Reactor reactivity measurement method and system

Abstract

The invention discloses a reactor reactivity measurement method and system, and relates to the field of reactor nuclear measurement, and the technical scheme is characterized in that weak current-to-voltage and multi-channel filtering processing is carried out on a detector current signal; conditioning the rod position signal of the to-be-detected rod position; dynamically configuring a sampling rate according to a measurement range and a measurement method of the multiple paths of first voltage signals, and acquiring a conditioning conversion gear and a plurality of weighting coefficients; carrying out fusion processing on the plurality of weighting coefficients and the plurality of paths of first current signals; and performing time synchronization processing on the synthesized current value according to the rod position conditioning signal to obtain a corrected synthesized current value. According to the method, all-digital signal conditioning and synchronous acquisition of detector signal current and to-be-measured rod position signals are adopted, the precision of a parameter correction model is improved, meanwhile, multi-filtering path conditioning and weighted correction are adopted, and correction data matched with a data measurement method can be obtained; in addition, dynamic loading of configuration parameters is adopted, and micro-current signal conditioning, acquisition and correction parameter initialization are achieved.

Description

Technical Field

[0001] The present invention relates to the field of reactor nuclear measurement, and more specifically, to a reactor reactivity measurement method and system. Background Art

[0002] In the core design of reactor physics, corresponding experiments are required for technical verification; the neutron flux measurement, power measurement, neutron noise, reactivity parameter measurement technology involved in the reactor zero-power physics experimental method all use the current type γ compensation ionization chamber as the detector, and use the corresponding data analysis model to obtain the target parameters to be measured. The power measurement and power protection device, digital reactivity meter, absolute power meter, etc. in the power reactor or zero-power device measures the neutron changes in the reactor outside the reactor, and collects data by conditioning the weak current signal of the reaction neutron changes and combining with the corresponding model algorithm to realize the neutron flux level, power level, reactivity and other parameter values ​​of the reactor.

[0003] Existing neutron weak current type reactor physics experiment reactivity measurement instruments are mostly designed with single-channel or dual-channel integrated architecture, and are mostly used for zero-power physics tests of new research reactor cores and smaller marine power cores. Signals are usually obtained by attaching neutron detectors. They include neutron detectors, long signal (or high-voltage) cables, and instrument measurement hosts. Their biggest drawbacks are the distributed capacitance of long cables and the introduction of wiring line noise interference, which will cause the signal-to-noise ratio and time response characteristics to deteriorate. Their single instrument design cannot meet the needs of multi-channel coupled measurement and analysis test scenarios; or they are customized to match the reactor core reactivity measurement of a certain special test scenario (such as nuclear power plant power core), which mainly focuses on data acquisition and subsequent data calculation and analysis. Usually, the neutron detector microcurrent signal of its nuclear measurement system is obtained through a communication bus, and it shares a signal source with the nuclear power plant reactor instrumentation and control system. The parameter characteristics of its signal source depend on the configuration of the instrumentation and control system. In most cases, it is impossible to carry out the expansion needs of diversified test and analysis according to the test requirements, and at the same time, key technical performance indicators cannot be arbitrarily optimized and changed (such as data signal-to-noise ratio, response time, filter time response, data sampling frequency, etc.).

[0004] Therefore, how to research and design a reactor reactivity measurement method and system that can overcome the above-mentioned defects is a problem that we urgently need to solve. Summary of the invention

[0005] In order to solve the deficiencies in the prior art, the purpose of the present invention is to provide a reactor reactivity measurement method and system, which adopts full digital signal conditioning and synchronous acquisition of detector signal current and rod position signal to be measured to improve the accuracy of parameter correction model, and adopts multi-filter path conditioning and weighted correction to obtain corrected data for matching data measurement method; in addition, dynamic loading of configuration parameters is adopted to realize microcurrent signal conditioning, acquisition, and initialization of correction parameters.

[0006] The above technical objectives of the present invention are achieved through the following technical solutions:

[0007] In a first aspect, a method for measuring reactor reactivity is provided, comprising the following steps:

[0008] Performing weak current-to-voltage conversion and multi-channel filtering processing on the collected detector current signal to obtain multiple first voltage signals;

[0009] Conditioning the collected rod position signal of the rod position to be measured to obtain a rod position conditioning signal;

[0010] Performing analog-to-digital conversion on the multiple first voltage signals and the rod position conditioning signals respectively to obtain corresponding digital signals;

[0011] Dynamically configure the sampling rate, acquisition conditioning conversion gear and multiple weighting coefficients according to the measurement range and measurement method of the multiple first voltage signals represented by digital signals;

[0012] Converting the multiple first voltage signals into multiple first current signals, and fusing the multiple weighting coefficients with the multiple first current signals to obtain a synthesized current value;

[0013] The synthetic current value is processed in time synchronization according to the rod position conditioning signal to obtain a corrected synthetic current value, and the reactivity measurement and analysis is realized based on the corrected synthetic current value.

[0014] Furthermore, the method also includes:

[0015] The actual sampling rate of the multiple first voltage signals and the rod position conditioning signals during analog-to-digital conversion is adjusted in real time according to the configured sampling rate.

[0016] Furthermore, the method also includes:

[0017] The current operating sample rate setting for the analog-to-digital conversion is adjusted in real time according to the configured sample rate.

[0018] Furthermore, the process of obtaining the synthetic current value is specifically as follows:

[0019] Multiplying the weighting coefficient with the first current signal converted from the output corresponding to the corresponding filter channel to obtain a second current value;

[0020] The multiple second current values ​​are summed to obtain a composite current value.

[0021] Furthermore, the process of obtaining the modified synthetic current value is specifically as follows:

[0022] According to the initial sampling time of the rod position conditioning signal and the rod position interval value, the spatial correction factor at the corresponding moment is matched to obtain the spatial correction factor sequence;

[0023] Each sampling rod site is used as a link to realize the time-related mapping of the spatial correction factor and the synthetic current value, and the synthetic current value corrected at the corresponding moment is calculated by the product of the spatial correction factor and the synthetic current value associated with the corresponding moment.

[0024] In a second aspect, a reactor reactivity measurement system is provided, comprising:

[0025] A current processing module, used for performing weak current-to-voltage conversion and multi-channel filtering processing on the collected detector current signal to obtain multiple first voltage signals;

[0026] A rod position conditioning module is used to condition the collected rod position signal of the rod position to be tested to obtain a rod position conditioning signal;

[0027] The ADC acquisition module is used to perform analog-to-digital conversion on the multiple first voltage signals and the rod position conditioning signals to obtain corresponding digital signals;

[0028] MCU control module, used for:

[0029] Dynamically configure the sampling rate, acquisition conditioning conversion gear and multiple weighting coefficients according to the measurement range and measurement method of the multiple first voltage signals represented by digital signals;

[0030] Converting the multiple first voltage signals into multiple first current signals, and fusing the multiple weighting coefficients with the multiple first current signals to obtain a synthesized current value;

[0031] The synthetic current value is processed in time synchronization according to the rod position conditioning signal to obtain a corrected synthetic current value, and the reactivity measurement and analysis is realized based on the corrected synthetic current value.

[0032] Furthermore, the system also includes:

[0033] The sampling rate configuration module is used to adjust the current working sampling rate setting of the ADC acquisition module in real time according to the configured sampling rate.

[0034] Furthermore, the system also includes:

[0035] The feedback drive module is used to adjust the current working sampling rate setting of the ADC acquisition module in real time according to the configured sampling rate.

[0036] Furthermore, the current processing module includes:

[0037] A current-to-voltage unit is used to perform I / V conversion on the detector current signal to obtain a voltage signal;

[0038] The filtering unit is used to filter the voltage signal through three parallel processing channels with different filtering frequency configurations to obtain

[0039] The first level conversion unit is used to reduce or amplify the voltage signal after filtering to within the voltage sampling range set in the ADC acquisition module.

[0040] Furthermore, the rod position adjustment module includes:

[0041] A signal conditioning unit, used for conditioning the rod position signal of the rod position to be measured;

[0042] The second level conversion unit is used to reduce or amplify the conditioned rod position signal to within the voltage sampling range set in the ADC acquisition module.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] 1. A reactor reactivity measurement method provided by the present invention adopts full digital signal conditioning and synchronous acquisition of detector signal current and rod position signal to be measured to improve the accuracy of parameter correction model, and adopts multi-filter path conditioning and weighted correction to obtain correction data of matching data measurement method; in addition, dynamic loading of configuration parameters is adopted to realize micro-current signal conditioning, acquisition, and initialization of correction parameters.

[0045] 2. The present invention can be applied to occasions requiring high-efficiency experimental measurement of reactivity based on multi-parameter correction and dynamic configuration, rapid expansion of adaptive networking, synchronous signal acquisition and correction, high precision, and online real-time analysis, and can make up for the poor time characteristics of the existing reactivity instrument under the long coaxial cable and the poor measurement lower limit index of the micro-current conditioning unit (about 10 -10 A~10 -9 A), poor anti-interference ability (signal-to-noise ratio), few channels and cannot be networked, no real-time correction and dynamic parameter configuration functions, non-standard interface size and large and heavy weight, low experimental measurement efficiency, etc.

[0046] 3. The present invention effectively improves the adaptability, efficiency and safety of the instrument's test scenarios and experimental measurement tasks, obtains better signal-to-noise ratio and time response characteristics, measures real-time and comprehensive data, has higher data mining potential, and has higher accuracy of experimental results after correction and analysis, greatly improving the quality of reactive measurement analysis results and data mining value;

[0047] 4. Aiming at the insufficiency of existing reactor digital reactivity instruments and the need for data fusion correction analysis models, the present invention designs a special module for digital reactivity instruments under a standard interface and circuit size template, thereby realizing an extensible distributed architecture and modular design of digital reactivity instruments. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0049] Figure 1 is a flow chart of Embodiment 1 of the present invention;

[0050] Figure 2 This is a schematic diagram of the three-channel filtering fusion principle in Embodiment 1 of the present invention;

[0051] Figure 3 is a schematic diagram of a filter loading model in Embodiment 1 of the present invention;

[0052] Figure 4 is a schematic diagram of the synchronous acquisition of multiple signals in Embodiment 1 of the present invention;

[0053] Figure 5 It is a system block diagram in Example 2 of the present invention. DETAILED DESCRIPTION

[0054] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0055] In the reactor core physical parameter measurement method based on current-type neutron detector, since the measuring instrument works in the middle zone of the reactor startup process, the neutron flux in the core environment is about 10 -6 ~10 -8 n / (cm 2 .s), the detector outputs weak signals that need to be output to a radiation-resistant safe position of the device. The signal transmission process is easily interfered by external environmental signals, and the distributed capacitance causes the signal response characteristics to deteriorate, which brings challenges to quickly and accurately obtain the weak current signal of the measurement detector. In order to adapt to the current high efficiency of zero-power physical test processes, high quality of experimental data results, diversity of test scenarios, and complexity of applicable environments (electromagnetic), and in the presence of objective factors such as the power limit of zero-power physical tests, the radiation limit of the measurement end, the statistical fluctuation of neutron detection, and the real-time transmission of weak signals, the requirements for the high signal-to-noise ratio conditioning performance of the weak current signal of the measuring instrument, the ultra-low measurement lower limit index, and the fast time response characteristics of the detector current during the test are higher.

[0056] Based on the above technical status, in order to improve the existing deficiencies, it is necessary to explore new design routes for reactivity measurement instruments and realize the standardized, small-scale integrated, intelligent module design of instruments based on the portable multifunctional instrument equipment architecture. The present invention combines the technologies of channel full digital synchronous acquisition, real-time result correction, parameter dynamic configuration, sensitive circuit shielding design, etc., based on the local distributed layout architecture of the bus and the local radiation-resistant shielding measures, to realize the update and development of the measurement theory and analysis and calculation model of reactor physics experiments.

[0057] Embodiment 1: A method for measuring reactor reactivity, such as Figure 1 As shown, the following steps are included:

[0058] S1: performing weak current-to-voltage conversion and multi-channel filtering processing on the collected detector current signal to obtain multiple first voltage signals;

[0059] S2: Conditioning the collected rod position signal of the rod position to be measured to obtain a rod position conditioning signal;

[0060] S3: performing analog-to-digital conversion on the multiple first voltage signals and the rod position conditioning signals respectively to obtain corresponding digital signals;

[0061] S4: dynamically configuring a sampling rate, an acquisition conditioning conversion gear, and a plurality of weighting coefficients according to a measurement range and a measurement method of the multiple first voltage signals represented by digital signals;

[0062] S5: converting the multiple first voltage signals into multiple first current signals, and fusing the multiple weighting coefficients with the multiple first current signals to obtain a composite current value;

[0063] S6: The synthetic current value is subjected to time synchronization processing according to the rod position conditioning signal to obtain a corrected synthetic current value, and the reactivity measurement and analysis is performed based on the corrected synthetic current value.

[0064] The process of obtaining the composite current value is specifically as follows: multiplying the weighting coefficient with the first current signal converted from the output corresponding to the corresponding filter channel to obtain the second current value; and summing up the multiple second current values ​​to obtain the composite current value.

[0065] like Figure 2 As shown, the best measurement and analysis method is selected by measuring the target in the reactive measurement. In order to meet the dynamic precise matching of the selected measurement and analysis method, full data scene acquisition is adopted. After the I / V conversion of the microcurrent signal introduced by the detector, it enters three parallel processing channels with different filter frequency configurations for processing, and the three current data are collected synchronously.

[0066] The instrument module determines the optimal filter parameter selection in modes such as small reactivity tracking measurement, temperature coefficient measurement, pressure coefficient measurement, drop rod method measurement, and plug rod method measurement through theoretical analysis and experimental verification. The parameter selection mainly involves the sampling rate setting (associated with the time interval δt in the host computer application software) and the adaptation of weighting coefficients k1, k2, and K3. The sampling rate can be set to the following values: 1000Hz (1ms), 200Hz (5ms), 100Hz (10ms), 50Hz (20ms), 20Hz (50ms), 10Hz (100ms), 5Hz (200ms). The selection of its value mainly depends on the measurement interval of the signal, the current measurement mode, the bandwidth of the networking bus, and the real-time computing power of the host computer software. The weighting coefficients k1, k2, and k3 are selected based on the measurement interval of the signal, the current measurement mode, and the parameter characteristics of the signal coaxial cable from the detector to the conditioning end (length, insulation, distributed capacitance, low noise characteristics, etc.).

[0067] For example, the weighting coefficient value model is mainly determined by the gear characteristics of the collected current value, and its specific model is as follows:

[0068] k1=(|-4-d|) / 15 ①

[0069] k2=(|-9-d|) / 15 ②

[0070] k3=(|-13-d|) / 15 ③

[0071] Among them, d in the above formula is the gear value of the current circuit. The gear value is dynamically acquired during the measurement process, and the value can be -13, -12, -11, -10, -9, -8, -7, -6, -5, -4. According to the above model, it can automatically switch and adapt during the measurement process.

[0072] In addition, empirical values ​​can also be obtained based on actual scene conditions. The specific parameter selection table is shown in Table 1.

[0073] Table 1 Parameter selection correspondence table

[0074]

[0075]

[0076] According to the actual scene demand factors, the parameter selection table is adapted to determine the corresponding relationship between the data sampling rate, the weighted coefficients in the three-way weighted fitting model and the optimal filtering parameters, so as to realize the flexible and dynamic configuration requirements in the data collection and analysis process, the data is accurately measured, and the filtering loading model is as follows: Figure 3 shown.

[0077] The dynamic weighted filter loading model is a model that combines hardware filtering with software algorithm optimization. Based on this model, it can be built into the measurement and analysis software. According to the judgment threshold condition parameters, the appropriate configuration parameters are automatically loaded and issued, so that the measurement module circuit can be quickly adapted to meet the current measurement mode and detection measurement signal range. The above process greatly enhances the efficient performance of dynamic parameter adjustment of the instrument module during operation, enhances the adaptability of the instrument test and measurement process, measurement expansion performance, and accuracy under refined measurement.

[0078] In addition, the present invention also adjusts the actual sampling rate of the multiple first voltage signals and the rod position conditioning signals during analog-to-digital conversion in real time according to the configured sampling rate.

[0079] In addition, the present invention also adjusts the current working sampling rate setting of the analog-to-digital conversion in real time according to the configured sampling rate.

[0080] The specific process of obtaining the corrected synthetic current value is as follows: according to the initial sampling time of the rod position conditioning signal and the rod position interval value, the spatial correction factor at the corresponding moment is matched to obtain the spatial correction factor sequence; each sampling rod position is used as a link to realize the time association mapping between the spatial correction factor and the synthetic current value, and the product of the spatial correction factor and the synthetic current value associated with the corresponding moment is calculated to obtain the corrected synthetic current value at the corresponding moment.

[0081] The accuracy of the data correction model is improved by synchronously collecting multiple signals. Specifically, the rod position and the detector current that calculates the current rod position reactivity are synchronously collected to solve the problem of previous design or data processing that did not consider data synchronization or did not estimate and correct data synchronization, which caused the introduction and transmission of errors and was not conducive to the accuracy of data analysis and processing. When making corrections, it is also necessary to experimentally explore the response time of the reactor reactivity changes caused by the rod position changes, such as Figure 4 shown.

[0082] The three-way current is collected synchronously with the rod position, and each sampling value is aligned with the time moment as the reference. Figure 4 The process ① realizes each sampling time t n The corresponding three-way filter current value i n and stick value b n The three-way filtered current values ​​are combined into a current value I at the corresponding moment through the weighted coefficient. n ; Process ② Load the initial spatial correction factor Y based on the rod position through the software n , combined with the synchronously collected rod position interval value △b, the initial spatial factor is adapted (by interpolation expansion or point compression, etc.), and the adaptable spatial correction factor y that can be matched with the current rod position sampling interval is obtained. n ; Process ③ uses each sampling rod site as a link to find the corresponding time and space correction factor, and maps it to the corresponding current value I through time associationn , to realize the spatial factor y of the current at each rod position sampling point in the rod drop measurement mode and rod insertion measurement mode n *Synthetic current value I n correction; process ④ is to carry out dynamic tracking and correction of the whole process in real time measurement according to the reactive inverse dynamic equation to obtain more accurate measurement and analysis results.

[0083] It should be noted that the three-way filtered current value requires converting the voltage signal synchronously collected by AD into a current signal according to the resistance value in the measurement gear, and then analyzing it based on the current information.

[0084] Embodiment 2: A reactor reactivity measurement system, such as Figure 5 As shown, it includes a current processing module, a rod position conditioning module, an ADC acquisition module, an MCU control module, a sampling rate configuration module and a feedback drive module.

[0085] Among them, the current processing module is used to perform weak current conversion to voltage and multi-channel filtering processing on the collected detector current signal to obtain multiple first voltage signals.

[0086] The rod position conditioning module is used to condition the collected rod position signal of the rod position to be tested to obtain a rod position conditioning signal.

[0087] The ADC acquisition module is used to perform analog-to-digital conversion on the multiple first voltage signals and the rod position conditioning signals to obtain corresponding digital signals.

[0088] The MCU control module is used to: dynamically configure the sampling rate, acquisition conditioning conversion gear and multiple weighting coefficients according to the measurement range and measurement method of multiple first voltage signals represented by digital signals; convert the multiple first voltage signals into multiple first current signals accordingly, and fuse the multiple weighting coefficients and the multiple first current signals to obtain a synthetic current value; obtain a corrected synthetic current value after time synchronization processing of the synthetic current value according to the rod position conditioning signal, and realize reactive measurement and analysis based on the corrected synthetic current value.

[0089] The sampling rate configuration module is used to adjust the current working sampling rate setting of the ADC acquisition module in real time according to the configured sampling rate.

[0090] The feedback drive module is used to adjust the current working sampling rate setting of the ADC acquisition module in real time according to the configured sampling rate.

[0091] The present invention adopts network or bus communication function, online parameter configuration and data transmission to realize distributed cascade connection. Micro current 10 is realized inside the unit -4 ~10 -13A conditioning, automatic gear switching, output of fully digital micro-current signal, sampling rate 5Hz, 10Hz, 20Hz (50ms), 50Hz (20ms), 100Hz, 200Hz, 1KHz100Hz (10ms), 10Hz (100ms), can be set, support manual and automatic range switching, automatic range switching output data has no obvious fluctuation. Digital communication transmission signal contains configuration parameter information (sampling rate, filtering parameters, gear connection processing mode, etc.), high voltage state detection information, high voltage load current information stick position measurement value, micro-current measurement value, gear information, etc. The ionization chamber is loaded with positive and negative high voltages. Under the action of the electric field, the radioactivity of the nuclear reaction is ionized in the induction area to produce positive and negative charged particles moving in opposite directions, thereby forming a current.

[0092] The current processing module includes a current-to-voltage unit, a filtering unit, and a first level conversion unit. The current-to-voltage unit is used to perform I / V conversion on the detector current signal to obtain a voltage signal; the filtering unit is used to filter the voltage signal through three parallel processing channels with different filtering frequency configurations to obtain a first level conversion unit, which is used to reduce or amplify the filtered voltage signal to the voltage sampling range set in the ADC acquisition module.

[0093] The rod position conditioning module includes a signal conditioning unit and a second level conversion unit. The signal conditioning unit is used to condition the rod position signal of the rod position to be tested; the second level conversion unit is used to reduce or amplify the conditioned rod position signal to the voltage sampling range set in the ADC acquisition module.

[0094] Micro-current signal conditioning mainly implements signal conversion through transimpedance conversion circuit to complete primary amplification of weak current signals. The amplified signal belongs to the ultra-micro current range, and classic protection technology is required for leakage prevention and anti-interference processing. Then, high-precision ADC is used for acquisition to meet the digital requirements of the site.

[0095] like Figure 5 As shown, the microcurrent interface allows the neutron detector to detect the weak current (10 -4 A~10 -13 A) is introduced into the dedicated module for measuring the reactivity instrument. The present invention adopts the BNC connector of the triaxial Q9, and is designed according to the middle core layer as signal +, the outermost layer as signal -, and the middle layer as the Guard layer; the measurement of the weak current signal is achieved through a resistor feedback network to achieve wide range conversion measurement, and the basic principle of conversion is V o =I in *R 反馈The resistor feedback network uses special resistors with high precision and low temperature drift, and its resistance values ​​are composed of 100G, 1G, 10M, 100K, and 10K resistors; after the voltage is collected, it passes through a combined filtering module based on a weighted coefficient to improve the measurement accuracy and signal-to-noise ratio in the low measurement range during the signal transmission conditioning process, and ensure the rapid response characteristics of the signal in the appropriate measurement range.

[0096] The function of level conversion is to reduce or amplify the signal sent from the front end to the voltage sampling range set by the back-end ADC to avoid burning the ADC chip; the function of ADC acquisition is to convert the front-end analog signal into a digital signal that can be processed by the subsequent digital communication and software of the instrument. The ADC has 4 acquisition channels, which respectively collect three weak current conversion signals and one rod position conditioning signal; the power interface provides the required low-voltage DC power supply for the reactive measurement module; the signal also passes through the buffer output module and the output interface module to provide an analog signal debugging interface to realize the debugging test, inspection and maintenance functions of the reactive measurement module, among which the buffer output module is used to isolate the main link of the signal to avoid external influence on the measurement of the measurement channel; the MCU control module determines the current feedback resistance gear to be selected through the ADC sampling value, and realizes the selection of the feedback resistor in the feedback resistor network through the range switching drive circuit, and at the same time divides the current acquisition voltage value by the current feedback resistance value to obtain the corresponding current value preprocessing, and finally the RJ45 interface, RS485 interface, or CAN bus interface sends the current value to the reactive host computer or multi-functional measurement system to realize the real-time measurement of the reactive.

[0097] In addition, the input interface of the present invention adopts a weak signal dedicated interface with double-layer shielding protection technology to ensure that the leakage current is less than 100fA. The inner shield needs to be protected by equipotential protection technology, and the outer shield adopts ground (casing) shielding to reduce electromagnetic interference. The input protection mainly protects against electrostatic damage, using standard ESD diodes for clamping protection, and cooperating with overcurrent 50mA self-recovery protection fuse to implement overcurrent protection to prevent the internal amplification circuit from being damaged by external signals.

[0098] The primary amplification of weak current adopts the classic weak current amplification mode. The resistance feedback network is composed of resistors and capacitors. The feedback network is switched according to the MCU command to achieve multi-level controllable range. The range switching adopts ultra-low leakage current type relay, whose leakage resistance is as low as 1T and the response time is within the ms level, which can meet the safety, speed and reliability of range switching. The primary op amp adopts ADI's electrometer JFET output amplifier to ensure the error level of fA level. The resistance feedback network adopts ultra-high performance resistors and capacitors in parallel. The resistors adopt multiple levels of 100G--10K, and their temperature drift is 50ppm / ℃@100G; when switching resistors, it is necessary to pay attention to the intersection time between the two ranges to prevent the op amp from opening the loop and make the output reach the power rail; the capacitor adopts RS ultra-low leakage current type polypropylene film capacitor, with a leakage resistance of not less than 1T, and a good meson absorption rate to meet the design requirements.

[0099] The filter circuit adopts 4th-order Butterworth active filter to eliminate input interference, and its cut-off frequency is 1KHz. The output buffer adopts capacitor drive circuit to ensure the integrity of the signal after driving the cable and reduce the adverse factors caused by the cable capacitance.

[0100] The control processor uses the STM32F4 core processor to realize a series of functional requirements such as command parsing, GPIO control, ADC acquisition and processing of the preamplifier. In order to meet the digital requirements, a high-precision ADC is designed inside the preamplifier, allowing 1KHz high-speed and high-precision conversion of the signal. At the same time, the communication is mainly equipped with network communication, and the protocol conversion is realized through mature network chips.

[0101] In order to enhance the adaptability of the instrument, it is necessary to have a fast dynamic adaptation technology as support. In multi-scenario and multi-method applications, it is even more necessary to assist with flexible and accurate dynamic configuration strategies. At the beginning of the module operation, the configuration parameters sent by the instrument host are accepted for loading, and the predetermined measurement mode and weighting coefficients are entered. During the whole process of the instrument measurement operation, the corresponding parameter changes are dynamically adapted to the changes in the measurement content to perform uninterrupted experimental measurement tasks. According to application requirements (number of measurement channels, measurement purpose, etc.) and resources (bus transmission bandwidth limitations, etc.), the interface and data structure for external data transmission can be reasonably selected to control the data transmission volume, etc.

[0102] The range switching adopts the GPIO drive mode. The software changes the gain gear through instructions and can set the automatic range. When the result collected by ADC meets the range switching threshold, the software automatically implements the range switching.

[0103] Working principle: The present invention adopts full digital signal conditioning and synchronous acquisition of the detector signal current and the rod position signal to be measured to improve the accuracy of the parameter correction model. At the same time, it adopts multi-filter path conditioning and weighted correction to obtain corrected data for the matching data measurement method. In addition, dynamic loading of configuration parameters is adopted to realize micro-current signal conditioning, acquisition, and initialization of correction parameters.

[0104] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0105] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0106] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0107] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0108] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method 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 in the scope of protection of the present invention.

Claims

1. A method for measuring reactor reactivity, characterized in that: The following steps are involved: Performing weak current-to-voltage conversion and multi-channel filtering processing on the collected detector current signal to obtain multiple first voltage signals; Conditioning the collected rod position signal of the rod position to be measured to obtain a rod position conditioning signal; Performing analog-to-digital conversion on the multiple first voltage signals and the rod position conditioning signals respectively to obtain corresponding digital signals; Dynamically configure the sampling rate, acquisition conditioning conversion gear and multiple weighting coefficients according to the measurement range and measurement method of the multiple first voltage signals represented by digital signals; Converting the multiple first voltage signals into multiple first current signals, and fusing the multiple weighting coefficients with the multiple first current signals to obtain a synthesized current value; The synthetic current value is processed in time synchronization according to the rod position conditioning signal to obtain a corrected synthetic current value, and the reactivity measurement and analysis is realized based on the corrected synthetic current value.

2. A method for measuring reactor reactivity according to claim 1, characterized in that: The method further includes: The actual sampling rate of the multiple first voltage signals and the rod position conditioning signals during analog-to-digital conversion is adjusted in real time according to the configured sampling rate.

3. A method for measuring reactor reactivity according to claim 1, characterized in that: The method further includes: The current operating sample rate setting for the analog-to-digital conversion is adjusted in real time according to the configured sample rate.

4. A method for measuring reactor reactivity according to claim 1, characterized in that: The process of obtaining the synthetic current value is specifically as follows: Multiplying the weighting coefficient with the first current signal converted from the output corresponding to the corresponding filter channel to obtain a second current value; The multiple second current values ​​are summed to obtain a composite current value.

5. A method for measuring reactor reactivity according to claim 1, characterized in that: The process of obtaining the modified synthetic current value is specifically as follows: According to the initial sampling time of the rod position conditioning signal and the rod position interval value, the spatial correction factor at the corresponding moment is matched to obtain a sequence of spatial correction factors; Each sampling rod site is used as a link to realize the time-related mapping of the spatial correction factor and the synthetic current value, and the synthetic current value corrected at the corresponding moment is calculated by the product of the spatial correction factor and the synthetic current value associated with the corresponding moment.

6. A reactor reactivity measurement system, characterized in that: include: A current processing module, used for performing weak current-to-voltage conversion and multi-channel filtering processing on the collected detector current signal to obtain multiple first voltage signals; A rod position conditioning module is used to condition the collected rod position signal of the rod position to be tested to obtain a rod position conditioning signal; The ADC acquisition module is used to perform analog-to-digital conversion on the multiple first voltage signals and the rod position conditioning signals to obtain corresponding digital signals; MCU control module, used for: Dynamically configure the sampling rate, acquisition conditioning conversion gear and multiple weighting coefficients according to the measurement range and measurement method of the multiple first voltage signals represented by digital signals; Converting the multiple first voltage signals into multiple first current signals, and fusing the multiple weighting coefficients with the multiple first current signals to obtain a synthesized current value; The synthetic current value is processed in time synchronization according to the rod position conditioning signal to obtain a corrected synthetic current value, and the reactivity measurement and analysis is realized based on the corrected synthetic current value.

7. A reactor reactivity measurement system according to claim 1, characterized in that: The system also includes: The sampling rate configuration module is used to adjust the current working sampling rate setting of the ADC acquisition module in real time according to the configured sampling rate.

8. A reactor reactivity measurement system according to claim 1, characterized in that: The system also includes: The feedback drive module is used to adjust the current working sampling rate setting of the ADC acquisition module in real time according to the configured sampling rate.

9. A reactor reactivity measurement system according to claim 1, characterized in that: The current processing module comprises: A current-to-voltage unit is used to perform I / V conversion on the detector current signal to obtain a voltage signal; The filtering unit is used to filter the voltage signal through three parallel processing channels with different filtering frequency configurations to obtain The first level conversion unit is used to reduce or amplify the voltage signal after filtering to within the voltage sampling range set in the ADC acquisition module.

10. A reactor reactivity measurement system according to claim 1, characterized in that: The rod position conditioning module comprises: A signal conditioning unit, used for conditioning the rod position signal of the rod position to be measured; The second level conversion unit is used to reduce or amplify the conditioned rod position signal to within the voltage sampling range set in the ADC acquisition module.

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