Nuclear power station temperature control rod system fault diagnosis method, device, equipment and medium

Abstract

The invention discloses a nuclear power station temperature control rod system fault diagnosis method, device, equipment and medium, and the method comprises the steps: independently generating a temperature setting value based on a secondary loop load, and carrying out the cross verification of the temperature setting value and the measured temperature of a primary loop; when it is detected that the temperature deviation is continuously positive and the control rod is abnormally inserted, an intervention program is executed immediately to stop the insertion action, and then the problem that in the prior art, the control rod is abnormally inserted due to instrument drifting is solved through a double-layer diagnosis mechanism of multi-path signal cross comparison and path-by-path isolation positioning. The defect that a control system of a traditional nuclear power station unit adopting a temperature control rod depends on fault signals in one direction is overcome.

Description

Technical Field

[0001] This invention relates to the field of nuclear power plant operation control technology, and in particular to a method, device, equipment and medium for fault diagnosis of a nuclear power plant temperature control rod system. Background Technology

[0002] In existing nuclear power plant units employing temperature control rods, the temperature control rod system relies entirely on three coupled input signals for closed-loop control. These three signals refer to the primary loop temperature instruments, the secondary loop load instruments, and the primary loop nuclear power instruments. When any instrument drifts or malfunctions, the control system cannot identify the erroneous signal; instead, it generates incorrect control commands based on this, continuously driving the control coil to lower the control rod. This one-way dependency mechanism is a fatal flaw, amplifying instrument errors into control actions, ultimately forcing the control rod to lower to the critical depth, triggering core flux distortion and forcing a reactor shutdown. Therefore, a fault diagnosis method for nuclear power plant temperature control rod systems is urgently needed to address the problem of abnormal temperature control rod lowering in existing nuclear power plant units employing temperature control rods when instruments drift or malfunction. Summary of the Invention

[0003] The embodiments of the present invention provide a method, apparatus, equipment and medium for fault diagnosis of a nuclear power plant temperature control rod system, which aims to solve the problem of abnormal insertion of temperature control rods in nuclear power plant units that use temperature control rods when instruments drift or malfunction.

[0004] In a first aspect, embodiments of the present invention provide a fault diagnosis method for a nuclear power plant temperature control rod system, applicable to nuclear power plant units employing temperature control rods. The method includes: generating a temperature setpoint based on secondary loop load measurements and obtaining the measured average temperature of the primary loop; calculating the temperature deviation between the temperature setpoint and the measured average temperature of the primary loop; determining a fault in the temperature control rod control system when the temperature deviation remains positive and the temperature control rod continues to drop, and executing a preset intervention program to stop controlling the temperature control rod to drop; performing cross-deviation comparison on multiple input signals of the temperature control rod control system to identify abnormal signal sources and locate the faulty loop.

[0005] Secondly, embodiments of the present invention also provide a fault diagnosis device for a nuclear power plant temperature control rod system, used to perform the fault diagnosis method for a nuclear power plant temperature control rod system as described above.

[0006] Thirdly, embodiments of the present invention also provide a computer device, the computer device including a memory and a processor connected to the memory; the memory is used to store a computer program; the processor is used to run the computer program stored in the memory to perform the steps of the above-described method for diagnosing faults in a nuclear power plant temperature control rod system.

[0007] Fourthly, embodiments of the present invention also provide a computer-readable storage medium storing a computer program, the computer program including program instructions, which, when executed by a processor, can implement the steps of the above-described method for diagnosing faults in a nuclear power plant temperature control rod system.

[0008] Compared with the prior art, the beneficial effects of the present invention are: In the technical solution of this invention, the fault diagnosis method for the temperature control rod system of a nuclear power plant cross-verifies the temperature setting value generated independently by the secondary loop load with the measured temperature of the primary loop. When a continuous positive temperature deviation is detected and the control rod is abnormally inserted, an intervention procedure is immediately executed to stop the insertion action. Then, through a two-layer diagnostic mechanism of cross-comparison of multiple signals and isolation and positioning of each channel, the problem of abnormal insertion of the control rod due to instrument drift in the prior art is solved, and the unidirectional dependence of the control system of the traditional nuclear power plant unit using temperature control rods on fault signals is broken. Attached Figure Description

[0009] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0010] Figure 1 A flowchart of a fault diagnosis method for a nuclear power plant temperature control rod system provided by the present invention; Figure 2 This is a first sub-flowchart of the fault diagnosis method for a nuclear power plant temperature control rod system provided by the present invention. Figure 3 This is a sub-flowchart of the second sub-flowchart of the fault diagnosis method for a nuclear power plant temperature control rod system provided by the present invention; Figure 4 The third sub-flowchart of the fault diagnosis method for nuclear power plant temperature control rod system provided by the present invention; Figure 5 The fourth sub-flowchart of the fault diagnosis method for the temperature control rod system of a nuclear power plant provided by the present invention; Figure 6 The fifth sub-flowchart of the fault diagnosis method for nuclear power plant temperature control rod system provided by the present invention; Figure 7 The sixth sub-flowchart of the fault diagnosis method for nuclear power plant temperature control rod system provided by the present invention; Figure 8 A schematic block diagram of a unit of the fault diagnosis device for a nuclear power plant temperature control rod system provided by the present invention; Figure 9 A schematic block diagram of a computer device provided for an embodiment of the present invention. Detailed Implementation

[0011] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0012] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0013] It should also be understood that the terminology used in this specification is for the purpose of describing embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0014] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0015] This invention addresses the problem of abnormal temperature control rod insertion in nuclear power plant units employing temperature control rods when instrument drift or malfunction occurs. It discloses a fault diagnosis method for nuclear power plant temperature control rod systems, applicable to units using temperature control rods. The embodiments of this invention are illustrated based on the CPR1000 nuclear power unit for ease of explanation. The three loops involved in this invention specifically refer to the reactor coolant system of a nuclear power plant, namely, three physically independent and structurally symmetrical parallel coolant sub-channels within the primary loop. The design of these three loops aims to achieve highly reliable heat removal and system redundancy. The primary loop is a general term referring to the entire reactor coolant circulation system constituted by the aforementioned three coolant loops. The secondary loop is a completely independent system that exchanges heat with the primary loop through a steam generator; its function is to generate steam to drive the turbine for power generation. The first loop, second loop, and third loop mentioned in this invention all refer to these three refrigerant channels within the primary loop. Three temperature observation points are set up in each of the three loops mentioned above, designated MT1, MT2, and MT3 on the diagnostic interface, respectively. Each temperature observation point is equipped with a temperature measuring instrument. In the secondary loop, there are three redundant load measuring points, designated GRE1, GRE2, and GRE3 on the diagnostic interface, respectively. Each redundant measuring point is equipped with a pipeline-type physical pressure transmitter. The fault diagnosis system is a dedicated device independent of the nuclear power plant's main control system. It automatically diagnoses whether the temperature control rod control system has faults and provides intervention and location information. Protective temperature instruments are temperature sensing and transmitting devices installed at critical locations in the reactor coolant system, whose measurement signals are specifically used for reactor safety protection. The hot end refers to the section of main piping extending from the reactor pressure vessel outlet to the steam generator inlet. At this location, the coolant has just flowed out of the core, absorbing the enormous heat generated by nuclear fission, and therefore has the highest temperature and pressure within the system. The cold end refers to the two sections of main piping extending from the steam generator outlet to the main pump inlet, and from the main pump outlet to the reactor pressure vessel inlet. At this location, the coolant has already flowed through the steam generator, transferring most of its heat to the feedwater in the secondary loop. Therefore, its temperature is significantly lower than that of the hot end, making it the relatively cooler part of the entire primary loop.

[0016] In the CPR1000 nuclear power unit, secondary loop steam pressure data is collected via GME701 / 702 / 703MP probes, independent of the temperature control rod control system. This data measurement point is represented as GRE474KMT on the diagnostic interface of the unit system control interface. Protective temperature instruments located in the three reactor loops collect the cold / hot end temperatures RCP030 / 033MT, RCP045 / 048MT, and RCP057 / 030MT in real time. These data measurement points are represented as RCP611KMX, RCP615KMX, and RCP619KMX on the diagnostic interface of the unit system control interface. The overall output status or diagnostic status of the temperature control rod control system is represented as RGL405KM on the diagnostic interface of the unit system control interface. The manual switching switch is represented as RCP481KC on the diagnostic interface of the unit system control interface. Reference Figures 1 to 7 The method includes the following steps: S110. Generate temperature setting values ​​based on the load measurement values ​​of the second loop, and obtain the measured average temperature of the first loop; S120. Calculate the temperature deviation between the temperature set value and the measured average temperature of the first loop. S130. When the temperature deviation is continuously positive and the temperature control rod continues to be inserted, it is determined that there is a fault in the temperature control rod control system, and a preset intervention program is executed to stop controlling the temperature control rod to be inserted. S140. Perform cross-deviation comparison on the multiple input signals of the temperature control rod control system to identify abnormal signal sources and locate faulty circuits.

[0017] Secondary loop steam pressure data is acquired using a GME probe independent of the temperature control rod control system and converted into a percentage load measurement. A GME probe is a steam pressure measuring instrument independent of the main control system, used for secondary loop load measurement. Its signal channel is isolated from the main control system to obtain objective secondary loop load data for calculating the temperature setpoint. Based on this load measurement, the temperature setpoint, i.e., the ideal operating temperature, is calculated using a pre-defined thermodynamic conversion model, such as a steam pressure-temperature mapping function. Simultaneously, the cold / hot end temperatures are acquired in real time by protective temperature instruments deployed in the three loops of the reactor. The arithmetic mean of the loop measurements is taken to obtain the measured average temperature of the primary loop. This step ensures the correspondence between the temperature setpoint and the secondary loop load, providing a basis for subsequent temperature deviation calculations.

[0018] The primary loop temperature is measured and its average value is obtained through primary loop temperature instruments. These instruments are installed on the reactor pressure vessel, steam generator, main pump, pressurizer, and their corresponding piping to monitor the primary loop temperature in real time. Multiple temperature measurements are obtained by collecting real-time temperatures from multiple temperature measurement points at the cold / hot ends of each loop using protective temperature instruments located in multiple coolant loops. These multiple temperature measurements are then averaged to obtain the primary loop average temperature. A temperature measurement point refers to the measurement location of the protective temperature instruments located in multiple coolant loops of the reactor, used to collect real-time temperatures; its signal is independent of the main control system. The temperature deviation between the generated temperature setpoint and the primary loop average temperature is calculated using a distributed control system. By continuously monitoring the temperature deviation, if the temperature deviation remains positive and the temperature control rod continues to descend, it indicates a significant overcooling in the primary loop. If the temperature control rod is still descending, it is determined that the temperature control rod control system may be faulty.

[0019] Once a fault is detected in the temperature control rod control system, a preset intervention procedure is immediately executed. Specific steps include switching the temperature control to manual mode, stopping the temperature control rod's downward movement, and restoring it to its initial position to eliminate any impact on the reactor. This step ensures that rapid action can be taken to prevent the temperature control rod from dropping too low, thereby protecting the safe operation of the reactor. The monitoring of the temperature control rod's step count is performed by the rod position indicator, indicated as RGL013 / 014QM on the diagnostic interface of the unit system control interface.

[0020] Cross-deviation comparison is performed on the multiple input signals of the temperature control rod control system to identify abnormal signal sources. Cross-deviation comparison refers to a diagnostic method that compares the multiple redundant input signals of the temperature control rod control system to identify inconsistencies. Specifically, this includes comparing the primary loop temperature measurements of different loops; comparing the secondary loop load measurements of different load measurement systems; and comparing the primary loop nuclear power measurements of multiple nuclear power measurement channels. The multiple input signals of the temperature control rod control system include three input signals: the primary loop control temperature instrument, the secondary loop load measurement instrument, and the primary loop nuclear power measurement instrument. Specifically, when the primary loop temperature measurement value of any loop is compared with the maximum value of the temperature measurements of the other two loops, if the deviation of a single temperature measurement value from the maximum value of the remaining temperature measurements is greater than 2°C, the temperature signal of that loop is determined to be abnormal and highlighted in red on the unit system control interface. When any secondary loop load measurement value is compared with an independent load reference value calculated based on the GME probe, if the deviation of two or more load measurement channels is greater than 3%, the load measurement system is determined to be abnormal and highlighted in red on the unit system control interface. When any nuclear power measurement value is compared with the maximum value of the other three nuclear power measurements, if the deviation of a single nuclear power measurement value from the maximum value of the remaining nuclear power measurements is greater than 2%, the channel corresponding to that nuclear power measurement value is determined to be abnormal, and it is highlighted in red on the unit system control interface. Highlighting in red means that the corresponding signal source or area is highlighted in red on the diagnostic interface of the unit system control interface to indicate an alarm. The load value measured by the GME probe is represented as GRE474KMT on the diagnostic interface of the unit system control interface. The nuclear power of each nuclear power measurement point is represented as RGL424 / 448 / 460 / 472MY on the diagnostic interface of the unit system control interface, respectively. Based on the above specific steps, abnormal input signals can be identified from the diagnostic interface of the unit system control interface, thereby initially locating the source of the fault.

[0021] In one embodiment, the fault diagnosis method for the nuclear power plant temperature control rod system further includes: S150. When the abnormal signal source cannot be identified, the faulty circuit is located by isolating the input signals one by one.

[0022] When, after performing cross-bias comparisons of multiple input signals, all comparison results do not exceed the preset deviation thresholds—for example, the deviations between the temperature measurements of the three loops are all ≤2℃; among the deviations of each GRE load channel value from the GME reference value, no two or more simultaneously exceed 3%; and the deviations between each nuclear power measurement value are all ≤2%—although the main diagnostic logic has determined that there is a fault in the temperature control rod control system, no obviously abnormal signal source has been found through internal signal cross-comparison. This indicates that the fault may not be caused by a significant drift or complete failure of a particular instrument. The GME reference value is the load value calculated from the secondary loop steam pressure measured by the GME probe.

[0023] When the abnormal signal source cannot be clearly identified through the aforementioned cross-deviation comparison, the faulty loop is further located by isolating the input signals one by one. Specifically, when the cross-deviation comparison cannot locate the abnormal signal source, a physical isolation operation is performed. The RCP481KC switch is set to the first position to shield the first loop temperature signal, and the display status of the RGL405KM is monitored. If the rod position control returns to normal, the first loop is determined to be faulty. The so-called first loop temperature signal refers to the coolant temperature measurement signal of the first loop in a circuit, which is collected by the temperature instrument for protection and / or control of the first loop and transmitted to the temperature control rod control system as an electrical signal used to calculate the temperature status of the loop. Setting the RCP481KC to the first position indicates that the temperature gauges RCP035MT / RCP032MT of the first loop are removed from the temperature control rod control system. If the temperature control rod control system returns to normal, it indicates that the temperature gauges RCP035MT / RCP032MT of the first loop are faulty. Similarly, setting RCP481KC to the second position and the RGL405KM display returning to normal indicates the anomaly is in the second loop; setting RCP481KC to the third position and the RGL405KM display returning to normal indicates the anomaly is in the third loop; when RCP481KC is in the fourth position, the fault source can be ruled out as the temperature signal loop of any loop, indicating the anomaly may be in the turbine load signal processing loop or the nuclear power signal processing loop. At this point, the diagnostic scope narrows to the processing stages of the other two critical input sources of the temperature control rod control system, meaning the fault may be in the turbine load signal or primary loop nuclear power signal processing loop. To definitively distinguish between these two, a secondary verification can be performed by switching another dedicated isolating switch RGL401KC. If the system returns to normal after switching RGL401KC, the fault is in the nuclear power signal processing loop; if it remains abnormal, the fault is in the turbine load signal processing loop. This method of isolating each loop sequentially further confirms the specific faulty loop, providing maintenance personnel with clear fault diagnosis information, thereby quickly repairing the fault and restoring the system to normal operation.

[0024] In one embodiment, step S110 includes: S111. Obtain the second-loop load data through a second-loop load measuring instrument independent of the temperature control rod control system; S112. Calculate the temperature setpoint representing the ideal operating condition based on the dual-loop load data; S113. Obtain real-time measurement values ​​of protective temperature instruments arranged in multiple loops of the reactor; S114. Calculate the average value of the temperature measurement values ​​of each loop based on the real-time measurement values, and perform average processing on each of the average values ​​to obtain the measured average temperature of the first loop.

[0025] In the CPR1000 nuclear power unit, independently installed GME-type probes are used as secondary loop load measurement instruments. These instruments are not electrically connected to the temperature control rod control system. Three GME probes, GME701 / 702 / 703MP, are installed in the turbine inlet pipe. After processing, the data is displayed as the corresponding data measurement point GRE474KMT on the diagnostic interface of the unit system control interface to collect secondary loop load data in real time.

[0026] Using the acquired secondary load data, a pre-defined algorithm is used to calculate the temperature setpoint representing the ideal operating condition. The specific algorithm can employ a linear regression model or a neural network model, trained based on historical data, to calculate the temperature setpoint in real time. This temperature setpoint calculation ensures that temperature values ​​conforming to the ideal operating condition can be generated under different load conditions, providing an accurate reference for subsequent temperature deviation calculations.

[0027] Protective temperature instruments are installed in multiple loops of the reactor to monitor the temperature of each loop in real time. These protective temperature instruments are physically isolated from the temperature control rod control system; that is, although they measure the same physical quantity, they serve different systems and have completely independent signal channels, thus ensuring measurement independence. These temperature instruments are installed on the reactor pressure vessel, steam generator, main pump, pressurizer, and their corresponding piping, ensuring coverage of all critical parts of the reactor, i.e., the specific physical location of each temperature measurement point. The real-time measurements recorded by each temperature instrument are transmitted to the central control room through a data acquisition system, ensuring the real-time nature and accuracy of the data. Specific temperature measurement points include the cold and hot ends of the reactor, and the temperature measurement values ​​for each loop are obtained through multiple temperature measurement points.

[0028] The average temperature value of each loop is calculated from the real-time measurements obtained from the temperature instruments used for protection in each loop. Specifically, for each loop, real-time measurements from multiple temperature measurement points are taken, and the average of these measurements is calculated. For example, the average temperature of RCP030MT and RCP033MT is represented as RCP611KM on the diagnostic interface of the unit system control interface.

[0029] Specifically, for the fault diagnosis system used in the fault diagnosis method of this invention, the steam pressure value measured by the GME system is first converted into the current percentage load of the secondary loop based on the thermodynamic balance relationship between the primary and secondary loops of the nuclear power plant. The GME system is a monitoring system composed of multiple GME probes. Then, based on this percentage load value, a load-temperature comparison table pre-installed in the fault diagnosis system is consulted to obtain the ideal average temperature of the primary loop coolant matching the current load, i.e., the temperature setpoint.

[0030] Simultaneously, the fault diagnosis system executes the step of acquiring the measured average temperature of the primary loop. Real-time measurements of the hot and cold ends of the protection-grade temperature measuring instruments located in the first, second, and third loops of the reactor are acquired. For each independent coolant loop, the average temperature of that loop is first calculated based on its own real-time hot and cold end measurements. After obtaining the average temperatures of the three loops, these three values ​​are averaged to obtain a final measured average temperature that comprehensively and accurately reflects the actual thermal state of the entire primary loop. This process, through multi-point measurement and redundant calculation, greatly improves the fault tolerance and reliability of the measured data.

[0031] The measured average temperature of the primary loop obtained through this step, compared with the existing technology that directly takes the measured value of the control instrument and is easily affected by instrument drift, eliminates single-point fault errors and provides a solid foundation for subsequent temperature deviation calculation and fault diagnosis.

[0032] In one embodiment, step S130 includes: S131. When the temperature deviation is continuously positive, monitor the real-time operation status of the temperature control rod. S132. When the temperature control rod is detected to be performing a continuous downward insertion action, a fault judgment signal for the temperature control rod control system is generated. S133. Based on the fault determination signal, switch the temperature control mode to manual operation mode and terminate the insertion drive command of the temperature control rod. S134. Send an upward drive command to the control coil of the temperature control rod, the upward drive command being used to instruct the control coil to return the temperature control rod to a safe initial position.

[0033] By monitoring the temperature deviation value in real time, it is determined whether it remains positive. The temperature deviation value is calculated by subtracting the temperature setpoint from the average measured temperature of the primary loop. When the temperature deviation value remains positive, it indicates a significant overcooling in the primary loop. At this time, the fault diagnosis system automatically initiates real-time monitoring of the temperature control rod's operational status. The real-time operational status of the temperature control rod is obtained by monitoring the feedback signal from the stepper motor via the rod position indicator. The stepper motor drives the temperature control rod to move up and down. After the rod position indicator uploads the electrical signal representing the actual physical position of the temperature control rod, the status monitoring module in the temperature control rod control system records the control rod's movement commands and actual position in real time.

[0034] While monitoring a persistently positive temperature deviation, the fault diagnosis system further monitors the real-time operational status of the temperature control rod. If the temperature control rod is continuously performing a downward insertion motion for a period of time, the fault diagnosis system generates a fault determination signal for the temperature control rod control system. Specifically, within a set time period, the position of the temperature control rod continuously moves in the insertion direction without any sign of stopping or rising. When the above conditions are met, the fault diagnosis system generates a fault determination signal and triggers subsequent intervention measures based on the fault determination signal.

[0035] Upon generating a fault diagnosis signal, the fault diagnosis system immediately switches the temperature control mode of the temperature control rod control system from automatic to manual operation. Simultaneously with the switch to manual operation, the system immediately terminates the insertion drive command sent to the control coil. By terminating the insertion drive command, the system prevents the temperature control rod from continuing to insert, thereby protecting the safe operation of the reactor.

[0036] After switching to manual operation mode and terminating the downward insertion drive command, the operator manually sends a lift command to the control coil to return the temperature control rod to its safe initial position. Manual operation is required for safety reasons; any critical operation necessitates manual confirmation. The temperature control rod control system generates a lift command and sends it to the control coil via the control command module. The fault diagnosis system automatically switches to manual mode and terminates the downward insertion command to immediately contain the fault, while simultaneously issuing clear intervention suggestions to the operator, who then manually performs the lift operation after assessment. Upon receiving the lift command, the control coil drives the temperature control rod to gradually return to its safe initial position. The safe initial position refers to the position the temperature control rod should be in under normal operating conditions, typically a preset safety reference position.

[0037] This scheme ensures that in the event of a failure, measures can be taken quickly to prevent the temperature control rods from dropping too low, thereby protecting the safe operation of the reactor.

[0038] In one embodiment, step S140 includes: S141. Compare the deviations of the multiple measurement signals from the primary loop temperature instrument and record the result as the first comparison. S142. Compare the deviations of the multiple load signals of the dual-loop load measuring instrument, and record the result as the second comparison result. S143. Compare the deviations of the multiple power signals of the primary loop nuclear power instrument and record it as the third comparison result. S144. When any of the comparison results of the first comparison result, the second comparison result, and the third comparison result exceeds a preset deviation threshold, the corresponding signal source is marked as abnormal. The preset deviation threshold includes a preset temperature deviation threshold, a preset relative deviation threshold, and a maximum power deviation threshold.

[0039] The deviation of multiple measurement signals from the primary loop temperature instruments is compared. These multiple measurement signals are electrical signals characterizing the average coolant temperature of each of the three independent coolant loops in the reactor coolant system, such as the first, second, and third loops, collected by protective temperature instruments. The raw temperature values ​​at the loop ends are collected by the protective temperature instruments, and the average temperature of any loop is calculated. The loop end temperature specifically refers to the real-time coolant temperature collected by temperature sensors installed at key locations in each coolant loop of the reactor. Then, the target loop temperature is compared with the maximum value of the other two loop temperatures to obtain the temperature deviation value. The target loop temperature is the average temperature of the currently selected loop being tested. Assuming a preset temperature deviation threshold of 2°C, if the deviation exceeds 2°C, the target loop temperature signal is marked as abnormal, and the corresponding loop identifier turns red on the diagnostic interface of the unit system control interface.

[0040] Deviation comparison is performed on multiple load signals from the secondary loop load measurement instruments. Multiple load signals refer to electrical signals representing the current turbine power or steam pressure generated by multiple redundant and independent load measurement channels in the secondary loop load measurement system. A measurement signal independent of the main temperature control bar control system is selected as a reliable reference, and the three redundant load signals used for temperature control in the main control system are used as the comparison objects. For example, using GME474KMT as the reference, single-channel GRE load calculations are performed on the three GRE load signals (GRE022 / 023 / 024MPY) to obtain the relative load deviation. Assuming a preset relative deviation threshold of 3%, if the relative load deviation obtained after comparing the values ​​of two or more GRE load channels with the GME reference value simultaneously exceeds the preset relative deviation threshold of 3%, the load measurement system is flagged as abnormal.

[0041] Deviation comparison is performed on the multiple power signals from the primary loop nuclear power instruments. These multiple power signals are electrical signals characterizing the total nuclear power of the reactor, acquired and processed by four independent redundant measurement channels. For the currently selected target channel, the real-time power measurements from the other three channels are compared, and the maximum value among these three is used as the benchmark for this comparison. If one channel malfunctions, its value will deviate from the other three normal channels. By comparing it with the maximum values ​​of the other three channels, this anomaly can be effectively detected. For example, for four nuclear power measurement channels, namely RGL424 / 448 / 460 / 472MY, the deviation of any one channel is compared with the real-time power measurements of the other three channels to obtain the maximum power deviation value. Assuming the preset maximum power deviation threshold is 2%, if the maximum power deviation value obtained by comparing any nuclear power measurement value with the maximum value of the other three nuclear power measurements exceeds the maximum power deviation threshold of 2%, that power channel is marked as abnormal.

[0042] The steps in this embodiment ensure that the source of the abnormal signal can be quickly identified when a fault occurs, providing accurate information for subsequent fault handling.

[0043] Furthermore, the steps in S140 include: S141a. The temperature measurement value of a single loop is compared with the maximum value of the temperature measurement values ​​of the remaining loops.

[0044] S142a. Compare the individual load measurement value with a preset independent load reference value.

[0045] To further improve the accuracy of temperature measurement comparison and fault identification, a step has been added to compare the temperature measurement value of a single loop with the maximum value among the temperature measurements of the remaining loops. The temperature measurement value for each loop is obtained from the primary loop temperature instrument. Assuming there are three temperature measurement points MT1, MT2, and MT3 in the primary loop, the temperature values ​​for MT1, MT2, and MT3 are obtained respectively. For each loop, the maximum value among the temperature measurements of the remaining loops is obtained. For example, for MT1, the maximum values ​​of MT2 and MT3 are obtained; for MT2, the maximum values ​​of MT1 and MT3 are obtained; and for MT3, the maximum values ​​of MT1 and MT2 are obtained. The temperature measurement value of each loop is compared with the maximum value of its corresponding remaining loop. For example, MT1 is compared with the maximum values ​​of MT2 and MT3, MT2 is compared with the maximum values ​​of MT1 and MT3, and MT3 is compared with the maximum values ​​of MT1 and MT2. The comparison results are recorded as the deviation of the temperature measurement value. If the deviation of the temperature measurement value of a single loop from its corresponding maximum value exceeds a preset deviation threshold, such as 2°C, the temperature measurement signal of that loop is marked as abnormal. In this way, any anomalies that may occur in the temperature measurements can be identified more accurately.

[0046] To further improve the comparison accuracy of load measurements and the accuracy of fault identification, a step of comparing individual load measurements with preset independent load reference values ​​has been added. The load value for each load measurement point is obtained from the secondary loop load measuring instruments. A load measurement point refers to a key sensing device installed on the main steam pipe of the secondary loop of the nuclear power plant, used to directly measure steam pressure and indirectly reflect reactor thermal power; that is, the location of its logic signal output in the temperature control rod control system. Assuming there are three load measurement points in the secondary loop, GRE1, GRE2, and GRE3, the load values ​​for GRE1, GRE2, and GRE3 are obtained respectively. The preset independent load reference value is a standard value set based on the normal operation data and historical experience of the nuclear power plant. This reference value can be a fixed value or a range. Each load measurement value is compared with the preset independent load reference value. For example, GRE1 is compared with the preset independent load reference value, GRE2 is compared with the preset independent load reference value, and GRE3 is compared with the preset independent load reference value. The comparison results are recorded as the deviation of the load measurement value. If a single load measurement deviates from a preset independent load reference value by more than a preset deviation threshold, the load measurement signal is marked as abnormal. In this way, possible anomalies in load measurements can be identified more accurately.

[0047] In one embodiment, step S150 includes: S151. Sequentially isolate the temperature signal input channels of each loop, and determine the signal loop where the fault is located based on the response status of the temperature control rod control system; S152. If the control system returns to normal after isolating any one of the multiple loop signals, then the fault is determined to be located in the corresponding isolated loop. S153. If the control system is still abnormal after isolating all loop signals, the fault is determined to be located in the nuclear power or load signal processing loop.

[0048] When the source of the abnormal signal cannot be identified, the faulty loop is located by isolating the input signals one by one. Specifically, physical isolation is achieved by manually setting the RCP481KC switch to the corresponding position, thus shielding the corresponding loop's temperature signal. The isolation status is highlighted on the diagnostic interface. Isolate the temperature signal input channel of one loop, such as the first loop, from the temperature control rod control system. Isolation can be achieved by disconnecting the temperature signal transmission line or setting the isolation mode in the temperature control rod control system. After isolating the temperature signal of one loop, monitor the response status of the temperature control rod control system. If the temperature control rod control system returns to normal, the fault is located in the temperature measurement signal transmission loop of the first loop. If the temperature control rod control system remains abnormal after isolating the temperature signal of one loop, continue isolating the temperature signal input channel of another loop, such as the second loop. If the temperature control rod control system remains abnormal after isolating the temperature signal of the second loop, continue isolating the temperature signal input channel of another loop, such as the third loop. Repeat the above steps, monitoring the response status of the temperature control rod control system. During the process of isolating each loop's temperature signal input channel, if the temperature control rod control system returns to normal after isolating a certain loop's signal, the fault can be determined to be located in the corresponding loop. Once the temperature control rod control system is found to have returned to normal, further isolation operations should be stopped immediately, and the information of the faulty loop should be recorded.

[0049] If the temperature control bar control system remains abnormal after isolating all loop temperature signals, the fault can be determined to be in the nuclear power signal processing loop or the load signal processing loop. Isolate the input channel of the nuclear power signal processing loop from the temperature control bar control system. Isolation can be achieved by disconnecting the power signal transmission line or setting an isolation mode in the temperature control bar control system. After isolating the nuclear power signal, monitor the response status of the fault diagnosis system. If the temperature control bar control system returns to normal, the fault is in the nuclear power signal processing loop. If the temperature control bar control system remains abnormal after isolating the nuclear power signal, continue isolating the input channel of the load signal processing loop. If the temperature control bar control system returns to normal after isolating the load signal, the fault is in the load signal processing loop. If the temperature control bar control system remains abnormal after isolating all signals, further investigation of hardware or software faults in the fault diagnosis system itself is required.

[0050] This embodiment describes a method for locating faulty circuits by isolating input signals one by one when the source of an abnormal signal cannot be identified. These steps ensure that the fault source can be quickly located when a fault occurs, providing accurate information for fault handling.

[0051] In one embodiment, the steps of the fault diagnosis method for a nuclear power plant temperature control rod system further include: S160. Based on the identified abnormal signal source or fault circuit, trigger a maintenance command and generate a fault location report.

[0052] Once the fault diagnosis system identifies an abnormal signal source or locates a faulty circuit, the maintenance response engine immediately triggers a closed-loop handling process. First, a structured maintenance work order is automatically created through the integrated work order management system, including the faulty equipment code, fault type label, handling deadline, and linked to standard operating procedures. Simultaneously, an electronic instruction with a biometric signature is pushed to the maintenance team's mobile terminal, triggering the allocation of the specified sensor model from the spare parts warehouse. Maintenance instructions can be sent to maintenance personnel in various ways, such as through a central monitoring system, mobile devices, or email, ensuring that maintenance personnel can receive and process these instructions promptly.

[0053] To further improve the efficiency and accuracy of fault handling, the fault diagnosis system automatically generates a fault location report. The system records all fault-related information, including but not limited to the time and location of the fault, specific measurements, deviations, and identification methods. The generated fault location report is archived within the system for subsequent fault analysis and tracing. Archived reports can be stored in a central database for access by maintenance personnel and management.

[0054] Figure 8 This is a schematic block diagram of a fault diagnosis device 600 for a nuclear power plant temperature control rod system provided in an embodiment of the present invention. Figure 8 As shown, corresponding to the above-described method for diagnosing faults in a nuclear power plant temperature control rod system, the present invention also provides a nuclear power plant temperature control rod system fault diagnosis device 600. This nuclear power plant temperature control rod system fault diagnosis device 600 includes a unit for performing the above-described method for diagnosing faults in a nuclear power plant temperature control rod system, and the device can be configured in a desktop computer, tablet computer, smartphone, or other terminal.

[0055] Specifically, please refer to Figure 8 The fault diagnosis device 600 for the temperature control rod system of the nuclear power plant includes: The parameter acquisition unit 610 is used to generate a temperature setting value based on the load measurement value of the second loop and to acquire the measured average temperature of the first loop. The deviation calculation unit 620 is used to calculate the temperature deviation between the temperature setting value and the measured average temperature of the first loop. The fault judgment unit 630 is used to determine that there is a fault in the temperature control rod control system when the temperature deviation is continuously positive and the temperature control rod continues to be inserted, and to execute a preset intervention program to stop controlling the temperature control rod to be inserted. The abnormal signal source identification unit 640 is used to perform cross-deviation comparison on the multiple input signals of the temperature control rod control system to identify the abnormal signal source and locate the fault circuit.

[0056] In one embodiment, the nuclear power plant temperature control rod system fault diagnosis device 600 further includes: The fault circuit location unit is used to locate the fault circuit by isolating the input signals one by one when the abnormal signal source cannot be identified.

[0057] In one embodiment, the first parameter acquisition unit 610 includes: The first data acquisition unit is used to acquire second-loop load data through a second-loop load measuring instrument that is independent of the temperature control rod control system. The second data acquisition unit is used to calculate the temperature setpoint characterizing the ideal operating condition based on the dual-loop load data. The third data acquisition unit is used to acquire real-time measurement values ​​of protective temperature instruments arranged in multiple loops of the reactor. The average temperature acquisition unit is used to calculate the average value of the temperature measurement values ​​of each loop based on the real-time measurement values, and to perform average processing on each of the average values ​​to obtain the measured average temperature of the first loop.

[0058] In one embodiment, the fault determination unit 630 includes: The first-level judgment unit is used to monitor the real-time operation status of the temperature control rod when the temperature deviation is continuously positive. The second-level judgment unit is used to generate a fault judgment signal for the temperature control rod control system when the temperature control rod is detected to be performing a continuous downward insertion action. The control mode switching unit is used to switch the temperature control mode to manual operation state based on the fault judgment signal and terminate the insertion drive command of the temperature control rod. A reset execution unit is used to send an upward drive command to the control coil of the temperature control rod, the upward drive command being used to instruct the control coil to return the temperature control rod to a safe initial position.

[0059] In one embodiment, the abnormal signal source identification unit 640 includes: The first comparison result unit is used to compare the deviations of multiple measurement signals from the primary loop temperature instrument, and is denoted as the first comparison result. The second comparison result unit is used to compare the deviations of the multi-channel load signals of the dual-loop load measuring instrument, and the result is recorded as the second comparison result. The third comparison result unit is used to compare the deviations of multiple power signals from the primary loop nuclear power instrument, and is denoted as the third comparison result. An abnormal signal source marking unit is used to mark the corresponding signal source as abnormal when any of the comparison results of the first comparison result, the second comparison result, and the third comparison result exceeds a preset deviation threshold. The preset deviation threshold includes a preset temperature deviation threshold, a preset relative deviation threshold, and a maximum power deviation threshold.

[0060] In one embodiment, the abnormal signal source identification unit 640 includes: A temperature measurement comparison unit is used to compare the temperature measurement value of a single loop with the maximum value among the temperature measurement values ​​of the remaining loops.

[0061] A load measurement comparison unit is used to compare a single load measurement value with a preset independent load reference value.

[0062] In one embodiment, the fault loop location unit includes: The isolation judgment unit is used to sequentially isolate the temperature signal input channels of each loop and determine the signal loop where the fault is located based on the response status of the temperature control rod control system. The first fault location unit is used to determine that the fault is located in the corresponding isolated loop if the control system returns to normal after isolating any of the multiple loop signals. The second fault location unit is used to determine whether the fault is located in the nuclear power or load signal processing loop if the control system is still abnormal after isolating all loop signals.

[0063] In one embodiment, the nuclear power plant temperature control rod system fault diagnosis device 600 further includes: The fault location report generation unit is used to trigger maintenance instructions and generate a fault location report based on the identified abnormal signal source or the fault circuit.

[0064] The aforementioned nuclear power plant temperature control rod system fault diagnosis device 600 can be implemented as a computer program, which can, for example, Figure 9 It runs on the computer device shown.

[0065] Please see Figure 9 , Figure 9This is a schematic block diagram of a computer device 500 provided in an embodiment of this application. The computer device 500 can be a terminal or a server. The terminal can be an electronic device with communication functions, such as a desktop computer, tablet computer, or smartphone. The server can be a standalone server or a server cluster composed of multiple servers.

[0066] See Figure 9 The computer device 500 includes a processor 502, a memory, and a network interface 505 connected via a system bus 501. The memory may include a non-volatile storage medium 503 and internal memory 504.

[0067] The non-volatile storage medium 503 may store an operating system 5031 and a computer program 5032. The computer program 5032 includes program instructions that, when executed, cause the processor 502 to perform a fault diagnosis method for a nuclear power plant temperature control rod system.

[0068] The processor 502 provides computing and control capabilities to support the operation of the entire computer device 500.

[0069] The internal memory 504 provides an environment for the operation of the computer program 5032 in the non-volatile storage medium 503. When the computer program 5032 is executed by the processor 502, the processor 502 can execute a fault diagnosis method for a nuclear power plant temperature control rod system.

[0070] This network interface 505 is used for network communication with other devices. Those skilled in the art will understand that... Figure 9 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device 500 to which the present application is applied. The specific computer device 500 may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0071] The processor 502 is used to run a computer program 5032 stored in a memory to implement the steps of the above method.

[0072] It should be understood that in the embodiments of this application, the processor 502 may be a central processing unit (CPU), or it may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0073] It will be understood by those skilled in the art that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program includes program instructions and can be stored in a storage medium, which is a computer-readable storage medium. The program instructions are executed by at least one processor in the computer system to implement the process steps of the embodiments of the above methods.

[0074] Therefore, the present invention also provides a storage medium. This storage medium can be a computer-readable storage medium. The storage medium stores a computer program, wherein the computer program includes program instructions. When executed by a processor, the program instructions cause the processor to perform the steps of the above-described method.

[0075] The storage medium can be any computer-readable storage medium capable of storing program code, such as a USB flash drive, portable hard drive, read-only memory (ROM), magnetic disk, or optical disk.

[0076] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0077] In the several embodiments provided by this invention, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For example, the division of each unit is only a logical functional division, and there may be other division methods in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed.

[0078] The steps in the method of this invention can be adjusted, merged, or reduced in order according to actual needs. The units in the device of this invention can be merged, divided, or reduced according to actual needs. Furthermore, the functional units in the various embodiments of this invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0079] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, a terminal, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention.

[0080] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for fault diagnosis of a temperature control rod system in a nuclear power plant, characterized in that, Applied to nuclear power plant units employing temperature control rods, the method includes: The temperature setting value is generated based on the load measurement values ​​of the second loop, and the measured average temperature of the first loop is obtained. Calculate the temperature deviation between the temperature setpoint and the measured average temperature of the first loop; When the temperature deviation remains positive and the temperature control rod continues to descend, it is determined that there is a fault in the temperature control rod control system, and a preset intervention program is executed to stop controlling the descent of the temperature control rod. The multiple input signals of the temperature control rod control system are cross-biased to identify abnormal signal sources and locate faulty circuits.

2. The method for fault diagnosis of a nuclear power plant temperature control rod system according to claim 1, characterized in that, The method further includes: When the source of the abnormal signal cannot be identified, the faulty circuit is located by isolating the input signals one by one.

3. The method for fault diagnosis of a nuclear power plant temperature control rod system according to claim 1, characterized in that, The step of determining that the temperature control rod control system is faulty and executing a preset intervention program to stop controlling the temperature control rod from inserting when the temperature deviation remains positive and the temperature control rod continues to descend includes: When the temperature deviation remains positive, monitor the real-time operation status of the temperature control rod. When the temperature control rod is detected to be performing a continuous downward insertion action, a fault judgment signal is generated for the temperature control rod control system. Based on the fault determination signal, the temperature control mode is switched to manual operation mode, and the insertion drive command of the temperature control rod is terminated. A lift-up drive command is sent to the control coil of the temperature control rod, the lift-up drive command being used to instruct the control coil to return the temperature control rod to a safe initial position.

4. The method for fault diagnosis of a nuclear power plant temperature control rod system according to claim 1, characterized in that, The step of performing cross-deviation comparison on the multiple input signals of the temperature control rod control system to identify abnormal signal sources and locate faulty loops includes: The deviation of the multiple measurement signals from the primary loop temperature instrument is compared and recorded as the first comparison result. The deviation of the multiple load signals from the dual-loop load measuring instrument is compared and recorded as the second comparison result. The deviation of the multiple power signals from the primary loop nuclear power instrument is compared and recorded as the third comparison result. When any of the first comparison result, the second comparison result, and the third comparison result exceeds a preset deviation threshold, the corresponding signal source is marked as abnormal. The preset deviation threshold includes a preset temperature deviation threshold, a preset relative deviation threshold, and a maximum power deviation threshold.

5. The method for fault diagnosis of a nuclear power plant temperature control rod system according to claim 2, characterized in that, When the abnormal signal source cannot be identified, the step of locating the faulty circuit by isolating the input signals one by one includes: The temperature signal input channels of each loop are isolated in sequence, and the signal loop where the fault is located is determined according to the response status of the temperature control rod control system. If the control system returns to normal after isolating any one of the multiple loop signals, then the fault is determined to be located in the corresponding isolated loop. If the control system is still abnormal after isolating all loop signals, the fault is determined to be in the nuclear power or load signal processing loop.

6. The method for fault diagnosis of a nuclear power plant temperature control rod system according to claim 1, characterized in that, The steps of generating temperature setpoints based on the load measurements of the second loop and obtaining the measured average temperature of the first loop include: Second-loop load data is acquired using a second-loop load measuring instrument independent of the temperature control rod control system. The temperature setpoint representing the ideal operating condition is calculated based on the aforementioned dual-loop load data. Acquire real-time measurements from protective temperature instruments arranged in multiple loops of the reactor; The average temperature of each loop is calculated based on the real-time measurement values, and the average values ​​are then averaged to obtain the measured average temperature of the first loop.

7. The method for fault diagnosis of a nuclear power plant temperature control rod system according to claim 3, characterized in that, The step of performing cross-deviation comparison on the multiple input signals of the temperature control rod control system to identify abnormal signal sources further includes: The temperature measurement value of a single loop is compared with the maximum value of the temperature measurements of the remaining loops; The individual load measurement value is compared with a preset independent load reference value.

8. The method for fault diagnosis of a nuclear power plant temperature control rod system according to claim 1, characterized in that, Also includes: Based on the identified abnormal signal source or fault circuit, a maintenance command is triggered and a fault location report is generated.

9. A fault diagnosis device for a nuclear power plant temperature control rod system, characterized in that, A method for diagnosing faults in a nuclear power plant temperature control rod system as described in any one of claims 1 to 8.

10. A computer device, characterized in that, The computer device includes a memory and a processor connected to the memory; the memory is used to store a computer program; the processor is used to run the computer program stored in the memory to perform the steps of the method as described in any one of claims 1 to 8.

11. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, which includes program instructions that, when executed by a processor, can implement the steps of the method as described in any one of claims 1 to 8.

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