sound intensity vector operation unit module and the wireless transmission unit 1 to work in a coordinated and ordered mode. And (3) using the input and output, logic control and data operation of the Verilog HDL design program, then completing functional simulation and time sequence simulation, and finally downloading the configured logic circuit into a chip and performing experimental verification. Preferably, the Flash memory uses AN M29W640GT7AN6F chip, which can be powered by 3.3V and has 64 mbytes of storage space, and can store data of a larger size.
Fig. 4 is a block diagram of the signal processing unit. The FIFO data buffer module is configured by an M9K module on an FPGA chip, and digital signals with 16-bit precision output by the AD sampling unit are temporarily stored in the module to prevent data from being blocked or lost. The Flash memory is used for storing data in a large scale and comprises 14 paths of original sound pressure data with 16-bit precision and sound intensity vector data obtained through operation. When the cache module overflows, transferring the data into a Flash memory; the sound intensity vector operation module performs signal processing by utilizing abundant computing resources on the FPGA chip, such as a hardware multiplier, an IP core of a comprehensive function block and the like, converts acquired sound pressure into sound intensity according to a sound intensity algorithm provided by the patent, and then sends the sound intensity to a safety end in real time through a wireless transmission unit.
The wireless transmission unit adopts a ZigBee module. The ZigBee wireless communication technology is a bidirectional wireless communication network technology with low speed, low power consumption, low complexity and low cost, can improve the standby time by dozens of times compared with Bluetooth or WiFi transmission, simultaneously reduces the requirements on a communication controller, and has the longest transmission distance of not less than 100 m. The Zigbee module comprises a sending part and a receiving part which are respectively arranged in the sound intensity detection device at the high-voltage end and the upper computer receiving module at the safety end, is used for communication of sound intensity detection results, and can meet the requirements of design and application.
The array sensors are arranged in 7 specific directions according to the spherical structure, and the sound intensity detection algorithm provided by the patent comprises two steps: firstly, unidirectional sound intensity conversion is carried out, namely a sound intensity value in the direction is obtained through two sound pressure sensors matched in pairs on a specific single straight line; and then, three-dimensional sound intensity vector conversion is carried out, namely an equation set is established according to a special geometric mapping relation in 7 straight line directions, the solving error is minimized through the pseudo-inverse of a coefficient matrix, and the optimal solution of the sound intensity vector is obtained through calculation.
The sensor that arranges on the spherical device measures the sound pressure signal, therefore this patent proposes the conversion of unilateral sound intensity, turns into the sound intensity with two sound pressures that match the sensor and measure on the collinear. Assuming that the diameter of the spherical device is d, the length is taken as the standard distance between two matched sensors, and a back-to-back arrangement is adopted, as shown in fig. 4, wherein reference points 1 and 2 are two adjacent points of the point 0 to be measured, and the distances from the two adjacent points to the point 0 are equal. The sound intensity at the central point 0 can be obtained by the sound pressure approximation at the two points 1 and 2.
According to the motion equation of an ideal streaming medium, the relationship between the particle vibration velocity and the sound pressure is
The sound pressure can be directly measured by the sound pressure sensor, but the sound pressure gradient in equation (1) cannot be directly measured. According to the finite difference principle, the sound pressure gradient along the x direction at a certain point 0 in the sound field can be approximately estimated by the sound pressure value of two adjacent reference points in the direction, and the vibration velocity of the particle 0 in the x direction is
The sound pressure at 0 point can be approximately expressed as the average of the sound pressures at two reference points, i.e., p ═ p (p)1+p2) 2, the projection component of the transient intensity vector of the 0 point in the x direction can be expressed as
The two acoustic pressure sensors should have the same frequency response characteristics and should be perfectly matched in phase and amplitude. Phase and amplitude mismatches directly affect the sound intensity measurement according to equation (3). Therefore, two matched sensors in a single linear direction must be phase and amplitude calibrated before measurement, with appropriate compensation being taken as necessary to control measurement errors.
The above formula gives a calculation method of instantaneous sound intensity, but generally, we need to calculate the average sound intensity in a certain period of time or analyze the distribution characteristics of the sound intensity in each frequency in the period of time, so this patent gives a theoretical derivation of the sound intensity frequency distribution.
First, a cross-correlation function between the sound pressure p and the particle vibration velocity u is calculated
The relation between the average sound intensity and the cross-correlation function in one period is
The cross-correlation function is called as cross-spectral density function through Fourier transformation, and then inverse Fourier transformation is carried out on the cross-correlation function to obtain an original function which can be expressed as
Combinations (5) and (6) of
Equation (7) shows the cross-spectral density function S of pressure and vibration velocitypu(ω) is a distribution function of the mean sound intensity in the frequency domain. The cross-spectral density function defined in equation (6) is bilateral and meaningful for both positive and negative frequencies. Here, taking the single-sided cross-spectral density function Gpu(ω) having a relationship with a bilateral cross-spectral density function of
The distribution function of the sound intensity at frequency domain point ω in the frequency domain can be expressed as
I(ω)＝Spu(ω)+Spu(-ω)＝Re[Gpu(ω)] (9)
Setting Fourier transformation of P (t) and U (t) as P (omega) and U (omega), according to linear and integral characteristics of Fourier transformation, the method has
According to the Veno-Cinzhou theorem, the cross-spectrum of two signals is the product of the Fourier transform of one signal and the conjugate of the Fourier transform of the other signal, having
Substituting the formula (10) into the formula (11) to obtain
In the formula G22、G11The single-sided self-spectral density function, G, of the sound pressure at point 2 and point 1, respectively12Is a single-sided cross-spectral density function of the sound pressure at point 1 and point 2, Im representing the imaginary part.
Substituting equation (12) into (9) can obtain the frequency distribution function of the average sound intensity:
equation (13) shows that with two matched sound pressure sensors at a distance d, the average sound intensity at its center point at this normalized distance can be obtained. Therefore, the sound intensity values in 7 specific directions can be obtained by this method.
The three-dimensional sound intensity vector conversion method is to establish an equation set according to specific geometric relations of sound intensity values in 7 directions to solve the sound intensity vector at a point to be measured. The sensor geometry layout model is shown in fig. 5. Intersection points A, B, C, D, E, F of the 3 coordinate axes and the spherical surface are determined, and three sets of sound pressure sensors are arranged on the spherical surface in the diameter direction. Then, the central points of the ball segments corresponding to the 8 hanging limits are determined, and four groups of sensors are arranged along the diameter direction.
Recording the sound intensity components of the body center 0 point in the x, y and z orthogonal directions as Ix、Iy、IzWhen the unit vectors in the three orthogonal directions are I, j, and k, respectively, the sound intensity Io at the O point is Ixi+Iyj+Izk. The sound intensity value measured in each direction is actually IOThe projection in this direction can also be regarded as the sound intensity components I of three orthogonal directionsx、Iy、IzProjection in this direction. Taking the body diameter MR direction as an example, the cosine values of the included angles between MR and the x-axis, y-axis and z-axis are respectively found from the mathematical relationship:
IOacoustic intensity value I in MR directionMRIs equal to Ixi+Iyj+Izk the sum of the projections in this direction:
similarly, projection equations for other diametric directions can be listed, establishing the following equation set:
in the formula Ix、Iy、IzThe component of the sound intensity vector of the body center O point at the position to be detected in the three-dimensional rectangular coordinate system; i isEF、IAB、ICD、IMR、ILQ、IPH、INGIs a measure of the sound intensity in 7 particular directions.
Since the sound intensity in a single direction is approximately obtained according to the finite difference principle, the left and right ends of the above equation set are approximately equal rather than strictly equal. The equation set comprises 3 unknowns and 7 equations, belongs to an overdetermined linear equation set, and cannot be solved accurately. In order to minimize the error of the equation set solution, the patent provides a sound intensity vector conversion method based on the matrix theory. The system of equations (16) is first written as a matrix of a system of linear equations:
therein is provided with
For the above linear homogeneous system of equations without solution, let
Is a solution that minimizes the error of the equation set, i.e., it can be a norm
A minimum value is reached. According to the matrix theory, it can be known that
Where P is the pseudo-inverse of the coefficient matrix Q. Is calculated to
The optimal solution of the system of linear equations under this condition is then
According to the formula (18), the optimal solution of the sound intensity vector at the point O can be obtained:
the embodiments of the present invention have been described in detail and illustrated in the accompanying drawings by the applicant of the present invention, but it should be understood by those skilled in the art that the above embodiments are only the preferred embodiments of the present invention, and the detailed description is only for the purpose of helping the reader to better understand the spirit of the present invention, and not for limiting the scope of the present invention, and on the contrary, any improvement or modification made based on the spirit of the present invention should fall within the scope of the present invention.
Claims (8)
1. A spherical sensing device for detecting the sound intensity of the adjacent area of an ultra-high voltage transmission line and a realization method thereof are characterized in that:
the spherical sensing device comprises a spherical fixed structure, a 14-path sound pressure sensor, a high-speed data acquisition module, a signal processing unit, a wireless transmission unit 1 and a power supply unit; the spherical fixing structure is arranged in the area adjacent to the split conductor, is used for fixing other modules, and has electromagnetic shielding, voltage-sharing and insulating effects; the 14 paths of sound pressure sensors are arranged at 14 specific positions of the spherical fixed structure to form a sound pressure sensor array so as to measure sound pressures in 7 different directions; the high-speed data acquisition module processes and converts analog signals output by the sensor array into digital signals; the signal processing unit uses an FPGA (field programmable gate array), and according to the sound intensity algorithm provided by the invention, the 14 paths of sound pressure signals are resolved into sound intensity values of the point to be measured in three orthogonal directions, so as to obtain a three-dimensional sound intensity vector of the position to be measured; the wireless transmission unit 1 transmits the measurement result to a wireless transmission unit 2 of a remote safety end, and then uploads the measurement result to an upper computer; the power supply unit adopts a high-capacity battery and supplies power to other modules of the detection device through a voltage conversion and voltage stabilizing circuit.
The implementation method comprises the steps of calculating specific sound intensity values in different linear directions according to the arrangement rule and the matching mode of the sensor array on the spherical structure and the sound intensity algorithm, and then establishing a redundant linear mapping model based on the special position relation among all the directions to obtain the sound intensity vector at the center of the sphere.
2. The spherical fixation structure of claim 1, wherein:
the spherical fixing structure is used for installing and fixing the sound intensity detection device, the radius of the sphere needs to consider the size of the space adjacent to the power transmission line and the volume of other modules inside the power transmission line, meanwhile, the spherical surface is polished smoothly, the surface of the spherical surface is covered by a metal net, the structure is guaranteed to have good electromagnetic shielding and voltage-sharing characteristics, corona discharge does not occur in a strong electric field environment, and sound intensity measurement is not affected.
3. The acoustic pressure sensor of claim 1, wherein:
the sound pressure sensor adopts an electret condenser microphone, 200V polarization voltage does not need to be added, and the design of a power supply unit can be simplified.
4. The high speed data acquisition module of claim 1, wherein:
the high-speed data acquisition module comprises a conditioning circuit and an AD sampling unit. The conditioning circuit converts weak high-impedance voltage acquired by the sound pressure sensor into low-impedance output voltage through a preamplifier, and amplifies the voltage to a standard bipolar 10V range; the AD sampling unit uses 14 channels to collect standard voltage signals in parallel.
5. The 14 specific locations according to claim 1, wherein:
the 14 specific positions are formed by establishing a space rectangular coordinate system at the sphere center of the spherical fixed structure, generating 6 intersection points between 3 coordinate axes and the spherical surface, dividing the spherical surface into 8 symmetrical segment areas, and then taking the center point of each segment to obtain 14 specific points on the spherical surface. From the symmetry of the sphere, 14 points can be considered as the intersection of 7 diameters in specific directions with the sphere. Every two sound pressure sensors with the same characteristics are divided into 7 groups, and the two groups are respectively arranged at 14 specific points of a spherical surface along the 7 straight lines, as shown in fig. 2.
6. The wireless transmission unit 1 according to claim 1, characterized in that:
the wireless transmission unit 1 uses a ZigBee transmission technology, provides a transmission distance of not less than 100m, can send the detected sound intensity vector to the wireless transmission unit 2 of the far safety end, and then uploads the detected sound intensity vector to the upper computer.
7. The sound intensity algorithm of claim 1, wherein:
the sound intensity algorithm is used for solving the sound intensity vector at the center of the sphere, according to the specific arrangement mode of the sensors provided by the invention, the sound intensities in 7 specific directions are firstly calculated, then a linear equation set is established according to the linear mapping relation between the 7 specific directions and the coordinate axes, and the optimal solution of the sound intensity vector under the arrangement mode is obtained. The over-determined system of linear equations is described as
In the formula Ix、Iy、IzThe component of the sound intensity vector at the sphere center under the three-dimensional rectangular coordinate system; i isEF、IAB、ICD、IMR、ILQ、IPH、INGIs a measure of the sound intensity in 7 particular directions.
8. The optimal solution of claim 7, wherein:
the optimal solution minimizes the error of the linear equation set, and describes the linear equation set as a matrix form
Therein is provided with
According to matrix theory, the optimal solution is equal to the pseudo-inverse of the coefficient matrix multiplied by the vector
Find the optimal solution as
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100061186A1 (en) * | 2006-11-30 | 2010-03-11 | Cardinale Ciccotti Giuseppe | method for localizing remote devices, using acoustical and electromagnetic waves |
| CN103196546A (en) * | 2013-01-24 | 2013-07-10 | 中国船舶重工集团公司第七一五研究所 | Acoustic parameter near field measuring method of underwater sound sensor |
| CN106680376A (en) * | 2017-01-23 | 2017-05-17 | 华南理工大学 | Sound insulation measurement system and measurement method based on three-dimensional sound intensity array |
| US20170314385A1 (en) * | 2016-04-28 | 2017-11-02 | Schlumberger Technology Corporation | System and methodology for acoustic measurement driven geo-steering |
| CN108051800A (en) * | 2017-12-13 | 2018-05-18 | 贵州航天计量测试技术研究所 | The room noise source localization method of the idle sound intensity is reconstructed based on spherical surface near field acoustic holography |
| CN111596262A (en) * | 2020-05-07 | 2020-08-28 | 武汉大学 | Vector hydrophone and multi-target direction estimation method based on vector hydrophone |
| CN112683386A (en) * | 2020-12-03 | 2021-04-20 | 中国船舶重工集团公司第七一五研究所 | Integral piezoelectric vibration velocity vector hydrophone |
-
2021
- 2021-07-14 CN CN202110792696.6A patent/CN113504407B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100061186A1 (en) * | 2006-11-30 | 2010-03-11 | Cardinale Ciccotti Giuseppe | method for localizing remote devices, using acoustical and electromagnetic waves |
| CN103196546A (en) * | 2013-01-24 | 2013-07-10 | 中国船舶重工集团公司第七一五研究所 | Acoustic parameter near field measuring method of underwater sound sensor |
| US20170314385A1 (en) * | 2016-04-28 | 2017-11-02 | Schlumberger Technology Corporation | System and methodology for acoustic measurement driven geo-steering |
| CN106680376A (en) * | 2017-01-23 | 2017-05-17 | 华南理工大学 | Sound insulation measurement system and measurement method based on three-dimensional sound intensity array |
| CN108051800A (en) * | 2017-12-13 | 2018-05-18 | 贵州航天计量测试技术研究所 | The room noise source localization method of the idle sound intensity is reconstructed based on spherical surface near field acoustic holography |
| CN111596262A (en) * | 2020-05-07 | 2020-08-28 | 武汉大学 | Vector hydrophone and multi-target direction estimation method based on vector hydrophone |
| CN112683386A (en) * | 2020-12-03 | 2021-04-20 | 中国船舶重工集团公司第七一五研究所 | Integral piezoelectric vibration velocity vector hydrophone |
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