A method for simulating vibration parameters of nuclear power steam turbine

Abstract

The present invention discloses a method for simulating vibration parameters of a nuclear power steam turbine, comprising the following steps: discretizing and sampling original real data, obtaining a fitting function of speed, load, and real-time vibration values ​​of the nuclear power steam turbine by means of logical curve fitting; using real nuclear power steam turbine startup process data as initial values ​​for simulation by a vibration simulation generator, controlling a regulating valve to obtain vibration superposition values ​​under different theoretical operating conditions, wherein the vibration superposition value is a vibration fluctuation value under the same operating condition; using the real-time vibration value under the same operating condition obtained according to the fitting function as a basic vibration value; superimposing the corresponding basic vibration value and the vibration superposition value to obtain a final vibration value under the corresponding operating condition; and using the final vibration value as a vibration data source for a subsequent upper-level analysis server. The nuclear power steam turbine vibration parameter simulation method provided by the present invention organically combines simulation and practical application, thereby improving the accuracy of the final vibration parameter simulation.

Description

Technical Field

[0001] The present invention relates to the technical field of steam turbine monitoring, and in particular to a vibration parameter simulation method for a nuclear power steam turbine. Background Art

[0002] Due to manufacturing and assembly errors, as well as material inhomogeneities, the rotor has mass eccentricity. As the rotor rotates, the centrifugal force caused by this eccentricity acts on the rotor, acting as a periodic excitation force with a frequency equal to the rotor speed, forcing the rotor to vibrate. When the frequency of the excitation force equals the rotor's lateral natural frequency, resonance occurs, and the amplitude increases dramatically. The speed at this point is the rotor's critical speed. Domestic research institutions have conducted research on steam turbine vibration, but most rely on experimental platforms such as MATLAB or LABVIEW to develop mathematical models and transfer functions, conducting computer analysis and research, which falls within the theoretical realm. Power plant control system manufacturers, both domestic and international, such as ABB, Siemens, GE, Emerson, and Mitsubishi, have also conducted research on steam turbine simulation systems, preferring to implement control logic on their own control system hardware platforms. These simulation models are often implemented through simple configuration, simulating speed, power, and valve management. The simulation logic is used to verify the correctness and usability of their own steam turbine control logic, serving as a functional verification and testing tool. This type of simulation is subject to severe limitations. It can only simulate a few simple working conditions, tends to be qualitative analysis, cannot be flexibly combined, and has low accuracy.

[0003] The disclosure of the above background technology content is only used to assist in understanding the inventive concept and technical solution of the present invention. It does not necessarily belong to the prior art of this patent application, nor does it necessarily provide technical guidance. In the absence of clear evidence that the above content has been disclosed before the filing date of this patent application, the above background technology should not be used to evaluate the novelty and creativity of this application. Summary of the Invention

[0004] In order to overcome the shortcomings of the existing technology, the present invention provides a method for simulating vibration parameters of a nuclear power steam turbine. The specific technical solution is as follows: A method for simulating vibration parameters of a nuclear power steam turbine comprises the following steps:

[0005] During the speed-up and load-up process of a nuclear power steam turbine, the original real data is discretized and sampled, and a fitting function of the speed, load and real-time vibration value of the nuclear power steam turbine is obtained by logical curve fitting. The real startup process data of the nuclear power steam turbine is used as the initial value for simulation by a vibration simulation generating device. The vibration simulation generating device obtains vibration superposition values ​​under different theoretical working conditions by controlling a regulating valve. The vibration superposition value is a vibration fluctuation value under the same working condition. The real-time vibration value under the same working condition obtained according to the fitting function is used as the basic vibration value. The corresponding basic vibration value is superimposed with the vibration superposition value to obtain the final vibration value under the corresponding working condition. The final vibration value is used as the vibration data source of a subsequent upper-level analysis server.

[0006] Furthermore, the fitting function is as follows:

[0007] VB 1x =V1(OS)+V2(FT)+VB0

[0008] Where, VB 1x is the final vibration value, VB0 is the basic vibration value, OS is the current speed, FT is the current load, V1 and V2 are the empirical fitting functions of the vibration superposition value.

[0009] Furthermore, the basic vibration values ​​corresponding to the n adjacent time points are averaged and then superimposed with the vibration superposition value corresponding to the last time point to obtain the final vibration value corresponding to the last time point.

[0010] Furthermore, during the simulation, the rotation speed is less than 1500 RMP and the load is less than 0.1 MW.

[0011] Furthermore, the real-time vibration value of the nuclear power steam turbine includes bearing vibration and shaft vibration, and the vibration simulation generating device simulates the vibration conditions of multiple directions of the shaft to obtain corresponding vibration superposition values.

[0012] Furthermore, the hardware of the vibration simulation generating device includes a steam turbine operation simulator cabinet, an operator station and a redundant network.

[0013] Furthermore, the speed and load settings of the vibration simulation generating device during simulation are consistent with the speed and load settings of the nuclear power steam turbine.

[0014] Furthermore, the vibration simulation generating device realizes pressure parameter simulation under bypass fully open, bypass fully closed or boiler feed water working conditions by controlling the regulating valve.

[0015] Furthermore, the working conditions simulated by the vibration simulation generating device include engaging the brake, rushing, warming up, rated speed, speed increase, and loading load.

[0016] Furthermore, the vibration simulation generating device is based on a nuclear power steam turbine DEH control system.

[0017] Compared with the existing technology, the present invention has the following advantages: based on the operating data of a real nuclear power plant turbine, it organically combines simulation and practical application, uses mathematical models as the simulation object, uses real operating data as the basis of simulation, and integrates real scenes of control simulation to achieve closed-loop control while transmitting simulated vibration data, thereby improving the accuracy of the final vibration parameter simulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 1 is a schematic diagram of a process framework of a method for simulating vibration parameters of a nuclear power steam turbine provided by an embodiment of the present invention;

[0019] Figure 2 1 is a schematic diagram of a curve of a fitting function V1 in a method for simulating vibration parameters of a nuclear power steam turbine provided by an embodiment of the present invention;

[0020] Figure 3 1 is a schematic diagram of a curve of a fitting function V2 in a method for simulating vibration parameters of a nuclear power steam turbine provided by an embodiment of the present invention;

[0021] Figure 4 1 is a schematic diagram of the hardware structure of a vibration simulation generating device in a method for simulating vibration parameters of a nuclear power steam turbine provided by an embodiment of the present invention;

[0022] Figure 5 It is a schematic diagram of a simulation interface of a vibration simulation generating device in the nuclear power steam turbine vibration parameter simulation method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0024] It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and the accompanying drawings are used to distinguish similar items and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, such that the embodiments of the present invention described herein can be implemented in sequences other than those illustrated or described herein. Furthermore, the terms "including," "having," and any variations thereof are intended to cover non-exclusive inclusions.

[0025] In one embodiment of the present invention, a method for simulating vibration parameters of a nuclear power steam turbine is provided, comprising the following steps: during the speed increase and load increase process of the nuclear power steam turbine, the original real data is discretized and sampled, and a fitting function of the speed and load and the real-time vibration value of the nuclear power steam turbine is obtained by logical curve fitting; the real startup process data of the nuclear power steam turbine is used as the initial value for simulation by a vibration simulation generating device, the vibration simulation generating device is based on the nuclear power steam turbine DEH control system, and the speed and load settings of the vibration simulation generating device during simulation are consistent with the speed and load settings of the nuclear power steam turbine.

[0026] The vibration simulation generating device obtains vibration superposition values ​​under different theoretical working conditions by controlling the regulating valve. The vibration superposition value is the vibration fluctuation value under the same working condition. The real-time vibration value under the same working condition obtained according to the fitting function is used as the basic vibration value. The corresponding basic vibration value is superimposed with the vibration superposition value to obtain the final vibration value under the corresponding working condition. The final vibration value is used as the vibration data source of the subsequent upper-level analysis server. In a preferred embodiment, the basic vibration values ​​corresponding to n adjacent time points are averaged and then superimposed with the vibration superposition value corresponding to the last time point to obtain the final vibration value corresponding to the last time point.

[0027] During the simulation, the rotation speed is less than 1500 RMP, the load is less than 0.1 MW, and the fitting function is as follows:

[0028] VB 1x =V1(OS)+V2(FT)+VB0

[0029] Where, VB 1x is the final vibration value, VB0 is the basic vibration value, OS is the current speed, FT is the current load, V1 and V2 are the empirical fitting functions of the vibration superposition value.

[0030] Among them, V1(OS) uses the vibration data curve of actual on-site startup, see Figure 2 , for simulation, this curve belongs to the input quantity and can simulate the data of any startup process; V2(FT) uses the vibration data curve of real on-site startup, see Figure 3 , for simulation, this curve belongs to the input quantity and can simulate the data of any startup process.

[0031] In one embodiment of the present invention, see Figure 1The fitting function for real-time vibration values ​​of nuclear power turbines not only incorporates the primary influencing factors, speed and load, into the fitting range but also considers the unit's thermal state. Further fitting is performed based on the collected unit thermal state data and the previously established function formula to obtain a more accurate base vibration value. During the simulation process, the base vibration value is subject to disturbances and requires correction. Disturbance factors primarily include step changes, gradual changes, and sudden increases. The disturbances corresponding to these three disturbances must be superimposed on the base vibration value to obtain a more accurate simulation value, i.e., the final vibration value. This superposition of these three disturbances can be calculated using a theoretical model or set by the operator. For example, during the turbine run-up process, at 800 RPM, the operator clicks to add a step disturbance. The program then superimposes the pre-set step vibration value on the current real-time vibration value. The amplitude and duration of the step can be manually set. The superposition process for other gradual changes and sudden increases is the same as for the step value.

[0032] In one embodiment of the present invention, during the calculation process, a vibration superposition that changes with the speed is simulated based on the changing characteristics of the actual turbine bearing vibration and shaft vibration. The superposition includes step, gradual change, and incremental changes according to the changing characteristics. The vibration simulation is performed on the entire process from turbine lock-up, start-up, warm-up, over-criticality, to rated speed, speed increase and load loading. In addition, the turbine vibration simulation generating device is also designed based on the experience values ​​of previous operations. It can simulate the changing trends of various vibration data during the start-up and start-up process and after loading. At the same time, the simulator also provides a change disturbance function for some parameters, so that the simulation degree is higher and closer to the actual working conditions.

[0033] In one embodiment of the present invention, the vibration simulation generating device is designed according to the matching of the real steam turbine control system to realize the vibration parameter simulation during the startup process of the nuclear power steam turbine. The vibration simulation generating device mainly consists of two parts: the hardware platform and the software system. Among them, the hardware platform adopts the DCS platform commonly used in power plants, and the system adopts the embedded Linux platform. The resources are open, and the intelligent control and big data functions can be seamlessly connected with the system. The software design is based on the domestic mainstream nuclear power steam turbine DEH control system, combined with the actual parameters and operating conditions of the simulation model, and targeted design is carried out. Its monitoring interface can be found in Figure 5 . It mainly realizes steam turbine startup control, grid connection control and various test operations. During the simulation process, it realizes real-time simulation of steam turbine vibration parameters, including bearing vibration and shaft vibration. The vibration simulation generating device simulates the vibration conditions in multiple directions of the shaft to obtain the corresponding vibration superposition value. According to the vibration measurement point arrangement of the nuclear power steam turbine, the data that can be used for vibration simulation are as follows:

[0034] Serial number name Range unit 1 Vibration of axis 1 (X) 0～500 um 2 Vibration of axis 1 (Y) 0～500 um 3 Axis 2 vibration (X) 0～500 um 4 Vibration of axis 2 (Y) 0～500 um 5 Axis 3 vibration (X) 0～500 um 6 Vibration of axis 3 (Y) 0～500 um 7 Vibration of axis 4 (X) 0～500 um 8 Vibration of axis 4 (Y) 0～500 um 9 Vibration of axis 5 (X) 0～500 um 10 Vibration of axis 5 (Y) 0～500 um 11 Vibration of axis 6 (X) 0～500 um 12 Vibration of axis 6 (Y) 0～500 um 13 Vibration of axis 7 (X) 0～500 um 14 Vibration of axis 7 (Y) 0～500 um 15 Axis 8 vibration (X) 0～500 um 16 Vibration of axis 8 (Y) 0～500 um 17 Axis 9 vibration (X) 0～500 um 18 Vibration of axis 9 (Y) 0～500 um 19 No. 1 bearing vibration 0～200 um 20 No. 2 bearing vibration 0～200 um 21 No. 3 bearing vibration 0～200 um 22 No. 4 bearing vibration 0～200 um 23 No. 5 bearing vibration 0～200 um 24 No. 6 bearing vibration 0～200 um 25 No. 7 bearing vibration 0～200 um 26 No. 8 bearing vibration 0～200 um 27 No. 9 bearing vibration 0～200 um

[0035] See also Figure 4 The vibration simulation device hardware includes a steam turbine operation simulator cabinet, an engineer / operator station, and a redundant network. The steam turbine operation simulator cabinet includes a network switch, a cabinet frame, cabinet fans, and cabinet lighting. Vibration parameter simulation is achieved by superimposing basic data with fluctuations. The basic data consists of converted values ​​of speed, load (power), turbine thermal state, and other parameters. Real-time vibration data is then extrapolated using specific calculation formulas.

[0036] The vibration simulation device is designed using a real-world turbine control system platform. This platform can fully replicate the entire turbine startup and load-carrying process, ensuring high realism. During the speed and load ramp-up process, vibration data is discretized and simulated using a logic curve fit to boundary conditions such as speed and power. This simulation process incorporates the aforementioned calculation process. During startup and load-carrying, each parameter is simulated according to the actual unit startup process. Vibration data is simulated using a combination of stability, slight increases, and large increases. The stability data is derived from historical vibration data from actual startups at a nuclear power plant. Under normal circumstances, unit vibration data remains low and stable, with minor fluctuations, consistent with the relatively low vibration values ​​during startup and load-carrying. Under abnormal operating conditions, a vibration value can be manually set to increase slightly or suddenly. This setup simulates several real-world operating conditions with realistic vibration values.

[0037] The nuclear power steam turbine vibration parameter simulation method provided by this invention allows for flexible vibration simulation configuration, simulating vibration variations under different turbine models and operating conditions. It can correlate multiple parameters, such as speed, load, and unit thermal state, demonstrating strong versatility. New input conditions can be added based on actual unit conditions, demonstrating good scalability. It also supports disturbance design input, enabling simulation analysis of abnormal operating conditions and fault reproduction. Designed using a DCS platform, it is identical to a real turbine control system, making it suitable for training and teaching.

[0038] The above description is only a preferred embodiment of the present invention and does not limit the scope of the patent. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present invention, directly or indirectly applied in other related technical fields, is also included in the scope of patent protection of the present invention.

Claims

1. A method for simulating vibration parameters of a nuclear power steam turbine, characterized in that: The following steps are involved: During the speed increase and load increase process of the nuclear power steam turbine, the original real data is discretized and sampled, and a fitting function of the speed, load and the real-time vibration value of the nuclear power steam turbine is obtained by logical curve fitting; the real startup process data of the nuclear power steam turbine is used as the initial value for simulation by a vibration simulation generating device, and the vibration simulation generating device obtains vibration superposition values ​​under different theoretical working conditions by controlling a regulating valve. The vibration superposition value is the vibration value under the same working condition, and the real-time vibration value under the same working condition obtained according to the fitting function is used as the basic vibration value. The corresponding basic vibration value and the vibration superposition value are superimposed to obtain the final vibration value under the corresponding working condition, and the final vibration value is used as the vibration data source of the subsequent upper-level analysis server; The fitting function is in the following form: VB 1x =V1(OS)+V2(FT)+VB0 Where, VB 1x is the final vibration value, VB0 is the basic vibration value, OS is the current speed, FT is the current load, V1 and V2 are the empirical fitting functions of the vibration superposition value.

2. The method for simulating vibration parameters of a nuclear power steam turbine according to claim 1, characterized in that: The basic vibration values ​​corresponding to the n adjacent time points are averaged and then superimposed with the vibration superposition value corresponding to the last time point to obtain the final vibration value corresponding to the last time point.

3. The method for simulating vibration parameters of a nuclear power steam turbine according to claim 1, characterized in that: During the simulation, the rotation speed is less than 1500 RMP and the load is less than 0.1 MW.

4. The method for simulating vibration parameters of a nuclear power steam turbine according to claim 1, characterized in that: The real-time vibration value of the nuclear power steam turbine includes bearing vibration and shaft vibration. The vibration simulation generating device simulates the vibration conditions of multiple directions of the shaft to obtain corresponding vibration superposition values.

5. The method for simulating vibration parameters of a nuclear power steam turbine according to claim 1, characterized in that: The hardware of the vibration simulation generating device includes a steam turbine operation simulator cabinet, an operator station and a redundant network.

6. The method for simulating vibration parameters of a nuclear power steam turbine according to claim 1, characterized in that: The speed and load settings of the vibration simulation generating device during simulation are consistent with the speed and load settings of the nuclear power steam turbine.

7. The method for simulating vibration parameters of a nuclear power steam turbine according to claim 1, characterized in that: The vibration simulation generating device realizes pressure parameter simulation under bypass fully open, bypass fully closed or boiler feed water working conditions by controlling the regulating valve.

8. The method for simulating vibration parameters of a nuclear power steam turbine according to claim 7, characterized in that: The working conditions simulated by the vibration simulation generating device include brake engagement, rush start, warm-up, rated speed, speed increase, and load loading.

9. The method for simulating vibration parameters of a nuclear power steam turbine according to claim 1, characterized in that: The vibration simulation generating device is based on the DEH control system of a nuclear power steam turbine.

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