A control method and device for canceling active exhaust of a reactor coolant main pump and a computer readable storage medium

Abstract

The application provides a control method and device for canceling active exhaust of a reactor coolant main pump and a computer readable storage medium, and comprises: performing vacuumizing operation on a primary loop system of a nuclear power plant; filling water to the primary loop system after the vacuumizing operation is completed and performing static exhaust; monitoring the final gas content of the primary loop system, and if the final gas content meets a preset condition, controlling the low-pressure safety injection to operate in an SI mode; and after the low-pressure safety injection operates in the SI mode, directly starting the main pump to replace the execution of the active exhaust operation. The operation method, device and computer readable storage medium for canceling the active exhaust of the reactor coolant main pump can improve the technical problem of additional time limit.

Description

Technical Field

[0001] This invention relates to the field of nuclear power equipment operation and maintenance technology, and in particular to a control method, device and computer-readable storage medium for canceling active venting of the reactor coolant main pump. Background Technology

[0002] The reactor coolant main pump, as the core power equipment of the primary loop system in a pressurized water reactor nuclear power plant, is known as the "heart" of the primary loop. Its main function is to drive the circulation of reactor coolant, continuously removing heat generated by the reactor core and ensuring the safe and stable operation of the nuclear power unit. In traditional nuclear power plant operation and maintenance procedures, an active venting operation must be performed before starting the main pump to remove residual gases from the pump chamber and high-pressure cooler to prevent cavitation, excessive vibration, shaft seal failure, and other malfunctions during main pump operation, ensuring the safety of main pump operation. However, this operation adds approximately 13 hours to the unit's operational time, not only reducing unit availability and power generation economic efficiency but also increasing the high-risk work time for maintenance personnel on-site, raising the risk of misoperation and equipment damage. Summary of the Invention

[0003] This invention provides a control method, apparatus, and computer-readable storage medium for canceling active venting of the reactor coolant main pump, in order to improve the technical problem of additional time constraints.

[0004] This invention provides a control method for canceling active venting of the reactor coolant main pump, comprising: Vacuuming operations were carried out on the primary loop system of the nuclear power plant. Water is added to the primary loop system after vacuuming, and static venting is performed. Monitor the final gas content of the primary loop system. If the final gas content meets the preset conditions, control the low-pressure safety injection to operate in SI mode. After the low-pressure safety injection is running in SI mode, the main pump is started directly to replace the active venting operation.

[0005] In one embodiment of the present invention, the vacuuming operation of the primary loop system of a nuclear power plant specifically includes: A vacuum pump is used to pump the pressure of the primary loop system to a first preset pressure threshold and maintain the pressure for a preset time in order to verify the system's sealing performance. After completing the system sealing test, continue to evacuate until the absolute pressure of the primary loop system reaches the second preset pressure threshold. Once the absolute pressure of the primary loop system reaches the second preset pressure threshold, the vacuum pump will be switched to automatic control mode.

[0006] In one embodiment of the present invention, the first preset pressure threshold is 0.6 bar.a to 0.9 bar.a.

[0007] In one embodiment of the present invention, the preset time is 10 min to 20 min.

[0008] In one embodiment of the present invention, the second preset pressure threshold is 0.1 bar.a to 0.3 bar.a.

[0009] In one embodiment of the present invention, the automatic control mode includes: setting the inlet pressure start / stop threshold of the vacuum pump, automatically starting the vacuum pump when the absolute pressure of the primary loop system is higher than 0.24 bar.a, and automatically stopping the vacuum pump when the absolute pressure of the primary loop system is lower than 0.155 bar.a.

[0010] In one embodiment of the present invention, filling the primary loop system, which has undergone vacuuming, with water and performing static venting specifically includes: Fill the primary loop system with water after vacuuming. Stop vacuuming and filling with water when the pressure regulator level reaches 95%. Then perform static venting on the primary loop system.

[0011] In one embodiment of the present invention, the final gas content of the primary loop system is monitored. If the final gas content meets the preset conditions, the low-pressure safety injection is controlled to operate in SI mode. Specifically, if the final gas content is ≤27Nm³, the low-pressure safety injection is controlled to operate in SI mode.

[0012] In one embodiment of the present invention, after the low-pressure injection is operated in SI mode, the main pump is directly started to replace the active venting operation, followed by: Obtain one or more parameters of the reactor coolant main pump, including pump casing material, impeller structure, sealing type, and cavitation resistance, and combine them with the gas content detection data of the primary loop system to conduct an impact analysis on one or more of the pump casing, impeller, and seal of the reactor coolant main pump, and form a risk assessment signal. The real-time operating parameters of the reactor coolant main pump are obtained, and the real-time operating parameters are compared with the design standard thresholds. If the real-time operating parameters meet the design standard thresholds, a target dataset containing the real-time operating parameters is generated. The target dataset and risk assessment signal are transmitted to the external device management terminal, and the approval instruction fed back by the external device management terminal based on the target dataset is received. The approval instruction indicates that the main pump system meets the preset safe operation conditions. In response to the received approval instruction, the operation and maintenance procedures and overhaul operation manuals for the reactor coolant main pump were revised and incorporated into the standardized operation and maintenance process.

[0013] In one embodiment of the present invention, in response to receiving an approval instruction, the operation and maintenance procedures and overhaul instructions for the reactor coolant main pump are revised and incorporated into the standardized operation and maintenance process, which then includes: The target dataset was stored in a long-term operational database to establish an operational reliability verification model for the reactor coolant main pump.

[0014] The present invention also provides a control device for canceling active venting of the reactor coolant main pump, comprising: The vacuum module is used to perform vacuuming operations on the primary loop system of a nuclear power plant. The static venting module is used to fill the primary loop system with water after vacuuming and to perform static venting. The monitoring and control module is used to monitor the final gas content of the primary loop system. If the final gas content meets the preset conditions, it controls the low-pressure safety injection to operate in SI mode. The startup module, after operating in SI mode under low-pressure safety injection, directly starts the main pump to replace the active venting operation.

[0015] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the above-described control method for canceling active venting of the reactor coolant main pump.

[0016] The beneficial effects of this invention are: The present invention discloses a control method, apparatus, and computer-readable storage medium for eliminating active venting of the reactor coolant main pump. First, a vacuum operation is performed on the primary loop system of the nuclear power plant. Then, water is introduced into the evacuated primary loop system, and static venting is carried out. Next, the final gas content of the primary loop system is monitored. If the final gas content meets preset conditions, the low-pressure safe injection system is controlled to operate in SI mode. After the low-pressure safe injection system operates in SI mode, the main pump is directly started to replace the active venting operation. This solves the problems of long operation time, high cost, and high operational risk associated with traditional active venting operations. While ensuring the safe operation of the main pump, active venting operations are eliminated, the overhaul period is shortened, and the intrinsic safety and maintenance efficiency of the unit are improved. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0018] In the attached diagram: Figure 1 This is a schematic diagram illustrating the principle and structure of existing active exhaust operation technology. Figure 2 A schematic diagram illustrating the principle structure of a control method for canceling active venting of the reactor coolant main pump according to an embodiment of the present invention; Figure 3A schematic diagram of the flow structure of a control method for canceling active venting of the reactor coolant main pump according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the principle structure of a control device for canceling active venting of the reactor coolant main pump, provided in an embodiment of the present invention. Detailed Implementation

[0019] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0020] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0021] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the invention. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the invention.

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, before describing the specific embodiments in detail, it should be noted that the active exhaust operation in the background art of this application would result in an additional 13 hours of unit operation time (see...). Figure 1The fundamental reason is that this operation is not a single venting action, but a series of complex and time-consuming processes. Specifically, the active venting operation first requires the C-column (safety systems are usually configured redundantly and divided into multiple independent sequences by letter) low-pressure safety injection (i.e., low-pressure safety injection is one of the subsystems of the emergency core cooling system, used to inject cooling water into the reactor core in the event of a loss-of-coolant accident or main steam pipe rupture accident to prevent overheating and damage to the fuel cladding) to run in SI mode (SI mode is the safety injection mode, which refers to the operation state in which the safety injection system switches from standby to actively inject water into the core for emergency cooling and shutdown after detecting an accident signal (such as loss of coolant)). After this, the three main pumps are jogged at the 24.5 bar platform, then the C-column low-pressure safety injection running in SI mode is shut down, and then the main pumps are jogged again to recalculate. The process involves calculating the gas content of the primary loop and switching the primary loop pressure control from high-pressure venting to low-pressure venting. Next, the primary loop pressure needs to be reduced to a 1.5 bar level for static venting of the pressure regulator, pressure vessel, main pump casing, and main pump high-pressure cooler. Afterward, the primary loop pressure is raised back to a 24.5 bar level. Finally, after the primary loop gas content is recalculated and deemed acceptable, the low-pressure injection system in column C operates in SI mode before the main pump can be started. This series of cumbersome procedures, including multiple pressure increases and decreases, equipment start-ups and shutdowns, gas content calculations, and static venting, significantly extends the construction period, reduces unit availability and power generation economics, and increases the time maintenance personnel spend working at high risk on-site, raising the risk of misoperation and equipment damage. To address the technical challenges of this extended construction period, this invention adopts the following technical solution.

[0023] Please see Figures 2 to 3 This invention provides a control method for canceling active venting of the reactor coolant main pump, comprising: Step S1: Perform vacuuming on the primary loop system of the nuclear power plant; In this step, the vacuuming operation of the primary loop system of the nuclear power plant can be performed using conventional methods in the art. For example, a temporary vacuum pump can be connected to the high-point exhaust valve of the main pump casing for vacuuming, or the existing charging pump and drain circuit of the primary loop system can be used for vacuuming. However, in one embodiment of the present invention, the vacuuming operation of the primary loop system of the nuclear power plant specifically includes: Step S11: Use a vacuum pump to pump the pressure of the primary loop system to the first preset pressure threshold and maintain the pressure for a preset time to perform system sealing verification. This step, before formally evacuating, involves evacuating the primary loop system to the first preset pressure threshold and maintaining that pressure for a preset time. This allows for a preliminary test of the primary loop system's tightness, verifying the vacuum system's integrity and preventing air backflow due to leaks under subsequent low-pressure conditions. It also ensures the reliability of the entire venting process, avoiding rework caused by system leaks and guaranteeing operational safety from the outset, thus ensuring both system tightness and operational safety.

[0024] Furthermore, the first preset pressure threshold and preset time in this step can be flexibly set according to actual usage needs. In one embodiment of the present invention, the first preset pressure can be any value between 0.6 bar.a and 0.9 bar.a, such as 0.6 bar.a, 0.7 bar.a, 0.8 bar.a, 0.9 bar.a, etc. However, the first preset pressure threshold is preferably 0.8 bar.a, which is slightly lower than the standard atmospheric pressure (about 1.01 bar.a), and is in an ideal low-pressure detection window. Under this pressure, the internal and external pressure difference of the primary loop system is moderate, which can not only use a highly sensitive pressure sensor to quickly and accurately capture small pressure rises, thereby efficiently completing the sealing verification, but also avoid the water in the loop from flashing or vaporizing due to excessively low pressure (such as close to the saturated vapor pressure of water), thus interfering with the accuracy of the leak detection results. In addition, the pressure level of 0.8 bar.a can be easily achieved quickly by a conventional vacuum pump without consuming too much suction time, ensuring the efficiency and accuracy of the sealing verification process, and laying a solid foundation for subsequent deep vacuuming operations.

[0025] In one embodiment of the present invention, the preset time can be any value between 10 min and 20 min, such as 10 min, 12 min, 15 min, 17 min, 20 min, etc. However, the preset time is preferably 15 min. Setting the pressure holding preset time to 15 min can achieve the best balance between ensuring leak detection reliability and improving work efficiency. In the large-volume system of the nuclear power plant primary loop, the 15-minute time window is sufficient for the gas adiabatic compression heat or expansion cold caused by pressure fluctuations in the system to be completely dissipated, so that the pressure reading returns to the thermodynamically stable state, thereby effectively eliminating the interference of temperature drift on the judgment of sealing. At the same time, this duration is sufficient to capture significant leaks caused by flange loosening or seal failure under the micro-negative pressure condition of 0.8 bar.a, avoiding misjudgment due to too short observation time and preventing the waste of time due to too long time, significantly improving the flow efficiency of the vacuum preparation stage.

[0026] Step S12: After completing the system sealing test, continue to evacuate until the absolute pressure of the primary loop system reaches the second preset pressure threshold. In this step, the vacuum level is further reduced to the second preset threshold (i.e., a lower absolute pressure), so that the absolute pressure in the primary loop system is closer to the saturated vapor pressure of water. This promotes the full release and discharge of trace gases dissolved in the water and gases trapped in the dead zone. This deep vacuum method greatly reduces the initial gas content before the main pump starts, effectively eliminates the risk of gas binding, significantly improves the hydraulic stability after the main pump starts, and enhances the thoroughness of venting and the stability of the main pump operation.

[0027] Furthermore, the second preset pressure threshold in this step can be flexibly set according to actual usage needs. In one embodiment of the present invention, the second preset pressure threshold can be any value between 0.1 bar.a and 0.3 bar.a, such as 0.1 bar.a, 0.2 bar.a, 0.25 bar.a, 0.3 bar.a, etc. However, the second preset pressure threshold is preferably 0.2 bar.a. This pressure value is significantly lower than the standard atmospheric pressure (about 1.01 bar.a), which generates a large pressure gradient. This strongly drives non-condensable gases such as nitrogen to escape from the liquid phase and be removed, effectively promoting the full desorption and discharge of trace gases dissolved in water and stagnant dead zone gases. It also avoids flash evaporation or vaporization of water in the circuit due to excessively low pressure (such as close to the saturated vapor pressure of water), and prevents water vapor from occupying the vacuum pump's suction energy. The setting of 0.2 bar.a achieves the best balance between ensuring effective degassing efficiency and preventing excessive vaporization of the medium, ensuring the safety, controllability, and efficiency of the exhaust process.

[0028] Step S13: After the absolute pressure of the primary loop system reaches the second preset threshold, switch the vacuum pump to automatic control mode.

[0029] This step automatically switches to automatic control mode after the target vacuum level is reached. The automatic maintenance function of the vacuum pump replaces the traditional manual operation and intermittent operation. This not only reduces the on-site operation burden of maintenance personnel, but also ensures the continuous stability of the vacuum environment, avoids human operation errors, further shortens the preparation period, improves the overall operation and maintenance efficiency, and reduces labor costs.

[0030] In one embodiment of the present invention, the automatic control mode may include: setting a vacuum pump inlet pressure start / stop threshold; the vacuum pump automatically starts when the absolute pressure of the primary loop system is higher than 0.24 bar·a, and automatically stops when the absolute pressure of the primary loop system is lower than 0.155 bar·a. This sets the automatic control mode to start above 0.24 bar·a and stop below 0.155 bar·a, thus establishing a reasonable pressure control dead zone (Hysteresis loop) with a width of approximately 0.085 bar. The start-up threshold of 0.24 bar.a serves as a safety upper limit, ensuring that the vacuum pump intervenes immediately before the primary loop system pressure rises to a critical point affecting the exhaust effect, preventing the system vacuum from deteriorating. The shutdown threshold of 0.155 bar.a is slightly lower than the aforementioned exhaust target pressure (0.2 bar.a), ensuring that the system is in a deep vacuum state at the moment of shutdown, providing sufficient safety margin for subsequent operations, and effectively avoiding frequent start-stop or oscillation phenomena caused by small pressure fluctuations around a single set point. While ensuring the continuous stability of the primary loop vacuum environment, it significantly reduces the impact of frequent starts and mechanical wear, extends the service life of the equipment, and achieves dual optimization of operation and maintenance safety and economy.

[0031] Step S2: Fill the primary loop system with water after vacuuming and perform static venting; This step may specifically include: filling the primary loop system with water after vacuuming; stopping vacuuming and water filling when the pressurizer level reaches 95%; and then performing static venting on the primary loop system. When the pressurizer level reaches 95%, it indicates that the primary loop system is basically filled with liquid and most of the free space has been compressed to the top of the pressurizer. At this point, stopping dynamic water filling and switching to static venting provides sufficient residence and precipitation time for trace amounts of non-condensable gases remaining at high points and dead corners of the system. This not only effectively avoids the risk of liquid backflow caused by overfilling, but also ensures the thoroughness of the venting process and the accuracy of the system water level through precise control of the pressurizer level, thereby significantly improving the safety and reliability of the nuclear power plant's primary loop system before startup.

[0032] Step S3: Monitor the final gas content of the primary loop system. If the final gas content meets the preset conditions, control the low-pressure safety injection to operate in SI mode. In this step, the final gas content of the primary loop system is monitored. If the final gas content is ≤27 Nm³, the low-pressure injection pump is controlled to operate in SI mode. This embodiment is based on a comprehensive consideration of the primary loop system volume, the hydraulic performance boundary of the low-pressure injection pump, and the safety margin. The final gas content of ≤27 Nm³ is set as the condition for triggering the low-pressure injection pump to operate in SI mode. The quantitative index of 27 Nm³ essentially corresponds to the maximum residual gas space volume that the primary loop can have in a full water state. When the monitored gas content is lower than this value, the free gas in the system has been fully discharged, and the fluid continuity is guaranteed. At this time, starting the low-pressure injection pump can fundamentally avoid the risks of flow pulsation, head reduction, and mechanical vibration caused by gas accumulation. It ensures that the coolant can be stably injected into the reactor core at the designed flow rate in SI mode, thereby establishing a safety barrier to prevent the reactor core from being exposed at the physical level, and at the same time protecting the pump equipment from cavitation damage.

[0033] Step S4: After the low-pressure safety injection is running in SI mode, start the main pump directly to replace the active venting operation.

[0034] This step involves directly starting the main pump after low-pressure safety injection in SI mode, replacing the need for active venting. This solves the problems of long operation time, high cost, and high operational risk associated with traditional active venting. Under the premise of ensuring the safe operation of the main pump, it eliminates the need for active venting, shortens the overhaul period, and improves the inherent safety and operation and maintenance efficiency of the unit.

[0035] Since the main pump is directly started after low-pressure safety injection in SI mode to replace the active venting operation, changing the traditional active venting method, it is necessary to strictly monitor and confirm the operating status of the main pump after startup to ensure that the system can still operate safely and stably without active venting. Based on this, in one embodiment of the present invention, after low-pressure safety injection in SI mode, the main pump is directly started to replace the active venting operation, followed by: Step S5: Obtain one or more parameters of the reactor coolant main pump, including pump casing material, impeller structure, sealing type and anti-cavitation performance, and combine them with the gas content detection data of the primary loop system to conduct an impact analysis on one or more of the pump casing, impeller and seal of the reactor coolant main pump, and form a risk assessment signal. In this step, by acquiring one or more parameters of the reactor coolant main pump, such as the pump casing material, impeller structure, sealing type, and cavitation resistance, and combining them with the gas content detection data of the primary loop system, an impact analysis of residual gas on the key components of the reactor coolant main pump is conducted to form a risk assessment signal. By specifically considering the impact analysis of residual gas on the key components of the reactor coolant main pump, the actual impact boundary of residual gas on the mechanical performance of the main pump can be accurately defined. This provides a scientific basis based on the characteristics of the equipment itself for the start-up of the main pump after the cancellation of active venting operation, effectively avoiding equipment safety hazards that may be caused by general experience judgments, and ensuring the operational reliability of the main pump.

[0036] Step S6: Obtain the real-time operating parameters of the reactor coolant main pump, compare the real-time operating parameters with the design standard threshold, and generate a target dataset containing the real-time operating parameters if all the real-time operating parameters meet the design standard threshold. In this step, the cold commissioning phase of the unit can be selected as the verification window. The main pump can be started up sequentially at three typical pressure platforms: 24.5 bar.g, 109 bar.g, and 154 bar.g. Real-time monitoring is performed throughout the process to obtain key operating parameters such as main pump outlet pressure, flow rate, radial vibration value, casing temperature, and shaft seal differential pressure. Then, the real-time operating parameters are compared with the design standard thresholds. For example, the real-time operating parameters can be compared with the design standard thresholds (which can be provided by the manufacturer) to confirm that the main pump operating parameters meet the design standards and that there are no faults such as cavitation, abnormal vibration, or seal leakage. When all real-time operating parameters meet the design standard thresholds, a target dataset containing the real-time operating parameters is generated. Step S7: Transmit the target dataset and risk assessment signal to the external device management terminal, and receive the approval instruction fed back by the external device management terminal based on the target dataset. The approval instruction indicates that the main pump system meets the preset safe operation conditions. In this step, the target dataset and evaluation signal are transmitted to an external device management terminal (which can be the manufacturer's management terminal). The manufacturer's management terminal receives an approval instruction based on the target dataset. The approval instruction indicates that the main pump system meets the preset safe operating conditions.

[0037] Step S8: In response to receiving the approval instruction, revise the operation and maintenance procedures and overhaul operation manual for the reactor coolant main pump and incorporate them into the standardized operation and maintenance process.

[0038] In this step, after receiving the approval instruction from the manufacturer's management terminal, the operation and maintenance procedures and overhaul operation manual for the reactor coolant main pump are revised, and the above-mentioned vacuuming process, static exhaust requirements, and parameter monitoring standards are incorporated into the standardized operation and maintenance process.

[0039] In one embodiment of the present invention, step S8 may include the following: Step S9: Store the target dataset into a long-term operational database to establish an operational reliability verification model for the reactor coolant main pump.

[0040] In this step, following the standardized process established above, during the unit overhaul start-up and fuel loading start-up phases, once the gas content in the primary loop system reaches the standard (i.e., gas content ≤ 27 Nm³), the main pump is started directly, and active venting operations are cancelled throughout the process. The long-term operating parameters of the main pump are continuously tracked and stored in the long-term operating database to establish a reliability verification model for the reactor coolant main pump, thereby verifying the long-term reliability of the reactor coolant main pump.

[0041] The following is an embodiment of the control method of the present invention: First, the vacuum pump was started to evacuate the primary loop system. When the pressure dropped to 0.8 bar.a, it was held for 15 minutes to check for leaks. After confirming that there were no leaks, the vacuum was continued to 0.2 bar.a, and the vacuum pump was switched to automatic control mode. Then, water was slowly added to the primary loop system until the pressure regulator level reached 95%, at which point static venting was performed. Testing showed that the final gas content of the system was 11.826 Nm³, meeting the control target of ≤27 Nm³. Based on the forged stainless steel pump casing, 4-blade mixed-flow impeller, and three-stage dynamic pressure seal design of the KSB RSR750 main pump, its cavitation resistance and structural strength are no less than those of the Thermion main pump. Safety analysis confirmed that trace amounts of residual gas (i.e., the final gas content) will not damage the main pump. In subsequent multi-condition verification, the main pump was started sequentially at three pressure platforms: 24.5 bar.g, 109 bar.g, and 154 bar.g. Key parameters such as casing temperature and shaft seal differential pressure all met design requirements, and no cavitation or leakage faults were observed. The verification results received approval from the manufacturer's management terminal, and the operation and maintenance procedures were revised accordingly, incorporating this optimized process into the standard workflow. Ultimately, active venting was eliminated throughout the process, and the main pump operated continuously and stably with no abnormalities in any parameters.

[0042] In summary, the control method for canceling active venting of the reactor coolant main pump of the present invention belongs to the field of nuclear power equipment operation and maintenance technology. It is applicable to the KSB main pump of reactor coolant in nuclear power plants and can solve the problems of long operation period, high cost and high operation risk of traditional active venting operation. Under the premise of ensuring the safe operation of the main pump, it can realize the cancellation of active venting operation, shorten the overhaul period, and improve the inherent safety and operation and maintenance efficiency of the unit.

[0043] Please see Figure 4The present invention also provides a control device for canceling active venting of the reactor coolant main pump, comprising: a vacuum module 110 for performing vacuuming operations on the primary loop system of a nuclear power plant; a static venting module 111 for filling the primary loop system with water after vacuuming and performing static venting; a monitoring and control module 112 for monitoring the final gas content of the primary loop system, and controlling the low-pressure safe injection to operate in SI mode if the final gas content meets preset conditions; and a start-up module 113 for directly starting the main pump after the low-pressure safe injection is operating in SI mode, in order to replace the active venting operation.

[0044] It should be noted that the control method and device for canceling active venting of the reactor coolant main pump provided in the above embodiments belong to the same concept. The specific operation methods of each module have been described in detail in the method embodiments and will not be repeated here. In practical applications, the control device for canceling active venting of the reactor coolant main pump provided in the above embodiments can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. This is not a limitation.

[0045] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the above-described control method for canceling active venting of the reactor coolant main pump.

[0046] It should be noted that the computer-readable medium shown in the embodiments of this application can be a computer-readable signal medium or a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, carrying a computer-readable computer program. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media can also be any computer-readable medium other than computer-readable storage media, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The computer program contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.

[0047] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A control method for canceling active venting of the reactor coolant main pump, characterized in that, include: Vacuuming operations were carried out on the primary loop system of the nuclear power plant. Water is added to the primary loop system after the vacuum has been completed, and static venting is carried out; Monitor the final gas content of the primary loop system. If the final gas content is ≤27Nm³, control the low-pressure safety injection to operate in SI mode. After the low-pressure injection is running in the SI mode, the main pump is started directly to replace the active venting operation; Obtain one or more parameters of the reactor coolant main pump, including pump casing material, impeller structure, sealing type, and cavitation resistance, and combine them with the gas content detection data of the primary loop system to conduct an impact analysis on one or more of the pump casing, impeller, and seal of the reactor coolant main pump, and form a risk assessment signal. The real-time operating parameters of the reactor coolant main pump are obtained, and the real-time operating parameters are compared with the design standard threshold. In response to the real-time operating parameters meeting the design standard threshold, a target dataset containing the real-time operating parameters is generated. The target dataset and risk assessment signal are transmitted to the external device management terminal, and an approval instruction is received from the external device management terminal based on the target dataset. The approval instruction indicates that the main pump system meets the preset safe operation conditions. In response to receiving the approval instruction, the operation and maintenance procedures and overhaul operation manual for the reactor coolant main pump are revised and incorporated into the standardized operation and maintenance process.

2. The control method for canceling active venting of the reactor coolant main pump according to claim 1, characterized in that, The vacuuming operation of the primary loop system of the nuclear power plant specifically includes: A vacuum pump is used to pump the pressure of the primary loop system to a first preset pressure threshold and maintain the pressure for a preset time in order to perform a system sealing test. After completing the system sealing test, continue to pump vacuum until the absolute pressure of the primary loop system reaches the second preset pressure threshold. After the absolute pressure of the primary loop system reaches the second preset pressure threshold, the vacuum pump is switched to automatic control mode.

3. The control method for canceling active venting of the reactor coolant main pump according to claim 2, characterized in that, The first preset pressure threshold is 0.6 bar.a to 0.9 bar.a.

4. The control method for canceling active venting of the reactor coolant main pump according to claim 2, characterized in that, The preset time is 10 to 20 minutes.

5. The control method for canceling active venting of the reactor coolant main pump according to claim 2, characterized in that, The second preset pressure threshold is 0.1 bar.a to 0.3 bar.a.

6. The control method for canceling active venting of the reactor coolant main pump according to claim 2, characterized in that, The automatic control mode includes: setting the inlet pressure start / stop threshold of the vacuum pump; the vacuum pump automatically starts when the absolute pressure of the primary loop system is higher than 0.24 bar.a; and the vacuum pump automatically stops when the absolute pressure of the primary loop system is lower than 0.155 bar.a.

7. The control method for canceling active venting of the reactor coolant main pump according to claim 2, characterized in that, The primary loop system, after vacuuming, is filled with water and static venting is performed, specifically including: Water is added to the primary loop system after vacuuming is completed. When the voltage regulator liquid level reaches 95%, vacuuming and water filling are stopped, and then static venting is carried out on the primary loop system.

8. The control method for canceling active venting of the reactor coolant main pump according to claim 1, characterized in that, In response to receiving the approval instruction, the reactor coolant main pump operation and maintenance procedures and overhaul operation manual are revised and incorporated into the standardized operation and maintenance process, which then includes: The target dataset is stored in a long-term operational database to establish an operational reliability verification model for the reactor coolant main pump.

9. A control device for canceling active venting of the reactor coolant main pump, characterized in that, A control method for canceling active venting of the reactor coolant main pump according to any one of claims 1 to 8, the control device comprising: Vacuum module (110) is used to perform vacuuming operations on the primary loop system of a nuclear power plant; The static exhaust module (111) is used to fill the primary loop system with water after the vacuum has been completed and to carry out static exhaust. The monitoring and control module (112) is used to monitor the final gas content of the primary loop system. If the final gas content meets the preset conditions, the low-pressure safety injection is controlled to operate in SI mode. The start-up module (113) directly starts the main pump after the low-pressure injection is running in the SI mode, in order to replace the active venting operation.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the control method for canceling active venting of the reactor coolant main pump as described in any one of claims 1 to 8.

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