Reactor core power monitoring system of heat pipe micro reactor

Abstract

The invention provides a reactor core power monitoring system of a heat pipe micro reactor, and relates to the technical field of nuclear reactors. The reactor core power monitoring system of the heat pipe micro-reactor comprises a data acquisition unit and a data processing unit, the data acquisition unit is used for acquiring out-of-reactor detector signals and reactor core state information, the data processing unit is connected with the data acquisition unit, the data processing unit comprises a power level monitoring unit and a power distribution monitoring unit, and the power level monitoring unit is connected with the power distribution monitoring unit. The power level monitoring unit is used for obtaining the reactor core power level based on the out-of-pile detector signal and the reactor core state information, and the power distribution monitoring unit is used for obtaining the reactor core power distribution based on the out-of-pile detector signal and the reactor core state information. Based on the reactor core power monitoring system, the reactor core power of the heat pipe micro reactor can be rapidly and accurately monitored.

Description

Technical Field

[0001] The present application relates to the technical field of nuclear reactors, and in particular to a core power monitoring system for a heat pipe micro-reactor. Background Art

[0002] In recent years, with the development and maturity of heat pipe technology, heat pipe cooling reactors have received more and more attention. At present, various countries have successively proposed a variety of new heat pipe reactor design schemes, covering a wide range of applications.

[0003] The core monitoring of the reactor plays a very important role in the startup, operation and safety protection of the reactor, and is an indispensable key system in the reactor. The unmanned and autonomous control of micro reactors has become a future development trend. Different from conventional pressurized water reactors, micro heat pipe cooled reactors (referred to as heat pipe micro reactors) have the characteristics of small size, compact structure, low power and high temperature. The core design is quite different from that of conventional pressurized water reactors, which makes it difficult for existing monitoring methods to be applied to heat pipe micro reactors. Summary of the invention

[0004] In order to alleviate, mitigate or eliminate the above-mentioned technical problems, the present application provides a core power monitoring system for a heat pipe micro-reactor, which can realize fast and accurate monitoring of the core power of the heat pipe micro-reactor.

[0005] In a first aspect, the present application provides a core power monitoring system for a heat pipe micro-reactor, comprising:

[0006] A data acquisition unit, used to obtain the external detector signals and core status information;

[0007] A data processing unit is connected to the data acquisition unit, and the data processing unit includes a power level monitoring unit and a power distribution monitoring unit, wherein the power level monitoring unit is used to obtain the core power level based on the ex-core detector signal and the core status information, and the power distribution monitoring unit is used to obtain the core power distribution based on the ex-core detector signal and the core status information.

[0008] In a possible implementation, obtaining the core power level based on the ex-core detector signal and the core state information includes:

[0009] Obtaining the relationship between the power level detector signal and the core power level under different core states;

[0010] A core power level is obtained based on the relationship, the ex-core detector signal and the core state information.

[0011] In a possible implementation, obtaining the core power distribution based on the external detector signal and the core state information includes:

[0012] Acquire an ex-core detector response function based on the core state information;

[0013] A core power distribution is obtained based on the ex-core detector signal and the ex-core detector response function.

[0014] In a possible implementation, obtaining the core power distribution based on the ex-core detector signal and the ex-core detector response function includes:

[0015] Solve the following equation to obtain the core power distribution:

[0016] D=C n R,

[0017] Where D is the out-of-core detector signal, C n is the response function of the ex-core detector, and R is the reconstructed value of the core power distribution.

[0018] In a possible implementation, the power distribution monitoring unit is further used to construct an ex-core detector response function database, and the acquiring of the ex-core detector response function based on the core state information includes:

[0019] The ex-core detector response function is acquired from the ex-core detector response function database based on the core state information.

[0020] In a possible implementation, building an off-heap detector response function database includes:

[0021] Obtain core geometry and material information;

[0022] Constructing a conjugate neutron transport calculation model or a neutron transport calculation model based on the core geometry and material information;

[0023] Obtaining a conjugate neutron fluence rate based on the conjugate neutron transport calculation model, or obtaining a neutron fluence rate based on the neutron transport calculation model;

[0024] Obtaining an ex-core detector response coefficient based on the conjugate neutron fluence rate or the neutron fluence rate;

[0025] Obtaining an ex-core detector response function based on the ex-core detector response coefficient;

[0026] The ex-core detector response functions under different core states are combined into an ex-core detector response function database.

[0027] In a possible implementation, obtaining the ex-core detector response coefficient based on the conjugate neutron fluence rate or the neutron fluence rate includes:

[0028] The response coefficient of the out-of-core detector is obtained according to the following formula:

[0029] or

[0030] Among them, c i,j is the response coefficient of the out-of-pile detector, V i is the volume of fuel zone i, χ i is the fission neutron spectrum of fuel zone i, is the conjugate neutron fluence rate of fuel zone i produced by detector j, ∑ j is the neutron response cross section of detector j, is the neutron flux rate of fuel zone i produced by detector j, i = 1, 2, ..., N f , N f Indicates the number of fuel zones, j = 1, 2, ..., N d , N d Indicates the number of off-heap detectors.

[0031] In a possible implementation, obtaining the ex-core detector response function based on the ex-core detector response coefficient includes:

[0032] The off-heap detector response function is obtained according to the following formula:

[0033]

[0034] Among them, C n is the off-heap detector response function, c i,j is the response coefficient of the out-of-pile detector, i=1,2,…,N f , N f Indicates the number of fuel zones, j = 1, 2, ..., N d , N d Indicates the number of off-heap detectors.

[0035] In one possible implementation, the ex-core detector includes a radial ex-core detector located in the radial direction of the core and an axial ex-core detector located in the axial direction of the core. The radial ex-core detector is located in the middle of the core active zone, and the axial ex-core detector is located on the opposite side of the core heat pipe penetration end and on the axial extension line of the core active zone.

[0036] In a possible implementation, the core status information includes at least one of the temperature inside the core, control body operation information and core burnup.

[0037] Compared with the prior art, this application has the following advantages:

[0038] The core power monitoring system of the heat pipe micro-reactor provided by the present application includes a data acquisition unit for acquiring an external detector signal and core state information, and a data processing unit connected to the data acquisition unit, the data processing unit includes a power level monitoring unit and a power distribution monitoring unit, wherein the power level monitoring unit is used to obtain the core power level based on the external detector signal and the core state information, and the power distribution monitoring unit is used to obtain the core power distribution based on the external detector signal and the core state information. Based on the core power monitoring system, the core power of the heat pipe micro-reactor can be quickly and accurately monitored. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings are included to provide a further understanding of the present application. They are included and constitute a part of the present application. The accompanying drawings illustrate embodiments of the present application and together with the present specification serve to explain the principles of the present application. In the accompanying drawings:

[0040] Figure 1 is a schematic top view of a core structure of a heat pipe micro-reactor provided in an embodiment of the present application;

[0041] Figure 2 It is a structural schematic diagram of a core power monitoring system of a heat pipe micro-reactor provided in an embodiment of the present application;

[0042] Figure 3 is a side view schematic diagram of the position of an out-of-core detector provided in an embodiment of the present application;

[0043] Figure 4 is a top view schematic diagram of the position of an off-core detector provided in an embodiment of the present application;

[0044] Figure 5 It is a flow chart of a core power distribution monitoring method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0045] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0046] As shown in this application, unless the context clearly indicates an exception, the words "a", "an", "a kind" and / or "the" do not refer to the singular, but also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0047] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the application. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to actual proportional relationships. The technology, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0048] In the description of the present application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present application; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0049] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0050] In addition, although the terms used in this application are selected from well-known and commonly used terms, some of the terms mentioned in this application specification may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this article. In addition, it is required to understand this application not only by the actual terms used, but also by the meaning implied by each term.

[0051] It should be understood that when a component is referred to as being “on another component,” “connected to another component,” “coupled to another component,” or “contacting another component,” it can be directly on, connected to, coupled to, or contacting the other component, or intervening components may be present. In contrast, when a component is referred to as being “directly on another component,” “directly connected to,” “directly coupled to,” or “directly contacting” another component, there are no intervening components present.

[0052] Flowcharts are used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed accurately in order. On the contrary, various steps may be processed in reverse order or simultaneously. At the same time, other operations may be added to these processes, or one or more operations may be removed from these processes.

[0053] Figure 1 1 is a top view schematic diagram of a core structure of a heat pipe micro-reactor provided in an embodiment of the present application. Figure 1 As shown, the core of the heat pipe micro-reactor includes a reactor vessel 110 and a shielding layer 120 sleeved outside the reactor vessel 110. Fuel assemblies 101, shutdown rods 102, reflective layers 103 and control drums are arranged in the reactor vessel 110, and the reactor vessel 110 is sleeved outside the reflective layer 103. The control body of the core includes components such as the control drum and the shutdown rod 102. The control drum includes an adjustment drum 104, a shutdown drum 105 and a compensation drum 106, and the adjustment drum 104, the shutdown drum 105 and the compensation drum 106 are evenly arranged along the circumference of the core. It can be understood that the core is not limited to the structure of this embodiment, but can have different changes. For example, some components can be changed or omitted, or additional components can be added.

[0054] Since heat pipe micro-reactors have the characteristics of small size, compact structure, low power and high temperature, their core design is quite different from that of conventional pressurized water reactors, making it difficult to apply existing monitoring methods to heat pipe micro-reactors.

[0055] Figure 2 Schematic diagram of the structure of a core power monitoring system of a heat pipe micro-reactor provided in an embodiment of the present application. Figure 2As shown, the core power monitoring system 200 includes a data acquisition unit 210 for acquiring data, and a data processing unit 220 connected to the data acquisition unit 210. The data processing unit 220 obtains the core power level and the core power distribution based on the data acquired by the data acquisition unit 210. In some embodiments, the core power monitoring system 200 also includes a display unit or a post-processing unit connected to the data processing unit 220, the display unit visually outputs the core power level and the core power distribution obtained by the data processing unit 220, and the post-processing unit outputs the core power level and the core power distribution.

[0056] The data acquired by the data acquisition unit 210 include the ex-core detector signal and the core state information, wherein the core state information may include the in-core temperature, the control body operation information and other information characterizing the core state. In practical applications, the data acquisition unit 210 acquires the ex-core detector signal from the ex-core nuclear measurement system, acquires the in-core temperature from the temperature monitoring system, and acquires the control body operation information from the control system, wherein the control body operation information includes the control drum position information. It should be noted that the information characterizing the core state can be changed, such as removing the in-core temperature or increasing the core burnup.

[0057] In some embodiments, the core power monitoring system 200 further includes a signal preprocessing unit connected to the data acquisition unit 210 and the data processing unit 220. The signal preprocessing unit calibrates and corrects the acquired ex-core detector signal and then transmits it to the data processing unit 220.

[0058] The data processing unit 220 includes a power level monitoring unit 221 and a power distribution monitoring unit 222. The power level monitoring unit 221 is used to obtain the core power level based on the external detector signal and the core state information, and the power distribution monitoring unit 222 is used to obtain the core power distribution based on the external detector signal and the core state information.

[0059] The embodiment of the present application only uses off-core detectors to monitor the core power. The detector deployment position is not restricted by the active area structure, the operating environment is relatively good and the maintenance is relatively simple. It is suitable for heat pipe micro-reactors without space for detector arrangement in the reactor.

[0060] In some embodiments, please refer to Figure 3-Figure 4The ex-core detectors include radial ex-core detectors 311 located in the radial direction of the core and axial ex-core detectors 312 located in the axial direction of the core. The radial ex-core detector 311 is located in the middle of the core active area, and the axial ex-core detector 312 is located on the opposite side of the core heat pipe penetration end and on the axial extension line of the core active area. In practical applications, the radial ex-core detector 311 and the axial ex-core detector 312 are arranged as close to the shielding layer 120 as possible, and are at an appropriate distance from the shielding layer 120 according to the specific structure of the core, and each detector is arranged as symmetrically as possible on the symmetry line of the core.

[0061] In a specific embodiment, the axial ex-core detector 312 includes 6 detectors, and the radial ex-core detector 311 includes 8 detectors. Figure 4 As shown, D1-D6 are axial ex-core detectors, and D7-D14 are radial ex-core detectors. It can be understood that the arrangement of the ex-core detectors is not limited to this embodiment, but can be varied. For example, some detectors can be changed or omitted, or additional detectors can be added.

[0062] The embodiment of the present application utilizes a method of combining an axial ex-pillar detector with a radial ex-pillar detector to overcome the problem that the ex-pillar detector acquires little internal information.

[0063] In practical applications, the power level monitoring unit 221 and the power distribution monitoring unit 222 both use radial and axial ex-core detector signals, and share some detector signals, thereby improving the utilization of ex-core detector information and saving reactor layout space. Figure 4 The power level monitoring unit 221 uses the measurement signals of detectors D1-D6, D9-D10 and D13-D14, and the power distribution monitoring unit 222 uses the measurement signals of detectors D1-D8 and D10-D13.

[0064] In some embodiments, the power level monitoring unit 221 obtains the core power level based on the ex-core detector signal and the core state information, specifically including: obtaining the relationship between the power level detector signal and the core power level under different core states, and then obtaining the core power level based on the relationship, the ex-core detector signal and the core state information. For example, the calibration coefficients of the power level detector signal and the core power level under different core states (such as different core burnup, different control drum positions) are obtained through experiments or numerical simulations, and the relationship between the power level detector signal and the core power level under different core states is constructed based on the calibration coefficients, and the relationship can be a linear relationship or a nonlinear relationship, and then the core power level is obtained by combining the obtained ex-core detector signal and the core state information.

[0065] In some embodiments, the power distribution monitoring unit 222 obtains the core power distribution based on the ex-core detector signal and the core state information, specifically including: obtaining the ex-core detector response function based on the core state information, and then obtaining the core power distribution based on the ex-core detector signal and the ex-core detector response function. The power distribution monitoring unit 222 can calculate the ex-core detector response function online or offline. For example, the power distribution monitoring unit 222 constructs an ex-core detector response function database offline, and then selects the ex-core detector response function under the corresponding core state from the ex-core detector response function database online based on the core state information obtained in real time.

[0066] Please refer to Figure 5 The core power distribution monitoring process of the core power monitoring system includes the following:

[0067] Step 501: construct an off-heap detector response function database.

[0068] In practical applications, the power distribution monitoring unit 222 of the core power monitoring system can construct an off-line ex-core detector response function database. The embodiment of the present application does not limit the construction method of the ex-core detector response function database. In order to better understand the present application, the following exemplary method for constructing an ex-core detector response function database is given:

[0069] Step 511, obtain core geometry and material information.

[0070] Step 512: construct a conjugate neutron transport calculation model or a neutron transport calculation model based on core geometry and material information.

[0071] Step 513: Obtain a conjugate neutron fluence rate based on a conjugate neutron transport calculation model, or obtain a neutron fluence rate based on a neutron transport calculation model.

[0072] Step 514: Obtain an ex-core detector response coefficient based on the conjugate neutron fluence rate or the neutron fluence rate.

[0073] In some embodiments, the ex-pile detector response coefficient is obtained according to the following formula:

[0074] or

[0075] Among them, c i,j is the response coefficient of the out-of-pile detector, V i is the volume of fuel zone i, χ i is the fission neutron spectrum of fuel zone i, is the conjugate neutron fluence rate of fuel zone i produced by detector j, ∑ j is the neutron response cross section of detector j, is the neutron flux rate of fuel zone i produced by detector j, i = 1, 2, ..., N f , N f Indicates the number of fuel zones, j = 1, 2, ..., N d , N d Indicates the number of off-heap detectors.

[0076] Step 515: Obtain the ex-core detector response function based on the ex-core detector response coefficient.

[0077] In some embodiments, the off-pillar detector response function is obtained according to the following formula:

[0078]

[0079] Among them, C n is the off-heap detector response function.

[0080] Step 516: The ex-core detector response functions under different core states are combined into an ex-core detector response function database.

[0081] In some embodiments, the core power distribution is obtained by solving the following equation:

[0082] D=C n R,

[0083] Where D is the out-of-core detector signal, C n is the response function of the ex-core detector, and R is the reconstructed value of the core power distribution.

[0084] Step 502: Acquire the external core detector signal and core status information.

[0085] In practical applications, the data acquisition unit 210 of the core power monitoring system can obtain the external detector signal and the core state information in real time. For example, the data acquisition unit 210 obtains the external detector signal D from the external nuclear measurement system, obtains the internal temperature T from the temperature monitoring system, and obtains the control body operation information Cp from the control system. The core state is characterized by the internal temperature T and the control body operation information Cp, which is expressed as (T, Cp) n , n = 1, 2, ..., N, N represents the number of core states. In some embodiments, the power distribution monitoring unit 222 in the data processing unit 220 can also calculate and obtain information such as core burnup Bu, and the core state is characterized by the core burnup Bu, the temperature inside the core T and the control body operation information Cp, which is expressed as (Bu, T, Cp, ...) n .

[0086] Step 503: Acquire the ex-core detector response function from the ex-core detector response function database based on the core state information.

[0087] Step 504: obtain core power distribution based on the ex-core detector signal and the ex-core detector response function.

[0088] Steps 503 and 504 may be performed online by the power distribution monitoring unit 222. For example, the power distribution monitoring unit 222 selects the ex-core detector response function C under the corresponding core state from the ex-core detector response function database. n , solve the following equation to obtain the core power distribution:

[0089] D=C n R,

[0090] Where D is the out-of-core detector signal, C n is the response function of the ex-core detector, and R is the reconstructed value of the core power distribution.

[0091] The basic concepts have been described above. Obviously, for those skilled in the art, the above disclosure is only an example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.

[0092] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0093] Some aspects of the present application may be performed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The above hardware or software may be referred to as "data blocks", "modules", "engines", "units", "components" or "systems". The processor may be one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DAPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, or combinations thereof. In addition, various aspects of the present application may be expressed as computer products located in one or more computer-readable media, which include computer-readable program codes. For example, computer-readable media may include, but are not limited to, magnetic storage devices (e.g., hard disks, floppy disks, tapes ...), optical disks (e.g., compact disks CDs, digital versatile disks DVDs ...), smart cards, and flash memory devices (e.g., cards, sticks, key drives ...).

[0094] A computer-readable medium may include a propagated data signal containing computer program code, such as in baseband or as part of a carrier wave. The propagated signal may have a variety of manifestations, including electromagnetic, optical, etc., or a suitable combination. A computer-readable medium may be any computer-readable medium other than a computer-readable storage medium, which may be connected to an instruction execution system, device or apparatus to communicate, propagate or transmit a program for use. The program code on the computer-readable medium may be propagated via any suitable medium, including radio, cable, fiber optic cable, radio frequency signal, or similar medium, or any combination of the above mediums.

[0095] Similarly, it should be noted that in order to simplify the description disclosed in this application and thus help understand one or more embodiments, in the above description of the embodiments of this application, multiple features are sometimes merged into one embodiment, figure or description thereof. However, this disclosure method does not mean that the subject of this application requires more features than the features mentioned. In fact, the features of the embodiment are less than all the features of the single embodiment disclosed above.

[0096] In some embodiments, numbers describing the number of components and attributes are used. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise specified, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification are approximate values, which may change according to the required features of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining the digits. Although the numerical domains and parameters used to confirm the breadth of the range in some embodiments of the present application are approximate values, in specific embodiments, the setting of such numerical values ​​is as accurate as possible within the feasible range.

[0097] Although the present application has been described with reference to the current specific embodiments, ordinary technicians in this technical field should recognize that the above embodiments are only used to illustrate the present application, and various equivalent changes or substitutions may be made without departing from the spirit of the present application. Therefore, as long as the changes and modifications to the above embodiments are within the scope of the essential spirit of the present application, they will fall within the scope of the present application.

Claims

1. A core power monitoring system for a heat pipe micro-reactor, characterized in that: include: A data acquisition unit, used to obtain the external detector signals and core status information; A data processing unit is connected to the data acquisition unit, and the data processing unit includes a power level monitoring unit and a power distribution monitoring unit, wherein the power level monitoring unit is used to obtain the core power level based on the ex-core detector signal and the core status information, and the power distribution monitoring unit is used to obtain the core power distribution based on the ex-core detector signal and the core status information.

2. The core power monitoring system according to claim 1, characterized in that: The obtaining of the core power level based on the off-core detector signal and the core state information comprises: Obtaining the relationship between the power level detector signal and the core power level under different core states; A core power level is obtained based on the relationship, the ex-core detector signal and the core state information.

3. The core power monitoring system according to claim 1, characterized in that: The obtaining of the core power distribution based on the off-core detector signal and the core state information comprises: Acquire an ex-core detector response function based on the core state information; A core power distribution is obtained based on the ex-core detector signal and the ex-core detector response function.

4. The core power monitoring system according to claim 3, characterized in that: The obtaining of the core power distribution based on the ex-core detector signal and the ex-core detector response function comprises: Solve the following equation to obtain the core power distribution: D=C n ·R, Where D is the out-of-core detector signal, C n is the response function of the ex-core detector, and R is the reconstructed value of the core power distribution.

5. The core power monitoring system according to claim 3, characterized in that: The power distribution monitoring unit is further used to construct an ex-core detector response function database, and obtaining the ex-core detector response function based on the core state information includes: The ex-core detector response function is acquired from the ex-core detector response function database based on the core state information.

6. The core power monitoring system according to claim 5, characterized in that: The constructing of the off-heap detector response function database comprises: Obtain core geometry and material information; Constructing a conjugate neutron transport calculation model or a neutron transport calculation model based on the core geometry and material information; Obtaining a conjugate neutron fluence rate based on the conjugate neutron transport calculation model, or obtaining a neutron fluence rate based on the neutron transport calculation model; Obtaining an ex-core detector response coefficient based on the conjugate neutron fluence rate or the neutron fluence rate; Obtaining an ex-core detector response function based on the ex-core detector response coefficient; The ex-core detector response functions under different core states are combined into an ex-core detector response function database.

7. The core power monitoring system according to claim 6, characterized in that: The obtaining of the ex-pile detector response coefficient based on the conjugate neutron fluence rate or the neutron fluence rate comprises: The response coefficient of the out-of-core detector is obtained according to the following formula: or Among them, c i,j is the response coefficient of the out-of-pile detector, V i is the volume of fuel zone i, χ i is the fission neutron spectrum of fuel zone i, is the conjugate neutron fluence rate of fuel zone i produced by detector j, ∑ j is the neutron response cross section of detector j, is the neutron flux rate of fuel zone i produced by detector j, i = 1, 2, ..., N f , N f Indicates the number of fuel zones, j = 1, 2, ..., N d , N d Indicates the number of off-heap detectors.

8. The core power monitoring system according to claim 6, characterized in that: The obtaining of the ex-pile detector response function based on the ex-pile detector response coefficient comprises: The off-heap detector response function is obtained according to the following formula: Among them, C n is the off-heap detector response function, c i,j is the response coefficient of the out-of-pile detector, i=1,2,…,N f , N f Indicates the number of fuel zones, j = 1, 2, ..., N d , N d Indicates the number of off-heap detectors.

9. The core power monitoring system according to claim 1, characterized in that: The ex-core detectors include radial ex-core detectors located in the radial direction of the core and axial ex-core detectors located in the axial direction of the core. The radial ex-core detectors are located in the middle of the core active area, and the axial ex-core detectors are located on the opposite side of the core heat pipe penetration end and on the axial extension line of the core active area.

10. The core power monitoring system according to claim 1, characterized in that: The core status information includes at least one of the core temperature, control body operation information and core burnup.

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