阅读说明：本技术 基于图像融合技术的多参数电磁层析成像装置及方法 (Multi-parameter electromagnetic tomography device and method based on image fusion technology ) 是由 张文彪 刘瑶瑶 郑晓媛 方黄峰 于 2019-12-17 设计创作，主要内容包括：本发明公开了一种基于图像融合技术的多参数电磁层析成像装置及方法。该装置由线圈阵列、磁阻传感器阵列、模拟开关、信号发生器、功率放大器、磁感应强度测量模块、互感测量模块和计算机组成；一方面,线圈阵列通过信号发生器和功率放大器提供的正弦激励产生交变磁场,磁阻传感器阵列测量对应位置的磁场感应强度,实现磁导率分布的图像重建；另一方面,互感测量模块经模拟开关依次获取各线圈激励下激励线圈与其余线圈之间的互感值,实现电导率分布的图像重建；基于图像融合算法将两种信息的图像重建结果融合,可以同时获得电导率和磁导率分布的成像结果。本发明可提供一种针对电导率和磁导率介质同时成像的多参数电磁层析成像方法。(The invention discloses a multi-parameter electromagnetic tomography device and method based on an image fusion technology. The device consists of a coil array, a magnetic resistance sensor array, an analog switch, a signal generator, a power amplifier, a magnetic induction intensity measuring module, a mutual inductance measuring module and a computer; on one hand, the coil array generates an alternating magnetic field through sinusoidal excitation provided by the signal generator and the power amplifier, and the magnetic resistance sensor array measures the magnetic field induction intensity of the corresponding position to realize the image reconstruction of magnetic conductivity distribution; on the other hand, the mutual inductance measuring module sequentially obtains mutual inductance values between the exciting coil and the rest of coils under the excitation of each coil through the analog switch, and the image reconstruction of the conductivity distribution is realized; the image reconstruction results of the two kinds of information are fused based on an image fusion algorithm, and the imaging results of the conductivity and the magnetic conductivity distribution can be obtained simultaneously. The invention can provide a multi-parameter electromagnetic tomography method for simultaneously imaging the conductivity and permeability media.)

1. The multi-parameter electromagnetic tomography device based on the image fusion technology is characterized by comprising a coil array, a magnetic resistance sensor array, an analog switch, a signal generator, a power amplifier, a magnetic induction intensity measuring module, a mutual inductance measuring module and a computer.

2. The multi-parameter electromagnetic tomography apparatus based on image fusion technology as claimed in claim 1, wherein the coil/magnetic resistance sensor array is assembled by a plurality of groups of coils and magnetic resistance sensors to form an excitation/detection array, and the excitation/detection array is uniformly arranged around the circular imaging area at equal angles. Wherein the number and arrangement of the excitation/detection arrays are adjusted accordingly according to the size of the imaging area.

3. The excitation/detection array of claim 2, wherein the excitation/detection array is assembled from coils and magnetoresistive sensors, wherein the coils are multi-turn coils wound with pure copper wires, and parameters such as inner diameter, outer diameter, thickness and number of turns of the multi-turn coils can be adjusted accordingly according to actual needs.

4. The multi-parameter electromagnetic tomography apparatus based on image fusion technique as claimed in claim 1, wherein the signal generator is connected to a power amplifier, and the power amplifier is connected to an analog switch to drive the coil. The magnetic induction intensity measuring module is connected with the magnetic resistance sensor array, obtains sensor output signals of different positions and uploads the sensor output signals to the computer for signal demodulation and magnetic conductivity distribution reconstruction.

5. The signal generator, power amplifier and analog switch of claim 4, wherein the signal generator generates a sinusoidal drive signal of a specific frequency, which is amplified by the power amplifier and used to drive the drive coil. The function of the analog switch comprises two parts: under the action of control signals, the sequential switching of coil excitation is realized, and an alternating magnetic field is generated by an excitation coil; and the analog switch is connected with a plurality of coils to realize the sequential switching of the coils to the measurement of the mutual inductance value.

6. The multi-parameter electromagnetic tomography apparatus based on image fusion technology as claimed in claim 1, wherein the mutual inductance measurement module is connected with an analog switch, and the mutual inductance values of different excitation/detection coil pairs can be obtained by the mutual inductance measurement module through the switching function of the analog switch and uploaded to the computer for the reconstruction of the conductivity distribution.

7. The multi-parameter electromagnetic tomography method based on the image fusion technology is characterized in that mutual inductance information of different excitation/detection coil pairs is obtained by a mutual inductance measuring module, and conductivity distribution in an imaging area is obtained by combining a corresponding image reconstruction algorithm; and magnetic induction intensity information of different positions around the imaging area is obtained by utilizing a magnetic induction intensity measuring module, and magnetic permeability distribution in the imaging area is obtained by combining a corresponding image reconstruction algorithm. According to the obtained image reconstruction result, a pair of images representing the distribution conditions of the conductivity and the permeability in the reconstruction area is obtained by combining a pixel-level pyramid decomposition image fusion method, and then multi-parameter electromagnetic tomography is realized.

Technical Field

The invention belongs to the field of process parameter detection, and particularly relates to a multi-parameter electromagnetic tomography device and method based on an image fusion technology.

Technical Field

Multiphase flow is widely existed in various industrial processes, such as the production and processing fields of power industrial production, crude oil extraction, food processing, medicine manufacturing and the like, so that the realization of multiphase flow parameter detection is very important for ensuring the safety of industrial production, improving the production efficiency and optimizing the industrial production process. For a complex multiphase flow system, the process tomography is an ideal means for realizing real-time online imaging of the flow state of the multiphase flow.

In the field of multiphase flow parameter detection, the process tomography technology is widely applied due to the excellent characteristics of low cost, simple sensor structure, non-invasive measurement and the like. Nevertheless, most tomographic techniques applied to multi-phase flow detection tend to image only one electromagnetic property. Furthermore, for multiphase flows with complex flow conditions, they usually contain both conductive and permeable substances. The existing tomography method can not image the object effectively.

The invention provides a multi-parameter electromagnetic tomography device and method based on an image fusion technology.

The invention has the beneficial effects that: 1) the device and the method have simple sensor structure and low cost, and are a non-invasive measurement method; 2) the electromagnetic tomography method can realize simultaneous imaging of two electromagnetic properties of conductivity and magnetic conductivity, and has good imaging effect.

Disclosure of Invention

The invention aims to provide a multi-parameter electromagnetic tomography device and method based on an image fusion technology. The device consists of a coil array, a magnetic resistance sensor array, an analog switch, a signal generator, a power amplifier, a magnetic induction intensity measuring module, a mutual inductance measuring module and a computer;

the coil arrays are uniformly arranged around the circular imaging area at equal angles. The coil array is connected with a signal generator through an analog switch and a power amplifier so as to apply sinusoidal excitation signals to corresponding coils. Each coil is formed by winding a plurality of turns of copper wires, the size of each coil is 38mm in outer diameter, 20mm in inner diameter and 5mm in thickness, the number of turns is about 160 turns, and the specific size of each coil is determined according to the size of a circular imaging area.

The magnetic resistance sensor array is uniformly arranged on the axis of each coil according to the size of the coil array, and is tightly attached to the edge of the circular imaging area for measuring the alternating magnetic field. Each magnetoresistive sensor is made into a PCB by a Tunneling Magnetoresistive (TMR) chip and corresponding signal conditioning circuits such as amplification and filtering.

The excitation/detection arrays are uniformly assembled around the circular imaging area by a plurality of groups of coils and magneto-resistive sensors in equal angles, wherein the number and the arrangement mode of the excitation/detection arrays are correspondingly adjusted according to the size of the imaging area.

The analog switch includes two functions: on one hand, the device is connected with an excitation signal (a signal generator and a power amplifier) for coil excitation to be sequentially switched, and on the other hand, the device is connected with a mutual inductance measuring module to realize sequential measurement of mutual inductance values between the excitation coil and other coils under different coil excitations.

The signal generator may generate various common excitation signals including sinusoidal signals, square wave signals, triangular wave signals, and the like. The power amplifying circuit is connected with a power resistor in series and then applies alternating current excitation to the exciting coil.

The power amplifier amplifies the power of the small signal generated by the signal generator for coil excitation.

The magnetic induction intensity measuring module is connected with the magneto-resistance sensor array, and the output signals of the magneto-resistance sensor array are obtained and used for signal demodulation and image reconstruction

The mutual inductance measuring module adopts a four-terminal wiring mode to measure the mutual inductance between two coils.

The multi-parameter electromagnetic tomography device and method based on the image fusion technology, provided by the invention, have the advantages of simple structure, low cost, convenience in installation and simplicity and convenience in operation, can be used for imaging the conductivity and the magnetic conductivity at the same time, and are novel and effective.

Drawings

FIG. 1 is a schematic structural diagram of a multi-parameter electromagnetic tomography device based on an image fusion technique.

In the figure: 1. an array of magnetoresistive sensors; 2. a coil array; 3. an object having magnetic permeability; 4. an object having an electrical conductivity; 5, simulating a switch; 6. a mutual inductance measurement module; 7. a signal generator; 8. a power amplifier; 9. a magnetic induction intensity measuring module; 10. computer with a memory card

Fig. 2 is a schematic diagram of a coil/magnetoresistive sensor.

In the figure: 1. a magnetoresistive sensor; 2. coil

Fig. 3 is a schematic view of image fusion.

Detailed Description

The invention provides a multi-parameter electromagnetic tomography device and method based on an image fusion technology. The multi-parameter electromagnetic tomography device based on the image fusion technology is composed of a coil array, a magnetic resistance sensor array, an analog switch, a signal generator, a power amplifier, a magnetic induction intensity measuring module, a mutual inductance measuring module and a computer; the simultaneous imaging of the conductivity and the magnetic conductivity can be realized; the invention is described below with reference to the accompanying drawings:

fig. 1 is a schematic diagram of a schematic structure of a multi-parameter electromagnetic tomography device based on an image fusion technology. In the figure, a magnetoresistive sensor array 1 and an excitation coil array 2 are assembled together, as shown in a schematic diagram of a coil/magnetoresistive sensor in fig. 2, a magnetoresistive sensor PCB is placed on the axis of a coil, so that the sensitive axis of a TMR chip is parallel to the normal direction of a circular imaging area at a corresponding measuring point, and the z-axis direction is the sensitive axis direction of TMR. The object 3 with magnetic permeability and the object 4 with electrical conductivity are placed in a circular imaging area, which is constituted by a cylinder made of acrylic tubes. The signal generator 7 is connected to the analog switch 5 through the power amplifier 8, the analog switch 5 is connected with the exciting coil array 1, and the exciting coils are sequentially driven to generate an alternating magnetic field. The output of the magnetic resistance sensor array 1 is collected by the magnetic induction intensity measuring module 9 and uploaded to a computer for signal demodulation and image reconstruction, and a reconstructed image with magnetic conductivity mu distribution is obtained.

The excitation/detection array is formed by assembling a coil array and a magnetoresistive sensor array, and the excitation/detection array is uniformly distributed around a circular imaging area at equal angles, as shown in figure 1. The size of each coil, the number of the magnetic resistance sensors and the arrangement mode need to be adjusted correspondingly according to the detection precision requirement and the size of the circular imaging area.

In fig. 1, the mutual inductance measurement module is connected to the coil array via an analog switch. When each coil is excited, the rest coils are used as detection coils, and the mutual inductance value of the excitation/detection coil pair can be obtained by utilizing the mutual inductance measuring module through the switching function of the analog switch. Then switching to the next coil excitation and repeating the previous operation. After all the required mutual inductance values are obtained, a reconstructed image of the conductivity σ distribution can be obtained in combination with a corresponding image reconstruction algorithm.

Fig. 3 is a schematic diagram of image fusion, and an image representing the distribution of the electrical conductivity and the magnetic conductivity at the same time can be obtained by fusing reconstructed images of the electrical conductivity and the magnetic conductivity through an image fusion algorithm based on pyramidal decomposition.