Magnetic flux leakage detection anti-interference method based on coding excitation and synchronous decoding and related device
By using a method of encoded excitation and synchronous decoding, the problems of electromagnetic interference and channel crosstalk in magnetic flux leakage detection were solved, achieving high signal-to-noise ratio defect detection and improving the reliability and accuracy of detection.
Patent Information
- Application Number
- CN202511755104.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-26
- Publication Date
- 2026-01-09
AI Technical Summary
Traditional magnetic flux leakage detection methods face problems such as electromagnetic interference, channel crosstalk, and instability of excitation sources in industrial settings, resulting in poor reliability and repeatability of detection results. Existing anti-interference technologies also have limited effectiveness.
The method of coded excitation and synchronous decoding is adopted. The excitation signal is encoded by pseudo-random sequence to construct coded characteristic magnetic field. The mixed signal is obtained by magnetic sensor array and synchronous decoding is performed by cross-correlation operation or matched filtering to actively distinguish defect signals from noise.
It significantly improves the signal-to-noise ratio, enhances the anti-interference capability of magnetic flux leakage detection, ensures high reliability and high accuracy of detection, and is suitable for complex working conditions.
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Figure CN121298880A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of nondestructive testing, and particularly relates to a magnetic flux leakage detection anti-interference method based on coded excitation and synchronous decoding and a related device. BACKGROUND
[0002] Magnetic flux leakage detection is one of the widely used nondestructive testing methods for ferromagnetic component defect detection. The basic principle of magnetic flux leakage detection is to magnetize the test piece to saturation or near saturation state through an excitation device. When there is a defect in the component, the magnetic force line will be distorted at the defect, and part of the magnetic flux will leak to the outside space of the component to form a magnetic flux leakage field. By using Hall, AMR (Anisotropic Magnetoresistance), GMR (Giant Magnetoresistance) or TMR (Tunnel Magnetoresistance) magnetic sensors to detect the magnetic flux leakage field, the position and size of the defect can be inversely calculated.
[0003] However, the traditional magnetic flux leakage detection method faces severe challenges in actual industrial applications. First, the industrial site is full of various electromagnetic interference sources, such as motors, frequency converters and power grid harmonics, etc. These noises will seriously pollute the weak magnetic flux leakage signal. Second, when a multi-channel sensor array is used for rapid scanning, the cross-talk problem between channels is prominent. In addition, the fluctuation of the background magnetic field and the instability of the excitation source itself will also reduce the reliability and repeatability of the detection results.
[0004] In order to suppress interference, the existing technology usually adopts passive means such as hardware shielding, analog filtering and differential amplification. For example, a band-pass filter and a power frequency trap are designed in the signal processing circuit to filter out noise of specific frequency. However, these methods have limited effect when facing noise whose frequency band overlaps with that of the defect signal or non-stationary random interference, and may also cause distortion of useful signals.
[0005] Therefore, there is an urgent need for an active anti-interference technology that can essentially distinguish defect signals from environmental noise to improve the performance of magnetic flux leakage detection under complex working conditions. SUMMARY
[0006] The purpose of the present application is to provide a magnetic flux leakage detection anti-interference method based on coded excitation and synchronous decoding and a related device, which solves the problem of poor anti-interference effect of the prior art.
[0007] In order to achieve the above purpose, the present application adopts the following technical solutions: In a first aspect, the present application provides a magnetic flux leakage detection anti-interference method based on coded excitation and synchronous decoding, comprising the following steps: acquire an excitation signal; encode the excitation signal to obtain a digital coded sequence; modulate the digital coded sequence to a carrier wave with a set frequency to obtain a coded excitation signal; power amplify the coded excitation signal to obtain a power-amplified coded excitation signal; magnetize a test piece based on the power-amplified coded excitation signal to construct a magnetic field with coded characteristics; acquire a mixed signal on the surface of the test piece, the mixed signal including a defect leakage magnetic signal and environmental noise; synchronously decode the mixed signal on the surface of the test piece and the coded excitation signal to obtain a defect characteristic signal related to the coded excitation signal; analyze the defect characteristic signal to obtain a defect detection result of the test piece.
[0008] The application further improves that the encoding of the excitation signal to obtain a digital coded sequence is specifically encoding the excitation signal by a pseudo-random sequence to obtain a digital coded sequence.
[0009] The application further improves that the digital coded sequence is one of a pseudo-random sequence, a linear frequency modulation signal or a multi-frequency orthogonal signal.
[0010] The application further improves that the pseudo-random sequence is an m-sequence or a Gold sequence.
[0011] The application further improves that the acquisition of the mixed signal on the surface of the test piece is specifically acquiring the mixed signal on the surface of the test piece by a magnetic sensor array.
[0012] The application further improves that the synchronous decoding is cross-correlation operation or matched filtering.
[0013] The application further improves that before the synchronous decoding of the mixed signal on the surface of the test piece and the coded excitation signal to obtain a defect characteristic signal related to the coded excitation signal, the mixed signal on the surface of the test piece and the environmental noise are amplified and filtered for pretreatment.
[0014] In the second aspect, the application provides a magnetic leakage detection anti-interference system based on coded excitation and synchronous decoding, including: a data acquisition module for acquiring an excitation signal; an encoding module for encoding the excitation signal to obtain a digital coded sequence; a modulation module for modulating the digital coded sequence to a carrier wave with a set frequency to obtain a coded excitation signal; A power amplification module is configured to perform power amplification on the coded excitation signal to obtain a power-amplified coded excitation signal. A magnetization module is configured to magnetize the test piece based on the power-amplified coded excitation signal to construct a magnetic field with coded characteristics. A mixed signal acquisition module is configured to acquire a mixed signal on the surface of the test piece, the mixed signal including a defect leakage magnetic signal and environmental noise. A decoding module is configured to synchronously decode the mixed signal on the surface of the test piece with the coded excitation signal to obtain a defect characteristic signal related to the coded excitation signal. A detection module is configured to analyze the defect characteristic signal to obtain a defect detection result of the test piece.
[0015] In a third aspect, the present application provides an electronic device including a memory and a processor, the memory storing a computer program, and the processor implementing the steps of the magnetic flux leakage detection anti-interference method based on coded excitation and synchronous decoding when executing the computer program.
[0016] In a fourth aspect, the present application provides a storage medium having a computer program stored thereon, the computer program being executed by a processor to implement the steps of the magnetic flux leakage detection anti-interference method based on coded excitation and synchronous decoding.
[0017] Compared with the prior art, the present application has the following beneficial effects: The magnetic flux leakage detection anti-interference method based on coded excitation and synchronous decoding actively distinguishes the defect leakage magnetic signal and the environmental noise through the coding-decoding mechanism, rather than passively filtering them out. On the other hand, the coded excitation signal is power-amplified to obtain a power-amplified coded excitation signal, which can maintain the coded characteristics of the excitation signal and has a higher amplitude, and is less susceptible to electromagnetic interference during transmission.
[0018] Further, the present application discloses encoding the excitation signal to obtain a digital coded sequence, specifically, a pseudo-random sequence is used to encode the excitation signal to obtain a digital coded sequence, the digital coded sequence being one of a pseudo-random sequence, a linear frequency modulation signal or a multi-frequency orthogonal signal. The present application utilizes the sharp autocorrelation characteristics of the pseudo-random sequence and other encodings to effectively suppress various broadband and narrowband interferences, and significantly improves the signal-to-noise ratio. BRIEF DESCRIPTION OF DRAWINGS
[0019] Figure 1 A flowchart of the magnetic flux leakage detection anti-interference method based on coded excitation and synchronous decoding of the present application; Figure 2 A schematic diagram of the magnetic flux leakage detection anti-interference system based on coded excitation and synchronous decoding of the present application; Figure 3 Figure 4 is a structural block diagram of the anti-interference detection environment of the magnetic flux leakage detection based on coded excitation and synchronous decoding in Embodiment 4 of the present application; Figure 4 Figure 5 is a structural schematic diagram of the electronic device. DETAILED DESCRIPTION
[0020] In order to further understand the content of the present application, the present application is described in detail below in combination with the drawings and specific embodiments. It should be understood that the embodiments are merely used to explain the present application but not to limit the present application.
[0021] Embodiment 1: Figure 1 is a flowchart of the anti-interference method of the magnetic flux leakage detection based on coded excitation and synchronous decoding in the present application. Figure 1 The anti-interference method of the magnetic flux leakage detection based on coded excitation and synchronous decoding in the present application includes the following steps: S1. obtaining an excitation signal; S2. coding the excitation signal to obtain a digital coded sequence; S3. modulating the digital coded sequence to a carrier wave with a set frequency to obtain a coded excitation signal; S4. power amplifying the coded excitation signal to obtain a power amplified coded excitation signal; S5. magnetizing a test piece based on the power amplified coded excitation signal to construct a magnetic field with coded characteristics; S6. obtaining a mixed signal on the surface of the test piece, wherein the mixed signal includes a defect magnetic flux leakage signal and environmental noise; S7. synchronously decoding the mixed signal on the surface of the test piece with the coded excitation signal to obtain a defect characteristic signal related to the coded excitation signal; S8. analyzing the defect characteristic signal to obtain a defect detection result of the test piece.
[0022] Embodiment 2: Figure 2 is a schematic diagram of the anti-interference system of the magnetic flux leakage detection based on coded excitation and synchronous decoding in the present application. Figure 2 The anti-interference system of the magnetic flux leakage detection based on coded excitation and synchronous decoding in the present application includes: a data acquisition module for obtaining an excitation signal; a coding module for coding the excitation signal to obtain a digital coded sequence; a modulation module for modulating the digital coded sequence to a carrier wave with a set frequency to obtain a coded excitation signal; a power amplification module for power amplifying the coded excitation signal to obtain a power amplified coded excitation signal; A magnetization module is configured to magnetize the test piece based on the power-amplified coded excitation signal to construct a magnetic field with coded characteristics. A mixed signal acquisition module is configured to acquire a mixed signal on the surface of the test piece, wherein the mixed signal comprises a defect magnetic leakage signal and environmental noise. A decoding module is configured to synchronously decode the mixed signal on the surface of the test piece with the coded excitation signal to obtain a defect characteristic signal related to the coded excitation signal. A detection module is configured to analyze the defect characteristic signal to obtain a defect detection result of the test piece.
[0023] Embodiment 3: The magnetic leakage detection anti-interference method based on coded excitation and synchronous decoding comprises the following steps: S1. An excitation signal is acquired.
[0024] S2. The excitation signal is coded to obtain a digital coded sequence.
[0025] In this step, the excitation signal is coded to obtain a digital coded sequence, specifically, the excitation signal is coded by using a pseudo-random sequence to obtain a digital coded sequence.
[0026] The digital coded sequence is one of a pseudo-random sequence, a linear frequency modulation signal or a multi-frequency orthogonal signal.
[0027] The pseudo-random sequence is an m-sequence or a Gold sequence.
[0028] S3. The digital coded sequence is modulated to a carrier with a set frequency to obtain a coded excitation signal.
[0029] S4. The coded excitation signal is power-amplified to obtain a power-amplified coded excitation signal.
[0030] S5. The test piece is magnetized based on the power-amplified coded excitation signal to construct a magnetic field with coded characteristics.
[0031] S6. A mixed signal on the surface of the test piece is acquired, wherein the mixed signal comprises a defect magnetic leakage signal and environmental noise.
[0032] In this step, the mixed signal on the surface of the test piece is acquired, specifically, the mixed signal on the surface of the test piece is acquired by using a magnetic sensor array.
[0033] S7. The mixed signal on the surface of the test piece is synchronously decoded with the coded excitation signal to obtain a defect characteristic signal related to the coded excitation signal.
[0034] The synchronous decoding is cross-correlation operation or matched filtering.
[0035] Before the mixed signal of the surface of the test piece and the environmental noise is synchronized and decoded with the coded excitation signal to obtain the defect characteristic signal related to the coded excitation signal, the mixed signal of the surface of the test piece and the environmental noise is amplified and filtered for pretreatment.
[0036] S8. Analyzing the defect characteristic signal to obtain a defect detection result of the test piece.
[0037] Embodiment 4: The magnetic flux leakage detection anti-interference method based on coded excitation and synchronous decoding includes the following steps: Step 1: excitation signal coding A digital coded sequence with good autocorrelation characteristics is generated, which is modulated to a carrier wave of a certain frequency to form a coded excitation signal. The preferred coded sequence is a pseudo-random code.
[0038] Step 2: coded excitation After the coded excitation signal is power amplified, it is applied to the excitation device to magnetize the test piece, so that a magnetic field with coded characteristics is established inside the test piece.
[0039] Step 3: signal synchronous acquisition A high-sensitivity magnetic sensor array is used to synchronously acquire the magnetic field signal on the surface of the component. The signal is a mixture of the coded magnetic flux leakage signal caused by defects and environmental noise.
[0040] Step 4: synchronous decoding The acquired mixed signal is cross-correlated with the coded excitation signal or matched filtered (synchronous decoding). Since the defect signal is related to the coded excitation signal and not related to the noise, the cross-correlation operation will highlight the defect signal and greatly suppress the noise.
[0041] Step 5: defect detection The defect characteristic signal obtained after decoding, with significantly improved signal-to-noise ratio, is analyzed to obtain a defect detection result of the test piece.
[0042] The method of the present application is implemented by Figure 3 This embodiment takes detecting artificial defects in a flat weld of a Q235 steel plate as an example to illustrate the method of the present application in detail: 1. Build a detection environment (detection environment is referred to as system) The detection environment mainly includes: Coded excitation module (also called coded signal generator): Xilinx Artix-7 series FPGA (Field-Programmable Gate Array) is used to generate an m-sequence with a code length of 127 bits, and the carrier frequency is 50 Hz.
[0043] Power amplifier: output current maximum 10A, voltage ±24V.
[0044] Excitation device: U-shaped silicon steel sheet yoke, 2000 turns of enameled wire coil wound thereon.
[0045] Magnetic sensor (tunnel magnetoresistance sensor) array: 8 TMR2105 sensors are arranged in a one-dimensional linear array with a spacing of 5mm.
[0046] Signal conditioning module: includes an amplification circuit based on AD620 and an active filter circuit based on UAF42.
[0047] Synchronous decoding processing module (also called synchronous decoding processor): a digital correlator is implemented in the same FPGA for real-time cross-correlation calculation.
[0048] Control and display unit: an industrial computer running LabVIEW program for data analysis and display.
[0049] The components in the detection environment and the connection relationship between the components are described as follows: The coded excitation module is used to generate and output a coded excitation signal. The power amplification module is connected with the coded excitation module and is used to amplify the coded excitation signal. The excitation device is connected with the power amplification module and is used to magnetize the test piece according to the amplified coded excitation signal. The magnetic sensor array is used to collect the mixed magnetic flux leakage signal. The signal conditioning module is connected with the magnetic sensor array and is used to preprocess the mixed signal. The synchronous decoding processing module is connected with the coded excitation module and the signal conditioning module, respectively, and is used to receive the reference signal and the preprocessed mixed signal, and extract the defect feature signal through synchronous decoding processing. The control and display unit is connected with the synchronous decoding processing module, and is used to control the entire system and analyze the defect feature signal to detect defects, and can visually display the defect detection results of the test piece.
[0050] 2. Detection process Place the excitation device and the sensor probe on the surface of the steel plate to be tested.
[0051] The FPGA generates a coded excitation signal, which drives the excitation coil after power amplification, magnetizing the steel plate.
[0052] The TMR sensor array synchronously collects the magnetic flux leakage signal, which is amplified and filtered by the conditioning circuit, and then converted into a digital signal by the ADC.
[0053] The digital correlator in the FPGA performs cross-correlation operation on the collected digital signal and a local m-sequence reference signal.
[0054] The result of the cross-correlation operation (i.e., the defect feature signal) is transmitted to an industrial computer.
[0055] The computer software analyzes the defect feature signals of the 8 channels, locates the defects by finding the correlation peaks, and evaluates the defect size according to the peak amplitudes.
[0056] 3. Result comparison In order to verify the effect of the application, a 0.5mm-wide and 2mm-deep artificial slot defect is detected by using the traditional DC excitation and the method of the application respectively under the same environment. The experimental results show that, in the case of introducing strong power frequency interference, the signal-to-noise ratio of the traditional method is about 10dB, and the defect feature is almost submerged; after using the method of the application, the signal-to-noise ratio is improved to more than 30dB, and the defect signal is clear and identifiable, and the positioning is accurate.
[0057] In summary, the application effectively solves the anti-interference problem in magnetic flux leakage detection, and provides strong technical support for realizing high-reliability and high-precision automatic nondestructive testing.
[0058] Compared with the prior art, the application has the following beneficial effects: Active anti-interference: starting from the signal source, actively distinguishing signals and noises through encoding-decoding mechanism, rather than passive filtering.
[0059] High signal-to-noise ratio improvement: using the sharp autocorrelation characteristics of pseudo-random sequences and other encodings, various broadband and narrowband interferences can be effectively suppressed, and the signal-to-noise ratio is significantly improved.
[0060] Strong robustness: not sensitive to slight fluctuations of excitation current, good system stability.
[0061] Easy to integrate and expand: the core algorithm can be realized in real time on FPGA / DSP, easy to integrate with existing detection systems, and can be expanded for multi-channel frequency division multiplexing, further improving the detection efficiency.
[0062] Embodiment 5: Please refer to Figure 4 The application also provides an electronic device 100 for magnetic flux leakage detection anti-interference method based on coded excitation and synchronous decoding, as shown in the drawings; the electronic device 100 comprises a memory 101, at least one processor 102, a computer program 103 stored in the memory 101 and capable of running on the at least one processor 102, and at least one communication bus 104.
[0063] The memory 101 can be used to store the computer program 103, and the processor 102 can realize the steps of the magnetic leakage detection anti-interference method based on the encoding excitation and synchronous decoding by running or executing the computer program stored in the memory 101 and calling the data stored in the memory 101. The memory 101 can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application program required by a function (such as a sound playing function, an image playing function, etc.), and the like; and the data storage area can store data (such as audio data) created according to the use of the electronic device 100. In addition, the memory 101 can include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device.
[0064] The at least one processor 102 can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The processor 102 can be a microprocessor or can also be any conventional processor, etc. The processor 102 is the control center of the electronic device 100, and is connected to various parts of the electronic device 100 through various interfaces and lines.
[0065] The memory 101 in the electronic device 100 stores a plurality of instructions to realize the magnetic leakage detection anti-interference method based on the encoding excitation and synchronous decoding, and the processor 102 can execute the plurality of instructions to realize: obtaining an excitation signal; encoding the excitation signal to obtain a digital encoding sequence; modulating the digital encoding sequence onto a carrier wave of a set frequency to obtain an encoded excitation signal; power amplifying the encoded excitation signal to obtain a power-amplified encoded excitation signal; magnetizing a test piece based on the power-amplified encoded excitation signal to construct a magnetic field with an encoding characteristic; Acquire a mixed signal of a surface of a test piece, the mixed signal comprising a defect leakage magnetic signal and environmental noise; Synchronously decode the mixed signal of the surface of the test piece with a coded excitation signal to obtain a defect characteristic signal related to the coded excitation signal; Analyze the defect characteristic signal to obtain a defect detection result of the test piece.
[0066] Embodiment 6: The modules / units integrated in the electronic device 100, if realized in the form of software function units and sold or used as independent products, can be stored in a computer readable storage medium. Based on such understanding, all or part of the processes in the above-mentioned embodiment methods can also be completed by a computer program instructing related hardware, and the computer program can be stored in a computer readable storage medium. When the computer program is executed by a processor, the steps of the above-mentioned various method embodiments can be implemented. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or some intermediate forms, etc. The computer readable medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, and read-only memory (ROM).
[0067] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program code.
[0068] The present application is described with reference to flowcharts and / or block diagrams according to the method, device (system), and computer program product of the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device that implements the functions specified in the flowcharts and / or block diagrams. Figure 1 The device that implements the functions specified in one flow or multiple flows and / or blocks Figure 1 The device that implements the functions specified in one flow or multiple flows and / or blocks
[0069] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.
[0070] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.
[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.
Claims
1. A leakage flux detection anti-interference method based on coded excitation and synchronous decoding, characterized in that, Includes the following steps: Obtain the excitation signal; The excitation signal is encoded to obtain a digital encoded sequence; The digital coded sequence is modulated onto a carrier wave of a set frequency to obtain the coded excitation signal; The coded excitation signal is amplified to obtain the amplified coded excitation signal. Based on the coded excitation signal after power amplification, the test piece is magnetized to construct a magnetic field with coded characteristics; Acquire a mixed signal from the surface of the test piece, the mixed signal including defect leakage magnetic field signal and environmental noise; The mixed signal on the surface of the test piece is synchronously decoded with the coded excitation signal to obtain the defect feature signal related to the coded excitation signal; The defect feature signals are analyzed to obtain the defect detection results of the test piece.
2. The leakage flux detection and anti-interference method based on coded excitation and synchronous decoding according to claim 1, characterized in that, The process of encoding the excitation signal to obtain a digital encoding sequence specifically involves using a pseudo-random sequence to encode the excitation signal to obtain a digital encoding sequence.
3. The leakage flux detection and anti-interference method based on coded excitation and synchronous decoding according to claim 1, characterized in that, The digital encoding sequence is one of a pseudo-random sequence, a linear frequency modulated signal, or a multi-frequency orthogonal signal.
4. The leakage flux detection and anti-interference method based on coded excitation and synchronous decoding according to claim 3, characterized in that, The pseudo-random sequence is an m-sequence or a Gold sequence.
5. The leakage flux detection and anti-interference method based on coded excitation and synchronous decoding according to claim 1, characterized in that, The acquisition of the mixed signal on the surface of the test piece specifically involves using a magnetic sensor array to acquire the mixed signal on the surface of the test piece.
6. The leakage flux detection and anti-interference method based on coded excitation and synchronous decoding according to claim 1, characterized in that, The synchronous decoding is performed by cross-correlation or matched filtering.
7. The leakage flux detection and anti-interference method based on coded excitation and synchronous decoding according to claim 1, characterized in that, Before synchronously decoding the mixed signal on the surface of the test piece with the coded excitation signal to obtain the defect feature signal related to the coded excitation signal, the mixed signal and environmental noise on the surface of the test piece are amplified and filtered for preprocessing.
8. A leakage flux detection and anti-interference system based on coded excitation and synchronous decoding, characterized in that, include: The data acquisition module is used to acquire excitation signals; The encoding module is used to encode the excitation signal to obtain a digital encoded sequence; The modulation module is used to modulate the digital coded sequence onto a carrier wave of a set frequency to obtain a coded excitation signal; The power amplifier module is used to amplify the power of the coded excitation signal to obtain the amplified coded excitation signal. The magnetization module is used to magnetize the test piece based on the coded excitation signal after power amplification, thereby constructing a magnetic field with coded characteristics. A mixed signal acquisition module is used to acquire mixed signals from the surface of the test piece, the mixed signals including defect leakage magnetic field signals and environmental noise; The decoding module is used to synchronously decode the mixed signal on the surface of the test piece and the coded excitation signal to obtain the defect feature signal related to the coded excitation signal; The detection module is used to analyze the defect feature signals to obtain the defect detection results of the test piece.
9. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the leakage magnetic field detection anti-interference method based on coded excitation and synchronous decoding as described in any one of claims 1 to 7.
10. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the leakage magnetic field detection anti-interference method based on coded excitation and synchronous decoding as described in any one of claims 1 to 7.