A method, system, device and medium for complex capacitance measurement under interference electric field

Abstract

This invention relates to a method, system, device, and medium for measuring complex capacitance under an interfering electric field. The method includes: acquiring the interfering electric field signal, input voltage signal, and input current signal at the current and next moments; calculating the initial value of the corresponding interfering signal based on the interfering electric field signal at the current and next moments and the initial coefficients of a digital filter; calculating the first and second mean square errors respectively; calculating the first and second gradient functions based on the first and second mean square errors and constructing a coefficient optimization cost function for the digital filter; iteratively solving the coefficient optimization cost function to obtain the optimized digital filter coefficients and calculating the optimal value of the interfering signal; calculating the clean signal based on the optimal value, the input voltage signal, and the input current signal at the current moment; and calculating the complex capacitance value based on the clean signal. Compared with the prior art, this invention overcomes the shortcomings of existing anti-electric field interference methods, such as low flexibility, weak versatility, and cumbersome parameter calculation.

Description

Technical Field

[0001] This invention relates to the field of dielectric measurement technology of materials, and in particular to a method, system, device and medium for measuring complex capacitance under an interfering electric field. Background Technology

[0002] In complex capacitance measurements in fields such as polymer materials, biomedicine, electronic engineering, and electrical engineering, the large impedance of the test piece results in extremely weak current signals that are easily distorted by external electric field interference, severely affecting the measurement results. Sources of on-site electric field interference are widespread, including power frequency interference fields generated by high-voltage transmission lines and high-power electrical equipment, multi-frequency interference fields emitted by nearby test equipment, and interference fields formed by static charges generated by friction. To address this interference problem, existing anti-electric field interference methods are mainly divided into hardware and software anti-interference methods. Hardware anti-interference methods, such as using Faraday cages and shielded cables, suffer from problems such as large space requirements on the experimental setup, poor wiring flexibility, and parasitic capacitance reducing high-frequency measurement accuracy. Traditional filter techniques are only suitable for scenarios where the signal and interference frequencies are well separated and the characteristics are stable; the filtering effect significantly decreases after the interference characteristics change. Software anti-interference methods, such as arithmetic mean filtering and median filtering, while convenient, have drawbacks such as smoothing out real signal fluctuations and limited applicability. Furthermore, existing mainstream methods generally suffer from large footprints and fixed parameters. Calculation parameters need to be reset for different interference sources, resulting in low flexibility, insufficient economy, weak versatility, and cumbersome parameter calculations. This makes them unsuitable for scenarios with diverse and variable interference sources in complex capacitance measurements. For methods like the adaptive filtering algorithm disclosed in Chinese patent application CN113676157A, it is only applicable to DC bias cancellation, limiting its application scenarios and failing to meet the needs of eliminating complex electric field interference in dielectric measurement. It adopts a traditional adaptive filtering approach, updating filtering parameters only based on current and past state variables, without considering the impact of future states on the mean square error, resulting in weak dynamics.

[0003] Therefore, the technical problem that needs to be solved is how to overcome the shortcomings of existing anti-electric field interference methods, such as low flexibility, weak versatility, and cumbersome parameter calculation, and provide a filtering scheme that can adapt to different frequencies and types of electric field interference to achieve more accurate complex capacitance measurement. Summary of the Invention

[0004] The purpose of this invention is to overcome the problems of weak anti-electric field interference capability, insufficient universality of anti-interference methods, poor economy, and large footprint of the existing technology, and to provide a method, system, device and medium for measuring complex capacitance under interfering electric field.

[0005] The objective of this invention can be achieved through the following technical solutions: According to a first aspect of the present invention, a method for measuring complex capacitance under an interfering electric field is provided, the method comprising: The system acquires the interference electric field signal, input voltage signal, and input current signal at the current and next time moments. Based on the interference electric field signal at the current and next time moments and the initial coefficients of the digital filter, it calculates the initial value of the corresponding interference signal. The interference signal includes the interference voltage signal and the interference current signal. The first and second mean square errors are calculated based on the input current signal, input voltage signal and interference signal at the current time and the next time, respectively. The first and second gradient functions are calculated based on the first and second mean square errors, respectively. The coefficient optimization cost function of the digital filter is constructed based on the first and second gradient functions. The coefficient optimization cost function is iteratively solved to obtain the optimized digital filter coefficients. The optimal value of the interference signal is calculated based on the optimized digital filter coefficients. The clean signal is calculated based on the optimal value, the current input voltage signal, and the input current signal. The complex capacitance value is calculated based on the clean signal.

[0006] As a preferred technical solution, the method for obtaining the interference electric field signal, input voltage signal, and input current signal at the next moment is as follows: At the current moment, interference electric field signals, input voltage signals, and input current signals are collected from multiple consecutive historical moments. Based on the collected interference electric field signal, input voltage signal, and input current signal at the current moment, as well as the interference electric field signal, input voltage signal, and input current signal at multiple consecutive historical moments, the data is processed using the second-order Lagrange extrapolation formula, including: To obtain the interference electric field signal at the next moment, we have: ; in, Indicates the first Interference electric field signal at any given moment; Indicates the first Interference electric field signal at any given moment; Indicates the first Historical interference electric field signals at any given time; Indicates the first Historical interference electric field signals at any given time; To obtain the historical input voltage signal at the next moment, we have: ; in, Indicates the first The input voltage signal at any given time; Indicates the first The input voltage signal at any given time; Indicates the first Historical input voltage signal at any given time; Indicates the first Historical input voltage signal at any given time; To obtain the input current signal at the next moment, we have: ; in, Indicates the first The input current signal at any given time; Indicates the first The input current signal at any given time; Indicates the first Historical input current signal at any given time; Indicates the first Historical input current signal at any given time.

[0007] As a preferred technical solution, the method for calculating the interference signal is as follows: The method for calculating the interference signal at the current moment is as follows: ; ; The method for calculating the interference signal at the next moment is as follows: ; ; in, and They represent the first and Interference voltage signal at any given moment; and They represent the first time. Time and the Time-of-flight digital filter order; The first digital voltage filter One coefficient; and They represent the first and The electric field signal at a given moment; and Indicates the first and Interference current signal at any given moment; The digital current filter represents the first Each coefficient.

[0008] As a preferred technical solution, the cost function is: ; ; in, Represents the voltage cost function; Represents the current cost function; as well as Representing voltage and current on the 1st... The target reference gradient at time step; and These represent the voltage and current at the current moment, respectively. The target reference gradient; and These represent the voltage and current at the current moment, respectively. The first gradient function; and Representing voltage and current on the 1st... The second gradient function at time t is given by: ; ; ; ; and These represent the mean square error of the first voltage, respectively. Second voltage mean square error For the digital voltage filter coefficients The partial derivatives; Indicates transpose; and These represent the mean square error of the first current, respectively. Second current mean square error For the digital current filter coefficients The partial derivatives; Indicates the first error and The sequence length; Indicates the second error and The sequence length.

[0009] According to a second aspect of the present invention, a complex capacitance measurement system under an interfering electric field is provided, the system comprising: The data acquisition and processing module is used to acquire the interference electric field signal, input voltage signal, and input current signal at the current and next moments. The coefficient optimization module performs the following steps to obtain the optimal coefficients of the digital filter: Based on the interference electric field signal at the current time and the initial coefficients of the digital filter, calculate the initial value of the corresponding interference signal; The first and second mean square errors are calculated based on the input current signal, input voltage signal and interference signal at the current time and the next time, respectively. The first and second gradient functions are calculated based on the first and second mean square errors, respectively. The optimized digital filter coefficients are obtained by iteratively solving the coefficient optimization cost function of the digital filter constructed based on the first and second gradient functions. The complex capacitance value calculation module calculates the optimal value of the interference signal based on the optimized digital filter coefficients, calculates the clean signal based on the optimal value, the current input voltage signal, and the input current signal, and calculates the complex capacitance value based on the clean signal.

[0010] According to a third aspect of the present invention, an electronic device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the program to implement the method described thereon.

[0011] According to a fourth aspect of the present invention, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the method described thereon.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1) Addressing the shortcomings of existing technologies, such as smoothing signal fluctuations and limited applicability, this invention collects target voltage signals, current signals, and their associated interference electric field signals. The interference electric field signals associated with the target voltage and current signals are processed by a digital filter, subtracted from the target waveform, and parameters are adjusted to cancel the interference and obtain a clean signal. Furthermore, the historical signals collected in this invention predict the signal at the next moment using a second-order Lagrange extrapolation formula. This allows for the prediction of interference electric field signals, learning interference characteristics to accurately distinguish between interference and the real signal, and avoiding indiscriminate smoothing. The extrapolation formula compensates for the shortcomings of traditional adaptive filtering, which only considers the current and past states. Ultimately, it can effectively preserve the real signal characteristics, adapt to diverse and variable interference scenarios, and meet the needs of complex electric field interference elimination in the field of dielectric measurement.

[0013] 2) To address the shortcomings of existing technologies, such as limited application scenarios and inability to meet the requirements for eliminating complex electric field interference in the field of dielectric measurement, this invention captures complex interference characteristics by collecting interference electric field signals to overcome the limitation of only being able to cancel DC bias; the extrapolation formula is adapted to complex interference scenarios, and the influence of future states on the mean square error is introduced to improve stability; the pure signal model accurately separates the signal and interference to adapt to the core requirements of dielectric measurement, ultimately breaking the limitation of limited application scenarios, eliminating various complex electric field interferences in the field of dielectric measurement, adapting to complex capacitance measurement scenarios and meeting the requirements for accurate measurement.

[0014] 3) This invention uses digital algorithms to replace physical filtering. It can update parameters by modifying the program, save space and reduce costs. The iterative algorithm realizes automatic optimization of coefficients without the need for tedious manual calculations. The correlation characteristics between the interference electric field signal and the input voltage and current signals realize interference adaptive adaptation. In the end, it greatly reduces the footprint and reduces hardware costs. Parameter optimization is convenient and easy to operate, significantly improving flexibility and versatility, and solving the problem of fixed parameters in traditional methods. Attached Figure Description

[0015] Figure 1 This is a flowchart of the method of the present invention; Figure 2 This is a flowchart of the algorithm of the present invention; Figure 3 This is a schematic diagram of the complex capacitance measurement method under interference electric field of the present invention; Figure 4 This is the test circuit topology diagram of the present invention; Figure 5 This is a voltage waveform diagram under an interference-free electric field according to the present invention; Figure 6 This is a current waveform diagram under an interference-free electric field according to the present invention; Figure 7 This is a graph showing the complex capacitance value under interference-free conditions according to the present invention; Figure 8 The voltage waveform diagram of the present invention in the presence of an interfering electric field; Figure 9 The current waveform diagram of the present invention is shown in the presence of an interfering electric field; Figure 10 This is a graph showing the complex capacitance value under the presence of an interfering electric field, as described in this invention. Figure 11 This is a pure voltage waveform diagram of the present invention; Figure 12 This is a pure current waveform diagram of the present invention; Figure 13 This is a graph of the complex capacitance value measured based on the method provided in this invention. Detailed Implementation

[0016] 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 should fall within the scope of protection of the present invention.

[0017] Example 1 To address the problems existing in the prior art, this invention provides a method for measuring complex capacitance under an interfering electric field, the process of which is as follows: Figure 1 As shown, relying on Figure 2 The look-ahead adaptive filtering algorithm shown suppresses external interference electric fields, thereby achieving more accurate complex capacitance measurements. Details include: S1. Obtain the interference electric field signal, input voltage signal, and input current signal at the current and next time moments. Based on the interference electric field signal at the current and next time moments and the initial coefficients of the digital filter, calculate the initial value of the corresponding interference signal.

[0018] S11. Collect the interference electric field signal, input voltage signal and input current signal at the current moment.

[0019] based on Figure 3 The test schematic diagram shown is used to collect detailed data on the power supply and interference electric field applied to the circuit module under test 200 by the amplitude and frequency adjustable power supply 206 and the interference electric field 107. The interference electric field signal at the current moment is measured by electric field sensor V2, voltage sensor V1, and current sensor A1, respectively. Input voltage signal and input current signal .

[0020] Among them, the input voltage signal and input current signal respectively and This indicates that both are composed of pure signals. and and the corresponding interference signals and Superimposed; and for interference signals and Both are caused by interfering electric fields This is triggered by interference with the electric field signal. Originating from the same interference source, therefore and There is a high correlation. and There is also a high correlation.

[0021] And in Figure 3 The drawn test circuit topology diagram also includes a look-ahead adaptive filtering algorithm module 204 and a complex capacitance calculation module 205. A detailed topology diagram of the circuit under test module 200 is shown below. Figure 4 As shown, it includes a first resistor 101, a first capacitor 102, a second resistor 103, a third resistor 104, a second capacitor 105, and a third capacitor 106.

[0022] S12. Obtain the interference electric field signal, input voltage signal, and input current signal at the next moment.

[0023] S121. At the current moment, collect interference electric field signals, input voltage signals, and input current signals from multiple consecutive historical moments.

[0024] S122. Based on the interference electric field signal, input voltage signal, and input current signal collected at the current moment, as well as the interference electric field signal, input voltage signal, and input current signal at multiple consecutive historical moments, the signals are processed using the second-order Lagrange extrapolation formula.

[0025] In detail, to obtain the interference electric field signal at the next moment, we have: ; in, Indicates the first Interference electric field signal at any given moment; Indicates the first Interference electric field signal at any given moment; Indicates the first Historical interference electric field signals at any given time; Indicates the first Historical interference electric field signals at any given time.

[0026] To obtain the historical input voltage signal at the next moment, we have: ; in, Indicates the first The input voltage signal at any given time; Indicates the first The input voltage signal at any given time; Indicates the first Historical input voltage signal at any given time; Indicates the first Historical input voltage signal at any given time.

[0027] To obtain the input current signal at the next moment, we have: ; in, Indicates the first The input current signal at any given time; Indicates the first The input current signal at any given time; Indicates the first Historical input current signal at any given time; Indicates the first Historical input current signal at any given time.

[0028] S13. Calculate the interference signal.

[0029] Due to interference signals from electric fields, voltages, and currents in practice , and Coming from the same source of interference, the three have an inherent, learnable correlation, namely: 1) Homology: , and 1) From the same interfering signal source; 2) Strong correlation: , and The waveform changes are similar.

[0030] Based on the above properties, a parameter-tunable digital filter is introduced for processing. Specifically, the parameter-tunable digital filter can adjust its own parameters, such as weighting, delay, and combination, from... Extract from respectively with and Due to their similar characteristics, they share a common origin and strong correlation. By continuously iterating and updating the adjustable digital filter coefficients, the interference components in the calibration signal are adaptively canceled, eliminating their influence. When the interference components are eliminated, the difference between the input voltage and current signals and the interference signals obtained by the adjustable digital filter is the desired pure voltage and current signals.

[0031] For the reasons mentioned above, it is necessary to process the interference electric field signal using a digital filter to calculate the impact of the interference electric field on voltage and current, i.e., the interference voltage signal and interference current signal. The corresponding method is as follows: The method for calculating the interference signal at the current moment is as follows: ; ; The method for calculating the interference signal at the next moment is as follows: ; ; in, and They represent the first and Interference voltage signal at any given moment; and They represent the first time. Time and the The order of the digital filter at time step; The first digital voltage filter One coefficient; and They represent the first and The electric field signal at a given moment; and Indicates the first and Interference current signal at any given moment; The digital current filter represents the first Each coefficient.

[0032] S2. Calculate the first and second mean square errors based on the input current signal, input voltage signal and interference signal at the current time and the next time respectively. Calculate the first and second gradient functions based on the first and second mean square errors respectively. Construct the coefficient optimization cost function of the digital filter based on the first and second gradient functions.

[0033] S21. Calculate the first and second mean square errors.

[0034] S211. Construct a pure signal calculation model, using the first... For example, time: ; ; Indicates the first The voltage error at any given time, i.e., the pure voltage signal; Indicates the first The input voltage signal at any given time; Indicates the first The interference voltage signal obtained at each moment; Indicates the first The current error at any given time, i.e., the pure current signal; Indicates the first The input current signal at any given time; Indicates the first The interference current signal obtained at any time.

[0035] S212. Based on the error calculated above, calculate the first mean square error and the second mean square error.

[0036] Based on the The first mean square error of the voltage and current errors at time points is calculated using the following formula: ; ; Indicates the first The length of the pure signal at any given moment; Indicating the first pure voltage signal One value; This represents the mean of the pure voltage signal; Indicating the first pure current signal One value; This represents the mean value of the pure current signal.

[0037] Based on the The first mean square error of the voltage and current errors at time points is calculated using the following formula: ; ; Indicates the first The length of the pure signal at any given moment; Indicating the first pure voltage signal One value; This represents the mean of the pure voltage signal; Indicating the first pure current signal One value; This represents the mean value of the pure current signal.

[0038] S22. Calculate the first and second gradient functions based on the first and second mean square errors, respectively.

[0039] Wherein, the first gradient function refers to the function at the 1st... At time t, the result is calculated based on the first mean square error, as detailed below: ; ; The second gradient function refers to the function at the second... At time t, the result is calculated based on the second mean square error, as detailed below: ; ; and These represent the mean square error of the first voltage, respectively. Second voltage mean square error For the digital voltage filter coefficients The partial derivatives; Indicates transpose; and These represent the mean square error of the first current, respectively. Second current mean square error For the digital current filter coefficients The partial derivatives; Indicates the first error and The sequence length; Indicates the second error and The sequence length.

[0040] S23. Construct the cost function.

[0041] Since the goal of optimization is to minimize the gradient function, and the minimum value of the gradient function is the point where the slope is 0, the cost function can be constructed as follows: ; ; in, Represents the voltage cost function; Represents the current cost function; as well as Representing voltage and current on the 1st... The target reference gradient at time step; and These represent the voltage and current at the current moment, respectively. The target reference gradient; and These represent the voltage and current at the current moment, respectively. The first gradient function; and Representing voltage and current on the 1st... The second gradient function at time t.

[0042] That is, the closer the cost function is to 0, the better, and a weight allocation is required in this process. and The initial coefficients are all 1, indicating that the current and future times have the same weight ratio, meaning that the current and future times have the same impact on the cost function. When the future time is the primary factor, this can be addressed by increasing... The weighting coefficients before the adjustment are weighted accordingly.

[0043] S3. Iteratively solve the coefficient optimization cost function to obtain the optimized digital filter coefficients. Calculate the optimal value of the interference signal based on the optimized digital filter coefficients. Calculate the clean signal based on the optimal value, the current input voltage signal, and the input current signal. Calculate the complex capacitance value based on the clean signal.

[0044] S31. Iteratively solve the coefficient optimization cost function.

[0045] In this embodiment, the whale algorithm is selected to iteratively solve the cost function. The detailed process is as follows: S311. Initialize WOA and set the maximum number of iterations. Number of individuals Spiral shape parameters b = l =1.

[0046] 312. Calculation parameters A , C, pThe value of the equals is used to calculate the cost function at the current number of iterations. J Minimum optimal individual .

[0047] S313, according to A, p The value determines which of three actions each individual can take: surround the prey, bubble web attack, or random search.

[0048] S314. Determine if the maximum number of iterations has been reached. If so, output the optimal individual. The value is used as a parameter for an adjustable digital filter. Find the optimal solution for the parameters; otherwise, repeat steps S312 to S314.

[0049] S32. Calculate the optimal value of the interference signal.

[0050] The optimal value of the interference signal is calculated based on the following formula: ; ; in, The first factor representing the optimal coefficients of the digital voltage filter. One value; The first factor representing the optimal coefficients of the digital current filter Values.

[0051] S33. Calculate the clean signal.

[0052] ; ; in, and These are the final pure voltage and current values.

[0053] S33. Calculate the complex capacitance value.

[0054] ; Indicates the value of the complex capacitance; A phasor representing the pure voltage; A phasor representing pure current; Represents the imaginary unit; This indicates the frequency of the applied alternating electric field.

[0055] Furthermore, this embodiment also provides a complex capacitance measurement system under an interfering electric field to implement the above-mentioned method. The system includes: 1) a data acquisition and processing module, used to acquire the interfering electric field signal, input voltage signal, and input current signal at the current and next time moments. 2) a coefficient optimization module, which performs the following steps to obtain the optimal coefficients of the digital filter: calculating the initial value of the corresponding interfering signal based on the interfering electric field signal at the current and next time moments and the initial coefficients of the digital filter; calculating the first and second mean square errors based on the input current signal, input voltage signal, and interfering signal at the current and next time moments respectively; calculating the first and second gradient functions based on the first and second mean square errors respectively; iteratively solving the coefficient optimization cost function of the digital filter constructed based on the first and second gradient functions to obtain the optimized digital filter coefficients. 3) a complex capacitance value calculation module, which calculates the optimal value of the interfering signal based on the optimized digital filter coefficients; calculates the clean signal based on the optimal value, the input voltage signal, and the input current signal at the current time; and calculates the complex capacitance value based on the clean signal.

[0056] Example 2 To verify the feasibility of the methods provided in the above embodiments, this embodiment further... Figure 3 and Figure 4 The circuit shown is measured as a topological object, and its connection method is as follows: Figure 4 middle First resistor 101 and The first capacitor 102 is connected in parallel. The second resistor 103 and The second capacitor 105 is connected in series and is denoted as... , The third resistor 104 and The third capacitor, 106, is connected in series and denoted as... ,Will , and First resistor 101 and The first capacitor 102 is connected in parallel; the interference electric field 107 is mainly used to apply the interference electric field and is located 0.3m from the main circuit.

[0057] The first branch unit is selected (Accuracy 1%, temperature coefficient 5ppm / ℃) (Polystyrene medium); the second branch unit is selected , Among them, capacitor Polystyrene dielectric is used; equivalent parallel capacitance Furthermore, it uses polystyrene dielectric and has an equivalent parallel resistance. .

[0058] By using sensors to synchronously acquire signals from the main circuit and interfering electric fields, the waveforms of the input voltage and input current when no interfering electric field is applied can be obtained, such as... Figure 5 and Figure 6 As shown, and in this case, the measured complex capacitance value is as follows: Figure 7 As shown, Figure 7 The solid line represents the real part of the complex capacitance value, and the dashed line represents the imaginary part. By turning on the electric field generator, applying an interference electric field, and adjusting the frequency converter 206 to excite the circuit module under test, the following result can be obtained: Figure 8 and Figure 9 The voltage and current waveforms are shown, and the complex capacitance value is measured as follows. Figure 10 As shown, the complex capacitance curve shifts due to the influence of the interfering electric field compared to the interference-free environment.

[0059] Based on this, the filtering process is performed using the technical solution provided by this invention to obtain the following result: Figure 11 and Figure 12 The voltage and current waveforms shown are used to determine the complex capacitance value based on the filtered voltage and current. Figure 13 As shown, the interference signal has been effectively suppressed in this waveform, and the voltage waveform obtained after filtering is similar to... Figure 5 The uninterrupted waveform shown is highly similar to the current waveform obtained after filtering. Figure 6 The waveform without interference shown is highly similar to the measured complex capacitance value. Figure 7 They are also highly similar, thus ensuring more accurate complex capacitance measurements.

[0060] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method of complex capacitance measurement in the presence of an interfering electric field, characterized by, The method includes: The system acquires the interference electric field signal, input voltage signal, and input current signal at the current and next time moments. Based on the interference electric field signal at the current and next time moments and the initial coefficients of the digital filter, it calculates the initial value of the corresponding interference signal. The interference signal includes the interference voltage signal and the interference current signal. The first and second mean square errors are calculated based on the input current signal, input voltage signal and interference signal at the current time and the next time, respectively. The first and second gradient functions are calculated based on the first and second mean square errors, respectively. The coefficient optimization cost function of the digital filter is constructed based on the first and second gradient functions. The coefficient optimization cost function is iteratively solved to obtain the optimized digital filter coefficients. The optimal value of the interference signal is calculated based on the optimized digital filter coefficients. The clean signal is calculated based on the optimal value, the current input voltage signal, and the input current signal. The complex capacitance value is calculated based on the clean signal.

2. The method of claim 1, wherein, The method for obtaining the interference electric field signal, input voltage signal, and input current signal at the next moment is as follows: At the current moment, interference electric field signals, input voltage signals, and input current signals are collected from multiple consecutive historical moments. Based on the collected interference electric field signal, input voltage signal, and input current signal at the current moment, as well as the interference electric field signal, input voltage signal, and input current signal at multiple consecutive historical moments, the data is processed using the second-order Lagrange extrapolation formula, including: To obtain the interference electric field signal at the next moment, we have: ； wherein, represents the interference electric field signal at the time point; represents the interference electric field signal at the time point; represents the historical interference electric field signal at the time point; represents the historical interference electric field signal at the time point; To obtain the historical input voltage signal at the next moment, we have: ； in, Indicates the first The input voltage signal at any given time; Indicates the first The input voltage signal at any given time; Indicates the first Historical input voltage signal at any given time; Indicates the first Historical input voltage signal at any given time; To obtain the input current signal at the next moment, we have: ； in, Indicates the first The input current signal at any given time; Indicates the first The input current signal at any given time; Indicates the first Historical input current signal at any given time; Indicates the first Historical input current signal at any given time.

3. The method for measuring complex capacitance under an interfering electric field according to claim 1, characterized in that, The method for calculating the interference signal is as follows: The method for calculating the interference signal at the current moment is as follows: ； ； The method for calculating the interference signal at the next moment is as follows: ； ； in, and They represent the first and Interference voltage signal at any given moment; and They represent the first time. Time and the The order of the digital filter at time step; The first digital voltage filter One coefficient; and They represent the first and The electric field signal at a given moment; and Indicates the first and Interference current signal at any given moment; The digital current filter represents the first Each coefficient.

4. The method for measuring complex capacitance under an interfering electric field according to claim 1, characterized in that, The cost function is as follows: ； ； in, Represents the voltage cost function; Represents the current cost function; as well as Representing voltage and current on the 1st... The target reference gradient at time step; and These represent the voltage and current at the current moment, respectively. The target reference gradient; and These represent the voltage and current at the current moment, respectively. The first gradient function; and Representing voltage and current on the 1st... The second gradient function at time t is given by: ； ； ； ； and These represent the mean square error of the first voltage, respectively. Second voltage mean square error For the digital voltage filter coefficients The partial derivatives; Indicates transpose; and These represent the mean square error of the first current, respectively. Second current mean square error For the digital current filter coefficients The partial derivatives; Indicates the first error and The sequence length; Indicates the second error and The sequence length.

5. A complex capacitance measurement system under an interfering electric field, characterized in that, The system includes: The data acquisition and processing module is used to acquire the interference electric field signal, input voltage signal, and input current signal at the current and next moments. The coefficient optimization module performs the following steps to obtain the optimal coefficients of the digital filter: Based on the interference electric field signal at the current time and the initial coefficients of the digital filter, calculate the initial value of the corresponding interference signal; The first and second mean square errors are calculated based on the input current signal, input voltage signal and interference signal at the current time and the next time, respectively. The first and second gradient functions are calculated based on the first and second mean square errors, respectively. The optimized digital filter coefficients are obtained by iteratively solving the coefficient optimization cost function of the digital filter constructed based on the first and second gradient functions. The complex capacitance value calculation module calculates the optimal value of the interference signal based on the optimized digital filter coefficients, calculates the clean signal based on the optimal value, the current input voltage signal, and the input current signal, and calculates the complex capacitance value based on the clean signal.

6. The complex capacitance measurement system under an interfering electric field according to claim 5, characterized in that, The data acquisition and processing module performs the following steps to obtain the interference electric field signal, input voltage signal, and input current signal at the next moment: Based on the collected interference electric field signal, input voltage signal, and input current signal at the current moment, processing is performed using the second-order Lagrange extrapolation formula, including: To obtain the interference electric field signal at the next moment, we have: ； in, Indicates the first Interference electric field signal at any given moment; Indicates the first Interference electric field signal at any given moment; Indicates the first Historical interference electric field signals at any given time; Indicates the first Historical interference electric field signals at any given time; To obtain the historical input voltage signal at the next moment, we have: ； in, Indicates the first The input voltage signal at any given time; Indicates the first Historical input voltage signal at any given time; Indicates the first Historical input voltage signal at any given time; Indicates the first Historical input voltage signal at any given time; To obtain the input current signal at the next moment, we have: ； in, Indicates the first The input current signal at any given time; Indicates the first The input current signal at any given time; Indicates the first Historical input current signal at any given time; Indicates the first Historical input current signal at any given time.

7. The complex capacitance measurement system under an interfering electric field according to claim 5, characterized in that, The coefficient optimization module performs the following steps to calculate the interference signal: The method for calculating the interference signal at the current moment is as follows: ； ； The method for calculating the interference signal at the next moment is as follows: ； ； in, and They represent the first and Interference voltage signal at any given moment; and They represent the first time. Time and the The order of the digital filter at time step; The first digital voltage filter One coefficient; and They represent the first and The electric field signal at a given moment; and Indicates the first and Interference current signal at any given moment; The digital current filter represents the first Each coefficient.

8. The complex capacitance measurement system under an interfering electric field according to claim 5, characterized in that, The cost function is as follows: ； ； in, Represents the voltage cost function; Represents the current cost function; as well as Representing voltage and current on the 1st... The target reference gradient at time step; and These represent the voltage and current at the current moment, respectively. The target reference gradient; and These represent the voltage and current at the current moment, respectively. The first gradient function; and Representing voltage and current on the 1st... The second gradient function at time t is given by: ； ； ； ； and These represent the first mean square error, respectively. Second voltage mean square error For the digital voltage filter coefficients The partial derivatives; Indicates transpose; and These represent the mean square error of the first current, respectively. Second current mean square error For the digital current filter coefficients The partial derivatives; Indicates the first error and The sequence length; Indicates the second error and The sequence length.

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 program, it implements the method as described in any one of claims 1 to 4.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method as described in any one of claims 1 to 4.

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