Method and device for calculating value of control rod by rod falling method, and electronic equipment

Abstract

The invention relates to the technical field of nuclear power station safety testing, in particular to a method and device for calculating the value of a control rod through a rod falling method and electronic equipment. The method comprises the following steps: acquiring an initial moment t0 and a neutron-flux density n0 corresponding to the initial moment t0 of a to-be-tested control rod before rod falling, a moment t1 when rod falling is finished and a neutron-flux density n1 corresponding to the moment t1 when rod falling is finished, and any moment t2 after rod falling is finished and a second neutron-flux density n2 corresponding to the any moment t2; calculating the period T1 of the moment after rod falling; and calculating the value rho1 of the control rod to be tested. According to the optimized formula, the influences of instant neutrons and delayed neutrons are considered at the same time, and therefore the measurement error of the rod falling method can be remarkably reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear power plant safety testing, and in particular relates to a method for calculating the value of a control rod by a drop rod method, a device thereof, and electronic equipment. Background Art

[0002] The total value of the reactor control rods is directly related to the shutdown margin of the reactor. The rod drop method measures the control rod value by obtaining the actual measured data of the rod drop shutdown through the power plant computer real-time data acquisition system, and then uses the offline digital reactivity instrument program to calculate the rod drop value. Assuming a very short time, the traditional rod drop method basically does not consider the contribution of delayed neutrons, while the rod drop time of a general reactor has reached the second level, and the half-life of two groups of delayed neutron precursor nuclei is less than 1 second. Therefore, if the influence of delayed neutrons is not considered, the calculation error of the rod drop method will be large. Summary of the invention

[0003] The purpose of the present invention is to propose a method and device and electronic equipment for calculating the value of a control rod by the drop rod method, so as to solve the technical problem of large calculation errors caused by the defect of not considering the contribution of delayed neutrons when calculating the value of a control rod by the traditional drop rod method.

[0004] A first aspect of the present invention provides a method for calculating the value of a control rod by a drop rod method, the method comprising:

[0005] Obtain the initial time t0 of the control rod to be tested before the rod drop begins and the neutron flux density n0 corresponding to the initial time t0, the time t1 when the rod drop ends and the neutron flux density n1 corresponding to the time t1 when the rod drop ends, and any time t2 after the rod drop ends and the neutron flux density n2 corresponding to any time t2;

[0006] According to the time t1 when the rod is dropped, the neutron flux density n1 corresponding to the time t1 when the rod is dropped, any time t2, and the neutron flux density n2 corresponding to any time t2, and combined with formula (1), the period T1 after the rod is dropped is calculated.

[0007]

[0008] Get the average generation time of prompt neutrons Λ, the effective share of the i-th group of delayed neutrons in all fission neutrons β ieff , the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i The total effective fraction of delayed neutrons in all fission neutrons is β eff , the time interval Δt before and after the rod falls;

[0009] According to the neutron flux density n0 corresponding to the initial time t0, the average generation time Λ of prompt neutrons, and the total effective share β of delayed neutrons in all fission neutronseff , the period T1 after the rod is dropped, the time interval Δt before and after the rod is dropped, and the effective share of the i-th group of delayed neutrons in all fission neutrons β ieff and the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i , combined with formula (2) to calculate the value of the control rod to be tested |ρ1|,

[0010]

[0011] In at least one embodiment of the present invention, obtaining the initial time t0 of the control rod to be tested before the rod drop begins and the neutron flux density n0 corresponding to the initial time t0, the time t1 when the rod drop ends after the rod drop ends and the neutron flux density n1 corresponding to the time t1 when the rod drop ends, and any time t2 after the rod drop ends and the neutron flux density n2 corresponding to any time t2 includes: before the rod drop test begins, confirming that the core is in a critical state; recording the initial time t0 of the control rod to be tested before the rod drop begins, and the neutron flux density n0 corresponding to the initial time t0 measured by an out-of-core nuclear instrument; at the beginning of the rod drop test, inserting the control rod to be tested to the bottom of the reactor; after the rod drop test ends, recording the neutron flux density n1 corresponding to the time t1 when the rod drop ends and the time t1 when the rod drop ends measured by an out-of-core nuclear instrument, and any time t2 after the rod drop ends and the neutron flux density n2 corresponding to any time t2 measured by an out-of-core nuclear instrument.

[0012] A second aspect of the present invention provides a device for calculating the value of a control rod by a drop rod method, the device comprising an acquisition module and a calculation module.

[0013] The acquisition module is used to obtain the initial time t0 of the control rod to be tested before the rod drop begins and the neutron flux density n0 corresponding to the initial time t0, the time t1 when the rod drop ends and the neutron flux density n1 corresponding to the time t1 when the rod drop ends, and any time t2 after the rod drop ends and the neutron flux density n2 corresponding to any time t2, and obtain the average generation time Λ of the prompt neutrons, the effective share β of the i-th group of delayed neutrons in all fission neutrons ieff , the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i The total effective fraction of delayed neutrons in all fission neutrons is β eff .

[0014] The calculation module is used to calculate the period T1 after the rod drop according to the time t1 when the rod drop ends, the neutron flux density n1 corresponding to the time t1 when the rod drop ends, any time t2, and the neutron flux density n2 corresponding to any time t2, and in combination with formula (1).

[0015]

[0016] According to the neutron flux density n0 corresponding to the initial time t0, the average generation time Λ of prompt neutrons, and the total effective share β of delayed neutrons in all fission neutrons eff , the period T1 after the rod is dropped, the time interval Δt before and after the rod is dropped, and the effective share of the i-th group of delayed neutrons in all fission neutrons β ieff and the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i , combined with formula (2) to calculate the value of the control rod to be tested |ρ1|,

[0017]

[0018] The third aspect of the present invention provides a computer-readable storage medium having computer executable instructions stored thereon, which, when executed by a processor, implements a method of calculating the value of a control rod by a drop rod method according to the first aspect of the present invention.

[0019] The fourth aspect of the present invention provides an electronic device, which includes a processor and a memory. The processor is used to execute a method for calculating the value of a control rod by a drop rod method according to the first aspect of the present invention; and the memory is used to store executable instructions of the processor.

[0020] Beneficial effects of the present invention:

[0021] Compared with the traditional method of calculating the value of control rods, the optimized drop-rod method takes into account the effects of both prompt neutrons and delayed neutrons, thereby significantly reducing the calculation error of the drop-rod method. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A flow chart of a method for calculating the value of a control rod by a drop rod method provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The technical solution of the present invention is clearly and completely described below in conjunction with specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0024] like Figure 1 At least one embodiment of the present invention provides a method for calculating the value of a control rod by a drop rod method, and the execution subject of the method may be a processor or a server. The method comprises the following steps:

[0025] S1: Obtain the initial time t0 of the control rod to be tested before the rod drop begins and the neutron flux density n0 corresponding to the initial time t0, the time t1 when the rod drop ends and the neutron flux density n1 corresponding to the time t1 when the rod drop ends, and any time t2 after the rod drop ends and the neutron flux density n2 corresponding to any time t2.

[0026] In at least one embodiment of the present invention, steps S1.1 to S1.4 are a specific implementation of step S1.

[0027] S1.1: Before the rod drop test begins, confirm that the core is in a critical state.

[0028] S1.2: Record the initial time t0 of the control rod to be tested before the rod drop begins, and the neutron flux density n0 corresponding to the initial time t0 measured by the out-of-core nuclear instrument.

[0029] S1.3: At the beginning of the rod drop test, insert the control rod to be tested to the bottom of the pile.

[0030] S1.4: After the rod drop test is completed, record the neutron flux density n1 corresponding to the time t1 at which the control rod to be tested is dropped and the time t1 at which the rod drop is completed measured by the out-of-core nuclear instrument, as well as the neutron flux density n2 corresponding to any time t2 after the rod drop is completed and any time t2 at which the rod drop is completed measured by the out-of-core nuclear instrument.

[0031] S2: Based on the time t1 when the rod is dropped, the neutron flux density n1 corresponding to the time t1 when the rod is dropped, any time t2, and the neutron flux density n2 corresponding to any time t2, and combined with formula (1), calculate the period T1 after the rod is dropped.

[0032]

[0033] S3: Obtain the average generation time of prompt neutrons Λ, the effective share of the i-th group of delayed neutrons in all fission neutrons β ieff , the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i , the total effective fraction of delayed neutrons in all fission neutrons β eff and the time interval Δt before and after the rod falls.

[0034] S4: According to the neutron flux density n0 corresponding to the initial time t0, the average generation time of prompt neutrons Λ, and the total effective share of delayed neutrons in all fission neutrons β eff , the period T1 after the rod is dropped, the time interval Δt before and after the rod is dropped, and the effective share of the i-th group of delayed neutrons in all fission neutrons β ieff and the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i , combined with formula (2), calculate the value of the control rod to be tested |ρ1|.

[0035]

[0036] At least one embodiment of the present invention further provides a device for calculating the value of a control rod by a rod drop method, the calculation device comprising an acquisition module and a calculation module. The acquisition module is used to acquire the initial time t0 before the rod drop begins and the neutron flux density n0 corresponding to the initial time t0, the time t1 when the rod drop ends and the neutron flux density n1 corresponding to the time t1 when the rod drop ends, and any time t2 after the rod drop ends and the neutron flux density n2 corresponding to any time t2; and to acquire the average generation time Λ of prompt neutrons, the effective share β of the i-th group of delayed neutrons in all fission neutrons ieff , the time interval Δt before and after the rod drop, the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i The total effective fraction of delayed neutrons in all fission neutrons is β eff ; A calculation module is used to calculate the period T1 after the rod drop according to the time t1 when the rod drop ends, the neutron flux density n1 corresponding to the time t1 when the rod drop ends, any time t2 and the neutron flux density n2 corresponding to any time t2, and in combination with formula (1),

[0037]

[0038] According to the neutron flux density n0 corresponding to the initial time t0, the average generation time Λ of prompt neutrons, and the total effective share β of delayed neutrons in all fission neutrons eff , the period T1 after the rod is dropped, the time interval Δt before and after the rod is dropped, and the effective share of the i-th group of delayed neutrons in all fission neutrons β ieff and the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i , combined with formula (2) to calculate the value of the control rod to be tested |ρ1|,

[0039]

[0040] The calculation device is a device corresponding to the method for measuring the value of control rods in a nuclear power plant by the rod-drop method provided in the above-mentioned embodiment of the present invention, and therefore can at least achieve the above-mentioned corresponding technical effects, which will not be repeated here.

[0041] At least one embodiment of the present invention also provides an electronic device, which includes a processor and a memory. The memory is used to store instructions that can be executed by the processor, such as applications. The number of processors can be one or more. The application stored in the memory may include one or more modules, each corresponding to a set of instructions. In addition, the processor is configured to execute instructions to execute the method of calculating the value of the control rod by the above-mentioned drop rod method. The electronic device may also include a power supply component configured for power management of the electronic device, a wired or wireless network interface configured to connect the electronic device to a network, and an input / output (I / O) interface. The electronic device can operate based on an operating system stored in the memory, such as Windows ServerTM, Mac OSXTM, UnixTM, LinuxTM, FreeBSDTM or the like.

[0042] At least one embodiment of the present invention further provides a computer-readable storage medium. When the instructions in the storage medium are executed by the processor of the electronic device, the electronic device can execute a method for calculating the value of a control rod by the rod drop method. The method is executed by an agent program, and the method includes obtaining the initial time t0 before the rod drop begins and the neutron flux density n0 corresponding to the initial time t0, the time t1 when the rod drop ends and the neutron flux density n1 corresponding to the time t1 when the rod drop ends, and any time t2 after the rod drop ends and the neutron flux density n2 corresponding to any time t2; according to the time t1 when the rod drop ends, the neutron flux density n1 corresponding to the time t1 when the rod drop ends, any time t2 and the neutron flux density n2 corresponding to any time t2, and in combination with formula (1), calculate the period T1 of the time after the rod drop.

[0043]

[0044] Get the average generation time of prompt neutrons Λ, the effective share of the i-th group of delayed neutrons in all fission neutrons β ieff , the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i The total effective fraction of delayed neutrons in all fission neutrons is β eff , the time interval Δt before and after the rod is dropped; according to the neutron flux density n0 corresponding to the initial time t0, the average generation time Λ of prompt neutrons, and the total effective share β of delayed neutrons in all fission neutrons eff , the period T1 after the rod is dropped, the time interval Δt before and after the rod is dropped, and the effective share of the i-th group of delayed neutrons in all fission neutrons β ieff and the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i , combined with formula (2), calculate the value of the control rod to be tested |ρ1|.

[0045]

[0046] Those skilled in the art will appreciate that the algorithm steps of each example described in conjunction with the embodiments disclosed in the present invention can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0047] In the several embodiments provided by the present invention, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device embodiments described above are only illustrative, for example, the division of modules is only a logical function division, and there may be other division methods in actual implementation, such as multiple modules can be combined or integrated into another system, or some features can be ignored or not executed.

[0048] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program check codes.

[0049] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the computing device and the electronic device described above can refer to the corresponding processes in the aforementioned computing method embodiments, and will not be repeated here.

[0050] In order to understand the present invention more clearly, the inventive concept of the present invention is described as follows. The corresponding principle of the drop rod method and the influence of delayed neutrons are deduced as follows. According to the neutron density n0 before the drop rod; the neutron density n1 after the drop rod; the reactivity ρ0 before the drop rod; the reactivity ρ1 after the drop rod; the effective share β of the i-th group of delayed neutrons in all fission neutrons ieff ; The total effective fraction of delayed neutrons in all fission neutrons β eff; Average generation time of prompt neutrons Λ; Precursor concentration of delayed neutrons in group i at time t C i (t); the time interval Δt before and after the rod drop; the intensity of the external neutron source q; the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i ; After the rod drop, the reactor cycle is T1, and the neutron kinetic equations before the rod drop are described as formula (3) and formula (4).

[0051]

[0052]

[0053] The neutron kinetic equations of the drop-rod post-point reactor are described as equations (5) and (6).

[0054]

[0055]

[0056] Formula (7) and formula (8) are obtained by subtracting the point pile neutron kinetic equations before and after the rod drop.

[0057]

[0058]

[0059] According to formula (7), we can get formula (9).

[0060]

[0061] In the above formula (9), If the state before the rod is dropped is critical, that is, ρ0 = 0, then formula (10) and formula (11) are obtained.

[0062]

[0063]

[0064] According to the above conditions, formula (8) can be obtained as formula (12).

[0065]

[0066] In the formula is an unknown quantity, but since the rod-dropping process takes a short time, For this purpose, we assume that the change of ci is equal to the product of the average change rate of this process ci(t) and time, which gives formula (13).

[0067]

[0068] According to formula (12) and formula (13), we get formula (14).

[0069]

[0070] Substituting formula (14) into formula (9), we obtain the reactivity formula (15) introduced by control rod drop.

[0071]

[0072] The traditional differential formula is formula (16).

[0073]

[0074] Compared with the traditional differential formula (16), formula (15) has two more terms. The effect of prompt neutron changes is taken into account. This term can be ignored only when the prompt neutron change ends and the neutron density changes to the asymptotic value, that is, the period T1 is large enough.

[0075] The second extra item The effect of delayed neutrons is taken into account, and its contribution is positively correlated with Δt. This term can be ignored when Δt is small enough.

[0076] In order to verify the accuracy of the improved formula, a comparative explanation is given. The reactor is initially in a critical state, assuming that the rod drop time is extremely short, reaching 1E-4s, the rod drop value is 1000pcm, and the delayed neutron data are shown in Table 1.

[0077] Table 1 Delayed neutron data

[0078]

[0079] The results of the conventional rod dropping method and the optimized rod dropping method after the rod dropping are shown in Table 2.

[0080] Table 2 Comparison of the results of the drop rod method when the rod is dropped instantaneously

[0081]

[0082] As can be seen from Table 2, at the initial moment after the instantaneous rod drop, both methods cannot obtain the rod drop value, because the calculation still uses the previous value, and the rod has not completely dropped at this time. After the time reaches 0.0002 seconds, the optimized method can begin to give correct results, while the traditional rod drop method can only give correct results after 0.01 seconds, because the prompt neutrons also need enough time to decay. At 1 second, the traditional rod drop method produces a large error, while the error of the optimized rod drop method is much smaller, because after a long time, the influence of the delayed neutron precursor nucleus can no longer be ignored, and the traditional rod drop method does not consider the delayed neutrons, resulting in a large error.

[0083] Table 3 simulates the rod drop of a general commercial pressurized water reactor. The rod drop time is in the order of seconds, which is 1.85 seconds. If other conditions are the same as the previous example, the results of several methods after the rod drop are as shown in Table 3. As can be seen from the table, after the control rod falls to the bottom, the error of the traditional rod drop method has exceeded 30%, and the error of the optimized rod drop method is significantly reduced. This is because the influence of the delayed neutron precursor nucleus with the rod drop time in the order of seconds cannot be ignored.

[0084] Table 3 Comparison of the results of the drop rod method when simulating the drop rod

[0085]

[0086] Through the above comparison, it is found that the optimized falling-rod method can significantly reduce the measurement error of the falling-rod method compared with the traditional method by taking into account the influence of prompt neutrons and delayed neutrons.

[0087] Taking the time interval Δt before and after the rod drop as 1.85 seconds as an example, the reactivity is calculated as follows.

[0088] Optimized falling rod method formula Λ、λ i , β ieff and β eff These are all neutronic parameters, which are considered constants during the experiment and can be calculated from theoretical data. Here, we take the data in Table 1, and Λ is 2.69×10 -5 s.

[0089] Before the test begins, confirm that the core is in a critical state. At the start of the test, the control rod to be tested is inserted down to the bottom of the reactor.

[0090] Before the rod drop, t0=0, and the corresponding signal value of the out-of-core instrument is recorded as n0=1; according to the rod drop time, the end time of the rod drop is determined as t1=1.85, and the corresponding signal value of the out-of-core instrument is recorded as n1=0.337541; select any time t2=2 after the rod drop, and record the corresponding signal value of the out-of-core instrument as n2=0.331106. Among them, t0 and t1 are determined according to the actual rod drop time, and t2 can be any time point after the rod drop ends. t2 is taken to calculate the period T1 after the rod drop, so As a ratio, the signal can be taken as mid-range or power range.

[0091] Δt=t1-t0=1.85

[0092]

[0093] Substituting the above values ​​and the delayed neutron parameter into formula (2), the reactivity after the rod drop can be obtained:

[0094]

[0095] Then the value of the control rod to be tested is |ρ1|=1088.3pcm.

[0096] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the attached claims.

Claims

1. A method for calculating the value of a control rod by a drop rod method, characterized in that: include: Obtaining an initial time t0 before the rod drop starts and a neutron flux density n0 corresponding to the initial time t0, a time t1 when the rod drop ends and a neutron flux density n1 corresponding to the time t1 when the rod drop ends, and an arbitrary time t2 after the rod drop ends and a neutron flux density n2 corresponding to the arbitrary time t2; According to the time t1 when the rod drop ends, the neutron flux density n1 corresponding to the time t1 when the rod drop ends, the arbitrary time t2, and the neutron flux density n2 corresponding to the arbitrary time t2, and in combination with formula (1), the period T1 after the rod drop is calculated. Get the average generation time of prompt neutrons Λ, the effective share of the i-th group of delayed neutrons in all fission neutrons β ieff , the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i The total effective fraction of delayed neutrons in all fission neutrons is β eff , the time interval Δt before and after the rod falls; According to the neutron flux density n0 corresponding to the initial time t0, the average generation time Λ of the prompt neutrons, the total effective fraction β of the delayed neutrons in all fission neutrons eff , the period T1 after the rod is dropped, the time interval Δt before and after the rod is dropped, the effective share β of the i-th group of delayed neutrons in all fission neutrons ieff and the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i , combined with formula (2), the value of the control rod to be tested |ρ1| is calculated.

2. The method according to claim 1, characterized in that The obtaining of the initial time t0 of the control rod to be tested before the rod dropping begins and the neutron flux density n0 corresponding to the initial time t0, the time t1 when the rod dropping ends after the rod dropping ends and the neutron flux density n1 corresponding to the time t1 when the rod dropping ends, and any time t2 after the rod dropping ends and the neutron flux density n2 corresponding to the any time t2 comprises: Before the rod drop test begins, confirm that the core is in a critical state; Recording the initial time t0 of the control rod to be tested before the rod drop begins, and the neutron flux density n0 corresponding to the initial time t0 measured by an out-of-core nuclear instrument; At the beginning of the rod drop test, the control rod to be tested is inserted down to the bottom of the pile; After the rod drop test is completed, the neutron flux density n1 corresponding to the time t1 at which the control rod to be tested is dropped and the time t1 at which the rod drop is completed measured by the out-of-core nuclear instrument, as well as the neutron flux density n2 corresponding to any time t2 after the rod drop is completed and the time t2 at which the rod drop is completed measured by the out-of-core nuclear instrument are recorded.

3. A device for calculating the value of a control rod by a drop rod method, characterized in that: include: The acquisition module is used to acquire the initial time t0 before the control rod under test starts to drop and the neutron flux density n0 corresponding to the initial time t0, the time t1 when the control rod under test ends to drop and the neutron flux density n1 corresponding to the time t1 when the control rod under test ends to drop, and the arbitrary time t2 after the control rod under test ends to drop and the neutron flux density n2 corresponding to the arbitrary time t2, and acquire the average generation time Λ of prompt neutrons, the effective proportion β of the i-th group of delayed neutrons in all fission neutrons ieff , the time interval Δt before and after the rod drop, the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i The total effective fraction of delayed neutrons in all fission neutrons is β eff ; a calculation module, for calculating the period T1 after the rod drop according to the time t1 at which the rod drop ends, the neutron flux density n1 corresponding to the time t1 at which the rod drop ends, the arbitrary time t2, and the neutron flux density n2 corresponding to the arbitrary time t2, and in combination with formula (1), According to the neutron flux density n0 corresponding to the initial time t0, the average generation time Λ of the prompt neutrons, the total effective share β of the delayed neutrons in all fission neutrons eff , the period T1 after the rod is dropped, the time interval Δt before and after the rod is dropped, the effective share β of the i-th group of delayed neutrons in all fission neutrons ieff and the decay constant λ of the i-th group of delayed neutron precursor nuclear fission fragments i , combined with formula (2), the value of the control rod to be tested |ρ1| is calculated.

4. A computer-readable storage medium having computer executable instructions stored thereon, characterized in that: When the executable instructions are executed by the processor, the method for calculating the value of a control rod by a drop rod method as claimed in claim 1 or 2 is implemented.

5. An electronic device, characterized in that: include: A processor, configured to execute the method for calculating the value of a control rod by a drop rod method as claimed in claim 1 or 2; and a memory for storing executable instructions of the processor.

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