An apparatus and method for irradiation testing of a small neutron detector

Abstract

This invention belongs to the field of nuclear technology applications, specifically relating to an apparatus and method for irradiation testing of a small neutron detector. It includes a detector assembly, signal cables, a detector signal amplifier, a primary secondary instrument cabinet, and a secondary secondary instrument cabinet. Both the primary and secondary instrument cabinets contain detector signal amplifiers, power modules, a main control card module, a power switch, an all-in-one computer, an AI module, and a power plug. The beneficial effects of this invention are: without affecting the safe operation of the reactor, it utilizes the spare channels of the heavy water reactor detector assembly to conduct online irradiation performance tests and long-term burnup tests of a small neutron detector. The tests determine the performance, burnup, and service life of the small neutron detector, while also meeting the key technological applications in scientific research and neutron detector fields.

Description

Technical Field

[0001] This invention belongs to the field of nuclear technology applications, specifically relating to a device and method for irradiating a small neutron detector. Background Technology

[0002] The CANDU heavy water reactor uses natural uranium as fuel. The reactor core is horizontally arranged, with heavy water as the moderator filling the piping container. Fuel channels are evenly distributed radially along the core, filled with fuel, and cooled by heavy water pumps to remove heat from the core. The heavy water reactor core is designed for neutron overmoderation, resulting in significant gaps between the fuel channels. Flux detector assemblies are inserted horizontally or vertically into these gaps, providing reactor control, protection, and measurement functions. Each detector assembly has a spare channel, and the neutron flux in the detector assembly area is as high as 2.0 × 10⁻⁶. 14 n / cm 2 With a flux of ·s or higher, it is an order of magnitude higher than that of a typical light water commercial or research reactor, reaching the level of a high-neutron research reactor. It can also operate stably at full power for a long time. The suitable space and high-neutron flux are very suitable for carrying out and quickly completing irradiation performance tests and long-term burnup tests of small neutron flux detectors such as platinum, vanadium, and rhodium self-powered detectors. However, there are no such devices and methods. Summary of the Invention

[0003] The purpose of this invention is to provide an apparatus and method for irradiation testing of a small neutron detector. The method utilizes the in-core measurement channels of a large commercial heavy water reactor to conduct irradiation performance tests and long-term burnup tests on the small neutron detector, and solves problems related to signal connection and signal acquisition of the small neutron detector, detector components and secondary instrument cabinet.

[0004] The technical solution of the present invention is as follows: A device for irradiation testing of a small neutron detector, comprising a detector assembly, a signal cable, a detector signal amplifier, a first secondary instrument cabinet and a second secondary instrument cabinet, wherein the first secondary instrument cabinet and the second secondary instrument cabinet are each provided with a detector signal amplifier, a power module, a main control card module, a power switch, an all-in-one computer, an AI module and a power plug.

[0005] The detector assembly is a circular stainless steel structure with a wiring compartment on top. The wiring compartment is equipped with a LEMO socket, a large aviation plug, a small aviation plug, and a medium aviation plug for connecting detector signals.

[0006] The detector assembly is installed in the pipe container. The detector assembly structure is inserted into the pipe container along the pipe container nozzle and guide tube extension of the pipe container shell. The protective tube is used to protect the guide tube extension. The guide tube positioner is installed in the pipe container shell to position the guide tube. The protective tube support is used to support the protective tube, the connector cover component, the capsule tube flange, the support component, the flange seal and the bellows assembly. The platform structure is used to support and seal the detector assembly. The detector capillary tube is inside the capsule tube inside the assembly. The aviation socket is used to connect the detector signal. The pipe of the pipe container is the pipe next to the detector assembly.

[0007] The aviation socket is used to extract the signal of the small detector from inside the detector assembly. The shielding wire installed on the spare channel is used to shield the reactor core from radiation such as neutrons and gamma rays. The LEMO socket is used to connect the small neutron detector. The plug of the small neutron detector is inserted into the LEMO socket to achieve signal connection.

[0008] The signal cable includes multiple signal cables, which are twisted-pair shielded cables. One end is connected to a large, small, or medium-sized aviation connector of the detector assembly, and the other end is connected to a detector signal amplifier. An existing detector signal amplifier is used to lead the detector signal to the detector signal amplifier located in the first and second secondary instrument cabinets.

[0009] The detector signal amplifier in the first and second instrument cabinet amplifies the current signal of the irradiated small neutron detector and converts it into a 0.5-4.5VDC voltage output. The detector signal amplifier can amplify current signals from 0.44 nanoamps to 2.6 microamps.

[0010] The AI ​​module in the primary and secondary instrument cabinet converts the 0.5-4.5VDC voltage signal into a digital signal and sends the digital signal into the main control card module.

[0011] The main control card module in the primary and secondary instrument cabinet receives digital signals from the AI ​​module and sends the digital signals to the all-in-one computer.

[0012] The power module in the primary and secondary instrument cabinet supplies power to the AI ​​module and the main control card module.

[0013] The all-in-one computer in the primary and secondary instrument cabinet receives and stores the digital signals sent by the main control card module;

[0014] The power switch in the primary and secondary instrument cabinet controls the power supply to the power module, detector signal amplifier, and all-in-one computer.

[0015] The second secondary instrument cabinet is equipped with a vanadium detector amplifier to amplify the current signal of the vanadium detector and convert it into a 0.5-4.5VDC voltage output;

[0016] In the secondary instrument cabinet, the AI ​​module converts the 0.5-4.5VDC voltage signal into a digital signal and sends the digital signal into the main control card module.

[0017] The main control card module in the secondary instrument cabinet receives digital signals from the AI ​​module and sends the digital signals to the all-in-one computer.

[0018] The power module in the secondary instrument cabinet supplies power to the AI ​​module and the main control card module.

[0019] The all-in-one computer in the secondary instrument cabinet receives and stores the digital signals sent by the main control card module;

[0020] The power switch in the secondary instrument cabinet controls the power supply to the power module, vanadium detector amplifier, and all-in-one computer.

[0021] The power plug is used to insert into an external power socket to supply power to the secondary instrument cabinet.

[0022] A method for irradiating a small neutron detector includes the following steps:

[0023] Step 1: Insert the multiple self-powered detectors to be irradiated into the measurement channels of the detector assembly located in the reactor core;

[0024] Step 2: Insert the signal plugs of the multiple self-powered detectors to be irradiated into the LEMO socket of the detector assembly;

[0025] Step 3: Insert multiple existing accurate detectors into the measurement channels of the detector assembly;

[0026] Step 4: Insert the signal plugs of multiple existing accurate detectors into the LEMO socket;

[0027] Step 5: Lay multiple signal cables. Connect the large, medium, and small aviation plugs of the detector assembly to one end of the signal cables.

[0028] Step 6: Measure the impedance and capacitance of the irradiated detector and the vanadium detector at the other end of the multiple signal cables.

[0029] Step 7: After the measurement is qualified, connect the other ends of the multiple signal cables to the signal amplifiers of multiple detectors and the vanadium detector amplifier respectively;

[0030] Step 8: Plug both power cords into the external power outlet;

[0031] Step 9: Turn on the power switch of the secondary instrument cabinet to supply power to the amplifier, power module and all-in-one computer, and confirm that the all-in-one computer can correctly record the signals of the irradiated detector and vanadium detector.

[0032] Step 10: The detector assembly itself is located in the reactor core. During reactor startup, the detector signal will gradually increase as the reactor power increases. At the same time, the integrated computer records the signals of the irradiated small neutron detector and the existing accurate detector.

[0033] Step 11: During the long-term stable operation of the reactor, the integrated computer records the long-term signals of the irradiated detectors and the existing accurate detectors.

[0034] Step 12: Compare and analyze the signals recorded by the all-in-one computer from the irradiated detector with those from existing accurate detectors to complete the data analysis of the irradiation performance test and long-term burnup test of the small neutron detector, and the data from existing accurate detectors can be used for comparative analysis.

[0035] The beneficial effects of this invention are as follows: Without affecting the safe operation of the reactor, online irradiation performance and long-term burnup tests of a small neutron detector are conducted using the spare channel of the heavy water reactor detector assembly. These tests determine the performance, burnup, and service life of the small neutron detector, while also meeting the key technical application needs in scientific research and neutron detector fields. The small neutron detector is installed using the spare channel of the heavy water reactor detector assembly, and its signals are transmitted to the secondary instrument cabinet. The detector signals are then collected and recorded, facilitating analysis and processing of the collected signal data by research institutions. Attached Figure Description

[0036] Figure 1 A schematic diagram of a device for irradiating a small neutron detector provided by the present invention;

[0037] Figure 2 This is a schematic diagram of the detector assembly.

[0038] Figure 3 for Figure 2 Sectional view along line AA;

[0039] Figure 4 for Figure 2 Sectional view along the BB direction.

[0040] In the diagram: 1. Aviation socket, 2. Detector channel, 3. Pipeline container tube, 4. Capsule tube, 5. Guide tube, 6. Guide tube positioner, 7. Pipeline container housing, 8. Connector cover assembly, 9. Capsule tube flange, 10. Support, 11. Flange seal, 12. Bellows assembly, 13. Platform structure, 14. Protective tube support, 15. Protective tube, 16. Guide tube extension, 17. Pipeline container nozzle, 18. Pipeline container housing, 21. Aviation detector, 22. Shielding wire, 23. LEMO socket, 25. Helium filling interface, 26. TFD channel. Detailed Implementation

[0041] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0042] The large commercial heavy water reactor has up to 33 on-board detector assemblies, 363 measurement channels, and 175 spare channels. It can simultaneously conduct irradiation tests on multiple small neutron detectors using the spare channels without requiring the development of dedicated detector fixtures or similar devices. The large commercial heavy water reactor can operate continuously at full power high neutron flux levels for up to two years, enabling continuous and rapid irradiation tests on the detectors. The detector assembly channels are sealed and covered with 100 kPa of helium gas, maintaining a suitable temperature of approximately 75°C. Furthermore, it allows for comparison using data from existing, accurate detector measurements.

[0043] After the multiple small neutron detectors requiring irradiation are installed, their signal plugs are connected to the LEMO plugs located in the detector assembly. The detector signals are then led out through the large, medium, or small aviation plugs of the detector assembly and sent to the detector signal amplifiers located in the first and second secondary instrument cabinet 1 via signal cables. The detector signal amplifiers amplify the signals and send the voltage signals to the AI ​​module located in the first and second secondary instrument cabinet 1. The AI ​​module performs analog-to-digital conversion. After conversion, the data is sent to the main control card module located in the first and second secondary instrument cabinet 1. The main control card module sends the data signals to the all-in-one computer located in the first and second secondary instrument cabinet 1. The all-in-one computer stores the collected data for data analysis of the detectors requiring irradiation.

[0044] The signal plugs of multiple existing accurate detectors are connected to the LEMO plug located on the detector assembly. The detector signals are then led out via large, medium, or small aviation plugs on the detector assembly and sent to amplifiers located in the second secondary instrument cabinet 2 via signal cables. The amplifiers amplify the signals and send the voltage signals to the AI ​​module in the second secondary instrument cabinet 2. The AI ​​module performs analog-to-digital conversion. After conversion, the data is sent to the main control card module in the second secondary instrument cabinet 2. The main control card module sends the data signals to the all-in-one computer in the second secondary instrument cabinet 2. The all-in-one computer stores the collected data as comparative data for the analysis of the detector data to be irradiated. Based on the signals from multiple accurate detectors, the flux of this area is calculated. Based on the flux, the burnup and other data of the multiple detectors requiring irradiation assessment can be calculated.

[0045] like Figure 1 As shown, a device for irradiation testing of a small neutron detector includes a detector assembly, a signal cable, a detector signal amplifier, a first secondary instrument cabinet and a second secondary instrument cabinet. Both the first secondary instrument cabinet and the second secondary instrument cabinet are equipped with detector signal amplifiers, power modules, main control card modules, power switches, all-in-one computers, AI modules and power plugs.

[0046] The detector assembly is a circular stainless steel structure with a wiring compartment at the top, located at the top of the reactor core. The lower capsule tube and detector channels penetrate the entire core. The wiring compartment contains LEMO sockets, large aviation connectors, small aviation connectors, and medium aviation connectors for connecting detector signals. It contains 11 channels for installing multiple small neutron detectors requiring irradiation and multiple accurate detectors, and for extracting detector signals. Large commercial heavy water reactors have 33 detector assemblies with a total of 363 measurement channels, including 175 spare measurement channels, allowing for simultaneous irradiation testing of multiple small neutron detectors.

[0047] like Figure 2 As shown, the detector assembly is installed in the pipe container. The detector assembly structure is inserted into the pipe container along the pipe container nozzle 17 and guide tube extension 16 of the pipe container shell 18. The protective tube 15 is used to protect the guide tube extension 16. The guide tube positioner 6 is installed on the pipe container shell 7 to position the guide tube 5. The protective tube support 14 is used to support the protective tube 15. The connector cover component 8, capsule tube flange 9, support component 10, flange seal 11, bellows assembly 12, and platform structure 13 are used to support and seal the detector assembly. The detector capillary tube 2 is inside the capsule tube 4 inside the assembly and is used to install a small neutron detector. The aviation socket 1 is used to connect the detector signal. The pipe container pipe 3 is the pipe on the side of the detector assembly.

[0048] Figure 3 for Figure 2 Cross-sectional view along axis AA: Aviation socket 1 is used to extract signals from the detector assembly from within the small detector. Shielding wire 22, installed on the spare channel, is used to shield against neutron and gamma-ray radiation from the reactor core. LEMO socket 23 is used for connecting the small neutron detector; the plug of the small neutron detector is inserted into the LEMO socket to establish signal connection. Detector channel 2 is used to install the small neutron detector. Helium filling interface 25 is used to fill the detector assembly with helium to protect the internal detector. TFD channel 26 is used to install a small fission detector.

[0049] Figure 4 for Figure 2 The BB-shaped cross-sectional view shows the capsule tube 4 on the outside and the detector channel 2 on the inside.

[0050] The signal cable comprises multiple signal cables, which are twisted-pair shielded cables. One end connects to a large, small, or medium-sized aviation connector on the detector assembly, and the other end connects to an existing detector signal amplifier. This is used to route the detector signal to the detector signal amplifier located in the first and second secondary instrument cabinets.

[0051] The detector signal amplifier located in the first and second instrument cabinet 1 amplifies the current signal of the irradiated small neutron detector and converts it into a 0.5-4.5VDC voltage output. The detector signal amplifier can amplify current signals from 0.44 nanoamps to 2.6 microamps.

[0052] The AI ​​module located in the first and second instrument cabinet 1 converts the 0.5-4.5VDC voltage signal into a digital signal and sends the digital signal into the main control card module.

[0053] The main control card module located in the first and second instrument cabinet 1: receives digital signals from the AI ​​module and sends the digital signals to the all-in-one computer.

[0054] The power supply module located in the first and second instrument cabinet 1 supplies power to the AI ​​module and the main control card module.

[0055] The all-in-one computer located in the first and second instrument cabinet 1: receives digital signals sent by the main control card module and stores the digital signals.

[0056] The power switch located in the first and second instrument cabinet 1 controls the power supply to the power module, detector signal amplifier and all-in-one computer.

[0057] The vanadium detector amplifier located in the second secondary instrument cabinet 2 amplifies the current signal of the vanadium detector and converts it into a 0.5-4.5VDC voltage output.

[0058] The AI ​​module located in the second secondary instrument cabinet 2 converts the 0.5-4.5VDC voltage signal into a digital signal and sends the digital signal into the main control card module.

[0059] The main control card module located in the second secondary instrument cabinet 2: receives digital signals from the AI ​​module and sends the digital signals to the all-in-one computer.

[0060] The power module located in the second secondary instrument cabinet 2 supplies power to the AI ​​module and the main control card module.

[0061] The all-in-one computer located in the second secondary instrument cabinet 2: receives digital signals sent by the main control card module and stores the digital signals.

[0062] The power switch located in the second secondary instrument cabinet 2 controls the power supply to the power module, vanadium detector amplifier, and all-in-one computer.

[0063] The power plug is used to insert into an external power socket to supply power to the secondary instrument cabinet.

[0064] A method for irradiating a small neutron detector includes the following steps:

[0065] Step 1: Insert the multiple self-powered detectors to be irradiated into the measurement channels of the detector assembly located in the reactor core;

[0066] Step 2: Insert the signal plugs of the multiple self-powered detectors to be irradiated into the LEMO socket of the detector assembly;

[0067] Step 3: Insert multiple existing accurate detectors into the measurement channels of the detector assembly;

[0068] Step 4: Insert the signal plugs of multiple existing accurate detectors into the LEMO socket;

[0069] Step 5: Lay multiple signal cables. Connect the large, medium, and small aviation plugs of the detector assembly to one end of the signal cables.

[0070] Step 6: Measure the impedance and capacitance of the irradiated detector and the vanadium detector at the other end of the multiple signal cables.

[0071] Step 7: After the measurement is qualified, connect the other ends of the multiple signal cables to the signal amplifiers of multiple detectors and the vanadium detector amplifier respectively;

[0072] Step 8: Plug both power cords into the external power outlet;

[0073] Step 9: Turn on the power switches of secondary instrument cabinets 1 and 2 to supply power to the amplifier, power module and all-in-one computer, and confirm that the all-in-one computer can correctly record the signals of the irradiated detector and vanadium detector.

[0074] Step 10: The detector assembly itself is located in the reactor core. During reactor startup, the detector signal will gradually increase as the reactor power rises. At the same time, the integrated computer records the signals of the irradiated small neutron detector and the existing accurate detector.

[0075] Step 11: During the long-term stable operation of the reactor, the integrated computer records the long-term signals of the irradiated detectors and the existing accurate detectors.

[0076] Step 12: Compare and analyze the signals recorded by the all-in-one computer from the irradiated detector with those from existing accurate detectors to complete the data analysis of the irradiation performance test and long-term burnup test of the small neutron detector, and the data from existing accurate detectors can be used for comparative analysis.

[0077] The present invention allows for irradiation of a small neutron detector without affecting the normal operation of the reactor. The signal from the small neutron detector can be transmitted to a secondary cabinet via cable for signal amplification and recording. Simultaneously, power-up tests of the small neutron detector can be conducted during the power-up of a large commercial heavy water reactor, and irradiation performance tests and long-term burnup tests can be performed during reactor operation. Furthermore, existing accurate detectors can be used for signal comparison and analysis.

[0078] Innovatively, the spare measurement channels of the detector assembly are utilized, taking advantage of their location within the reactor core, to conduct irradiation tests on small neutron detectors. Simultaneously, power-up tests of small neutron detectors can be conducted during the startup phase after a major overhaul of a large commercial heavy water reactor.

[0079] This device and method can conveniently conduct irradiation tests, irradiation performance tests, and long-term burnup tests on various newly developed small neutron detectors, such as platinum self-powered detectors, vanadium self-powered detectors, and rhodium self-powered detectors.

[0080] This device and method can be used to quickly complete the irradiation test of a small neutron detector, achieving the same test effect as a 7-10 year test of a light water reactor in one year.

Claims

1. A device for irradiation testing of a small neutron detector, characterized in that: It includes detector components, signal cables, detector signal amplifiers, primary and secondary instrument cabinets, and secondary instrument cabinets. Both the primary and secondary instrument cabinets are equipped with detector signal amplifiers, power modules, main control card modules, power switches, all-in-one computers, AI modules, and power plugs. The detector assembly is a circular stainless steel structure with a wiring compartment on top. The wiring compartment is equipped with a LEMO socket, a large aviation plug, a small aviation plug, and a medium aviation plug for connecting detector signals. The detector assembly is installed in the pipe container. The detector assembly structure is inserted into the pipe container along the pipe container nozzle and guide tube extension of the pipe container shell. The protective tube is used to protect the guide tube extension. The guide tube positioner is installed in the pipe container shell to position the guide tube. The protective tube support is used to support the protective tube, the connector cover component, the capsule tube flange, the support component, the flange seal and the bellows assembly. The platform structure is used to support and seal the detector assembly. The detector capillary tube is inside the capsule tube inside the assembly. The aviation socket is used to connect the detector signal. The pipe of the pipe container is the pipe next to the detector assembly.

2. The device for irradiation testing of a small neutron detector as described in claim 1, characterized in that: The aviation socket is used to extract the signal of the small detector from inside the detector assembly. The shielding wire installed on the spare channel is used to shield the neutron and gamma-ray radiation of the reactor core. The LEMO socket is used for connecting the small neutron detector. The plug of the small neutron detector is inserted into the LEMO socket to achieve signal connection.

3. The device for irradiation testing of a small neutron detector as described in claim 1, characterized in that: The signal cable includes multiple signal cables, which are twisted-pair shielded cables. One end is connected to a large, small, or medium-sized aviation connector of the detector assembly, and the other end is connected to a detector signal amplifier. An existing detector signal amplifier is used to lead the detector signal to the detector signal amplifier located in the first and second secondary instrument cabinets.

4. The device for irradiation testing of a small neutron detector as described in claim 1, characterized in that: The detector signal amplifier in the first and second instrument cabinet amplifies the current signal of the irradiated small neutron detector and converts it into a 0.5-4.5VDC voltage output. The detector signal amplifier can amplify current signals from 0.44 nanoamps to 2.6 microamps. The AI ​​module in the primary and secondary instrument cabinet converts the 0.5-4.5VDC voltage signal into a digital signal and sends the digital signal into the main control card module. The main control card module in the primary and secondary instrument cabinet receives digital signals from the AI ​​module and sends the digital signals to the all-in-one computer. The power module in the primary and secondary instrument cabinet supplies power to the AI ​​module and the main control card module. The all-in-one computer in the primary and secondary instrument cabinet receives and stores the digital signals sent by the main control card module; The power switch in the primary and secondary instrument cabinet controls the power supply to the power module, detector signal amplifier, and all-in-one computer.

5. The apparatus for irradiation testing of a small neutron detector as described in claim 1, characterized in that: The second secondary instrument cabinet is equipped with a vanadium detector amplifier to amplify the current signal of the vanadium detector and convert it into a 0.5-4.5VDC voltage output. In the secondary instrument cabinet, the AI ​​module converts the 0.5-4.5VDC voltage signal into a digital signal and sends the digital signal into the main control card module. The main control card module in the secondary instrument cabinet receives digital signals from the AI ​​module and sends the digital signals to the all-in-one computer. The power module in the secondary instrument cabinet supplies power to the AI ​​module and the main control card module. The all-in-one computer in the secondary instrument cabinet receives and stores the digital signals sent by the main control card module. The power switch in the secondary instrument cabinet controls the power supply to the power module, vanadium detector amplifier, and all-in-one computer. The power plug is used to insert into an external power socket to supply power to the secondary instrument cabinet.

6. A method for irradiating a small neutron detector, characterized in that, Includes the following steps: Step 1: Insert the multiple self-powered detectors to be irradiated into the detector channels of the detector assembly located in the reactor core; Step 2: Insert the signal plugs of the multiple self-powered detectors to be irradiated into the LEMO socket of the detector assembly; Step 3: Insert multiple existing accurate detectors into the detector channels of the detector assembly; Step 4: Insert the signal plugs of multiple existing accurate detectors into the LEMO socket; Step 5: Lay multiple signal cables and connect the large, medium, and small aviation plugs of the detector assembly to one end of the signal cables; Step 6: Measure the impedance and capacitance of the irradiated detector and the vanadium detector at the other end of the multiple signal cables. Step 7: After the measurement is qualified, connect the other ends of the multiple signal cables to the signal amplifiers of multiple detectors and the vanadium detector amplifier respectively; Step 8: Plug both power cords into the external power outlet; Step 9: Turn on the power switch of the secondary instrument cabinet to supply power to the amplifier, power module and all-in-one computer, and confirm that the all-in-one computer can correctly record the signals of the irradiated detector and vanadium detector. Step 10: The detector assembly itself is located in the reactor core. During reactor startup, the detector signal will gradually increase as the reactor power increases. At the same time, the integrated computer records the signals of the irradiated small neutron detector and the existing accurate detector. Step 11: During the long-term stable operation of the reactor, the integrated computer records the long-term signals of the irradiated detectors and the existing accurate detectors. Step 12: Compare and analyze the signals recorded by the all-in-one computer from the irradiated detector with those from existing accurate detectors to complete the data analysis of the irradiation performance test and long-term burnup test of the small neutron detector, and the data from existing accurate detectors can be used for comparative analysis.

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