Electric leakage monitoring and protection method and system for mass spectrometer high-voltage power supply

Abstract

The invention relates to the technical field of electric leakage monitoring and protection, and particularly discloses an electric leakage monitoring and protection method and system for a mass spectrometer high-voltage power supply, a layer of gold nanorod array film is embedded in a mass spectrometer high-voltage power supply electrode vacuum coating layer, and a group of gold nanorod arrays are arranged near a mass spectrometer high-voltage power supply output electrode. Detecting a micro-area electric field on the surface of an electrode corresponding to a mass spectrometer high-voltage power supply by utilizing a plasma resonance effect of a local surface of the gold nanorod array; therefore, a real-time electric field distortion signal with a high signal-to-noise ratio is obtained; further predicting an electric leakage evaluation coefficient of each future time point; when the electric leakage evaluation coefficient at a certain future time point is about to reach a set threshold coefficient, the system triggers a protection mechanism in advance and cuts off the output of the high-voltage power supply within millisecond-level time, so that the safety and reliability of the high-voltage power supply of the mass spectrometer can be remarkably improved, and a solid foundation is provided for the safe operation of a high-precision analysis instrument.

Description

Technical Field

[0001] The invention belongs to the technical field of leakage monitoring and protection, and relates to a leakage monitoring and protection method and system for a high-voltage power supply of a mass spectrometer. Background Art

[0002] As a high-precision analytical instrument, mass spectrometer is widely used in life science, environmental monitoring, material analysis and other fields. Its core component, high-voltage power supply, usually operates in the voltage range of several thousand volts or even higher. Once leakage occurs, it may not only cause damage to the internal circuit or components of the equipment, but may even cause safety accidents such as high-voltage discharge and short circuit, posing a threat to the life safety of operators. Secondly, leakage is often an early sign of equipment aging, dielectric breakdown or increased environmental humidity. By real-time monitoring of the leakage status of the high-voltage power supply, potential hidden dangers can be discovered in time to avoid sudden failure of the equipment during operation, thereby reducing downtime and maintenance costs.

[0003] However, current technology still has many technical defects and drawbacks in the leakage monitoring of high-voltage power supplies for mass spectrometers. First, most traditional leakage monitoring methods rely on direct measurement of leakage current, and this method usually requires direct coupling of the monitoring circuit with the high-voltage power supply, which poses a great safety risk. Especially in high-voltage environments, the measuring equipment itself may be damaged by high-voltage shocks, or even cause more serious electrical accidents. Secondly, existing technologies mostly use a single current or voltage monitoring indicator, lack the ability to fully perceive changes in the spatial distribution of the electric field, and are unable to accurately locate the specific area where the leakage occurs or predict the trend of the leakage, resulting in a large lag and blindness in the handling of leakage problems. Summary of the invention

[0004] In view of the above problems existing in the prior art, the present invention provides a leakage monitoring and protection method and system for a high voltage power supply of a mass spectrometer, which are used to solve the above technical problems.

[0005] In order to achieve the above purpose and other purposes, the technical solution adopted by the present invention is as follows: In one aspect, the present invention provides a method for monitoring and protecting leakage of a high voltage power supply of a mass spectrometer, the method comprising the following steps: A layer of gold nanorod array film is embedded in the vacuum coating layer of the high-voltage power supply electrode of the mass spectrometer, and a group of gold nanorod arrays are arranged near the output electrode of the high-voltage power supply of the mass spectrometer. The plasma resonance effect of the local surface of the gold nanorod array is used to detect the micro-area electric field on the surface of the corresponding electrode of the high-voltage power supply of the mass spectrometer; When a change in the electric field in a micro-area is detected, the light source is modulated to emit a laser of a specific wavelength, thereby capturing the real-time electric field distortion signal; a dual-frequency lock-in amplifier is used to extract the specific harmonic components of the real-time electric field distortion signal, thereby obtaining a real-time electric field distortion signal with a high signal-to-noise ratio; Based on the real-time electric field distortion signal with high signal-to-noise ratio, the leakage assessment coefficient at each future time point is predicted; when the leakage assessment coefficient at a certain future time point is about to reach the set threshold coefficient, the system triggers the protection mechanism in advance within milliseconds and cuts off the high-voltage power supply output.

[0006] When a change in the electric field in the micro area is detected, the implementation logic is: Collect the LSPR resonance wavelength of the gold nanorod array, record the initial wavelength λ0 and the wavelength λ at the current time point, calculate the difference between the wavelength λ at the current time point and the initial wavelength λ0, and obtain the wavelength offset △λ at the current time point; The wavelength shift △λ at the current time point is integrated with the wavelength shifts at previous time points, and the time derivatives of all time points are calculated to obtain the wavelength shift rate λ' at all time points; Obtaining experimentally calibrated sensitivity of gold nanorod arrays to changes in local electric fields , the dielectric constant of the coating layer ε and the dielectric constant of the vacuum ε0, and the static electric field distortion in the micro-area electric field is calculated respectively and dynamic electric field distortion ; The static electric field distortion α1 and the dynamic electric field distortion α2 in the micro-area electric field are summed to obtain the total electric field distortion in the micro-area electric field. Compare the total electric field distortion in the micro-area electric field with the set distortion threshold: If the former is greater than the latter, it is determined that the electric field in the micro-region has changed; Otherwise, it is determined that the electric field in the micro-region has not changed.

[0007] By modulating the light source to emit laser of a specific wavelength, the logic is as follows: Extracting Plasmon Frequencies of Gold Nanorod Materials from the Gold Nanorod Database , and then calculate the intrinsic plasma wavelength of the gold nanorod material , where c is the speed of light; Simultaneous calculation of the equivalent dielectric constant of the dielectric layer surrounding the gold nanorods ,in represent the refractive index and thickness of the silicon dioxide layer in the dielectric layer surrounding the gold nanorods, respectively; represent the refractive index and thickness of the tantalum pentoxide layer in the dielectric layer around the gold nanorods, is the total thickness of the dielectric layer; The real part of the dielectric parameter ε1 of the gold nanorod material in the optical frequency band is calculated based on the Drude model, so as to calculate the optimal incident laser wavelength for exciting the LSPR effect of the gold nanorod array. , where Γ is the plasma frequency correction value caused by the finite size of the gold nanorods, , R is the aspect ratio of the gold nanorod, R=L / D, L and D represent the length and diameter of the gold nanorod, respectively; P is the depolarization factor, which represents the correction value of the gold nanorod geometry to the electric field distribution, .

[0008] Obtain real-time electric field distortion signals with high signal-to-noise ratio, including: The real-time electric field distortion signal is assumed to consist of the distortion signal and the environmental noise: , is the amplitude of the distorted signal, is the frequency of the distorted signal, is the initial phase of the distorted signal, is the environmental noise signal; A sine wave with a base frequency of f1 = 1 kHz and a sub-frequency of f2 = 2.5 kHz is selected as the laser modulation signal. Two sinusoidal reference signals are generated by dual-frequency modulation of the laser of the modulated light source: ; The real-time electric field distortion signal Mixed with two sinusoidal reference signals respectively, two mixed signals are obtained: ; Perform low-pass filtering on the mixed signals V1 and V2 to remove the high-frequency components and retain only the frequency and The signal: ; The low-pass filtered signals V1' and V2' are phase-weighted and summed to obtain the final real-time electric field distortion signal with high signal-to-noise ratio. .

[0009] Predict leakage assessment coefficients at various future time points, including: The total electric field distortion in the micro-area electric field at M consecutive historical time points is collected to form a total electric field distortion sequence: , △τ is the historical data sampling interval, M is the historical data window length, t is the current time point, and α is the total electric field distortion in the micro-area electric field; The time decay weight of each historical time point is calculated from this , e is a natural constant, ρ is a decay rate constant, which is determined by fitting the autocorrelation function of historical data, j is the reverse index of the historical time point, j=1 represents the most recent moment, and j=M represents the earliest moment; The current time point is recorded as t, and each future time point is defined as , where i is the number of each future time point, i=1,2,...N, N is the total number of future time points, is the time interval difference between each future time point and the current time point; The leakage assessment coefficient at each future time point is calculated from this Where η1 is the contribution weight of historical electric field distortion data, , They respectively represent the fluctuation degree of the electric field distortion signal and the fluctuation degree of the system noise within the length of the historical data window; η2 is the sensitivity coefficient of the electric field change rate, γ is the time inertia of the leakage development process, exp(·) represents the exponential function with the natural number e as the base, is the total electric field distortion in the micro-area electric field at the jth historical time point, is the distortion change rate at each future time point in the micro-area electric field.

[0010] The formula for calculating the distortion change rate in the micro-area electric field is as follows: ; In the above formula is the total electric field distortion in the micro-area electric field at the i-th future time point.

[0011] Another aspect of the present invention provides a leakage monitoring and protection system for a high-voltage power supply of a mass spectrometer, comprising: an electric field detection module, a signal acquisition module and a leakage protection module, wherein the above modules are connected by wired and / or wireless connection to achieve data transmission between the modules; Electric field detection module: a layer of gold nanorod array film is embedded in the vacuum coating layer of the mass spectrometer high-voltage power supply electrode, and a group of gold nanorod arrays are arranged near the mass spectrometer high-voltage power supply output electrode. The plasma resonance effect of the local surface of the gold nanorod array is used to detect the micro-area electric field on the surface of the corresponding electrode of the mass spectrometer high-voltage power supply; Signal acquisition module: When a change in the electric field in a micro-area is detected, the light source is modulated to emit a laser of a specific wavelength to capture the real-time electric field distortion signal; a dual-frequency lock-in amplifier is used to extract the specific harmonic components of the real-time electric field distortion signal to obtain a real-time electric field distortion signal with a high signal-to-noise ratio; Leakage protection module: Based on the real-time electric field distortion signal with high signal-to-noise ratio, the leakage assessment coefficient at each future time point is predicted; when the leakage assessment coefficient at a future time point is about to reach the set threshold coefficient, the system triggers the protection mechanism in advance within milliseconds and cuts off the high-voltage power output.

[0012] As described above, the present invention provides a method and system for monitoring and protecting leakage of a high voltage power supply of a mass spectrometer, which has at least the following beneficial effects: The embodiment of the present invention uses the localized surface plasmon resonance (LSPR) effect of the gold nanorod array to detect the electric field in a micro area, which can achieve high-sensitivity monitoring of electric field changes. It is crucial to timely identify potential leakage risks, especially in precision equipment such as mass spectrometers, where any slight electric field change may lead to a significant decrease in equipment performance or safety hazards; By modulating the light source to emit lasers of a specific wavelength, the LSPR effect of the gold nanorod array can be accurately stimulated, thereby capturing the electric field distortion signal in real time. The working state of the high-voltage power supply of the mass spectrometer may change in an instant. Rapidly capturing the electric field change signal can provide an accurate data basis for subsequent leakage trend prediction; The prediction model for leakage assessment based on real-time electric field distortion signals with high signal-to-noise ratio can quantify the leakage risk at future time points by establishing a mathematical model, so that the system can take protective measures in advance before the leakage risk reaches the dangerous threshold, cut off the high-voltage power supply output, and realize comprehensive monitoring and intelligent management of the high-voltage power supply of the mass spectrometer. This integrated system not only improves the safety and stability of the equipment, but also reduces the need for manual intervention and reduces operational risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0014] Figure 1 It is a schematic diagram of the connection of each step of the method of the present invention.

[0015] Figure 2 It is a schematic diagram of the connection of various modules of the system of the present invention. DETAILED DESCRIPTION

[0016] The above contents in combination with the implementation of the present invention are merely examples and explanations of the concept of the present invention. The technical personnel in the relevant technical field may make various modifications or supplements to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the concept of the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

[0017] Example 1 See also Figure 1 As shown, a leakage monitoring and protection method for a high voltage power supply of a mass spectrometer comprises the following steps: A layer of gold nanorod array film is embedded in the vacuum coating layer of the high-voltage power supply electrode of the mass spectrometer, and a group of gold nanorod arrays are arranged near the output electrode of the high-voltage power supply of the mass spectrometer. The plasma resonance effect of the local surface of the gold nanorod array is used to detect the micro-area electric field on the surface of the corresponding electrode of the high-voltage power supply of the mass spectrometer; A periodic gold nanorod array is embedded in the vacuum coating layer on the surface of the high-voltage electrode. The gold nanorods have a length of 120±5nm, a diameter of 25±2nm, an array spacing of 300nm, and a coating thickness not exceeding 5μm. The array forms full-surface equipotential contact with the high-voltage electrode through a magnetron sputtering process, and utilizes the localized surface plasmon resonance (LSPR) effect of gold nanorods to sense in real time the electric field distortion caused by trace adsorbents or structural defects within 5μm of the electrode surface.

[0018] When a change in the electric field in a micro-area is detected, the light source is modulated to emit a laser of a specific wavelength, thereby capturing the real-time electric field distortion signal; a dual-frequency lock-in amplifier is used to extract the specific harmonic components of the real-time electric field distortion signal, thereby obtaining a real-time electric field distortion signal with a high signal-to-noise ratio; When a change in the electric field in the micro area is detected, the implementation logic is: Collect the LSPR resonance wavelength of the gold nanorod array, record the initial wavelength λ0 and the wavelength λ at the current time point, calculate the difference between the wavelength λ at the current time point and the initial wavelength λ0, and obtain the wavelength offset △λ at the current time point; The wavelength shift △λ at the current time point is integrated with the wavelength shifts at previous time points, and the time derivatives of all time points are calculated to obtain the wavelength shift rate λ' at all time points; Obtaining experimentally calibrated sensitivity of gold nanorod arrays to changes in local electric fields , the dielectric constant of the coating layer ε and the dielectric constant of the vacuum ε0, and the static electric field distortion in the micro-area electric field is calculated respectively and dynamic electric field distortion ; The calculation formula of α1 reflects the intensity of static electric field distortion. The LSPR effect of gold nanorods responds directly to changes in the local electric field. The resonant wavelength shift Δλ is linearly related to the electric field change, and the proportionality coefficient is Therefore, through experimental calibration △λ can be directly converted into electric field distortion intensity; The calculation formula of α2 introduces the influence of dynamic electric field changes. Electric field distortion is usually accompanied by dynamic changes in time, and the rate of change of LSPR resonance wavelength offset λ' can describe this dynamic trend. In order to consider the amplification effect of the dielectric properties of the coating layer on the electric field change, a correction factor of the ratio of the dielectric constant of the coating layer to the dielectric constant of the vacuum is introduced.

[0019] The static electric field distortion α1 and the dynamic electric field distortion α2 in the micro-area electric field are summed to obtain the total electric field distortion in the micro-area electric field. Compare the total electric field distortion in the micro-area electric field with the set distortion threshold: If the former is greater than the latter, it is determined that the electric field in the micro-region has changed; Otherwise, it is determined that the electric field in the micro-region has not changed.

[0020] The calculation process of the total electric field distortion in the micro-area electric field combines static electric field distortion and dynamic electric field distortion. By linking the LSPR resonance wavelength shift of the gold nanorod array with the electric field change, the formula can sensitively detect the static change of the electric field. This sensitivity comes from the high sensitivity of gold nanorods to electric field changes, which can produce measurable resonance wavelength shifts under small electric field disturbances. Experiments have shown that the LSPR effect of gold nanorods responds linearly to electric field changes, which makes △λ a reliable indicator of electric field changes; Secondly, the dynamic electric field changes are reflected by the wavelength shift rate λ', which captures the temporal dynamics of the electric field changes and provides real-time monitoring capabilities for the electric field distortion trend. By introducing the dielectric constant ε of the coating layer, the formula takes into account the amplification effect of the medium on the electric field changes, making the calculation more in line with the actual situation. In reality, rapid changes in the electric field may indicate potential leakage risks, so dynamic monitoring is the key to achieving prediction and protection; In practical applications, the sensitivity coefficient and dielectric constant of gold nanorods can be calibrated experimentally; in summary, by integrating static and dynamic electric field changes and considering dielectric properties, an efficient and accurate electric field distortion detection method is provided. This is particularly important in precision equipment such as mass spectrometers, because timely and accurate detection of electric field distortion can effectively prevent leakage risks and ensure the safe operation and long-term stability of the equipment.

[0021] By modulating the light source to emit laser of a specific wavelength, the logic is as follows: Extracting Plasmon Frequencies of Gold Nanorod Materials from the Gold Nanorod Database , and then calculate the intrinsic plasma wavelength of the gold nanorod material , where c is the speed of light; Simultaneous calculation of the equivalent dielectric constant of the dielectric layer surrounding the gold nanorods ,in represent the refractive index and thickness of the silicon dioxide layer in the dielectric layer surrounding the gold nanorods, respectively; represent the refractive index and thickness of the tantalum pentoxide layer in the dielectric layer around the gold nanorods, is the total thickness of the dielectric layer; The refractive index of the silicon dioxide layer and the refractive index of the tantalum pentoxide layer are both dimensionless values ​​used to describe the change in the speed of light when it propagates in the material. It is defined as the ratio of the speed of light in vertical space to the speed of light in the material; ≈1.46, which means that within the wavelength range of light, the speed of light propagating in the silicon dioxide layer is about 68.5% of the speed of light in a vacuum; ≈2.18, indicating that the speed of light propagating in the tantalum pentoxide layer is slower, and the speed of light is about 45.9% of its speed in a vacuum.

[0022] The real part of the dielectric parameter ε1 of the gold nanorod material in the optical frequency band is calculated based on the Drude model, so as to calculate the optimal incident laser wavelength for exciting the LSPR effect of the gold nanorod array. , where Γ is the plasma frequency correction value caused by the finite size of the gold nanorods, , R is the aspect ratio of the gold nanorod, R=L / D, L and D represent the length and diameter of the gold nanorod, respectively; P is the depolarization factor, which represents the correction value of the gold nanorod geometry to the electric field distribution, .

[0023] The aspect ratio R plays an important role in the optical properties of nanomaterials, especially in the localized surface plasmon resonance (LSPR) phenomenon. The change of aspect ratio affects the resonance wavelength and electric field enhancement characteristics, so the aspect ratio is a key parameter in the design and optimization of sensors and optical devices based on gold nanorods; The aspect ratio R is calculated as R=L / D, which is used to describe the geometry of the nanorods, indicating the relationship between their extension in the length direction and their diameter. The larger the aspect ratio, the thinner the nanorods are, which has a significant impact on their optical properties, especially the localized surface plasmon resonance (LSPR); In the formula for calculating the depolarization factor P, the form (D / L)^1.7 is used. Here P represents the depolarization factor, which is a correction factor used to describe the effect of the nanorod geometry on the electric field distribution and resonance characteristics. The depolarization factor reflects the effect of the nanorod's slenderness on its electric field intensity distribution. Since the nanorod's geometry affects the distribution of its local electric field, a smaller diameter (relative to the length) will lead to a stronger electric field concentration effect, so the ratio of diameter to length is introduced in the calculation; In this case, the form (D / L)^1.7 is derived based on experience and theoretical models, showing that the depolarization effect of the electric field increases significantly as the diameter increases relative to the length. This exponent (1.7) is derived from experimental data and theoretical analysis, reflecting the nonlinear effects of geometry on optical properties.

[0024] Obtain real-time electric field distortion signals with high signal-to-noise ratio, including: The real-time electric field distortion signal is assumed to consist of the distortion signal and the environmental noise: , is the amplitude of the distorted signal, is the frequency of the distorted signal, is the initial phase of the distorted signal, is the environmental noise signal; A sine wave with a base frequency of f1 = 1 kHz and a sub-frequency of f2 = 2.5 kHz is selected as the laser modulation signal. Two sinusoidal reference signals are generated by dual-frequency modulation of the laser of the modulated light source: ; The real-time electric field distortion signal Mixed with two sinusoidal reference signals respectively, two mixed signals are obtained: ; By expanding the two mixing signals through trigonometric functions, the two mixing signals are expressed as:

[0025] Perform low-pass filtering on the mixed signals V1 and V2 to remove the high-frequency components and retain only the frequency and The signal: ; The low-pass filtered signals V1' and V2' are phase-weighted and summed to obtain the final real-time electric field distortion signal with high signal-to-noise ratio. .

[0026] The detection of electric field distortion signals is usually interfered by complex environmental factors, such as electromagnetic noise in the environment, broadband interference signals, and noise generated by the high-voltage power supply itself. These interference signals often have strong randomness and broadband characteristics, which directly affect the accurate extraction of electric field distortion signals. The dual-frequency phase-locked amplification technology introduces two sinusoidal reference signals (base frequency and sub-frequency), mixes them with the input signal respectively, and combines them with a low-pass filter to effectively remove high-frequency noise and environmental interference, retaining only specific harmonic components related to the electric field distortion signal, thereby significantly improving the signal-to-noise ratio. The necessity of this method lies in that only under high signal-to-noise ratio conditions can weak electric field distortion signals be accurately captured to avoid false alarms or missed alarms in the leakage prediction system due to noise interference; The system obtains real-time electric field distortion signals with high signal-to-noise ratio through dual-frequency phase-locked amplification technology. Through real-time mixing and filtering, the system can extract the amplitude and phase information of the electric field distortion signal within milliseconds, ensuring the rapid response capability of leakage prediction. This real-time performance is particularly important in the high-voltage power supply of the mass spectrometer, because the leakage risk of the high-voltage power supply may develop rapidly in a very short time. Only by capturing the electric field distortion signal in real time can millisecond-level advance protection be achieved. In summary, the real-time electric field distortion signal with high signal-to-noise ratio obtained based on dual-frequency phase-locked amplification technology not only has significant anti-interference ability and real-time advantages in theory, but has also been fully verified in experimental data and practical applications. This method provides accurate and reliable electric field distortion signal input for the leakage prediction system, thereby significantly improving the sensitivity and safety of the system.

[0027] Based on the real-time electric field distortion signal with high signal-to-noise ratio, the leakage assessment coefficient at each future time point is predicted; when the leakage assessment coefficient at a certain future time point is about to reach the set threshold coefficient, the system triggers the protection mechanism in advance within milliseconds and cuts off the high-voltage power supply output.

[0028] Predict leakage assessment coefficients at various future time points, including: The total electric field distortion in the micro-area electric field at M consecutive historical time points is collected to form a total electric field distortion sequence: , △τ is the historical data sampling interval, M is the historical data window length, t is the current time point, and α is the total electric field distortion in the micro-area electric field; The time decay weight of each historical time point is calculated from this , e is a natural constant, ρ is a decay rate constant, which is determined by fitting the autocorrelation function of historical data, j is the reverse index of the historical time point, j=1 represents the most recent moment, and j=M represents the earliest moment; The current time point is recorded as t, and each future time point is defined as , where i is the number of each future time point, i=1,2,...N, N is the total number of future time points, is the time interval difference between each future time point and the current time point; The leakage assessment coefficient at each future time point is calculated from this Where η1 is the contribution weight of historical electric field distortion data, , They respectively represent the fluctuation degree of the electric field distortion signal and the fluctuation degree of the system noise within the length of the historical data window; The above calculation formula predicts the leakage risk assessment coefficient at a future time point by combining the historical electric field distortion trend and the current electric field change rate. The formula weightedly fuses the past electric field distortion signal (historical trend term) with the current dynamic change (dynamic response term), taking into account both the long-term trend and the impact of short-term changes on future risks, thereby achieving an accurate prediction of leakage risk; The historical trend of the electric field distortion signal often reflects the cumulative effect of leakage risk. If the electric field distortion continues to increase over a period of time, it indicates that the leakage risk may gradually increase. The introduction of time decay weights can reduce the interference of earlier data on current predictions and highlight the importance of recent data. The change in leakage risk is usually closely related to the rate of electric field distortion. If the current rate of change of the electric field is large, the leakage risk may increase sharply in the short term. The exponential decay factor ensures that the impact of the dynamic response term gradually weakens as the prediction time increases, which is in line with the laws of physics (i.e. the short-term nature of the dynamic impact); The dynamic response term can quickly capture the dramatic changes in electric field distortion in the short term, making up for the shortcomings of the historical trend term in responding insufficiently to sudden events. The exponential decay factor can prevent the dynamic response term from having too much impact on the results in long-term predictions, and maintain the stability of the prediction. The historical trend term captures the long-term accumulated electric field distortion trend and provides a stable baseline prediction. The dynamic response term captures the rapid changes in the current electric field distortion and improves the sensitivity to sudden risks.

[0029] The exponential decay factor in the dynamic response term in the above calculation formula is and forecast time span Related: Assume that the electric field distortion at the current moment is at a rate Continuous development, but due to the thermal inertia of dielectric materials, the growth rate of leakage risk will gradually slow down over time: when =1s, exp(-1 / 8.5)≈0.89; γ is characterized by 8.5s; when =5s, exp(-5 / 8.5)≈0.54; Import it into a dynamic response item In the case of the same electric field change rate, the dynamic response contribution is reduced by about 39% due to exponential decay; η2 is the sensitivity coefficient of the electric field change rate, γ is the time inertia of the leakage development process, exp(·) represents the exponential function with the natural number e as the base, is the total electric field distortion in the micro-area electric field at the jth historical time point, is the distortion change rate at each future time point in the micro-area electric field.

[0030] The formula for calculating the distortion change rate in the micro-area electric field is as follows: ; In the above formula is the total electric field distortion in the micro-area electric field at the i-th future time point.

[0031] It should be added that when the leakage assessment coefficient at a certain future time point is about to reach the set threshold coefficient, the meaning is: when the set threshold coefficient is subtracted from the leakage assessment coefficient at a certain future time point, the leakage assessment difference coefficient at a certain future time point is obtained. If the leakage assessment difference coefficient at a certain future time point is less than the maximum allowable threshold, it is determined that there is a leakage risk at that future time point, and the system triggers the protection mechanism in advance within milliseconds to cut off the high-voltage power supply output.

[0032] Example 2 See also Figure 2 As shown, a leakage monitoring and protection system for a high-voltage power supply of a mass spectrometer includes: an electric field detection module, a signal acquisition module and a leakage protection module, wherein the above modules are connected by wired and / or wireless connection to realize data transmission between the modules; Electric field detection module: a layer of gold nanorod array film is embedded in the vacuum coating layer of the mass spectrometer high-voltage power supply electrode, and a group of gold nanorod arrays are arranged near the mass spectrometer high-voltage power supply output electrode. The plasma resonance effect of the local surface of the gold nanorod array is used to detect the micro-area electric field on the surface of the corresponding electrode of the mass spectrometer high-voltage power supply; Signal acquisition module: When a change in the electric field in a micro-area is detected, the light source is modulated to emit a laser of a specific wavelength to capture the real-time electric field distortion signal; a dual-frequency lock-in amplifier is used to extract the specific harmonic components of the real-time electric field distortion signal to obtain a real-time electric field distortion signal with a high signal-to-noise ratio; Leakage protection module: Based on the real-time electric field distortion signal with high signal-to-noise ratio, the leakage assessment coefficient at each future time point is predicted; when the leakage assessment coefficient at a future time point is about to reach the set threshold coefficient, the system triggers the protection mechanism in advance within milliseconds and cuts off the high-voltage power output.

[0033] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean 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 the present application.

[0034] It should be understood that determining B based on A does not mean determining B only based on A. B can also be determined based on A and / or other information.

[0035] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0036] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A leakage monitoring and protection method for a high voltage power supply of a mass spectrometer, characterized in that: include: A layer of gold nanorod array film is embedded in the vacuum coating layer of the high-voltage power supply electrode of the mass spectrometer, and a group of gold nanorod arrays are arranged near the output electrode of the high-voltage power supply of the mass spectrometer. The plasma resonance effect of the local surface of the gold nanorod array is used to detect the micro-area electric field on the surface of the corresponding electrode of the high-voltage power supply of the mass spectrometer; When a change in the electric field in a micro-area is detected, the light source is modulated to emit a laser of a specific wavelength, thereby capturing the real-time electric field distortion signal; a dual-frequency lock-in amplifier is used to extract the specific harmonic components of the real-time electric field distortion signal, thereby obtaining a real-time electric field distortion signal with a high signal-to-noise ratio; Based on the real-time electric field distortion signal with high signal-to-noise ratio, the leakage assessment coefficient at each future time point is predicted; when the leakage assessment coefficient at a certain future time point is about to reach the set threshold coefficient, the system triggers the protection mechanism in advance within milliseconds and cuts off the high-voltage power supply output.

2. The method for monitoring and protecting leakage of a high voltage power supply for a mass spectrometer according to claim 1, characterized in that: When a change in the electric field in the micro area is detected, the implementation logic is: Collect the LSPR resonance wavelength of the gold nanorod array, record the initial wavelength λ0 and the wavelength λ at the current time point, calculate the difference between the wavelength λ at the current time point and the initial wavelength λ0, and obtain the wavelength offset △λ at the current time point; The wavelength shift △λ at the current time point is integrated with the wavelength shifts at previous time points, and the time derivatives of all time points are calculated to obtain the wavelength shift rate λ' at all time points; Obtaining experimentally calibrated sensitivity of gold nanorod arrays to changes in local electric fields , the dielectric constant of the coating layer ε and the dielectric constant of the vacuum ε0, and the static electric field distortion in the micro-area electric field is calculated respectively and dynamic electric field distortion ; The static electric field distortion α1 and the dynamic electric field distortion α2 in the micro-area electric field are summed to obtain the total electric field distortion in the micro-area electric field. Compare the total electric field distortion in the micro-area electric field with the set distortion threshold: If the former is greater than the latter, it is determined that the electric field in the micro-region has changed; Otherwise, it is determined that the electric field in the micro-region has not changed.

3. The method for monitoring and protecting leakage of a high voltage power supply for a mass spectrometer according to claim 1, characterized in that: By modulating the light source to emit laser of a specific wavelength, the logic is as follows: Extracting Plasmon Frequencies of Gold Nanorod Materials from the Gold Nanorod Database , and then calculate the intrinsic plasma wavelength of the gold nanorod material , where c is the speed of light; Simultaneous calculation of the equivalent dielectric constant of the dielectric layer surrounding the gold nanorods ,in represent the refractive index and thickness of the silicon dioxide layer in the dielectric layer surrounding the gold nanorods, respectively; represent the refractive index and thickness of the tantalum pentoxide layer in the dielectric layer around the gold nanorods, is the total thickness of the dielectric layer; The real part of the dielectric parameter ε1 of the gold nanorod material in the optical frequency band is calculated based on the Drude model, so as to calculate the optimal incident laser wavelength for exciting the LSPR effect of the gold nanorod array. , where Γ is the plasma frequency correction value caused by the finite size of the gold nanorods, , R is the aspect ratio of the gold nanorod, R=L / D, L and D represent the length and diameter of the gold nanorod, respectively; P is the depolarization factor, which represents the correction value of the gold nanorod geometry to the electric field distribution, .

4. The method for monitoring and protecting leakage of a high voltage power supply for a mass spectrometer according to claim 1, characterized in that: Obtain real-time electric field distortion signals with high signal-to-noise ratio, including: The real-time electric field distortion signal is assumed to consist of the distortion signal and the environmental noise: , is the amplitude of the distorted signal, is the frequency of the distorted signal, is the initial phase of the distorted signal, is the environmental noise signal; A sine wave with a base frequency of f1 = 1 kHz and a sub-frequency of f2 = 2.5 kHz is selected as the laser modulation signal. Two sinusoidal reference signals are generated by dual-frequency modulation of the laser of the modulated light source: ； The real-time electric field distortion signal Mixed with two sinusoidal reference signals respectively, two mixed signals are obtained: ； Perform low-pass filtering on the mixed signals V1 and V2 to remove the high-frequency components and retain only the frequency and The signal: ； The low-pass filtered signals V1' and V2' are phase-weighted and summed to obtain the final real-time electric field distortion signal with high signal-to-noise ratio. .

5. The method for monitoring and protecting leakage of a high voltage power supply for a mass spectrometer according to claim 1, characterized in that: Predict leakage assessment coefficients at various future time points, including: The total electric field distortion in the micro-area electric field at M consecutive historical time points is collected to form a total electric field distortion sequence: , △τ is the historical data sampling interval, M is the historical data window length, t is the current time point, and α is the total electric field distortion in the micro-area electric field; The time decay weight of each historical time point is calculated from this , e is a natural constant, ρ is a decay rate constant, which is determined by fitting the autocorrelation function of historical data, j is the reverse index of the historical time point, j=1 represents the most recent moment, and j=M represents the earliest moment; The current time point is recorded as t, and each future time point is defined as , where i is the number of each future time point, i=1,2,...N, N is the total number of future time points, is the time interval difference between each future time point and the current time point; The leakage assessment coefficient at each future time point is calculated from this Where η1 is the contribution weight of historical electric field distortion data, , They respectively represent the fluctuation degree of the electric field distortion signal and the fluctuation degree of the system noise within the length of the historical data window; η2 is the sensitivity coefficient of the electric field change rate, γ is the time inertia of the leakage development process, exp(·) represents the exponential function with the natural number e as the base, is the total electric field distortion in the micro-area electric field at the jth historical time point, is the distortion change rate at each future time point in the micro-area electric field.

6. A leakage monitoring and protection method for a high voltage power supply of a mass spectrometer according to claim 5, characterized in that: The formula for calculating the distortion change rate in the micro-area electric field is as follows: ； In the above formula is the total electric field distortion in the micro-area electric field at the i-th future time point.

7. A leakage monitoring and protection system for a high voltage power supply of a mass spectrometer, characterized in that: A leakage monitoring and protection method for a high-voltage power supply of a mass spectrometer as described in any one of claims 1 to 6 is implemented, comprising: an electric field detection module, a signal acquisition module and a leakage protection module, wherein the above modules are connected by wired and / or wireless connection to realize data transmission between the modules; Electric field detection module: a layer of gold nanorod array film is embedded in the vacuum coating layer of the mass spectrometer high-voltage power supply electrode, and a group of gold nanorod arrays are arranged near the mass spectrometer high-voltage power supply output electrode. The plasma resonance effect of the local surface of the gold nanorod array is used to detect the micro-area electric field on the surface of the corresponding electrode of the mass spectrometer high-voltage power supply; Signal acquisition module: When a change in the electric field in a micro-area is detected, the light source is modulated to emit a laser of a specific wavelength to capture the real-time electric field distortion signal; a dual-frequency lock-in amplifier is used to extract the specific harmonic components of the real-time electric field distortion signal to obtain a real-time electric field distortion signal with a high signal-to-noise ratio; Leakage protection module: Based on the real-time electric field distortion signal with high signal-to-noise ratio, the leakage assessment coefficient at each future time point is predicted; when the leakage assessment coefficient at a future time point is about to reach the set threshold coefficient, the system triggers the protection mechanism in advance within milliseconds and cuts off the high-voltage power output.

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