A high-efficiency test method for a neutron pulse type detector and a matching instrument device

Abstract

The application discloses a kind of neutron pulse type detector and the efficient test method of matching instrument device, it is related to reactor nuclear measurement field, its technical scheme key points are: through the efficient test process of unattended, the establishment of multidimensional test model, high-efficiency detector matching interface design, remote diagnosis test method, performance evaluation and report generation model, reduce the transportation cost and manpower cost in test process, improve the accuracy and objectivity of test data acquisition, and greatly improve the timeliness of test report generation;The application can flexibly configure the required number of channels according to actual needs, and unattended throughout the test process, data acquisition retention, data analysis, report generation, instruction issuing, self-diagnosis, fault-tolerant processing, etc. are all realized efficiently, which makes up for the deficiencies of existing test methods, such as high labor cost, low efficiency, low operation standardization, low efficiency, and test results are easily disturbed.

Description

Technical Field

[0001] This invention relates to the field of reactor nuclear measurement, and more specifically, to an efficient testing method for a neutron pulse detector and its supporting instruments. Background Technology

[0002] In critical safety monitoring services for reactor facilities during water filling, refueling, and physical startup, as well as zero-power physics experiments, to ensure nuclear reactor safety during critical monitoring or startup, it is necessary to periodically test the neutron detectors and instruments used in zero-power physics experiments on-pile or at the neutron source, diagnose the health trend of the instruments and equipment, and provide performance evaluation analysis reports and metrological qualification certificates.

[0003] Currently, the existing testing and calibration methods for nuclear pulse neutron detectors involved in reactor core detection are relatively mature. However, these methods mainly target the neutron detectors themselves and lack methods for supporting secondary instruments and equipment. Furthermore, due to numerous limitations, many instruments and equipment undergo comprehensive nuclear testing and calibration only before leaving the factory or being put into use. During subsequent use, there is a lack of regular and standardized testing and calibration. As a result, it is impossible to track the functional performance, technical status, and metrological status of the instruments and equipment in a timely manner. Consequently, the status of nuclear measurement systems and physical experiment monitoring instruments and equipment involved in reactor instrumentation and control cannot be monitored in a timely manner, affecting the operational safety and measurement accuracy of nuclear facilities.

[0004] Therefore, how to research and design an efficient testing method for a neutron pulse detector and its supporting instruments that can overcome the above-mentioned defects is an urgent problem that we need to solve. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide an efficient testing method for neutron pulse detectors and supporting instruments. This method allows for flexible configuration of the required number of channels according to actual needs, and enables unattended operation throughout the entire testing process. It also achieves high efficiency in data acquisition and storage, data analysis, report generation, instruction issuance, self-diagnosis, and fault tolerance.

[0006] The above-mentioned technical objective of the present invention is achieved through the following technical solution: a highly efficient testing method for a neutron pulse detector and its supporting instruments, comprising the following steps:

[0007] S1: By constructing a test process model for the plateau curve and pre-setting configuration parameters and judgment condition boundary values, the system completes parameter setting and adjustment, process status tracking and abnormal data removal, data acquisition and high-pressure plateau curve evaluation and analysis during the high-pressure plateau curve test.

[0008] S2: By constructing a test process model for the discrimination threshold curve and pre-setting configuration parameters and judgment condition boundary values, the parameter setting and adjustment, process status tracking and abnormal data removal, data collection and discrimination threshold curve evaluation and analysis are completed during the discrimination threshold curve test process.

[0009] S3: By recording the current environmental parameters, setting the working high pressure and discrimination threshold in the first two processes, and continuously tracking the process status and identifying abnormal data, data acquisition and stability evaluation analysis for a long period of time, so as to achieve the stability test of the complete set of instruments based on stable neutron flux.

[0010] S4: By evaluating the linearity, neutron sensitivity metrological characteristics, and presence of interval defects of the instrument, the complete set of instruments under the reactor core with dynamically changing neutron flux is tested across the entire start-up source range.

[0011] S5: Map the test data and results from steps S1-S4 into the test report template model, and load the test process record data into the historical database of the corresponding equipment and instruments to complete the test of the equipment and instruments.

[0012] Furthermore, the specific implementation process of the test process model for the plateau curve is as follows:

[0013] The instrument is powered on and running. After the instrument has warmed up and stabilized, a self-test is performed, followed by a background noise test.

[0014] Based on the factory reference parameters of the instrument to be tested and the type of neutron detector, or the parameters of the previous test conclusion, and combined with the instrument's built-in raw nuclear pulse waveform capture function, select and set the working threshold, and configure the detector working high voltage range and high voltage growth step, single neutron counting acquisition duration and number of samplings, stabilization time after high voltage change, and high voltage loading termination conditions for each test channel instrument.

[0015] Select the corresponding plateau curve characteristic calculation formula model, and after the parameters are configured, proceed to the testing and data entry process in this stage.

[0016] Furthermore, the method also includes:

[0017] Dynamically track the nuclear pulse count growth rate N under unit growth high pressure Hv ;

[0018] When N A =0.8*N HvA When N is reached for the first time A The corresponding high voltage is the initial high voltage U of the plateau area. A N HvA The growth rate N of the nuclear pulse count collected under steady-state conditions HvThe count rate value at the first inflection point where the count rate gradually decreases from large to small and approaches 0;

[0019] When N B =1.2*N HvB When N is reached for the first time B The corresponding high-voltage plateau area has an end-point screening threshold U. B N HvB The growth rate N of the nuclear pulse count collected under steady-state conditions Hv The high voltage value at the first inflection point where the voltage gradually increases from small to large;

[0020] Based on the initial high voltage U in the Pingqu area A and endpoint discrimination threshold U B The recommended job selection threshold is determined by a high-pressure job selection algorithm.

[0021] Furthermore, the specific expression for the working high voltage selection algorithm is as follows:

[0022] N Hv = (N2-N1) / △H V21

[0023] U L =U B -U A

[0024] PS = 10 4 *2(N B -N A ) / [(N B +N A (N) B -N A )]

[0025] U = U A +(U B -U A ) / 3

[0026] Where N2 is the count rate at the current threshold voltage, in cps; N1 is the count rate at the previous threshold voltage, in cps; ΔH V21 The difference between two threshold voltages, in V; U L The unit is V; N. B For the terminal voltage U B The count rate, in cps; N A For the terminal voltage U A The count rate is expressed in cps; U is the recommended operating high voltage in V; PS is the slope in % / 100V.

[0027] Furthermore, the method also includes:

[0028] Track nuclear pulse count acquisition and perform dynamic smoothing error statistical fluctuation analysis of the data stream;

[0029] When the statistical error falls within the required range, the instrument system is considered to have entered a stable working state.

[0030] Furthermore, the method also includes:

[0031] The number of neutron pulses collected outside the statistical fluctuation error range is corrected by detecting the instrument status parameters.

[0032] Furthermore, abnormal data is removed through data stream analysis, and gaps are filled using interpolation algorithms before data storage and analysis.

[0033] Furthermore, the implementation process of the test process model for the discrimination threshold curve is as follows:

[0034] The instrument high voltage is set according to the recommended working high voltage, and the detector discrimination threshold range and threshold increase step, single neutron count acquisition duration and number of samplings, stabilization time after threshold change, and threshold loading termination conditions are configured for each test channel instrument.

[0035] Select the corresponding threshold curve characteristic calculation formula model, and after the parameters are configured, proceed to the testing and data entry process in this stage.

[0036] Furthermore, the method also includes:

[0037] Dynamically track the nuclear pulse count growth rate N under the unit growth threshold △v ;

[0038] When N △v ≤N △vA At that time, the turning point from the largest to the smallest value is the initial screening threshold V of the threshold plateau. A N △vA The value of the nuclear pulse count growth rate under steady-state conditions is taken when the threshold plateau region is at its starting point;

[0039] When N △v ≥N △vB At that time, the turning point from the minimum value to the gradually increasing value is the endpoint of the threshold plateau, and the screening threshold V is defined as the threshold value. B N △vB The value of the nuclear pulse count growth rate under steady-state conditions at the end of the threshold plateau region;

[0040] The initial screening threshold V based on the threshold plateau area A and endpoint screening threshold V B The threshold for job screening is determined by a threshold selection algorithm.

[0041] Furthermore, the specific expression for the threshold selection algorithm is as follows:

[0042] N △v =(N2-N1) / △V 21

[0043] V = V A +(V B -V A ) / 3

[0044] Where N2 is the count rate at the current threshold voltage, in cps; N1 is the count rate at the previous threshold voltage, in cps; ΔV 21 V represents the difference between the two threshold voltages, in mV; V is the working discrimination threshold, in mV.

[0045] Furthermore, the method also includes:

[0046] By comparing the low-voltage power supply status values ​​with theoretical values ​​in the common data structure, the power supply operating status is analyzed and judged. At the same time, the statistical distribution of output voltage ripple and noise is calculated, and the dynamic changes of power supply output performance indicators under the operating status are analyzed to diagnose and confirm the low-voltage power supply status of the device. The low-voltage power supply status is obtained through AD analog-to-digital conversion, and the data acquisition and control status is obtained through software running error flags.

[0047] By analyzing and judging the data in the data structure of the actual loaded channel, the high voltage working status and the correlation between high voltage changes and instrument accuracy are obtained; the comprehensive analysis model of the high voltage setting value and the measured value in each channel gives the high voltage working status, and the high voltage output ripple noise distribution is obtained from the high voltage measured value to evaluate the high voltage real-time output quality.

[0048] And / or, perform functional inspections on all channels of the device through a preset self-test signal stream, combine the device's low-voltage power supply operating status and channel high-voltage operating status, give a device status conclusion, quickly locate abnormalities and perform adaptive recovery, or output alarms and provide reasonable solutions.

[0049] Furthermore, the neutron pulse detector is a fully digital neutron detector, specifically:

[0050] Construct a fieldbus that allows for flexible cascading of neutron counter tube detectors, and define the data interface for parameter distribution, loading, and data upload;

[0051] The structural design of the fully digital circuit of the neutron detector is realized through mechanical design, which integrates the high voltage and low voltage supply of the neutron counter tube, the fully digital circuit design of the output signal, and the interface circuit for accessing the bus into an integrated digital adapter.

[0052] Compared with the prior art, the present invention has the following beneficial effects:

[0053] 1. The present invention provides an efficient testing method for a neutron pulse detector and its supporting instruments. The required number of channels can be flexibly configured according to actual needs. The entire testing process is unattended. Data acquisition and storage, data analysis, report generation, instruction issuance, self-diagnosis, and fault tolerance are all highly efficient. This method overcomes the shortcomings of existing testing methods, such as high manpower consumption, low efficiency, low operational standardization, low efficiency, and susceptibility to interference in test results.

[0054] 2. This invention, through the implementation of a digital neutron detector, firstly changes the traditional fully analog architecture of the original neutron detector, which consists of the detector's neutron sensitive section, preamplifier, and high-voltage coaxial cable. It removes the two coaxial cables (high-voltage cable and nuclear pulse signal transmission cable) that affect the overall weight of the detector, reducing the existing weight of the detector by 2 / 3. This improves the mobility and flexibility of the detector at the testing site, especially in the case of multiple neutron detectors conducting tests simultaneously, which will greatly reduce the manpower and time spent in the installation and layout process.

[0055] 3. This invention reduces transportation and labor costs during the testing process by implementing an unattended and efficient testing process, establishing a multi-dimensional testing model, designing an efficient detector matching interface, developing a remote diagnostic testing method, and establishing a performance evaluation and report generation model. At the same time, it improves the accuracy and objectivity of the data obtained during the testing process and greatly enhances the timeliness of the test report generation. Attached Figure Description

[0056] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0057] Figure 1 This is a schematic diagram of the arrangement of the neutron detectors in an embodiment of the present invention;

[0058] Figure 2 This is a schematic diagram of the neutron detector structure in an embodiment of the present invention;

[0059] Figure 3 This is a logic block diagram of the multi-dimensional automatic testing in this embodiment of the invention;

[0060] Figure 4 This is a flowchart of the test data acquisition process in an embodiment of the present invention. Detailed Implementation

[0061] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0062] Traditional testing and calibration methods for nuclear pulse neutron detectors involved in reactor core detection are relatively mature, but they mainly target the neutron detectors themselves and lack methods for supporting secondary instruments. At the same time, current testing and calibration of nuclear pulse neutron detectors are subject to many limitations. Many instruments only undergo comprehensive nuclear testing and calibration before leaving the factory or being put into use. During subsequent use, there is a lack of regular and standardized testing and calibration. Therefore, it is impossible to track the functional performance, technical status, and metrological status of the instruments in a timely manner. The status of nuclear measurement systems and physical experiment monitoring instruments in reactor instrumentation and control cannot be followed up in a timely manner, which affects the operational safety and measurement accuracy of nuclear facilities.

[0063] The reason for the above situation lies in the following deficiencies in the existing testing methods for nuclear pulse neutron detectors used for reactor core detection:

[0064] a. During the testing process, the existing neutron detectors are equipped with coaxial cables of varying lengths from 30m to 80m. The preparation and scene switching processes, such as disassembly, assembly, and layout, consume a lot of manpower and resources. When testing multiple devices simultaneously, due to differences in equipment architecture, interface definition, control methods, etc., each device needs to be operated, recorded, monitored and adjusted separately. This requires additional manpower to track the testing, and the whole process lacks efficient methods and flexibility.

[0065] b. During the testing process, the monitoring and judgment of the status of instruments and equipment, the setting and timing of process parameters, the recording and entry of data, the calculation and analysis of data and the issuance of result reports are all carried out by the testing personnel, and are implemented step by step. The entire testing process is long, inefficient, wasteful of manpower, and prone to human intervention in the test results, introducing human bias and making the testing process lack standardization and objectivity.

[0066] c. Existing testing equipment, due to outdated design or low integration of systems, suffers from several shortcomings, including the inability to store testing data in real time, small and singular amounts of manually recorded data, lack of related auxiliary correction data, and inability to record and retain testing data throughout the entire testing process. This results in cumbersome and time-consuming subsequent data entry and processing, a lack of real-time data correction capabilities, and low efficiency in outputting conclusion reports. Consequently, it fails to meet the needs for refined analysis of instrument and equipment testing, and the ability to iteratively analyze the testing process and uncover data gaps.

[0067] Example: An efficient testing method for a neutron pulse detector and its supporting instruments.

[0068] Step 1

[0069] To facilitate the modular design and easy expansion of the neutron pulse detector and its instrumentation, the instrument's hardware and software design adopts a reconfigurable design concept of "tightly integrated but loosely coupled" for development. This invention first requires the automatic status monitoring and control of the pulse neutron counters. The hardware uses a bus cascading approach to increase or decrease the actual number of neutron counters required. Simultaneously, hardware channel identification technology is used to configure and load the necessary channels, enabling high-voltage control, threshold setting, pulse width setting, baseline setting, and monitoring of fully digital neutron pulse acquisition parameters and status parameters for each neutron counter detector channel.

[0070] like Figure 1 As shown, the technical steps for achieving a fully digital neutron detector are as follows:

[0071] 1) Construct a fieldbus for flexibly cascading neutron counter tube detectors, and agree on the data interface for parameter download and data upload to ensure stable and reliable transmission of detector parameter settings, status data and measurement data during normal instrument operation.

[0072] 2) The structural design of the fully digital circuit of the neutron detector needs to be realized through mechanical design, realizing the integrated design of the digital probe, and the integrated digital adapter to realize the high voltage and low voltage supply to the neutron counter tube, the fully digital circuit design of the output signal, and the interface circuit for accessing the bus.

[0073] like Figure 2 As shown, by realizing the digital neutron detector, the traditional fully analog architecture of the original neutron detector, consisting of the detector's neutron sensitive section, preamplifier, and high-voltage coaxial cable, has been changed. The two coaxial cables (high-voltage cable and nuclear pulse signal transmission cable) that affect the overall weight of the detector have been removed, reducing the existing weight of the detector by 2 / 3. This improves the mobility and flexibility of the detector at the testing site, especially in the case of multiple neutron detectors being tested simultaneously, which will greatly reduce the manpower and time spent in the installation and layout process.

[0074] Furthermore, the absence of long cables for high-voltage power supply and signal transmission eliminates interference from harsh environments along the cable routing path, such as vibration or trampling, electromagnetic radiation, electrostatic induction, and contact reliability issues. These factors can couple into the transmitted nuclear pulse signal through the cable, reducing the signal-to-noise ratio and even rendering the equipment unusable. In addition, high-voltage fluctuations caused by interference can also cause the neutron detector to operate in an unstable state.

[0075] This invention also replaces the main amplifier function and pulse discrimination and display function of the analog instrument architecture in the secondary instrumentation originally located in the main control room with all-digital nuclear pulse technology and integrates them into the neutron detector, realizing digital nuclear pulse discrimination and technology, forming a brand-new all-digital neutron detector. At the same time, data bus communication is added, which can be networked based on the design bus protocol, flexibly configure the number of neutron detector channels to be tested, and interact with the host computer of the testing system to complete data status transmission and control configuration distribution. This overcomes the shortcomings of existing neutron detectors, such as inability to adapt to networking, coarse and scattered data recording, and poor comparability of synchronous operation. On this hardware basis, the efficiency and precision of various testing processes can be greatly improved.

[0076] Step Two

[0077] like Figure 3 As shown, the automatic testing content includes four aspects: high-pressure plateau curve testing and evaluation, discrimination threshold curve testing and evaluation, stability testing and evaluation, and actual reactor testing evaluation. These are carried out in a sequential and progressive manner. The evaluation order of the high-pressure plateau curve and the discrimination threshold curve can be interchanged. Based on this, the high-pressure plateau region range (initial high pressure and cutoff high pressure), plateau width, plateau slope, recommended operating high pressure, discrimination threshold range, and recommended discrimination threshold are obtained as neutron detector configuration parameters for subsequent testing processes.

[0078] The entire testing process in this invention is as follows: First, by constructing a testing process model for the plateau curve, pre-setting configuration parameters, judgment condition boundary values, etc., the parameter setting and adjustment, process status tracking and abnormal data removal, data acquisition, and high-pressure plateau curve evaluation and analysis are completed during the high-pressure plateau curve test. Then, by constructing a testing process model for the discrimination threshold curve, pre-setting configuration parameters, judgment condition boundary values, etc., the parameter setting and adjustment, process status tracking and abnormal data removal, data acquisition, and discrimination threshold curve evaluation and analysis are completed during the discrimination threshold curve test. The stability test is a stability test process for a complete set of instruments based on a specific neutron source (stable neutron flux). It records the current environmental parameters, sets the operating high pressure and discrimination threshold in the first two processes, and continuously tracks the process status and identifies abnormal data, acquires data, and performs stability evaluation and analysis over a long period. The on-reactor test is a test of a complete set of instruments under a reactor core with dynamically changing neutron flux (from the natural background to the neutron flux that saturates the neutron detector) across the entire start-up source range, evaluating the instrument's linearity, neutron sensitivity metrological characteristics, and the presence of interval defects.

[0079] Automatic switching analysis and judgment, self-diagnosis throughout the test, and abnormal data identification and removal are integrated into the four stages of the test process. Automatic switching analysis and judgment refers to functions such as when to read data, when to adjust the high voltage or threshold according to steps, and when to terminate the increase of high voltage and end the current process during the test. Self-diagnosis throughout the test monitors the low-voltage and high-voltage output status (fluctuations in load current and output voltage, deviations from set values, etc.) in real time during the test to evaluate the health status of the analysis instruments and equipment, and to assist in evaluating the impact of current data interference. In addition, the high-voltage fluctuation method is used to check the reliability and correctness of the instrument and equipment connections.

[0080] (1) Constructing a test process model and analysis and judgment of the plateau curve

[0081] The key feature of this invention in plateau curve characteristic testing is to achieve online identification, judgment, collection and storage of the required test data without human intervention, and to automatically input the data into a preset calculation and analysis model to quickly obtain the required plateau curve characteristic results.

[0082] The steps for implementing the plateau curve testing process model are as follows: The instrument is powered on and, after warm-up and stabilization, a self-test is performed. The instrument's background noise is then tested. Based on the factory reference parameters for the instrument under test and the type of neutron detector, or the parameters from the previous test, and combined with the instrument's built-in raw nuclear pulse waveform capture function, the working threshold is selected and set. The detector's high-voltage range and high-voltage growth step, single neutron count acquisition duration and number of samples, stabilization time after high-voltage changes, and high-voltage loading termination conditions are defined and configured for each test channel. A suitable plateau curve characteristic calculation formula model is selected. Once the parameters are configured, the testing and data entry process for this stage begins.

[0083] Taking the BF3 neutron proportional counter tube as an example, the threshold is selected as 250mV, and its high voltage loading range is 0~2500V. The high voltage growth step is set to 50V, which can be selected as an integer multiple of 25V. The smaller the step, the more refined the plateau curve is obtained. The selection is based on factors such as the test duration and progress requirements, and the accuracy of the results. The operation process is as follows: ① Set up the neutron source, detector, and special physics experiment instruments according to... Figure 1 Install and fix the instrument in the layout shown. Power on the instrument and warm it up for 20 minutes to ensure that all functions are operating normally. ② Set the relevant instrument parameters, including a discrimination threshold of 250mV and a sampling time of 100s (sampling 10 times, with each sampling lasting 10s). The sampling duration is selected based on the neutron source intensity; extend the sampling time for low neutron source intensity and shorten it for high neutron source intensity, ensuring that the cumulative neutron count rate for each sampling period is maintained at 10. 3The following parameters are used to determine the order of magnitude (under normal operating conditions) to reduce the impact of statistical fluctuations in radioactivity measurements on the results; stabilization time is 180s; high voltage increment is 50V; high voltage setting range is 0-2500V; stable reading model (abnormal data with deviations exceeding 20% ​​in the same data set are identified, marked, associated, confirmed, and removed, and data is corrected and replaced); plateau boundary value judgment model (the smaller the high voltage increment, the more accurate the boundary value); high voltage increase termination judgment condition (the high voltage is stopped when the count rate increases to 120% of the count rate at the plateau high voltage); ③ Entering unattended testing mode, the first step is to set the high voltage to 0V, stabilize for 180s, start removing abnormal data and record and store 10 sets of neutron count rates for 100s, and calculate... The first step involves importing the 10-count average into the analysis model input interface. The second step increases the voltage to 50V, stabilizes for 180 seconds, begins removing outlier data, and records and stores 10 sets of neutron count rates over 100 seconds. The 10-count average is then calculated and imported into the analysis model input interface. Subsequent steps three through fifty (n = |2500 / 50| = 50, or replacing the denominator 2500V with the voltage increase termination value) all execute the previous operations (stabilizing for 180 seconds, removing outlier data, recording and storing 10 sets of neutron count rates over 100 seconds, calculating the 10-count average, and importing it into the analysis model input interface). At this point, data entry for this stage is complete, and the input data for the plateau curve characteristic calculation model is ready. The data flow is then tested. Figure 4 As shown; ④ The high-voltage plateau curve of the neutron detector required will be plotted in real time by using the pre-set plateau curve characteristic calculation model, and the high-voltage working plateau region and its boundary value of the BF3 neutron counter tube will be determined simultaneously. The plateau length and plateau inclination performance indicators will be calculated, and the recommended working discrimination threshold will be given.

[0084] High-voltage termination addition algorithm: Dynamically tracking the nuclear pulse count growth rate N under unit-increasing high voltage. Hv When N A =0.8*N HvA When N is reached for the first time A The corresponding high voltage is the initial high voltage U of the plateau area. A N HvA The growth rate N of the nuclear pulse count collected under steady-state conditions Hv The count rate value at the first inflection point where it gradually decreases from large to close to 0; when N B =1.2*N HvB When N is reached for the first time B The corresponding high-voltage plateau area has an end-point screening threshold U. B N HvB The growth rate N of the nuclear pulse count collected under steady-state conditions Hv The high-pressure value at the first inflection point where it gradually increases from small to large; based on the initial high-pressure U of the plateau area. A and endpoint discrimination threshold U BThe recommended job selection threshold is determined by a high-pressure job selection algorithm.

[0085] The specific expression for the high-voltage selection algorithm is as follows:

[0086] N Hv = (N2-N1) / △H V21

[0087] U L =U B -U A

[0088] PS = 10 4 *2(N B -N A ) / [(N B +N A (N) B -N A )]

[0089] U = U A +(U B -U A ) / 3

[0090] Where N2 is the count rate at the current threshold voltage, in cps; N1 is the count rate at the previous threshold voltage, in cps; ΔH V21 The difference between two threshold voltages, in V; U L The unit is V; N. B For the terminal voltage U B The count rate, in cps; N A For the terminal voltage U A The count rate is expressed in cps; U is the recommended operating high voltage in V; PS is the slope in % / 100V.

[0091] Counting stability algorithm: Track the nuclear pulse count acquisition, perform dynamic smoothing error statistical fluctuation analysis of the data stream, and when the statistical error falls within the required range, the instrument system is considered to have entered a stable working state.

[0092] Neutron counting preprocessing model: During the stability observation process, the neutron source is stable, the instrument parameters are fixed, and the number of neutron pulses collected should also be within the range of statistical fluctuation error. If it exceeds the range, it is caused by external interference or the stability of the instrument itself. Therefore, it can be corrected by detecting the instrument status parameters. At the same time, abnormal data is removed by data stream analysis, and gaps are filled by interpolation algorithm before data storage and analysis.

[0093] (2) Constructing a test process model and analysis and judgment for the screening threshold curve

[0094] To obtain the threshold characteristics of the neutron pulse counter and its supporting instruments, it is necessary to match the threshold range and interval threshold step of the loaded detector under a specific operating high voltage, the single neutron counting acquisition time, and to configure all the channels in use according to actual needs. Data acquisition will be carried out during the test process, and the threshold plateau, plateau width, and automatic termination threshold curve test of the neutron counter will be determined by the acquired data and analysis and judgment model.

[0095] After completing the first part of the test, the second part, the threshold test, will begin. The steps for implementing the threshold curve test model are as follows: Based on the recommended working high voltage in the first step, set the instrument high voltage, clarify and configure the detector discrimination threshold range and threshold growth step of each test channel instrument, the single neutron count acquisition duration and number of samples, the stabilization time after threshold change, the threshold loading termination condition, and other parameters. Select a suitable threshold curve characteristic calculation formula model. After the parameters are configured, proceed to the test and data entry process in this stage.

[0096] Taking the BF3 neutron proportional counter tube as an example, the high voltage is selected as the recommended working high voltage, and its threshold loading range is 0-1000mV. The threshold increase step is set to 50mV, which can be selected as an integer multiple of 25mV. The smaller the step, the more refined the threshold curve is. The selection is based on factors such as the test duration, progress requirements, and result accuracy. The operation process is as follows: ① After completing the first part, there is no need to shut down and restart to continue the test. Set the relevant instrument parameters, set the working high voltage to the recommended working high voltage, and the sampling time to 100s (sampling 10 times, counting for 10s each time. The selection of the sampling time is based on the neutron source intensity. When the neutron source intensity is low, the sampling time is extended, and vice versa, to ensure that the cumulative neutron count rate of each sampling time period should be guaranteed to be 10. 3Order of magnitude (under normal working conditions, to reduce the impact of statistical fluctuations in radioactivity measurement on the results), stabilization time 180s, threshold increment step 50mV, threshold setting range 0-1000mV, stable reading model (identifying, marking, confirming and removing abnormal data with deviations exceeding 20% ​​in the same data set, and correcting and replacing the data), plateau boundary value judgment model (the smaller the threshold increment, the more accurate the boundary value), threshold increase termination judgment condition (stopping further increase of high voltage when the count rate increases to 150% of the count rate in the plateau area); ③ Entering unmanned test mode, the first step is to set the threshold to 0mV, stabilize for 180s, start removing abnormal data and record and store 10 sets of neutron count rates under 100s, calculate the 10 count average values ​​and import them into the analysis model input interface; the second step is to set the threshold Increase to 50mV, stabilize for 180s, begin removing abnormal data and record and store 10 sets of neutron count rates over 100s, calculate the 10-count average and import it into the analysis model input interface; in subsequent steps 3 to 20 (n=|1000 / 50|=20), all the previous operations are performed (stabilize for 180s, begin removing abnormal data and record and store 10 sets of neutron count rates over 100s, calculate the 10-count average and import it into the analysis model input interface). At this point, the data entry for this step is complete, and the input data for the threshold curve characteristic calculation model is ready; ④ The required neutron detector discrimination threshold plateau curve will be plotted in real time through the preset threshold curve characteristic calculation model, and the discrimination threshold plateau region and its boundary values ​​of the BF3 neutron counter tube and supporting instruments will be determined simultaneously, and the recommended discrimination threshold setting value will be given.

[0097] The algorithm for terminating the addition based on the threshold is: dynamically tracking the nuclear pulse count growth rate N under a unit growth threshold. △v When N △v ≤N △vA At that time, the turning point from the largest to the smallest value is the initial screening threshold V of the threshold plateau. A N △vA The value of the nuclear pulse count growth rate under steady-state conditions when N is at the starting point of the threshold plateau region; △v ≥N △vB At that time, the turning point from the minimum value to the gradually increasing value is the endpoint of the threshold plateau, and the screening threshold V is defined as the threshold value. B N △vB The value of the nuclear pulse count growth rate in the steady state at the end of the threshold plateau region; the initial discrimination threshold V based on the threshold plateau region. A and endpoint screening threshold V B The threshold for job screening is determined by a threshold selection algorithm.

[0098] By tracking the change in count rate under the threshold value of the search unit segment by segment, the refined high-pressure interval can more accurately find the start and end points of the plateau curve plateau area, and can determine the interval and boundary value according to different selection modes.

[0099] The specific expression for the threshold selection algorithm is as follows:

[0100] N △v =(N2-N1) / △V 21

[0101] V = V A +(V B -V A ) / 3

[0102] Where N2 is the count rate at the current threshold voltage, in cps; N1 is the count rate at the previous threshold voltage, in cps; ΔV 21 V represents the difference between the two threshold voltages, in mV; V is the working discrimination threshold, in mV.

[0103] (3) The present invention also analyzes and judges the working state of the power supply by comparing the low-voltage power supply status value with the theoretical value in the common data structure, and calculates the statistical distribution of the output voltage ripple and noise, and analyzes the dynamic changes of the power supply output performance index under the working state of the power supply, so as to diagnose and confirm the low-voltage power supply status of the device, and facilitate the correlation analysis of subsequent occasional events; the low-voltage power supply status is obtained through AD analog-to-digital conversion, and the data acquisition control status is obtained through software running error flags.

[0104] Secondly, by analyzing the data within the actual loaded channel data structure, the high-voltage operating status and the correlation between high-voltage changes and instrument accuracy are obtained. A comprehensive analysis model of the high-voltage setting value and measured value within each channel provides the high-voltage operating status. The high-voltage output ripple noise distribution is obtained from the measured high-voltage values ​​to assess the real-time high-voltage output quality, and it also facilitates correlation analysis of occasional events. The channel operating status is confirmed through single-channel analysis results, and anomalies (individual or common) are located by analyzing the operating status results of all online channels, facilitating rapid decision-making for the diagnostic model.

[0105] Finally, the device performs functional inspections on all channels using a preset self-test signal stream. Combining the device's low-voltage power supply status and the channel's high-voltage status, it quickly provides a conclusion on the device's status and has the ability to quickly locate anomalies and perform adaptive recovery, or output alarms and provide reasonable solutions.

[0106] Historical tracking of all detectors under test is required, along with comparative analysis of detector performance at the same point in time. Statistical analysis of data from all previous tests is also necessary to analyze the trends in detector performance and predict detector lifespan.

[0107] Step Two

[0108] The stability test aims to evaluate the instrument and equipment under a relatively long period of operation, focusing on a constant measurement target, and to obtain the instrument's measurement accuracy, health stability, failure rate, and environmental adaptability throughout the test process. In addition, it can be compared with the parameter indicators of the previous test cycle to obtain the decay trend and decay amount of relevant performance indicators.

[0109] After completing the above tests, based on the recommended working high voltage setting of the instrument, the recommended threshold setting of the discrimination threshold, the test duration and sampling interval of the detector of each test channel instrument, the single neutron count acquisition duration and sampling number, the abnormal data rejection judgment threshold, and the stable curve characteristic calculation formula model, the test and data entry process of this stage will be carried out.

[0110] Taking the BF3 neutron proportional counter tube as an example, the high voltage is set to the recommended operating high voltage, and the threshold is set to the recommended discrimination threshold. The operation process is as follows: ① After completing the second part, there is no need to shut down and restart to continue the test. Set the relevant instrument parameters, the test time to 48 hours, the sampling interval to 0.5 hours (selected according to actual needs), and the sampling time for each sample to 100 seconds (10 samples, each 10 seconds of counting. The selection of the sampling time depends on the neutron source intensity. When the neutron source intensity is low, the sampling time is extended, and vice versa, to ensure that the cumulative neutron count rate of each sampling period should be maintained at 10. 3 To reduce the impact of statistical fluctuations in radioactivity measurements on the results, the data is preprocessed using a stable reading model (identifying, marking, and removing outliers with deviations exceeding 20% ​​within the same data set, followed by data correction and replacement) to obtain readings; ③ Entering the unmanned testing mode, the first step is to remove outliers and record and store 10 sets of neutron count rates for 100 seconds at the start of the test, and calculate the average of the 10 counts and import it into the analysis model input interface; the second step is to remove outliers and record and store 10 sets of neutron count rates for 100 seconds 0.5 hours after the test, and calculate the average of the 10 counts and import it into the analysis model input interface. The 10-count average value is imported into the analysis model input interface; in subsequent steps 3 to 96 (n = |48 / 0.5| = 96), the previous operations are performed (starting to remove abnormal data and recording and storing 10 sets of neutron count rates over 100 seconds, calculating the 10-count average value and importing it into the analysis model input interface). At this point, the data entry for this step is complete, and the input data for the stability characteristic calculation model of the steady-state neutron count rate curve is ready; ④ The required neutron detection neutron count rate stability curve will be plotted in real time through the preset stability characteristic calculation model, and the dispersion of the neutron count rate during this process will be determined to evaluate the stability. By retrieving the relevant test performance indicators from the previous test cycle from the database, and comparing them with the corresponding indicators obtained this time, the rate of change of different indicators is calculated to obtain the comprehensive stability of the instrument system in the previous test cycle.

[0111] The data from this process is fully retained and analyzed. The number of abnormal nuclear pulse count growth rates is counted, and the location and analysis are conducted to determine whether the abnormality is caused by the instrument's own health status, external interference factors, or changes in environmental factors, and to evaluate the overall status of the instrument.

[0112] Step 3

[0113] The on-chip testing objective is to evaluate the performance of instruments and equipment under real-world operating conditions. The neutron flux in the reactor core start-up source region can cover the measurement range of the instruments and equipment (0–10). 6 (cps), and this process is tested without blind spots in the continuous variation range. At the same time, it can also be calibrated by relative comparison using a calibrated neutron detector of the same model, and the equipment under test can be calibrated by using a standard neutron counter tube to obtain real quantitative performance indicators.

[0114] After completing the above tests, the detector must first be installed on the reactor core to be tested, and the test conditions must be prepared. The high pressure and discrimination threshold of the instrument must be determined as described above. The single neutron count acquisition time and sampling number of the detector of each test channel instrument must be clarified and configured, as well as the threshold for judging abnormal data rejection. After the parameters are configured, the test and data entry process of this stage will begin.

[0115] Taking the BF3 neutron proportional counter tube as an example, the operation process is as follows: ① Start the instrument, set the parameters, and after the instrument is working normally, preheat for 20 minutes. Track the reactor core startup process, track and acquire the neutron count rate in real time and save it. Stabilize the reading model (identify, mark, confirm and remove abnormal data with a sudden deviation of more than 50% in the neutron count rate under a specific control rod position, and correct and replace the data, except for short cycles); ③ Enter the unmanned test mode. In the first step, after raising the rod position for the first time and stabilizing, start to remove abnormal data and record and store 10 sets of neutron count rates for 100 seconds, calculate the average of 10 counts and import it into the analysis model input interface; in the second step, after raising the rod position for the second time and stabilizing, start to remove abnormal data and record and store 100 seconds of data. The neutron count rate of 10 sets under s is calculated, and the 10-count average value is imported into the analysis model input interface; in subsequent steps 3 to n (the number of times after the reactor subcriticality is greater than 0.996), the previous operations are performed (starting to remove abnormal data and recording and storing the neutron count rate of 10 sets under 100s, calculating the 10-count average value and importing it into the critical extrapolation model input interface); ④ Continue to track and record the neutron count rate during the start-up process, guiding the reactor power level to enter the intermediate measurement zone. At this time, the detector is close to the saturation zone and will soon exceed the effective measurement range. Plot the neutron count rate distribution curve of the whole process, and compare the trend consistency of the neutron tube count rate curve, whether there is any power outage or missing data in the middle, and whether there are any faults or abnormal phenomena in the process.

[0116] Using the test data and results from the previous sections, the data is mapped and populated into the test report template model. At the same time, the data recorded throughout the test process is loaded into the historical database of the equipment to ensure that the information is accurate, comprehensive, and traceable, such as the test environment status, condition preparation status, test equipment number and identification, test time, participants, test content, cross-sectional and cross-sectional comparative analysis reference, conclusions, and other modules.

[0117] Under the demanding and precise testing model, the original methods are even less capable of completing the task. Only by using instruments and devices under the pre-set process model in an unattended manner, as described in this invention, can the task be completed. At the same time, when the adaptive strategy cannot switch to solve the emergency situation, the device will send alarm information to the communication terminal of the on-duty personnel via Ethernet, reminding the staff to take emergency measures and return to the site in time to deal with the anomaly, so as to ensure the smooth progress of the test.

[0118] Working principle: This invention can flexibly configure the required number of channels according to actual needs, and the entire testing process is unattended. The entire process of data collection and retention, data analysis, report generation, instruction issuance, self-diagnosis, and fault tolerance are all highly efficient, making up for the shortcomings of existing testing methods such as high manpower consumption, low efficiency, low operational standardization, low efficiency, and easy interference of test results.

[0119] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0120] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0121] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0122] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0123] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An efficient testing method for a neutron pulse detector and its supporting instruments, characterized in that, Includes the following steps: S1: By constructing a test process model for the plateau curve and pre-setting configuration parameters and judgment condition boundary values, the system completes parameter setting and adjustment, process status tracking and abnormal data removal, data acquisition and high-pressure plateau curve evaluation and analysis during the high-pressure plateau curve test. S2: By constructing a test process model for the discrimination threshold curve and pre-setting configuration parameters and judgment condition boundary values, the parameter setting and adjustment, process status tracking and abnormal data removal, data collection and discrimination threshold curve evaluation and analysis are completed during the discrimination threshold curve test process. S3: By recording the current environmental parameters, setting the working high pressure and discrimination threshold in the first two processes, and continuously tracking the process status and identifying abnormal data, data acquisition and stability evaluation analysis for a long period of time, so as to achieve the stability test of the complete set of instruments based on stable neutron flux. S4: By evaluating the linearity, neutron sensitivity metrological characteristics, and presence of interval defects of the instrument, the complete set of instruments under the reactor core with dynamically changing neutron flux is tested across the entire start-up source range. S5: Map the test data and results from steps S1-S4 into the test report template model, and simultaneously load the entire test process record data into the historical database of the corresponding equipment and instrument, thus completing the test of the equipment and instrument. The method also includes: Dynamically track the nuclear pulse count growth rate N under unit growth high pressure Hv ; When N A =0.8*N HvA When N is reached for the first time A The corresponding high voltage is the initial high voltage U of the plateau area. A N HvA The growth rate N of the nuclear pulse count collected under steady-state conditions Hv The count rate value at the first inflection point where the count rate gradually decreases from large to small and approaches 0; When N B =1.2*N HvB When N is reached for the first time B The corresponding high voltage is the terminal high voltage U of the plateau area. B N HvB The growth rate N of the nuclear pulse count collected under steady-state conditions Hv The high voltage value at the first inflection point where the voltage gradually increases from small to large; Based on the initial high voltage U in the Pingqu area A and the endpoint high voltage U B The recommended job selection threshold is determined by a high-pressure job selection algorithm.

2. The efficient testing method for a neutron pulse detector and its supporting instruments as described in claim 1, characterized in that, The specific implementation process of the test process model for the plateau curve is as follows: The instrument is powered on and running. After the instrument has warmed up and stabilized, a self-test is performed, followed by a background noise test. Based on the factory reference parameters of the instrument to be tested and the type of neutron detector, or the parameters of the previous test conclusion, and combined with the instrument's built-in raw nuclear pulse waveform capture function, select and set the working threshold, and configure the detector working high voltage range and high voltage growth step, single neutron counting acquisition duration and number of samplings, stabilization time after high voltage change, and high voltage loading termination conditions for each test channel instrument. Select the corresponding plateau curve characteristic calculation formula model, and after the parameters are configured, proceed to the testing and data entry process in this stage.

3. The efficient testing method for a neutron pulse detector and its supporting instruments as described in claim 2, characterized in that, The specific expression for the working high voltage selection algorithm is as follows: N Hv =(N2-N1) / △H V21 IN L =U B -IN A PS=10 4 *2(N B -N A ) / [(N B +N A )(N B -N A )] U=U A +(In B -IN A ) / 3 Where N2 is the count rate at the current threshold voltage, in cps; N1 is the count rate at the previous threshold voltage, in cps; ΔH V21 The difference between two threshold voltages, in V; U L The unit is V; N. B For the terminal voltage U B The count rate, in cps; N A For the terminal voltage U A The count rate is expressed in cps; U is the recommended operating high voltage in V; PS is the slope in % / 100V.

4. The efficient testing method for a neutron pulse detector and its supporting instruments as described in claim 2, characterized in that, The method also includes: Track nuclear pulse count acquisition and perform dynamic smoothing error statistical fluctuation analysis of the data stream; When the statistical error falls within the required range, the instrument system is considered to have entered a stable working state.

5. The efficient testing method for a neutron pulse detector and its supporting instruments as described in claim 2, characterized in that, The method also includes: The number of neutron pulses collected outside the statistical fluctuation error range is corrected by detecting the instrument status parameters. Furthermore, abnormal data is removed through data stream analysis, and gaps are filled using interpolation algorithms before data storage and analysis.

6. The efficient testing method for a neutron pulse detector and its supporting instruments as described in claim 1, characterized in that, The specific implementation process of the test process model for the discrimination threshold curve is as follows: The instrument high voltage is set according to the recommended working high voltage, and the detector discrimination threshold range and threshold increase step, single neutron count acquisition duration and number of samplings, stabilization time after threshold change, and threshold loading termination conditions are configured for each test channel instrument. Select the corresponding threshold curve characteristic calculation formula model, and after the parameters are configured, proceed to the testing and data entry process in this stage.

7. The efficient testing method for a neutron pulse detector and its supporting instruments as described in claim 6, characterized in that, The method also includes: Dynamically track the nuclear pulse count growth rate N under the unit growth threshold △v ; When N △v ≤N △vA At that time, the turning point from the largest to the smallest value is the initial screening threshold V of the threshold plateau. A N △vA The value of the nuclear pulse count growth rate under steady-state conditions is taken when the threshold plateau region is at its starting point; When N △v ≥N △vB At that time, the turning point from the minimum value to the gradually increasing value is the endpoint of the threshold plateau, and the screening threshold V is defined as the threshold value. B N △vB The value of the nuclear pulse count growth rate under steady-state conditions at the end of the threshold plateau region; The initial screening threshold V based on the threshold plateau area A and endpoint screening threshold V B The threshold for job screening is determined by a threshold selection algorithm.

8. The efficient testing method for a neutron pulse detector and its supporting instruments as described in claim 7, characterized in that, The specific expression for the threshold selection algorithm is as follows: N △v =(N2-N1) / △V 21 V=V A +(V B -V A ) / 3 Where N2 is the count rate at the current threshold voltage, in cps; N1 is the count rate at the previous threshold voltage, in cps; ΔV 21 V represents the difference between the two threshold voltages, in mV; V is the working discrimination threshold, in mV.

9. The efficient testing method for a neutron pulse detector and its supporting instruments as described in claim 1, characterized in that, The method also includes: By comparing the low-voltage power supply status values ​​with theoretical values ​​in the common data structure, the power supply operating status is analyzed and judged. At the same time, the statistical distribution of output voltage ripple and noise is calculated, and the dynamic changes of power supply output performance indicators under the operating status are analyzed to diagnose and confirm the low-voltage power supply status of the device. The low-voltage power supply status is obtained through AD analog-to-digital conversion, and the data acquisition and control status is obtained through software running error flags. By analyzing and judging the data in the data structure of the actual loaded channel, the high voltage working status and the correlation between high voltage changes and instrument accuracy are obtained; the comprehensive analysis model of the high voltage setting value and the measured value in each channel gives the high voltage working status, and the high voltage output ripple noise distribution is obtained from the high voltage measured value to evaluate the high voltage real-time output quality. And / or, perform functional inspections on all channels of the device through a preset self-test signal stream, combine the device's low-voltage power supply operating status and channel high-voltage operating status, give a device status conclusion, quickly locate abnormalities and perform adaptive recovery, or output alarms and provide reasonable solutions.

10. The efficient testing method for a neutron pulse detector and its supporting instruments as described in claim 1, characterized in that, The neutron pulse detector is a fully digital neutron detector, specifically: Construct a fieldbus that allows for flexible cascading of neutron counter tube detectors, and define the data interface for parameter distribution, loading, and data upload; The structural design of the fully digital circuit of the neutron detector is realized through mechanical design, which integrates the high voltage and low voltage supply of the neutron counter tube, the fully digital circuit design of the output signal, and the interface circuit for accessing the bus into an integrated digital adapter.

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