On-line measurement multi-instrument centralized control integration technology for in-reactor irradiation test

Abstract

The invention relates to the field of irradiation technology, in particular to an in-pile irradiation test on-line measurement multi-instrument centralized control integration technology which comprises a primary instrument assembly, an on-line measurement instrument coupling design, a signal processing unit integration system and a master control room upper computer in communication connection with the signal processing unit integration system. The primary instrument assembly comprises an SPND, a sheathed thermocouple, an optical fiber sensor, an LVDT and other current type sensors; the on-line measuring instrument coupling design is used for realizing physical connection and signal leading-out of the primary instrument assembly, the irradiation device and the reactor pressure boundary; the signal processing unit integrated system is used for receiving a voltage signal, a current signal or an optical signal output by the primary instrument assembly, and remotely transmitting the voltage signal, the current signal or the optical signal to a master control room upper computer after acquisition, amplification, noise reduction, filtering and analog-to-digital conversion; a primary instrument signal is directly accessed to the irradiation device through coupling design, and a signal cable is directly connected with the integrated system cabinet acquisition module. According to the invention, the effect of one-stop access of the primary instrument is realized.

Description

Technical Field

[0001] This application relates to the field of irradiation technology, and in particular to an integrated technology for centralized control of multiple instruments for online measurement in in-pile irradiation tests. Background Technology

[0002] In the field of online measurement of reactor irradiation deformation, major international nuclear powers began related research in the 1960s, while China still lags behind in key sensor technologies and system integration. Specifically, this manifests in insufficient independent R&D capabilities for linear variable differential transformers (LVDTs), with the design level of their off-pile test verification devices and on-pile radiation tolerance testing platforms lagging behind international standards. Self-powered neutron detectors (SPNDs) have long relied on imports, and the process of domestic substitution urgently needs to be accelerated to enhance the nuclear industry's independent innovation capabilities and strategic security level. Furthermore, although radiation-resistant optical fibers have achieved market application, their current radiation dose threshold is still lower than the actual irradiation intensity of the on-pile test channels, requiring breakthroughs in material performance bottlenecks and multiple rounds of on-pile verification tests before engineering applications can be realized.

[0003] While domestic research institutions have continuously invested in the research and development of electronics and online measurement instrumentation technologies, and various units have achieved phased results in the fields of LVDT, SPND, and radiation-resistant optical fibers through university-industry cooperation, including completing multiple batches of in-reactor verification tests and realizing product transformation, systemic challenges still exist. Currently, various sensors (such as LVDT, SPND, and radiation-resistant optical fibers) and their supporting capacitive and pressure sensors are all independently developed, resulting in each instrument having its own dedicated data acquisition unit, processing module, and human-machine interface. This distributed architecture requires additional integration of heterogeneous systems when multiple instruments are used collaboratively in the same reactor irradiation test, increasing hardware costs and development time, and reducing measurement reliability due to differences in interface protocols and asynchronous data.

[0004] The core of the current technological bottleneck lies in the lack of a unified system integration solution. When multiple online measuring instruments are deployed in the same irradiation environment, the data acquisition, processing, and display configuration interfaces of each independent system are incompatible, forcing technicians to repeatedly configure multiple software platforms on the host computer in the main control room. This not only causes operational redundancy and resource waste, but also makes it difficult to achieve multi-parameter correlation analysis and real-time collaborative monitoring due to inconsistent data formats, severely restricting the efficiency and safety of comprehensive evaluation of in-core irradiation performance parameters. Summary of the Invention

[0005] To achieve one-stop access for primary instruments, this application provides a centralized control integration technology for multiple instruments used in online measurement of in-pile irradiation tests.

[0006] This application provides a multi-instrument centralized control integration technology for online measurement of in-pile irradiation tests, which adopts the following technical solution: A multi-instrument centralized control integration technology for online measurement in-pile irradiation tests includes: A primary instrumentation assembly, installed in the irradiation device within the reactor, is used for online sensing of irradiation performance parameters. The primary instrumentation assembly includes SPND, armored thermocouples, fiber optic sensors, LVDT, and other current-type sensors. Online measuring instruments, wherein the online measuring instruments are coupled in a design that enables the physical connection and signal extraction between the primary instrument components and the irradiation device and the reactor pressure boundary; The signal processing unit integrated system is used to receive voltage signals, current signals or optical signals output by primary instrument components, and transmit them to the host computer in the main control room after acquisition, amplification, noise reduction, filtering and analog-to-digital conversion. The host computer in the main control room is connected to the integrated system of the signal processing unit. The host computer in the main control room is used to receive and display the processed irradiation performance parameter data and can plot the parameter change curves. Among them, the primary instrument signal is directly connected to the irradiation device through a coupling design, and the signal cable is directly connected to the acquisition module of the integrated system cabinet; the signal processing unit integrated system adopts a one-in-one-backup redundant design.

[0007] By adopting the above technical solutions, the primary instrumentation component integrates SPND, armored thermocouples, fiber optic sensors, LVDT, and other current-type sensors to achieve synchronous online sensing of multi-dimensional performance parameters such as neutron flux, temperature, pressure, and specimen deformation during irradiation tests. The online measurement instrument coupling design simplifies the complex process of distributed installation, reduces signal relay links, and lowers electromagnetic interference and transmission loss. At the same time, it ensures reliable sealed connections between the in-pile probe and the device, as well as pressure boundaries, guaranteeing the stability of signal extraction under extreme environments. The signal processing unit integrated system can seamlessly switch to the backup module when one module fails, improving the continuity and safety of system operation. Furthermore, by integrating functions such as acquisition, amplification, noise reduction, filtering, and analog-to-digital conversion, it avoids compatibility issues of scattered equipment and optimizes signal processing accuracy and efficiency. The host computer in the main control room communicates with the integrated system, which can not only display multi-parameter data and plot change curves in real time, realizing full-process visual monitoring of the irradiation test, but also provide support for subsequent data analysis and algorithm iteration through data storage and recording functions.

[0008] Preferably, the probe portion of each sensor in the primary instrumentation assembly is armored and integrated with the armored cable. The end of the armored cable passes through a sealed interface designed for coupling with the online measuring instrument and exits the irradiation device or the reactor. The sealed interface includes a metal sealing flange and insulating sealing filler. The sealed interface is used to realize in-pile installation and signal extraction. The connection method between each sensor probe and the armored cable is welding or integrated pull-out.

[0009] By adopting the above technical solution, each sensor probe is integrated with the armored cable after being armored. Utilizing the high temperature resistance, high pressure resistance, and radiation resistance of the armor material, the mechanical strength of the probe is improved in the strong radiation, high temperature, and high pressure environment inside the reactor, avoiding measurement failure due to probe deformation, corrosion, or radiation damage, and extending the service life of the primary instrument. The end of the armored cable passes through a sealed interface containing a metal sealing flange and insulating sealing filler to exit the irradiation device or reactor. The metal sealing flange achieves physical sealing of the internal pressure boundary through rigid fastening, preventing leakage of radioactive media. The insulating sealing filler fills the interface gap to isolate electrical interference and ensure electrical isolation between the probe and the external environment. The probe and armored cable are connected by welding or integrated pull-out connection, eliminating the risk of loosening under long-term vibration and thermal cycling of traditional detachable connections, forming a continuous and stable conductive path, and avoiding signal attenuation or interruption due to poor contact.

[0010] Preferably, the SPND includes a rhodium wire collector, an Al2O3 insulator, and an Inconel emitter; the Inconel emitter is nested inside the rhodium wire collector, the Inconel emitter is welded to the transmission cable, and electrical isolation between the Inconel emitter and the rhodium wire collector is achieved by filling with the Al2O3 insulator; the Inconel emitter, the rhodium wire collector, and the Al2O3 insulator together form a cylindrical probe, which is welded to an armored signal cable and then pulled out to form an integrated in-pile primary instrument. This probe is connected to an online measuring instrument via an armored cable coupling design.

[0011] By adopting the above technical solution, the emitter is nested inside the rhodium wire collector, and the two are electrically isolated by filling with Al2O3 insulator. This avoids the risk of short circuit between the emitter and the collector, and enhances the sensitivity of neutron fluence sensing through the collection and enhancement effect of the collector on the emitted radiation signal. At the same time, the high-temperature stability and insulation of Al2O3 material ensure consistent electrical performance under long-term irradiation. The emitter and transmission cable are welded together, and the probe and armored signal cable are welded together and then pulled out to form an integrated structure. This eliminates the risk of loosening under vibration and thermal cycling in traditional detachable connections, forming a continuous, low-impedance conductive path and reducing attenuation and interference in signal transmission. The cylindrical probe shape is adapted to the installation layout of the narrow space in the reactor, and the integrated pulling process with the armored cable enhances the overall mechanical strength of the probe and resists material embrittlement or deformation caused by irradiation. The alloy material combination of the Inconel emitter and the rhodium wire collector has excellent radiation resistance and can work stably for a long time in the strong neutron field in the reactor, avoiding measurement deviations caused by material activation or performance degradation.

[0012] Preferably, the armored thermocouple includes a K-type armored thermocouple, an armored cable, a compensating wire, and a temperature acquisition module; the K-type armored thermocouple has an outer diameter of 1mm and is resistant to high temperature of 1000℃, high pressure, and water / air media; the K-type armored thermocouple is connected to the compensating wire through the armored cable, the other end of the compensating wire is connected to the signal input terminal of the temperature acquisition module, and the signal output terminal of the temperature acquisition module is connected to the signal processing unit integrated system through a network cable.

[0013] By adopting the above technical solutions, the K-type armored thermocouple features a miniaturized design with an outer diameter of 1mm, adapting to the installation layout in the confined space within the reactor core and avoiding interference with the irradiation flow field or the test specimen. It also possesses adaptability to composite environments with temperatures up to 1000℃, high pressure, and water / air media, enabling long-term stable operation in extreme temperature and pressure fluctuations and complex media within the reactor core, preventing measurement failure due to material oxidation, deformation, or performance degradation. The armored cable, serving as the connection carrier between the thermocouple and the compensating wire, combines mechanical protection and signal shielding functions, resisting in-core vibration, irradiation damage, and electromagnetic interference, ensuring the continuity of temperature signal transmission. The introduction of the compensating wire specifically corrects the cold junction temperature drift error of the thermocouple, and combined with the preliminary conditioning of the analog signal by the temperature acquisition module, improves the accuracy of the raw temperature data. The temperature acquisition module is connected to the signal processing unit integrated system via a network cable, achieving long-distance, low-loss transmission of digital signals, avoiding attenuation and crosstalk in traditional analog signal transmission, laying the foundation for subsequent integrated processing.

[0014] Preferably, the fiber optic sensor includes a grating assembly, an optical cable assembly, and a fiber optic sensor demodulator; the grating assembly contains 12 sensors, which are connected to 12 MT multi-path converters through 12 FC / APC connectors of the optical cable assembly, wherein each sensor integrates a strain sensor and a temperature sensor to measure the strain value or temperature value at a single point. The optical cable assembly includes a 100m optical fiber patch cord. One end of the optical cable assembly is connected to the grating assembly via an MT multi-path converter, and the other end of the optical cable assembly is connected to the 12 demodulation channels of the optical fiber sensor demodulator. The output end of the optical fiber sensor demodulator is connected to the signal processing unit integrated system via a signal cable. The grating or enamel cavity of the optical fiber sensor probe is fused with the optical fiber pigtail and then armored through an Inconel stainless steel thin tube, passing through a protective tube and a sealing flange before exiting the irradiation device and reactor.

[0015] By adopting the above technical solution, the grating assembly integrates 12 sensors, which are connected to 12 MT multi-path converters via 12 FC / APC connectors, forming a one-to-one correspondence architecture of 12 sensors and 12 channels. This achieves simultaneous sensing of multi-point deformation and temperature of the test specimen, improving monitoring density and data correlation. Furthermore, the centralized management of the multi-path converters avoids signal crosstalk, ensuring the independence of single-point measurements. The optical cable assembly includes a 100m fiber optic patch cord, the length of which is adapted to the spacing layout of the in-pile irradiation device and signal processing unit. The flexible optical fiber material also possesses anti-electromagnetic interference properties, ensuring long-distance transmission of optical signals. To ensure stability, the fiber optic sensor demodulator is equipped with 12 demodulation channels that precisely match 12 sensors. It converts the light signals reflected by the grating / epper cavity into electrical signals. The output end is connected to the signal processing unit integrated system through a signal cable to realize subsequent processing of digital signals. After the grating or epper cavity of the probe is fused with the fiber optic pigtail, it is armored through an Inconel stainless steel tube, and then passes through a protective tube and a sealing flange to exit the irradiation device and reactor. The armor structure resists mechanical vibration and irradiation damage inside the reactor, and the sealing flange achieves physical isolation of the pressure boundary and safe signal extraction. The fusion connection eliminates the risk of optical loss of the detachable interface.

[0016] Preferably, the fiber optic sensor demodulator includes a demodulation module and a central processing unit; wherein, the demodulation module includes a beam splitter, a coupler, a wavelength-tunable light source module, a photodetector, an analog signal amplification circuit, an AD conversion circuit, and an FPGA demodulation module, and all components are connected in series via an internal bus; the central processing unit includes a power supply module, a processing circuit, a storage circuit, a bus interface, and a conversion circuit, and is connected to the demodulation module via the bus interface; the demodulated electrical signal is processed by the central processing unit and then output to the signal processing unit integrated system via a signal cable.

[0017] By adopting the above technical solution, the demodulation module connects the beam splitter, coupler, wavelength-tunable light source module, photodetector, analog signal amplification circuit, AD conversion circuit, and FPGA demodulation module in series via an internal bus, forming a coherent processing link of optical signal splitting - light source excitation - photoelectric conversion - amplification - digitization - high-speed demodulation. The internal bus centrally transmits control signals and data, reducing interference and signal attenuation from discrete multi-node connections, and improving the efficiency and stability of optical signal demodulation. The FPGA demodulation module, with its parallel computing capabilities, achieves high-frequency resolution of the wavelength of light reflected from the grating / enamel cavity, meeting the requirements of in-pile processing. To meet the real-time monitoring requirements of dynamic parameters during irradiation testing, the wavelength-tunable light source module ensures the stability of the light source and reduces ambient light interference through precise tuning. The central processing unit integrates the power supply module, processing circuit, storage circuit, bus interface, and conversion circuit. It connects to the demodulation module through the bus interface, enabling both monitoring and parameter configuration of the demodulation process. It also performs noise reduction and normalization on the demodulated electrical signal to avoid glitches or drift in the original signal affecting subsequent processing. Finally, the processed electrical signal is output to the signal processing unit integrated system via signal cables, forming a complete optical-electrical-digital conversion closed loop.

[0018] Preferably, the other current-type sensor includes a current-type sensor probe, a multi-channel low-current amplifier, an ADC, and a microcontroller integrated circuit; the probe is connected to the input terminal of the multi-channel low-current amplifier via an armored cable, the output terminal of the amplifier is connected to the input terminal of the ADC, the output terminal of the ADC is connected to the input terminal of the microcontroller integrated circuit, and the output terminal of the microcontroller integrated circuit is connected to the signal processing unit integrated system via a network cable.

[0019] By adopting the above technical solution, the current-type sensor probe is connected to a multi-channel low-current amplifier via an armored cable. The high-temperature resistance, radiation resistance, and mechanical protection of the armored cable protect the probe from damage caused by strong radiation, high temperature and pressure, and vibration in the reactor core. It also shields against external electromagnetic interference, ensuring the pure extraction of weak current signals. The multi-channel low-current amplifier precisely amplifies the weak current signal output by the probe, increasing the signal amplitude to the range that the ADC can effectively sample, reducing the drowning effect of environmental noise on weak signals. Furthermore, the multi-channel design supports the simultaneous connection of multiple similar sensors, adapting to the needs of parallel monitoring of multiple parameters. The amplified analog signal is converted into a digital quantity by the ADC, achieving precise quantification of the current and laying the foundation for subsequent digital processing. The microcontroller integrated circuit performs preliminary processing of the digital signal. The integrated design reduces compatibility issues of discrete components and improves processing efficiency. The microcontroller output transmits the processed digital signal to the signal processing unit integrated system via a network cable. The anti-interference capability and long-distance transmission stability of the network cable prevent signal attenuation, ensuring complete data access to the back-end system.

[0020] Preferably, the LVDT includes a primary coil, a secondary coil, an iron core, a coil frame, a shell, a microcontroller integrated circuit, and a DC-to-AC module, wherein there are at least two secondary coils; the primary coil is connected to the output terminal of the DC-to-AC module, and the input terminal of the DC-to-AC module is connected to a power supply; the iron core is mechanically connected to the test piece and moves within the coil frame as the test piece deforms; the output terminals of the two secondary coils are connected to the input terminals of the microcontroller integrated circuit, which integrates amplification, filtering, and demodulation functions, and its output terminal is connected to the signal processing unit integrated system via an armored cable.

[0021] By adopting the above technical solution, the primary coil is connected to the output of the DC-to-AC module, converting the DC power supply into a high-frequency AC excitation signal input to the primary coil. This avoids the zero-point drift problem under DC excitation and provides a stable energy source for the electromagnetic induction of the core and secondary coil, adapting to the complex power supply environment within the reactor. At least two secondary coils are provided. After the core is mechanically connected to the test piece, it moves within the coil frame with the deformation, changing the magnetic coupling strength of the two secondary coils and generating a differential voltage signal proportional to the displacement. The differential output design effectively cancels common-mode interference, improving the sensitivity and linearity of deformation measurement. The coil frame and shell form a closed protective structure, resisting damage to the coils from in-reactor irradiation, high temperature, and mechanical vibration, ensuring the geometric stability of the core sensing unit. The outputs of the two secondary coils are connected to a microcontroller integrated circuit with integrated amplification, filtering, and demodulation functions. This microcontroller performs pre-amplification, bandpass filtering, and phase-sensitive demodulation on the weak differential signal, ultimately outputting a digital signal proportional to the deformation. The microcontroller output is connected to the signal processing unit integrated system via an armored cable, ensuring that the signal is protected from electromagnetic interference and physical damage during long-distance transmission.

[0022] Preferably, the online measurement instrument coupling design includes a coordinated arrangement structure, a cable fixing structure, and a sealed connection structure; the coordinated arrangement structure is used for the relative positioning of the test specimen with SPND, armored thermocouple, fiber optic sensor, LVDT, and other current-type sensor probes; the cable fixing structure is used for fixing the routing of the armored signal cable within the irradiation device and preventing interference; the sealed connection structure is the transition interface between the armored cable and the outlet of the irradiation device and the pressure boundary of the reactor pressure vessel, including a double-layer metal sealing flange and ceramic insulating filler, to achieve physical isolation and signal conduction between the inside and outside of the reactor.

[0023] By adopting the above technical solutions, the coordinated layout structure precisely positions the test specimen relative to the SPND, armored thermocouples, fiber optic sensors, LVDT, and other current-type sensor probes, avoiding spatial interference and measurement blind spots between multiple probes. This ensures that each sensor is at its optimal sensing point, improving the measurement accuracy of multi-parameter spatial correlation. The cable fixing structure plans and fixes the armored signal cables within the irradiation device, preventing cables from tangling, wearing, or breaking due to in-pile vibration, thermal expansion, or irradiation creep. This ensures the long-term stability of the signal transmission path and reduces signal attenuation or interruption caused by cable displacement. The sealed connection structure uses a transition interface with a double-layer metal sealing flange and ceramic insulating filler. The double-layer metal flange enhances the sealing of the pressure boundary through rigid superposition, preventing leakage of radioactive media. The ceramic insulating filler fills the interface gap, achieving both in-pile and out-of-pile electrical isolation to avoid interference and ensuring low-impedance conduction of the signal cables.

[0024] A method for online measurement of in-pile irradiation performance parameters includes the following steps: S1. Through online measurement instrument coupling design, the primary instrument probes of SPND, armored thermocouple, fiber optic sensor, LVDT, and other current-type sensors are coordinated with the test piece and sealed to the irradiation device and reactor pressure boundary via armored cables to achieve in-pile installation and signal extraction. S2. A redundant acquisition mode with one active and one standby is adopted. The voltage / current / optical signals output by the primary instrument are received by the integrated system through the signal processing unit, and then amplified, denoised, filtered and converted from analog to digital in sequence. S3 integrates nonlinear correction, simulation algorithms, and compensation algorithms to optimize the converted digital signal and obtain neutron flux, temperature, pressure, and deformation parameters; S4. The processed parameters are transmitted to the host computer in the main control room via network cable. The real-time parameters and change curves are displayed on the process flow diagram through configuration software, and the parameters are stored, recorded and anomaly alarms are triggered synchronously. S5 supports multi-parameter correlation analysis, allowing users to switch between displaying single-parameter curves and multi-parameter superimposed trends, providing data support for irradiation effect research.

[0025] By adopting the above technical solutions, S1, through the coordinated arrangement and sealed connection of the online measurement instrument coupling design, accurately positions the multi-sensor probes in the sensitive areas of the test specimen. Signals from inside and outside the stack are safely extracted via armored cables, avoiding spatial interference and sealing leakage risks associated with dispersed installations, thus laying the physical foundation for synchronous monitoring of multiple parameters. S2 employs a redundant acquisition mode with one active and one standby module, seamlessly switching to the standby module in case of a failure in one acquisition module, ensuring the continuity of signal acquisition. Simultaneously, through coherent preprocessing of amplification, noise reduction, filtering, and analog-to-digital conversion, environmental noise and interference in the original signal are eliminated, improving data purity. S3 integrates nonlinear... The calibration, simulation, and compensation algorithms specifically correct sensor nonlinearity errors, environmental temperature drift, and irradiation interference, optimizing the converted digital signals into key parameters such as neutron flux, temperature, pressure, and deformation, thereby improving measurement accuracy and adaptability. S4 transmits data remotely to the host computer in the main control room via network cable, displaying parameters and change curves in real time using configuration software. It also synchronously stores records and triggers abnormal alarms, enabling full-process visual monitoring and risk warning for irradiation experiments, ensuring experimental safety. S5 supports multi-parameter correlation analysis and single / multi-curve switching display, indicating the intrinsic correlation between parameters and providing multi-dimensional data support for research on the effects of material / fuel irradiation swelling and creep.

[0026] In summary, this application includes at least one of the following beneficial technical effects: 1. The primary instrumentation system integrates SPND, armored thermocouples, fiber optic sensors, LVDT, and other current-type sensors to achieve synchronous online sensing of multiple performance parameters such as neutron flux, temperature, pressure, and specimen deformation during irradiation experiments. The online measurement instrument coupling design simplifies the complex process of distributed installation, reduces signal relay links, and lowers electromagnetic interference and transmission loss. At the same time, it ensures reliable sealed connections between the in-pile probe and the device, as well as pressure boundaries, guaranteeing signal extraction stability under extreme environments. The signal processing unit integrated system can seamlessly switch to the backup module when one module fails, improving the continuity and safety of system operation. Furthermore, by integrating functions such as acquisition, amplification, noise reduction, filtering, and analog-to-digital conversion, it avoids compatibility issues of scattered equipment and optimizes signal processing accuracy and efficiency. The host computer in the main control room communicates with the integrated system, which can not only display multi-parameter data and plot change curves in real time, realizing full-process visual monitoring of the irradiation experiment, but also provide support for subsequent data analysis and algorithm iteration through data storage and recording functions.

[0027] 2. The K-type armored thermocouple features a miniaturized design with an outer diameter of 1mm, adaptable to the confined space within the reactor core, avoiding interference with the irradiation flow field or the test specimen. It also possesses adaptability to complex environments including 1000℃ high temperature, high pressure, and water / air media, enabling long-term stable operation in extreme temperature and pressure fluctuations and complex media within the reactor core, preventing measurement failure due to material oxidation, deformation, or performance degradation. The armored cable, serving as the connection carrier between the thermocouple and the compensating wire, combines mechanical protection and signal shielding functions, resisting in-core vibration, irradiation damage, and electromagnetic interference, ensuring the continuity of temperature signal transmission. The introduction of the compensating wire specifically corrects the cold junction temperature drift error of the thermocouple, and combined with the preliminary conditioning of the analog signal by the temperature acquisition module, improves the accuracy of the raw temperature data. The temperature acquisition module is integrated with the signal processing unit system via a network cable, achieving long-distance, low-loss transmission of digital signals, avoiding attenuation and crosstalk in traditional analog signal transmission, laying the foundation for subsequent integrated processing.

[0028] 3. S1, through the coordinated arrangement and sealed connection of online measurement instrument coupling design, precisely positions multiple sensor probes in the sensitive areas of the test specimen. Signals from inside and outside the stack are safely extracted via armored cables, avoiding spatial interference and sealing leakage risks associated with dispersed installations, thus laying the physical foundation for synchronous monitoring of multiple parameters. S2 employs a redundant acquisition mode with one active and one standby module, seamlessly switching to the standby module in case of a failure in one acquisition module, ensuring continuous signal acquisition. Simultaneously, through coherent preprocessing of amplification, noise reduction, filtering, and analog-to-digital conversion, environmental noise and interference in the original signal are eliminated, improving data purity. S3 integrates nonlinear correction and simulation... The algorithm and compensation algorithm specifically correct sensor nonlinearity errors, environmental temperature drift, and irradiation interference, optimizing the converted digital signal into key parameters such as neutron flux, temperature, pressure, and deformation, thereby improving measurement accuracy and adaptability. S4 transmits data remotely to the host computer in the main control room via network cable, displaying parameters and change curves in real time using configuration software, synchronously storing records and triggering abnormal alarms, realizing full-process visual monitoring and risk warning of irradiation experiments, and ensuring experimental safety. S5 supports multi-parameter correlation analysis and single / multi-curve switching display, indicating the intrinsic correlation between parameters, and providing multi-dimensional data support for the study of material / fuel irradiation swelling, creep, and other effects. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the integrated control technology for online measurement of multi-instrument systems in in-pile irradiation tests, as described in this application embodiment. Figure 2 It is a design diagram that reflects the coupling of primary instruments and devices in online measurement multi-system. Detailed Implementation

[0030] The following is in conjunction with the appendix Figure 1-2 This application will be described in further detail.

[0031] This application discloses a multi-instrument centralized control integration technology for online measurement of in-pile irradiation tests. (Refer to...) Figure 1 and Figure 2 The integrated technology for centralized control of multiple instruments for online measurement in in-reactor irradiation tests includes primary instrumentation components, online measurement instruments, a signal processing unit integrated system, and a host computer in the main control room. The primary instrumentation components are installed in the irradiation device within the reactor and are used for online sensing of irradiation performance parameters. These components include SPNDs, armored thermocouples, fiber optic sensors, LVDTs, and other current-type sensors. The online measurement instruments are coupled to achieve physical connection and signal output between the primary instrumentation components and the irradiation device and reactor pressure boundaries. The signal processing unit integrated system receives voltage, current, or optical signals output from the primary instrumentation components, and transmits them to the host computer in the main control room after acquisition, amplification, noise reduction, filtering, and analog-to-digital conversion. The host computer in the main control room is communicatively connected to the signal processing unit integrated system, receiving and displaying the processed irradiation performance parameter data and plotting parameter change curves. In an optional embodiment, the primary instrumentation signals are directly connected to the irradiation device via the coupling design, and the signal cables are directly connected to the acquisition module in the integrated system cabinet. The signal processing unit integrated system employs a one-in-one redundancy design.

[0032] The primary instrumentation unit integrates SPND, armored thermocouples, fiber optic sensors, LVDT, and other current-type sensors to achieve synchronous online sensing of multi-dimensional performance parameters such as neutron flux, temperature, pressure, and specimen deformation during irradiation experiments, providing a comprehensive data foundation for the study of material and fuel irradiation effects. The online measurement instrumentation coupling design simplifies the complex process of distributed installation by directly connecting primary instrument signals to the irradiation device and directly connecting signal cables to the integrated system cabinet acquisition module, reducing signal relay links, lowering electromagnetic interference and transmission loss, while ensuring reliable sealed connections between the in-core probe and the device, as well as pressure boundaries, guaranteeing signal extraction stability under extreme environments.

[0033] The signal processing unit integrated system adopts a redundancy design with one active and one backup module. In the event of a module failure, it can seamlessly switch to the backup module, improving the continuity and safety of system operation. Simultaneously, by integrating functions such as acquisition, amplification, noise reduction, filtering, and analog-to-digital conversion, it avoids compatibility issues of scattered equipment and optimizes signal processing accuracy and efficiency. The host computer in the main control room communicates with the integrated system, enabling real-time display of multi-parameter data and plotting of change curves, achieving full-process visual monitoring of the irradiation test. It also provides support for subsequent data analysis and algorithm iteration through data storage and recording functions. Through the integrated architecture of sensor-coupling-processing-monitoring, it solves the problems of traditional online measurement systems, such as fragmented configuration, large space occupation, low signal reliability, and high maintenance costs, building an efficient platform for accurate, stable, and multi-dimensional online measurement of in-pile irradiation performance parameters.

[0034] In the primary instrumentation assembly, the probes of each sensor are armored and integrated with armored cables. The ends of the armored cables pass through sealed interfaces designed for coupling with online measurement instruments, exiting the irradiation device or the reactor. These sealed interfaces include metal sealing flanges and insulating sealing fillers, enabling in-reactor installation and signal extraction. The connection between each sensor probe and the armored cable is either welded or integrally pulled. Each sensor probe is armored (e.g., with a thin stainless steel tube) and integrated with the armored cable. Utilizing the high-temperature resistance, high-pressure resistance, and radiation resistance of the armor material, the mechanical strength and environmental adaptability of the probes in the strong radiation, high-temperature, and high-pressure environment within the reactor are improved. This prevents measurement failure due to probe deformation, corrosion, or irradiation damage, extending the service life of the primary instrumentation.

[0035] The armored cable exits the irradiation device or reactor through a sealed interface containing a metal sealing flange and insulating sealant. The metal sealing flange achieves a physical seal at the reactor pressure boundary through rigid fastening, preventing leakage of radioactive media. The insulating sealant fills the interface gap to isolate electrical interference and ensure electrical isolation between the probe and the external environment. This dual structure jointly ensures the purity of the signal output and the safety of the seal. The insulating sealant can be made of materials such as ceramics or radiation-resistant polymers. The probe and armored cable are connected by welding or integrated pull-out connection, eliminating the risk of loosening of detachable connections (such as threads or clips) under long-term vibration and thermal cycling, forming a continuous and stable conductive path, and avoiding signal attenuation or interruption due to poor contact. This ensures the installation stability, signal output accuracy, and long-term operational reliability of the primary instrument in the extreme environment within the reactor.

[0036] The SPND (Special Nucleus Discharge Device) comprises a rhodium wire collector, an Al2O3 insulator, and an Inconel emitter. The Inconel emitter is nested within the rhodium wire collector and welded to the transmission cable. Electrical isolation between the Inconel emitter and the rhodium wire collector is achieved by filling with Al2O3 insulation. The Inconel emitter, rhodium wire collector, and Al2O3 insulator together form a cylindrical probe, which, after being welded to an armored signal cable, is pulled out to form an integrated in-pile primary instrument. This probe is connected to online measurement instruments via an armored cable coupling design. The emitter's nesting within the rhodium wire collector, with electrical isolation achieved by filling with Al2O3 insulation, avoids the risk of short circuits between the emitter and collector. Furthermore, the collector enhances the sensitivity of neutron fluence sensing by collecting and amplifying the emitted radiation signal. Simultaneously, the high-temperature stability and insulation properties of Al2O3 ensure consistent electrical performance under long-term irradiation.

[0037] The emitter and transmission cable are welded together, and the probe and armored signal cable are welded together and then pulled out to form an integrated structure. This eliminates the risk of loosening under vibration and thermal cycling in traditional detachable connections, forming a continuous, low-impedance conductive path and reducing signal attenuation and interference. The cylindrical probe's shape is adapted to the installation layout in the confined space within the reactor, and the integrated pull-out process with the armored cable enhances the overall mechanical strength of the probe, resisting material embrittlement or deformation caused by irradiation. In a preferred embodiment, the alloy combination of the Inconel emitter and the rhodium wire collector possesses excellent radiation resistance, enabling long-term stable operation in the strong neutron field within the reactor, avoiding measurement deviations caused by material activation or performance degradation. This ensures the structural integrity, signal sensing accuracy, and long-term operational reliability of the SPND as a primary instrument within the reactor under strong irradiation, high temperature, and high pressure environments, providing accurate and stable source data support for the online measurement of neutron flux, a key irradiation performance parameter.

[0038] The armored thermocouple includes a K-type armored thermocouple, an armored cable, a compensating wire, and a temperature acquisition module. The K-type armored thermocouple has an outer diameter of 1mm and is resistant to high temperature (1000℃), high pressure, and water / air media. The K-type armored thermocouple is connected to the compensating wire via the armored cable. The other end of the compensating wire is connected to the signal input terminal of the temperature acquisition module. The signal output terminal of the temperature acquisition module is connected to the signal processing unit integrated system via a network cable.

[0039] The K-type armored thermocouple features a miniaturized design with an outer diameter of 1mm, adaptable to the confined space within the reactor core, avoiding interference with the irradiation flow field or the test specimen. It also possesses adaptability to complex environments including 1000℃ high temperature, high pressure, and water / air media, enabling long-term stable operation in extreme temperature and pressure fluctuations and complex media within the reactor core, preventing measurement failure due to material oxidation, deformation, or performance degradation. The armored cable, serving as the connection carrier between the thermocouple and the compensating wire, combines mechanical protection and signal shielding functions, resisting in-core vibration, irradiation damage, and electromagnetic interference, ensuring the continuity of temperature signal transmission. The introduction of the compensating wire specifically corrects the cold junction temperature drift error of the thermocouple, and combined with the preliminary conditioning of the analog signal by the temperature acquisition module, improves the accuracy of the raw temperature data. The temperature acquisition module is integrated with the signal processing unit system via a network cable, achieving long-distance, low-loss transmission of digital signals, avoiding attenuation and crosstalk in traditional analog signal transmission, laying the foundation for subsequent integrated processing.

[0040] The fiber optic sensor comprises a grating assembly, an optical cable assembly, and a fiber optic demodulator. The grating assembly contains 12 sensors, connected to a 12-channel MT multi-path converter via 12 FC / APC connectors on the optical cable assembly. Each sensor integrates a strain sensor and a temperature sensor to measure strain or temperature values ​​at a single point. In an optional embodiment, the optical cable assembly includes a 100m fiber optic patch cord. One end of the cable assembly is connected to the grating assembly via the MT multi-path converter, and the other end is connected to the 12 demodulation channels of the fiber optic demodulator. The output of the fiber optic demodulator is connected to the integrated signal processing unit system via a signal cable. The grating or enamel cavity of the fiber optic sensor probe is fused to the fiber optic pigtail, armored in Inconel stainless steel tubing, and then passes through a protective tube and a sealing flange before exiting the irradiation device and reactor.

[0041] The grating assembly integrates 12 sensors, each with a single-point integrated strain and temperature sensor. These are connected to 12 MT multi-path transducers via 12 FC / APC connectors, forming a one-to-one correspondence between the 12 sensors and 12 channels. This architecture enables simultaneous sensing of deformation and temperature at multiple points on the test specimen, improving monitoring density and data correlation. Furthermore, centralized management via the multi-path transducers avoids signal crosstalk, ensuring the independence of individual measurements. The fiber optic cable assembly includes a 100m fiber optic patch cord, its length adapted to the spacing between the in-pile irradiation device and the signal processing unit. The flexible fiber optic material also possesses anti-electromagnetic interference properties, ensuring the stability of long-distance optical signal transmission. The fiber optic demodulator has 12 demodulation channels precisely matched to the 12 sensors, converting the light signals reflected from the grating / enamel cavity (corresponding to strain / temperature deformation) into electrical signals. The output is connected to the signal processing unit integrated system via a signal cable for subsequent digital signal processing.

[0042] In a preferred embodiment, after the grating or enamel cavity of the probe is fused to the fiber optic pigtail, it is armored through an Inconel stainless steel thin tube (high temperature resistant, radiation resistant, and corrosion resistant), and then passes through a protective tube and a sealing flange to exit the irradiation device and reactor. This armored structure protects against mechanical vibration and irradiation damage within the reactor, while the sealing flange provides physical isolation at pressure boundaries and ensures safe signal extraction. The fusion splicing eliminates the risk of optical loss from detachable interfaces. This ensures high-precision and high-stability online monitoring of deformation and temperature parameters by the fiber optic sensor under extreme reactor conditions, providing dense and reliable source data support for evaluating key performance indicators in fuel and material irradiation effect research.

[0043] The fiber optic sensor demodulator includes a demodulation module and a central processing unit. The demodulation module contains a beam splitter, a coupler, a wavelength-tunable light source module, a photodetector, an analog signal amplification circuit, an AD conversion circuit, and an FPGA demodulation module. All components are connected in series via an internal bus. The central processing unit contains a power supply module, processing circuits, storage circuits, a bus interface, and a conversion circuit. It is connected to the demodulation module via the bus interface. The demodulated electrical signal is processed by the central processing unit and then output to the signal processing unit integrated system via a signal cable.

[0044] The demodulation module connects the beam splitter, coupler, wavelength-tunable light source module, photodetector, analog signal amplification circuit, AD conversion circuit, and FPGA demodulation module via an internal bus, forming a coherent processing link of optical signal splitting - light source excitation - photoelectric conversion - amplification - digitization - high-speed demodulation. The internal bus centrally transmits control signals and data, reducing interference and signal attenuation from multiple nodes in traditional discrete connections, and improving the efficiency and stability of optical signal demodulation. The FPGA demodulation module, with its parallel computing capabilities, achieves high-frequency analysis of the wavelength of light reflected from the grating / enamel cavity, corresponding to strain or temperature deformation, meeting the real-time monitoring requirements of dynamic parameters in in-pile irradiation experiments. The wavelength-tunable light source module ensures light source stability through precise tuning, reducing ambient light interference.

[0045] The central processing unit integrates a power supply module, processing circuit, storage circuit, bus interface, and conversion circuit. Connected to the demodulation module via the bus interface, it monitors the demodulation process and configures parameters, while also performing noise reduction and normalization on the demodulated electrical signal to prevent glitches or drift in the original signal from affecting subsequent processing. The power supply module ensures stable power to all components, the processing circuit performs preliminary calculations on the demodulated electrical signal, the storage circuit temporarily stores intermediate data, the bus interface seamlessly interfaces with the demodulation module, and the conversion circuit adapts to the signal output format. In an optional embodiment, the processed electrical signal is output to the integrated signal processing unit system via a signal cable, forming a complete optical-electrical-digital conversion closed loop. This ensures efficient and accurate demodulation and electrical signal preprocessing of the optical signals from 12 sensors under complex electromagnetic and irradiation conditions within the stack, providing core conversion support for the fiber optic sensor's monitoring of deformation and temperature parameters.

[0046] Other current-type sensors include current-type sensor probes, multi-channel low-current amplifiers, ADCs, and microcontroller integrated circuits. The probe is connected to the input of the multi-channel low-current amplifier via an armored cable. The amplifier output is connected to the ADC input, the ADC output is connected to the microcontroller integrated circuit input, and the microcontroller integrated circuit output is connected to the signal processing unit integrated system via a network cable. The current-type sensor probe is connected to the multi-channel low-current amplifier via an armored cable. The high-temperature resistance, radiation resistance, and mechanical protection of the armored cable protect the probe from damage caused by strong radiation, high temperature and pressure, and vibration in the reactor core environment. It also shields against external electromagnetic interference, ensuring the pure extraction of weak current signals. The multi-channel low-current amplifier precisely amplifies the weak current signal output by the probe, increasing the signal amplitude to the range that the ADC can effectively sample, reducing the drowning effect of environmental noise on weak signals. The multi-channel design supports the simultaneous connection of multiple similar sensors, adapting to the needs of parallel monitoring of multiple parameters. The weak current signal is typically in the nA range.

[0047] The amplified analog signal is converted into a digital quantity by an ADC, achieving precise quantification of the current and laying the foundation for subsequent digital processing. A microcontroller integrated circuit performs preliminary processing of the digital signal; the integrated design reduces compatibility issues of discrete components and improves processing efficiency. This preliminary processing includes filtering, linearization calibration, and outlier removal. The microcontroller output transmits the processed digital signal to the signal processing unit integrated system via a network cable. The network cable's anti-interference capability and long-distance transmission stability prevent signal attenuation, ensuring complete data access to the backend system. This ensures high-sensitivity sensing, low-noise amplification, and reliable digital transmission of weak current signals by other current-type sensors (such as pressure and flow sensors) in the extreme environment within the reactor, providing accurate and stable source data support for online monitoring of various current-type parameters in irradiation experiments.

[0048] The LVDT includes a primary coil, a secondary coil, an iron core, a coil frame, a shell, a microcontroller integrated circuit, and a DC-to-AC module. There are at least two secondary coils. The primary coil is connected to the output of the DC-to-AC module, and the input of the DC-to-AC module is connected to the power supply. The iron core is mechanically connected to the test piece and moves within the coil frame as the test piece deforms. The outputs of the two secondary coils are connected to the input of the microcontroller integrated circuit, which integrates amplification, filtering, and demodulation functions. Its output is connected to the signal processing unit integrated system via armored cables.

[0049] The primary coil is connected to the output of the DC-to-AC module, converting the DC power supply into a high-frequency AC excitation signal input to the primary coil. This avoids zero-point drift under DC excitation and provides a stable energy source for the electromagnetic induction of the core and secondary coils, adapting to the complex power supply environment within the reactor. At least two secondary coils are provided, forming a differential structure. After the core is mechanically connected to the test piece, it moves within the coil frame with the deformation, changing the magnetic coupling strength of the two secondary coils and generating a differential voltage signal proportional to the displacement. The differential output design effectively cancels common-mode interference and improves the sensitivity and linearity of deformation measurement. The coil frame and the outer shell form a closed protective structure to resist damage to the coils from in-reactor radiation, high temperature, and mechanical vibration, ensuring the geometric stability of the core sensing unit.

[0050] Two secondary coil outputs are connected to a microcontroller integrated circuit with amplification, filtering, and demodulation functions. This circuit performs pre-amplification, bandpass filtering, and phase-sensitive demodulation on weak differential signals, ultimately outputting a digital signal proportional to the deformation. Pre-amplification improves the signal-to-noise ratio, bandpass filtering removes high-frequency noise and low-frequency drift, and phase-sensitive demodulation extracts displacement and phase information. The microcontroller output is connected to the signal processing unit integrated system via an armored cable, ensuring the signal is protected from electromagnetic interference and physical damage during long-distance transmission. This enables the LVDT to accurately capture micron-level deformation of the test specimen in extreme in-pile environments, providing highly reliable deformation data for research on key effects such as material / fuel irradiation swelling and creep.

[0051] The online measurement instrument coupling design includes a coordinated layout structure, a cable fixing structure, and a sealed connection structure. The coordinated layout structure is used for the relative positioning of the test specimen with SPND, armored thermocouples, fiber optic sensors, LVDT, and other current-type sensor probes. The cable fixing structure is used to fix the routing of armored signal cables within the irradiation device and prevent interference. The sealed connection structure is the transition interface between the armored cables and the irradiation device outlet and the pressure boundary of the reactor pressure vessel, including a double-layer metal sealing flange and ceramic insulating filler, to achieve physical isolation and signal conduction between the in-pile and out-of-pile environments.

[0052] The coordinated layout structure, by precisely positioning the relative positions of the test specimen and SPND, armored thermocouples, fiber optic sensors, LVDT, and other current-type sensor probes, avoids spatial interference and measurement blind spots between multiple probes, ensuring that each sensor is at its optimal sensing point and improving the measurement accuracy of multi-parameter spatial correlation. Optimal sensing points include, for example, the center of the neutron field for neutron fluence monitoring and the sensitive section of the test specimen for deformation monitoring. The cable fixing structure, by planning and fixing the routing of the armored signal cables within the irradiation device, prevents the cables from becoming entangled, worn, or broken due to in-pile vibration, thermal expansion, or irradiation creep, ensuring the long-term stability of the signal transmission path and reducing signal attenuation or interruption caused by cable displacement.

[0053] In a preferred embodiment, the sealed connection structure employs a transition interface containing a double-layer metal sealing flange and ceramic insulating filler. The double-layer metal flange enhances the sealing performance of the pressure boundary through rigid superposition, preventing leakage of radioactive media. The ceramic insulating filler fills the interface gap, achieving both in-core and out-of-core electrical isolation to avoid interference and ensuring low-impedance conduction of signal cables. This dual protection meets the stringent requirements of reactor pressure vessels for sealing and signal integrity. It addresses the pain points of traditional coupling designs, such as chaotic probe placement, fragile cables, and unreliable sealing, providing a standardized solution for the collaborative installation and signal extraction of multiple sensors in extreme in-core environments. This strengthens the one-stop access capability and long-term operational reliability of the entire multi-system integration technology in irradiation testing, laying a solid physical foundation for multi-parameter synchronous monitoring in materials / fuel irradiation effect research.

[0054] It also includes a method for online measurement of in-pile irradiation performance parameters, comprising the following steps: S1. Through online measurement instrument coupling design, the primary instrument probes of SPND, armored thermocouples, fiber optic sensors, LVDT, and other current-type sensors are coordinated with the test piece and sealed to the irradiation device and reactor pressure boundary via armored cables to achieve in-pile installation and signal extraction.

[0055] S1, through the coordinated arrangement and sealed connection of online measurement instrument coupling design, accurately positions multiple sensor probes in the sensitive areas of the test specimen. The signals from inside and outside the stack are safely extracted via armored cables, avoiding the spatial interference and sealing leakage risks of traditional decentralized installations, and laying the physical foundation for synchronous monitoring of multiple parameters.

[0056] S2. A redundant acquisition mode with one active and one standby is adopted. The voltage / current / optical signals output by the primary instrument are received by the integrated system through the signal processing unit, and then amplified, denoised, filtered and converted from analog to digital in sequence.

[0057] The S2 adopts a one-in-one-backup redundant acquisition mode, which seamlessly switches to the backup module when one acquisition module fails, ensuring the continuity of signal acquisition. At the same time, through coherent preprocessing of amplification, noise reduction, filtering and analog-to-digital conversion, it eliminates environmental noise and interference in the original signal and improves data purity.

[0058] S3 integrates nonlinear correction, simulation algorithms, and compensation algorithms to optimize the converted digital signal, obtaining neutron flux, temperature, pressure, and deformation parameters.

[0059] The S3 integrates nonlinear correction, simulation algorithms, and compensation algorithms to specifically correct sensor nonlinear errors, environmental temperature drift, and radiation interference. It optimizes the converted digital signal into key parameters such as neutron flux, temperature, pressure, and deformation, thereby improving measurement accuracy and adaptability.

[0060] S4. The processed parameters are transmitted to the host computer in the main control room via network cable. The real-time parameters and change curves are displayed on the process flow diagram through configuration software, and the parameters are stored, recorded and anomaly alarms are triggered synchronously.

[0061] S4 transmits data to the host computer in the main control room via network cable, and displays parameters and change curves in real time using configuration software. It also stores records and triggers abnormal alarms, enabling full-process visual monitoring and risk warning of the irradiation test, thus ensuring test safety.

[0062] S5 supports multi-parameter correlation analysis, allowing users to switch between displaying single-parameter curves and multi-parameter superimposed trends, providing data support for irradiation effect research.

[0063] S5 supports multi-parameter correlation analysis and single / multi-curve switching display, reflecting the intrinsic correlation between parameters, such as temperature-deformation coupling effects, providing multi-dimensional data support for the study of material / fuel irradiation swelling, creep, and other effects. It addresses the pain points of fragmented online measurement systems, signal vulnerability, coarse processing, and limited analysis, reducing experimental maintenance costs.

[0064] The implementation principle of this application embodiment is as follows: The primary instrumentation component integrates SPND, armored thermocouples, fiber optic sensors, LVDT, and other current-type sensors to achieve synchronous online sensing of multi-dimensional performance parameters such as neutron flux, temperature, pressure, and specimen deformation during irradiation tests. The online measurement instrument coupling design simplifies the complex process of distributed installation, reduces signal relay links, and lowers electromagnetic interference and transmission loss. At the same time, it ensures reliable sealed connection between the in-pile probe and the device, and the pressure boundary, guaranteeing the stability of signal extraction under extreme environments. The signal processing unit integrated system can seamlessly switch to the backup module when one module fails, improving the continuity and safety of system operation. At the same time, by integrating functions such as acquisition, amplification, noise reduction, filtering, and analog-to-digital conversion, it avoids compatibility issues of scattered equipment and optimizes signal processing accuracy and efficiency. The host computer in the main control room communicates with the integrated system, which can not only display multi-parameter data and plot change curves in real time to achieve full-process visual monitoring of the irradiation test, but also provide support for subsequent data analysis and algorithm iteration through data storage and recording functions.

[0065] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A multi-instrument centralized control integration technology for online measurement in in-pile irradiation tests, characterized in that, include: A primary instrumentation assembly, installed in the irradiation device within the reactor, is used for online sensing of irradiation performance parameters. The primary instrumentation assembly includes SPND, armored thermocouples, fiber optic sensors, LVDT, and other current-type sensors. Online measuring instruments, wherein the online measuring instruments are coupled in a design that enables the physical connection and signal extraction between the primary instrument components and the irradiation device and the reactor pressure boundary; The signal processing unit integrated system is used to receive voltage signals, current signals or optical signals output by primary instrument components, and transmit them to the host computer in the main control room after acquisition, amplification, noise reduction, filtering and analog-to-digital conversion. The host computer in the main control room is connected to the integrated system of the signal processing unit. The host computer in the main control room is used to receive and display the processed irradiation performance parameter data and can plot the parameter change curves. Among them, the primary instrument signal is directly connected to the irradiation device through a coupling design, and the signal cable is directly connected to the acquisition module of the integrated system cabinet; the signal processing unit integrated system adopts a one-in-one-backup redundant design.

2. The integrated technology for centralized control of multiple instruments for online measurement in in-pile irradiation tests according to claim 1, characterized in that, In the primary instrumentation assembly, the probes of each sensor are armored and integrated with the armored cables. The ends of the armored cables pass through a sealed interface designed for coupling with online measuring instruments, exiting the irradiation device or the reactor. The sealed interface includes a metal sealing flange and insulating sealing filler. The sealed interface is used to achieve in-pile installation and signal extraction. The connection method between each sensor probe and the armored cable is welding or integrated pull-out.

3. The integrated technology for centralized control of multiple instruments for online measurement in in-pile irradiation tests according to claim 2, characterized in that, The SPND includes a rhodium wire collector, an Al2O3 insulator, and an Inconel emitter. The Inconel emitter is nested inside the rhodium wire collector and is welded to the transmission cable. Electrical isolation between the Inconel emitter and the rhodium wire collector is achieved by filling with the Al2O3 insulator. The Inconel emitter, the rhodium wire collector, and the Al2O3 insulator together form a cylindrical probe, which is welded to an armored signal cable and then pulled out to form an integrated in-pile primary instrument. This probe is connected to an online measurement instrument via an armored cable.

4. The integrated technology for centralized control of multiple instruments for online measurement in in-pile irradiation tests according to claim 1, characterized in that, The armored thermocouple includes a K-type armored thermocouple, an armored cable, a compensating wire, and a temperature acquisition module. The K-type armored thermocouple has an outer diameter of 1mm and is resistant to high temperature (1000℃), high pressure, and water / air media. The K-type armored thermocouple is connected to the compensating wire via the armored cable. The other end of the compensating wire is connected to the signal input terminal of the temperature acquisition module. The signal output terminal of the temperature acquisition module is connected to the signal processing unit integrated system via a network cable.

5. The integrated technology for centralized control of multiple instruments for online measurement in in-pile irradiation tests according to claim 1, characterized in that, The fiber optic sensor includes a grating assembly, an optical cable assembly, and a fiber optic sensor demodulator; the grating assembly contains 12 sensors, which are connected to 12 MT multi-path converters through 12 FC / APC connectors of the optical cable assembly. Each sensor integrates a strain sensor and a temperature sensor to measure the strain or temperature value at a single point. The optical cable assembly includes a 100m optical fiber patch cord. One end of the optical cable assembly is connected to the grating assembly via an MT multi-path converter, and the other end of the optical cable assembly is connected to the 12 demodulation channels of the optical fiber sensor demodulator. The output end of the optical fiber sensor demodulator is connected to the signal processing unit integrated system via a signal cable. The grating or enamel cavity of the optical fiber sensor probe is fused with the optical fiber pigtail and then armored through an Inconel stainless steel thin tube, passing through a protective tube and a sealing flange before exiting the irradiation device and reactor.

6. The integrated technology for centralized control of multiple instruments for online measurement in in-pile irradiation tests according to claim 5, characterized in that, The fiber optic sensor demodulator includes a demodulation module and a central processing unit. The demodulation module comprises a beam splitter, a coupler, a wavelength-tunable light source module, a photodetector, an analog signal amplification circuit, an AD conversion circuit, and an FPGA demodulation module, all connected in series via an internal bus. The central processing unit comprises a power supply module, a processing circuit, a storage circuit, a bus interface, and a conversion circuit, and is connected to the demodulation module via the bus interface. The demodulated electrical signal is processed by the central processing unit and then output to the signal processing unit integrated system via a signal cable.

7. The integrated technology for centralized control of multiple instruments for online measurement in in-pile irradiation tests according to claim 1, characterized in that, The other current-type sensors include a current-type sensor probe, a multi-channel low-current amplifier, an ADC, and a microcontroller integrated circuit; the probe is connected to the input of the multi-channel low-current amplifier via an armored cable, the amplifier output is connected to the input of the ADC, the ADC output is connected to the input of the microcontroller integrated circuit, and the microcontroller integrated circuit output is connected to the signal processing unit integrated system via a network cable.

8. The integrated technology for centralized control of multiple instruments for online measurement in in-pile irradiation tests according to claim 1, characterized in that, The LVDT includes a primary coil, a secondary coil, an iron core, a coil frame, a shell, a microcontroller integrated circuit, and a DC-to-AC converter module, wherein there are at least two secondary coils; the primary coil is connected to the output terminal of the DC-to-AC converter module, and the input terminal of the DC-to-AC converter module is connected to a power supply; the iron core is mechanically connected to the test piece and moves within the coil frame as the test piece deforms; the output terminals of the two secondary coils are connected to the input terminals of the microcontroller integrated circuit, which integrates amplification, filtering, and demodulation functions, and its output terminal is connected to the signal processing unit integrated system through armored cables.

9. The integrated technology for centralized control of multiple instruments for online measurement in in-pile irradiation tests according to claim 1, characterized in that, The online measurement instrument coupling design includes a coordinated arrangement structure, a cable fixing structure, and a sealed connection structure. The coordinated arrangement structure is used for the relative positioning of the test specimen with SPND, armored thermocouples, fiber optic sensors, LVDT, and other current-type sensor probes. The cable fixing structure is used to fix the routing of the armored signal cables within the irradiation device and prevent interference. The sealed connection structure is the transition interface between the armored cables and the outlet of the irradiation device and the pressure boundary of the reactor pressure vessel, containing a double-layer metal sealing flange and ceramic insulating filler to achieve physical isolation and signal conduction between the in-pile and out-of-pile environments.

10. The method for online measurement of in-core irradiation performance parameters according to any one of claims 1-9, using a multi-instrument centralized control integration technology for online measurement of in-core irradiation tests, is characterized in that... Includes the following steps: S1. Through online measurement instrument coupling design, the primary instrument probes of SPND, armored thermocouple, fiber optic sensor, LVDT, and other current-type sensors are coordinated with the test piece and sealed to the irradiation device and reactor pressure boundary via armored cables to achieve in-pile installation and signal extraction. S2. A redundant acquisition mode with one active and one standby is adopted. The voltage / current / optical signals output by the primary instrument are received by the integrated system through the signal processing unit, and then amplified, denoised, filtered and converted from analog to digital in sequence. S3 integrates nonlinear correction, simulation algorithms, and compensation algorithms to optimize the converted digital signal and obtain neutron flux, temperature, pressure, and deformation parameters; S4. The processed parameters are transmitted to the host computer in the main control room via network cable. The real-time parameters and change curves are displayed on the process flow diagram through configuration software, and the parameters are stored, recorded and anomaly alarms are triggered synchronously. S5 supports multi-parameter correlation analysis, allowing users to switch between displaying single-parameter curves and multi-parameter superimposed trends, providing data support for irradiation effect research.

Images