CN106248385B - A kind of Steam Flow Excited Vibration on Steam Turbine characteristic recognition method - Google Patents
A kind of Steam Flow Excited Vibration on Steam Turbine characteristic recognition method Download PDFInfo
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- CN106248385B CN106248385B CN201610585570.0A CN201610585570A CN106248385B CN 106248385 B CN106248385 B CN 106248385B CN 201610585570 A CN201610585570 A CN 201610585570A CN 106248385 B CN106248385 B CN 106248385B
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- 238000000034 method Methods 0.000 title claims abstract description 29
- 230000005284 excitation Effects 0.000 claims abstract description 50
- 238000001228 spectrum Methods 0.000 claims abstract description 17
- 238000005452 bending Methods 0.000 description 1
- 238000003745 diagnosis Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M15/00—Testing of engines
- G01M15/14—Testing gas-turbine engines or jet-propulsion engines
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M7/00—Vibration-testing of structures; Shock-testing of structures
Abstract
The invention discloses a kind of Steam Flow Excited Vibration on Steam Turbine characteristic recognition methods.Accurately identify that steam flow excitation feature becomes a big difficulty from power frequency component variation at present.Technical scheme of the present invention includes the following steps：The axis obtained in steam turbine zero load to gradually loading procedure shakes signal and gap voltage signal, generates vibration trend figure and rumble spectrum figure；According to the vibration trend figure and rumble spectrum figure, judge in valve opening or closing process, axis shakes signal and whether gap voltage signal low frequency component amplitude has respective change；If it is not, then illustrating unit in case of steam flow excitation failure, it is possible to only be reflected on power frequency component；Judge in valve opening or closing process, axis shakes signal and gap voltage signal power frequency component amplitude and whether phase has respective change；If so, illustrating unit, there are steam flow excitation failures, and occur to show on power frequency component when steam flow excitation.The present invention accurately can identify steam flow excitation feature from power frequency component variation.
Description
Technical field
The present invention relates to Turbine Vibrationfault Diagnosis technical field, especially a kind of Steam Flow Excited Vibration on Steam Turbine feature recognition
Method.
Background technology
In the steam turbine course of work, high pressure cylinder constantly increases into vapour density and steam flow rate, acts on high pressure rotor
Exciting force also increases therewith so that rotor system stability reduces, and can cause steam flow excitation when serious, influences unit safety fortune
Row.
At present it is believed that steam flow excitation shows as low frequency component on frequency spectrum significantly increases, but in unit actual motion
In the process, often will appear steam flow excitation to have occurred and that, but low frequency component does not have the case where significant change, at this time power frequency component at
For the important basis for estimation of steam flow excitation fault identification.However, the variation of power frequency component may be a variety of by imbalance, thermal flexure etc.
Failure causes, and accurately identifies that steam flow excitation feature becomes a big difficulty from power frequency component variation.
Invention content
The technical problem to be solved by the present invention is to overcome the problems of the above-mentioned prior art, provide a kind of for power frequency
The steam flow excitation characteristic recognition method of Component Analysis, accurately to identify steam flow excitation feature from power frequency component variation.
For this purpose, the present invention adopts the following technical scheme that：A kind of Steam Flow Excited Vibration on Steam Turbine characteristic recognition method, including it is as follows
Step：
1) axis obtained in steam turbine zero load to gradually loading procedure shakes signal and gap voltage signal, generates vibration trend
Figure and rumble spectrum figure；
2) according to the vibration trend figure and rumble spectrum figure, judge in valve opening or closing process, axis shakes letter
Number and gap voltage signal low frequency component amplitude whether have respective change；
21) if low frequency component amplitude is there are respective change, illustrate that set steady nargin is poor, steam flow excitation is reflected in power frequency
Probability on component is small, identifies steam flow excitation fault signature by low frequency component, terminates identification；
22) if respective change is not present in low frequency component amplitude, illustrate unit in case of steam flow excitation failure, it is possible to
It is only reflected on power frequency component, needs further analysis and identification；
3) according to the vibration trend figure and rumble spectrum figure, by the feature of power frequency component analysis and identification steam flow excitation,
Judge that unit whether there is steam flow excitation hidden danger.
Further, in step 3), when by the feature of power frequency component analysis and identification steam flow excitation,
First, it is determined that in valve opening or closing process, axis shakes signal and gap voltage signal power frequency component amplitude is
It is no to have respective change；
If 1) power frequency component amplitude does not have respective change, illustrate that uneven steam flow power does not cause rotor system stability
Change, terminate identification；
2) if power frequency component amplitude is there are respective change, illustrate that unit there may be steam flow excitation hidden danger, need into
One step analyzes the reason of power frequency component amplitude variation；
Secondly, according to the vibration trend figure and rumble spectrum figure, judge in valve opening or closing process, axis shakes
Whether signal and gap voltage signal power frequency component phase have respective change；
1) if there are respective changes for power frequency component phase, illustrating unit, there are steam flow excitation hidden danger, and steam flow occurs and swashs
It will be shown on power frequency component when shaking；
If 2) respective change is not present in power frequency component phase, it is that power frequency component amplitude is caused to change to illustrate steam flow excitation not
The reason of, terminate identification.
The present invention carries out phase change analysis for power frequency component, accurately can identify vapour from power frequency component variation
Flow exciting feature.
Description of the drawings
Fig. 1 is Control Stage of Steam Turbine arrangement of nozzles schematic diagram；
Fig. 2 is the flow chart of the present invention；
Fig. 3 is steam turbine 1X time of vibration tendency charts；
Fig. 4 is steam turbine 290MW load 1X spectrograms；
Fig. 5 is steam turbine 290MW load 1X tendency charts；
Fig. 6 is steam turbine 290MW load 1X Waterfall plots.
Specific implementation mode
Steam turbine is the rotating power machinery for converting the energy of steam to mechanical work, dynamic usually as the original of power generation
Machine.
Theoretically, the nozzle that steam is controlled by each high pressure valve of steam turbine（As shown in Figure 1）Into vapour, high pressure valve one
As for there are four, when valve opening, uneven steam flow power can generate additional load on rotor, when uneven steam flow power is enough
When big, the steady running of rotor-support-foundation system is destroyed, and steam flow excitation failure occurs.
When single valve is into vapour, steam flow is to the active force resultant bending moment of rotor and a lateral steam flow power, the transverse direction steam flow
The presence of power makes original bearing load be changed, and bearing characteristics also change therewith, eventually lead to rotor system stability
Change.Therefore, in Steam Turbine gradually loading procedure, unbalanced steam flow power is likely to cause the steam flow excitation of unit.
At present it is believed that steam flow excitation shows as low frequency component on frequency spectrum significantly increases, but in unit actual motion
In the process, often will appear steam flow excitation to have occurred and that, but low frequency component does not have the case where significant change, at this time power frequency component at
For the important basis for estimation of steam flow excitation fault identification.However, the variation of power frequency component may be a variety of by imbalance, thermal flexure etc.
Failure causes, and accurately identifies that steam flow excitation feature becomes a big difficulty from power frequency component variation.
In view of the above-mentioned problems, the present invention provides a kind of steam flow excitation characteristic recognition methods for power frequency component analysis.
With reference to the accompanying drawings of the specification, it elaborates to preferred embodiment.
Fig. 2 is the flow chart of Steam Flow Excited Vibration on Steam Turbine characteristic recognition method of the present invention, is included the following steps：
Step 110：Obtain that the axis in steam turbine zero load to gradually loading procedure shakes signal and gap voltage signal, generation are shaken
Dynamic tendency chart and rumble spectrum figure.
Axis shakes signal and gap voltage signal can be from the supervisory instrument of configuration turbine LP rotors（TSI）It obtains.
Vibration trend figure and rumble spectrum figure are generated by shake signal and gap voltage signal of the axis collected.Utilize two
Figure analyzes the Vibration Condition of rotor, intuitive easy.With reference to figure 3, shake signal tendency chart for axis；With reference to figure 4, shake letter for axis
Number spectrogram.
Step 111：According to the vibration trend figure and rumble spectrum figure, judge in valve opening or closing process, axis
It shakes signal and whether gap voltage signal low frequency component amplitude has respective change, if so, executing step 120；Otherwise, step is executed
130。
In steam turbine gradually loading procedure, the opening time of each valve and aperture are different from, and certainly exist imbalance
On rotor, steam flow excitation is also likely to thus cause steam flow force effect, must keep a close eye on the rotor oscillation situation during this.
Specifically, vibration signal of the Steam Turbine before and after valve opening can be obtained, the Waterfall plot for generating the period is analyzed,
Judge whether shake signal and gap voltage signal low frequency component amplitude of axis with valve event respective change occurs.With reference to figure 6, it is
Axis shakes signal Waterfall plot.
Step 120：If low frequency component amplitude there are respective change, illustrates that set steady nargin is poor, steam flow excitation reflection
Probability on power frequency component is small, can identify steam flow excitation fault signature, end of identification by low frequency component.With reference to figure 4, at this time
3000 rpm of rotor speed, 50 Hz of power frequency, occur larger peak value in spectrogram at 27 Hz, and low frequency component has with valve opening
Large change, illustrates that set steady nargin is poor, steam flow excitation can be obviously reflected on low frequency component, readily identified.
Step 130：If respective change is not present in low frequency component amplitude, illustrate unit in case of steam flow excitation failure,
It is possible that being only reflected on power frequency component, need further to carry out analysis and identification, executes step 131.
Step 131：According to the vibration trend figure and rumble spectrum figure, judge in valve opening or closing process, axis
It shakes signal and whether gap voltage signal power frequency component amplitude has respective change, if so, executing step 140；Otherwise, step is executed
150。
Step 140：If power frequency component amplitude there are respective change, illustrates that unit there may be steam flow excitation hidden danger,
The reason of needing further to analyze the variation of power frequency component amplitude, executes step 141.
With reference to figure 3, about 15:30 points, power frequency component amplitude starts to increase, and about 16:30 points, power frequency component amplitude starts
Reduce, the time point that time point closes with valve opening generally conforms to, and illustrates that there are respective changes for power frequency component amplitude, it is possible to
There are steam flow excitation hidden danger.
Step 141：According to the vibration trend figure and rumble spectrum figure, judge in valve opening or closing process, axis
It shakes signal and whether gap voltage signal power frequency component phase has respective change, if so, executing step 160；Otherwise, step is executed
170。
Step 150：If power frequency component amplitude does not have respective change, illustrate rotor-support-foundation system smooth running, uneven steam flow
Power does not cause the change of rotor system stability, end of identification.
Step 160：If there are respective changes for power frequency component phase, illustrating unit, there are steam flow excitation failures, and occur
It will be shown on power frequency component when steam flow excitation.
With reference to figure 3, it is apparent that the phase of power frequency component and the time point that changing occurs in amplitude are big from tendency chart
Cause it is identical, and valve closing after fall back to stationary value, illustrate that steam flow excitation occurs in unit.
Step 170：If respective change is not present in power frequency component phase, it is to cause power frequency component width to illustrate steam flow excitation not
The reason of value variation, end of identification.
With reference to figure 5, after power frequency component changes, phase change very little, and phase is not when power frequency component is fallen after rise
Stationary value before falling back to, it is the reason of causing power frequency component amplitude to change to illustrate steam flow excitation not.
The foregoing is only a preferred embodiment of the present invention, but scope of protection of the present invention is not limited thereto,
Any one skilled in the art in the technical scope disclosed by the present invention, the change or replacement that can be readily occurred in,
It should be covered by the protection scope of the present invention.Therefore, protection scope of the present invention should be with scope of the claims
Subject to.
Claims (2)
1. a kind of Steam Flow Excited Vibration on Steam Turbine characteristic recognition method, which is characterized in that include the following steps：
1) axis obtained in steam turbine zero load to gradually loading procedure shakes signal and gap voltage signal, generate vibration trend figure and
Rumble spectrum figure；
2) according to the vibration trend figure and rumble spectrum figure, judge in valve opening or closing process, axis shake signal and
Whether gap voltage signal low frequency component amplitude has respective change；
21) if low frequency component amplitude is there are respective change, illustrate that set steady nargin is poor, steam flow excitation is reflected in power frequency component
On probability it is small, pass through low frequency component identify steam flow excitation fault signature, terminate identification；
22) if respective change is not present in low frequency component amplitude, illustrate unit in case of steam flow excitation failure, it is possible to only anti-
It reflects on power frequency component, needs further analysis and identification；
3) judged by the feature of power frequency component analysis and identification steam flow excitation according to the vibration trend figure and rumble spectrum figure
Unit whether there is steam flow excitation hidden danger.
2. Steam Flow Excited Vibration on Steam Turbine characteristic recognition method according to claim 1, which is characterized in that in step 3), pass through
When the feature of power frequency component analysis and identification steam flow excitation,
First, it is determined that in valve opening or closing process, axis shakes signal and whether gap voltage signal power frequency component amplitude has
Respective change；
If 1) power frequency component amplitude does not have respective change, illustrate that uneven steam flow power does not cause changing for rotor system stability
Become, terminates identification；
2) if power frequency component amplitude is there are respective change, illustrate that unit there may be steam flow excitation hidden danger, needs further
The reason of analyzing the variation of power frequency component amplitude；
Secondly, according to the vibration trend figure and rumble spectrum figure, judge in valve opening or closing process, axis shakes signal
Whether there is respective change with gap voltage signal power frequency component phase；
1) if there are respective changes for power frequency component phase, illustrating unit, there are steam flow excitation hidden danger, and when generation steam flow excitation
It will show on power frequency component；
If 2) respective change is not present in power frequency component phase, it is the original for causing power frequency component amplitude to change to illustrate steam flow excitation not
Cause terminates identification.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111692269A (en) * | 2020-05-15 | 2020-09-22 | 华中农业大学 | Boundary identification method of nonlinear vibration isolation system |
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Address after: The eight district of Hangzhou city in Zhejiang province 310014 Huadian Zhaohui under No. 1 Lane Applicant after: Power Science Research Institute of Zhejiang Electric Power Co., Ltd. Applicant after: State Grid Corporation of China Address before: The eight district of Hangzhou city in Zhejiang province 310014 Huadian Zhaohui under No. 1 Lane Applicant before: Electric Power Research Institute of State Grid Zhejiang Electric Power Company Applicant before: State Grid Corporation of China |
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Inventor after: Ying Guangyao Inventor after: Wu Wenjian Inventor after: Wei Chen Inventor after: Zheng Shuiying Inventor after: Liu Shulian Inventor after: Cai Wenfang Inventor after: Li Weijun Inventor before: Ying Guangyao Inventor before: Wu Wenjian Inventor before: Zheng Shuiying Inventor before: Liu Shulian Inventor before: Cai Wenfang Inventor before: Li Weijun |
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