A method and system for real-time monitoring of neutron tube gas pressure

Abstract

This invention belongs to the field of nuclear reactor monitoring technology, specifically relating to a method and system for real-time monitoring of neutron tube pressure. The method includes: acquiring basic electrical parameters and environmental data from the neutron tube's operating cycle, performing statistical calculations to obtain the average voltage of the hydrogen storage tank, the average current of the hydrogen storage tank, the average output current of the ion source, and the standard deviation of the ion source output current; calculating the effective thermal thrust index, beam fluctuation index, and thermoelectric conversion quality score; obtaining a corrected pressure value; converting the corrected pressure value into a real-time physical pressure value; generating adjustment commands for increasing, decreasing, or maintaining pressure based on the real-time physical pressure value; and adjusting the hydrogen storage tank current according to the adjustment commands. This invention effectively solves the problem that traditional methods struggle to accurately invert the true pressure inside the tube from a single dimension, leading to lag or inaccuracy in pressure regulation.

Description

Technical Field

[0001] This invention relates to the field of nuclear reactor monitoring technology. More specifically, this invention relates to a method and system for real-time monitoring of neutron tube gas pressure. Background Technology

[0002] In the field of oil exploration and development, pulsed neutron logging technology is often used for reservoir evaluation. As the core component of this type of instrument, the stability of the internal gas pressure, i.e. the density of deuterium and tritium gas, directly determines the neutron yield and the service life of the instrument.

[0003] Existing neutron tube gas pressure control typically employs a constant current method or a simple target current feedback method, adjusting the heating current of the hydrogen storage device to control the gas release rate. However, in deep well operations, the ambient temperature often reaches as high as 175°C, as seen in the operating conditions of Xi'an Aohua Electronics' NGT series neutron generator. High temperatures can cause nonlinear drift in the gas absorption and release characteristics of the hydrogen storage device, while the discharge efficiency of the ion source will also fluctuate under different gas pressures.

[0004] The main drawback of existing technologies is that they focus only on single-current feedback, neglecting the energy input—the energy conversion relationship between hydrogen storage heating and physical output—the efficiency conversion relationship between the ion source and the target. When the gas pressure is abnormal, phenomena often occur where the heating power is high but the effective discharge is insufficient, or the discharge is violent but uncontrollable. Traditional methods cannot accurately invert the true gas pressure inside the tube from a single dimension, leading to lag or inaccuracy in gas pressure regulation. This lag and inaccuracy not only cause significant fluctuations in neutron production, reducing the accuracy and reliability of logging data, but may also accelerate the aging and wear of the electrodes inside the neutron tube due to gas pressure imbalance, severely shortening the instrument's continuous downhole operating time. Summary of the Invention

[0005] To address the technical problem that traditional methods are unable to accurately invert the actual air pressure inside the pipe using a single dimension, leading to lag or inaccuracy in air pressure regulation, this invention provides solutions in the following aspects.

[0006] In a first aspect, the present invention provides a method for real-time monitoring of neutron tube gas pressure, comprising:

[0007] The system acquires basic electrical parameters and environmental data for the neutron tube's operating cycle and performs statistical calculations to obtain the average voltage, average current, mean ion source output current, and standard deviation of the ion source output current. Combining the average voltage and average current of the hydrogen storage unit, it analyzes the amplification of the basic electrothermal power by the storage unit's current state and calculates the effective thermal thrust index. Based on the fluctuation of the ion source output current, it calculates the beam fluctuation index. Combining the effective thermal thrust index, beam fluctuation index, and the matching degree between the ion source output current and the target output current set under the current operating conditions, it calculates the thermoelectric conversion quality score. Based on the difference between the external ambient temperature and the pre-acquired standard room temperature, it corrects the thermoelectric conversion quality score to obtain a corrected pressure value. According to the characteristic pressure mapping relationship, it converts the corrected pressure value into a real-time physical pressure value. Based on the real-time physical pressure value, it generates adjustment commands for increasing, decreasing, or maintaining pressure. The hydrogen storage unit current is adjusted according to the adjustment commands.

[0008] This invention effectively solves the problem of untimely or inaccurate adjustments caused by relying solely on single-dimensional data to determine the internal air pressure of equipment in traditional methods. This invention employs multi-step data acquisition, statistics, and calculation, comprehensively considering factors such as energy input, output stability, target achievement, and ambient temperature. First, reliable basic data is obtained through statistical calculations. Then, the equipment's operating status is comprehensively evaluated through the calculation of various indices and scores. Finally, combined with ambient temperature correction and data mapping transformation, the real-time physical air pressure is accurately obtained, and adjustments are made accordingly. This progressive process avoids the limitations of single-data assessments and the interference of environmental factors, resulting in more accurate air pressure judgments and more timely and appropriate adjustments. It reduces equipment output fluctuations and losses caused by air pressure imbalances, improving the overall reliability of monitoring and adjustment.

[0009] Preferably, the basic electrical parameters and environmental data of the neutron tube's operating cycle are obtained and statistically calculated to obtain the average voltage of the hydrogen storage device, the average current of the hydrogen storage device, the mean value of the ion source output current, and the standard deviation of the ion source output current, including:

[0010] The system collects in real time the instantaneous values ​​of the voltage across the hydrogen storage device, the instantaneous values ​​of the hydrogen storage device circuit current, the instantaneous values ​​of the ion source output current, and the ambient temperature outside the tube during a single firing cycle; it then performs statistical calculations on the collected data to obtain the average voltage of the hydrogen storage device, the average current of the hydrogen storage device, the mean of the ion source output current, and the standard deviation of the ion source output current.

[0011] Preferably, the effective thermal thrust index satisfies the following expression:

[0012] ;

[0013] In the formula, Indicates the effective thermal thrust index; and These are the average voltage and average current of the hydrogen storage device, respectively. The nominal resistance of the hydrogen storage device in the cold state; It is the natural logarithm function; This represents the first smallest positive number, and the denominator is guaranteed to be non-zero.

[0014] This invention, by combining relevant parameters and specific functions for calculation, more accurately reflects the conversion of equipment energy input into actual driving capability. It takes into account the impact of equipment state changes on energy performance, avoids the bias of judging driving capability solely based on surface power data, and makes energy-driven assessments more in line with actual working scenarios, helping to more accurately grasp the potential capability of air pressure regulation in the future.

[0015] Preferably, the beam fluctuation index satisfies the following expression:

[0016] ;

[0017] In the formula, Indicates the beam fluctuation index; The standard deviation of the ion source output flow; This represents the average output current of the ion source. This is the maximum designed output flow of the ion source; , The numbers are the second and third smallest positive numbers, ensuring that the denominator is not zero; This represents an exponential function with the natural constant as its base.

[0018] This invention calculates by integrating data fluctuations and relevant limiting parameters, which can more sensitively capture unstable characteristics of equipment output. This calculation method amplifies minute abnormal signals, making early signs of instability easier to detect, avoiding judgment delays caused by ignoring subtle fluctuations, helping to detect pressure-related anomalies in a timely manner, and providing timely support for equipment protection.

[0019] Preferably, the thermoelectric conversion quality score satisfies the following expression:

[0020] ;

[0021] In the formula, Indicates the quality score of thermoelectric conversion; The effective thermal thrust index; Beam fluctuation index ; represents the average output current of the ion source; Set the target output stream for the current operating condition; It is the equilibrium constant; It is the fourth smallest positive number, ensuring that the denominator is not zero; This represents the maximum value function.

[0022] This invention provides a comprehensive evaluation by integrating energy drive, output stability, and target achievement, which fully reflects the matching degree between the energy input and output effect of the equipment. It avoids the one-sidedness of single-dimensional evaluation, taking into account both energy utilization efficiency and output stability and accuracy, making the evaluation of the equipment's working status more comprehensive and objective, and providing a reasonable basis for subsequent pressure correction.

[0023] Preferably, obtaining the corrected air pressure value includes:

[0024] Obtain the standard room temperature constant and calculate the difference between the external ambient temperature and the standard room temperature constant. Multiply this difference by the thermistor compensation coefficient and add the product to 1, which is recorded as the thermal drift compensation correction term. Multiply the thermoelectric conversion quality score by the thermal drift compensation correction term to obtain the corrected pressure value.

[0025] This invention, by incorporating adjustments based on ambient temperature differences, eliminates the impact of ambient temperature variations on the evaluation results. This correction method restores the true state of the equipment under standard conditions, avoids judgment biases caused by ambient temperature fluctuations, and makes the obtained air pressure-related data closer to the actual situation, improving the accuracy of air pressure evaluation and providing a reliable reference for subsequent air pressure conversion and adjustment.

[0026] Preferably, converting the corrected pressure value into a real-time physical pressure value includes:

[0027] The system retrieves pre-acquired characteristic pressure mapping data, uses the corrected pressure value as the index key input, and outputs the real-time physical pressure value inside the neutron tube through an interpolation matching algorithm.

[0028] This invention transforms abstract feature data into intuitive and easily understood physical values ​​by matching preset mapping data with a specific algorithm. This transformation establishes a connection between the data and the actual physical state, allowing staff to more directly grasp the internal air pressure of the equipment, facilitating subsequent threshold setting and troubleshooting, and improving the practicality of the monitoring results.

[0029] Preferably, based on the real-time physical pressure value, a control command is generated to increase, decrease, or maintain the pressure, including:

[0030] The system retrieves the optimal operating pressure range from the database and compares the real-time physical pressure value with the optimal operating pressure range. If the real-time physical pressure value is to the left of the optimal operating pressure range, the system generates a pressure increase regulation command. If the real-time physical pressure value is to the right of the optimal operating pressure range, the system generates a pressure decrease regulation command. If the real-time physical pressure value is within the optimal operating pressure range, including the range boundary, the system maintains the current hydrogen storage tank current.

[0031] Preferably, adjusting the hydrogen storage tank current according to the adjustment command includes:

[0032] The system adjusts the heating current of the hydrogen storage tank according to the generated adjustment instructions, and at the same time packages and uploads the real-time physical gas pressure value, the external ambient temperature and the thermoelectric conversion quality score to the host computer display interface to complete this monitoring cycle.

[0033] Secondly, the present invention provides a real-time neutron tube pressure monitoring system, including a processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, the above-mentioned real-time neutron tube pressure monitoring method is implemented.

[0034] By adopting the above technical solution, a computer program for real-time monitoring of neutron tube pressure is generated and stored in a memory for loading and execution by a processor. A terminal device is then created based on the memory and processor for convenient use.

[0035] The beneficial effects of this invention are as follows: Through scientific data analysis and calculation processes, this invention continuously and accurately monitors the internal air pressure status of the equipment and makes timely adjustments to maintain stable operation. This not only helps improve the reliability of relevant operational data and ensure operational effectiveness, but also reduces equipment failures and losses caused by air pressure issues, extends equipment lifespan, and lowers maintenance costs and risks during operation. Furthermore, the solution has a clear operational logic, timely data upload and status feedback, facilitating comprehensive equipment management by staff and providing strong support for the smooth execution of related operations, thus possessing broad application prospects. Attached Figure Description

[0036] Figure 1 This is a flowchart illustrating a real-time neutron tube pressure monitoring method according to the present invention;

[0037] Figure 2 This is a schematic diagram illustrating the real-time acquisition of basic electrical parameters of the hydrogen storage device and ambient temperature in this invention;

[0038] Figure 3 This is a schematic diagram illustrating the trend of the beam fluctuation index changing with the monitoring period in this invention. Detailed Implementation

[0039] This invention discloses a method for real-time monitoring of neutron tube gas pressure, referring to... Figure 1 This includes steps S1-S4:

[0040] S1: Obtain the basic electrical parameters and environmental data of the neutron tube's working cycle, and perform statistical calculations to obtain the average voltage of the hydrogen storage device, the average current of the hydrogen storage device, the mean value of the ion source output current, and the standard deviation of the ion source output current.

[0041] It should be noted that in actual logging operations using neutron tubes, especially in the high-temperature and high-pressure environment thousands of meters underground, the neutron generator, as a black box system enclosed in a pressure-resistant shell, presents extremely difficult challenges in sensing its internal state. Traditional monitoring methods often rely on single-point sampling, such as reading the current value at a single instant. This approach is highly susceptible to interference from downhole power fluctuations, signal transmission noise, and circuit thermal noise, resulting in data that fails to accurately reflect the steady-state characteristics of the hydrogen storage tank and ion source. To construct a reliable analytical benchmark, statistical processing methods must be introduced to transform discrete, noisy instantaneous signals into statistically significant state characteristics. This invention, through high-frequency continuous sampling within a single firing cycle and the calculation of the mean and standard deviation, effectively performs time-domain filtering and feature reconstruction of the signal. The average voltage and current of the hydrogen storage tank reflect the steady-state level of the energy input, eliminating the influence of power supply ripple. The mean of the ion source output stream represents the macroscopic expectation of the neutron yield, while the standard deviation keenly captures the microscopic fluctuations during the discharge process. This data acquisition method based on full-cycle statistics provides a pure data foundation for subsequent analysis of the complex nonlinear relationship between thermo-electricity.

[0042] Specifically, the basic electrical parameters and environmental data of the neutron tube's operating cycle are obtained, and statistical calculations are performed to obtain the average voltage of the hydrogen storage device, the average current of the hydrogen storage device, the mean of the ion source output current, and the standard deviation of the ion source output current, including:

[0043] Upon initiating the neutron tube monitoring program, the system first reads a preset set of equipment calibration parameters from the memory. These parameters include: the nominal cold resistance of the hydrogen storage tank, the maximum design output current of the ion source, the target output current under current operating conditions, the balance constant, and the thermal compensation coefficient. The system then collects in real-time the instantaneous values ​​of the voltage across the hydrogen storage tank, the instantaneous current in the hydrogen storage tank circuit, the instantaneous output current of the ion source, and the ambient temperature outside the tube within a single firing cycle. Statistical calculations are performed on the collected data to obtain the average voltage of the hydrogen storage tank, the average current of the hydrogen storage tank, the mean of the ion source output current, and the standard deviation of the ion source output current.

[0044] Thus, the average voltage of the hydrogen storage device, the average current of the hydrogen storage device, the mean value of the ion source output current, and the standard deviation of the ion source output current were obtained.

[0045] It should be noted that, Figure 2 This image shows real-time data acquisition of the basic electrical parameters of the hydrogen storage tank and the ambient temperature, displaying the average voltage sequence, average current sequence of the hydrogen storage tank, and ambient temperature sequence, along with the plotted voltage curve, current curve, and ambient temperature curve. During monitoring period 11... Within the 25°C air pressure anomaly acquisition range, the voltage curve continuously deviates from the cold-state nominal voltage reference, while the current curve shows a slight adjustment. Meanwhile, the ambient temperature curve outside the pipe exhibits a slow rise and irregular fluctuation pattern consistent with deep well conditions. In the non-abnormal range, the voltage and current curves fluctuate slightly around the nominal reference, realistically reflecting the characteristics of stable parameters when the air pressure is stable and unstable parameters when the air pressure is abnormal in industrial scenarios.

[0046] S2: Combining the average voltage and average current of the hydrogen storage device, analyze the amplification of the basic electrothermal power due to the state of the hydrogen storage device, and calculate the effective thermal thrust index; calculate the beam fluctuation index based on the fluctuation of the ion source output flow.

[0047] It's important to note that the hydrogen storage unit, also known as a gas reservoir, acts as a fuel pump within the neutron tube. Its core material is typically a titanium or zirconium hydride. The gas absorption and release characteristics of these materials are not linear, exhibiting significant thermal hysteresis and impedance temperature drift. In practical control, simply focusing on the input electrical power is insufficient, because the same power output will elicit drastically different amounts of deuterium and tritium gas release depending on whether the storage unit is cold or hot. As the storage unit's temperature rises, its internal crystal structure undergoes subtle changes, macroscopically manifested as a non-linear increase in resistivity. If this impedance change and the resulting heat accumulation indication are ignored, the control system will misjudge the current driving capability. The effective thermal thrust index proposed in this invention cleverly utilizes the ratio of hot resistance to cold nominal resistance. This ratio is essentially a thermal state probe, revealing the current heat storage level of the hydrogen storage device. That is, through the smooth mapping of the logarithmic function, the system can identify those efficient driving states with low power but long heat storage, or those inefficient states with high power but not yet fully heated. This allows the system to see through the appearance of electrical parameters and directly reach the physical essence of thermal drive, thereby more accurately assessing the actual work potential of the gas pressure regulation end.

[0048] Specifically, by combining the average voltage and average current of the hydrogen storage tank, the amplification of the basic electrothermal power by the state of the hydrogen storage tank is analyzed, and the effective thermal thrust index is calculated, including:

[0049] The effective thermal thrust index satisfies the following expression:

[0050] ;

[0051] In the formula, Indicates the effective thermal thrust index; and These are the average voltage and average current of the hydrogen storage device, respectively. The nominal resistance of the hydrogen storage device in the cold state; It is the natural logarithm function; This represents the first smallest positive number, and the denominator is guaranteed to be non-zero.

[0052] In the formula, the first half of the formula Represents basic electric heating power; the second half It is the impedance change correction factor, where The formula uses the smoothing properties of the logarithmic function to convert the ratio of hot resistance to cold resistance into a gain coefficient for the thermal accumulation state. When the hot resistance is much greater than the cold resistance, it indicates that the hydrogen storage device is in a high thermal accumulation state, and the potential energy of the actual driving gas release is effectively amplified.

[0053] For example, , Read ,but 10W , , This result indicates that, considering the thermal accumulation effect, the actual potential energy used to drive the gas is higher than the basic electrothermal power, which is consistent with physical laws. The result is obtained by retaining two decimal places.

[0054] Thus, the effective thermal thrust index was obtained.

[0055] It is important to note that the discharge process of the ion source is the most direct barometer of the neutron tube's gas pressure state. Under ideal gas pressure, the Penning ion source should produce a stable and continuous ion beam. However, when the gas pressure inside the tube is too high, the mean free path of the gas molecules shortens, easily triggering microscopic arcing or even macroscopic sparking between the high-voltage electrodes. Conversely, if the gas pressure is too low, ignition becomes difficult, and the beam exhibits discontinuous characteristics. Traditional detection methods often only consider the beam current magnitude, neglecting its quality, i.e., stability. A seemingly acceptable average current may mask severe discharge fluctuations, indicating not only a failure in gas pressure control but also irreversible damage to the high-voltage insulation performance of the neutron tube. The beam fluctuation index introduced in this invention is not merely a calculation of the standard deviation but incorporates a nonlinear penalty mechanism based on design limits. Through the amplification effect of the exponential function, once the beam fluctuation approaches the system's safety boundary, this index will increase explosively. This method makes the algorithm highly sensitive to minute signs of pressure instability, enabling it to keenly identify discharge deterioration caused by abnormal pressure before catastrophic failures occur, providing a key early warning indicator for protecting expensive neutron tubes.

[0056] Preferably, the beam fluctuation index is calculated based on the fluctuation degree of the ion source output current, including:

[0057] The beam ripple index satisfies the following expression:

[0058] ;

[0059] In the formula, Indicates the beam fluctuation index; The standard deviation of the ion source output flow; This represents the average output current of the ion source. This is the maximum designed output flow of the ion source; , The numbers are the second and third smallest positive numbers, ensuring that the denominator is not zero; This represents an exponential function with the natural constant as its base.

[0060] In the formula, This is the coefficient of variation term, used to characterize the relative volatility of the data; As a non-linear penalty factor, when the standard deviation Approaching the system limit In cases such as severe sparking or arcing, the nonlinear penalty factor increases exponentially, thereby greatly amplifying the fluctuation index and enabling the algorithm to keenly capture microscopic pressure instability characteristics.

[0061] For example, during normal operation, , , ,but , , , A lower value indicates a stable condition within the pipe; if sparking occurs, If it surges to 40, then It will increase significantly and accurately reflect the characteristics of the fault. Retain to three decimal places.

[0062] Thus, the beam fluctuation index was obtained.

[0063] It should be noted that, Figure 3 This is a graph showing the trend of the beam fluctuation index over the monitoring period. The graph includes a real-time fluctuation curve characterizing the beam fluctuation index of this invention, a reference curve for the fluctuation coefficient using conventional methods, and a physical curve showing the actual gas pressure in the neutron tube. During monitoring period 11... Within the 25°C anomaly range, the actual pressure curve shows a significant decrease, while the beam fluctuation index curve of this invention rises sharply, reaching a peak value close to 0.18; whereas the fluctuation coefficient curve of the background technology only shows a slight change. This difference clearly demonstrates the technical advantage of this invention in amplifying the microscopic pressure instability characteristics through an exponential penalty factor; in the non-anomaly range, the fluctuation index curve of this invention falls back to... The nearby stable range matches the actual air pressure level.

[0064] S3: Calculate the thermoelectric conversion quality score by combining the effective thermal thrust index, beam fluctuation index, and the matching degree between the ion source output flow and the target output flow set under the current operating conditions; correct the thermoelectric conversion quality score based on the difference between the external ambient temperature and the pre-obtained standard room temperature to obtain the corrected gas pressure value.

[0065] It should be noted that the core contradiction in neutron tube pressure control lies in the imbalance between energy input and physical output. In actual operation, two extreme anomalies often occur: one is high consumption and low efficiency, where the heating current of the hydrogen storage unit is very large, but the ion source beam current remains weak. This usually indicates that the hydrogen storage unit material is aging or the getter has failed, resulting in the inability to establish pressure. The other is uncontrolled runaway, where the heating current is very small, but the beam current is abnormally large and fluctuates violently. This is often a precursor to gas breakdown caused by excessively high pressure. A single-dimensional parameter cannot simultaneously cover both situations. The thermoelectric conversion quality score constructed in this invention is essentially a multi-dimensional performance evaluation system. It organically integrates the thermal thrust at the front end with the beam stability and target achievement rate at the back end. The thermoelectric conversion quality score is not just a numerical value; it represents the current health of the neutron tube. A high score means that the system has obtained the most stable target beam at the lowest energy cost and is at the optimal pressure point, while a low score accurately points to the collapse of the energy efficiency ratio. This comprehensive evaluation mechanism solves the problem that traditional methods cannot distinguish between equipment aging and abnormal pressure, and realizes in-depth attribution diagnosis of pressure status.

[0066] Preferably, the thermoelectric conversion quality score is calculated by combining the effective thermal thrust index, beam fluctuation index, and the matching degree between the ion source output flow and the target output flow set under the current operating conditions, including:

[0067] Thermoelectric conversion quality score satisfies the following expression:

[0068] ;

[0069] In the formula, Indicates the quality score of thermoelectric conversion; The effective thermal thrust index; The beam fluctuation index; This represents the average output current of the ion source. Set the target output stream for the current operating condition; It is the equilibrium constant; It is the fourth smallest positive number, ensuring that the denominator is not zero; This represents the maximum value function.

[0070] In the formula, the first part Characterizing the driving energy consumption per unit stability cost, if the beam is extremely unstable, If the value is large, the thermoelectric conversion quality score drops sharply; Part Two To adjust the target achievement rate weights, a maximum value function is introduced here. Take the larger of the two values ​​within the parentheses. and When the deviation exceeds 100%, the calculated value of the latter term is negative. At this time, it is forced to be 0, which means that the target achievement rate is zero under this state and the system efficiency score is zero, so as to avoid negative scores. The thermoelectric conversion quality score expression comprehensively evaluates the high energy consumption or low quality state caused by unsuitable air pressure.

[0071] For example, , , , , Then the correction term is 1. This high score indicates moderate air pressure and perfect energy conversion. If abnormal air pressure causes fluctuations in the output flow, If it becomes 1.0, then A sharp drop to approximately 11.3 is a sensitive indicator of deteriorating barometric conditions.

[0072] It should be noted that one of the biggest challenges faced by oil well logging instruments is the high temperature in deep wells. For neutron tubes, an ambient temperature of 175°C is not only a test of physical tolerance but also a source of disturbance to physical laws. According to the ideal gas law, with constant volume, an increase in temperature will directly lead to an increase in the background gas pressure inside the tube, generating a false high-pressure phenomenon. At the same time, high temperature will change the lattice gaps of the hydrogen storage material, causing its gas absorption and desorption platforms to drift, and will also affect the permeability of the ion source magnet material, changing the discharge efficiency. If the algorithm calibrated on the surface is directly applied downhole, it will inevitably lead to serious misjudgments due to these thermal effects. For example, it may mistakenly identify the natural increase in gas pressure caused by high temperature as excessive heating current, thus incorrectly reducing the heating current and causing the neutron tube to shut down. Therefore, ambient temperature must be introduced as a key correction variable. The linear thermal compensation model used in this invention does not simply add or subtract values, but rather performs gain correction on the aforementioned calculated thermoelectric conversion quality score. Its physical significance lies in restoring the performance that the thermoelectric conversion quality score should have under standard room temperature, eliminating the interference of environmental thermal noise on the system performance evaluation, and ensuring that the thermoelectric conversion quality score can truly reflect the essential performance of the gas pressure control system at any well temperature and depth.

[0073] Specifically, the thermoelectric conversion quality score is corrected based on the difference between the external ambient temperature and the pre-obtained standard room temperature to obtain a corrected pressure value, including:

[0074] Obtain the standard room temperature constant and calculate the difference between the external ambient temperature and the standard room temperature constant. Multiply this difference by the thermistor compensation coefficient and add the product to 1, which is recorded as the thermal drift compensation correction term. Multiply the thermoelectric conversion quality score by the thermal drift compensation correction term to obtain the corrected pressure value.

[0075] S4: Based on the characteristic pressure mapping relationship, convert the corrected pressure value into a real-time physical pressure value; based on the real-time physical pressure value, generate a pressure increase, pressure decrease, or pressure maintenance adjustment command; adjust the hydrogen storage tank current according to the adjustment command.

[0076] It should be noted that for on-site operators or the host computer control system, correcting the air pressure value lacks intuitive physical meaning and is difficult to use directly for setting thresholds or troubleshooting. Therefore, it needs to be translated back into the universal physical language, namely Pascal's law. This inversion step is not a simple linear conversion, but a mapping relationship established based on a large amount of experimental data. During the neutron tube production calibration stage, a high-precision vacuum gauge was used in sync with the monitoring algorithm of this invention to accumulate characteristic value data corresponding to different air pressure states, forming a characteristic air pressure mapping database. This invention calls upon the characteristic air pressure mapping database, which acts as a bridge connecting the algorithmic world and the physical world. Through interpolation matching, those complex characteristic values ​​containing thermal efficiency, discharge quality, and temperature effects are restored to the simplest and most intuitive real-time air pressure values, making the air pressure monitoring results have both the scientific depth of the algorithm and the intuitiveness and universality of engineering applications.

[0077] Specifically, based on the characteristic pressure mapping relationship, the corrected pressure value is converted into a real-time physical pressure value, including:

[0078] The system retrieves pre-acquired characteristic pressure mapping data, uses the corrected pressure value as the index key input, and outputs the real-time physical pressure value inside the neutron tube through an interpolation matching algorithm.

[0079] It should be noted that the optimal operating pressure of the neutron tube is a relatively narrow window. Within this range, the ionization efficiency of the ion source is the highest, the neutron yield is the largest, and the insulation risk is the lowest. Once it deviates from this range, either the yield decreases, affecting the quality of logging data, or it causes high-pressure breakdown, damaging the instrument. Traditional PID control often oscillates due to feedback signal lag or noise, i.e., it repeatedly adjusts between underpressure and overpressure. This poses a significant danger for hydrogen storage tanks with high thermal inertia. This invention, based on the inverted real-time physical pressure value, adopts an interval comparison strategy to quickly lock onto the current pressure state.

[0080] Preferably, based on the real-time physical pressure value, a control command is generated to increase, decrease, or maintain the pressure, including:

[0081] The system retrieves the optimal operating pressure range from the database and compares the real-time physical pressure value with the optimal operating pressure range. If the real-time physical pressure value is to the left of the optimal operating pressure range, the system generates a pressure increase regulation command. If the real-time physical pressure value is to the right of the optimal operating pressure range, the system generates a pressure decrease regulation command. If the real-time physical pressure value is within the optimal operating pressure range, including the range boundary, the system maintains the current hydrogen storage tank current.

[0082] It's important to note that, as the final step in the monitoring and control closed loop, command execution and data output are equally crucial. The current adjustment of the hydrogen storage tank requires extreme precision, as temperature changes affect resistance at the milliohm level but have an exponential impact on gas pressure. When executing adjustment commands, the system does not make abrupt adjustments but rather uses a micro-step approach to prevent thermal shock. Simultaneously, real-time physical gas pressure values, external ambient temperature, and thermoelectric conversion quality scores are packaged and uploaded. Engineers can see not only the current gas pressure but also the current gas pressure control efficiency through the thermoelectric conversion quality score. These historical data logs provide valuable first-hand information for subsequent instrument maintenance, lifespan prediction, and fault tracing, upgrading well logging operations from simply viewing results to comprehensive management of the instrument's health status throughout the entire process.

[0083] Specifically, adjusting the hydrogen storage tank current according to the adjustment command includes:

[0084] The system adjusts the heating current of the hydrogen storage tank according to the generated adjustment instructions, and at the same time packages and uploads the real-time physical gas pressure value, the external ambient temperature and the thermoelectric conversion quality score to the host computer display interface to complete this monitoring cycle.

[0085] This completes the real-time monitoring of the neutron tube pressure.

[0086] This invention also discloses a real-time neutron tube pressure monitoring system, including a processor and a memory. The memory stores computer program instructions, which, when executed by the processor, implement a real-time neutron tube pressure monitoring method according to the present invention.

[0087] The system also includes other components well known to those skilled in the art, such as communication buses and communication interfaces, the settings and functions of which are known in the art and will not be described in detail here.

[0088] While this specification has shown and described numerous embodiments of the invention, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Many modifications, alterations, and alternatives will occur to those skilled in the art without departing from the spirit and essence of the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in the practice of this invention.

Claims

1. A method for real-time monitoring of neutron tube gas pressure, characterized in that, include: The basic electrical parameters and environmental data of the neutron tube's working cycle are obtained and statistical calculations are performed to obtain the average voltage of the hydrogen storage device, the average current of the hydrogen storage device, the mean value of the ion source output current, and the standard deviation of the ion source output current. By combining the average voltage and average current of the hydrogen storage device, the amplification of the basic electrothermal power by the state of the hydrogen storage device is analyzed, and the effective thermal thrust index is calculated; the beam fluctuation index is calculated based on the fluctuation of the ion source output flow. By combining the effective thermal thrust index, beam fluctuation index, and the matching degree between the ion source output flow and the target output flow set under the current operating conditions, the thermoelectric conversion quality score is calculated, satisfying the following expression: ； In the formula, Indicates the quality score of thermoelectric conversion; The effective thermal thrust index; The beam fluctuation index; This represents the average output current of the ion source. Set the target output stream for the current operating condition; It is the equilibrium constant; It is the fourth smallest positive number, ensuring that the denominator is not zero; Represents the maximum value function; The thermoelectric conversion quality score is corrected based on the difference between the external ambient temperature and the pre-obtained standard room temperature, and the corrected air pressure value is obtained. Based on the characteristic pressure mapping relationship, the corrected pressure value is converted into a real-time physical pressure value; based on the real-time physical pressure value, an adjustment command is generated to increase, decrease, or maintain the pressure; and the hydrogen storage tank current is adjusted according to the adjustment command.

2. The method for real-time monitoring of neutron tube gas pressure according to claim 1, characterized in that, The process involves acquiring the basic electrical parameters and environmental data of the neutron tube's operating cycle, and performing statistical calculations to obtain the average voltage of the hydrogen storage device, the average current of the hydrogen storage device, the mean value of the ion source output current, and the standard deviation of the ion source output current, including: The system collects in real time the instantaneous values ​​of the voltage across the hydrogen storage device, the instantaneous values ​​of the hydrogen storage device circuit current, the instantaneous values ​​of the ion source output current, and the ambient temperature outside the tube during a single firing cycle; it then performs statistical calculations on the collected data to obtain the average voltage of the hydrogen storage device, the average current of the hydrogen storage device, the mean of the ion source output current, and the standard deviation of the ion source output current.

3. The method for real-time monitoring of neutron tube gas pressure according to claim 1, characterized in that, The effective thermal thrust index satisfies the following expression: ； In the formula, Indicates the effective thermal thrust index; and These are the average voltage and average current of the hydrogen storage device, respectively. The nominal resistance of the hydrogen storage device in the cold state; It is the natural logarithm function; This represents the first smallest positive number, and the denominator is guaranteed to be non-zero.

4. The method for real-time monitoring of neutron tube gas pressure according to claim 1, characterized in that, The beam fluctuation index satisfies the following expression: ； In the formula, Indicates the beam fluctuation index; The standard deviation of the ion source output flow; This represents the average output current of the ion source. This is the maximum designed output flow of the ion source; , The numbers are the second and third smallest positive numbers, ensuring that the denominator is not zero; This represents an exponential function with the natural constant as its base.

5. The method for real-time monitoring of neutron tube gas pressure according to claim 1, characterized in that, Obtaining the corrected air pressure value includes: Obtain the standard room temperature constant and calculate the difference between the external ambient temperature and the standard room temperature constant. Multiply this difference by the thermistor compensation coefficient and add the product to 1, which is recorded as the thermal drift compensation correction term. Multiply the thermoelectric conversion quality score by the thermal drift compensation correction term to obtain the corrected pressure value.

6. The method for real-time monitoring of neutron tube gas pressure according to claim 1, characterized in that, The process of converting the corrected air pressure value into a real-time physical air pressure value includes: The system retrieves pre-acquired characteristic pressure mapping data, uses the corrected pressure value as the index key input, and outputs the real-time physical pressure value inside the neutron tube through an interpolation matching algorithm.

7. The method for real-time monitoring of neutron tube gas pressure according to claim 1, characterized in that, The method of generating pressure-boosting, pressure-reducing, or pressure-maintaining adjustment commands based on real-time physical air pressure values ​​includes: The system retrieves the optimal operating pressure range from the database and compares the real-time physical pressure value with the optimal operating pressure range. If the real-time physical pressure value is to the left of the optimal operating pressure range, the system generates a pressure increase regulation command. If the real-time physical pressure value is to the right of the optimal operating pressure range, the system generates a pressure decrease regulation command. If the real-time physical pressure value is within the optimal operating pressure range, including the range boundary, the system maintains the current hydrogen storage tank current.

8. The method for real-time monitoring of neutron tube gas pressure according to claim 1, characterized in that, The adjustment of the hydrogen storage tank current according to the adjustment command includes: The system adjusts the heating current of the hydrogen storage tank according to the generated adjustment instructions, and at the same time packages and uploads the real-time physical gas pressure value, the external ambient temperature and the thermoelectric conversion quality score to the host computer display interface to complete this monitoring cycle.

9. A real-time neutron tube pressure monitoring system, characterized in that, include: A processor and a memory, wherein the memory stores computer program instructions that, when executed by the processor, implement a real-time neutron tube pressure monitoring method according to any one of claims 1-8.

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