Dynamic electromagnetic shielding method for complex electromagnetic environment and shielding device thereof

Abstract

The invention discloses a dynamic electromagnetic shielding method for a complex electromagnetic environment and a shielding device thereof, and the method comprises the steps: obtaining real-time voltage data in the complex electromagnetic environment, carrying out the voltage feature analysis, outputting a feature vector of a real-time voltage signal, and analyzing the type of an interference source of a current electric field according to the feature vector, performing interference trend time sequence prediction processing on the feature vector through a pre-trained LSTM model according to the interference source type to obtain a time domain voltage value and a phase deviation value, and performing composite loss coefficient calculation on the time domain voltage value and the phase deviation value to obtain a composite loss coefficient; and performing reverse offset signal synthesis processing on the voltage interference signal according to the calculated composite loss coefficient, performing coil dynamic activation processing on a preset multi-coil array according to the synthesized reverse offset signal, generating a directional offset magnetic field corresponding to the real-time electromagnetic interference, and performing electromagnetic offset shielding on the current electromagnetic interference. According to the invention, transient interference can be responded in time, and the electromagnetic shielding effectiveness can be improved.

Description

Technical Field

[0001] This invention relates to the technical field of electromagnetic shielding, and in particular to a dynamic electromagnetic shielding method and shielding device for complex electromagnetic environments. Background Technology

[0002] Currently, voltage sensors have seen significant development in the field of electrical engineering. As a core component in critical applications such as power systems, industrial automation, and safety monitoring, their performance directly affects the safe operation and efficiency of the entire system. With the continuous expansion of application scenarios, the market demand for high-precision and high-reliability sensors continues to rise. Traditional static shielding methods mainly focus on improving measurement accuracy and accelerating response speed, but timely electromagnetic interference shielding of voltage sensors in complex electromagnetic environments faces multiple challenges.

[0003] In actual power grid operation, electromagnetic interference mainly manifests in three typical forms: power frequency interference, partial discharge interference, and pulse interference. Power frequency harmonic interference, as the type of interference with the highest probability of occurrence, mainly propagates in power lines through conduction and is mainly generated by nonlinear loads and new energy grid-connected equipment. Although pulse interference has the characteristics of instantaneous high intensity, it is also intermittent and includes both conduction and radiation propagation modes. In practical applications, partial discharge interference is mainly considered. It is prone to occur when equipment insulation has defects or equipment begins to age. The transient electromagnetic pulses generated by partial discharge (PD) interference have a frequency between 300MHz and 3GHz. This type of interference radiates into space in the form of electromagnetic waves. Traditional static shielding methods mainly focus on improving measurement accuracy, response speed, and environmental adaptability. However, in complex electromagnetic environments, existing static shielding technologies face severe challenges. Static metal shielding shells are effective against low-frequency conducted interference, but their attenuation capability against high-frequency radiated interference of 300MHz–3GHz drops sharply. Furthermore, ventilation holes added to voltage sensors to ensure heat dissipation can easily form electromagnetic leakage paths. Conventional metal mesh structures have limited cutoff effects against high-frequency electromagnetic waves. Static shielding cannot respond to transient interference in real time and change the electromagnetic environment in a timely manner, resulting in significant fluctuations in shielding effectiveness. Summary of the Invention

[0004] To address the problem that static shielding in existing technologies cannot respond promptly to electromagnetic interference shielding requirements in complex electromagnetic environments, this invention provides a dynamic electromagnetic shielding method and shielding device for complex electromagnetic environments, which can respond promptly to transient interference and improve electromagnetic shielding effectiveness.

[0005] Firstly, the above-mentioned inventive objective of this application is achieved through the following technical solution: A dynamic electromagnetic shielding method for complex electromagnetic environments, the method comprising: Acquire real-time voltage data under complex electromagnetic environments and perform voltage characteristic analysis, output the feature vector of the real-time voltage signal, and analyze the type of interference source of the current electric field based on the feature vector; Based on the type of interference source, the feature vector is subjected to time-series prediction of interference trend using a pre-trained LSTM model to obtain time-domain voltage value and phase shift value. The composite loss coefficient is calculated for the time-domain voltage value and the phase offset value, and the voltage interference signal is processed by reverse cancellation signal synthesis based on the calculated composite loss coefficient. Based on the synthesized reverse cancellation signal, the preset multi-coil array is dynamically activated to generate a directional cancellation magnetic field corresponding to the real-time electromagnetic interference, thereby electromagnetically cancelling and shielding the current electromagnetic interference.

[0006] In a preferred embodiment, this application can be further configured such that the method also includes: The residual field strength after electromagnetic cancellation and shielding is acquired in real time. When the residual field strength reaches a preset threshold, the time domain voltage value and the phase offset value are dynamically adjusted to generate the corresponding single adjustment result. Based on the single adjustment result, calculate the corresponding adjustment amplitude gradient of the time-domain voltage value and the phase offset value, and analyze the cancellation direction of the residual field strength; Based on the adjustment amplitude gradient and the corresponding cancellation direction, the time-domain voltage value and the phase offset value are subjected to independent disturbance cancellation processing to obtain the corresponding independent cancellation signal; The electromagnetic cancellation shielding result of the independent cancellation signal is compared with the preset threshold of the residual field strength, and the time-domain voltage value and the phase offset value are cyclically adjusted according to the feedback comparison result to obtain dynamic closed-loop control data.

[0007] In a preferred embodiment, this application can be further configured as follows: The real-time acquisition of the residual field strength after electromagnetic cancellation shielding, and the dynamic adjustment of the time-domain voltage value and the phase shift value when the residual field strength reaches a preset threshold, generating a corresponding single adjustment result, specifically includes the following: The voltage signal corresponding to the residual field strength is subjected to frequency domain transformation, and the main interference frequency is extracted. Each main interference frequency is then subjected to independent orthogonal adjustment, wherein the orthogonal adjustment expression is as follows: (1) (2) in, Indicates the first frequency band within the target frequency band. One main interference frequency; The projection component of each of the main interference frequencies is calculated, and the expression for the projection component is as follows: (3) (4) in, , This represents a one-dimensional array obtained from storing voltage signals. =5ns; The amplitude error and phase error of the main interference frequency are calculated based on the projection components, and the relevant time-domain voltage value and phase offset value are dynamically adjusted to compensate for the deviation. The expression for the amplitude error is as follows: (5) The phase error expression is as follows: (6) in, , These represent the amplitude error value and the phase error value, respectively. Indicates the first The target residual amplitude at the main interference frequency.

[0008] In a preferred embodiment, this application can be further configured as follows: the adjustment amplitude gradient is calculated based on the single adjustment result, corresponding to the time-domain voltage value and the phase offset value, and the direction of cancellation of the residual field strength is analyzed. The adjustment amplitude gradient calculation process specifically includes: The disturbance amplitude parameter of the residual field strength is adjusted based on the single adjustment result, wherein the expression of the disturbance amplitude parameter is as follows: (7) in, Indicates the first Updated values ​​of the disturbance amplitude parameters for each main interference frequency. Indicates the first Initial values ​​of the disturbance amplitude parameters for each main interference frequency. Δk =0.01; The disturbance amplitude is adjusted according to the adjusted disturbance amplitude parameters at the corresponding main disturbance frequency, and the amplitude gradient corresponding to the time-domain voltage value is calculated. The expression for the amplitude gradient is as follows: (8) in, Indicates the disturbance parameters The magnitude gradient adjustment value corresponding to the change , Indicates the disturbance parameters The amplitude of the residual signal after the disturbance , This represents the residual signal amplitude before the disturbance. The perturbation phase parameter of the residual field strength is adjusted based on the single adjustment result, wherein the expression of the perturbation phase parameter is as follows: (9) in, Indicates the first Updated values ​​of the disturbance phase parameters for each main interference frequency. Indicates the first Initial values ​​of the disturbance phase parameters for each main interference frequency. =0.01; Based on the adjusted disturbance phase parameters, the corresponding main interference frequency is subjected to disturbance phase adjustment, and the phase gradient corresponding to the phase offset value is calculated, wherein the expression for the phase gradient is as follows: (10) in, Indicates the disturbance parameters The corresponding phase gradient adjustment value for the change , Indicates the disturbance parameters The phase of the residual signal after the disturbance. , This indicates the residual signal phase before any disturbance.

[0009] In a preferred embodiment, this application may be further configured as follows: after calculating the corresponding adjustment amplitude gradients of the time-domain voltage value and the phase offset value based on the single adjustment result, and analyzing the cancellation direction of the residual field strength, the application further includes: Based on the amplitude error and the corresponding cancellation direction, the time-domain voltage value after the deviation is cancelled is updated, and the expression for the updated time-domain voltage value is as follows: (11) in, This represents the updated time-domain voltage value parameter. Indicates the first Initial values ​​of the disturbance amplitude parameters for each main interference frequency. Indicates the first The amplitude update step size coefficient for each main interference frequency has a value range of (0,1). Indicates amplitude error. This indicates the cancellation direction corresponding to the amplitude gradient adjustment, determined by the amplitude gradient of the time-domain voltage value. Decide; Based on the phase error and the corresponding cancellation direction, the phase offset value after the offset deviation is updated. The expression for the updated phase offset value is as follows: (12) in, This represents the updated phase offset value. Indicates the first Initial values ​​of the disturbance phase parameters for each main interference frequency. Indicates the first The phase update step size coefficient for each main interference frequency ranges from (0,1). Indicates phase error, This indicates the cancellation direction corresponding to the phase gradient adjustment, which is determined by the magnitude gradient and phase gradient of the phase offset value.

[0010] In a preferred embodiment, this application can be further configured as follows: the process of acquiring real-time voltage data under complex electromagnetic environments and performing voltage feature analysis, outputting feature vectors of real-time voltage signals, and analyzing voltage feature analysis of the interference source types in the current electric field based on the feature vectors specifically includes: The harmonic distortion rate vector in the voltage characteristics is calculated using formula (13), and the expression for the harmonic distortion rate vector is as follows: (13) in, This represents the amplitude of the 50Hz fundamental frequency. Indicates the first Second harmonic amplitude ; The pulse rise time vector in the voltage characteristics is calculated using formula (14), and the expression for the pulse rise time vector is as follows: (14) in, This indicates the time it takes for the pulse to rise to 90% of its peak value. This indicates the time it takes for the pulse to rise to 10% of its peak value; The spectral entropy vector in the voltage characteristics is calculated using formula (15), and the expression for the spectral entropy vector is as follows: (15) in, Represents frequency Normalization, , This represents the frequency point amplitude obtained by performing a Fourier transform on the real-time voltage data. Indicates the number of frequency points sampled; The carrier offset variance vector in the voltage characteristics is calculated using formula (16), and the expression for the carrier offset variance vector is as follows: (16) in, express Instantaneous frequency within the time period This indicates the average frequency within a set time window.

[0011] In a preferred embodiment, this application can be further configured as follows: calculating a composite loss coefficient for the time-domain voltage value and the phase offset value, and performing reverse cancellation signal synthesis processing on the voltage interference signal based on the calculated composite loss coefficient, specifically including: The composite loss coefficient is calculated using formula (17), and the expression for the composite loss coefficient is as follows: (17) in, The time-domain voltage loss coefficient is represented by the following formula: (18) in, The phase offset loss coefficient is represented by the formula shown below: (19) in, , It is a constant. Indicates the first Predicted time-domain voltage values ​​at each voltage sampling point Indicates the first The true time-domain voltage value of each voltage sampling point Indicates the first Predicted phase of each voltage sampling point Indicates the first The true phase of each voltage sampling point; Based on the time-domain voltage value and the phase offset value, the waveform trend of the interfering electromagnetic wave is predicted to obtain the voltage interference prediction waveform; The time-domain voltage value and phase of the voltage interference signal are adjusted in reverse according to the composite loss coefficient, and the voltage interference prediction waveform is fitted in reverse to obtain the reverse cancellation signal synthesis result of the voltage interference signal.

[0012] In a preferred embodiment, this application can be further configured as follows: the reverse cancellation fitting process in the reverse cancellation signal synthesis result of the voltage interference signal, which involves adjusting the time-domain voltage value and phase of the voltage interference signal in reverse according to the composite loss coefficient, and performing reverse cancellation fitting on the voltage interference prediction waveform, specifically includes: Formula (20) represents the inverse cancellation signal of the voltage interference prediction waveform. The voltage interference signal is fitted with the inverse cancellation signal, and Formula (20) is shown below: (20) in, Indicates the reverse cancellation signal. This represents the output signal after phase shift. This represents the time-domain voltage value obtained by adjusting the composite loss coefficient. This represents the reference signal obtained after phase adjustment. This indicates the phase obtained by adjusting the composite loss coefficient. Represents angular frequency. This indicates the sampling time of the voltage interference signal.

[0013] Secondly, the above-mentioned inventive objective of this application is achieved through the following technical solutions: A dynamic electromagnetic shielding device for complex electromagnetic environments is disclosed, wherein the dynamic electromagnetic shielding device is applied to the aforementioned dynamic electromagnetic shielding method for complex electromagnetic environments. The electromagnetic shielding device includes: an electric field probe, a base, and a rigid metal shell fixed to the base. A closed cavity is formed between the base and the rigid metal shell. An oxide coating is provided on the side wall of the rigid metal shell located in the closed cavity. The electric field probe is fixed to the base and located within the closed cavity. The electromagnetic shielding device further includes a curved shell covering the side of the rigid metal shell away from the base. A waveguide ventilation plate communicating with the curved shell and the closed cavity is provided on the rigid metal shell. Both outlets of the waveguide ventilation plate are covered with conductive mesh.

[0014] In summary, this application includes at least one of the following beneficial technical effects: 1. This application achieves efficient suppression of high-frequency electromagnetic interference such as partial discharge through the synergistic design of a two-layer composite shielding shell device and active dynamic cancellation technology. The outer aluminum Faraday cage and inner ferrite coating of the hardware shielding shell, combined with the design of hexagonal honeycomb waveguide ventilation holes, significantly improve the passive shielding effectiveness while ensuring mechanical protection and heat dissipation requirements. The dynamic electromagnetic shielding method is based on a decision tree classification algorithm using voltage feature vectors to accurately distinguish between power frequency harmonics, partial discharge and pulse interference types, providing operating condition basis for dynamic tuning. Furthermore, the LSTM time series prediction model generates cancellation parameters for future interference evolution trends in real time, solving the problem of insufficient adaptability of traditional static shielding to transient interference. It can respond to transient interference in a timely manner and improve electromagnetic shielding effectiveness.

[0015] 2. This application predicts interference trends based on the type of interference source and analyzes the corresponding time-domain voltage and phase shift values, thereby calculating the corresponding composite loss coefficient. This coefficient is used to perform reverse cancellation signal synthesis processing on the voltage interference signal. Based on the reverse cancellation signal, a multi-coil array is dynamically activated to generate a directional cancellation magnetic field corresponding to the real-time electromagnetic interference, thereby performing directional cancellation shielding on the electromagnetic interference. Compared with the traditional static shielding method, this method can adapt to the electromagnetic shielding accuracy requirements of complex electromagnetic environments. When electromagnetic interference is detected, it can respond to transient interference in a timely manner and adjust the cancellation magnetic field parameters in a timely manner, thereby improving the shielding effectiveness of high-frequency radiation interference in complex electromagnetic environments. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0017] Figure 1 This is a flowchart illustrating the implementation of the dynamic electromagnetic shielding method for complex electromagnetic environments in this embodiment.

[0018] Figure 2 This is a flowchart illustrating the implementation of step S30 of the dynamic electromagnetic shielding method in this embodiment.

[0019] Figure 3 This is a flowchart illustrating the implementation of dynamic closed-loop control using the dynamic electromagnetic shielding method in this embodiment.

[0020] Figure 4 This is a flowchart illustrating the implementation of parameter adjustment in the dynamic electromagnetic shielding method of this embodiment.

[0021] Figure 5 This is a flowchart illustrating the implementation of step S60 of the dynamic electromagnetic shielding method in this embodiment.

[0022] Figure 6 This is a flowchart illustrating the implementation of independent disturbance cancellation in this embodiment.

[0023] Figure 7 This is a data processing flowchart of the dynamic electromagnetic shielding device in this embodiment.

[0024] Figure 8 This is a schematic diagram of the dynamic electromagnetic shielding device in this embodiment.

[0025] Figure 9 This is a cross-sectional view of the dynamic electromagnetic shielding device in this embodiment.

[0026] Figure 10 This is a schematic diagram of the internal structure of a computer device used to implement dynamic electromagnetic shielding.

[0027] Explanation of reference numerals in the attached figures: 1. Hard metal casing; 2. Inner conductive mesh; 3. Outer conductive mesh; 4. Electric field probe; 5. Waveguide ventilation plate; 6. Base. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0030] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0031] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0032] In one embodiment, such as Figure 1As shown, this application discloses a dynamic electromagnetic shielding method for complex electromagnetic environments, which specifically includes the following steps: S10: Acquire real-time voltage data under complex electromagnetic environments and perform voltage feature analysis, output the feature vector of the real-time voltage signal, and analyze the type of interference source of the current electric field based on the feature vector.

[0033] Specifically, the real-time voltage signal of the interfering electric field is acquired by an electric field probe and processed, including data cleaning, digital-to-analog conversion, and Fourier transform. The processed data is then transmitted to a preset FPDA module for voltage feature analysis to obtain the feature vector of the real-time voltage signal and the type of interference source corresponding to the current electric field. The feature vector includes harmonic distortion rate, pulse rise time, spectral entropy, and carrier offset variance. The interference source types include power frequency interference, partial discharge interference, and pulse interference.

[0034] This embodiment employs an anti-aliasing filter design, using a cavity filter (0.8-3.2GHz) for high-frequency electromagnetic pulses. For electromagnetic waves in the 300MHz-3GHz band, an Aronia HyperLOG3080 probe and a TI ADC12DJ5200RF (12-bit) ADC are selected. The probe output signal, after passing through a dedicated filter, is sampled and digitized by the corresponding ADC, and transmitted to the FPGA (Xilinx KU115) for signal processing via the JESD204B interface.

[0035] Among them, the harmonic distortion rate vector in the voltage characteristics is calculated by formula (13), and the expression of the harmonic distortion rate vector is as follows: (13) in, This represents the amplitude of the 50Hz fundamental frequency. Indicates the first Second harmonic amplitude .

[0036] The pulse rise time vector in the voltage characteristic is calculated using formula (14). The expression for the pulse rise time vector is as follows: (14) in, This indicates the time it takes for the pulse to rise to 90% of its peak value. It represents the time it takes for the pulse to rise to 10% of its peak value. The pulse rise time (Tr) is the time required for the pulse signal to rise from 10% amplitude to 90% amplitude.

[0037] Specifically, find the maximum value within the sliding detection window (t), for example, the maximum value among the most recent 2000 sampling points. Set the threshold to 10%-90% of the maximum value. Starting from the pulse start point, i.e., the point where the signal exceeds 10% of the peak value, record the first time the peak value exceeds 10% at time t10 and search backwards, recording the first time the peak value exceeds 90% at time t90. Finally, calculate the pulse rise time. .

[0038] The spectral entropy vector in the voltage characteristics is calculated using formula (15). The expression for the spectral entropy vector is as follows: (15) in, Represents frequency Normalization, , This represents the frequency point amplitude obtained by performing a Fourier transform on the real-time voltage data. Indicates the number of frequency points sampled, when When =0, the spectral entropy vector is 0.

[0039] The carrier offset variance vector in the voltage characteristics is calculated using formula (16). The expression for the carrier offset variance vector is as follows: (16) in, express Instantaneous frequency within the time period The carrier offset variance (CFV) represents the average frequency within a set time window, reflecting the degree of fluctuation in the carrier frequency and thus the stability of the interference source.

[0040] Specifically, the analytic signal is obtained by performing a Hibernate transform on the real-time voltage signal. The expression of the analytic signal is as follows: (twenty one) in, H() is the Hilbert transform. Calculate the instantaneous phase using formula (22) Formula (22) is shown below: (twenty two) The instantaneous frequency is calculated using formula (23), which is shown below: (twenty three) in, The sampling interval is denoted as .

[0041] The average frequency is calculated using formula (24), which is shown below: (twenty four) S20: Based on the type of interference source, the feature vector is processed by a pre-trained LSTM model to perform time-series prediction of the interference trend, thereby obtaining the time-domain voltage value and phase shift value.

[0042] Specifically, in this embodiment, the data size is compressed through a 1D-CNN layer, so that the output is a feature vector with 4000 sampling points. The LSTM model is used for time-series prediction to predict the evolution trend of interference over a period of time. The model inputs the time-domain voltage value k and the phase shift θ to the active shielding layer. The active shielding layer generates canceling electromagnetic waves through a reconfigurable excitation coil system.

[0043] The LSTM model data in this embodiment comes from monitoring data obtained by detection probes under different operating conditions provided by China Southern Power Grid, covering three typical interference conditions: power frequency harmonic interference, partial discharge interference, and pulse interference. The data adopts an HDF5 (Hierarchical Data Format) hierarchical storage structure, with the file naming rule: [Interference Type]_[Timestamp]_[Acquisition Location].h5. The following six data variables are stored: synchronization timestamp, initial phase, interference source classification label, and time-domain voltage value.

[0044] The variable name for the synchronization timestamp is Timestamp, with nanosecond precision. The variable name for the initial phase is Phase, in radians, and the data type is float. The variable name for the interference source classification label is SourceType; in this embodiment, 0 represents power frequency harmonic interference, 1 represents partial discharge interference, and 2 represents pulse interference. The variable name for the time-domain voltage value is TimeDomain, and the data type is float32.

[0045] The training process of the LSTM model in this embodiment specifically includes: The raw data is processed in a data window of T, with the input variables being the time-domain voltage value, the real part of the initial phase, and the imaginary part of the initial phase. Here, the initial phase is converted from radians to a complex unit vector, resulting in two channels: the real part and the imaginary part. There are a total of three input data channels.

[0046] The time-domain voltage values ​​are normalized and scaled to the [-1, 1] interval. The normalization formula is as follows: (25) in, The voltage value before normalization. This is the set of all time-domain voltage values ​​in the data window.

[0047] The phase angle θ is converted into an orthogonal component on the unit circle to avoid the model training divergence problem caused by the periodicity of the angle.

[0048] The network structure of the LSTM model in this embodiment includes an input layer, a first LSTM layer, a second LSTM layer, a fully connected layer, a Dropout layer, and an output layer, specifically including: Input layer: 4000×3, where 4000 represents the number of sampling points in a single input, and 3 represents the number of input channels. The three channels are the time-domain voltage value, the real part of the initial phase, and the imaginary part of the initial phase, respectively.

[0049] The first LSTM layer consists of 192 LSTM units, each containing an input gate, a forget gate, an output gate, and a memory unit. The function of the first LSTM layer is primary temporal feature extraction.

[0050] The second LSTM layer has 64 LSTM units and its function is to extract deep features from the input data.

[0051] Fully connected layer: 32 neurons, activation function is ReLU.

[0052] Dropout layer: To prevent overfitting, a dropout rate of 0.2 is set, randomly dropping 20% ​​of the nodes and passing the rest on.

[0053] Output Layer: The output layer generates shielding control parameters. The activation function for the time-domain voltage value k branch is the Sigmoid function, with an output range of [-1, 1]. The activation function for the phase θ branch is Tanh×π, with an output range of [-π, π]. These parameters (k, θ) are transmitted to the active shielding drive circuit to control the synthesis of the cancellation signal.

[0054] The LSTM model is used to predict the time series of the feature vectors, and outputs the time-domain voltage value k and the phase offset value θ.

[0055] S30: Calculate the composite loss coefficient for the time-domain voltage value and phase offset value, and perform reverse cancellation signal synthesis processing on the voltage interference signal based on the calculated composite loss coefficient.

[0056] Specifically, a bi-branch composite loss function is used to optimize k and θ separately, such as... Figure 2 As shown, step S30 includes: S301: Calculate the composite loss coefficient using formula (17). The expression for the composite loss coefficient is as follows: (17) in, The time-domain voltage loss coefficient is represented by the following formula: (18) in, The phase offset loss coefficient is represented by the formula shown below: (19) in, , It is a constant. Indicates the first Predicted time-domain voltage values ​​at each voltage sampling point Indicates the first The true time-domain voltage value of each voltage sampling point Indicates the first Predicted phase of each voltage sampling point Indicates the first The true phase of each voltage sampling point; S302: Predict the waveform trend of the interfering electromagnetic wave based on the time-domain voltage value and phase offset value to obtain the voltage interference prediction waveform.

[0057] Specifically, based on the time-domain voltage value and phase shift value, combined with the corresponding timing sequence, the waveform trend of the interfering electromagnetic wave is predicted by the LSTM model, and the voltage interference prediction waveform is generated.

[0058] S303: Adjust the time-domain voltage value and phase of the voltage interference signal in reverse according to the composite loss coefficient, perform reverse cancellation fitting on the voltage interference prediction waveform, and obtain the reverse cancellation signal synthesis result of the voltage interference signal.

[0059] Specifically, the inverse cancellation signal of the voltage interference prediction waveform is represented by formula (20), and the voltage interference signal is fitted with the inverse cancellation signal. Formula (20) is shown below: (20) in, Indicates the reverse cancellation signal. This represents the output signal after phase shift. This represents the time-domain voltage value obtained by adjusting the composite loss coefficient. This represents the reference signal obtained after phase adjustment. This indicates the phase obtained by adjusting the composite loss coefficient. Represents angular frequency. This indicates the sampling time of the voltage interference signal.

[0060] Specifically, a reference signal that is at the same frequency as the interference source or contains the main frequency components of the interference is extracted from the interference source itself. , reference signal The time-domain voltage value obtained by adjusting the composite loss coefficient The product between the two values ​​is used to adjust the amplitude of the reference signal, and the adjusted reference signal is subjected to phase shift processing, which is expressed by formula (26), as shown below: (2 6) in, ， H{} represents the Hilbert transform, used to generate orthogonal components to achieve arbitrary phase shifts. The goal is to apply the phase shift θ of the model to the signal. This represents the phase obtained by adjusting the composite loss coefficient.

[0061] The digital drive signal obtained by merging and inverting The signal is converted into an analog voltage signal by a DAC digital-to-analog converter. And through a power amplifier (PA) Amplified into a high-power voltage signal This is to drive the coil to generate a sufficiently strong canceling magnetic field. The power amplifier (PA) in this embodiment is model MACOMMAAP-011152, and the operating frequency range of MACOMMAAP-011152 is DC-6GHz, which can perfectly cover 300MHz-3GHz.

[0062] The reverse cancellation signal is synthesized by fitting the reverse cancellation waveform corresponding to the reverse cancellation signal with the voltage interference prediction waveform according to the time sequence. In this embodiment, the reverse cancellation waveform is the same as the predicted voltage interference prediction waveform but has the opposite phase.

[0063] S40: Based on the synthesized reverse cancellation signal, the preset multi-coil array is dynamically activated to generate a directional cancellation magnetic field corresponding to the real-time electromagnetic interference, thereby performing electromagnetic cancellation shielding on the current electromagnetic interference.

[0064] Specifically, in this embodiment, the synthesized inverse cancellation signal can be amplified by a preset power amplifier (PA) to obtain an amplified high-frequency drive signal, and the high-frequency drive signal is applied to the excitation coil.

[0065] In this embodiment, the time-varying current generated by the excitation coil driven by the high-frequency drive signal produces a time-varying magnetic field in the surrounding space to shield against electromagnetic interference. This embodiment uses a multi-coil array to generate the electromagnetic shielding magnetic field.

[0066] In this embodiment, the individual coils of the multi-coil array are electrically connected to each other. Adjacent rectangular coil units are connected via a switching matrix to achieve area reconstruction. The series / parallel connection method, shape, and effective area of ​​the coils are dynamically changed based on the dominant frequency of the interference detected by the probe. The coils themselves are a fixed array. Through a high-speed switching matrix, the corresponding coils and their driving phase relationships are dynamically selected for activation based on the synthesized reverse cancellation signal, forming a specific cancellation magnetic field. Individual coils in the coil array use rectangular planar helical coils. Each coil unit has its own magnetic core, which improves low-frequency operating efficiency. Each coil unit is driven independently, and the phase of the driving signal is allocated through the switching matrix.

[0067] It should be noted that the multi-coil array can also be replaced with a coil structure that can be physically / electrically reconfigured. The electrically reconfigurable coil itself is a fixed array. Through a high-speed switching matrix, the corresponding coil and their driving phase relationship (in-phase, out-of-phase, specific phase difference) are dynamically selected and activated according to the synthesized reverse cancellation signal to form a directional cancellation magnetic field that accurately covers the sensitive area.

[0068] In this embodiment, an RFMEMS switch, specifically the Analog Devices ADGM1304, is selected. This switch has ultra-low on-resistance.

[0069] In this embodiment, after electromagnetic cancellation shielding is achieved through a multi-coil array, as... Figure 3 As shown, it also includes: S50: Real-time acquisition of residual field strength after electromagnetic cancellation shielding. When the residual field strength reaches a preset threshold, dynamic adjustment is performed on the time-domain voltage value and phase offset value respectively to generate the corresponding single adjustment result.

[0070] Specifically, the voltage signal after electromagnetic cancellation shielding is measured in real time using a 24-bit Σ-Δ ADC probe (such as ADS127L11) and stored as a one-dimensional array e (length N=4000). An FFT transformation is performed on array e to obtain the spectrum E_freq, and the power spectral density is calculated: PSD=|E_freq|². Significant peak values ​​of PSD are detected within the target frequency band (300MHz–3GHz), and the top M main interference frequencies (M is a preset value, such as M=3) are extracted, outputting a frequency list. =[f1,f2,..., The FFT transformation decomposes the time-domain signal into a frequency-domain energy distribution. The PSD peak corresponds to the strong interference frequency, providing a target for multi-frequency suppression.

[0071] In this embodiment, the residual field strength is calculated based on the voltage signal, and the residual field strength is fed back to the controller to analyze whether the residual field strength has reached a preset threshold. If the preset threshold is reached, the time-domain voltage value and phase offset value are adjusted in a timely manner. Figure 4As shown, it specifically includes: S501: Perform frequency domain transformation on the voltage signal corresponding to the residual field strength, extract the main interference frequency, and perform independent orthogonal adjustment on each main interference frequency. The orthogonal adjustment expression is as follows: (1) (2) in, Indicates the first frequency band within the target frequency band. One main interference frequency.

[0072] S502: Calculate the projected component for each main interference frequency. The expression for the projected component is as follows: (3) (4) in, , This represents a one-dimensional array obtained from storing voltage signals. =5ns; S503: Calculate the amplitude error and phase error of the main interference frequency according to the projection components, and dynamically adjust the relevant time-domain voltage value and phase offset value to compensate for the deviation.

[0073] The expression for the amplitude error is as follows: (5) The phase error expression is as follows: (6) in, , These represent the amplitude error value and the phase error value, respectively. Indicates the first The target residual amplitude of each main interference frequency is usually set to 0, indicating that it is expected to completely cancel the interference signal at the corresponding frequency.

[0074] when When the value is 0, the set of output errors is {( , )}( =1, 2, ..., M). The cancellation deviation of each frequency is quantized by projecting the main interference frequency into order. The residual signal is decomposed into I / Q vectors at a specific frequency by orthogonal adjustment. The magnitude reflects the amplitude mismatch and the phase difference reflects the inversion imperfection.

[0075] S60: Calculate the corresponding adjustment amplitude gradients for the time-domain voltage value and phase offset value based on the single adjustment results, and analyze the cancellation direction of the residual field strength.

[0076] Specifically, such as Figure 5 As shown, step S60 includes: S601: Adjust the disturbance amplitude parameter of the residual field strength based on the single adjustment result, wherein the expression for the disturbance amplitude parameter is as follows: (7) in, Indicates the first Updated values ​​of the disturbance amplitude parameters for each main interference frequency. Indicates the first The initial value of the disturbance amplitude parameter for each main interference frequency is Δk=0.01.

[0077] S602: Adjust the disturbance amplitude of the corresponding main interference frequency according to the adjusted disturbance amplitude parameters, and calculate the amplitude gradient corresponding to the time-domain voltage value. The expression for the amplitude gradient is as follows: (8) in, Indicates the disturbance parameters The magnitude gradient adjustment value corresponding to the change , Indicates the disturbance parameters The amplitude of the residual signal after the disturbance , This represents the residual signal amplitude before disturbance; the pass amplitude gradient adjustment value reflects... The impact of changes on global residual electromagnetic interference.

[0078] S603: Adjust the perturbation phase parameter of the residual field strength based on the single adjustment result, wherein the expression for the perturbation phase parameter is as follows: （9） in, Indicates the first Updated values ​​of the disturbance phase parameters for each main interference frequency. Indicates the first Initial values ​​of the disturbance phase parameters for each main interference frequency. =0.01rad.

[0079] S604: Adjust the perturbation phase of the corresponding main interference frequency according to the adjusted perturbation phase parameters, and calculate the phase gradient corresponding to the phase offset value. The phase gradient expression is as follows: （10） in, Indicates the disturbance parameters The corresponding phase gradient adjustment value for the change , Indicates the disturbance parameters The phase of the residual signal after the disturbance. , This indicates the residual signal phase before any disturbance.

[0080] In this embodiment, after calculating the corresponding adjustment amplitude gradients for the time-domain voltage value and phase shift value based on the single adjustment result, and analyzing the cancellation direction of the residual field strength, as follows... Figure 6 As shown, it also includes: S605: Based on the amplitude error and the corresponding cancellation direction, update the time-domain voltage value after offsetting the deviation. The expression for the updated time-domain voltage value is as follows: (11) in, This represents the updated time-domain voltage value parameter. Indicates the first Initial values ​​of the disturbance amplitude parameters for each main interference frequency. Indicates the first The amplitude update step size coefficient of each main interference frequency is used to control the update amplitude of the time-domain voltage value, and the value range is (0,1). Indicates amplitude error. Indicates the magnitude gradient The corresponding cancellation direction is adjusted, determined by the amplitude gradient of the time-domain voltage value. Specifically, when... When >0, =+1; when When <0, =-1.

[0081] S606: According to the corresponding cancellation direction and the calculated phase gradient, the phase is normalized so that the phase shift value is independently perturbed and canceled in the direction of decreasing residual energy. Specifically, the phase normalization expression is as follows: (12) in, This represents the updated phase offset value. Indicates the first Initial values ​​of the disturbance phase parameters for each main interference frequency. Indicates the first The phase update step size coefficient for each main interference frequency is used to control the update amplitude of the phase offset, and its value range is (0,1). Indicates phase error, This indicates the cancellation direction corresponding to the phase gradient adjustment, which is determined by the magnitude gradient and phase gradient of the phase offset value.

[0082] S70: Based on the adjustment amplitude gradient and the corresponding cancellation direction, the time-domain voltage value and phase offset value are subjected to independent disturbance cancellation processing to obtain the corresponding independent cancellation signal.

[0083] Specifically, based on adjusting the magnitude gradient and the corresponding cancellation direction, when the magnitude gradient is positive, the reduction is... Increase when the magnitude gradient is negative This allows for independent perturbation cancellation of the time-domain voltage value in the direction of decreasing residual energy, and sets an update limit for the time-domain voltage value, such as the updated value. 10.0, then set =10.0; Updated If <0.1, then a forced setting will be applied. =0.1; if 0.1≤ If ≤10.0, then Keep the original value.

[0084] Based on the adjusted phase gradient and the corresponding cancellation direction, the phase is normalized. The phase normalization expression is shown below: (27) in, This represents the final phase value obtained after phase normalization. It is used to ensure physical realizability, limit the PA gain range, and prevent phase overflow that could lead to control failure. Indicates based on phase gradient Analyze the phase gradient adjustment direction, and based on Update the phase to obtain the phase offset value.

[0085] The corresponding independent cancellation signal is obtained based on the final phase value and the updated time-domain voltage value.

[0086] S80: The electromagnetic cancellation shielding result of the independent cancellation signal is compared with the preset threshold of the residual field strength, and the time domain voltage value and phase offset value are cyclically adjusted according to the feedback comparison result to obtain dynamic closed-loop control data.

[0087] Specifically, the electromagnetic cancellation shielding result of the independent cancellation signal is compared with the preset threshold of the residual field strength periodically. Based on the feedback result, the time domain voltage value and phase offset value are cyclically adjusted to achieve dynamic closed-loop control and obtain the dynamic closed-loop control data of electromagnetic shielding.

[0088] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0089] In one embodiment, a dynamic electromagnetic shielding device for complex electromagnetic environments is provided, which corresponds one-to-one with the dynamic electromagnetic shielding methods for complex electromagnetic environments described in the above embodiments. For example... Figure 7 As shown, the dynamic electromagnetic shielding device includes an electric field probe, an interference source physical identification module, a dynamic tuning module, an active shielding drive circuit, a reconfigurable excitation coil system, and a feedback module. The electric field probe acquires voltage signals, and the interference source physical identification module identifies the type of interference source and calls the corresponding model. The dynamic tuning module adjusts the time-domain voltage value K and phase shift, thereby driving the active shielding drive circuit to generate a corresponding shielding cancellation magnetic field to excite the coil. Periodic residual field strength detection, combined with the feedback module, periodically updates the time-domain voltage value K and phase shift, achieving dynamic closed-loop control. Specifically, as... Figure 8 and Figure 9 As shown, the dynamic electromagnetic shielding device for complex electromagnetic environments includes: an electric field probe 4, a base 6, and a rigid metal shell 1 fixed on the base 6. A closed cavity is formed between the base 6 and the rigid metal shell 1. An oxide coating is provided on the side wall of the rigid metal shell 1 located in the closed cavity. The electric field probe 4 is fixed on the base 6 and located in the closed cavity. The electromagnetic shielding device also includes a curved shell covering the side of the rigid metal shell 1 away from the base 6. A waveguide ventilation plate 5 is provided on the rigid metal shell 1, connecting the curved shell and the closed cavity. The outlet of the waveguide ventilation plate 5 located in the closed cavity is covered with an inner conductive mesh 2, and the outlet of the waveguide ventilation plate 5 located in the curved shell is covered with an outer conductive mesh 3.

[0090] The rigid metal casing in this embodiment can resist some environmental radiation interference and also provide mechanical protection. The outer aluminum metal casing forms a Faraday cage, the inner active shielding layer has a ferrite coating and a cancellation coil, and the waveguide ventilation plate adopts a hexagonal honeycomb array. Combined with the waveguide ventilation hole design, it achieves a balance between passive electromagnetic isolation and heat dissipation.

[0091] Specific limitations regarding dynamic electromagnetic shielding devices for complex electromagnetic environments can be found in the above description of dynamic electromagnetic shielding methods for complex electromagnetic environments, and will not be repeated here. Each module in the aforementioned dynamic electromagnetic shielding device for complex electromagnetic environments can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of a computer device as software, so that the processor can call and execute the corresponding operations of each module.

[0092] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 10 As shown, the computer device includes a processor, memory, network interface, and database connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The database stores data related to dynamic electromagnetic shielding. The network interface communicates with external terminals via a network connection. When executed by the processor, the computer program implements a dynamic electromagnetic shielding method for complex electromagnetic environments.

[0093] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program being executed by a processor to implement the steps of a dynamic electromagnetic shielding method for complex electromagnetic environments.

[0094] Those skilled in the art will recognize that the units of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of the invention.

[0095] In the embodiments provided by the present invention, it should be understood that the division of units is only a logical functional division. In actual implementation, there may be other division methods, such as multiple units can be combined into one unit, one unit can be split into multiple units, or some features can be ignored.

[0096] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0097] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0098] 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 them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A dynamic electromagnetic shielding method for complex electromagnetic environments, characterized in that, The method includes: Acquire real-time voltage data under complex electromagnetic environments and perform voltage characteristic analysis, output the feature vector of the real-time voltage signal, and analyze the type of interference source of the current electric field based on the feature vector; Based on the type of interference source, the feature vector is subjected to time-series prediction of interference trend using a pre-trained LSTM model to obtain time-domain voltage value and phase shift value. The composite loss coefficient is calculated for the time-domain voltage value and the phase offset value, and the voltage interference signal is processed by reverse cancellation signal synthesis based on the calculated composite loss coefficient. Based on the synthesized reverse cancellation signal, the preset multi-coil array is dynamically activated to generate a directional cancellation magnetic field corresponding to the real-time electromagnetic interference, thereby electromagnetically cancelling and shielding the current electromagnetic interference.

2. The dynamic electromagnetic shielding method for complex electromagnetic environments according to claim 1, characterized in that, The method further includes: The residual field strength after electromagnetic cancellation and shielding is acquired in real time. When the residual field strength reaches a preset threshold, the time domain voltage value and the phase offset value are dynamically adjusted to generate the corresponding single adjustment result. Based on the single adjustment result, calculate the corresponding adjustment amplitude gradient of the time-domain voltage value and the phase offset value, and analyze the cancellation direction of the residual field strength; Based on the adjustment amplitude gradient and the corresponding cancellation direction, the time-domain voltage value and the phase offset value are subjected to independent disturbance cancellation processing to obtain the corresponding independent cancellation signal; The electromagnetic cancellation shielding result of the independent cancellation signal is compared with the preset threshold of the residual field strength, and the time-domain voltage value and the phase offset value are cyclically adjusted according to the feedback comparison result to obtain dynamic closed-loop control data.

3. The dynamic electromagnetic shielding method for complex electromagnetic environments according to claim 2, characterized in that, The real-time acquisition of the residual field strength after electromagnetic cancellation shielding, and the dynamic adjustment of the time-domain voltage value and the phase shift value when the residual field strength reaches a preset threshold, generating a corresponding single adjustment result, specifically includes the following: The voltage signal corresponding to the residual field strength is subjected to frequency domain transformation, and the main interference frequency is extracted. Each main interference frequency is then subjected to independent orthogonal adjustment, wherein the orthogonal adjustment expression is as follows: （1） （2） in, Indicates the first frequency band within the target frequency band. One main interference frequency; The projection component of each of the main interference frequencies is calculated, and the expression for the projection component is as follows: （3） （4） in, Indicates the first The in-phase projection components of the main interference frequencies Indicates the first The quadrature components of the main interference frequencies This represents a one-dimensional array obtained from storing voltage signals. =5ns; The amplitude error and phase error of the main interference frequency are calculated based on the projection components, and the relevant time-domain voltage value and phase offset value are dynamically adjusted to compensate for the deviation. The expression for the amplitude error is as follows: （5） The phase error expression is as follows: （6） in, , These represent the amplitude error value and the phase error value, respectively. Indicates the first The target residual amplitude at the main interference frequency.

4. The dynamic electromagnetic shielding method for complex electromagnetic environments according to claim 3, characterized in that, The process of calculating the adjustment amplitude gradient corresponding to the time-domain voltage value and the phase shift value based on the single adjustment result, and analyzing the direction of cancellation of the residual field strength, specifically includes: The disturbance amplitude parameter of the residual field strength is adjusted based on the single adjustment result, wherein the expression of the disturbance amplitude parameter is as follows: （7） in, Indicates the first Updated values ​​of the disturbance amplitude parameters for each main interference frequency. Indicates the first Initial values ​​of the disturbance amplitude parameters for each main interference frequency. Δk =0.01; The disturbance amplitude is adjusted according to the adjusted disturbance amplitude parameters at the corresponding main disturbance frequency, and the amplitude gradient corresponding to the time-domain voltage value is calculated. The expression for the amplitude gradient is as follows: （8） in, Indicates the disturbance parameters The magnitude gradient adjustment value corresponding to the change , Indicates the disturbance parameters The amplitude of the residual signal after the disturbance , This represents the residual signal amplitude before the disturbance. The perturbation phase parameter of the residual field strength is adjusted based on the single adjustment result, wherein the expression of the perturbation phase parameter is as follows: （9） in, Indicates the first Updated values ​​of the disturbance phase parameters for each main interference frequency. Indicates the first Initial values ​​of the disturbance phase parameters for each main interference frequency. =0.01; Based on the adjusted disturbance phase parameters, the corresponding main interference frequency is subjected to disturbance phase adjustment, and the phase gradient corresponding to the phase offset value is calculated, wherein the expression for the phase gradient is as follows: （10） in, Indicates the disturbance parameters The corresponding phase gradient adjustment value for the change , Indicates the disturbance parameters The phase of the residual signal after the disturbance. , This indicates the residual signal phase before any disturbance.

5. The dynamic electromagnetic shielding method for complex electromagnetic environments according to claim 4, characterized in that, After calculating the corresponding adjustment amplitude gradients for the time-domain voltage value and the phase shift value based on the single adjustment result, and analyzing the cancellation direction of the residual field strength, the method further includes: Based on the amplitude error and the corresponding cancellation direction, the time-domain voltage value after the deviation is cancelled is updated, and the expression for the updated time-domain voltage value is as follows: （11） in, This represents the updated time-domain voltage value parameter. Indicates the first Initial values ​​of the disturbance amplitude parameters for each main interference frequency. Indicates the first The amplitude update step size coefficient for each main interference frequency has a value range of (0,1). Indicates amplitude error. This indicates the cancellation direction corresponding to the amplitude gradient adjustment, determined by the amplitude gradient of the time-domain voltage value. Decide; Based on the phase error and the corresponding cancellation direction, the phase offset value after the offset deviation is updated. The expression for the updated phase offset value is as follows: （12） in, This represents the updated phase offset value. Indicates the first Initial values ​​of the disturbance phase parameters for each main interference frequency. Indicates the first The phase update step size coefficient for each main interference frequency ranges from (0,1). Indicates phase error, This indicates the cancellation direction corresponding to the phase gradient adjustment, which is determined by the magnitude gradient and phase gradient of the phase offset value.

6. The dynamic electromagnetic shielding method for complex electromagnetic environments according to claim 1, characterized in that, The process of acquiring real-time voltage data under complex electromagnetic environments, performing voltage feature analysis, outputting feature vectors of real-time voltage signals, and analyzing voltage feature analysis of interference source types in the current electric field based on feature vectors specifically includes: The harmonic distortion rate vector in the voltage characteristics is calculated using formula (13), and the expression for the harmonic distortion rate vector is as follows: （13） in, This represents the amplitude of the 50Hz fundamental frequency. Indicates the first Second harmonic amplitude ; The pulse rise time vector in the voltage characteristics is calculated using formula (14), and the expression for the pulse rise time vector is as follows: （14） in, This indicates the time it takes for the pulse to rise to 90% of its peak value. This indicates the time it takes for the pulse to rise to 10% of its peak value; The spectral entropy vector in the voltage characteristics is calculated using formula (15), and the expression for the spectral entropy vector is as follows: （15） in, Represents frequency Normalization, , This represents the frequency point amplitude obtained by performing a Fourier transform on the real-time voltage data. Indicates the number of frequency points sampled; The carrier offset variance vector in the voltage characteristics is calculated using formula (16), and the expression for the carrier offset variance vector is as follows: （16） in, express Instantaneous frequency within the time period This indicates the average frequency within a set time window.

7. The dynamic electromagnetic shielding method for complex electromagnetic environments according to claim 1, characterized in that, The calculation of the composite loss coefficient for the time-domain voltage value and the phase offset value, and the subsequent inverse cancellation signal synthesis processing of the voltage interference signal based on the calculated composite loss coefficient, specifically includes: The composite loss coefficient is calculated using formula (17), and the expression for the composite loss coefficient is as follows: （17） in, The time-domain voltage loss coefficient is represented by the following formula: （18） in, The phase offset loss coefficient is represented by the formula shown below: （19） in, , It is a constant. Indicates the first Predicted time-domain voltage values ​​at each voltage sampling point Indicates the first The true time-domain voltage value of each voltage sampling point Indicates the first Predicted phase of each voltage sampling point Indicates the first The true phase of each voltage sampling point; Based on the time-domain voltage value and the phase offset value, the waveform trend of the interfering electromagnetic wave is predicted to obtain the voltage interference prediction waveform; The time-domain voltage value and phase of the voltage interference signal are adjusted in reverse according to the composite loss coefficient, and the voltage interference prediction waveform is fitted in reverse to obtain the reverse cancellation signal synthesis result of the voltage interference signal.

8. The dynamic electromagnetic shielding method for complex electromagnetic environments according to claim 7, characterized in that, The process of adjusting the time-domain voltage value and phase of the voltage interference signal in reverse according to the composite loss coefficient, and performing reverse cancellation fitting on the predicted voltage interference waveform to obtain the reverse cancellation signal synthesis result of the voltage interference signal specifically includes: Formula (20) represents the inverse cancellation signal of the voltage interference prediction waveform. The voltage interference signal is fitted with the inverse cancellation signal, and Formula (20) is shown below: （20） in, Indicates the reverse cancellation signal. This represents the output signal after phase shift. This represents the time-domain voltage value obtained by adjusting the composite loss coefficient. This represents the reference signal obtained after phase adjustment. This indicates the phase obtained by adjusting the composite loss coefficient. Represents angular frequency. This indicates the sampling time of the voltage interference signal.

9. A dynamic electromagnetic shielding device for complex electromagnetic environments, characterized in that, The dynamic electromagnetic shielding device is applied to the dynamic electromagnetic shielding method for complex electromagnetic environments as described in any one of claims 1-8. The electromagnetic shielding device includes: an electric field probe, a base, and a rigid metal shell fixed on the base. A closed cavity is formed between the base and the rigid metal shell. An oxide coating is provided on the side wall of the rigid metal shell located in the closed cavity. The electric field probe is fixed on the base and located in the closed cavity. The electromagnetic shielding device also includes a curved shell covering the side of the rigid metal shell away from the base. A waveguide ventilation plate communicating with the curved shell and the closed cavity is provided on the rigid metal shell. Both outlets of the waveguide ventilation plate are covered with conductive mesh.

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