Rod swap system and method for reactor of nuclear power plant

Abstract

A rod swap system and method for a reactor of a nuclear power plant. The rod swap system for a reactor of a nuclear power plant comprises: a power determination unit (1), which is used for determining

Description

[0001] The present invention relates to the field of nuclear power instrumentation and control technology, and particularly to a system and method for rod position swap in a nuclear power plant reactor. DESCRIPTION OF RELATED ART

[0002] The power coordination control between the nuclear reactor and the turbine-generator unit in a nuclear power plant is extremely important. It involves the conversion of nuclear energy to electrical energy as well as the energy balance with the electrical grid. Only safe and reliable reactor-unit matching can ensure the safe and economical operation of the nuclear power plant.

[0003] Currently, some nuclear power plants employ the MODE-G control system for reactor regulation, which coordinates reactivity and unit power by adjusting the temperature control rod group, power control rod group, and boron concentration. The power control rod group compensates for large-scale power variations (coarse adjustment), while the temperature control rod group controls the primary loop average temperature (fine adjustment). Boron adjustment is used to compensate for slow reactivity changes caused by burnup and large-scale reactivity variations due to xenon effects. However, the MODE-G mode requires operators to manually adjust boron multiple times a day to compensate for slow reactivity changes from burnup, leading to drawbacks such as high wastewater generation, low automation levels, and poor flexibility. Additionally, prolonged setback of the T-rod group into the core exacerbates the fuel shadowing effect, thereby affecting the radial power peaking factor. Furthermore, the influence of primary loop power on rod position swap operations is overlooked, introducing certain safety risks during rod position swap. Currently, nuclear power plants lack a rod position swap method that can mitigate the fuel shadowing effect while enabling automated rod position swap. BRIEF SUMMARY OF THE INVENTION

[0004] The technical problem to be solved by the present invention is to provide a system and method for rod position swap in a nuclear power plant reactor.

[0005] The technical solution adopted by the present invention to solve the technical problem is: constructing a system for rod position swap in a nuclear power plant reactor, comprising:

[0006] a power determination unit, configured to determine whether the primary loop power is stable and generate a determination result for indicating whether the primary loop power is stable;

[0007] a power fluctuation prevention unit, configured to monitor the fluctuation state of the primary loop power in real time; and

[0008] a rod position swap execution unit, configured to sequentially perform rod position swap processing on the first and second T-rod groups included in each temperature rod group sequentially according to the fluctuation state after determining that the primary loop power is stable.

[0009] Preferably, the system for rod position swap in a nuclear power plant reactor further comprises:

[0010] a sequence control unit, configured to send an execution instruction to the rod position swap execution unit according to a preset rule to control each temperature rod group to perform rod position swap processing, so that only after the current temperature rod group completes the rod position swap. The temperature rod groups that have not completed the swap will be controlled to perform the rod position swap processing.

[0011] Preferably, the system for rod position swap in a nuclear power plant reactor further comprises: a memory unit, configured to record the initial rod positions corresponding to all T-rod groups before the rod position swap process is performed;

[0012] The rod position swap execution unit includes a control rod actuation mechanism for controlling the withdrawal or setback of T-rod group according to a withdrawal / setback instruction, and multiple rod-group pair execution units, each corresponding to one of the temperature rod groups;

[0013] wherein each of the rod-group pair execution units comprises:

[0014] a start-stop control module for acquiring a pause instruction, a termination instruction, and an execution instruction of the corresponding temperature rod group to generate a start-stop instruction;

[0015] a first rod group execution module for acquiring the start-stop instruction, the real-time rod position of the first T-rod group and the initial rod position of the second T-rod group of the corresponding temperature rod group to generate a withdrawal / setback instruction for the first T-rod group; and

[0016] a second rod group execution module for acquiring the start-stop instruction, the real-time rod position of the second T-rod group and the initial rod position of the first T-rod group of the corresponding temperature rod group, to generate a withdrawal / setback instruction for the second T-rod group.

[0017] Preferably, the first and second rod group execution modules respectively include:

[0018] A comparison module, wherein its second input end acquires the real-time rod position of the corresponding T-rod group, its first input end acquires the initial rod position of the paired other T-rod group, its first output end outputs a setback signal of the corresponding T-rod group, its second output end outputs a completion indication signal indicating whether the corresponding T-rod group has completed a withdrawal or setback action, and its third output end outputs a withdrawal signal of the corresponding T-rod group;

[0019] A first AND gate, wherein each of its input ends respectively acquires a unlock setback signal, the start-stop instruction, and the setback signal, and outputs a setback instruction of the corresponding T-rod group through its output end; and

[0020] A second AND gate, wherein each of its input ends respectively acquires a unlock withdrawal signal, the start-stop instruction, and the withdrawal signal, and outputs a withdrawal instruction of the corresponding T-rod group through its output end.

[0021] Preferably, the start-stop control module comprises:

[0022] a first RS flip-flop, wherein its R-end receives the execution instruction, and its S-end receives the termination instruction;

[0023] a first OR gate, wherein one input end receives the pause instruction, and the other input end is connected to the output end of the first RS flip-flop; and

[0024] a first NOT gate, wherein its input end is connected to the output end of the first OR gate, and its output end outputs the start-stop instruction.

[0025] Preferably, the power fluctuation prevention unit comprises:

[0026] A subtractor module, wherein a first end thereof acquires the primary loop average temperature set value, and a second end thereof acquires the primary loop average temperature measured value, configured to calculate a difference value between the primary loop average temperature set value and the primary loop average temperature measured value;

[0027] A selection control module, configured to acquire completion indication signals of each T-rod group and execution instructions of each temperature rod group to generate a selection control signal;

[0028] A selection module, wherein a first input end thereof receives the difference value, and a selection end thereof receives the selection control signal, so as to determine whether to output the difference value according to the selection control signal;

[0029] A first limit comparison module, configured to output a unlock setback signal that can control a T-rod group performing rod position swap that need to setback rod position to pause rod setback when the difference value is greater than a first limit; and

[0030] A second limit comparison module, configured to output a unlock withdrawal signal that can control a T-rod group performing rod position swap that need to withdrawal rod position to pause rod withdrawal when the difference value is less than a second limit.

[0031] Preferably, the selection control module comprises a second OR gate and a plurality of trigger modules corresponding one-to-one to each temperature rod group;

[0032] wherein each trigger module comprises:

[0033] a third OR gate, with its first and second input ends respectively acquiring completion indication signals from two T-rod groups in the corresponding temperature rod group;

[0034] a fourth AND gate, with its first input end connected to the output end of the third OR gate and its second input end acquiring an execution instruction of the corresponding temperature rod group;

[0035] a second RS flip-flop, with its R-end connected to the output end of the fourth AND gate and its S-end acquiring the execution instruction of the corresponding temperature rod group;

[0036] the input ends of the second OR gate are respectively connected to the output ends of the second RS flip-flops included in each trigger module, and the output end of the second OR gate outputs the selection control signal.

[0037] Preferably, the power determination unit comprises:

[0038] a temperature measurement module for acquiring the primary loop average temperature measured value;

[0039] a latch module, with its latch end configured to receive an absolute value comparison result, and its input end connected to the temperature measurement module to acquire the primary loop average temperature measured value, for outputting a latched reference value based on the absolute value comparison result;

[0040] an absolute value comparison module, with its first end acquiring the primary loop average temperature measured value, its second end connected to the output end of the latch module to acquire the latched reference value, and its third end acquiring a first preset value, for determining whether an absolute deviation between the primary loop average temperature measured value and the latched reference value is greater than the first preset value, and outputting the absolute value comparison result via its output end;

[0041] a fifth NOT gate, with its input end connected to the output end of the absolute value comparison module to acquire the comparison signal, thereby performing a NOT operation on the comparison signal; and

[0042] a pre-delay module, with its input end connected to the output end of the fifth NOT gate, for outputting the determination result via its output end after delaying for a first preset time.

[0043] The present invention also constructs a method for rod position swap in a nuclear power plant reactor comprising following steps:

[0044] S10, determining whether the primary loop power is stable, and if so, proceeding to the next step;

[0045] S20, monitoring the fluctuation state of the primary loop power in real time;

[0046] S30, performing rod position swap processing sequentially on the two T-rod groups included in each temperature rod group according to the fluctuation state.

[0047] Preferably, in the S30, it further includes: only after the current temperature rod group completes the rod position swap, allowing the temperature rod groups that have not completed the rod position swap to perform the rod position swap processing.

[0048] Preferably, in the S10, the step of determining whether the primary loop power is stable includes:

[0049] Within a first preset time, determining whether the absolute deviation between the primary loop average temperature measured value and the latched reference value is less than a first preset value. If yes, the primary loop power is determined to be stable; otherwise, it is determined to be unstable.

[0050] Preferably, the first preset time is 200 seconds; and / or the first preset value is 0.4°C.

[0051] Preferably, before the S30, it further includes: recording the initial rod positions corresponding to all T-rod groups before performing the rod position swap process;

[0052] In the S30, the rod position swap process includes:

[0053] When a pause instruction input by a user is received, controlling all T-rod groups to stop at their current positions;

[0054] When no pause instruction input by a user is received, controlling the T-rod group that need to withdrawal rod position and the T-rod group that need to setback rod position to withdrawal and setback their rod positions at the same speed, respectively, until the position of the T-rod group that need to withdrawal reach the initial rod position of the T-rod group that need to setback, and the position of the T-rod group that need to setback descend to the initial rod position of the T-rod group that need to withdraw.

[0055] Preferably, the step S30 includes:

[0056] S301: Monitoring the primary loop average temperature measured value in real time;

[0057] S302: If the difference value between the primary loop average temperature set value and the primary loop average temperature measured value exceeds a first limit, controlling the T-rod group performing rod position swap that requires setback to pause the setback;

[0058] S303: If the difference value between the primary loop average temperature set value and the primary loop average temperature measured value is below a second limit, controlling the T-rod group performing rod position swap that need to withdrawal to pause the withdraw.

[0059] Preferably, the first limit is 0.3°C, and the second limit is -0.3°C.

[0060] By implementing the technical solution of the present invention, the power determination unit generates a determination result characterizing whether the primary loop power is stable, and the power fluctuation prevention unit monitors the fluctuation state of the primary loop power in real time. Finally, after the rod position swap execution unit confirms the stability of the primary loop power, it performs rod position swap on the first and second T-rod groups included in each temperature rod group sequentially based on the fluctuation state. The implementation of the present invention enables efficient, stable, and reliable automatic rod position swap, overcoming issues such as high wastewater generation, low automation, poor flexibility, and severe shadow effects, significantly reducing the workload of operators and minimizing the risk of human errors. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0061] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0062] FIG. 1 is a schematic structural diagram of a system for rod position swap in a nuclear power plant reactor according to some embodiments of the present invention;

[0063] FIG. 2 is a schematic structural diagram of a rod position swap execution unit according to some embodiments of the present invention;

[0064] FIG. 3 is a schematic structural diagram of a power fluctuation prevention unit according to some embodiments of the present invention;

[0065] FIG. 4 is a schematic structural diagram of a power determination unit according to some embodiments of the present invention;

[0066] FIG. 5 is a schematic flowchart of a method for rod position swap in a nuclear power plant reactor according to some embodiments of the present invention;

[0067] FIG. 6 is a schematic flowchart of step S30 in the method for rod position swap in a nuclear power plant reactor according to some embodiments of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0068] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, the specific embodiments of the invention are described in detail below with reference to the accompanying drawings.

[0069] It should be noted that the flowcharts shown in the drawings are for illustrative purposes only and do not necessarily include all content and operations / steps, nor must they be executed in the described order. For example, some operations / steps may be further broken down, while others may be combined or partially combined. Therefore, the actual execution sequence may vary depending on specific circumstances.

[0070] The block diagrams in the drawings represent functional entities only and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software, in one or more hardware modules or integrated circuits, or across different networks and / or processor devices and / or microcontroller devices.

[0071] Refer to FIG. 1, which is a schematic structural diagram of a system for rod position swap in a nuclear power plant reactor according to some embodiments of the present invention. The system for rod position swap in a nuclear power plant reactor is used to automatically and periodically swap the rod positions of first and second T-rod groups with different rod positions within the core under the state of primary loop power temperature, thereby improving unit automation and reliability. As shown in FIG. 1, the system includes: a power determination unit 1, a power fluctuation prevention unit 2, and a rod position swap execution unit 3.

[0072] The power determination unit 1 is configured to determine whether the primary loop power is stable and generate a determination result indicating whether the primary loop power is stable.

[0073] The power fluctuation prevention unit 2 is configured to monitor the fluctuation state of the primary loop power in real time.

[0074] The rod position swap execution unit 3 is configured to sequentially perform rod position swap processing on the first and second T-rod groups included in each temperature rod group according to the fluctuation state after determining that the primary loop power is stable.

[0075] It should be noted that the purpose of performing the rod position swap processing is to replace the rod position of the first T-rod group with the initial rod position of the second T-rod group and replace the rod position of the second T-rod group with the initial rod position of the first T-rod group.

[0076] In this embodiment, the power determination unit generates a determination result indicating whether the primary loop power is stable, and the power fluctuation prevention unit monitors the fluctuation state of the primary loop power in real time. Finally, after the rod position swap execution unit determines that the primary loop power is stable, it sequentially performs rod position swap processing on the first and second T-rod groups included in each temperature rod group according to the fluctuation state. The implementation of the present invention can efficiently, stably, and reliably automate the rod position swap process, overcoming defects such as high wastewater generation, low automation levels, poor flexibility, and severe shadow effects, significantly reducing operator workload and minimizing human error risks.

[0077] To ensure the stability and safety of the core during the entire rod position swap process, in some embodiments, as shown in FIG. 1, the system for rod position swap in a nuclear power plant reactor further includes a sequence control unit 4.

[0078] The sequence control unit 4 is configured to send an execution instruction to the rod position swap execution unit 3 according to a preset pattern, controlling each temperature rod group to perform rod position swap. It ensures that only after the current temperature rod group completes its rod position swap, the system will control the remaining temperature rod group to perform rod position swap, thereby maintaining core stability and safety throughout the process.

[0079] In some embodiments, as shown in FIG. 1, the system for rod position swap in a nuclear power plant reactor also includes a memory unit 5. The memory unit 5 is configured to record the initial rod positions corresponding to all T-rod groups before the rod position swap process.

[0080] Furthermore, as shown in FIG.2, the rod position swap execution unit 3 includes a control rod actuation mechanism 31 for withdrawal or setback T-rod group based on a withdrawal / setback instruction, and multiple rod-group pair execution units, each corresponding to a temperature rod group. Each rod-group pair execution unit includes a start-stop control module 321, a first rod group execution module 322, and a second rod group execution module 323.

[0081] The start-stop control module 321 is configured to receive a pause instruction, a termination instruction, and an execution instruction for the corresponding temperature rod group to generate a start-stop instruction.

[0082] The first rod group execution module 322 is configured to receive the start-stop instruction, along with the real-time rod position of the first T-rod group and the initial rod position of the second T-rod group of the corresponding temperature rod group, to generate a withdrawal / setback instruction for the first T-rod group.

[0083] The second rod group execution module 323 is configured to receive the start-stop instruction, along with the real-time rod position of the second T-rod group and the initial rod position of the first T-rod group of the corresponding temperature rod group, to generate a withdrawal / setback instruction for the second T-rod group.

[0084] In some embodiments, as shown in FIG.2, the first and second rod group execution modules each include a comparison module 3221, a first AND gate 3222, and a second AND gate 3223.

[0085] The second input end of the comparison module 3221 acquires the real-time rod position of the corresponding T-rod group, while the first input end of the comparison module 3221 acquires the initial rod position of the other paired T-rod group. The first output end of the comparison module 3221 outputs the setback signal of the corresponding T-rod group, the second output end outputs a completion indication signal indicating whether the withdrawal or setback action of the corresponding T-rod group is completed, and the third output end outputs the withdrawal signal of the corresponding T-rod group.

[0086] The input ends of the first AND gate 3222 respectively acquire the unlock setback signal, the start-stop instruction, and the setback signal, and the output end of the first AND gate 3222 outputs the setback instruction of the corresponding T-rod group.

[0087] The input ends of the second AND gate 3223 respectively acquire the unlock withdrawal signal, the start-stop instruction, and the withdrawal signal, and the output end of the second AND gate 3223 outputs the withdrawal instruction of the corresponding T-rod group.

[0088] In some embodiments, as shown in FIG.2, the start-stop control module 321 includes a first RS flip-flop 3211, a first OR gate 3212, and a first NOT gate 3213.

[0089] The R-end of the first RS flip-flop 3211 acquires the execution instruction, and the S-end acquires the termination instruction.

[0090] One input end of the first OR gate 3212 acquires the pause instruction, and the other input end is connected to the output end of the first RS flip-flop 3211.

[0091] The input end of the first NOT gate 3213 is connected to the output end of the first OR gate 3212, and the start-stop instruction is output through the output end of the first NOT gate 3213.

[0092] In the embodiment shown in FIG.2, the rod position swap execution unit 3 includes two rod-group pair execution units. It is understandable that the first rod-group pair execution unit is related to the withdrawal and setback of the first T-rod group Tia and the second T-rod group T2a, while the second rod-group pair execution unit is related to the withdrawal and setback of the first T-rod group Tib and the second T-rod group T2b. Taking the second rod-group pair execution unit as an example, the working principle of the rod position swap execution unit 3 is as follows:

[0093] 1. When the first T-rod group Tib and the second T-rod group T2b need to perform a rod position swap operation, and neither the termination instruction nor the pause instruction is enabled, the Tlb / T2b execution instruction 0010 is at a high level, while the termination instruction and pause instruction are at a low level, causing the start-stop instruction output by the first NOT gate 3213 to be at a high level. If the initial rod position 0006 of Tib is higher than the real-time rod position 0002 of T2b, the setback instruction output by the first output end of the comparison module 3221 included in the first rod group execution module 322 is at a low level, and the withdrawal signal output by the third output end of the comparison module 3221 is at a high level. If the unlock withdrawal signal 0003 is enabled (i.e., at a high level), the withdrawal instruction output by the output end of the second AND gate 3223 is at a high level, thereby causing the control rod actuation mechanism 31 to control the second T-rod group T2b to withdrawal. Conversely, if the initial rod position 0006 of Tib is setback than the real-time rod position 0002 of T2b, the first and third output ends of the comparison module 3221 included in the first rod group execution module 322 output a high level and a low level, respectively. If the unlock setback signal 0004 is enabled, the setback instruction output by the output end of the first AND gate 3222 is at a high level, causing the control rod actuation mechanism 31 to control the second T-rod group T2b to setback. It is understandable that the withdrawal and setback control logic for Tib is similar to the above and will not be elaborated here.

[0094] 2. When the pause instruction is enabled (i.e., at a high level), a high level is input to one input end of the first OR gate 3212, causing the start-stop instruction output by the output end of the first NOT gate 3213 to be at a low level. This signal is input to all first AND gates 3222 and second AND gates 3223 in the rod position swap execution unit 3, making all setback instructions and withdrawal instructions low, thereby preventing all first and second T-rod groups from withdrawal or inserting, i.e., pausing the withdrawal and setback of all T-rod groups.

[0095] 3. When the unlock withdrawal signal 0003 is not enabled (i.e., at a low level), the withdrawal instruction outputs by the output ends of all second AND gates 3223 are at a low level, preventing all first and second T-rod groups from withdrawal. Similarly, when the unlock setback signal 0004 is not enabled, the setback instruction outputs by the output ends of all first AND gates 3222 are at a low level, preventing all first and second T-rod groups from setback.

[0096] In some embodiments, if the initial rod position of the T-rod group obtained at the first input of the comparison module 3221 is the same as the real-time rod position height of the T-rod group obtained at the second input, the second output of the comparison module 3221 outputs a high level, indicating that the corresponding T-rod group has completed its rod position swapping. Taking the second T-rod group T2b as an example, when the real-time rod position of the second T-rod group T2b equals the initial rod position of the first T-rod group Tib, the completion indication signal 0014 of the second T-rod group T2b is at a high level.

[0097] In some embodiments, as shown in FIG.2, the rod position swap execution unit 3 further includes multiple third AND gates 33, each corresponding to a rod-group pair execution unit. The two inputs of the third AND gate 33 are respectively connected to the second outputs of the two comparison modules 3221 within the rod-group pair execution unit. It can be understood that when the rod positions of the two T-rod groups (e.g., Tib and T2b) corresponding to the rod-group pair execution unit have been swapped, the output of the third AND gate 33 will be at a high level. This signal can be used to inform the operator that the rod position swapping of the two T-rod groups in the temperature rod group has been completed.

[0098] In some embodiments, as shown in FIG. 3, the power fluctuation prevention unit 2 includes a subtractor module 21, a selection control module 22, and a selection module 23.

[0099] The first end of the subtractor module 21 acquires a primary loop average temperature set value, and the second end of the subtractor module 21 acquires a primary loop average temperature measured value. The subtractor module 21 is configured to calculate the difference value between the primary loop average temperature set value and the primary loop average temperature measured value.

[00100] The selection control module 22 is configured to acquire the completion indication signals of each T-rod group and the execution instructions of each temperature rod group to generate a selection control signal.

[00101] The first input end of the selection module 23 is connected to the difference value, and the selection end of the selection module 23 is connected to the selection control signal to determine whether to output the difference value based on the selection control signal. Specifically, if the selection control signal is at a high level, the output end of the selection module 23 outputs the difference value; if the selection control signal is at a low level, the output end of the selection module 23 outputs a second preset value (which may be 0, not illustrated) connected to its second input end.

[00102] A first limit comparison module 24 is connected to the output end of the selection module 23. The first limit comparison module 24 is configured to output a unlock setback signal when the difference value exceeds a first limit value, which controls the T-rod group performing rod position swap and that need to rod setback to pause the setback process.

[00103] A second limit comparison module 25 is connected to the output end of the selection module 23. The second limit comparison module 25 is configured to output a unlock withdrawal signal when the difference value is below a second limit value, which controls the T-rod groups performing rod position swap and that need to rod withdrawal to pause the withdrawal process.

[00104] Specifically, as shown in FIG. 3, when the primary loop power experiences an upward fluctuation, the corresponding primary loop average temperature measured value increases, causing the difference value to fall below the second limit value (which may be -0.3°C). In this case, the unlock withdrawal signal 0003 output by the second limit comparison module 25 becomes low level, thereby suspending the withdrawal of all T-rod groups while the setback of T-rod group continues. This results in a decrease in the primary loop average temperature measured value and a corresponding drop in power. As the primary loop average temperature decreases and the difference value no longer falls below the second limit value, the suspended withdrawal of T-rod group resumes. Conversely, when the power experiences a downward fluctuation, the primary loop average temperature measured value decreases, causing the difference value to exceed the first limit value (which may be 0.3°C). In this case, the unlock setback signal 0004 output by the first limit comparison module 24 becomes low level, thereby suspending the setback of all T-rod groups while the withdrawal of T-rod group continues. This leads to an increase in the primary loop average temperature measured value and a corresponding rise in power. As the primary loop average temperature increases and the difference value no longer exceeds the first limit value, the suspended setback of T-rod group resumes.

[00105] In some embodiments, as shown in FIG.3, the first limit comparison module 24 includes an upper limit comparison module and a sixth NOT gate. When the difference value exceeds the first limit, the upper limit comparison module outputs a high level, but under the action of the sixth NOT gate, the signal is converted to a low level, meaning the unlock setback signal 0004 is not enabled. The second limit comparison module 25 includes a setback limit comparison module and a seventh NOT gate. When the difference value is below the second limit, the setback limit comparison module outputs a high level, but under the action of the seventh NOT gate, the signal is converted to a low level, meaning the unlock withdrawal signal 0003 is not enabled.

[00106] In some embodiments, as shown in FIG.3, the selection control module 22 includes a second OR gate 221 and multiple trigger modules 222, each corresponding to a temperature rod group. Each trigger module 222 includes a third OR gate 2221, a fourth AND gate 2222, and a second RS flip-flop 2223.

[00107] The first and second input ends of the third OR gate 2221 receive the completion indication signals from the two T-rod groups in the corresponding temperature rod group, respectively. The first input end of the fourth AND gate 2222 is connected to the output end of the third OR gate 2221, and the second input end of the fourth AND gate 2222 receives the execution instruction of the corresponding temperature rod group. The R-end of the second RS flip-flop 2223 is connected to the output end of the fourth AND gate 2222, and the S-end of the second RS flip-flop 2223 receives the execution instruction of the corresponding temperature rod group. The input ends of the second OR gate 221 are respectively connected to the output ends of the second RS flip-flops 2223 in each trigger module 222, and the output end of the second OR gate 221 outputs the selection control signal.

[00108] Refer to FIG.2 and 3. The working principle of the selection control module 22 is as follows: If the first T-bar group Tib and the second T-bar group T2b are still in the process of bar position swap, then the execution instruction 0010 for Tlb / T2b is at a high level. When at least one of the first T-bar group Tib and the second T-bar group T2b has not completed the bar position swap, at least one of the completion indication signal 0014 of the second T-bar group T2b and the completion indication signal 0015 of the first T-bar group Tib will be at a low level, meaning the output of the fourth AND gate 2222 is at a low level. Consequently, the second RS flip-flop 2223 outputs a high level, causing the selection control signal output by the second OR gate 221 to be at a high level. Understandably, the selection control signal output by the second OR gate 221 can only be at a low level after all T-bar groups have completed their bar position swaps.

[00109] In some embodiments, as shown in FIG.4, the power determination unit 1 includes a temperature measurement module 11, a latch module 12, an absolute value comparison module 13, a fifth NOT gate 14, and a pre-delay module 15.

[00110] The temperature measurement module 11 is used to collect the primary loop average temperature measured value.

[00111] The latch end of the latch module 12 receives the absolute value comparison result, and the input end of the latch module 12 is connected to the temperature measurement module 11 to obtain the primary loop average temperature measured value. The latch module 12 is used to output a latched reference value based on the absolute value comparison result. When the absolute value comparison result is at a high level, the latched reference value output by the latch module 12 is the parameter input at its input end. When the absolute value comparison result is at a low level, the latched reference value output by the latch module 12 is the output value from the previous moment.

[00112] The first end of the absolute value comparison module 13 obtains the primary loop temperature average measured value, the second end is connected to the output end of the latch module 12 to obtain the latched reference value, and the third end obtains a first preset value. The absolute value comparison module 13 is used to determine whether the absolute deviation between the primary loop average temperature measured value and the latched reference value exceeds the first preset value and outputs the absolute value comparison result through its output end. When the absolute deviation exceeds the first preset value, the absolute value comparison result is at a high level; otherwise, it is at a low level. Optionally, the first preset value may be 0.4°C.

[00113] The input end of the fifth NOT gate 14 is connected to the output end of the absolute value comparison module 13 to obtain a comparison signal, thereby performing a NOT operation on the comparison signal.

[00114] The input end of the pre-delay module 15 is connected to the output end of the fifth NOT gate 14. The pre-delay module 15 is configured to output a determination result through its output end after delaying for a first preset time. Optionally, the first preset time is 200 seconds.

[00115] Referring to FIG. 5, a schematic flowchart of a method for rod position swap in a nuclear power plant reactor according to some embodiments of the present invention is shown. The method includes the following steps:

[00116] S10: Determining whether the primary loop power is stable; if yes, proceed to the next step;

[00117] S20: Monitoring the fluctuation state of the primary loop power in real time;

[00118] S30: Performing rod position swap processing on the two T-rod groups included in each temperature rod group sequentially based on the fluctuation state.

[00119] In some embodiments, step S30 further includes: Only after the current temperature rod group completes the rod position swap, the temperature rod group that has not completed the rod position swap is allowed to perform the rod position swap processing.

[00120] In some embodiments, the step of determining whether the primary loop power is stable in step S10 includes: Within a first preset time, determining whether the absolute deviation between the primary loop average temperature measured value and the latched reference value is less than a first preset value; if yes, the primary loop power is determined to be stable; otherwise, the primary loop power is determined to be unstable.

[00121] Optionally, the first preset time is 200 seconds; and / or, the first preset value is 0.4°C.

[00122] In some embodiments, before the step S30, the method further includes: Recording the initial rod positions corresponding to all T-rod groups before performing the rod position swap processing.

[00123] The rod position swap processing in step S30 includes:

[00124] When a pause instruction input by a user is received, controlling all T-rod groups to stop at their current positions;

[00125] When no pause instruction input by a user is received, controlling the T-rod group that need to withdrawal rod position and the T-rod group that need to setback rod position to withdrawal and setback their rod positions at the same speed, respectively, until the position of the T-rod group that need to withdrawal rod position rises to the initial rod position of the T-rod group that need to setback rod position, and the position of the T-rod group that need to setback rod position drops to the initial rod position of the T-rod group that need to withdrawal rod position .

[00126] In some embodiments, as illustrated in FIG. 6, the step S30 includes:

[00127] S301: Monitoring the primary loop average temperature measured value in real time.

[00128] S302: If the difference value between the primary loop average temperature set value and the primary loop average temperature measured value exceeds a first limit, control the T-rod group performing rod position swap that requires setback to pause the setback operation.

[00129] S303: If the difference value between the primary loop average temperature set value and the primary loop average temperature measured value is below a second limit, control the T-rod group performing rod position swap that requires withdrawal to pause the withdrawal operation.

[00130] Optionally, the first limit is 0.3°C, and the second limit is -0.3°C.

[00131] The embodiments in this specification are described in a progressive manner, with each embodiment focusing on differences from other embodiments. Similar or identical parts between embodiments can be cross-referenced. For the apparatus disclosed in the embodiments, since it corresponds to the methods disclosed in the embodiments, the description is relatively brief, and relevant details can be found in the method section.

[00132] Professionals may further recognize that the units and algorithm steps described in the examples disclosed in the embodiments can be implemented using electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of functionality in the foregoing description. Whether these functions are executed by hardware or software depends on the specific application and design constraints of the technical solution. Professionals may use different methods for each specific application to implement the described functionality, but such implementations should not be considered beyond the scope of the present invention.

[00133] The steps of the methods or algorithms described in the embodiments disclosed herein can be implemented directly via hardware, software modules executed by a processor, or a combination of both. Software modules may reside in random-access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium known in the technical field.

[00134] It should be understood that the above embodiments only express preferred implementations of the present invention, and the descriptions are specific and detailed, but should not be construed as limiting the scope of the patent. It should be noted that, for those skilled in the art, without departing from the inventive concept, the technical features described above may be freely combined, and further modifications and improvements may be made, all of which fall within the protection scope of the present invention. Therefore, any equivalent modifications or variations made within the scope of the claims of the present invention shall be covered by the claims of the present invention.

Claims

1. A system for rod position swap in a nuclear power plant reactor, the system comprising:a power determination unit (1) configured to determine whether the primary loop power is stable and generate a determination result indicating whether the primary loop power is stable;a power fluctuation prevention unit (2) configured to monitor the fluctuation state of the primary loop power in real time; anda rod position swap execution unit (3) configured to perform rod position swap processing sequentially on the first and second T-rod groups included in each temperature rod group based on the fluctuation state after determining that the primary loop power is stable.

2. The system for rod position swap in a nuclear power plant reactor according to claim 1, further comprising:a sequence control unit (4) configured to send an execution instruction to the rod position swap execution unit (3) according to a preset rule to control each temperature rod group to perform rod position swap processing, so that only after the current temperature rod group completes the rod position swap, the temperature rod groups that have not completed the swap will be controlled to perform the rod position swap processing.

3. The system for rod position swap in a nuclear power plant reactor according to claim 1 or 2, further comprising: a memory unit (5) configured to record the initial rod positions corresponding to all T-rod groups before performing the rod position swap processing;wherein the rod position swap execution unit (3) comprises a control rod actuation mechanism (31) configured to control the withdrawal or setback of T-rod group based on a withdrawal / setback instruction, and multiple rod-group pair execution units corresponding one-to-one with each temperature rod group;each of the rod-group pair execution units comprises:a start-stop control module (321) configured to obtain a pause instruction, a termination instruction, and an execution instruction for the corresponding temperature rod group to generatea start-stop instruction;a first rod group execution module (322) configured to obtain the start-stop instruction, the real-time rod position of the first T-rod group, and the initial rod position of the second T-rod group to generate a withdrawal / setback instruction for the first T-rod group of the corresponding temperature rod group; anda second rod group execution module (323) configured to obtain the start-stop instruction, the real-time rod position of the second T-rod group, and the initial rod position of the first T-rod group to generate a withdrawal / setback instruction for the second T-rod group of the corresponding temperature rod group.

4. The system for rod position swap in a nuclear power plant reactor according to claim 3, wherein the first and second rod group execution modules each comprising:a comparison module (3221), wherein its second input end obtains the real-time rod position of the corresponding T-rod group, its first input end obtains the initial rod position of the other paired T-rod group, its first output end outputs an setback signal for the corresponding T-rod group, its second output end outputs a completion indication signal indicating whether the corresponding T-rod group has completed the withdrawal / setback action, and its third output end outputs a withdrawal signal for the corresponding T-rod group;a first AND gate (3222), wherein each of its input ends obtains an unlocked setback signal, the start-stop instruction, and the setback signal, and its output end outputs a setback instruction for the corresponding T-rod group; anda second AND gate (3223), wherein each of its input ends obtains an unlocked withdrawal signal, the start-stop instruction, and the withdrawal signal, and its output end outputs a withdrawal instruction for the corresponding T-rod group.

5. The system for rod position swap in a nuclear power plant reactor according to claim 4, wherein, the start-stop control module (321) comprises:a first RS flip-flop (3211), wherein its R-end receives the execution instruction, and itsS-end receives the termination instruction;a first OR gate (3212), wherein one input end receives the pause instruction, and the other input end is connected to the output end of the first RS flip-flop (3211); anda first NOT gate (3213), wherein its input end is connected to the output end of the first OR gate (3212), and its output end outputs the start-stop instruction.

6. The system for rod position swap in a nuclear power plant reactor according to claim 1 or2, wherein, the power fluctuation prevention unit (2) comprises:a subtractor module (21), wherein its first end receives a primary loop average temperature set value, and its second end receives a primary loop average temperature measured value, configured to calculate the difference value between the primary loop average temperature set value and the primary loop average temperature measured value;a selection control module (22), configured to receive the completion indication signals of each T-rod group and the execution instructions of each temperature rod group to generate a selection control signal;a selection module (23), wherein its first input end receives the difference value, and its selection end receives the selection control signal, so as to determine whether to output the difference value based on the selection control signal;a first limit comparison module (24), configured to output an unlock setback signal when the difference value is greater than a first limit, which can control the T-rod group currently performing rod position swap that need to rod setback to pause the setback;and a second limit comparison module (25), configured to output an unlock withdrawal signal when the difference value is less than a second limit, which can control the T-rod group currently performing rod position swap that need to rod withdrawal to pause the withdrawal.

7. The system for rod position swap in a nuclear power plant reactor according to claim 6, wherein, the selection control module (22) comprises a second OR gate (221) and multiple trigger modules (222) corresponding one-to-one with each temperature rod group;wherein each trigger module (222) comprises:a third OR gate (2221), wherein its first and second input ends respectively receive the completion indication signals of two T-rod groups in the corresponding temperature rod group;a fourth AND gate (2222), wherein its first input end is connected to the output end of the third OR gate (2221), and its second input end receives the execution instruction of the corresponding temperature rod group;a second RS flip-flop (2223), wherein its R-end is connected to the output end of the fourth AND gate (2222), and its S-end receives the execution instruction of the corresponding temperature rod group;the second OR gate (221) has its input ends respectively connected to the output ends of the second RS flip-flops (2223) included in each trigger module (222), and the output end of the second OR gate (221) outputs the selection control signal.

8. The system for rod position swap in a nuclear power plant reactor according to claim 1 or 2, wherein the power determination unit (1) comprises:a temperature measurement module (11) for collecting a primary loop average temperature measured value;a latch module (12), wherein a latch end is configured to receive an absolute value comparison result, an input end is connected to the temperature measurement module (11) to obtain the primary loop average temperature measured value, and the latch module is configured to output a latched reference value based on the absolute value comparison result;an absolute value comparison module (13), wherein a first end is configured to obtain the primary loop average temperature measured value, a second end is connected to an output end of the latch module (12) to obtain the latched reference value, a third end is configured to obtain a first preset value, and the absolute value comparison module is configured to determine whether an absolute deviation between the primary loop average temperature measured value and the latched reference value is greater than the first preset value and output the absolute value comparison result via an output end;a fifth NOT gate (14), wherein an input end is connected to the output end of the absolute value comparison module (13) to obtain the comparison signal and perform a NOT operation on the comparison signal; anda pre-delay module (15), wherein an input end is connected to an output end of the fifth NOT gate (14), and the pre-delay module is configured to output the determination result via an output end after delaying for a first preset time.

9. A method for rod position swap in a nuclear power plant reactor, wherein the method comprising:S10: determining whether the primary loop power is stable, and if so, proceeding to the next step;S20: monitoring the fluctuation state of the primary loop power in real time;S30: performing rod position swap processing sequentially on two T-rod groups included in each temperature rod group according to the fluctuation state.

10. The method for rod position swap in a nuclear power plant reactor according to claim 9, wherein, in S30, it further comprises: only after the current temperature rod group completes the rod position swap, allowing the temperature rod groups that have not completed the rod position swap to perform the rod position swap processing.

11. The method for rod position swap in a nuclear power plant reactor according to claim 9, wherein, in S10, the step of determining whether the primary loop power is stable comprises:within a first preset time, determining whether the absolute deviation between the primary loop average temperature measured value and a latched reference value is less than a first preset value, and if so, determining that the primary loop power is stable; otherwise, determining that the primary loop power is unstable.

12. The method for rod position swap in a nuclear power plant reactor according to claim11, wherein the first preset time is 200 seconds; and / or, the first preset value is 0.4°C.

13. The method for rod position swap in a nuclear power plant reactor according to claim 9, wherein, before S30, it further comprises: recording the initial rod positions corresponding to all T-rod groups before performing the rod position swap processing;in S30, the rod position swap processing comprises:when a pause instruction input by a user is received, controlling all T-rod groups to stop at their current positions;when no pause instruction input by the user is received, controlling the T-rod group that need to withdrawal its rod position and the T-rod group that need to setback its rod position to withdrawal and setback their rod positions at the same speed, respectively, until the position of the T-rod group that need to withdrawal its rod positions rises to the initial rod position of the T-rod group that need to setback its rod position, and the position of the T-rod group that need to setback its rod position drops to the initial rod position of the T-rod group that need to withdrawal its rod position.

14. The method for rod position swap in a nuclear power plant reactor according to any one of claims 9 to 13, wherein that in S30 comprises:S301: monitoring the primary loop average temperature measured value in real time;S302: if the difference value between the primary loop average temperature set value and the primary loop average temperature measured value is greater than a first limit, controlling the T-rod group that is performing the rod position swap processing and need to setback its rod position to pause setback its rod position;S303: if the difference value between the primary loop average temperature set value and the primary loop average temperature measured value is less than a second limit, controlling the T-rod group that is performing the rod position swap processing and need to withdrawal its rod position to pause withdrawal its rod position.

15. The method for rod position swap in a nuclear power plant reactor according to claim14, wherein that the first limit is 0.3°C, and the second limit is -0.3°C.INTERNATIONAL SEARCH REPORT International application No. PCT / CN2023 / 138585 A. CLASSIFICATION OF SUBJECT MATTER G21C7 / 12(2006.01)i; G21C17 / 104(2006.01)i; G21C17 / 112(2006.01)i According to International Patent Classification (IPC) or to both national classification and IPC B. FIELDS SEARCHED Minimum documentation searched (classification system followed by classification symbols) G21C (IPC) Documentation searched other than minimum documentation to the extent that such documents are included in the fields searched Electronic data base consulted during the international search (name of data base and, where practicable, search terms used) CNTXT, ENTXTC, DWPI, CNKI: EffO, B#, TW, BS, 1®^], nuclear power, control rod, exchang+, power, stabl+, fluctuat+, position C. DOCUMENTS CONSIDERED TO BE RELEVANT Category* Citation of document, with indication, where appropriate, of the relevant passages Relevant to claim No. PX CN 117012412 A (CHINA NUCLEAR POWER ENGINEERING CO., LTD. et al.) 07 November 2023 (2023-11-07) claims 1-15, description, paragraphs 0071-0130, and figures 1-6 1-15 X v A. CN 106531236 A (CHINA NUCLEAR POWER ENGINEERING CO., LTD. et al.) 22 March 2017 (2017-03-22) description, paragraphs 0040-0080, and figures 1-5 (YAN, Su et al.). (Non-official translation: Brief Analysis of Control Rod Control Strategy of Third Generation Nuclear Power Plant)" (Science &Technology Vision), 25 March 2015 (2015-03-25), sections 1-5 1-15 1-15 A CN 114783632 A (CHINA GENERAL NUCLEAR POWER CO., LTD. et al.) 22 July 2022 (2022-07-22) entire document 1-15 A CN 112750544 A (CHINA GENERAL NUCLEAR POWER CO., LTD. et al.) 04 May 2021 (2021-05-04) entire document 1—15 | | Further documents are listed in the continuation of Box C. | J | See patent family annex. * Special categories of cited documents: “T” later document published after the international filing date or priority “A” document defining the general state of the art which is not considered date and not in conflict with the application but cited to understand the to be of particular relevance principle or theory underlying the invention “D” document cited by the applicant in die international application “X” document of particular relevance; the claimed invention cannot be “E" earlier application orpatent but published on or after the international considered novel or cannot be considered to involve an inventive step filing date when the document is taken alone •SL” document which may throw doubts on priority claim(s) or which is “Y” document of particular relevance; the claimed invention cannot be cited to establish the publication date of another citation or other considered to involve an inventive step when the document is special reason (as specified) combined with one or more other such documents, such combination “O” document referring to an oral disclosure, use, exhibition or other being obvious to a person skilled in the art means document member of the same patent family “P” document published prior to the international filing date but later than the priority date claimed Date of the actual completion of the international search 21 March 2024 Date of mailing of the international search report 01 April 2024 Name and mailing address of the ISA / CN China National Intellectual Property Administration (ISA / CN) China No. 6, Xitucheng Road, Jimenqiao, Haidian District, Beijing 100088 Authorized officer Telephone No.

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