A method for evaluating the pre-movement of a containment pressure relief vent activity monitor (MCA)

Abstract

The application discloses a method for evaluating the front movement of a containment pressure relief exhaust activity monitor MCA, and relates to the technical field of radiation monitoring of nuclear power plants. The evaluation method comprises the following steps: 1) obtaining a layout design file of an active electronic component of the containment pressure relief exhaust activity monitor MCA; 2) constructing a basic unit array corresponding to each layer of the layout design file; 3) determining a target unit; 4) extracting incident particle information, constructing a Monte Carlo simulation model and performing Monte Carlo simulation simulation; 5) obtaining a logic value of each layer of the target unit of each active electronic component; and 6) evaluating whether the containment pressure relief exhaust activity monitor MCA is moved forward. According to the method, the active electronic component of the containment pressure relief exhaust activity monitor MCA is disassembled into basic units that are completely matched with an actual layout design, radiation simulation is performed on each layer of the target unit related to the design, and refined modeling is realized from the whole to the part and from the design to the unit, so that the evaluation result is more referable.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of radiation monitoring of nuclear power plants, and particularly relates to a method for evaluating forward movement of a containment pressure relief vent activity monitor MCA. BACKGROUND

[0002] The containment pressure relief vent activity monitor is a special monitoring device under severe accident conditions of a nuclear power plant. When a severe accident such as reactor core melting occurs in the nuclear power plant, the pressure in the containment vessel increases sharply, and in order to avoid rupture of the containment vessel due to excessive pressure, a pressure relief operation needs to be performed to discharge the gas in the containment vessel. During the gas discharge process, the radioactivity in the gas needs to be monitored in real time.

[0003] The containment pressure relief vent activity monitor mainly reflects the radioactivity leakage by monitoring the intensity of γ rays in the exhaust duct. Generally, the signal detection and processing part of the containment pressure relief vent activity monitor mainly consists of a detector unit, a photomultiplier tube, a front-end amplifier, a main amplifier, a multichannel pulse amplitude analyzer (referred to as a multichannel analyzer, abbreviated as MCA), a data display processing unit, etc. Among these main components, the detector unit, the photomultiplier tube, and the front-end amplifier are generally designed in one component and are mainly placed in a lead shielding body to realize real-time monitoring of the γ ray concentration activity in the exhaust pipe. The main amplifier, the multichannel pulse amplitude analyzer, and the high-voltage module are generally integrated in one component and are arranged together with the data display processing component in an operable area tens of meters away from the detector component. The detector component and the multichannel pulse amplitude analyzer component are connected and communicate through tens of meters of shielded wires.

[0004] The traditional connection mode of the detector component and the multichannel pulse amplitude analyzer component through tens of meters of shielded wires has non-negligible drawbacks. Specifically, because the transmitted signal is an analog signal, the tens of meters of transmission lines will cause undesirable signal changes due to cable capacitance effects, etc. For example, signal attenuation and distortion, pulse amplitude distortion, and signal-to-noise ratio reduction. If the multichannel pulse amplitude analyzer component is moved forward to the vicinity of the detector component, such as also being arranged in the lead shielding body, and the connection and communication of the detector signal and the data display processing unit are realized through digital signal transmission, the signal attenuation and distortion can be better avoided.

[0005] However, when the multichannel pulse amplitude analyzer assembly is moved forward, the device will be affected by the total dose effect of gamma irradiation, which will affect its normal working performance, and even cause the device to completely fail due to the total dose effect. This is unacceptable for the radiation monitoring system of a nuclear power plant. Therefore, when the multichannel pulse amplitude analyzer assembly is moved forward, its performance under gamma irradiation, whether it can work normally, and whether the influence of the total dose effect during work is acceptable are all problems that need to be judged and evaluated first. Currently, there is no detailed operation specification or rule to refer to for the radiation risk assessment of whether the multichannel pulse amplitude analyzer assembly of the containment pressure relief activity monitor can be moved forward. Therefore, when considering whether the multichannel pulse amplitude analyzer assembly of the containment pressure relief activity monitor can be moved forward, a feasible evaluation method must be proposed. SUMMARY

[0006] The technical problem to be solved by the present application is to provide a containment pressure relief exhaust activity monitor MCA forward movement evaluation method to solve the above technical problems in the prior art.

[0007] To solve the above technical problems, the technical solution adopted by the present application is: a containment pressure relief exhaust activity monitor MCA forward movement evaluation method, characterized in that the method comprises the following steps:

[0008] Step one, obtain the layout design file of the active electronic components of the containment pressure relief exhaust activity monitor MCA: extract the layout design file of each layer of the active electronic components in the containment pressure relief exhaust activity monitor MCA, and the layout design file of each layer includes the minimum line width and size of all non-metal design lines of the circuit in this layer, the thickness and material information of the layout in this layer;

[0009] Step two, construct the basic unit array corresponding to each layer of layout design file: take the minimum line width of all non-metal design lines of the circuit in this layer as the length and width, take the thickness of the layout in this layer as the height, and combine the material information in this layer to construct the basic unit in this layer, and at the same time construct the basic unit array corresponding to the layout design file in this layer; the construction method of the basic unit array corresponding to each layer of layout design file is the same;

[0010] Step three, determine the target unit: overlap each layer of layout design file and the corresponding basic unit array, when there is a non-metal line overlap in the basic unit in this layer, the basic unit is the target unit, at the same time, mark the target unit as 1, otherwise, the basic unit is a non-target unit, mark the non-target unit as 0;

[0011] Step four, extracting incident particle information, constructing a Monte Carlo simulation model and performing Monte Carlo simulation: a Monte Carlo simulation model of each active electronic component of the containment pressure relief vent activity monitor MCA is constructed by using the basic cell array of all layers to perform Monte Carlo simulation, and the incident particle source flux and energy are obtained, and the deposited energy and total dose of each layer target cell are recorded;

[0012] Step five, obtaining the logic value of each active electronic component of each layer target cell: obtaining the maximum simulated cumulative dose of each active electronic component of each layer target cell, and comparing the maximum simulated cumulative dose of each active electronic component of each layer target cell with the maximum cumulative dose of each active electronic component of each layer target cell under actual working conditions;

[0013] If the maximum simulated cumulative dose of the active electronic component of the target cell in the layer is less than the maximum cumulative dose of the active electronic component of the target cell in the layer under actual working conditions, the logic value of the active electronic component of the target cell in the layer is 1, otherwise, the logic value of the active electronic component of the target cell in the layer is 0;

[0014] Step six, evaluating whether the containment pressure relief vent activity monitor MCA is moved forward: setting a two-stage AND gate structure, wherein one level AND gate is set for each active electronic component, and the logic value of each active electronic component of each layer target cell is input into the respective one-level AND gate, and each one-level AND gate outputs one one-level logic output value;

[0015] A two-stage AND gate is set, each one-level logic output value is input into the two-stage AND gate, and the two-stage AND gate outputs a two-stage logic output value, when the two-stage logic output value is 1, the containment pressure relief vent activity monitor MCA is moved forward; when the two-stage logic output value is 0, the containment pressure relief vent activity monitor MCA cannot be moved forward.

[0016] The above-mentioned method for evaluating whether the containment pressure relief vent activity monitor MCA is moved forward, characterized in that: the active electronic component includes an electron tube, a transistor and an integrated circuit.

[0017] The above-mentioned method for evaluating whether the containment pressure relief vent activity monitor MCA is moved forward, characterized in that: the basic cell is a cubic structure established according to the minimum line width of non-metal lines and the thickness of each layer of the layout design file.

[0018] The method for evaluating the MCA of the containment pressure relief exhaust activity monitor, characterized in that: in step two, the process of constructing the basic unit array corresponding to the layer layout design file is that the minimum line width of all non-metal design lines of the circuit in the layer is taken as the length and width, the thickness of the layout in the layer is taken as the height, the basic unit in the layer is constructed, the upper left corner is taken as the reference point, the whole layer is covered, and each basic unit is numbered one by one, and the basic unit array number (m, n) covered by the layout is extracted, wherein m represents the row number of the basic unit, and n represents the column number of the basic unit.

[0019] The method for evaluating the MCA of the containment pressure relief exhaust activity monitor, characterized in that: in step three, each layer layout design file and the corresponding basic unit array are overlapped; the overlapping operation process is that all basic units in each layer are overlapped with the plane layout of the layout design file in the layer, the basic units corresponding to the overlapping part of the non-metal design lines in the layout design file in the layer are marked as 1, and the marking determination rule is that unless a basic unit does not overlap with any non-metal line in the layout design file in the layer, it is determined that there is an overlapping part, and then the number corresponding to the basic unit is marked as 1, and the basic unit is the target unit.

[0020] The method has the following beneficial effects: the evaluation of whether the MCA of the containment pressure relief exhaust activity monitor moves forward is divided in detail, the influence of the internal fine structure on the radiation energy deposition is avoided, and the evaluation result is obviously deviated from the actual radiation effect rule, the specific evaluation reference for whether the multichannel pulse amplitude analyzer can move forward is filled, the active electronic components of the containment pressure relief exhaust activity monitor MCA are disassembled into basic units completely matched with the actual layout design, radiation simulation is performed on each layer target unit related to the design, the modeling is refined from the whole to the local and from the design to the unit, the radiation risk of the multichannel pulse amplitude analyzer component of the containment pressure relief exhaust activity monitor when moving forward can be accurately evaluated, the evaluation result is more close to the actual scene and more referential.

[0021] The technical solutions of the present application will be further described in detail below with reference to the drawings and embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0022] Fig. 1 The method flow chart of the present application.

[0023] Fig. 2 The process effect diagram for constructing the basic unit array corresponding to each layer layout design file of the present application.

[0024] Fig. 3This is a logic diagram for evaluating whether the containment depressurization venting activity monitor (MCA) should be moved forward in this invention. Detailed Implementation

[0025] like Figs. 1-3 As shown, the present invention provides a method for advancing the assessment of the MCA (Mean Control Area) of a containment depressurization venting activity monitor, comprising the following steps:

[0026] Step 1: Obtain the layout design files of the active electronic components of the containment depressurization exhaust activity monitor (MCA): Extract the layout design files of each layer of the active electronic components of the containment depressurization exhaust activity monitor (MCA). Each layer layout design file includes the minimum line width and size of the non-metallic design lines of all circuit components in this layer, the layout thickness of this layer, and material information.

[0027] Step 2: Construct the basic cell array corresponding to each layer of the layout design file: Using the minimum line width of all non-metallic design lines of the circuits in this layer as the length and width, and the thickness of this layer as the height, and combining the material information of this layer, construct the basic cell of this layer, and at the same time construct the basic cell array corresponding to the layout design file of this layer; the construction method of the basic cell array corresponding to each layer of the layout design file is the same.

[0028] It should be noted that, as Fig. 2 As shown, the line widths of all non-metallic design lines in a certain layer, from largest to smallest, are w1, w2, and w3. w3 is the smallest line width of all non-metallic design lines in this layer. Using w3 as the length and width, and the thickness of this layer as the height, and combining the material information of this layer, the basic unit of this layer is constructed.

[0029] Step 3: Determine the target cell: Overlay each layer of layout design file with the corresponding basic cell array. If there is non-metallic line overlap in the basic cell of this layer, then the basic cell is the target cell and is marked as 1. Otherwise, the basic cell is a non-target cell and is marked as 0.

[0030] Step 4: Extract incident particle information, construct Monte Carlo simulation model and perform Monte Carlo simulation: The Monte Carlo simulation model of each active electronic component of the containment depressurization exhaust activity monitor (MCA) is composed of basic unit arrays of all layers. The incident particle source flux and energy are obtained, and the deposition energy and total dose of the target unit in each layer are recorded.

[0031] It should be noted that the Monte Carlo simulation can be carried out after the simulation model is built and the incident particle information is determined. During the simulation process, the energy deposition and total dose of each layer of target unit are recorded in real time. The energy deposition and total dose of each layer are saved as a document, which contains the source electronic component number, the layout file layer number, the target unit number, the acting particle information, the action process information, the energy deposition, and the cumulative total dose.

[0032] By comparing the cumulative total dose value of each layer of target unit, the maximum cumulative total dose target unit of each layer of each active electronic component can be determined.

[0033] Step five, obtaining the logic value of each layer of target unit of each active electronic component: obtaining the maximum simulated cumulative dose of each layer of target unit of each active electronic component, and comparing the maximum simulated cumulative dose of each layer of target unit of each active electronic component with the maximum cumulative dose of each layer of target unit of each active electronic component under real working conditions.

[0034] If the maximum simulated cumulative dose of the target unit of the active electronic component is less than the maximum cumulative dose of the target unit of the active electronic component under real working conditions, the logic value of the target unit of the active electronic component is 1, otherwise, the logic value of the target unit of the active electronic component is 0.

[0035] Step six, evaluating whether the containment pressure relief and exhaust activity monitor MCA is moved forward: setting a two-stage AND gate structure, wherein one level AND gate is set for each active electronic component, and the logic value of each layer of target unit of each active electronic component is input into the respective one level AND gate, and each one level AND gate outputs one one-level logic output value.

[0036] A two-stage AND gate is set, each one-level logic output value is input into the two-stage AND gate, and the two-stage AND gate outputs a two-stage logic output value. When the two-stage logic output value is 1, the containment pressure relief and exhaust activity monitor MCA is moved forward; when the two-stage logic output value is 0, the containment pressure relief and exhaust activity monitor MCA cannot be moved forward.

[0037] In this embodiment, the active electronic component includes an electronic tube, a transistor, and an integrated circuit.

[0038] In this embodiment, the basic unit is a cubic structure established according to the minimum line width of the non-metal design line of each layer of layout design file and the thickness of each layer.

[0039] In this embodiment, in step two, the process of constructing the basic cell array corresponding to the current layer layout design file is as follows: taking the minimum line width of all non-metal design lines in the current layer as the length and width, and taking the thickness of the current layer as the height, a basic cell is constructed, which is taken as the reference point, fills the whole layer, and is numbered one by one. Each basic cell is numbered according to its row and column position. The basic cell array number (m, n) covered by the layout is extracted, wherein m represents the row number of the basic cell, and n represents the column number of the basic cell. In actual operation, for example, in a certain layer layout, the minimum line width of the non-metal design line is a microns, and the thickness of the layer is b microns. The basic cell constructed is a cube with a length and a width of a microns and a thickness of b microns. The basic cells are numbered in the order from left to right and from top to bottom, for example, the cell number of the mth row and the nth column is (m, n).

[0040] In this embodiment, in step three, the layout design file of each layer and the corresponding basic cell array are overlapped. The overlapping operation process is as follows: all basic cells of each layer are overlapped with the planar layout of the layout design file of the layer. The basic cells corresponding to the overlapping part of the non-metal design line in the layout design file of the layer are marked as 1. The marking determination rule is that unless a basic cell does not overlap with any non-metal line in the layout design file of the layer, it is determined that there is an overlapping part. Then, the number corresponding to the basic cell is marked as 1. The basic cell is the target cell.

[0041] When the present application is implemented, the evaluation of whether the containment pressure relief and exhaust activity monitor MCA is moved forward by the radiation influence is detailed, the influence of the internal fine structure on the radiation energy deposition is avoided to be ignored, and obvious deviation between the evaluation result and the actual radiation effect rule is caused. The specific evaluation reference of whether the multichannel pulse amplitude analyzer can be moved forward is filled. By disassembling the active electronic components of the containment pressure relief and exhaust activity monitor MCA into basic cells completely matched with the actual layout design, and performing radiation simulation on each layer target cell related to the design, the refined modeling from the whole to the local and from the design to the cell is realized. The radiation risk of the multichannel pulse amplitude analyzer component of the containment pressure relief and exhaust activity monitor when the component is moved forward can be accurately evaluated. The evaluation result is more close to the actual scene and more referential.

[0042] The above is only a preferred embodiment of the present application, and does not limit the present application. Any simple modification, change and equivalent structure change made according to the technical essence of the present application to the above embodiment are still within the protection scope of the technical solution of the present application.

Claims

1. A method for evaluating the advance of a containment pressure relief vent monitor (MCA), characterized in that, The method comprises the following steps: Step one, obtaining the layout design file of the active electronic component of the containment pressure relief exhaust activity monitor MCA: extracting the layout design file of each layer of the active electronic component of the containment pressure relief exhaust activity monitor MCA, wherein the layout design file of each layer comprises the minimum line width and size of all non-metal design lines of the circuit in the layer, the thickness and material information of the layout in the layer; Step two, constructing the basic unit array corresponding to the layout design file of each layer: taking the minimum line width of all non-metal design lines of the circuit in the layer as the length and width, taking the thickness of the layout in the layer as the height, and combining the non-metal material information in the layer, a basic unit in the layer is constructed, and a basic unit array corresponding to the layout design file of the layer is also constructed; the construction method of the basic unit array corresponding to the layout design file of each layer is the same; Step three, determining the target unit: overlapping the layout design file of each layer and the corresponding basic unit array, when the basic unit in the layer has non-metal line overlap, the basic unit is the target unit, and the target unit is marked as 1, otherwise, the basic unit is a non-target unit, and the non-target unit is marked as 0; Step four, extracting the incident particle information, constructing the Monte Carlo simulation model and performing Monte Carlo simulation: performing Monte Carlo simulation on the Monte Carlo simulation model of each active electronic component of the containment pressure relief exhaust activity monitor MCA composed of the basic unit arrays of all layers to obtain the incident particle source flux and energy, and record the deposited energy and total dose of the target unit in each layer; Step five, obtaining the logic value of each target unit in each layer of each active electronic component: obtaining the maximum simulated cumulative dose of each target unit in each layer of each active electronic component, and comparing the maximum simulated cumulative dose of each target unit in each layer of each active electronic component with the maximum cumulative dose of each target unit in each layer of each active electronic component under the actual working condition; If the maximum simulated cumulative dose of the target unit in the layer of the active electronic component is smaller than the maximum cumulative dose of the target unit in the layer of the active electronic component under the actual working condition, the logic value of the target unit in the layer of the active electronic component is 1, otherwise, the logic value of the target unit in the layer of the active electronic component is 0; Step six, evaluating whether the containment pressure relief exhaust activity monitor MCA is moved forward: setting a two-stage AND gate structure, wherein each active electronic component is provided with a one-stage AND gate, and the logic value of each target unit in each layer of each active electronic component is input into the respective one-stage AND gate, and each one-stage AND gate outputs a one-stage logic output value; A two-stage AND gate is set, each one-stage logic output value is input into the two-stage AND gate, and the two-stage AND gate outputs a two-stage logic output value; when the two-stage logic output value is 1, the containment pressure relief exhaust activity monitor MCA is moved forward; when the two-stage logic output value is 0, the containment pressure relief exhaust activity monitor MCA cannot be moved forward.

2. The method for evaluating the MCA shift of the containment pressure relief vent MCA according to claim 1, characterized in that: The active electronic component comprises an electron tube, a transistor and an integrated circuit.

3. The method for MCA shift assessment of a containment pressure relief vent monitor MCA according to claim 1, characterized in that: The basic unit is a cubic structure established according to the minimum line width of the non-metal design line of each layer and the thickness of each layer.

4. The method for MCA shift assessment of a containment pressure relief vent monitor MCA according to claim 1, characterized in that: In step two, the process of constructing the basic cell array corresponding to the current layer layout design file is as follows: taking the minimum line width of all non-metal design lines of the circuit in the current layer as the length and width, and taking the thickness of the current layer layout as the height, the basic cell in the current layer is constructed, taking the upper left corner as the reference point, covering the whole layer, and being numbered one by one. Each basic cell is numbered according to its row and column position. The basic cell array number (m, n) covered by the layout is extracted, wherein m represents the row number of the basic cell, and n represents the column number of the basic cell.

5. The method for MCA shift assessment of a containment pressure relief vent activity monitor MCA according to claim 4, characterized in that: In step three, the layout design file of each layer and the corresponding basic cell array are overlapped. The overlapping operation process is as follows: all basic cells of each layer are overlapped with the planar layout of the layout design file of the layer. The basic cells corresponding to the overlapping part of the non-metal design lines in the layout design file of the layer are marked as 1. The marking judgment rule is that unless a basic cell has no overlap with any non-metal line in the layout design file of the layer, it is determined that there is an overlapping part. Then, the number corresponding to the basic cell is marked as 1. The basic cell is the target cell.

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