Method and system for real-time on-line monitoring and fault diagnosis of reactor rod position detector

Abstract

The present application belongs to the technical field of nuclear power plant, and particularly relates to a kind of reactor rod position detector real-time online monitoring and fault diagnosis method and system.The present application includes the following steps: S1, respectively acquisition rod position detector primary winding voltage signal and current signal, auxiliary coil voltage signal, and the voltage signal of measuring coil;S2, the signal of step S1 is carried out data filtering processing;S3, the data of step S2 after filtering processing is carried out data preprocessing, and feature parameter information is extracted;S4, the feature characteristic parameter of single rod position detector processed in step S3 is compared with threshold;S5, all rod position detector characteristic parameters processed in step S3 are grouped according to core layout, the same characteristic parameter in each group is compared, and 3σ principle is used for abnormal value detection.The present application realizes real-time monitoring of rod position detector operating state, and rapid identification and positioning under various fault conditions.

Description

Technical Field

[0001] This invention belongs to the field of nuclear power plant technology, specifically relating to a method and system for real-time online monitoring and fault diagnosis of reactor rod position detectors. Background Technology

[0002] In pressurized water reactor nuclear power plants, the control rod bundles are located inside a high-temperature, high-pressure pressure vessel, making direct measurement of their actual positions impossible. Currently, the most widely used measurement method utilizes the principle of electromagnetic induction, indirectly obtaining the actual positions of the control rods through rod position detectors. In nuclear power plants, the accuracy of the actual control rod positions is crucial to the safe operation and stable control of the reactor; and the accuracy of the measurement is inextricably linked to the electrical performance of the rod position detectors.

[0003] When control rod position detectors malfunction or degrade, it can lead to serious faults or accidents that severely impact reactor operation, such as signal loss, inaccuracy, or errors, thereby affecting reactor safety and economic efficiency. Conventional methods for testing the electrical performance of rod position detectors can only be performed manually offline during nuclear power plant overhauls or refueling, which is costly in terms of manpower and time, and also lacks the ability to predict faults in advance. Summary of the Invention

[0004] The technical problem solved by this invention is to provide a method and system for real-time online monitoring and fault diagnosis of reactor rod position detectors. This method overcomes the shortcomings of existing nuclear power plant rod position detectors, whose electrical performance can only be manually tested offline. With highly accurate and reliable state parameter measurement capabilities, it realizes real-time monitoring of the operating status of rod position detectors and rapid identification and location of various fault conditions. At the same time, it can also realize early warning of rod position detector performance degradation.

[0005] The technical solution adopted in this invention is as follows:

[0006] A method for real-time online monitoring and fault diagnosis of reactor rod level detectors, specifically including the following steps:

[0007] S1. Collect the voltage and current signals of the primary coil of the rod position detector, the voltage signal of the auxiliary coil, and the voltage signal of the measuring coil, respectively.

[0008] S2. Perform data filtering processing on the primary coil voltage signal, primary coil current signal, auxiliary coil voltage signal, and measurement coil voltage signal of each rod position detector collected by the signal sensor in step S1.

[0009] S3. Perform data preprocessing on the filtered data from step S2 to extract the primary coil resistance, inductance, amplitude, frequency, and phase characteristic parameters of each rod position detector.

[0010] S4. Perform threshold comparison on the characteristic parameters of the single rod detector processed in step S3. When the value exceeds the warning value, output the warning information; when the value exceeds the alarm value, output the alarm information.

[0011] S5. Group all the characteristic parameters of the rod detectors processed in step S3 according to the core arrangement, compare the same characteristic parameter in each group, and use the 3σ principle to detect outliers.

[0012] S6, combining the status monitoring and fault diagnosis results of the rod position detectors in S4 and S5, outputs the final status of each rod position detector.

[0013] In step S1, voltage and current sensors are installed on the power supply device of each rod position detector to collect the voltage signal and current signal of the primary coil and the voltage signal of the auxiliary coil of the rod position detector, respectively; a voltage sensor is installed on the measuring device of the rod position detector to collect the voltage signal of the measuring coil, respectively.

[0014] The method for extracting the resistance and inductance of the primary coil in the data preprocessing is as follows:

[0015] The measured voltage and current of the primary coil are V, respectively. 原边 and I 原边 The impedance of the coil is calculated as follows:

[0016]

[0017] Impedance value Z 原边 It should be a complex number, and the resistance and inductance information of the coil should be obtained according to the following formula:

[0018] Z 原边 =R 原边 +j(2πfL 原边 )

[0019] In the above calculation results, R 原边 This refers to the resistance information of the primary coil, L. 原边 This refers to the inductance information of the primary coil; where j is the imaginary unit and f is the power supply frequency.

[0020] The method for extracting the amplitude, frequency, and phase information of all coils in the data preprocessing is as follows:

[0021] The collected coil voltage signals are labeled as V. in and V in As signal V α The signal V is obtained using the Hilbert transform. β V obtained by Hilbert transform α and V βBy using Parker variation and average filtering, the signal V is obtained. d V q Then, the measured values ​​V of the signal amplitude, initial phase, and frequency are obtained. And f1, integrating over 2πf1, we get θ1; finally, Adding θ1 to θ2 yields the measured value of the input signal phase.

[0022] The process for outlier detection based on the 3σ principle is as follows:

[0023] S501. Calculate the mean and standard deviation of the data series to be tested;

[0024] S502. Compare whether the deviation of each value in the data column from the average value exceeds 3 times σ. If it exceeds 3 times σ, output a warning signal.

[0025] In step S6, if a certain rod position detector has neither a warning message nor an alarm message, it outputs a normal state.

[0026] A rod position detector that outputs an alarm status indicates that the device is faulty and needs to be replaced or repaired; a rod position detector that outputs a warning status indicates that the device can still operate, but there may be a risk of failure, requiring close monitoring or early replacement or repair; a rod position detector that outputs a normal status indicates that the device is operating normally and there is no potential risk.

[0027] A real-time online monitoring and fault diagnosis system for reactor rod level detectors includes:

[0028] Voltage and current sensors are used to collect the voltage and current signals of the primary coil and the auxiliary coil of the rod position detector, respectively. A voltage sensor is installed on the measuring device of the rod position detector to collect the voltage signals of the five sets of measuring coils.

[0029] The data filtering module performs data filtering processing on the primary coil voltage signal, primary coil current signal, auxiliary coil voltage signal, and 5 sets of measurement coil voltage signals of each rod position detector.

[0030] The data preprocessing module extracts the resistance and inductance of the primary coil of each rod position detector, as well as the amplitude, frequency, and phase characteristic parameters of all coils.

[0031] The threshold comparison module performs threshold comparisons on the characteristic parameters of a single rod-position detector.

[0032] Early warning and alarm module.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] (1) The present invention provides a method and system for real-time online monitoring and fault diagnosis of reactor rod position detectors. Without changing the existing structure of the rod position detectors, it can assist nuclear power plant operators in automatically diagnosing and predicting various faults or accidents that may occur during system operation by simply adding relevant signal sensors and processing devices, and provide necessary support for operators to formulate response strategies.

[0035] (2) The present invention provides a method and system for real-time online monitoring and fault diagnosis of reactor rod position detectors. By collecting the current and voltage signals of the rod position detectors and combining them with algorithm analysis, the key characteristic parameters such as resistance and inductance of the object are extracted, the changing trends of the key characteristic parameters are compared and analyzed, and the data is identified by intelligent algorithms to realize online monitoring of its status, thereby realizing online diagnosis of faults.

[0036] (3) The present invention provides a method and system for real-time online monitoring and fault diagnosis of reactor rod position detectors. Through comparative analysis of historical and current data of key characteristic parameters, combined with intelligent algorithms, the lifespan can be estimated.

[0037] (4) The present invention provides a method and system for real-time online monitoring and fault diagnosis of reactor rod position detectors, which is applicable to all pressurized water reactor nuclear power plants that are in operation or under construction, and has a wide range of applications.

[0038] (5) The present invention provides a method and system for real-time online monitoring and fault diagnosis of reactor rod position detectors, which can significantly improve the time cost and manpower requirements of existing nuclear power plant operation and maintenance, and has significant economic benefits. Attached Figure Description

[0039] Figure 1 The present invention provides a flowchart of a method for real-time online monitoring and fault diagnosis of reactor rod position detectors;

[0040] Figure 2 : Schematic diagram of the signal acquisition settings for the rod position detector;

[0041] Figure 3 : A schematic diagram illustrating the extraction method of amplitude, frequency, and phase information of all coils in the data preprocessing module. Detailed Implementation

[0042] 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 embodiments of the present invention, and not all embodiments. 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.

[0043] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0044] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0045] Rod position detectors are important measuring devices in nuclear power plant reactors. When they malfunction or degrade, they will seriously threaten the safety and economy of the reactor.

[0046] In this embodiment, the rod position detector is applicable to a megawatt-class pressurized water reactor nuclear power plant. This type of power plant has a total of 69 rod position detectors, which measure the positions of 69 control rods. Each rod position detector consists of a primary coil, a pair of auxiliary coils, and five sets of A, B, C, D, and E measurement coils.

[0047] like Figure 1 As shown, this invention provides a real-time online monitoring and fault diagnosis method for reactor rod level detectors. This method acquires real-time signals from three types of coils (primary coil, auxiliary coil, and measuring coil) of each rod level detector, extracts key characteristic parameters, and achieves online monitoring and fault diagnosis based on their changes and trends. Specifically, it includes the following steps:

[0048] S1. Since only the primary coil of the rod position detector is powered during actual operation, its voltage and current signals can be directly acquired. The other coils are in open-circuit mode, and only their voltage data can be acquired. Therefore, voltage and current sensors are installed on the power supply device of each rod position detector, such as... Figure 2 As shown, the voltage and current signals of the primary coil and the auxiliary coil of the rod position detector are collected respectively; a voltage sensor is set on the measuring device of the rod position detector to collect the voltage signals of the five sets of measuring coils respectively.

[0049] S2. Perform data filtering processing on the primary coil voltage signal, primary coil current signal, auxiliary coil voltage signal, and A\B\C\D\E measurement coil voltage signal of each rod position detector collected by the signal sensor in step S1.

[0050] S3. Perform data preprocessing on the filtered data from step S2, and extract the primary coil resistance, inductance, amplitude, frequency, phase and other characteristic parameters of each rod position detector.

[0051] S301, the method for extracting the primary coil resistance and inductance in the data preprocessing is as follows:

[0052] The measured voltage and current of the primary coil are V, respectively. 原边 and I 原边 The impedance of the coil is calculated as follows:

[0053]

[0054] Impedance value Z 原边 It should be a complex number, and the resistance and inductance information of the coil can be obtained according to the following formula:

[0055] Z 原边 =R 原边 +j(2πfL 原边 )

[0056] In the above calculation results, R 原边 This refers to the resistance information of the primary coil, L. 原边 This refers to the inductance information of the primary coil; where j is the imaginary unit and f is the power supply frequency, which is 50Hz in this invention.

[0057] S302, The method for extracting the amplitude, frequency, and phase information of all coils in the data preprocessing is as follows:

[0058] The collected coil voltage signals are labeled as V. in and V in As signal V α The signal V is obtained using the Hilbert transform. β V obtained by Hilbert transform α and V β By using Parker variation and average filtering, the signal V is obtained. d V q Then, the measured values ​​V of the signal amplitude, initial phase, and frequency are obtained. Integrating f1 with respect to 2πf1 yields θ1. Finally, Adding θ1 to obtain the measured value θ2 of the input signal phase, the specific process is as follows: Figure 3 As shown.

[0059] S4. Perform threshold comparison on the characteristic parameters of the single rod detector processed in step S3. When the value exceeds the warning value, output the warning information; when the value exceeds the alarm value, output the alarm information.

[0060] S5. The characteristic parameters of the 69 rod-position detectors processed in step S3 are grouped according to the core layout. The same characteristic parameter in each group is compared, and the 3σ principle is used to detect outliers. The process is as follows:

[0061] S501. Calculate the mean and standard deviation of the data series to be tested;

[0062] S502. Compare whether the deviation of each value in the data column from the average value exceeds 3 times σ. If it exceeds 3 times σ, output a warning signal.

[0063] S6. Based on the status monitoring and fault diagnosis results of the rod position detectors in S4 and S5, output the final status of each rod position detector. If a rod position detector has neither warning information nor alarm information, output the normal status.

[0064] S7. A rod position detector that outputs an alarm status indicates that the equipment has malfunctioned and needs to be replaced or repaired; a rod position detector that outputs a warning status indicates that the equipment can still operate, but there may be a risk of failure, requiring close attention or early replacement or repair; a rod position detector that outputs a normal status indicates that the equipment is operating normally and there is no potential risk.

[0065] This invention provides a real-time online monitoring and fault diagnosis system for reactor rod level detectors, including...

[0066] Voltage and current sensors are used to collect the voltage and current signals of the primary coil and the auxiliary coil of the rod position detector, respectively. A voltage sensor is installed on the measuring device of the rod position detector to collect the voltage signals of the five sets of measuring coils.

[0067] The data filtering module performs data filtering processing on the primary coil voltage signal, primary coil current signal, auxiliary coil voltage signal, and 5 sets of measurement coil voltage signals of each rod position detector.

[0068] The data preprocessing module extracts the primary coil resistance, inductance, amplitude, frequency, phase, and other characteristic parameters of each rod position detector.

[0069] The threshold comparison module performs threshold comparisons on the characteristic parameters of a single rod-position detector.

[0070] Early warning and alarm module.

[0071] 1. A real-time online monitoring and fault diagnosis technology for reactor rod level detectors, characterized by comprising the following steps:

[0072] ① Voltage sensors and current sensors are respectively arranged in the power supply and measurement circuits of the rod position detector to complete the acquisition of primary coil current, primary coil voltage, auxiliary coil voltage, and A / B / C / D / E code coil voltage data of each rod position detector.

[0073] ② The collected status data is preprocessed, and the primary coil resistance, inductance, amplitude, frequency, phase and other characteristic parameters of each rod position detector are extracted from it.

[0074] ③ Perform threshold comparison on the characteristic parameters of a single rod-position detector. When the value exceeds the warning value, output the warning information; when the value exceeds the alarm value, output the alarm information.

[0075] ④ The characteristic parameters of the 69 rod position detectors are grouped according to the core layout. The same characteristic parameter in each group is compared, and the 3σ principle is used to detect abnormal values ​​and output early warning signals.

[0076] ⑤ Based on the status monitoring and fault diagnosis results of the rod position detectors in S4 and S5, output the final status of each rod position detector. If a rod position detector has neither warning information nor alarm information, output the normal status.

[0077] 2. As described in claim 1, the primary coil current and voltage signals are collected in the power supply circuit of the rod position detector, and key characteristic parameters such as the resistance and inductance of the primary coil are extracted accordingly. All methods of extracting resistance and inductance parameters by arranging relevant signal sensors are within the scope of this patent's claims.

[0078] 3. As described in claim 1, the voltage signals of the primary coil, auxiliary coil, and A / B / C / D / E code coils are collected in the power supply and measurement circuit of the rod position detector, and characteristic parameter information such as amplitude, frequency, and phase of each coil is extracted based on these signals. All methods of extracting parameters such as amplitude, frequency, and phase by arranging relevant signal sensors are within the scope of the claims of this patent.

[0079] 4. All algorithms for identifying faults in rod position detectors using threshold comparison of key feature parameters as described in claim 1 are within the scope of the claims of this patent.

[0080] 5. All algorithms that utilize core arrangement to group rod position detectors and compare the changing trends of the same key characteristic parameter in each group to predict the performance of rod position detectors, as described in claim 1, are within the scope of the claims of this patent.

[0081] 6. The algorithm for extracting the resistance and inductance of the primary coil of the rod position detector by impedance calculation as described in claim 2 is within the scope of the claims of this patent.

[0082] 7. The algorithm described in claim 3, which uses Hilbert transformation and Parker transformation to extract characteristic parameters such as amplitude, frequency, and phase of each coil of the rod-position detector, is within the scope of the claims of this patent.

[0083] 8. The method for detecting abnormal values ​​of rod position detectors within the same group using the 3σ principle as described in claim 5 is within the scope of the claims of this patent.

[0084] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0085] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for real-time online monitoring and fault diagnosis of reactor rod level detectors, characterized in that, Specifically, the steps include the following: S1. Collect the voltage and current signals of the primary coil of the rod position detector, the voltage signal of the auxiliary coil, and the voltage signal of the measuring coil, respectively. S2. Perform data filtering processing on the primary coil voltage signal, primary coil current signal, auxiliary coil voltage signal, and measurement coil voltage signal of each rod position detector collected by the signal sensor in step S1. S3. Perform data preprocessing on the filtered data from step S2 to extract the primary coil resistance, inductance, amplitude, frequency, and phase characteristic parameters of each rod position detector. S4. Perform threshold comparison on the characteristic parameters of the single rod position detector processed in step S3. When the value exceeds the warning value, output the warning information; when the value exceeds the alarm value, output the alarm information. S5. Group all the characteristic parameters of the rod detectors processed in step S3 according to the core arrangement, compare the same characteristic parameter in each group, and use the 3σ principle to detect outliers. S6, combining the status monitoring and fault diagnosis results of the rod position detectors in S4 and S5, outputs the final status of each rod position detector.

2. The method for real-time online monitoring and fault diagnosis of reactor rod level detectors according to claim 1, characterized in that, In step S1, voltage and current sensors are installed on the power supply device of each rod position detector to collect the voltage and current signals of the primary coil and the voltage signal of the auxiliary coil of the rod position detector, respectively; a voltage sensor is installed on the measuring device of the rod position detector to collect the voltage signal of the measuring coil, respectively.

3. The method for real-time online monitoring and fault diagnosis of reactor rod level detectors according to claim 1, characterized in that, The method for extracting the resistance and inductance of the primary coil in the data preprocessing is as follows: The measured voltage and current of the primary coil are V, respectively. 原边 and I 原边 The impedance of the coil is calculated as follows: Impedance value Z 原边 It should be a complex number, and the resistance and inductance information of the coil should be obtained according to the following formula: Z 原边 =R 原边 +j(2πfL 原边 ) In the above calculation results, R 原边 This refers to the resistance information of the primary coil, L. 原边 This refers to the inductance information of the primary coil; where j is the imaginary unit and f is the power supply frequency.

4. The method for real-time online monitoring and fault diagnosis of reactor rod level detectors according to claim 1, characterized in that, The method for extracting the amplitude, frequency, and phase information of all coils in the data preprocessing is as follows: The collected coil voltage signals are labeled as V. in and V in As signal V α The signal V is obtained using the Hilbert transform. β V obtained by Hilbert transform α and V β By using the Parker transform and average filtering, the signal V is obtained. d V q Then, the measured values ​​V of the signal amplitude, initial phase, and frequency are obtained. And f1, integrating over 2πf1, we get θ1; finally, Adding θ1 to θ2 yields the measured value of the input signal phase.

5. The method for real-time online monitoring and fault diagnosis of reactor rod level detectors according to claim 1, characterized in that, The process for outlier detection based on the 3σ principle is as follows: S501. Calculate the mean and standard deviation of the data series to be tested; S502. Compare whether the deviation of each value in the data column from the average value exceeds 3 times σ. If it exceeds 3 times σ, output a warning signal.

6. The method for real-time online monitoring and fault diagnosis of reactor rod level detectors according to claim 1, characterized in that, In step S6, if a certain rod position detector has neither a warning message nor an alarm message, it outputs a normal state.

7. The method for real-time online monitoring and fault diagnosis of reactor rod level detectors according to claim 6, characterized in that, A rod position detector that outputs an alarm status indicates that the equipment has malfunctioned and needs to be replaced or repaired; a rod position detector that outputs a warning status indicates that the equipment can still operate, but there may be a risk of failure, requiring close monitoring or early replacement or repair. A rod position detector that outputs a normal status indicates that the device is operating normally and there is no potential risk.

8. A real-time online monitoring and fault diagnosis system for reactor rod level detectors, characterized in that, It includes a voltage sensor and a current sensor, which respectively collect the voltage signal and current signal of the primary coil of the rod position detector, as well as the voltage signal of the auxiliary coil; a voltage sensor is set on the measuring device of the rod position detector to collect the voltage signals of 5 sets of measuring coils respectively; The data filtering module performs data filtering processing on the primary coil voltage signal, primary coil current signal, auxiliary coil voltage signal, and 5 sets of measurement coil voltage signals of each rod position detector. The data preprocessing module extracts the resistance and inductance of the primary coil of each rod position detector, as well as the amplitude, frequency, and phase characteristic parameters of all coils. The threshold comparison module performs threshold comparisons on the characteristic parameters of a single rod-position detector. Early warning and alarm module.

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