Nuclear power plant power distribution measurement method, device and system

Abstract

The present application relates to a method, device, and system for measuring power distribution in a nuclear power plant. The method includes obtaining the initial reactivity of the reactor when a control rod is adjusted from within the reactor core to the top of the core, obtaining the final reactivity of the reactor when the control rod is adjusted from within the core to the bottom of the core, and obtaining the radial power distribution of the core using the initial and final reactivity values ​​and the theoretical power of the control rod assembly corresponding to the control rod. Compared to conventional technologies, the above method can measure the power distribution of the core in a zero-power physical test platform, thereby improving the accuracy of power distribution measurement in the zero-power physical test platform.

Description

Technical Field

[0001] The present application relates to the field of nuclear energy technology, and in particular to a method, device and system for measuring power distribution in a nuclear power plant. Background Art

[0002] The reactor core, also known as the active region, consists of fuel assemblies mounted on a gridded core frame. Core power distribution is a crucial parameter in reactor physics analysis and forms the basis for reactor design, safety analysis, fault diagnosis, and reactor control.

[0003] Traditionally, mobile neutron detection systems, such as pneumatic float systems, and fixed neutron detection systems, such as self-powered neutron detection systems, have been used to measure core power distribution. However, existing technologies are unable to measure power distribution during zero-power physical testing of third-generation nuclear power plants. Summary of the Invention

[0004] Based on this, it is necessary to provide a nuclear power plant power distribution measurement method, device and system to address the above technical issues.

[0005] A method for measuring power distribution in a nuclear power plant, comprising:

[0006] obtaining a value of the initial reactivity of the reactor when the control rod is adjusted from within the core of the reactor to the top of the core;

[0007] Obtaining the terminal reactivity value of the reactor when the control rod is adjusted from inside the core to the bottom of the core;

[0008] The radial power distribution of the core is obtained by the value of the initial reactivity, the value of the final reactivity and the theoretical power of the control rod assembly corresponding to the control rod.

[0009] In one embodiment, obtaining a value of initial reactivity of a reactor when a control rod is adjusted from within a core of the reactor to a top of the core includes:

[0010] Controlling the adjustment of the control rods from their initial position within the core to the top of the core;

[0011] When the reactivity of the reactor is stable, the value of the initial reactivity is obtained.

[0012] In one embodiment, obtaining a terminal reactivity value of a reactor when a control rod is adjusted from within the core to the bottom of the core includes:

[0013] Control rods are adjusted from their initial position within the core to the bottom of the core;

[0014] When the reactivity of the reactor is stable, the value of the final reactivity is obtained.

[0015] In one embodiment, the reactor core includes a plurality of control rod assemblies; after obtaining the initial reactivity value and the final reactivity value of the current control rod, the method further includes:

[0016] Control the current control rods from the bottom of the core to the top of the core;

[0017] The step of obtaining the value of the initial reactivity of the reactor when the control rod is adjusted from the inside of the reactor core to the top of the reactor core is continued for each of the other control rods until the values ​​of the initial reactivity and the final reactivity of all the control rods are obtained, thereby obtaining the radial power distribution of the core based on the values ​​of the initial reactivity and the final reactivity of all the control rods and the theoretical powers of the control rod assemblies corresponding to all the control rods.

[0018] In one embodiment, obtaining the radial power distribution of the core according to the initial reactivity value, the final reactivity value, and the theoretical power of the control rod assembly corresponding to the control rod includes:

[0019] Determine the single-rod measurement value of each control rod by using the initial reactivity value and the final reactivity value of each control rod;

[0020] Determine the value coefficient of each control rod based on the single-rod measured value and the single-rod theoretical value of each control rod;

[0021] The measured power of the control rod assembly corresponding to each control rod is determined as the product of the theoretical power of the control rod assembly corresponding to each control rod and the value coefficient;

[0022] The radial power distribution of the core is obtained by preprocessing the measured powers of the control rod assemblies corresponding to all control rods.

[0023] In one embodiment, determining a value coefficient for each control rod based on a measured value and a theoretical value of each control rod includes:

[0024] The value coefficient of each control rod is obtained by taking the square root of the quotient of the single-rod measured value of each control rod and the single-rod theoretical value of each control rod.

[0025] In one embodiment, the core includes control rod assemblies and non-control rod assemblies;

[0026] The radial power distribution of the core is obtained by preprocessing the measured power of the control rod assemblies corresponding to all control rods, including:

[0027] Fitting the measured power of non-control rod assemblies by the measured power of all control rod assemblies;

[0028] The measured powers of all control rod assemblies and all non-control rod assemblies are normalized to obtain the radial power distribution of the core.

[0029] A power distribution measuring device for a nuclear power plant, comprising:

[0030] an initial reactivity acquisition module, configured to acquire a value of the initial reactivity of the reactor when the control rod is adjusted from the reactor core to the top of the reactor core;

[0031] A terminal reactivity acquisition module is used to obtain the terminal reactivity value of the reactor when the control rod is adjusted from the inside of the core to the bottom of the core;

[0032] The power acquisition module is used to obtain the radial power distribution of the core through the value of the initial reactivity, the value of the final reactivity and the theoretical power of the control rod assembly corresponding to the control rod.

[0033] A nuclear power plant power distribution measurement system, the system comprising: data acquisition equipment and digital experimental simulation equipment;

[0034] A data acquisition device is used to collect the initial reactivity value and the final reactivity value of the reactor and send them to the digital experimental simulation device;

[0035] The digital experimental simulation device is used to execute the steps in any embodiment of the above-mentioned nuclear power plant power distribution measurement method.

[0036] In one embodiment, the system further comprises: a control rod drive system;

[0037] The control rod drive system is used to control the control rods to be adjusted from the core of the reactor to the top or bottom of the core, so that the data acquisition equipment can collect the initial reactivity value and the final reactivity value of the reactor.

[0038] The above-mentioned nuclear power plant power distribution measurement method, device and system include obtaining the value of the initial reactivity of the reactor when the control rod is adjusted from the core of the reactor to the top of the core, obtaining the value of the final reactivity of the reactor when the control rod is adjusted from the core to the bottom of the core, and obtaining the radial power distribution of the core through the value of the initial reactivity, the value of the final reactivity and the theoretical power of the control rod assembly corresponding to the control rod; compared with traditional technology, the above-mentioned method can realize the power distribution measurement of the core in a zero-power physical test platform, thereby improving the accuracy of power distribution measurement in the zero-power physical test platform. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A diagram showing the internal structure of a digital experiment simulation device in one embodiment;

[0040] Figure 2 1 is a flow chart of a method for measuring power distribution in a nuclear power plant according to an embodiment;

[0041] Figure 3 A schematic flow chart of a method for obtaining an initial reactivity value in one embodiment;

[0042] Figure 4 A schematic flow chart of a method for obtaining a final reactivity value in another embodiment;

[0043] Figure 5 A schematic flow chart of a method for obtaining radial power distribution of a reactor core in another embodiment;

[0044] Figure 6 A schematic flow chart of a method for determining a reaction deviation value of each control rod in another embodiment;

[0045] Figure 7 FIG. 4 is a structural block diagram of a power distribution measurement device for a nuclear power plant in one embodiment. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0047] The power distribution measurement method of nuclear power plants provided in this application can be applied to Figure 1 The digital experimental simulation device shown. The digital experimental simulation device includes a processor, a memory, a network interface, a display screen and an input device connected via a system bus. The processor of the digital experimental simulation device is used to provide computing and control capabilities. The memory of the digital experimental simulation device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the digital experimental simulation device is used to store the reactivity of the reactor at different times. The network interface of the digital experimental simulation device is used to communicate with an external terminal via a network connection. When the computer program is executed by the processor, a power distribution measurement method is implemented.

[0048] Those skilled in the art will understand that Figure 1 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the digital experimental simulation equipment to which the scheme of the present application is applied. The specific digital experimental simulation equipment may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0049] It should be noted that the nuclear power plant power distribution measurement method provided in the embodiments of this application is applicable to measuring the radial power distribution of a reactor core in a zero-power physical test platform. The method can be performed by a nuclear power plant power distribution measurement device, which can be implemented as part or all of a digital experimental simulation device through software, hardware, or a combination of software and hardware. The following embodiments illustrate the implementation process for using a digital experimental simulation device to perform core power distribution measurement.

[0050] In order to realize the measurement of power distribution in the zero-power physical test platform of the third-generation nuclear power unit, this application provides a method for measuring power distribution of a nuclear power plant, such as Figure 2 As shown, the method may include the following steps:

[0051] S100. Obtaining a value of the initial reactivity of the reactor when the control rod is adjusted from the inside of the reactor core to the top of the reactor core.

[0052] Specifically, the digital experimental simulation equipment can simulate a nuclear power unit operating on a zero-power physical test platform and simulate critical reactor test data to measure the power distribution of the reactor core. This reactor can be called an atomic reactor, a device capable of maintaining a controlled, self-sustaining chain nuclear fission reaction to achieve nuclear energy utilization. The core top can be understood as the reactor roof.

[0053] It should be noted that the reactor described above can, through the rational arrangement of nuclear fuel, enable a self-sustaining chain nuclear fission process to occur within it without the need for additional neutron sources. The reactor is also known as the heart of a nuclear power plant. The reactor may include a core, a structure, control rods, and a shield. The structure may include the fuel cladding, a core grid for housing the core, and a reactor pressure vessel. The shield is used to attenuate the various radiation generated by the reactor core, allowing neutrons generated during the reactor reaction to be slowed down and absorbed by the shield. The control rods can compensate for and regulate neutron reactivity within the reactor, as well as aid in emergency shutdowns, thereby regulating the reaction rate. The control rods are made of neutron-absorbing materials, typically boron, boron carbide, cadmium, silver-indium-cadmium, and the like.

[0054] It will be appreciated that the aforementioned reactor reactivity can be a physical quantity reflecting the reactor state, indicating the degree to which the reactor deviates from criticality. The initial reactivity can be the reactor reactivity corresponding to when the control rods are adjusted to the top of the core. The digital experimental simulation device can retrieve pre-stored initial reactor reactivity values ​​from a cloud or local location.

[0055] S200. Obtain a terminal reactivity value of the reactor when the control rod is adjusted from inside the core to the bottom of the core.

[0056] In this embodiment, before the control rod positions are adjusted in S100 and S200, the reactor reactivity values ​​can be the same. After the same control rods are adjusted to different positions, the reactor reactivity can be the same or different. The reactor can be a commercial pressurized water reactor. Optionally, the core bottom can be understood as the reactor bottom. The digital experimental simulation device can obtain pre-stored final reactor reactivity values ​​from a cloud or local location.

[0057] S300. Obtain radial power distribution of the core through the value of the initial reactivity, the value of the final reactivity, and the theoretical power of the control rod assembly corresponding to the control rod.

[0058] It is understood that the digital experimental simulation equipment can perform arithmetic operations, comparisons, numerical conversions, and / or normalization on the initial reactivity value, the final reactivity value, and the theoretical power of the control rod assembly corresponding to the control rod to obtain the radial power of the core, and further obtain the radial power distribution of the core based on the radial power of the core. The reactor core may include multiple control rod assemblies. Optionally, the control rod assembly can be understood as a nuclear fuel assembly with control rods; a control rod assembly is in contrast to a non-control rod assembly, which can be understood as a nuclear fuel assembly without control rods.

[0059] In the above-mentioned nuclear power plant power distribution measurement method, the value of the initial reactivity of the reactor when the control rod is adjusted from the core of the reactor to the top of the core can be obtained, and the value of the final reactivity of the reactor when the control rod is adjusted from the core to the bottom of the core can be obtained. The radial power distribution of the core can be obtained through the value of the initial reactivity, the value of the final reactivity and the theoretical power of the control rod assembly corresponding to the control rod; this method is not only applicable to the power distribution measurement of the core of first- and second-generation nuclear power units, but also to the power distribution measurement of the core of third-generation nuclear power units, thereby making the power distribution measurement method more reliable and more applicable; at the same time, compared with traditional technologies, the above-mentioned method can realize the power distribution measurement of the core in a zero-power physical test platform, thereby improving the accuracy of the power distribution measurement in the zero-power physical test platform, so that the measured power distribution is consistent with the theoretical power distribution, and avoiding the single rod value exceeding the standard during the zero-power physical test.

[0060] As one example, Figure 3 As shown, the step of obtaining the value of the initial reactivity of the reactor when the control rod is adjusted from the reactor core to the top of the reactor core in the above S100 can be achieved by the following steps:

[0061] S110 , controlling and adjusting the control rods from an initial position in the core to the core top.

[0062] In this embodiment, the digital experimental simulation device can send an initial position adjustment command to a control rod drive system (CRDS) with control rods inserted, instructing the CRDS to adjust any bundle of control rods inserted into the reactor core from their initial position within the core to the core top. Optionally, the initial position adjustment command can instruct the control rods to be adjusted from their initial position within the core to the core top. The initial position adjustment command can include the adjustment magnitude and direction.

[0063] The initial position of the control rods in the core can be understood as the position at which the control rods are initially inserted into the core.

[0064] S120. When the reactivity of the reactor is stable, obtain the value of the initial reactivity.

[0065] Specifically, stable reactor reactivity can be understood as the reactor operating state being in equilibrium. When the reactor reactivity is stable, the data acquisition device can collect the current reactor reactivity value, i.e., the initial reactivity value, and send the initial reactivity value to the digital experimental simulation device.

[0066] Furthermore, if Figure 4 As shown, the step of obtaining the terminal reactivity value of the reactor when the control rod is adjusted from the inside of the core to the bottom of the core in the above S200 can be achieved by the following steps:

[0067] S210, controlling and adjusting the control rods from the initial position in the core to the bottom of the core.

[0068] Specifically, the digital experimental simulation device can send a final position adjustment command to the control rod drive system (CRDS) where control rods are inserted, instructing the CRDS to adjust any bundle of control rods inserted into the reactor core from their final position within the core to the core bottom. Optionally, the final position adjustment command can instruct the control rods to be adjusted from their initial position within the core to the core bottom. The final position adjustment command can include the adjustment magnitude and direction.

[0069] In the process of adjusting the position of any bundle of control rods in the core, the reactivity of the reactor may undergo different changes or the same changes.

[0070] S220. When the reactivity of the reactor is stable, obtain the value of the final reactivity.

[0071] It is understandable that when the reactivity of the reactor is stable, the data acquisition device can collect the current reactivity value corresponding to the current control rod, that is, the value of the final reactivity, and can send the value of the final reactivity to the digital experimental simulation device.

[0072] Optionally, the parameters in the initial reactivity have a one-to-one correspondence with the parameters in the final reactivity; for example, the parameter A in the initial reactivity, when the control rod is adjusted from the initial position in the core to the bottom of the core, has the parameter A1 of the final reactivity when the reactivity of the reactor is stable.

[0073] The above-mentioned nuclear power plant power distribution measurement method can control the control rods to be adjusted to different positions in the core of the reactor, and obtain the reactivity corresponding to different positions, so as to obtain the radial power distribution of the core based on the reactivity value and the theoretical power of the control rod assembly corresponding to the control rod; this method is not only applicable to the power distribution measurement of the core of first- and second-generation nuclear power units, but also to the power distribution measurement of the core of third-generation nuclear power units, thereby making the power distribution measurement method highly reliable and more applicable; at the same time, compared with traditional technologies, the above-mentioned method can realize the power distribution measurement of the core in a zero-power physical test platform, thereby improving the accuracy of power distribution measurement in the zero-power physical test platform.

[0074] As one of the embodiments, the core includes multiple control rod assemblies; after obtaining the initial reactivity value and the final reactivity value of the current control rod, the above method also includes: controlling the current control rod to be adjusted from the bottom of the core to the top of the core, and for each other control rod, continuing to perform the step of obtaining the initial reactivity value of the reactor when adjusting the control rod from the inside of the reactor core to the top of the core, until the initial reactivity value and the final reactivity value of all control rods are obtained, so as to obtain the radial power distribution of the core through the initial reactivity value and the final reactivity value of all control rods and the theoretical power of the control rod assemblies corresponding to all control rods.

[0075] It is understood that there are multiple bundles of control rods inserted into the reactor core. For each bundle of control rods, the steps in S100 and S200 can be performed until the initial reactivity value and the final reactivity value corresponding to each bundle of control rods are obtained. Furthermore, the radial power distribution of the entire core can be obtained using the obtained initial reactivity value and the final reactivity value corresponding to each bundle of control rods and the theoretical power of the control rod assembly corresponding to each bundle of control rods.

[0076] It should be noted that the digital experimental simulation device can send initial position adjustment instructions to the control rod drive system where control rods are inserted, thereby controlling the synchronous adjustment of all control rods from their initial positions within the core to the top of the core. It can also send final position adjustment instructions to the control rod drive system where control rods are inserted, thereby controlling the asynchronous adjustment of all control rods from their initial positions within the core to the top of the core. Simultaneously, the digital experimental simulation device can control the asynchronous adjustment of each control rod within the core from its initial position within the core to the bottom of the core. That is, the digital experimental simulation device can first control the asynchronous adjustment of one bundle of control rods from its initial position within the core to the bottom of the core, and then control the asynchronous adjustment of another bundle of control rods from its initial position within the core to the bottom of the core, until all control rods are asynchronously adjusted from their initial positions within the core to the bottom of the core.

[0077] However, in this embodiment, when controlling the adjustment of each control rod within the core from its initial position to the core bottom, the initial reaction state of the reactor is the same. That is, different control rods within the core can be controlled to adjust from their initial position to the core bottom under the same reaction state. During each simulation, only the position of one bundle of control rods within the core is controlled, while the positions of the other control rods remain at the core top. In this embodiment, a single simulation can be performed for each bundle of control rods. In this embodiment, the control rods can be inserted from their initial position within the core to the core bottom using a step-by-step control method, or directly dropped from their initial position to the core bottom using a rod drop method.

[0078] The above-mentioned nuclear power plant power distribution measurement method can control the adjustment of all control rods to different positions within the reactor core and obtain the reactivity corresponding to different positions. Then, based on the reactivity values ​​of all control rods at different positions and the theoretical power of the control rod assemblies corresponding to all control rods, the radial power distribution of the core is obtained, further improving the accuracy of power distribution measurement in the zero-power physical test platform; in addition, the above-mentioned method can also measure the single-rod value of all control rod bundles, which is used to analyze parameter exceeding the standard such as the single-rod value exceeding the standard during the reactor zero-power physical test, and further verify the consistency of the core design so that the measured power distribution is consistent with the theoretical power distribution.

[0079] As one example, Figure 5 As shown, the step of obtaining the radial power distribution of the core by using the initial reactivity value, the final reactivity value, and the theoretical power of the control rod assembly corresponding to the control rod in S300 includes:

[0080] S310. Determine the single-rod measurement value of each control rod based on the initial reactivity value and the final reactivity value of each control rod.

[0081] Specifically, the digital experimental simulation device can perform arithmetic operations, comparison processing, numerical conversion processing, and / or normalization processing on the obtained initial reactivity values ​​and final reactivity values ​​of each control rod to obtain the single-rod measurement value of each control rod in the core. However, in this embodiment, the digital experimental simulation device can perform a subtraction operation on the obtained initial reactivity values ​​and final reactivity values ​​of each control rod to obtain the single-rod measurement value of each control rod. For example, if the initial reactivity value of a bundle of control rods T is ρ T1 The final reactivity of the control rod T is ρ T2 , then the single rod measurement value of the bundle of control rods ρ T测 =ρ T1 -ρ T2 .

[0082] The single-rod measurement value of the control rod can be used to measure the degree of deviation between the reactivity of the reactor when the control rod is adjusted from the initial position to different positions.

[0083] S320. Determine the value coefficient of each control rod based on the single-rod measured value and the single-rod theoretical value of each control rod.

[0084] It is understood that the digital experimental simulation device can perform an arithmetic operation on the measured value of each control rod and the theoretical value of each control rod to obtain the value coefficient of each control rod. The arithmetic operation can be addition, subtraction, division, multiplication, exponential operation, logarithmic operation, or a combination of these operations.

[0085] Among them, the step of determining the value coefficient of each control rod based on the single-rod measured value and the single-rod theoretical value of each control rod in the above S320 may specifically include: taking the square root of the quotient of the single-rod measured value of each control rod and the single-rod theoretical value of each control rod to obtain the value coefficient of each control rod.

[0086] In this embodiment, the digital experimental simulation device can first calculate the quotient of the measured value of each control rod and the theoretical value of each control rod, and then take the square root of the quotient to obtain the value coefficient of each bundle of control rods. Continuing with the previous example, if the theoretical value of the control rod of the bundle is ρ T理 , then the value coefficient of the control rod bundle is

[0087] S330. Multiply the theoretical power of the control rod assembly corresponding to each control rod by the value coefficient to determine the measured power of the control rod assembly corresponding to each control rod.

[0088] Specifically, the digital experimental simulation device can calculate the product of the theoretical power of the control rod assembly corresponding to each control rod and the value coefficient corresponding to each control rod to obtain the measured power of the control rod assembly corresponding to each control rod. In this embodiment, the reactor core includes a nuclear fuel assembly, which can be a control rod assembly and a non-control rod assembly. A control rod assembly can be understood as a nuclear fuel assembly with control rods, and a non-control rod assembly can be understood as a nuclear fuel assembly without control rods.

[0089] S340. Preprocess the measured powers of the control rod assemblies corresponding to all control rods to obtain the radial power distribution of the core.

[0090] Specifically, the above-mentioned preprocessing may include arithmetic operations, comparison processing, and / or numerical conversion processing, etc. The digital experimental simulation device may perform arithmetic operations, comparison processing, and / or numerical conversion processing, etc. on the measured powers of the control rod assemblies corresponding to all control rods to obtain the radial power distribution of the core. Alternatively, the digital experimental simulation device may perform arithmetic operations, comparison processing, and / or numerical conversion processing, etc. on the measured powers of the control rod assemblies corresponding to all control rods to obtain the radial power distribution of the core. Of course, the digital experimental simulation device may also perform arithmetic operations, comparison processing, and / or numerical conversion processing, etc. on the measured powers of the control rod assemblies corresponding to all control rods and a preset power threshold to obtain the radial power distribution of the core.

[0091] The above-mentioned nuclear power plant power distribution measurement method can obtain the radial power distribution of the core; this method is not only applicable to the power distribution measurement of the core of first- and second-generation nuclear power units, but also to the power distribution measurement of the core of third-generation nuclear power units, thereby making the power distribution measurement method highly reliable and more applicable; at the same time, compared with traditional technologies, the above-mentioned method can realize the power distribution measurement of the core in a zero-power physical test platform, thereby improving the accuracy of power distribution measurement in the zero-power physical test platform.

[0092] As one example, Figure 6 As shown, the step of pre-processing the measured powers of the control rod assemblies corresponding to all control rods in S340 to obtain the radial power distribution of the core can be achieved by the following steps:

[0093] S341. Fit the measured power of non-control rod assemblies by the measured power of all control rod assemblies.

[0094] Specifically, the digital experimental simulation device can use a polynomial fitting method to fit the measured powers of non-control rod assemblies based on the measured powers of all control rod assemblies. The polynomial fitting method can be a polynomial curve fitting method, a least squares fitting method, etc. However, in this embodiment, the polynomial fitting method is a spline fitting method.

[0095] S342. Normalize the measured powers of all control rod assemblies and the measured powers of all non-control rod assemblies to obtain the radial power distribution of the core.

[0096] Specifically, the reactor core can approximate a cylindrical structure, with the radial direction along the radius of the cylindrical structure being the radial direction and the axial direction along the side of the cylindrical structure being the axial direction. The radial power distribution of the core can be understood as a radial power distribution structure diagram, which can include the radial power of the control rod assembly and the radial power of the non-control rod assembly. The radial power distribution structure diagram can include multiple square power distribution structure diagrams, each of which represents the radial power of a control rod assembly or the radial power of a non-control rod assembly. The total number of square power distribution structure diagrams in the radial power distribution structure diagram can be equal to the total number of control rod assemblies and non-control rod assemblies in the core.

[0097] Optionally, the radial power of the control rod assembly can be the result of normalizing the measured powers of the control rod assemblies and non-control rod assemblies in all fuel assemblies. Optionally, the normalization process can be understood as the process of normalizing the measured powers of the control rod assemblies and non-control rod assemblies in all fuel assemblies to a value between 0 and 1. However, in this embodiment, the normalization process can be understood as the process of dividing the measured powers of each control rod assembly and each non-control rod assembly in all fuel assemblies by the average of the measured powers of all control rod assemblies and non-control rod assemblies in all fuel assemblies, where the average of the measured powers of all control rod assemblies and non-control rod assemblies in all fuel assemblies is equal to 1. The sum of all the results obtained from the normalization process can be equal to the total number of all control rod assemblies and non-control rod assemblies in all fuel assemblies.

[0098] The above-mentioned nuclear power plant power distribution measurement method can be combined with the single rod theoretical value to obtain the radial power distribution of the core, thereby improving the accuracy of power distribution measurement in the zero-power physical test platform, so that the measured power distribution is consistent with the theoretical power distribution, and avoiding the single rod value exceeding the standard during the zero-power physical test.

[0099] Another embodiment provides a schematic structural diagram of a nuclear power plant power distribution measurement system; the nuclear power plant power distribution measurement system includes: a data acquisition device and a digital experimental simulation device;

[0100] A data acquisition device is used to collect the initial reactivity value and the final reactivity value of the reactor and send them to the digital experimental simulation device;

[0101] Digital experimental simulation equipment for performing the above Figure 2-6 The method steps of any embodiment.

[0102] In this embodiment, the aforementioned data acquisition device may be a sensor, a nuclear measurement system, a detector, or other equipment. In this embodiment, after the digital experimental simulation device in the nuclear power plant power distribution measurement system controls the control rods to be adjusted from their initial position within the core to the top of the core, the data acquisition device can collect the initial reactivity value of the reactor. Simultaneously, after the digital experimental simulation device in the nuclear power plant power distribution measurement system controls the control rods to be adjusted from their initial position within the core to the bottom of the core, the data acquisition device can collect the final reactivity value of the reactor.

[0103] It is understood that the data acquisition device can send the collected initial reactivity value and final reactivity value of the reactor to the digital experimental simulation device, and then the experimental simulation device can perform the above-mentioned Figure 2-6 The method steps of any embodiment.

[0104] Furthermore, the above-mentioned nuclear power plant power distribution measurement system further comprises: a control rod drive system;

[0105] The control rod drive system is used to control the control rods to be adjusted from the core of the reactor to the top or bottom of the core, so that the data acquisition equipment can collect the initial reactivity value and the final reactivity value of the reactor.

[0106] Specifically, the control rod drive system may include a controller and a reactor pressure vessel, wherein the reactor pressure vessel may be used to insert a control rod assembly and a non-control rod assembly. The controller in the control rod drive system may receive initial position adjustment instructions and final position adjustment instructions sent by a digital experimental simulation device. Further, upon receiving the initial position adjustment instructions and the final position adjustment instructions, the controller controls the control rods in the control rod assembly to be adjusted from within the reactor core to the top or bottom of the core, respectively, so that the data acquisition device can collect initial and final reactivity values ​​of the reactor.

[0107] It should be noted that the reactor core can be pre-inserted into the reactor pressure vessel, and the core includes at least two bundles of control rods. Initially, the control rods can be inserted at any location within the core, regardless of location, as long as they are within the core. The controller in the control rod drive system can synchronously or asynchronously control and adjust the position of one or more control rods at the same or different locations within the reactor core, thereby varying the reactor's reactivity. In other words, inserting control rods throughout or partially within the core can alter the reactor's reactivity.

[0108] The controller in the CRDS can also synchronously or asynchronously adjust one or more control rods at the same or different locations within the reactor core to the bottom of the core. For the same control rod, the controller in the CRDS can control the adjustment of the same control rod from the same location to either the top or bottom of the core.

[0109] The above-mentioned nuclear power plant power distribution measurement system can obtain the value of the initial reactivity of the reactor when the control rod is adjusted from the core of the reactor to the top of the core, and obtain the value of the final reactivity of the reactor when the control rod is adjusted from the core to the bottom of the core, and obtain the radial power distribution of the core through the value of the initial reactivity, the value of the final reactivity and the theoretical power of the control rod assembly corresponding to the control rod; the system is not only applicable to the power distribution measurement of the core of the first and second generation nuclear power units, but also to the power distribution measurement of the core of the third generation nuclear power units, thereby making the power distribution measurement method more reliable and more applicable; at the same time, compared with traditional technologies, the above-mentioned system can realize the power distribution measurement of the core in the zero-power physical test platform, thereby improving the accuracy of the power distribution measurement in the zero-power physical test platform, so that the measured power distribution is consistent with the theoretical power distribution, and avoiding the single rod value exceeding the standard during the zero-power physical test.

[0110] To facilitate understanding by those skilled in the art, the nuclear power plant power distribution measurement method provided by this application is described by taking a digital experimental simulation device as an example. Specifically, the method includes:

[0111] (1) Obtain the value of the initial reactivity of the reactor when each control rod in the core is adjusted from the core to the top of the reactor core.

[0112] (2) Obtain the terminal reactivity value of the reactor when each control rod in the core is adjusted from the core to the bottom of the core.

[0113] (3) The single-rod measurement value of each control rod is determined by the initial reactivity value and the final reactivity value of each control rod.

[0114] (4) The square root of the quotient of the single-rod measured value of each control rod and the single-rod theoretical value of each control rod is taken to obtain the value coefficient of each control rod.

[0115] (5) The product of the theoretical power of the control rod assembly corresponding to each control rod and the value coefficient is determined as the measured power of the control rod assembly corresponding to each control rod.

[0116] (6) Fit the measured power of the non-control rod assembly by the measured power of all control rod assemblies.

[0117] (7) The measured powers of all control rod assemblies and all non-control rod assemblies are normalized to obtain the radial power distribution of the core.

[0118] The execution process of the above (1) to (7) can be specifically referred to the description of the above embodiment. The implementation principles and technical effects are similar and will not be repeated here.

[0119] It should be understood that although Figure 2-6 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. In addition, Figure 2-6 At least part of the steps may include multiple steps or multiple stages. These steps or stages are not necessarily performed at the same time, but can be performed at different times. The order of execution of these steps or stages is not necessarily one by one, but can be performed in turn or alternately with other steps or at least part of the steps or stages in other steps.

[0120] In one embodiment, Figure 7 As shown, a nuclear power plant power distribution measurement device is provided, comprising: an initial reactivity acquisition module 11, a final value reactivity acquisition module 12 and a power acquisition module 13, wherein:

[0121] An initial reactivity acquisition module 11 is used to obtain a value of the initial reactivity of the reactor when the control rod is adjusted from the reactor core to the top of the reactor core;

[0122] The terminal reactivity acquisition module 12 is used to obtain the terminal reactivity value of the reactor when the control rod is adjusted from the inside of the core to the bottom of the core;

[0123] The power acquisition module 13 is used to obtain the radial power distribution of the core through the value of the initial reactivity, the value of the final reactivity and the theoretical power of the control rod assembly corresponding to the control rod.

[0124] The nuclear power plant power distribution measurement device provided in this embodiment can execute the above method embodiment. Its implementation principles and technical effects are similar and will not be repeated here.

[0125] In one embodiment, the initial reactivity acquisition module 11 includes: a first position control unit and an initial value acquisition unit, wherein:

[0126] a first position control unit for controlling the adjustment of the control rods from an initial position in the reactor core to a core top of the reactor core;

[0127] The initial value acquisition unit is used to acquire the value of the initial reactivity when the reactivity of the reactor is stable.

[0128] The nuclear power plant power distribution measurement device provided in this embodiment can execute the above method embodiment. Its implementation principles and technical effects are similar and will not be repeated here.

[0129] In one embodiment, the final value reactivity acquisition module 12 includes: a second position control unit and a final value acquisition unit, wherein:

[0130] a second position control unit for adjusting the control rods from an initial position within the core to the bottom of the core;

[0131] The final value obtaining unit is used to obtain the value of the final value reactivity when the reactivity of the reactor is stable.

[0132] The nuclear power plant power distribution measurement device provided in this embodiment can execute the above method embodiment. Its implementation principles and technical effects are similar and will not be repeated here.

[0133] In one embodiment, a reactor core includes a plurality of control rod assemblies; the nuclear power plant power distribution measurement device further includes: an end position control unit and a position control cycle unit, wherein:

[0134] an end position control unit, used for controlling the adjustment of the current control rod from the bottom of the core to the top of the core;

[0135] The position control loop unit is configured to continue executing the step of obtaining the initial reactivity value of the reactor for each of the other control rods when the control rod is adjusted from within the reactor core to the top of the reactor core, until the initial reactivity values ​​and final reactivity values ​​of all the control rods are obtained, so as to obtain the radial power distribution of the core based on the initial reactivity values ​​and final reactivity values ​​of all the control rods and the theoretical powers of the control rod assemblies corresponding to all the control rods.

[0136] The nuclear power plant power distribution measurement device provided in this embodiment can execute the above method embodiment. Its implementation principles and technical effects are similar and will not be repeated here.

[0137] In one embodiment, the power acquisition module 13 includes: a measurement value acquisition unit, a value coefficient acquisition unit, a measurement power acquisition unit, and a radial power distribution acquisition unit, wherein:

[0138] a measurement value obtaining unit, configured to determine a single-rod measurement value of each control rod according to an initial reactivity value and a final reactivity value of each control rod;

[0139] a value coefficient obtaining unit, configured to determine a value coefficient of each control rod based on a single-rod measured value and a single-rod theoretical value of each control rod;

[0140] a measured power acquisition unit, configured to determine the measured power of the control rod assembly corresponding to each control rod by multiplying the theoretical power of the control rod assembly corresponding to each control rod by a value coefficient;

[0141] The radial power distribution acquisition unit is used to obtain the radial power distribution of the core by preprocessing the measured power of the control rod assemblies corresponding to all control rods.

[0142] The nuclear power plant power distribution measurement device provided in this embodiment can execute the above method embodiment. Its implementation principles and technical effects are similar and will not be repeated here.

[0143] In one embodiment, the value coefficient obtaining unit is specifically configured to obtain the value coefficient of each control rod by taking the square root of the quotient of the single-rod measured value of each control rod and the single-rod theoretical value of each control rod.

[0144] The nuclear power plant power distribution measurement device provided in this embodiment can execute the above method embodiment. Its implementation principles and technical effects are similar and will not be repeated here.

[0145] In one embodiment, the reactor core includes a control rod assembly and a non-control rod assembly; the radial power distribution acquisition unit includes: a measured power acquisition subunit and a normalization processing subunit, wherein:

[0146] a measured power acquisition subunit, configured to fit the measured power of the non-control rod assembly through the measured power of all control rod assemblies;

[0147] The normalization processing subunit is used to normalize the measured powers of all control rod assemblies and all non-control rod assemblies to obtain the radial power distribution of the core.

[0148] The nuclear power plant power distribution measurement device provided in this embodiment can execute the above method embodiment. Its implementation principles and technical effects are similar and will not be repeated here.

[0149] The specific limitations of the nuclear power plant power distribution measurement device can be found in the limitations of the nuclear power plant power distribution measurement method described above and will not be repeated here. Each module in the above-mentioned power distribution measurement device can be implemented in whole or in part through software, hardware, or a combination thereof. Each of the above-mentioned modules can be embedded in or independent of the processor in the digital experimental simulation device in hardware form, or can be stored in the memory of the digital experimental simulation device in software form, so that the processor can call and execute the corresponding operations of each of the above modules.

[0150] In one embodiment, a digital experiment simulation device is provided, comprising a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the following steps are implemented:

[0151] obtaining a value of the initial reactivity of the reactor when the control rod is adjusted from within the core of the reactor to the top of the core;

[0152] Obtaining the terminal reactivity value of the reactor when the control rod is adjusted from inside the core to the bottom of the core;

[0153] The radial power distribution of the core is obtained by the value of the initial reactivity, the value of the final reactivity and the theoretical power of the control rod assembly corresponding to the control rod.

[0154] In one embodiment, a readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the following steps are implemented:

[0155] obtaining a value of the initial reactivity of the reactor when the control rod is adjusted from within the core of the reactor to the top of the core;

[0156] Obtaining the terminal reactivity value of the reactor when the control rod is adjusted from inside the core to the bottom of the core;

[0157] The radial power distribution of the core is obtained by the value of the initial reactivity, the value of the final reactivity and the theoretical power of the control rod assembly corresponding to the control rod.

[0158] In one embodiment, a computer program product is provided, comprising a computer program, which, when executed by a processor, implements the following steps:

[0159] obtaining a value of the initial reactivity of the reactor when the control rod is adjusted from within the core of the reactor to the top of the core;

[0160] Obtaining the terminal reactivity value of the reactor when the control rod is adjusted from inside the core to the bottom of the core;

[0161] The radial power distribution of the core is obtained by the value of the initial reactivity, the value of the final reactivity and the theoretical power of the control rod assembly corresponding to the control rod.

[0162] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0163] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0164] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art could make various modifications and improvements without departing from the spirit of the present application, all of which fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A method for measuring power distribution in a nuclear power plant, characterized in that: A digital experimental simulation device used to simulate a nuclear power unit in a zero-power physical test platform, the method comprising: obtaining a value of the initial reactivity of the reactor when each control rod in the reactor core is adjusted from the reactor core to the top of the reactor core; obtaining a terminal reactivity value of the reactor when each of the control rods in the core is adjusted from the core to the bottom of the core; performing a subtraction operation on the initial reactivity value and the final reactivity value of each of the control rods to determine a single-rod measurement value of each of the control rods; The value coefficient of each control rod is obtained by dividing the single-rod measured value of each control rod by the single-rod theoretical value of each control rod and taking the square root thereof; multiplying the theoretical power of the control rod assembly corresponding to each of the control rods by a value coefficient to determine the measured power of the control rod assembly corresponding to each of the control rods; Fitting the measured power of non-control rod assemblies by the measured power of all control rod assemblies; Normalizing the measured powers of all control rod assemblies and the measured powers of all non-control rod assemblies to obtain the radial power distribution of the core.

2. The method according to claim 1, characterized in that The obtaining of the initial reactivity value of the reactor when each control rod in the reactor core is adjusted from the reactor core to the top of the reactor core includes: For any one control rod, controlling the control rod to be adjusted from an initial position in the reactor core to a core top of the reactor core; When the reactivity of the reactor is stable, the value of the initial reactivity is obtained.

3. The method according to claim 1 or 2, characterized in that The obtaining of the terminal reactivity value of the reactor when each of the control rods in the core is adjusted from the core to the bottom of the core includes: For any one control rod, controlling the control rod to be adjusted from an initial position in the core to a bottom of the core; When the reactivity of the reactor is stable, the value of the final reactivity is obtained.

4. The method according to claim 1 or 2, characterized in that The reactor comprises at least a core, a structure, control rods and a shield.

5. The method according to claim 1, wherein The single-rod measurement value is used to measure the degree of deviation between the reactivity of the reactor when the control rod is adjusted from an initial position to different positions.

6. The method according to claim 1 or 2, characterized in that The reactivity characterizes the extent to which the reactor deviates from criticality.

7. The method according to claim 1 or 2, characterized in that The fitting of the measured powers of the non-control rod assemblies by the measured powers of all control rod assemblies includes: The measured powers of the non-control rod assemblies are fitted using a polynomial fitting method according to the measured powers of all the control rod assemblies.

8. A power distribution measurement device for a nuclear power plant, characterized in that: The device comprises: an initial reactivity acquisition module, configured to acquire a value of the initial reactivity of the reactor when each control rod in the reactor core is adjusted from the reactor core to the top of the reactor core; a terminal reactivity acquisition module, configured to acquire a terminal reactivity value of the reactor when each of the control rods in the core is adjusted from the core to the bottom of the core; The power acquisition module is configured to perform a subtraction operation on the initial reactivity value and the final reactivity value of each control rod to determine the single-rod measurement value of each control rod; obtain the value coefficient of each control rod by taking the square root of the quotient of the single-rod measurement value of each control rod and the single-rod theoretical value of each control rod; determine the measured power of the control rod assembly corresponding to each control rod by multiplying the theoretical power of the control rod assembly corresponding to each control rod by the value coefficient; fit the measured power of non-control rod assemblies using the measured power of all control rod assemblies; and normalize the measured power of all control rod assemblies and the measured power of all non-control rod assemblies to obtain the radial power distribution of the core.

9. A nuclear power plant power distribution measurement system, characterized in that: The system includes: data acquisition equipment and digital experiment simulation equipment; The data acquisition device is used to collect the initial reactivity value and the final reactivity value of the reactor and send them to the digital experimental simulation device; The digital experimental simulation device is used to perform the steps in the method described in any one of claims 1 to 7.

10. The system according to claim 9, characterized in that The system further includes: a control rod drive system; The control rod drive system is used to control the adjustment of each control rod from the core of the reactor to the top or bottom of the core, so that the data acquisition equipment can collect the initial reactivity value and the final reactivity value of the reactor.

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