A precise calculation method and automatic calculation system for lifting the upper limit of the reactor control rod bank of a third-generation pressurized water reactor nuclear power plant

Abstract

The application provides a precise calculation method and an automatic calculation system for the upper limit of a reactor control rod bank of a third-generation pressurized water reactor nuclear power plant. The precise calculation method can obtain the upper limit of the control rod bank under the conditions of any burnup, any power and any boron concentration, considering the actual operation of the reactor, and effectively supports the accurate control of the reactor by the nuclear power plant operators. In order to more conveniently and automatically calculate the upper limit of the control rod bank, the automatic calculation system is developed on the basis of the precise calculation method, thereby overcoming the shortcomings of long time consumption and high error rate of manual calculation, and further ensuring the accurate control of the upper limit of the control rod bank by the nuclear power plant operators. The automatic calculation system is repeatedly debugged and actually verified, proving the practicability of the upper limit of the control rod bank fast calculation system, and having a good industrial application prospect.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of nuclear power, and particularly relates to a precise calculation method and an automatic calculation system for lifting upper limit of a reactor control rod bank for a third-generation pressurized water reactor nuclear power plant. BACKGROUND

[0002] The movement of the control rod bank in the reactor core of the pressurized water reactor nuclear power plant follows certain lifting upper limit and operating lower limit requirements. The operating limit value management requirements of the control rod bank are different under different burnup, different power and different boron concentration conditions.

[0003] The reactor control rod bank of the third-generation pressurized water reactor nuclear power plant is divided into three types: axial power distribution control rod bank (AO rod bank, AO: Axial Operator), stop control rod bank (S rod bank, S: Stop) and temperature and power control rod bank (M rod bank).

[0004] The control rod bank moves in the area between the bottom of the reactor core and the top of the reactor core, and is 0 steps at the bottom of the reactor core and 264 steps at the top of the reactor core. The control rod bank step length is 264 steps, and the length of the bottom of the reactor core and the top of the reactor core is divided by 264 to obtain the step length of each step of the control rod bank.

[0005] The operating lower limit of the control rod bank only changes with the change of the power. The current power is expressed by percentage, and the operating lower limit of the control rod bank is as follows:

[0006] The axial power distribution control rod bank (AO rod bank, Axial Operator) has an operating lower limit of 150 steps in the range of 0% to 50% power, and an operating lower limit of (150+(current power x 100-50)) steps in the range of 50% to 100% power.

[0007] The stop control rod bank (S rod bank, Stop) has an operating lower limit of 264 steps in the range of 0% to 100% power.

[0008] The temperature and power control rod bank (also known as the mechanical rod bank, M rod bank, Mechnics) has an operating lower limit of 264 steps for the M2 sub-rod bank in the range of 0% to 100% power, an operating lower limit of (15+2x current power x 100) steps for the M1 sub-rod bank, and an operating lower limit of 0 steps for the MA, MB, MC and MD sub-rod banks.

[0009] Therefore, the operation lower limit of the control rod bank is calculated simply and only affected by the power, not by other factors. The operation lower limit of the control rod bank can be displayed in real time on the electronic system of the nuclear power plant.

[0010] Currently, the upper limit of the control rod bank in the nuclear power plant is controlled according to the report on the control rod bank upper limit value issued by the nuclear design unit (design institute). However, the report only displays the maximum boron concentration table corresponding to the predicted control rod bank upper limit under 8 typical burnups (a single table contains 11 typical powers and 18 typical total rod position conditions). Respectively as follows: 500MWd / tU (megawatt day per ton of uranium) maximum boron concentration value table corresponding to the predicted control rod bank upper limit;

[0011] 1000MWd / tU (megawatt day per ton of uranium) maximum boron concentration value table corresponding to the predicted control rod bank upper limit;

[0012] 2000MWd / tU (megawatt day per ton of uranium) maximum boron concentration value table corresponding to the predicted control rod bank upper limit;

[0013] 3000MWd / tU (megawatt day per ton of uranium) maximum boron concentration value table corresponding to the predicted control rod bank upper limit;

[0014] 4000MWd / tU (megawatt day per ton of uranium) maximum boron concentration value table corresponding to the predicted control rod bank upper limit;

[0015] 5000MWd / tU (megawatt day per ton of uranium) maximum boron concentration value table corresponding to the predicted control rod bank upper limit;

[0016] 6000MWd / tU (megawatt day per ton of uranium) maximum boron concentration value table corresponding to the predicted control rod bank upper limit;

[0017] 7000MWd / tU (megawatt day per ton of uranium) maximum boron concentration value table corresponding to the predicted control rod bank upper limit.

[0018] The maximum boron concentration value table corresponding to the predicted control rod group lifting upper limit under the eight typical burnups considers the maximum boron concentration value (RWL: Rod Without Limit) corresponding to the predicted control rod group lifting upper limit under the conditions of typical 11 powers and typical 18 total rod positions (MPI, Mechnics rods Position Index), and the unit is ppm (parts per million). The control rod group lifting upper limit is not displayed, and the nuclear power plant operator manually converts the maximum boron concentration corresponding to the predicted control rod group lifting upper limit into the control rod group lifting upper limit (rod position value). The manual calculation takes about 0.5 hours and is prone to calculation errors, which is inconvenient for the nuclear power plant operator to control the unit.

[0019] In addition, although the relevant prediction calculation according to the control rod lifting limit value report issued by the nuclear design unit (design institute) has approached the actual reactor operation condition, the difference between the prediction calculation and the actual reactor operation condition will affect the control rod group lifting upper limit. At present, the nuclear power plant operator cannot obtain the control rod lifting upper limit under the actual operation condition through the related report issued by the nuclear design unit (design institute).

[0020] In another aspect, the related electronic system of the current nuclear power plant does not have a display function of the control rod lifting upper limit.

[0021] In summary, it is a current urgent problem to provide a method for accurately calculating the reactor control rod group lifting upper limit under the conditions of any burnup, any power, and any boron concentration, and applying it to the actual situation and increasing the display function of the control rod lifting upper limit of the subsystem. SUMMARY

[0022] In view of the problems existing in the prior art, the purpose of the present application is to provide an accurate calculation method and automatic calculation system for the reactor control rod group lifting upper limit of a third-generation pressurized water reactor nuclear power plant. Through the correction and optimization calculation process of the predicted value and the actual value, the conversion of the related boron concentration value and the rod position value is not manually performed, the working time is saved, the requirements of the nuclear power plant operator for the control rod group lifting upper limit are met, the calculation speed is fast, and the calculation precision is high.

[0023] To achieve this purpose, the present application adopts the following technical solutions:

[0024] In a first aspect, the present application provides an accurate calculation method for the reactor control rod group lifting upper limit of a third-generation pressurized water reactor nuclear power plant, and the accurate calculation method comprises:

[0025] (1) Through the low-power physical test results and the theoretical calculation of the relevant data of the nuclear design document, the difference between the prediction calculation and the actual reactor operation is obtained, and then the relevant maximum boron concentration correction value is calculated;

[0026] (2) The maximum boron concentration table corresponding to the upper limit of the predicted control rod group lifting under 8 typical burnups issued by the nuclear design unit is recorded as an initial table; according to the initial table, an arbitrary burnup, a maximum boron concentration table corresponding to the upper limit of the predicted control rod lifting under the arbitrary power is calculated by an interpolation algorithm, and is recorded as table A;

[0027] According to the table A, a maximum boron concentration table corresponding to the upper limit of the predicted control rod lifting under the arbitrary burnup and the arbitrary power is calculated by an interpolation method, and is recorded as table B;

[0028] The table B is corrected by using the relevant maximum boron concentration correction value obtained by the step (1), and a maximum boron concentration table corresponding to the upper limit of the actual control rod lifting under the arbitrary burnup and the arbitrary power is obtained, and is recorded as table C;

[0029] According to the table C, a total rod position table under the arbitrary burnup, the arbitrary power and the arbitrary boron concentration is obtained by an interpolation method;

[0030] (3) The total rod position table in the step (2) is decomposed and calculated to obtain the upper limit of the actual control rod group under the arbitrary burnup, the arbitrary power and the arbitrary boron concentration;

[0031] The reactor control rod group comprises: an axial power distribution control rod group, which is recorded as an AO rod group;

[0032] A shutdown control rod group, which is recorded as an S rod group;

[0033] A temperature and power control rod group, which is recorded as an M rod group; the M rod group comprises six sub-rod groups of M1, M2, MA, MB, MC and MD.

[0034] The following is a preferred technical scheme of the present application, but is not a limitation of the technical scheme provided by the present application. Through the following technical scheme, the technical purpose and beneficial effects of the present application can be better achieved and realized.

[0035] As a preferred technical scheme of the present application, the low-power physical test results in the step (1) include an isothermal temperature coefficient measurement value, which is recorded as ITC measured ; the average boron concentration obtained by chemical sampling during the isothermal temperature coefficient measurement process is recorded as CB measured ; the boron 10 abundance measured during the low-power physical test is recorded as M B10 ; the average value of the average temperature of the moderator during the isothermal temperature coefficient measurement process is recorded as Tmod，measurement .

[0036] In the present application, the nuclear power plant staff will carry out low-power physical test during the process of restarting the reactor after each refueling overhaul, which is a routine test and will not be described here.

[0037] As a preferred technical solution of the present application, the nuclear design file related data in step (1) includes the end boron concentration prediction value, denoted as CB predicted ; the boron 10 abundance prediction value during the low-power physical test, whose default value is 19.9%; and the isothermal temperature coefficient prediction value, denoted as ITC predicted .

[0038] As a preferred technical solution of the present application, the specific method of step (1) includes:

[0039] The predicted and actual average boron concentration deviation is calculated by formula 1, denoted as ΔCB:

[0040] ΔCB = CB predicted - CB measured × (M B10 / 19.9%) Formula 1

[0041] ΔCB is judged by formula 2 to determine the boron concentration deviation revision isothermal temperature coefficient deviation coefficient, denoted as CF CB :

[0042] When ΔCB > 0, CF CB = 0.0182 pcm / ℃ / ppm

[0043] When ΔCB ≤ 0, CF CB = 0.0155 pcm / ℃ / ppm Formula 2

[0044] The boron concentration related isothermal temperature coefficient deviation is calculated by formula 3, denoted as ΔITC CB :

[0045] ΔITC CB = ΔCB × CF CB Formula 3

[0046] The moderator temperature deviation is calculated by formula 4, denoted as ΔT mod :

[0047] ΔT mod = 291.7℃ - T mod,measurement Formula 4

[0048] The moderator temperature deviation revision isothermal temperature coefficient deviation coefficient is calculated by formula 5, denoted as CF T mod :

[0049] When ΔT mod > 0, CF T mod = -0.2111 pcm / °C / °C

[0050] When ΔT mod ≤ 0, CF T mod = -0.2409 pcm / °C / °C Formula 5

[0051] The moderator temperature dependent isothermal temperature coefficient deviation is calculated by Formula 6, denoted as ΔITC T mod :

[0052] ΔITC T mod = ΔT mod × CF T mod Formula 6

[0053] The isothermal temperature coefficient revision value is calculated by Formula 7, denoted as ITC adjusted :

[0054] ITC adjusted = ITC measured + ΔITC CB + ΔITC T mod Formula 7

[0055] The isothermal temperature coefficient deviation is calculated by Formula 8, denoted as ΔITC Bias :

[0056] ΔITC Bias = ITC adjusted - ITC predicted Formula 8

[0057] The isothermal temperature coefficient deviation revision upper limit corresponding maximum boron concentration coefficient is calculated by Formula 9, denoted as CF ITC :

[0058] When ΔITC Bias > 0, CF ITC = 64.60 ppm / pcm / °C

[0059] When ΔITC Bias ≤ 0, CF ITC = 55.01 ppm / pcm / °C Formula 9

[0060] The difference between the predicted calculation and the actual reactor operation is obtained by Formula 10, and then the relevant maximum boron concentration correction value is calculated:

[0061] The relevant maximum boron concentration correction value = CF ITC × ΔITC Bias Formula 10.

[0062] As a preferred technical solution of the present application, according to the initial table, the table A in step (2) is obtained by formula 11; wherein, the maximum boron concentration value corresponding to the upper limit of the control rod bank lifting under the arbitrary fuel consumption is denoted as RWL predicted :

[0063] When the arbitrary fuel consumption ≤150MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the upper limit of the control rod bank lifting under the fuel consumption of 150MWd / tU;

[0064] When 150MWd / tU < the arbitrary fuel consumption ≤500MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the upper limit of the control rod bank lifting under the fuel consumption of 150MWd / tU and 500MWd / tU in the table, the RWL predicted under the same power and the same total rod position is the result of linear interpolation;

[0065] When 500MWd / tU < the arbitrary fuel consumption ≤1000MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the upper limit of the control rod bank lifting under the fuel consumption of 500MWd / tU and 1000MWd / tU in the table, the RWL predicted under the same power and the same total rod position is the result of linear interpolation;

[0066] When 1000MWd / tU < the arbitrary fuel consumption ≤2000MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the upper limit of the control rod bank lifting under the fuel consumption of 1000MWd / tU and 2000MWd / tU in the table, the RWL predicted under the same power and the same total rod position is the result of linear interpolation;

[0067] When 2000MWd / tU < the arbitrary fuel consumption ≤3000MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the upper limit of the control rod bank lifting under the fuel consumption of 2000MWd / tU and 3000MWd / tU in the table, the RWL predicted under the same power and the same total rod position is the result of linear interpolation;

[0068] When 3000MWd / tU < the arbitrary fuel consumption ≤4000MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the upper limit of the control rod bank lifting under the fuel consumption of 3000MWd / tU and 4000MWd / tU in the table, the RWL predicted under the same power and the same total rod position is the result of linear interpolation;

[0069] When 4000 MWd / tU < the arbitrary burnup ≤ 5000 MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the predicted control rod bank upper limit under the arbitrary burnup of 4000 MWd / tU and 5000 MWd / tU in the table, the RWL under the same power and the same total rod position predicted is the result of linear interpolation.

[0070] When 5000 MWd / tU < the arbitrary burnup ≤ 6000 MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the predicted control rod bank upper limit under the arbitrary burnup of 5000 MWd / tU and 6000 MWd / tU in the table, the RWL under the same power and the same total rod position predicted is the result of linear interpolation.

[0071] When 6000 MWd / tU < the arbitrary burnup ≤ 7000 MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the predicted control rod bank upper limit under the arbitrary burnup of 6000 MWd / tU and 7000 MWd / tU in the table, the RWL under the same power and the same total rod position predicted is the result of linear interpolation.

[0072] When the arbitrary burnup ≥ 7000 MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the predicted control rod bank upper limit under the arbitrary burnup of 7000 MWd / tU in the table, the RWL under the same power and the same total rod position

[0073] Preferably, according to the table A, the table B in step (2) is obtained by formula 12; wherein the maximum boron concentration value corresponding to the predicted control rod bank upper limit under the arbitrary burnup and the arbitrary power is denoted as RWL predicted * :

[0074] When 0% ≤ the arbitrary power < 10%, RWL predicted * = the RWL under the same total rod position in the table A under the arbitrary power of 0% and 10% predicted is the result of linear interpolation.

[0075] When 10% ≤ the arbitrary power < 20%, RWL predicted * = the RWL under the same total rod position in the table A under the arbitrary power of 10% and 20% predicted is the result of linear interpolation.

[0076] When 20% ≤ the arbitrary power < 30%, RWL predicted *= 20% and 30% power, the RWL at the same total rod position in Table A predicted the result of linear interpolation;

[0077] When 30% < the arbitrary power < 40%, RWL predicted * = 30% and 40% power, the RWL at the same total rod position in Table A predicted the result of linear interpolation;

[0078] When 40% < the arbitrary power < 50%, RWL predicted * = 40% and 50% power, the RWL at the same total rod position in Table A predicted the result of linear interpolation;

[0079] When 50% < the arbitrary power < 60%, RWL predicted * = 50% and 60% power, the RWL at the same total rod position in Table A predicted the result of linear interpolation;

[0080] When 60% < the arbitrary power < 70%, RWL predicted * = 60% and 70% power, the RWL at the same total rod position in Table A predicted the result of linear interpolation;

[0081] When 70% < the arbitrary power < 80%, RWL predicted * = 70% and 80% power, the RWL at the same total rod position in Table A predicted the result of linear interpolation;

[0082] When 80% < the arbitrary power < 90%, RWL predicted * = 80% and 90% power, the RWL at the same total rod position in Table A predicted the result of linear interpolation;

[0083] When 90% < the arbitrary power < 100%, RWL predicted * = 90% and 100% power, the RWL at the same total rod position in Table A predicted the result of linear interpolation Formula 12;

[0084] Preferably, the table B in step (2) is modified by formula 13 to obtain the table C: wherein the arbitrary fuel consumption, the maximum boron concentration value corresponding to the actual control rod group lifting upper limit under the arbitrary power, is denoted as RWL Final :

[0085] RWL Final =(RWL predicted * -CF ITC ×ΔITC Bias )×(19.9% / M B10 ) formula 13.

[0086] As a preferred technical solution of the present application, in the total rod position table in step (2), the total rod position value is oriented upwards / downwards by an integer.

[0087] As a preferred technical solution of the present application, the decomposition calculation in step (3) is performed by formula 14; wherein the total rod position is denoted as MPI; and the total rod position value interval module value is denoted as X MODEL :

[0088] When 531≤MPI≤768, X MODEL =1;

[0089] When 768<MPI≤780, X MODEL =2;

[0090] When 780<MPI≤949, X MODEL =3;

[0091] When 949<MPI≤1032, X MODEL =4;

[0092] When 1032<MPI≤1130, X MODEL =5;

[0093] When 1130<MPI≤1213, X MODEL =6;

[0094] When 1213<MPI≤1311, X MODEL =7;

[0095] When 1311<MPI≤1394, X MODEL =8;

[0096] When 1394<MPI≤1575, X MODEL =9 formula 14.

[0097] As a preferred technical solution of the present application, the decomposition calculation in step (3) further comprises determining the sequence of the leading rod group by formula 15:

[0098] When the reactor pilot rod group is an MA rod group, the pilot rod group sequence value sequence is 1;

[0099] When the reactor pilot rod group is an MD rod group, the pilot rod group sequence value sequence is 2 formula 15.

[0100] As a preferred technical solution of the present application, according to formula 16, the upper limit of the lifting of the AO rod group, the S rod group and the M rod group is calculated:

[0101] When X MODEL = 1, sequence = 2, MA = 0, MB = 0, MC = 0, MD = 0, M1 = MPI-531, M2 = 264, S = 264, AO = 264;

[0102] When X MODEL = 2, sequence = 2, MA = 0, MB = 0, MC = 0, MD = MPI-768, M1 = MPI-531, M2 = 264, S = 264, AO = 264;

[0103] When X MODEL = 3, sequence = 2, MA = 0, MB = 0, MC = 0, MD = MPI-768, M1 = 264, M2 = 264, S = 264, AO = 264;

[0104] When X MODEL = 4, sequence = 2, MA = 0, MB = 0, MC = MPI-942, MD = MPI-768, M1 = 264, M2 = 264, S = 264, AO = 264;

[0105] When X MODEL = 5, sequence = 2, MA = 0, MB = 0, MC = MPI-942, MD = 264, M1 = 264, M2 = 264, S = 264, AO = 264;

[0106] When X MODEL = 6, sequence = 2, MA = 0, MB = MPI-1123, MC = MPI-942, MD = 264, M1 = 264, M2 = 264, S = 264, AO = 264;

[0107] When X MODEL = 7, sequence = 2, MA = 0, MB = MPI-1123, MC = 264, MD = 264, M1 = 264, M2 = 264, S = 264, AO = 264;

[0108] When X_ MODEL =8, sequence=2, MA=MPI-1304, MB=MPI-1123, MC=264, MD=264, M1=264, M2=264, S=264, AO=264;

[0109] When X_ MODEL When =9 and sequence=2, MA=MPI-1304, MB=264, MC=264, MD=264, M1=264, M2=264, S=264, AO=264;

[0110] When X_ MODEL When sequence = 1, MD = 0, MC = 0, MB = 0, MA = 0, M1 = MPI-531, M2 = 264, S = 264, AO = 264;

[0111] When X_ MODEL =2, when sequence=1, MD=0, MC=0, MB=0, MA=MPI-768, M1=MPI-531, M2=264, S=264, AO=264;

[0112] When X_ MODEL When =3, sequence=1, MD=0, MC=0, MB=0, MA=MPI-768, M1=264, M2=264, S=264, AO=264;

[0113] When X_ MODEL =4, when sequence=1, MD=0, MC=0, MB=MPI-942, MA=MPI-768, M1=264, M2=264, S=264, AO=264;

[0114] When X_ MODEL When sequence = 5, MD = 0, MC = 0, MB = MPI-942, MA = 264, M1 = 264, M2 = 264, S = 264, AO = 264;

[0115] When X_ MODEL =6, sequence=1, MD=0, MC=MPI-1123, MB=MPI-942, MA=264, M1=264, M2=264, S=264, AO=264;

[0116] When X_ MODELWhen sequence = 7, MD = 0, MC = MPI-1123, MB = 264, MA = 264, M1 = 264, M2 = 264, S = 264, AO = 264;

[0117] When X_ MODEL =8, sequence=1, MD=MPI-1304, MC=MPI-1123, MB=264, MA=264, M1=264, M2=264, S=264, AO=264;

[0118] When X_ MODEL =9, when sequence=1, MD=MPI-1304, MC=264, MB=264, MA=264, M1=264, M2=264, S=264, AO=264. Formula 16.

[0119] In this invention, all interpolation methods are linear interpolation.

[0120] In a second aspect, the present invention provides an automatic calculation system for increasing the upper limit of reactor control rod assembly for a third-generation pressurized water reactor nuclear power plant. The automatic calculation system is obtained according to the precise calculation method described in the first aspect. The automatic calculation system includes a nuclear design data input module, a low-power physics test data input module, a real-time demand input module, a calculation module, and a result display module.

[0121] Preferably, the data input by the real-time demand input module includes set arbitrary fuel consumption, arbitrary power, arbitrary boron concentration, pilot rod sequence value, and single boost Δ power;

[0122] Preferably, the result display module displays the upper limit of MA, MB, MC, MD, and M1.

[0123] In this invention, to more conveniently and automatically calculate the upper limit of control rod assembly lift, an automatic calculation system was developed based on precise calculation methods. This overcomes the shortcomings of manual calculation, such as long calculation time (approximately one hour per calculation) and high error rate, further ensuring the accurate control of the reactor control rod assembly lift upper limit by nuclear power plant operators. The automatic calculation system has undergone repeated debugging and practical verification, proving its practicality as a rapid calculation system for the control rod assembly lift upper limit.

[0124] In this case, the single-time boost Δ power is generally set to 0, and the current power + single-time boost Δ power = input power during calculation.

[0125] In this invention, the function of an automatic calculation system can be realized through computer programming based on the precise calculation method described in the first aspect.

[0126] Compared with the prior art, the present application has the following beneficial effects:

[0127] (1) The precise calculation method considers and contains the influence of the difference between the predicted calculation and the actual reactor operation on the control rod group lifting upper limit, so that the control rod lifting upper limit is more accurate.

[0128] (2) The precise calculation method can calculate the reactor control rod group lifting upper limit under the conditions of any burnup, any power and any boron concentration, and the calculation range and accuracy cover all stages of reactor power operation, the calculation speed is fast, the accuracy is high, and the conversion of related boron concentration values and rod position values is not required manually, thereby saving working time and meeting the requirements of nuclear power plant operators for simple and easy-to-read control rod group lifting upper limit.

[0129] (3) The automatic calculation system realizes the control rod lifting upper limit display function, which plays an excellent auxiliary effect on the operation of the control rod for the nuclear power plant operators. BRIEF DESCRIPTION OF DRAWINGS

[0130] Figure 1 is a calculation flowchart of a reactor control rod group lifting upper limit automatic calculation system for a third-generation pressurized water reactor nuclear power plant provided by embodiment 2 of the present application. DETAILED DESCRIPTION

[0131] To better illustrate the present application and facilitate understanding of the technical solutions of the present application, the present application will be further described in detail below. However, the following embodiments are only simple examples of the present application and do not represent or limit the protection scope of the present application, and the protection scope of the present application is subject to the claims.

[0132] The following are typical but non-limiting embodiments of the present application:

[0133] Embodiment 1:

[0134] The present embodiment provides a precise calculation method for the reactor control rod group lifting upper limit of a third-generation pressurized water reactor nuclear power plant, and the precise calculation method comprises:

[0135] According to the requirements, any burnup is selected as 700MWd / tU, any boron concentration is selected as 1900ppm, any power is selected as 10%, and the pilot rod group is MA.

[0136] (1) The data provided by the low-power physical test results are shown in Table 1.

[0137] Table 1

[0138]

[0139] The related data of the nuclear design document is shown in Table 2.

[0140] Table 2

[0141] End boron concentration predicted value CB predicted ]] 2002 Boron 10 abundance prediction during low power physics tests 19.9％ Isothermal temperature coefficient prediction value ITC predicted ]] 1.5

[0142] The results calculated according to the formula 1 to formula 10 are shown in Table 3.

[0143] Table 3

[0144]

[0145] (2) Firstly, according to the nuclear design unit, a maximum boron concentration table corresponding to the predicted control rod group lifting upper limit under 8 typical burnups (a single table contains 11 typical power levels and 18 typical total rod position conditions) (i.e. an initial table) is provided, and a maximum boron concentration table (RWL predicted ) corresponding to the predicted control rod lifting upper limit under the burnup of 700 MWd / tU (containing 11 typical power levels and 18 typical total rod position conditions) is obtained by interpolation algorithm (formula 11), and is recorded as Table A.

[0146] Table A

[0147] MPI 0% RTP 10% RTP 20% RTP 30% RTP 40% RTP 50% RTP 60% RTP 70% RTP 80% RTP 90% RTP 100% RTP 1575 1797.4 1839.6 1880.3 1920.8 1960.3 2000.5 1979.1 1960.8 1944.0 1931.8 1921.5 1485 1801.7 1843.5 1884.1 1923.7 1962.9 2003.2 1981.8 1961.7 1945.0 1931.5 1920.4 1394 1830.3 1870.5 1909.1 1948.1 1987.6 2027.1 2004.7 1983.6 1967.2 1952.0 1940.6 1304 1845.3 1887.1 1927.6 1967.4 2006.9 2046.9 2024.9 2005.6 1988.8 1975.1 1963.3 1213 1836.2 1877.9 1918.3 1957.5 1997.8 2037.6 2016.2 1996.9 1980.1 1966.1 1955.2 1123 1835.4 1877.8 1919.1 1959.9 1999.9 2040.6 2019.8 2001.0 1984.2 1970.2 1960.8 1032 1833.9 1876.2 1917.5 1958.3 1998.6 2039.4 2018.6 1999.8 1984.0 1970.9 1961.4 942 1844.8 1887.5 1928.9 1969.8 2010.4 2051.5 2029.9 2010.7 1995.2 1982.1 1972.0 898 1859.2 1900.9 1941.8 1982.2 2022.3 2063.2 2041.5 2021.9 2004.8 1991.4 1980.4 898 1859.2 1900.9 1941.8 1982.2 2022.3 2063.2 2041.5 2021.9 2004.8 1991.4 1980.4 851 1880.5 1921.6 1962.0 2002.4 2042.7 2083.6 2061.5 2041.5 2023.6 2009.4 1998.9 780 1908.3 1950.3 1991.4 2032.2 2073.4 2114.6 2092.8 2073.5 2057.4 2043.9 2033.7 768 1910.3 1952.7 1993.8 2035.0 2076.2 2117.1 2095.9 2076.3 2060.2 2048.0 2038.5 741 1909.0 1951.4 1982.7 2033.8 2074.5 2115.6 2094.3 2074.5 2058.2 2044.8 2035.5 706 1911.2 1953.4 1994.8 2035.5 2076.1 2116.9 2094.5 2075.4 2058.0 2043.3 2032.9 656 1923.5 1965.1 2005.1 2044.8 2084.4 2123.5 2100.9 2079.4 2061.3 2044.3 2032.1 606 1955.5 1995.5 2034.5 2072.3 2111.9 2151.1 2126.9 2104.8 2086.0 2069.1 2055.6 568 1989.5 2028.8 2068.1 2107.2 2146.6 2186.6 2162.8 2140.5 2120.7 2104.6 2092.8 531 2012.4 2054.3 2095.6 2136.4 2177.5 22191.0 21965.0 2176.5 2157.9 2144.7 2134.2

[0148] Wherein, MPI represents the total rod position, and RTP represents the power.

[0149] According to the Table A, a maximum boron concentration table (RWL predicted * ) corresponding to the predicted control rod lifting upper limit under the burnup of 700 MWd / tU and the power of 10% (containing 11 typical power levels and 18 typical total rod position conditions) is obtained by interpolation algorithm (formula 12), and is recorded as Table B.

[0150] Table B

[0151]

[0152]

[0153] The Table B is corrected by using the related maximum boron concentration correction value obtained in the step (1) (formula 13), and a maximum boron concentration table corresponding to the actual control rod lifting upper limit under the burnup of 700 MWd / tU and the power of 10% (containing 18 typical total rod position conditions) is obtained, and is recorded as Table C.

[0154] RWL Final = (RWL predicted * -CF ITC ×ΔITC Bias )×(19.9% / M B10 ) Formula 13

[0155] Table C

[0156] MPI Actual maximum boron concentration / ppm 1575 1853.67 1485 1857.57 1394 1884.74 1304 1901.43 1213 1892.14 1123 1892.06 1032 1890.47 942 1901.83 898 1915.26 851 1936.08 780 1964.99 768 1967.38 741 1966.09 706 1968.10 656 1979.84 606 2010.35 568 2043.86 531 2069.47

[0157] According to the Table C, the total rod worth table under the condition of burnup 700 MWd / tU, power 10%, boron concentration 1900 ppm is calculated by interpolation method, which is recorded as Table D;

[0158] Table D

[0159] Power / % Burnup / MWd / tU Boron concentration / ppm MPI 10 700 1900 956

[0160] (3) The total rod worth table of step (2) is decomposed to obtain the actual control rod bank lifting upper limit under the condition of burnup 700 MWd / tU, power 10%, boron concentration 1900 ppm;

[0161] According to formula 14, MPI = 956, 949 < MPI ≤ 1032, X_ = 1. MODEL = 4;

[0162] Then the sequence of the leading rod bank is determined by formula 15. Since the leading rod bank is the MA rod bank, it is judged that the sequence value of the leading rod bank sequence is 1.

[0163] Formula 16 is arranged as Table E, and according to formula 16, the final actual control rod bank lifting upper limit can be obtained;

[0164] Table E

[0165]

[0166]

[0167] From Table E, the final result is obtained, that is, under the condition of burnup 700 MWd / tU, power 10%, boron concentration 1900 ppm, the actual lifting upper limit of each control rod bank is respectively:

[0168] MD = 0, MC = 0, MB = MPI-942 = 14, MA = MPI-768 = 188, M1 = 264, M2 = 264, S = 264, AO = 264.

[0169] Example 2:

[0170] The embodiment provides an automatic calculation system for lifting upper limit of a reactor control rod bank of a third-generation pressurized water reactor nuclear power plant, and the automatic calculation system comprises a nuclear design data input module, a low-power physical test data input module, a real-time demand input module, a calculation module and a result display module.

[0171] The data inputted by the real-time demand input module includes set arbitrary burnup, arbitrary power, arbitrary boron concentration, leader rod sequence value and single-time boost Δpower;

[0172] The result display module displays the boost upper limit of MA, MB, MC, MD and M1.

[0173] The automatic calculation system calculation flow chart is shown in Figure 1

[0174] As can be seen from the above embodiments, the precise calculation method considers and contains the influence of the difference between the prediction calculation and the actual reactor operation on the control rod group boost upper limit, so that the control rod boost upper limit is more accurate; and the control rod group boost upper limit under the condition of arbitrary burnup, arbitrary power and arbitrary boron concentration can be calculated, the calculation range and accuracy cover each stage of the reactor power operation, the calculation speed is fast, the accuracy is high, and the conversion of the related boron concentration value and the rod position value is not required by manual, the working time is saved, the requirements of the nuclear power plant operators for the control rod group boost upper limit are met, the operation of the control rod is assisted, and the excellent auxiliary effect is achieved.

[0175] The applicant declares that the detailed method of the present application is illustrated by the above embodiments, but the present application is not limited to the above detailed method, that is, it does not mean that the present application must rely on the above detailed method to be implemented. It should be understood by those skilled in the art that any improvement of the present application, equivalent replacement and auxiliary operation of the operation of the present application, addition of specific mode selection, etc. fall within the protection scope and disclosure scope of the present application.​

Claims

1. A method for precise calculation of the upper limit of the reactor control rod bank group of a third generation pressurized water reactor nuclear power plant, characterized in that, The precise calculation method comprises the following steps: (1) obtaining the difference between the predicted calculation and the actual reactor operation through theoretical calculation of the low-power physical test results and the related data of the nuclear design file, and then calculating the related maximum boron concentration correction value; (2) obtaining an initial table of the maximum boron concentration corresponding to the predicted control rod group lifting upper limit under 8 typical burnups from the nuclear design unit; According to the initial table, an arbitrary burnup is calculated by an interpolation algorithm to obtain a maximum boron concentration table corresponding to the predicted control rod lifting upper limit under the arbitrary burnup, which is denoted as table A; According to the table A, an arbitrary burnup is calculated by an interpolation algorithm to obtain a maximum boron concentration table corresponding to the predicted control rod lifting upper limit under the arbitrary burnup and the arbitrary power, which is denoted as table B; The table B is corrected by using the related maximum boron concentration correction value obtained in step (1) to obtain a maximum boron concentration table corresponding to the actual control rod lifting upper limit under the arbitrary burnup and the arbitrary power, which is denoted as table C; According to the table C, an arbitrary burnup, an arbitrary power and an arbitrary boron concentration are calculated by an interpolation algorithm to obtain a total rod position table under the arbitrary burnup, the arbitrary power and the arbitrary boron concentration; (3) decomposing and calculating the total rod position table in step (2) to obtain the lifting upper limit of the actual control rod group under the arbitrary burnup, the arbitrary power and the arbitrary boron concentration; The reactor control rod group comprises: an axial power distribution control rod group, denoted as AO rod group; a shutdown control rod group, denoted as S rod group; a temperature and power control rod group, denoted as M rod group; the M rod group comprises M1, M2, MA, MB, MC and MD six sub-rod groups.

2. The method of claim 1, wherein, The low power physics test results of step (1) include isothermal temperature coefficient measurements, denoted as ITC measured ; average boron concentration obtained by chemical sampling during isothermal temperature coefficient measurements, denoted as CB measured ; boron 10 abundance measured during the low power physics test, denoted as M B10 ; average of the average temperature during the moderator temperature ramp-up and the average temperature during the temperature ramp-down during isothermal temperature coefficient measurements, denoted as T mod，measurement .

3. The method of claim 2, wherein, The nuclear design file related data described in step (1) includes an end-of-boron concentration prediction value, denoted as CB predicted ; a boron-10 enrichment prediction value during low-power physical testing, which has a default value of 19.9%; and an isothermal temperature coefficient prediction value, denoted as ITC predicted .

4. The method of claim 3, wherein, The specific method of step (1) comprises: The average boron concentration deviation between the predicted and actual is calculated by formula 1, denoted as ΔCB: ACB = CB predicted - CB measured x (M B10 / 19.9%) Equation 1 By formula 2, the boron concentration deviation is judged to determine the deviation coefficient of the isothermal temperature coefficient of the boron concentration deviation, denoted as CF CB : When ΔCB > 0, CF CB = 0.0182 pcm / °C / ppm When ΔCB≤0, CF CB = 0.0155 pcm / °C / ppm Equation 2 The boron concentration dependent isothermal temperature coefficient deviation, denoted as ΔITC, is calculated by Equation 3 CB : ΔITC CB = ΔCB x CF CB Equation 3 The moderator temperature deviation, denoted as ΔT, is calculated by equation 4 mod : ΔT mod = 291.7°C - T mod,measurement Equation 4 By formula 5, the moderator temperature deviation revision isothermal temperature coefficient deviation coefficient is calculated, denoted as CF Tmod : When ΔT mod > 0, CF Tmod = -0.2111 pcm / °C / °C When ΔT mod ≤ 0, CF Tmod = -0.2409 pcm / °C / °C Equation 5 The moderator temperature dependent isothermal temperature coefficient bias, denoted as ΔITC, is calculated by equation 6 Tmod : ΔITC Tmod = ΔT mod x CF Tmod Equation 6 The isothermal temperature coefficient revised value is calculated by formula 7, denoted as ITC adjusted : ITC adjusted = ITC measured + ΔITC CB + ΔITC Tmod Equation 7 The isothermal temperature coefficient deviation, denoted as ΔITC, is calculated by Equation 8 Bias : ΔITC Bias = ITC adjusted - ITC predicted Equation 8 By formula 9, the maximum boron concentration coefficient corresponding to the upper limit of the isothermal temperature coefficient bias revision is calculated, denoted as CF ITC : When ΔITC Bias > 0, CF ITC = 64.60 ppm / pcm / °C When ΔITC Bias ≤ 0, CF ITC = 55.01 ppm / pcm / °C Equation 9 The difference between the predicted calculation and the actual reactor operation is obtained by formula 10, and then the related maximum boron concentration correction value is calculated: Correlation maximum boron concentration correction value = CF ITC ×△ITC Bias Formula 10.

5. The method of claim 1-4, wherein, According to the initial table, by formula 11, the table A in step (2) is obtained; wherein, the maximum boron concentration value corresponding to the upper limit of the control rod bank lifting under the arbitrary fuel consumption is denoted as RWL predicted : when the arbitrary burnup < 150 MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the predicted upper limit of the control rod bank lift when the arbitrary burnup = 150 MWd / tU. RWL = 0.5 when 150 MWd / tU < burnup < 500 MWd / tU predicted RWL = 0.5 when 150 MWd / tU < burnup < 500 MWd / tU predicted the result of linear interpolation; When 500 MWd / tU < the arbitrary burnup < 1000 MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the upper limit of the predicted control rod bank lifting at the burnup of 500 MWd / tU and 1000 MWd / tU in the table, RWL at the same power and the same total rod position predicted The result of linear interpolation is carried out. When 1000MWd / tU < any fuel consumption ≤ 2000MWd / tU, RWL predicted The table shows the maximum boron concentration values ​​corresponding to the upper limit of the predictive control rod assembly for fuel consumption of 1000MWd / tU and 2000MWd / tU, and the RWL values ​​for the same power and total number of rods. predicted The result of linear interpolation; When 2000MWd / tU < any fuel consumption ≤ 3000MWd / tU, RWL predicted The table shows the maximum boron concentration values ​​corresponding to the upper limit of the predictive control rod assembly for fuel consumption of 2000MWd / tU and 3000MWd / tU, and the RWL values ​​for the same power and total number of rods. predicted The result of linear interpolation; when 3000 MWd / tU < the arbitrary burnup < 4000 MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the upper limit of the predicted control rod bank lifting at the burnup of 3000 MWd / tU and 4000 MWd / tU in the table, RWL at the same power and the same total rod position predicted the result of linear interpolation When 4000 MWd / tU < the arbitrary burnup ≤ 5000 MWd / tU, RWL predicted = the maximum boron concentration value corresponding to the upper limit of the predicted control rod bank lifting at the burnup of 4000 MWd / tU and 5000 MWd / tU in the table, RWL at the same power and the same total rod position predicted The result of linear interpolation is carried out. When 5000MWd / tU < any fuel consumption ≤ 6000MWd / tU, RWL predicted The table shows the maximum boron concentration values ​​corresponding to the upper limit of the predictive control rod assembly for fuel consumption of 5000MWd / tU and 6000MWd / tU, and the RWL values ​​for the same power and total number of rods. predicted The result of linear interpolation; When 6000MWd / tU < any fuel consumption ≤ 7000MWd / tU, RWL predicted The table shows the maximum boron concentration values ​​corresponding to the upper limit of the predictive control rod assembly for fuel consumption of 6000MWd / tU and 7000MWd / tU, and the RWL values ​​for the same power and total number of rods. predicted The result of linear interpolation; When the arbitrary burnup ≥ 7000 MWd / tU, RWL predicted =7000 MWd / tU, the maximum boron concentration value corresponding to the upper limit of the predicted control rod bank lifting formula 11.

6. The method of claim 1-4, wherein, According to the table A, by formula 12, the table B of step (2) is obtained; wherein, the maximum boron concentration value corresponding to the upper limit of the predicted control rod group lifting under the arbitrary fuel consumption and arbitrary power is denoted as RWL predicted * : When 0% < the arbitrary power < 10%, RWL predicted * = 0% and 10% power, the RWL under the same total rod position in the table A predicted The result of linear interpolation; RWL = 10% and 20% power under the table A, same total bar position predicted * RWL = 10% and 20% power under the table A, same total bar position predicted the result of a linear interpolation; When 20% < the arbitrary power < 30%, RWL predicted * = 20% and 30% power, the RWL in the table A under the same total rod worth predicted the result of linear interpolation; When 30% < the arbitrary power < 40%, RWL predicted * = the RWL at the same total rod worth in the table A at 30% and 40% power predicted the result of linear interpolation; When 40% < the arbitrary power < 50%, RWL predicted * = 40% and 50% power, the RWL in the table A under the same total rod worth predicted the result of linear interpolation; RWL = 50% and 60% power under the same total rod worth in Table A predicted * RWL = 50% and 60% power under the same total rod worth in Table A predicted the result of linear interpolation; When 60% < the arbitrary power < 70%, RWL predicted * = 60% and 70% power, the RWL in the table A under the same total rod worth predicted the result of linear interpolation; When 70% < the arbitrary power < 80%, RWL predicted * =70% and 80% power, the RWL in the table A under the same total rod worth predicted the result of linear interpolation; When 80% < the arbitrary power < 90%, RWL predicted * = 80% and 90% power, the RWL in the table A under the same total rod worth predicted the result of linear interpolation; RWL = 100% when 90% < arbitrary power < 100% predicted * = 90% and 100% power under the same total bar position in Table A predicted The result of performing a linear interpolation is given by Equation 12.

7. The method of claim 1-4, wherein, The table C is obtained by modifying the table B described in step (2) using the formula 13: wherein the arbitrary fuel consumption, the maximum boron concentration value corresponding to the actual control rod bank upper limit under the arbitrary power, is denoted as RWL Final : RWL Final = (RWL predicted * -CF ITC x ΔITC Bias ) x (19.9% / M B10 ) Equation 13.

8. The method of claim 5, wherein, The total rod position value in the total rod position table in step (2) is rounded.

9. The method of claim 8, wherein, Step (3) said decomposition calculation by formula 14; wherein, the total bar position, recorded as MPI; total bar position interval module value, recorded as X MODEL : When 531 < MPI < 768, X MODEL = 1; When 768 < MPI < 780, X MODEL = 2; When 780 < MPI < 949, X MODEL = 3; When 949 < MPI < 1032, X MODEL = 4; When 1032 < MPI < 1130, X MODEL = 5; When 1130 < MPI < 1213, X MODEL = 6; When 1213 < MPI < 1311, X MODEL = 7; When 1311 < MPI < 1394, X MODEL = 8; When 1394 < MPI < 1575, X MODEL = 9 Equation 14.

10. The method of claim 9, wherein, The decomposition calculation in step (3) further comprises determining the sequence of the leading rod group by formula 15: When the leading rod group of the reactor is the MA rod group, the sequence value of the leading rod group is 1; When the leading rod group of the reactor is the MD rod group, the sequence value of the leading rod group is 2 formula 15.

11. The method of claim 10, wherein, The lifting upper limits of the AO rod group, the S rod group and the M rod group are calculated according to formula 16: When X MODEL = 1, sequence = 2, MA = 0, MB = 0, MC = 0, MD = 0, M1 = MPI-531, M2 = 264, S = 264, AO = 264; When X MODEL = 2, sequence = 2, MA= 0, MB= 0, MC= 0, MD= MPI-768, M1= MPI-531, M2= 264, S= 264, AO= 264; When X MODEL = 3, sequence = 2, MA= 0, MB= 0, MC= 0, MD= MPI-768, M1= 264, M2= 264, S= 264, AO= 264; When X MODEL = 4, sequence = 2, MA= 0, MB= 0, MC= MPI-942, MD= MPI-768, M1= 264, M2= 264, S= 264, AO= 264; When X MODEL = 5, sequence = 2, MA= 0, MB= 0, MC= MPI-942, MD= 264, M1= 264, M2= 264, S= 264, AO= 264; When X MODEL = 6, sequence = 2, MA = 0, MB = MPI-1123, MC = MPI-942, MD = 264, M1 = 264, M2 = 264, S = 264, AO = 264; When X MODEL = 7, sequence = 2, MA = 0, MB = MPI-1123, MC = 264, MD = 264, M1 = 264, M2 = 264, S = 264, AO = 264; When X MODEL = 8, sequence = 2, MA= MPI-1304, MB= MPI-1123, MC= 264, MD= 264, M1= 264, M2= 264, S= 264, AO= 264; When X MODEL = 9, sequence = 2, MA= MPl-1304, MB= 264, MC= 264, MD= 264, Ml= 264, M2= 264, S= 264, AO= 264; When X MODEL = 1, sequence = 1, MD = 0, MC = 0, MB = 0, MA = 0, M1 = MPI-531, M2 = 264, S = 264, AO = 264; When X MODEL = 2, sequence = 1, MD = 0, MC = 0, MB = 0, MA = MPI-768, M1 = MPI-531, M2 = 264, S = 264, AO = 264; When X MODEL = 3, sequence = 1, MD = 0, MC = 0, MB = 0, MA = MPI-768, M1 = 264, M2 = 264, S = 264, AO = 264; When X MODEL = 4, sequence = 1, MD = 0, MC = 0, MB = MPI-942, MA = MPI-768, M1 = 264, M2 = 264, S = 264, AO = 264; When X MODEL = 5, sequence = 1, MD = 0, MC = 0, MB = MPI-942, MA = 264, M1 = 264, M2 = 264, S = 264, AO = 264; When X MODEL = 6, sequence = 1, MD = 0, MC = MPI-1123, MB = MPI-942, MA = 264, M1 = 264, M2 = 264, S = 264, AO = 264; When X MODEL = 7, sequence = 1, MD = 0, MC = MPI-1123, MB = 264, MA = 264, M1 = 264, M2 = 264, S = 264, AO = 264; When X MODEL = 8, sequence = 1, MD = MPI-1304, MC = MPI-1123, MB = 264, MA = 264, M1 = 264, M2 = 264, S = 264, AO = 264; When X MODEL = 9, sequence = 1, MD = MPI-1304, MC = 264, MB = 264, MA = 264, M1 = 264, M2 = 264, S = 264, AO = 264 Equation 16.

12. An automatic calculation system for the upper limit of the reactor control rod bank group of a third generation pressurized water reactor nuclear power plant, characterized by, The automatic calculation system is obtained according to the precise calculation method in any one of claims 1-11, and the automatic calculation system comprises a nuclear design data input module, a low-power physical test data input module, a real-time demand input module, a calculation module and a result display module.

13. The automated computing system of claim 12 wherein: The data input by the real-time demand input module comprises a set arbitrary burnup, an arbitrary power, an arbitrary boron concentration, a leading rod sequence value and a single lifting Δ power.

14. The automated computing system of claim 12 wherein: The result display module displays the lifting upper limits of MA, MB, MC, MD and M1.

Images