Steam turbine rotor axial rubbing identification method and system based on state parameter analysis

Abstract

The present disclosure proposes a method and system for identifying axial rub of a steam turbine rotor based on state parameter analysis, the method comprising: obtaining radial shaft vibration data during the operation of the steam turbine to determine whether a shaft vibration jump occurs and whether a trend after the shaft vibration jump meets a condition; if so, obtaining axial displacement data and then obtaining a relative change rate of the axial displacement, and determining whether the steam turbine is equipped with a rotating machinery diagnostic monitoring and management system; if so, obtaining a target frequency less than a set frequency and a ratio of the target frequency to the amplitude change of the passband frequency based on the radial shaft vibration data, and performing axial rub identification based on the ratio and the relative change rate of the axial displacement; if not, obtaining active power data and a characteristic flow area, obtaining an active power relative change rate and an area deviation rate based on the active power data and the characteristic flow area, and performing axial rub identification based on the relative change rate of the axial displacement, the relative change rate of the active power and the area deviation rate.

Description

Technical Field

[0001] The present disclosure relates to the field of power machinery engineering, and in particular to a method and system for identifying axial rubbing of a steam turbine rotor based on state parameter analysis. Background Art

[0002] Vibration is a key indicator of the safe operation of steam turbine generator sets. There are many types of vibration failures and their inducing factors. Among them, dynamic-static rubbing is currently the most common and most common type of vibration failure. Rubbing is essentially a dry friction phenomenon caused by the disappearance of the static-dynamic clearance between rotating and stationary components. This produces force and thermal shock effects, causing the unit's vibration to deteriorate. Based on the direction of the rubbing force, dynamic-static rubbing can be divided into radial rubbing and axial rubbing. Axial rubbing generally causes significantly more damage and destruction to equipment than radial rubbing.

[0003] During actual unit operation, factors such as improper maintenance and installation, blade fouling, component damage, and thrust bearing failure can cause abnormal changes in axial thrust, destroying the original axial clearance and, in severe cases, causing axial rubbing. Conventional radial rubbing identification methods have benefited from the development of radial bearing vibration monitoring and diagnosis technology and are relatively complete. However, axial rubbing is currently difficult to identify due to the limited number of rotor axial measurement points and a small number of monitoring parameters. In addition, due to the weak axial constraint boundary conditions and low damping of the turbine rotor, once axial rubbing excitation force exists, it is easy to cause extreme axial vibration. When axial rubbing is severe, it will cause irreversible damage to the turbine flow section. Against this background, the accurate identification and diagnosis of axial rubbing is particularly urgent and important. Summary of the Invention

[0004] The present disclosure provides a method and system for identifying axial rub of a steam turbine rotor based on state parameter analysis, the main purpose of which is to be able to timely and accurately identify axial rub faults of a steam turbine rotor.

[0005] According to a first embodiment of the present disclosure, a method for identifying axial rubbing of a steam turbine rotor based on state parameter analysis is provided, comprising:

[0006] Acquire radial shaft vibration data of each measuring point of the shaft system during a preset time period during the operation of the steam turbine, obtain jump amplitudes of multiple measuring points based on the radial shaft vibration data, and then determine whether a shaft vibration jump occurs; if a shaft vibration jump occurs, analyze the trend of the radial shaft vibration data after the jump to determine whether the trend after the shaft vibration jump meets a condition;

[0007] If the conditions are met, the axial displacement data of the steam turbine during operation is obtained, the relative rate of change of the axial displacement is obtained based on the axial displacement data, and it is determined whether the steam turbine is equipped with a rotating machinery diagnostic monitoring and management system;

[0008] If yes, a target frequency less than a set frequency and a ratio of the target frequency to the amplitude change of the pass frequency are obtained according to the radial shaft vibration data, and axial rubbing is identified based on the ratio and the relative change rate of the axial displacement;

[0009] Otherwise, active power data and characteristic flow area are obtained, and the relative change rate of active power and the area deviation rate are obtained according to the active power data and the characteristic flow area, and axial friction identification is performed based on the relative change rate of axial displacement, the relative change rate of active power and the area deviation rate.

[0010] In one embodiment of the present disclosure, the jump amplitudes of multiple measuring points are obtained based on the radial shaft vibration data, and then whether a shaft vibration jump occurs is determined. If a shaft vibration jump occurs, the trend of the radial shaft vibration data after the jump is analyzed to determine whether the trend after the shaft vibration jump meets a condition, including: obtaining the jump amplitudes of multiple measuring points based on the radial shaft vibration data, and determining whether the jump amplitudes of the target measuring point with the largest jump amplitude and the adjacent measuring points of the target measuring point are respectively greater than or equal to the corresponding amplitude thresholds. If so, a shaft vibration jump occurs; analyzing the trend of the radial shaft vibration data after the jump to determine whether the target measuring point falls back within a first set time. If so, the trend after the shaft vibration jump meets the condition.

[0011] In one embodiment of the present disclosure, the obtaining of axial displacement data during the operation of the steam turbine and obtaining the relative change rate of the axial displacement based on the axial displacement data include: obtaining the axial displacement data during the operation of the steam turbine, performing trend analysis on the axial displacement data, and determining whether the axial displacement jumps within a second set time before the shaft vibration jump occurs, and if so, obtaining the relative change rate of the axial displacement.

[0012] In one embodiment of the present disclosure, obtaining a target frequency less than a set frequency and a ratio of the target frequency to the amplitude change of the passband based on the radial shaft vibration data includes: using the rotating machinery diagnostic monitoring and management system to perform spectral analysis on the radial shaft vibration data to determine whether there is a target frequency less than the set frequency, and if so, calculating the ratio of the amplitude change of the target frequency to the amplitude change of the passband.

[0013] In one embodiment of the present disclosure, the axial rubbing identification based on the ratio and the relative change rate of the axial displacement includes: judging whether the ratio is greater than or equal to a proportion threshold; if it is greater than or equal to the proportion threshold, judging whether the relative change rate of the axial displacement is greater than or equal to a first change rate threshold; if it is greater than or equal to the first change rate threshold, axial rubbing occurs in the turbine rotor.

[0014] In one embodiment of the present disclosure, the active power data and the characteristic flow area are obtained, and the active power relative change rate and the area deviation rate are obtained based on the active power data and the characteristic flow area, including: obtaining the active power data during the operation of the steam turbine, performing trend analysis on the active power data, and judging whether the active power jumps within the second set time before the shaft vibration jump occurs, and if so, obtaining the active power relative change rate; determining the bearing with the largest jump amplitude in the shaft vibration jump, obtaining the steam flow of the cylinder supported by the bearing, the steam temperature and steam pressure at the steam inlet position, and the steam pressure at the steam extraction port position, calculating the first characteristic flow area and the second characteristic flow area under the same active power before and after the shaft vibration jump, and obtaining the area deviation rate based on the first characteristic flow area and the second characteristic flow area.

[0015] In one embodiment of the present disclosure, the axial rub identification based on the relative change rate of the axial displacement, the relative change rate of the active power and the area deviation rate includes: judging whether the relative change rate of the axial displacement is greater than or equal to a first change rate threshold; if it is greater than or equal to the first change rate threshold, then judging whether the relative change rate of the active power is greater than or equal to a second change rate threshold, and whether the area deviation rate is greater than or equal to the deviation rate threshold; if the relative change rate of the active power is greater than or equal to the second change rate threshold and / or the area deviation rate is greater than or equal to the deviation rate threshold, axial rub occurs in the turbine rotor.

[0016] According to a second aspect of the present disclosure, a steam turbine rotor axial rubbing identification system based on state parameter analysis is also provided, comprising:

[0017] A shaft vibration processing module is used to obtain radial shaft vibration data of each measuring point of the shaft system during a preset time period during the operation of the steam turbine, obtain the jump amplitude of multiple measuring points based on the radial shaft vibration data, and then determine whether a shaft vibration jump occurs. If a shaft vibration jump occurs, analyze the trend of the radial shaft vibration data after the jump to determine whether the trend after the shaft vibration jump meets the conditions, and output a satisfaction signal if the conditions are met;

[0018] a displacement processing module, configured to, after receiving the satisfaction signal, obtain axial displacement data during the operation of the steam turbine, and obtain a relative change rate of the axial displacement according to the axial displacement data;

[0019] A judgment module is used to judge whether the steam turbine is equipped with a rotating machinery diagnosis, monitoring and management system, and outputs an equipped signal if the steam turbine is equipped with a rotating machinery diagnosis, monitoring and management system, otherwise outputs a not equipped signal;

[0020] a first comprehensive processing module configured to, after receiving the equipped signal, obtain a target frequency less than a set frequency and a ratio of the target frequency to the amplitude change of the pass frequency according to the radial shaft vibration data, and perform axial rubbing identification based on the ratio and the relative change rate of the axial displacement;

[0021] The second comprehensive processing module is used to obtain active power data and characteristic flow area after receiving the unequipped signal, obtain the active power relative change rate and area deviation rate according to the active power data and the characteristic flow area, and perform axial friction identification based on the axial displacement relative change rate, the active power relative change rate and the area deviation rate.

[0022] In one embodiment of the present disclosure, the shaft vibration processing module is specifically used to: obtain the jump amplitude of multiple measuring points based on the radial shaft vibration data, determine whether the jump amplitudes of the target measuring point with the largest jump amplitude and the adjacent measuring points of the target measuring point are respectively greater than or equal to the corresponding amplitude thresholds, and if so, a shaft vibration jump occurs; analyze the trend of the radial shaft vibration data after the jump, and determine whether the target measuring point falls back within a first set time, and if so, the trend after the shaft vibration jump meets the conditions.

[0023] In one embodiment of the present disclosure, the displacement processing module is specifically used to: obtain axial displacement data during the operation of the turbine, perform trend analysis on the axial displacement data, determine whether the axial displacement jumps within a second set time before the shaft vibration jump occurs, and if so, obtain the relative change rate of the axial displacement.

[0024] In one embodiment of the present disclosure, the first comprehensive processing module includes: a ratio processing unit, which is used to use the rotating machinery diagnostic monitoring and management system to perform spectral analysis on the radial shaft vibration data to determine whether there is a target frequency less than the set frequency, and if so, calculate the ratio of the amplitude change of the target frequency to the amplitude change of the pass frequency.

[0025] In one embodiment of the present disclosure, the first comprehensive processing module is specifically used to: determine whether the ratio is greater than or equal to a proportion threshold; if it is greater than or equal to the proportion threshold, determine whether the relative change rate of the axial displacement is greater than or equal to a first change rate threshold; if it is greater than or equal to the first change rate threshold, axial friction occurs in the turbine rotor.

[0026] In one embodiment of the present disclosure, the second comprehensive processing module includes: a power processing unit, which is used to obtain active power data during the operation of the steam turbine, perform trend analysis on the active power data, and determine whether the active power jumps within the second set time before the shaft vibration jump occurs. If so, the relative change rate of the active power is obtained; an area processing unit, which is used to determine the bearing with the largest jump amplitude in the shaft vibration jump, obtain the steam flow of the cylinder supported by the bearing, the steam temperature and steam pressure at the steam inlet position, and the steam pressure at the steam extraction port position, calculate the first characteristic flow area and the second characteristic flow area under the same active power before and after the shaft vibration jump, and obtain the area deviation rate based on the first characteristic flow area and the second characteristic flow area.

[0027] In one embodiment of the present disclosure, the second comprehensive processing module is specifically used to: determine whether the relative change rate of the axial displacement is greater than or equal to a first change rate threshold; if it is greater than or equal to the first change rate threshold, then determine whether the relative change rate of the active power is greater than or equal to a second change rate threshold, and whether the area deviation rate is greater than or equal to the deviation rate threshold; if the relative change rate of the active power is greater than or equal to the second change rate threshold and / or the area deviation rate is greater than or equal to the deviation rate threshold, axial friction occurs in the turbine rotor.

[0028] According to an embodiment of the third aspect of the present disclosure, an electronic device is also provided, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the turbine rotor axial friction identification method based on state parameter analysis proposed in the embodiment of the first aspect of the present disclosure.

[0029] According to the fourth aspect embodiment of the present disclosure, a non-transitory computer-readable storage medium storing computer instructions is also provided, wherein the computer instructions are used to enable the computer to execute the turbine rotor axial friction identification method based on state parameter analysis proposed in the first aspect embodiment of the present disclosure.

[0030] According to the fifth embodiment of the present disclosure, a computer program product is also provided, including a computer program, which, when executed by a processor, implements the turbine rotor axial rubbing identification method based on state parameter analysis proposed in the first embodiment of the present disclosure.

[0031] In one or more embodiments of the present disclosure, radial shaft vibration data is obtained during the operation of the turbine, and based on the radial shaft vibration data, it is determined whether a shaft vibration jump occurs and whether the trend after the shaft vibration jump meets the conditions. If the conditions are met, the axial displacement data is obtained, and then the relative change rate of the axial displacement is obtained, and it is determined whether the turbine is equipped with a rotating machinery diagnostic monitoring and management system; if equipped, the axial rubbing is identified based on the ratio of the amplitude change of the target frequency to the pass frequency and the relative change rate of the axial displacement in combination with the target frequency that is less than the set frequency in the radial shaft vibration data; if not equipped, the axial rubbing is identified based on the relative change rate of the axial displacement, the relative change rate of the active power and the area deviation rate in combination with the active power data and the characteristic flow area. In this case, by collecting the radial vibration, axial displacement, active power, steam flow, steam pressure, steam temperature and other state parameters of the turbine under operation and performing feature analysis, the axial rubbing fault of the turbine rotor can be identified in a timely and accurate manner.

[0032] Additional aspects and advantages of the present disclosure will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and / or additional aspects and advantages of the present disclosure will become apparent and readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0034] Figure 1 A schematic flow chart of a first method for identifying axial rubbing of a steam turbine rotor based on state parameter analysis provided by an embodiment of the present disclosure is shown;

[0035] Figure 2 A schematic flow chart of a second method for identifying axial rubbing of a steam turbine rotor based on state parameter analysis provided by an embodiment of the present disclosure is shown;

[0036] Figure 3 It shows the spectrum diagram of the moment when the turbine rotor experiences abnormal vibration jump;

[0037] Figure 4 A schematic diagram showing the wear of the thrust bearing pads after axial friction occurs on the high-pressure rotor;

[0038] Figure 5 A trend chart showing abnormal vibration jumps;

[0039] Figure 6 A schematic diagram showing the wear of the first three stages of the high-pressure rotor after axial friction occurs;

[0040] Figure 7 A structural block diagram of a first steam turbine rotor axial rubbing identification system based on state parameter analysis provided by an embodiment of the present disclosure is shown;

[0041] Figure 8 A structural block diagram of a second steam turbine rotor axial rubbing identification system based on state parameter analysis provided by an embodiment of the present disclosure is shown;

[0042] Figure 9 It is a block diagram of an electronic device used to implement the steam turbine rotor axial rub identification method based on state parameter analysis according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0043] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all possible implementations consistent with the present disclosure. Rather, they are merely examples of apparatuses and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

[0044] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and features of different embodiments or examples, unless they are mutually inconsistent.

[0045] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present disclosure, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. It should also be understood that the term "and / or" used in the present disclosure refers to and includes any or all possible combinations of one or more associated listed items.

[0046] The following describes in detail embodiments of the present disclosure, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present disclosure, and should not be construed as limiting the present disclosure.

[0047] In the first embodiment, if Figure 1 As shown, Figure 1 A schematic flow chart of a first method for identifying axial rub of a steam turbine rotor based on state parameter analysis, provided by an embodiment of the present disclosure, is shown. The method for identifying axial rub of a steam turbine rotor based on state parameter analysis in the present disclosure may be referred to as a steam turbine rotor axial rub identification method or identification method. Specifically, the method for identifying axial rub of a steam turbine rotor based on state parameter analysis includes:

[0048] S101, obtaining radial shaft vibration data of each measuring point of the shaft system in a preset time period during the operation of the steam turbine, obtaining the jump amplitude of multiple measuring points based on the radial shaft vibration data, and then determining whether a shaft vibration jump occurs; if a shaft vibration jump occurs, analyzing the trend of the radial shaft vibration data after the jump to determine whether the trend after the shaft vibration jump meets the conditions.

[0049] It is easy to understand that the shaft vibration data is a vibration signal, which is a periodic signal with the rotational speed as the fundamental frequency. The radial shaft vibration data is the vibration signal of the rotor in the radial direction.

[0050] In some embodiments, the preset time period can be set as required. The radial shaft vibration data can be obtained by collecting vibration signals at each measuring point of the shaft system through a sensor, wherein the position of the measuring point can be the position of the measuring point currently detecting the shaft vibration.

[0051] In this embodiment, the number of measuring points in step S101 is at least 2, and at least one group of measuring points is adjacent to each other. In other embodiments, the number of measuring points can be adjusted according to needs.

[0052] In some embodiments, step S101 obtains radial shaft vibration data of each measuring point of the shaft system in a preset time period during the operation of the steam turbine, obtains the jump amplitude of multiple measuring points based on the radial shaft vibration data, and then determines whether a shaft vibration jump occurs. If a shaft vibration jump occurs, the trend of the radial shaft vibration data after the jump is analyzed to determine whether the trend after the shaft vibration jump meets the conditions, including: obtaining radial shaft vibration data of each measuring point of the shaft system in a preset time period during the operation of the steam turbine, obtaining the jump amplitude of multiple measuring points based on the radial shaft vibration data, and determining whether the jump amplitudes of the target measuring point with the largest jump amplitude and the adjacent measuring points of the target measuring point are respectively greater than or equal to the corresponding amplitude thresholds. If so, a shaft vibration jump occurs; analyzing the trend of the radial shaft vibration data after the jump to determine whether the target measuring point falls back within the first set time. If so, the trend after the shaft vibration jump meets the conditions.

[0053] In this embodiment, the jump amplitude of the measuring point in step S101 is the absolute value of the difference between the maximum vibration value of the vibration signal during the first time period and the vibration value before the change. The vibration value can be a composite value or a peak-to-peak value. It is easy to understand that the composite value is the amplitude of the vibration values ​​of the measuring point in different directions within the same plane. The peak-to-peak value refers to the difference between the highest and lowest values ​​of the signal within a period.

[0054] In this embodiment, the value of the first time period can be selected from 0-3s. The first time period can be, for example, 0s, 1s, 2s, or 3s. The first time period is derived from a large amount of field experience data. In this case, for the vibration response under the force impact of dynamic and static friction, the vibration change time usually occurs instantaneously, within 3s. By shortening the threshold for the jump time, faults that may be dynamic and static friction can be more effectively screened out during the vibration trend analysis, thereby improving diagnostic efficiency.

[0055] Taking the first time period of 3 seconds as an example, in step S101, the measuring point with the largest jump amplitude is selected as the target measuring point. This target measuring point can be denoted as X1. A(t1) represents the vibration value of the target measuring point before the change, corresponding to time t1 (i.e., the time of the shaft vibration jump). A(t2) represents the maximum vibration value of the target measuring point during the first time period, corresponding to time t2. The jump amplitude of the target measuring point X1 is |A(t2)-A(t1)|, where t2-t1≤3s. |ΔA| represents the jump amplitude of the adjacent measuring points of the target measuring point X1. Each measuring point has a corresponding amplitude threshold. The corresponding amplitude threshold of the target measuring point X1 can be represented by C0. For example, when the vibration value is a composite value, C0 = 20 μm, and when the vibration value is peak-to-peak, C0 = 28 μm. The corresponding amplitude threshold of the adjacent measuring points of the target measuring point X1 can be represented by C1. For example, when the vibration value is a composite value, C1 = 5 μm, and when the vibration value is peak-to-peak, C1 = 7 μm. In addition, the amplitude threshold corresponding to the measurement point is not limited to the value in the example.

[0056] In step S101, if |A(t2)-A(t1)|≥C0, and at least one of the adjacent measuring points of the target measuring point X1 (for example, adjacent shaft vibration measuring points) also jumps at the same time, and the jump amplitude |ΔA|≥C1, it is considered that the radial vibration of the shaft system jumps (i.e., shaft vibration jump occurs).

[0057] In this embodiment, the time accuracy of the simultaneous transition of the target measuring point X1 and the adjacent measuring points of the target measuring point X1 may be 1 s, but the examples disclosed herein are not limited thereto.

[0058] In addition, in the embodiments of the present disclosure, the first time period can be obtained based on demand, actual conditions, or by summarizing a large amount of field experience data.

[0059] In this embodiment, if shaft vibration jump occurs, that is, the jump amplitudes of the target measurement point with the largest jump amplitude and the adjacent measurement points of the target measurement point are respectively greater than or equal to the corresponding amplitude thresholds, analyze the trend of the radial shaft vibration data after the jump to determine whether the target measurement point drops back within the first set time. If so, the trend of the shaft vibration after the jump meets the conditions.

[0060] Specifically, analyzing the trend of the radial shaft vibration data after the jump to determine whether the target measurement point drops back within the first set time includes: performing trend analysis on the vibration data after the shaft vibration jump, obtaining the vibration values at any two moments within the first set time after the target measurement point X1 reaches the maximum vibration value within the first time period, calculating the differences between the pre-change vibration value of the target measurement point and the vibration values at these two moments respectively. If the difference between the pre-change vibration value of the target measurement point and the vibration value at the later moment is less than the difference between the pre-change vibration value of the target measurement point and the vibration value at the earlier moment, then the target measurement point drops back within the first set time. The first set time can be, for example, 3s, but the examples of the present disclosure are not limited to this.

[0061] Taking the first set time as 3s as an example, based on the above, it can be known that the moment when the target measurement point X1 reaches the maximum vibration value A(t2) within the first time period is t2. Represent any two moments within 3s (the first set time) after the moment t2 by t3 and t4, where t2 ≤ t3 < t4 ≤ t2 + 3. The vibration values corresponding to the target measurement point X1 at the moments t3 and t4 are represented by A(t3) and A(t4). If A(t4) - A(t1) < A(t3) - A(t1), then the target measurement point drops back rapidly within the first set time. At this time, it can be preliminarily judged that the steam turbine rotor may have self-excited vibration, radial rubbing or axial rubbing. Otherwise, the steam turbine rotor has no axial rubbing. The first set time is 3s. In addition, by comprehensively considering the jump amplitudes of the target measurement point and its adjacent measurement points and the corresponding amplitude thresholds, as well as whether the target measurement point drops back rapidly, the force impact effect can be considered preferentially and fully. Therefore, the method of the present disclosure is more rapid and accurate for the identification of axial rubbing.

[0062] S102, if the conditions are met, obtain the axial displacement data during the operation of the steam turbine, obtain the relative change rate of the axial displacement according to the axial displacement data, and determine whether the steam turbine is equipped with a rotating machinery diagnosis and monitoring management system.

[0063] It is easy to understand that the axial displacement data is the amount of movement of the rotor along the axial direction.

[0064] In step S102, the axial displacement data during the operation of the steam turbine is obtained, and the relative change rate of the axial displacement is obtained based on the axial displacement data, including: obtaining the axial displacement data during the operation of the steam turbine, performing trend analysis on the axial displacement data, and determining whether the axial displacement jumps within a second set time before the shaft vibration jump occurs, and if so, obtaining the relative change rate of the axial displacement.

[0065] In this embodiment, in step S102, the axial displacement data obtained during the operation of the steam turbine is the axial displacement data within the second set time before (including the shaft vibration jump moment). The second set time is obtained by summarizing a large amount of field experience data, fully considering the close connection and logic of the occurrence time of abnormal axial displacement jump and axial friction, narrowing the data retrieval range, and at the same time reducing the amount of calculation and improving analysis efficiency. The value of the second set time can be selected from 1-5 minutes. For example, the second set time is 1 minute.

[0066] In step S102, it is determined whether the axial displacement jumps within the second set time before the occurrence of the shaft vibration jump. If so, obtaining the relative change rate of the axial displacement may include: if the axial displacement jumps within the second set time before the occurrence of the shaft vibration jump, obtaining the axial displacement values ​​of two moments within the set time interval in the second set time, and obtaining the relative change rate of the axial displacement based on the difference between the axial displacement values ​​of the two moments and the axial displacement value of the previous moment in the two moments. The set time interval may be, for example, 3s, but the examples disclosed herein are not limited thereto. The two moments may be t Ad1 and t Ad2 Indicates that t Ad1 <t Ad12 , the two moments satisfy t Ad2 -t Ad1 ≤3s, the axial displacement values ​​corresponding to the two moments can be expressed as Ad1 and Ad2. The relative rate of change of the axial displacement is |Ad2-Ad1| / |Ad1|.

[0067] In this embodiment, in step S102, it is determined whether the steam turbine is equipped with a rotating machinery diagnostic monitoring and management system (Turbine Diagnosis Management, TDM). If it is equipped with a TDM system, the process proceeds to step S102 for axial rub identification. If it is not equipped with a TDM system, the process proceeds to step S103 for axial rub identification.

[0068] S103: If yes, obtain a target frequency less than the set frequency and a ratio of the target frequency to the amplitude change of the pass frequency according to the radial shaft vibration data, and perform axial rubbing identification based on the ratio and the relative change rate of the axial displacement.

[0069] In some embodiments, the specific steps of obtaining a target frequency less than the set frequency and the ratio of the target frequency to the amplitude change of the passband according to the radial shaft vibration data in step S103 include: using a rotating machinery diagnostic monitoring and management system to perform spectral analysis on the radial shaft vibration data to determine whether there is a target frequency less than the set frequency, and if so, calculating the ratio of the amplitude change of the target frequency to the amplitude change of the passband.

[0070] Specifically, in step S103, the rotating machinery diagnostic monitoring and management system performs spectrum analysis on the radial shaft vibration data to determine whether there is a target frequency less than the set frequency. This includes: using a TDM system to perform Fourier transform and spectrum analysis on the radial shaft vibration data obtained in step S101, extracting characteristic data such as low-frequency components and single-harmonic components, and analyzing characteristic data when shaft vibration jumps occur to determine whether there is a target frequency less than the set frequency. The set frequency can be less than or equal to 3 Hz. For example, if the set frequency is 3 Hz, the target frequency is all frequencies less than 3 Hz.

[0071] In step S103, if there is a target frequency less than the set frequency, calculating the ratio of the target frequency amplitude change to the passband amplitude change includes: obtaining the maximum peak value and the passband amplitude of all frequencies of the target frequency at the moment of the shaft vibration jump, as well as the maximum peak value and the passband amplitude of all frequencies of the target frequency at the target moment, calculating the amplitude change of the maximum peak value of the target frequency and the amplitude change of the passband, and calculating the ratio of the amplitude change of the target frequency to the amplitude change of the passband. The target moment is the moment corresponding to the maximum vibration value of the target measuring point within the first time period.

[0072] Taking the set frequency as 3Hz as an example, obtain the maximum peak value of the target frequency less than 3Hz on the spectrum at the time of shaft vibration jump (t1), and use A f01 Indicates that the maximum peak value of the target frequency less than 3Hz on the target time (t2) is obtained, and A f02 To obtain the full-frequency amplitude at the moment of shaft vibration jump (t1), it can be expressed by the vibration value before the change of the target measuring point A(t1). To obtain the full-frequency amplitude at the target moment (t2), it can be expressed by the maximum vibration value of the target measuring point in the first time period A(t2). The amplitude change of the maximum peak value of the target frequency is |A f02 -A f01 |, the amplitude change of the passband is |A(t2)-A(t1)|, and the ratio of the amplitude change of the target frequency to the amplitude change of the passband is |A f02 -A f01 | / |A(t2)-A(t1)|.

[0073] In some embodiments, the specific steps of identifying axial rubbing based on the ratio and the relative change rate of axial displacement in step S103 include: determining whether the ratio is greater than or equal to the proportion threshold; if it is greater than or equal to the proportion threshold, determining whether the relative change rate of axial displacement is greater than or equal to the first change rate threshold; if it is greater than or equal to the first change rate threshold, axial rubbing occurs in the turbine rotor.

[0074] In step S103, it is determined whether the ratio of the amplitude change of the target frequency to the amplitude change of the pass frequency is greater than or equal to the ratio threshold. If it is, self-excited vibration is excluded and it can be determined that radial rubbing or axial rubbing may occur in the turbine rotor. Otherwise, no axial rubbing occurs. The ratio threshold value can be selected from 50% to 60%. Taking the ratio threshold as 50% as an example, that is, |A f02 -A f01 When | / |A(t2)-A(t1)|≥50%, it can be determined that radial or axial rubbing is likely occurring in the turbine rotor, eliminating self-excited vibration. In this case, since extensive field data indicates that the frequency of steam flow excitation and oil film instability faults during constant-speed operation of steam turbines ranges from 10 to 25 Hz, excluding extremely low frequencies less than 3 Hz, this disclosure limits the target frequency to extremely low-frequency components less than 3 Hz. This clearly specifies the frequency range of these low-frequency components, enabling accurate screening of dynamic and static rubbing faults, eliminating similar faults, and improving diagnostic efficiency.

[0075] In step S103, if the relative rate of change of the axial displacement is greater than or equal to the proportion threshold, a determination is made as to whether the relative rate of change of the axial displacement is greater than or equal to a first rate of change threshold. If so, axial rubbing occurs in the turbine rotor. The first rate of change threshold can be selected from a range of 50% to 60%. For example, when the first rate of change threshold is 50%, that is, when |Ad2-Ad1| / |Ad1| ≥ 50%, the axial displacement jump amplitude is considered to meet the conditions, radial rubbing is excluded, and axial rubbing is determined to occur in the turbine rotor. Otherwise, axial rubbing does not occur. In this case, refining the threshold value of the relative rate of change of the axial displacement for axial rubbing faults can be well suited for accurately screening axial rubbing faults. In addition, compared to the prior art determination method that directly compares the displacement amount with the corresponding threshold, the present disclosure utilizes more comprehensive data related to the relative rate of change of the axial displacement. Furthermore, the relative rate of change is used to determine the change in the axial displacement at different times, and its absolute change can be adaptively adjusted, resulting in more accurate determination results, a wider range of applications, and greater adaptability.

[0076] S104, if not, obtain active power data and characteristic flow area, obtain active power relative change rate and area deviation rate according to the active power data and characteristic flow area, and perform axial rubbing identification based on the axial displacement relative change rate, active power relative change rate and area deviation rate.

[0077] In some embodiments, active power data and characteristic flow area are obtained in step S104, and specific steps of obtaining the active power relative change rate and area deviation rate based on the active power data and characteristic flow area include: obtaining active power data during the operation of the steam turbine, performing trend analysis on the active power data, and judging whether the active power jumps within the second set time before the shaft vibration jump occurs, and if so, obtaining the active power relative change rate; determining the bearing with the largest jump amplitude in the shaft vibration jump, obtaining the steam flow rate of the cylinder supported by the bearing, the steam temperature and steam pressure at the steam inlet position, and the steam pressure at the steam extraction port position, calculating the first characteristic flow area and the second characteristic flow area under the same active power before and after the shaft vibration jump, and obtaining the area deviation rate based on the first characteristic flow area and the second characteristic flow area.

[0078] Specifically, the active power data during the operation of the steam turbine obtained in step S104 is the active power data within the second set time before (including the shaft vibration jump moment). The second set time is obtained by summarizing a large amount of field experience data, fully considering the close connection and logic between the abnormal jump of active power and axial friction in the occurrence time, narrowing the data retrieval range, and at the same time reducing the amount of calculation and improving analysis efficiency. The value of the second set time can be selected from 1-5 minutes. For example, the second set time is 1 minute.

[0079] In step S104, determining whether the active power jumps within the second set time before the shaft vibration jump occurs, and if so, obtaining the relative change rate of the active power may include: if the active power jumps within the second set time before the shaft vibration jump occurs, obtaining the active power values ​​of two moments within the set time interval in the second set time, and obtaining the relative change rate of the active power based on the difference between the active power values ​​of the two moments and the active power value of the previous moment between the two moments. The set time interval may be, for example, 3s, but the examples disclosed herein are not limited thereto. The two moments may be t W1 and t W2 Indicates that t W1 <t W2 , the two moments satisfy t W2 -t W1 ≤3s. The active power values ​​corresponding to these two moments can be represented by W1 and W2. The relative rate of change of active power is |W2-W1| / W1. In addition, the rated active power of the turbine can be represented by W0.

[0080] In this embodiment, the bearing with the largest jump amplitude among the shaft vibration jumps determined in step S104 is the bearing where the target measurement point X1 is located. The cylinder supported by this bearing can be denoted as cylinder A. Relevant operating parameter data such as the steam flow rate of cylinder A, the steam temperature and steam pressure at the steam inlet position, and the steam pressure at the extraction port position are obtained. Here, the steam temperature and steam pressure at the steam inlet position are represented by T1 and p1 respectively, and the steam pressure at the extraction port position can be represented by p2.

[0081] In this embodiment, calculating the first characteristic flow area and the second characteristic flow area at the same active power before and after the shaft vibration jump, and obtaining the area deviation rate based on the first characteristic flow area and the second characteristic flow area specifically includes:

[0082] Set the flow part between the steam inlet and the extraction port of the cylinder as a stage group; obtain the relevant operating parameter data after operating for a second time period at the set power after the shaft vibration jump, and calculate the first characteristic flow area; obtain the relevant operating parameter data after operating for a second time period at the set power before the shaft vibration jump, and calculate the second characteristic flow area. Obtain the area deviation amount based on the first characteristic flow area and the second characteristic flow area, and divide the area deviation amount by the first characteristic flow area to obtain the area deviation rate.

[0083] Among them, the set power is the active power that can operate safely and stably, and the set power is represented by W3, that is, W3 < W0. The second time period can be, for example, 30 min, but the examples of the present disclosure are not limited to this.

[0084] In this embodiment, the formula for calculating the characteristic flow area of the stage group derived from the Flügel formula satisfies: In the formula, G is the steam flow rate passing through the stage group (unit: t / h), p0 is the pressure before the stage group (unit: MPa), υ0 is the specific volume before the stage group (unit: m 3 / kg), π is the pressure ratio of the stage group, that is, the ratio of the pressure after the stage group to the pressure before the stage group. Among them, the pressure before the stage group is equal to the steam pressure at the steam inlet position, and the pressure after the stage group is equal to the steam pressure at the extraction port position. In other words, the pressure ratio of the stage group can be obtained based on the steam pressure p1 at the steam inlet position and the steam pressure p2 at the extraction port position. The pressure ratio of the stage group satisfies: π = p2 / p1. The specific volume υ0 before the stage group can be obtained from the steam temperature T1 and steam pressure p1 at the steam inlet position. The first characteristic flow area and the second characteristic flow area are calculated using this formula for the characteristic flow area of the stage group. The first characteristic flow area can be represented by F V1 and the second characteristic flow area can be represented by F V2 The area deviation rate is f V = |F V1 - F V2 | / F V1.

[0085] In some embodiments, the specific steps of performing axial rubbing identification based on the relative change rate of axial displacement, the relative change rate of active power and the area deviation rate in step S104 include: judging whether the relative change rate of axial displacement is greater than or equal to a first change rate threshold; if it is greater than or equal to the first change rate threshold, then judging whether the relative change rate of active power is greater than or equal to a second change rate threshold, and whether the area deviation rate is greater than or equal to the deviation rate threshold; if the relative change rate of active power is greater than or equal to the second change rate threshold and / or the area deviation rate is greater than or equal to the deviation rate threshold, axial rubbing occurs in the turbine rotor.

[0086] Specifically, the determination of whether the relative rate of change of the axial displacement is greater than or equal to the first rate of change threshold in step S104 can be made with reference to the relevant description of step S103 and will not be repeated here. At this point, combined with the fact that the target measuring point falls back within the first set time in the above steps, and that the relative rate of change of the axial displacement is greater than or equal to the first rate of change threshold, self-excited vibration and radial rubbing can be ruled out, and a preliminary determination is made that axial rubbing of the turbine rotor occurs.

[0087] In step S104, if it is greater than or equal to the first change rate threshold, it is determined whether the relative change rate of active power is greater than or equal to the second change rate threshold, and whether the area deviation rate is greater than or equal to the deviation rate threshold; if the relative change rate of active power is greater than or equal to the second change rate threshold and / or the area deviation rate is greater than or equal to the deviation rate threshold, then the turbine rotor has axial rubbing. In other words, if at least one of the following conditions is met: the relative change rate of active power is greater than or equal to the second change rate threshold, and the area deviation rate is greater than or equal to the deviation rate threshold, then the turbine rotor has axial rubbing. The second change rate threshold can be, for example, 4%, that is, when |W2-W1| / W1≥4%, it can be considered that the active power jump amplitude meets the conditions, and it can be determined that the turbine rotor has axial rubbing. The deviation rate threshold can be, for example, 8%, that is, f V When it is ≥8%, it is considered that the characteristic flow area change amplitude meets the conditions, and it can be determined that the turbine rotor has axial rubbing. If the active power jump amplitude does not meet the conditions and the active power jump amplitude does not meet the conditions, it is determined that the turbine rotor has not had axial rubbing, otherwise it is said that the turbine rotor has had axial rubbing. The second change rate threshold and the deviation rate threshold of the example disclosed in the present invention are not limited to this. Thus, the judgment conditions can be simplified and the diagnostic efficiency can be improved. In addition, the present disclosure uses the data involved in the relative change rate of active power and the characteristic flow area deviation rate more comprehensively, and the use of the relative change rate and the area deviation rate is based on the change of the corresponding state parameters for judgment, and can adaptively adjust the absolute change amount, so that the judgment result is more accurate, the application range is wider, and the adaptability is higher.

[0088] In this embodiment, in the above-mentioned method for identifying axial friction of a steam turbine rotor, the steps of obtaining the axial displacement data during the operation of the steam turbine and determining whether the steam turbine is equipped with a rotating machinery diagnostic monitoring and management system in step S102 can be performed simultaneously or sequentially. When the steps are performed sequentially, there is no particular restriction on the order of the two. For example, in some embodiments, it is possible to first determine whether the steam turbine is equipped with a rotating machinery diagnostic monitoring and management system (TDM) and then obtain the axial displacement data. For the specific process, please refer to Figure 2 , Figure 2 A flow chart of a second method for identifying axial rubbing of a steam turbine rotor based on state parameter analysis provided by an embodiment of the present disclosure is shown. Figure 2 As shown in FIG, the steam turbine rotor axial rubbing identification method based on state parameter analysis includes:

[0089] 1) Obtain radial shaft vibration data of each measuring point of the shaft system during the operation of the steam turbine over a period of time and perform trend analysis on the data. When at least two adjacent shaft vibration measuring points simultaneously experience jumps, the jump amplitude of each measuring point is greater than or equal to the corresponding amplitude threshold, and the vibration of the measuring point with the largest jump amplitude quickly drops after the jump, it is preliminarily determined that the steam turbine rotor may experience self-excited vibration, radial rubbing, or axial rubbing, and the process proceeds to step 2). Otherwise, it indicates that the steam turbine rotor does not experience axial rubbing.

[0090] 2) When the steam turbine unit is not equipped with a rotating machinery diagnostic monitoring and management system (TDM), go directly to step 3). When equipped with a TDM system, perform the following analysis: perform spectrum analysis on the radial shaft vibration data obtained in step 1). When an extremely low frequency component (target frequency) with a frequency less than 3 Hz (set frequency) appears on the spectrum at the moment of vibration jump, and the ratio of its amplitude change to the frequency change is greater than or equal to 50% (the ratio threshold), self-excited vibration is ruled out, and it is preliminarily determined that radial or axial rubbing may occur in the steam turbine rotor, and go to step 3). Otherwise, it indicates that axial rubbing does not occur in the steam turbine rotor.

[0091] 3) Acquire axial displacement data during turbine operation and perform trend analysis. If the axial displacement also jumps within 1 minute before (including) the shaft vibration jump, and the amplitude of change (i.e., the relative rate of change of the axial displacement) is greater than or equal to the corresponding threshold, if spectrum analysis has been performed previously in step 2), radial rubbing is ruled out, and it can be determined that the turbine rotor has axial rubbing. If spectrum analysis has not been performed previously in step 2), self-excited vibration and radial rubbing are ruled out, and it is preliminarily determined that the turbine rotor has axial rubbing, and the process proceeds to steps 4) and 5) simultaneously. Otherwise (i.e., the amplitude of change of the axial displacement is less than the corresponding threshold), it indicates that the turbine rotor has not had axial rubbing.

[0092] 4) Obtain the active power data of the steam turbine before and after the shaft vibration jump and perform trend analysis. Within 1 minute before the shaft vibration jump (including the shaft vibration jump moment), observe whether the active power jumps. If the active power also jumps, and the change amplitude (i.e., the relative change rate of active power) is greater than or equal to the corresponding threshold (4%), it can be determined that the steam turbine rotor has axial friction. Otherwise, go to step 6);

[0093] 5) Obtain the bearing with the largest shaft vibration jump amplitude from step 1), obtain thermodynamic state parameters such as the steam flow rate of the cylinder supported by the bearing, the steam temperature and steam pressure at the steam inlet, and the steam pressure at the steam extraction port, and calculate thermodynamic state parameters such as the pressure ratio of the stage group (the flow passage from the steam inlet to the steam extraction port is defined as the stage group), the specific volume before the stage group, and then perform a stage group characteristic flow area analysis and calculate the characteristic flow area of ​​the stage group under the same active power before and after the shaft vibration jump, thereby obtaining the relative change rate of the characteristic flow area (i.e., the area deviation rate). When the area deviation rate is greater than or equal to the corresponding threshold (8%), it can be determined that axial rubbing of the turbine rotor occurs. Otherwise, go to step 6);

[0094] 6) When the active power change in step 4) and the characteristic flow area change of the intermediate group in step 5) do not meet the conditions (i.e., both are less than the corresponding thresholds), it is determined that the turbine rotor does not have axial rubbing; otherwise, it is indicated that the turbine rotor has axial rubbing.

[0095] in Figure 2 The detailed description of each step in the steam turbine rotor axial rubbing identification method based on state parameter analysis can be found in Figure 1 The description of the relevant processes in the steam turbine rotor axial rubbing identification method based on state parameter analysis shown in FIG. 1 will not be repeated here.

[0096] In the steam turbine rotor axial rub identification method based on state parameter analysis in the embodiment of the present disclosure, radial shaft vibration data during the operation of the steam turbine is obtained, and based on the radial shaft vibration data, whether a shaft vibration jump occurs and whether the trend after the shaft vibration jump meets the conditions are determined. If the conditions are met, axial displacement data is obtained, and then the relative change rate of axial displacement is obtained, and it is determined whether the steam turbine is equipped with a rotating machinery diagnostic monitoring and management system; if equipped, axial rub is identified based on the ratio of the amplitude change of the target frequency to the passband frequency and the relative change rate of axial displacement in combination with the target frequency in the radial shaft vibration data that is less than the set frequency; if not equipped, axial rub is identified based on the relative change rate of axial displacement, the relative change rate of active power and the area deviation rate in combination with the active power data and the characteristic flow area. In this case, by collecting and analyzing the turbine's operating parameters, such as radial vibration, axial displacement, active power, steam flow, steam pressure, and steam temperature, and performing characteristic analysis, it is possible to promptly and accurately identify turbine rotor axial rubbing faults. This also provides a scientific basis for operators and maintenance personnel to take appropriate countermeasures in advance, thereby promptly preventing damage to the flow passages within the cylinder and the thrust bearings. This approach offers high accuracy and real-time performance. Furthermore, the present disclosure directly utilizes data from the DCS and TDM systems that ship with the turbine generator set, eliminating the need for external instrumentation. This approach simplifies operation, facilitates on-site implementation, and provides reliable analysis results. This has been used repeatedly in field practice to accurately diagnose turbine rotor axial rubbing faults, ensuring equipment safety while also creating significant economic and social benefits for power plants.

[0097] The steam turbine rotor axial rub identification method based on state parameter analysis disclosed in this disclosure was used to identify vibration problems in steam turbine generator sets at multiple power plants. The identification results are as follows:

[0098] In response to the vibration problem of the No. 2 steam turbine generator unit of Power Plant A, the method disclosed in the present invention was used to successfully identify the axial friction fault. After the unit was shut down for inspection, it was found that obvious signs of collision and wear occurred at the thrust bearing pad position.

[0099] In response to the vibration problem of the No. 5 steam turbine generator unit in Power Plant B, the method disclosed in the present invention was applied to successfully identify the axial friction fault. After the unit was shut down and the cylinder was opened for inspection, it was found that the inside of the high-pressure cylinder was seriously damaged, and the first three stages of the high-pressure rotor's moving blade shrouds were in axial contact with the root of the lower-stage partition and suffered a severe axial friction fault. Among them, the second-stage moving blade top shrouds were seriously damaged, and the first seven stages of moving blade top shrouds were all worn to varying degrees. The steam inlet and steam outlet edges of the second to sixth stages of the stator's stators were all worn to varying degrees.

[0100] In response to the vibration problem of the No. 1 steam turbine generator unit in Power Plant C, the method disclosed in the present invention was used to successfully identify the axial friction fault. After the unit was shut down, the high-pressure cylinder was opened for inspection and it was found that the front shaft seal and the regulating stage were severely worn. Two grooves with a width of about 35 mm and a depth of about 13.5 mm were worn on the main shaft. The high teeth of the steam seal of the front steam seal section partition fell over, causing axial friction with the rotor boss.

[0101] In response to the vibration problem of Unit 4 of the D Power Plant, the method disclosed in the present invention was applied to successfully identify the axial friction fault. After the unit was shut down and the cylinder was opened for inspection, it was found that the entire circle of the medium-pressure second-stage partition guide vane had fallen off, including the steam seal piece, inner and outer rings, shaft seal block, etc. The entire circle of the second-stage moving blade was broken from the root, the second-stage wheel rim was severely damaged, and the steam outlet edge of the first-stage moving blade was severely damaged.

[0102] Taking the vibration problems of a 1000MW unit and a 660MW unit in a power plant as examples, the whole process of applying the present disclosure to diagnose axial rubbing faults is introduced in detail to illustrate the effectiveness and practicality of the identification method disclosed in the present disclosure.

[0103] (1) Case study of a 1000MW unit in a power plant

[0104] Table 1 lists the changes in relevant parameters before and after the abnormal vibration jump in the power plant. The data in Table 1 is from the power plant's distributed control system (DCS). It includes shaft vibration data from two measuring points and axial displacement data from one measuring point over a period of time. The vibration values ​​of the shaft vibration data are composite values. Measuring points 1 and 2 are adjacent measuring points. Table 1 shows that the target measuring point with the largest jump amplitude is measuring point 2. During the acquired period, at 13:53:48.594 (i.e., time t1), the vibration of shaft 2 suddenly increased from 65.6 μm to 132.7 μm within 0.2 seconds, a change of more than 20 μm. At 13:53:48.426, the vibration of the adjacent shaft 1 suddenly increased from 32.8 μm to 65.8 μm, a change of more than 5 μm. The jump times of shaft 2 and shaft 1 were within 1 second of each other, indicating that a jump in the shaft system's radial vibration occurred. And within 3 seconds after the jump, the vibration of shaft No. 2 dropped rapidly from 132.7μm to 92.3μm. Therefore, it was decided to start the axial rubbing diagnosis and identification program, and preliminarily judged that the turbine rotor may have self-excited vibration, radial rubbing or axial rubbing, and then proceeded to the next step of analysis.

[0105] Table 1 Shaft vibration value and axial displacement value before and after the jump

[0106]

[0107] The unit is equipped with a TDM system and enters the spectrum analysis program. Before the jump, the vibration of shaft 2 does not contain any extremely low frequency components less than 3Hz. Figure 3The spectrum of the turbine rotor vibration abnormal jump is shown. Figure 3 It can be seen that after the abnormal vibration jump, a large number of low-frequency components appeared, among which the peak value of the extremely low-frequency component was 1.25Hz, and the corresponding amplitude was 61.7μm (peak-to-peak value). Therefore, the amplitude change of the target frequency was 61.7μm, and the amplitude change of the passband before and after the abnormal jump was about 82.2μm (peak-to-peak value). The extremely low-frequency component of 1.25Hz accounted for 75% of the vibration change (i.e., the amplitude change). If it exceeds 50%, self-excited vibration is ruled out. It is preliminarily judged that radial friction or axial friction may occur in the turbine rotor, and the axial friction diagnosis and identification program is continued.

[0108] From the axial displacement change trend listed in Table 1 above, it can be seen that within 1 minute before the shaft vibration jump, the axial displacement 1 value was -0.037mm at 13:53:47.698 and -0.059mm at 13:53:48.426. The axial displacement 1 value changed by 0.022mm within 0.8s, and the relative change rate was 59.4%, which was greater than 50%, meeting the judgment conditions. Since the spectrum analysis has been performed in the previous step, radial friction is ruled out and it can be determined that the turbine rotor has axial friction.

[0109] Figure 4 The diagram shows the wear of the thrust bearing pad after the high-pressure rotor has axial collision friction. After the unit was shut down for inspection, it was found that the thrust bearing pad position of the high-pressure cylinder had obvious axial collision wear marks. The wear condition is shown in Figure 2. Figure 4 .

[0110] (2) Case study of a 660MW unit in a power plant

[0111] The unit, an N660-25 / 600 / 600 steam turbine manufactured by Shanghai Steam Turbine Works, was started up after maintenance on April 12. Table 2 lists the chronological series of events that occurred at the unit starting at 4:30 AM on April 13. The data in Table 2 is sourced from the power plant's DCS system. Figure 5 The black curve is the vibration trend of bearing No. 1, and the red curve is the vibration trend of bearing No. 2.

[0112] Table 2 Unit events before and after the jump

[0113]

[0114] from Figure 5 It can be seen from the trend curve of the abnormal vibration jump time that based on Table 2 and Figure 5At 4:31:07, shaft vibration No. 1 (i.e., bearing No. 1) suddenly increased from 24.6 μm to 50.7 μm within 2 seconds, a change exceeding 20 μm. At 4:31:07, the adjacent shaft vibration No. 2 (i.e., bearing No. 2) suddenly increased from 22.17 μm to 28.2 μm, a change exceeding 5 μm. The jump between shaft vibration No. 2 and shaft vibration No. 1 occurred within 1 second of each other, indicating a jump in the shaft system's radial vibration. Within 3 seconds after the jump, shaft vibration No. 1 rapidly decreased from 50.7 μm to 35 μm, and finally fell back to 21.2 μm at 4:31:14. Therefore, the axial rub diagnosis and identification program was initiated, and the preliminary diagnosis was that the turbine rotor might be experiencing self-excited vibration, radial rub, or axial rub, and the next step of analysis was moved on.

[0115] Although the unit is equipped with a TDM system, due to a failure in the key phase signal during startup, the TDM system was unable to collect data normally and perform spectrum analysis, so it directly entered the axial displacement analysis.

[0116] From the axial displacement change trend listed in Table 2 above, it can be seen that within 1 minute before the shaft vibration jump, the axial displacement value was -0.08mm at 4:30:57. Within 1 second, the axial displacement suddenly rose to -0.15mm, a change of 0.07mm. The relative change rate was 87.5%, which was greater than 50%, meeting the judgment conditions. Since no spectrum analysis was performed in the previous step, self-excited vibration and radial rubbing were ruled out. It was preliminarily determined that axial rubbing occurred in the turbine rotor, and the next step of analysis was carried out.

[0117] From the active power (load) change trend listed in Table 2 above, it can be seen that within 1 minute before the shaft vibration jump, the active power value was 276MW at 4:30:57. Within 1 second, the active power suddenly dropped to 260MW, a change of 16MW. The relative change rate of the active power before the jump was 5.8%, which is greater than 4%. It is considered that the active power jump amplitude meets the conditions, and it can be determined that the turbine rotor has axial friction.

[0118] From the data in Table 2, it can be seen that the measuring point with the largest radial shaft vibration jump amplitude is shaft vibration No. 1, and the relevant operating parameters of the high-pressure cylinder supported by bearing No. 1 are obtained;

[0119] After the radial vibration jump, it can operate safely and stably at 270MW active power. Obtain the relevant operating parameter data of the high-pressure cylinder after 30 minutes of stable operation at this power. Calculate the characteristic flow area of ​​the stage group and record it as F V2 ;

[0120] Query the historical data before the radial vibration jump, obtain the relevant operating parameter data of the high-pressure cylinder after 30 minutes of stable operation at 270MW power, calculate the characteristic flow area of ​​the stage group and record it as F V1 ;

[0121] Table 3 lists the relevant thermal state parameters and calculation results required for the calculation of the characteristic flow area at 270MW before and after the fault. It can be seen from the calculation of thermal parameters that the characteristic flow area of ​​the main steam valve to the 8th stage extraction steam group decreased by 5.59m before and after the shaft vibration jump. 2 The relative change rate of the characteristic flow area is 11.12%, which is greater than 8%. It is believed that the change amplitude of the characteristic flow area meets the conditions, and it can be determined that the turbine rotor has axial friction.

[0122] Table 3 State parameters and calculation results before and after the fault

[0123]

[0124] Figure 6 The diagram shows the wear of the first three stages of the high-pressure rotor after axial friction. After the high-pressure cylinder was returned to the manufacturer for disassembly, it was found that the internal damage was serious. The first three stages of the high-pressure rotor's moving blade shrouds were in axial contact with the root of the lower stage partition and suffered a severe axial friction failure. Among them, the second stage moving blade top shrouds were seriously damaged. The first seven stages of moving blade top shrouds were all worn to varying degrees. The second to sixth stages of the stator's stators had varying degrees of wear on their steam inlet and steam outlet edges. For the wear situation, please refer to Figure 6 .

[0125] The following are system embodiments of the present disclosure, which can be used to implement the method embodiments of the present disclosure. For details not disclosed in the system embodiments of the present disclosure, please refer to the method embodiments of the present disclosure.

[0126] See Figure 7 , Figure 7 The structural block diagram of the first steam turbine rotor axial rub identification system based on state parameter analysis provided by an embodiment of the present disclosure is shown. The steam turbine rotor axial rub identification system based on state parameter analysis can be implemented as all or part of the system through software, hardware, or a combination of both. The steam turbine rotor axial rub identification system based on state parameter analysis disclosed in the present disclosure can be simply referred to as a steam turbine rotor axial rub identification system or identification system. The steam turbine rotor axial rub identification system 10 includes a shaft vibration processing module 11, a displacement processing module 12, a judgment module 13, a first comprehensive processing module 14, and a second comprehensive processing module 15, wherein:

[0127] The shaft vibration processing module 12 is used to obtain radial shaft vibration data of each measuring point of the shaft system during a preset time period during the operation of the steam turbine, obtain the jump amplitude of multiple measuring points based on the radial shaft vibration data, and then determine whether a shaft vibration jump occurs. If a shaft vibration jump occurs, analyze the trend of the radial shaft vibration data after the jump to determine whether the trend after the shaft vibration jump meets the conditions, and output a satisfaction signal if the conditions are met;

[0128] The displacement processing module 12 is used to obtain the axial displacement data during the operation of the steam turbine after receiving the satisfied signal, and obtain the relative change rate of the axial displacement according to the axial displacement data;

[0129] A judgment module 13 is used to judge whether the steam turbine is equipped with a rotating machinery diagnosis monitoring and management system, and output an equipped signal if the steam turbine is equipped with a rotating machinery diagnosis monitoring and management system, otherwise output a not equipped signal;

[0130] The first comprehensive processing module 14 is configured to, after receiving the equipped signal, obtain a target frequency less than a set frequency and a ratio of the target frequency to the amplitude change of the pass frequency based on the radial shaft vibration data, and perform axial rubbing identification based on the ratio and the relative change rate of the axial displacement;

[0131] The second comprehensive processing module 15 is used to obtain active power data and characteristic flow area after receiving the unequipped signal, obtain the active power relative change rate and area deviation rate based on the active power data and characteristic flow area, and perform axial friction identification based on the axial displacement relative change rate, active power relative change rate and area deviation rate.

[0132] Optionally, the shaft vibration processing module 11 is specifically used to: obtain the jump amplitude of multiple measuring points based on the radial shaft vibration data, determine whether the jump amplitudes of the target measuring point with the largest jump amplitude and the adjacent measuring points of the target measuring point are respectively greater than or equal to the corresponding amplitude thresholds, and if so, a shaft vibration jump occurs; analyze the trend of the radial shaft vibration data after the jump, and determine whether the target measuring point falls back within the first set time, and if so, the trend after the shaft vibration jump meets the conditions.

[0133] Optionally, the displacement processing module 12 is specifically used to: obtain axial displacement data during turbine operation, perform trend analysis on the axial displacement data, determine whether the axial displacement jumps within a second set time before the shaft vibration jump occurs, and if so, obtain the relative change rate of the axial displacement.

[0134] Optionally, Figure 8 FIG. 2 shows a structural block diagram of a second steam turbine rotor axial friction identification system based on state parameter analysis provided by an embodiment of the present disclosure. Figure 8 As shown, the first comprehensive processing module 14 includes a ratio processing unit 141, which is used to use the rotating machinery diagnosis, monitoring and management system to perform spectral analysis on the radial shaft vibration data to determine whether there is a target frequency less than the set frequency, and if so, calculate the ratio of the amplitude change of the target frequency to the amplitude change of the pass frequency.

[0135] Optionally, the first comprehensive processing module 14 is specifically used to: determine whether the ratio is greater than or equal to a proportion threshold; if it is greater than or equal to the proportion threshold, determine whether the relative change rate of the axial displacement is greater than or equal to a first change rate threshold; if it is greater than or equal to the first change rate threshold, axial friction occurs in the turbine rotor.

[0136] Alternatively, as Figure 8 As shown, the second integrated processing module 15 includes a power processing unit 151 and an area processing unit 152, wherein:

[0137] The power processing unit 151 is used to obtain active power data during the operation of the steam turbine, perform trend analysis on the active power data, determine whether the active power jumps within the second set time before the shaft vibration jump occurs, and if so, obtain the relative change rate of the active power;

[0138] The area processing unit 152 is used to determine the bearing with the largest jump amplitude in the shaft vibration jump, obtain the steam flow of the cylinder supported by the bearing, the steam temperature and steam pressure at the steam inlet position, and the steam pressure at the steam extraction port position, calculate the first characteristic flow area and the second characteristic flow area under the same active power before and after the shaft vibration jump, and obtain the area deviation rate based on the first characteristic flow area and the second characteristic flow area.

[0139] Optionally, the second comprehensive processing module 15 is specifically used to: determine whether the relative change rate of axial displacement is greater than or equal to a first change rate threshold; if it is greater than or equal to the first change rate threshold, then determine whether the relative change rate of active power is greater than or equal to a second change rate threshold, and whether the area deviation rate is greater than or equal to the deviation rate threshold; if the relative change rate of active power is greater than or equal to the second change rate threshold and / or the area deviation rate is greater than or equal to the deviation rate threshold, then axial friction occurs in the turbine rotor.

[0140] It should be noted that the steam turbine rotor axial rub identification system based on state parameter analysis provided in the above embodiment only uses the division of the above functional modules as an example when executing the steam turbine rotor axial rub identification method based on state parameter analysis. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the electronic device can be divided into different functional modules to complete all or part of the functions described above. In addition, the steam turbine rotor axial rub identification system based on state parameter analysis provided in the above embodiment and the steam turbine rotor axial rub identification method based on state parameter analysis are of the same concept. The implementation process is detailed in the method embodiment and will not be repeated here.

[0141] The serial numbers of the above-mentioned embodiments of the present disclosure are for description only and do not represent the advantages or disadvantages of the embodiments.

[0142] In the steam turbine rotor axial rubbing identification system based on state parameter analysis of the embodiment of the present disclosure, the shaft vibration processing module obtains radial shaft vibration data during the operation of the steam turbine, and judges whether shaft vibration jump occurs based on the radial shaft vibration data, and whether the trend after the shaft vibration jump meets the conditions. If the conditions are met, the displacement processing module obtains axial displacement data, and then obtains the relative change rate of axial displacement, and judges whether the steam turbine is equipped with a rotating machinery diagnostic monitoring and management system through the judgment module; if equipped, the first comprehensive processing module combines the target frequency less than the set frequency in the radial shaft vibration data, and performs axial rubbing identification based on the ratio of the amplitude change of the target frequency to the pass frequency and the relative change rate of axial displacement; if not equipped, the second comprehensive processing module combines the active power data and the characteristic flow area to perform axial rubbing identification based on the relative change rate of axial displacement, the relative change rate of active power and the area deviation rate. In this case, by collecting the state parameters of the steam turbine such as radial vibration, axial displacement, active power, steam flow, steam pressure, steam temperature, etc. under the operating state for feature analysis, the axial rubbing fault of the steam turbine rotor can be identified in a timely and accurate manner. This method also provides a scientific basis for operators and maintenance personnel to take appropriate countermeasures in advance, preventing damage to the flow passages within the cylinder and the thrust bearings. It offers high accuracy and real-time performance. Furthermore, this method directly utilizes data from the DCS and TDM systems that ship with the steam turbine generator set, eliminating the need for external instrumentation. This method simplifies operation, facilitates on-site implementation, and provides reliable analysis results. It has been used in numerous field trials to accurately diagnose steam turbine rotor axial rubbing faults, ensuring equipment safety while also creating significant economic and social benefits for power plants.

[0143] According to an embodiment of the present disclosure, the present disclosure also provides an electronic device, a readable storage medium, and a computer program product.

[0144] Figure 9 1 is a block diagram of an electronic device for implementing a method for identifying axial rubbing of a steam turbine rotor based on state parameter analysis according to an embodiment of the present disclosure. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smart phones, wearable electronic devices, and other similar computing devices. The components, connections and relationships of the components, and functions of the components shown in the present disclosure are merely examples and are not intended to limit the implementation of the present disclosure as described and / or required in the present disclosure.

[0145] like Figure 9As shown, the electronic device 20 includes a computing unit 21, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) 22 or a computer program loaded from a storage unit 28 into a random access memory (RAM) 23. Various programs and data required for the operation of the electronic device 20 can also be stored in the RAM 23. The computing unit 21, the ROM 22, and the RAM 23 are connected to each other via a bus 24. An input / output (I / O) interface 25 is also connected to the bus 24.

[0146] Multiple components in the electronic device 20 are connected to the I / O interface 25, including an input unit 26, such as a keyboard, a mouse, etc.; an output unit 27, such as various types of displays, speakers, etc.; a storage unit 28, such as a magnetic disk, an optical disk, etc., which is communicatively connected to the computing unit 21; and a communication unit 29, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 29 allows the electronic device 20 to exchange information / data with other electronic devices via a computer network such as the Internet and / or various telecommunication networks.

[0147] The computing unit 21 can be any general-purpose and / or specialized processing component with processing and computing capabilities. Some examples of the computing unit 21 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The computing unit 21 performs the various methods and processes described above, such as executing a method for identifying axial rub of a steam turbine rotor based on state parameter analysis. For example, in some embodiments, the method for identifying axial rub of a steam turbine rotor based on state parameter analysis can be implemented as a computer software program tangibly embodied in a machine-readable medium, such as a storage unit 28. In some embodiments, part or all of the computer program can be loaded and / or installed on the electronic device 20 via the ROM 22 and / or the communication unit 29. When the computer program is loaded into the RAM 23 and executed by the computing unit 21, one or more steps of the method for identifying axial rub of a steam turbine rotor based on state parameter analysis described above can be performed. Alternatively, in other embodiments, the computing unit 21 may be configured in any other appropriate manner (for example, by means of firmware) to execute the steam turbine rotor axial rub identification method based on state parameter analysis.

[0148] Various embodiments of the systems and techniques described above in the present disclosure can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), system-on-chip systems (SOCs), programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system that includes at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0149] The program code for implementing the method of the present disclosure can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device so that when the program code is executed by the processor or controller, the functions / operations specified in the flow chart and / or block diagram are implemented. The program code can be executed entirely on the machine, partially on the machine, as a stand-alone software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0150] In the present disclosure, a machine-readable medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or electronic device. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or electronic device, or any suitable combination of the foregoing. More specific examples of machine-readable storage media may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage electronic device, a magnetic storage electronic device, or any suitable combination of the foregoing.

[0151] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the computer. Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0152] The systems and techniques described herein can be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such back-end components, middleware components, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), the Internet, and a blockchain network.

[0153] A computer system may include a client and a server. The client and server are generally remote from each other and typically interact via a communication network. This client-server relationship is established by computer programs running on the respective computers, establishing a client-server relationship. The server may be a cloud server, also known as a cloud computing server or cloud host, a host product within the cloud computing service ecosystem that addresses the management difficulties and limited scalability of traditional physical hosts and VPS services ("Virtual Private Servers" or simply "VPS"). The server may also be a server in a distributed system or a server integrated with blockchain.

[0154] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this disclosure can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in this disclosure can be achieved. This disclosure is not limited here.

[0155] The above specific embodiments do not constitute a limitation on the scope of protection of this disclosure. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this disclosure shall be included within the scope of protection of this disclosure.

Claims

1. A method for identifying axial friction of a steam turbine rotor based on state parameter analysis, characterized in that: include: Acquire radial shaft vibration data of each measuring point of the shaft system during a preset time period during the operation of the steam turbine, obtain jump amplitudes of multiple measuring points based on the radial shaft vibration data, and then determine whether a shaft vibration jump occurs; if a shaft vibration jump occurs, analyze the trend of the radial shaft vibration data after the jump to determine whether the trend after the shaft vibration jump meets a condition; If the conditions are met, the axial displacement data of the steam turbine during operation is obtained, the relative rate of change of the axial displacement is obtained based on the axial displacement data, and it is determined whether the steam turbine is equipped with a rotating machinery diagnostic monitoring and management system; If yes, a target frequency less than a set frequency and a ratio of the target frequency to the amplitude change of the pass frequency are obtained according to the radial shaft vibration data, and axial rubbing is identified based on the ratio and the relative change rate of the axial displacement; If not, active power data and characteristic flow area are obtained, active power relative change rate and area deviation rate are obtained according to the active power data and the characteristic flow area, and axial rubbing identification is performed based on the axial displacement relative change rate, the active power relative change rate, and the area deviation rate; The step of obtaining a target frequency less than a set frequency and a ratio of the target frequency to the amplitude change of the pass frequency according to the radial shaft vibration data includes: Performing spectrum analysis on the radial shaft vibration data using the rotating machinery diagnosis, monitoring and management system to determine whether there is a target frequency less than a set frequency, and if so, calculating the ratio of the amplitude change of the target frequency to the amplitude change of the pass frequency; The performing of axial rubbing identification based on the ratio and the relative rate of change of the axial displacement includes: Determining whether the ratio is greater than or equal to a proportion threshold; If it is greater than or equal to the proportion threshold, determining whether the relative change rate of the axial displacement is greater than or equal to a first change rate threshold; if it is greater than or equal to the first change rate threshold, axial rubbing occurs in the steam turbine rotor; The acquiring of active power data and characteristic flow area, and obtaining an active power relative change rate and an area deviation rate according to the active power data and the characteristic flow area, includes: Acquire active power data during the operation of the steam turbine, perform trend analysis on the active power data, determine whether the active power jumps within a second set time before the shaft vibration jump occurs, and if so, obtain the relative change rate of the active power; Identify the bearing with the largest jump amplitude in the shaft vibration jump, obtain the steam flow rate of the cylinder supported by the bearing, the steam temperature and steam pressure at the steam inlet, and the steam pressure at the steam extraction port, calculate the first characteristic flow area and the second characteristic flow area at the same active power before and after the shaft vibration jump, and obtain the area deviation rate based on the first characteristic flow area and the second characteristic flow area; The performing of axial rubbing identification based on the relative change rate of the axial displacement, the relative change rate of the active power, and the area deviation rate includes: Determine whether the relative change rate of the axial displacement is greater than or equal to a first change rate threshold; if so, determine whether the relative change rate of the active power is greater than or equal to a second change rate threshold, and whether the area deviation rate is greater than or equal to a deviation rate threshold; If the relative change rate of active power is greater than or equal to the second change rate threshold and / or the area deviation rate is greater than or equal to the deviation rate threshold, axial rubbing occurs in the steam turbine rotor.

2. The method for identifying axial friction of a steam turbine rotor based on state parameter analysis according to claim 1, characterized in that: The step of obtaining the jump amplitudes of multiple measuring points based on the radial shaft vibration data and then determining whether a shaft vibration jump occurs, and if a shaft vibration jump occurs, analyzing the trend of the radial shaft vibration data after the jump to determine whether the trend after the shaft vibration jump meets a condition, includes: Obtaining jump amplitudes of multiple measuring points based on the radial shaft vibration data, and determining whether the jump amplitudes of a target measuring point with the largest jump amplitude and adjacent measuring points of the target measuring point are respectively greater than or equal to corresponding amplitude thresholds, and if so, a shaft vibration jump occurs; The trend of the radial shaft vibration data after the jump is analyzed to determine whether the target measuring point falls back within the first set time. If so, the trend of the shaft vibration after the jump meets the conditions.

3. The method for identifying axial friction of a steam turbine rotor based on state parameter analysis according to claim 1 or 2, characterized in that: The step of obtaining axial displacement data during operation of the steam turbine and obtaining a relative rate of change of the axial displacement according to the axial displacement data includes: Axial displacement data during turbine operation is acquired, trend analysis is performed on the axial displacement data, and it is determined whether the axial displacement jumps within a second set time before the shaft vibration jump occurs. If so, the relative change rate of the axial displacement is obtained.

4. A steam turbine rotor axial friction identification system based on state parameter analysis, characterized in that: include: A shaft vibration processing module is used to obtain radial shaft vibration data of each measuring point of the shaft system during a preset time period during the operation of the steam turbine, obtain the jump amplitude of multiple measuring points based on the radial shaft vibration data, and then determine whether a shaft vibration jump occurs. If a shaft vibration jump occurs, analyze the trend of the radial shaft vibration data after the jump to determine whether the trend after the shaft vibration jump meets the conditions, and output a satisfaction signal if the conditions are met; a displacement processing module, configured to, after receiving the satisfaction signal, obtain axial displacement data during the operation of the steam turbine, and obtain a relative change rate of the axial displacement according to the axial displacement data; A judgment module is used to judge whether the steam turbine is equipped with a rotating machinery diagnosis, monitoring and management system, and outputs an equipped signal if the steam turbine is equipped with a rotating machinery diagnosis, monitoring and management system, otherwise outputs a not equipped signal; a first comprehensive processing module configured to, after receiving the equipped signal, obtain a target frequency less than a set frequency and a ratio of the target frequency to the amplitude change of the pass frequency according to the radial shaft vibration data, and perform axial rubbing identification based on the ratio and the relative change rate of the axial displacement; a second comprehensive processing module, configured to, after receiving the unequipped signal, obtain active power data and a characteristic flow area, obtain an active power relative change rate and an area deviation rate based on the active power data and the characteristic flow area, and perform axial rubbing identification based on the axial displacement relative change rate, the active power relative change rate, and the area deviation rate; The first comprehensive processing module includes: a ratio processing unit, configured to perform spectrum analysis on the radial shaft vibration data using the rotating machinery diagnosis, monitoring and management system, to determine whether there is a target frequency less than a set frequency, and if so, to calculate a ratio of an amplitude change of the target frequency to an amplitude change of the pass frequency; The first comprehensive processing module is specifically used to: Determining whether the ratio is greater than or equal to a proportion threshold; If it is greater than or equal to the proportion threshold, determining whether the relative change rate of the axial displacement is greater than or equal to a first change rate threshold; if it is greater than or equal to the first change rate threshold, axial rubbing occurs in the steam turbine rotor; The second comprehensive processing module includes: a power processing unit for acquiring active power data during the operation of the steam turbine, performing trend analysis on the active power data, determining whether the active power jumps within a second set time before the shaft vibration jump occurs, and if so, obtaining a relative change rate of the active power; an area processing unit, configured to determine the bearing with the largest jump amplitude in the shaft vibration jump, obtain the steam flow rate of the cylinder supported by the bearing, the steam temperature and steam pressure at the steam inlet, and the steam pressure at the steam extraction port, calculate a first characteristic flow area and a second characteristic flow area at the same active power before and after the shaft vibration jump, and obtain an area deviation rate based on the first characteristic flow area and the second characteristic flow area; The second comprehensive processing module is specifically used to: Determine whether the relative change rate of the axial displacement is greater than or equal to a first change rate threshold; if so, determine whether the relative change rate of the active power is greater than or equal to a second change rate threshold, and whether the area deviation rate is greater than or equal to a deviation rate threshold; If the relative change rate of active power is greater than or equal to the second change rate threshold and / or the area deviation rate is greater than or equal to the deviation rate threshold, axial rubbing occurs in the steam turbine rotor.

5. The steam turbine rotor axial friction identification system based on state parameter analysis according to claim 4, characterized in that: The shaft vibration processing module is specifically used to: Obtain jump amplitudes of multiple measuring points based on the radial shaft vibration data, and determine whether the jump amplitudes of a target measuring point with the largest jump amplitude and adjacent measuring points of the target measuring point are respectively greater than or equal to corresponding amplitude thresholds, and if so, a shaft vibration jump occurs; The trend of the radial shaft vibration data after the jump is analyzed to determine whether the target measuring point falls back within the first set time. If so, the trend of the shaft vibration after the jump meets the conditions.

6. The steam turbine rotor axial friction identification system based on state parameter analysis according to claim 4 or 5, characterized in that: The displacement processing module is specifically used to: Axial displacement data during turbine operation is acquired, trend analysis is performed on the axial displacement data, and it is determined whether the axial displacement jumps within a second set time before the shaft vibration jump occurs. If so, the relative change rate of the axial displacement is obtained.

7. An electronic device, characterized in that: include: at least one processor; as well as a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the turbine rotor axial rubbing identification method based on state parameter analysis according to any one of claims 1 to 3.

8. A non-transitory computer-readable storage medium storing computer instructions, wherein: The computer instructions are used to enable the computer to execute the method for identifying axial rubbing of a steam turbine rotor based on state parameter analysis according to any one of claims 1 to 3.

9. A computer program product, comprising a computer program, wherein when executed by a processor, the computer program implements the method for identifying axial rub of a steam turbine rotor based on state parameter analysis according to any one of claims 1 to 3.

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