CN105258892A - Vibration fault detection method and apparatus for centrifugal compressor - Google Patents
Vibration fault detection method and apparatus for centrifugal compressor Download PDFInfo
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- CN105258892A CN105258892A CN201510629547.2A CN201510629547A CN105258892A CN 105258892 A CN105258892 A CN 105258892A CN 201510629547 A CN201510629547 A CN 201510629547A CN 105258892 A CN105258892 A CN 105258892A
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- centrifugal compressor
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- shaft center
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Abstract
The invention relates to the technical field of compressors, and discloses a vibration fault detection method and an apparatus for a centrifugal compressor. Vibration signals x (t) and y (t) vertical to each other are acquired in a synchronous manner via two eddy current sensors arranged at mutual vertical directions of the same cross section of the position of a bearing of the centrifugal compressor, a vibration sequence of a preset period is obtained, according to the vibration sequence of the preset period, an axis locus synthesized by x (t) and y (t) is drawn in an X-Y-Z space of the time sequence, and according to the axis locus of the time sequence, vibration faults of the centrifugal compressor can be determined. According to the method and the apparatus, the change condition of the axis locus is visually displayed, and the detection efficiency of the vibration faults is improved.
Description
Technical field
The present invention relates to Compressor Technology field, particularly relate to a kind of centrifugal compressor vibration fault detection method and device.
Background technology
Rotor is the critical piece of compressor, and orbit of shaft center, can the operation conditions of simple, directly perceived, vivid reflection equipment as one of rotating machinery important status flag parameter, it reflects the actual operating state of rotor.Axle center trail is synthesized by the vibration signal of rotor same cross section orthogonal directions, can image the reaction a certain moment axle system whirling motion situation, the limitation of this Chart of axes track to reflect orbit of shaft center consecutive variations situation in a period of time.
In prior art, adopt the vibration signal in one dimension digital signal processing method difference analyzing and processing x direction and y direction, then by the result of all directions analyzing and processing synthesis axle center trail.This characteristic can be summarized as the digital signal adopting the digital signal processing method of one dimension to process two one dimensions respectively, then forms a 2D signal.In fact axle center trail is a 2D signal comprising orthogonal directions (as horizontal direction x and vertical direction y) vibration signal.In the process rotated, axle center trail is not changeless, and prior art only shows orbit of shaft center on two dimensional surface, can not observe axle center trail consecutive variations situation in time.
Summary of the invention
The invention provides a kind of centrifugal compressor vibration fault detection method and device, solve the technical matters can not observing axle center trail consecutive variations situation in a period of time in prior art.
The object of the invention is to be achieved through the following technical solutions:
A kind of centrifugal compressor vibration fault detection method, comprising:
By being arranged on two current vortex sensors of same cross section, centrifugal compressor position of bearings orthogonal directions, mutually perpendicular vibration signal x (t) of synchronous acquisition and y (t);
Obtain the oscillating sequence x of preset time period
1(t), x
2(t), x
3(t) ... x
k(t) and y
1(t), y
2(t), y
3(t) ... y
k(t);
According to the oscillating sequence of described preset time period, according to the sequential orbit of shaft center that drafting x (t) and y (t) synthesize in X-Y-Z space, wherein, corresponding vibration signal x (t) of Y-axis, corresponding vibration signal y (t) of Z axis, X-axis is time shaft t;
According to described orbit of shaft center, judge the vibration fault of described centrifugal compressor.
A kind of centrifugal compressor vibration fault pick-up unit, comprising:
Acquisition module, for two current vortex sensors by being arranged on same cross section, centrifugal compressor position of bearings orthogonal directions, mutually perpendicular vibration signal x (t) of synchronous acquisition and y (t);
Acquisition module, for obtaining the oscillating sequence x of preset time period
1(t), x
2(t), x
3(t) ... x
k(t) and y
1(t), y
2(t), y
3(t) ... y
k(t);
Display module, for the oscillating sequence according to described preset time period, in X-Y-Z space, the orbit of shaft center that x (t) and y (t) synthesize is drawn according to sequential, wherein, corresponding vibration signal x (t) of Y-axis, corresponding vibration signal y (t) of Z axis, X-axis is time shaft t;
Judge module, for according to the described orbit of shaft center in sequential, judges the vibration fault of described centrifugal compressor.
By a kind of centrifugal compressor vibration fault detection method provided by the invention and device, by being arranged on two current vortex sensors of same cross section, centrifugal compressor position of bearings orthogonal directions, mutually perpendicular vibration signal x (t) of synchronous acquisition and y (t), obtain the oscillating sequence of preset time period, according to the oscillating sequence of described preset time period, according to the sequential orbit of shaft center that drafting x (t) and y (t) synthesize in X-Y-Z space, according to described orbit of shaft center, judge the vibration fault of described centrifugal compressor.The present invention shows the situation of change of orbit of shaft center intuitively, improves the detection efficiency of vibration fault.
Accompanying drawing explanation
In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, also can obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is the application scenarios figure of the embodiment of the present invention;
The process flow diagram of a kind of centrifugal compressor vibration fault detection method that Fig. 2 provides for the embodiment of the present invention;
The schematic diagram of a kind of orbit of shaft center that Fig. 3 provides for the embodiment of the present invention;
The schematic diagram that the vibration fault that Fig. 4 provides for the embodiment of the present invention shows on orbit of shaft center;
The structural representation of a kind of centrifugal compressor vibration fault pick-up unit that Fig. 5 provides for the embodiment of the present invention.
Embodiment
For enabling above-mentioned purpose of the present invention, feature and advantage become apparent more, and below in conjunction with the drawings and specific embodiments, the present invention is further detailed explanation.
As the application scenarios figure that Fig. 1 is the embodiment of the present invention, centrifugal compressor vibration fault detection system comprises bearing 110, bearing seat 120, current vortex sensor 130, centrifugal compressor vibration fault pick-up unit 140, wherein, bearing 110 is vibrating mechanism to be detected, current vortex sensor 130 is two, be separately positioned in the orthogonal directions of same cross section, bearing 110 position, can the displacement of Real-time Collection bearing in orthogonal both direction.The embodiment of the present invention, with centrifugal compressor vibration fault pick-up unit 140, is introduced a kind of centrifugal compressor vibration fault detection method, as shown in Figure 2, being comprised:
Step 201, by being arranged on two current vortex sensors of same cross section, centrifugal compressor position of bearings orthogonal directions, mutually perpendicular vibration signal x (t) of synchronous acquisition and y (t);
The oscillating sequence of step 202, acquisition preset time period;
Wherein, the x (t) of preset time period continuous acquisition and multiple numerical value of y (t), the sequence of such as continuous acquisition 10 x (t) and y (t) is respectively x
1(t), x
2(t), x
3(t) ... x
10(t) and y
1(t), y
2(t), y
3(t) ... y
10(t);
Step 203, oscillating sequence according to described preset time period, according to the sequential orbit of shaft center that drafting x (t) and y (t) synthesize in X-Y-Z space;
Wherein, X-Y-Z space is 3 D stereo coordinate, corresponding vibration signal x (t) of Y-axis, and corresponding vibration signal y (t) of Z axis, X-axis is time shaft t, and the orbit of shaft center drawn out as shown in Figure 3.
Step 204, according to the described orbit of shaft center in sequential, judge the vibration fault of described centrifugal compressor.
Wherein, step 204 specifically can also comprise:
Step 204-1, calculate the proper vector of typical orbit of shaft center respectively, described typical orbit of shaft center comprises ellipse, interior 8 and fall 8;
Step 204-2, according to described typical axle center trajectory creation neural network, and carry out neural metwork training, to obtain network parameter;
Step 204-3, calculate the proper vector of described orbit of shaft center;
Step 204-4, the proper vector of described orbit of shaft center substituted in neural network calculate, to judge the type of described orbit of shaft center;
Step 204-5, type according to described orbit of shaft center, judge the vibration fault of described centrifugal compressor
Wherein, step 204-5 specifically can comprise following several situation:
1, when orbit of shaft center is elliptical shape, rotor jitterbug is judged as;
2, when orbit of shaft center is, when falling 8 shape, be judged as misaligning fault;
3, when orbit of shaft center is interior 8 shape, oil film whirl fault is judged as;
4, when becoming large by natural elliptical, and when the direction of major axis and minor axis changes or ellipse locally flattens directly or track is in a mess, be judged as entering foreign matter in described centrifugal compressor.
Using the important information that phase place responds as rotor unbalance in the embodiment of the present invention, the change of phase place means that the non-equilibrium site of rotor changes, and therefore, after step 203, can also comprise:
One by one by the initial position of orbit of shaft center point according to sequential at X-Y-Z space line, to react the situation of change (heavy black line as in the Chart of axes track in Fig. 3) of vibration phase.Correspondingly, according to the situation of change of vibration phase, the vibration fault of described centrifugal compressor can be judged, specifically can comprise:
Judge whether phase place change is greater than predetermined threshold value;
When phase place change is greater than predetermined threshold value, judge described centrifugal compressor generation imbalance fault.
Such as: for flex rotor rise machine cross the critical front and rear of single order want each change 90 °, entire change 180 °, therefore for the flex rotor being operated in more than single order, phase change judges a critical foundation.In addition for operating rotating machinery, find that vibration increases, its phase place also there occurs and changes and exceed predetermined threshold value simultaneously, shows that imbalance fault has appearred in rotor.
A kind of centrifugal compressor vibration fault detection method that the embodiment of the present invention provides, by being arranged on two current vortex sensors of same cross section, centrifugal compressor position of bearings orthogonal directions, mutually perpendicular vibration signal x (t) of synchronous acquisition and y (t), obtain the oscillating sequence of preset time period, according to the oscillating sequence of described preset time period, according to the sequential orbit of shaft center that drafting x (t) and y (t) synthesize in X-Y-Z space, according to the described orbit of shaft center in sequential, judge the vibration fault of described centrifugal compressor.The embodiment of the present invention shows the situation of change of orbit of shaft center intuitively, improves the detection efficiency of vibration fault.And orbit of shaft center of the prior art once can only check an orbit of shaft center, the continuity on not free.
The embodiment of the present invention additionally provides a kind of centrifugal compressor vibration fault pick-up unit, as shown in Figure 5, comprising:
Acquisition module 510, for two current vortex sensors by being arranged on same cross section, centrifugal compressor position of bearings orthogonal directions, mutually perpendicular vibration signal x (t) of synchronous acquisition and y (t);
Acquisition module 520, for obtaining the oscillating sequence x of preset time period
1(t), x
2(t), x
3(t) ... x
k(t) and y
1(t), y
2(t), y
3(t) ... y
k(t);
Display module 530, for the oscillating sequence according to described preset time period, according to the sequential orbit of shaft center that drafting x (t) and y (t) synthesize in X-Y-Z space, wherein, corresponding vibration signal x (t) of Y-axis, corresponding vibration signal y (t) of Z axis, X-axis is time shaft t;
Judge module 540, for according to the described orbit of shaft center in sequential, judges the vibration fault of described centrifugal compressor.
Wherein, display module 530 also for by the initial position of each orbit of shaft center point according to sequential at X-Y-Z space line, to react the situation of change of vibration phase.
Wherein, described judge module 540, specifically for according to the shape of described orbit of shaft center and repeatability, judges the vibration fault of described centrifugal compressor.
Described judge module 540 is concrete also for the situation of change according to vibration phase, judges the vibration fault of described centrifugal compressor.
Through the above description of the embodiments, those skilled in the art can be well understood to the mode that the present invention can add required hardware platform by software and realize, can certainly all be implemented by hardware, but in a lot of situation, the former is better embodiment.Based on such understanding, what technical scheme of the present invention contributed to background technology can embody with the form of software product in whole or in part, this computer software product can be stored in storage medium, as ROM/RAM, magnetic disc, CD etc., comprising some instructions in order to make a computer equipment (can be personal computer, server, or the network equipment etc.) perform the method described in some part of each embodiment of the present invention or embodiment.
Above to invention has been detailed introduction, applying specific case herein and setting forth principle of the present invention and embodiment, the explanation of above embodiment just understands method of the present invention and core concept thereof for helping; Meanwhile, for one of ordinary skill in the art, according to thought of the present invention, all will change in specific embodiments and applications, in sum, this description should not be construed as limitation of the present invention.
Claims (10)
1. a centrifugal compressor vibration fault detection method, is characterized in that, comprising:
By being arranged on two current vortex sensors of same cross section, centrifugal compressor position of bearings orthogonal directions, mutually perpendicular vibration signal x (t) of synchronous acquisition and y (t);
Obtain the oscillating sequence x of preset time period
1(t), x
2(t), x
3(t) ... x
k(t) and y
1(t), y
2(t), y
3(t) ... y
k(t);
According to the oscillating sequence of described preset time period, according to the sequential orbit of shaft center that drafting x (t) and y (t) synthesize in X-Y-Z space, wherein, corresponding vibration signal x (t) of Y-axis, corresponding vibration signal y (t) of Z axis, X-axis is time shaft t;
According to the described orbit of shaft center in sequential, judge the vibration fault of described centrifugal compressor.
2. centrifugal compressor vibration fault detection method according to claim 1, it is characterized in that, the described oscillating sequence according to described preset time period, after drawing the step of the orbit of shaft center that x (t) and y (t) synthesizes, also comprises according to sequential in X-Y-Z space:
By the initial position of multiple orbit of shaft center point according to sequential at X-Y-Z space line, to react the situation of change of vibration phase.
3. centrifugal compressor vibration fault detection method according to claim 1, is characterized in that, described according to the described orbit of shaft center in sequential, judges the vibration fault of described centrifugal compressor, comprising:
Calculate the proper vector of typical orbit of shaft center respectively, described typical orbit of shaft center comprises ellipse, interior 8 and 8;
According to described typical axle center trajectory creation neural network, and carry out neural metwork training, to obtain network parameter;
Calculate the proper vector of described orbit of shaft center;
The proper vector of described orbit of shaft center is substituted in neural network and calculates, to judge the type of described orbit of shaft center;
According to the type of described orbit of shaft center, judge the vibration fault of described centrifugal compressor.
4. centrifugal compressor vibration fault detection method according to claim 1, is characterized in that, the described type according to described orbit of shaft center, judges the vibration fault of described centrifugal compressor, comprising:
When orbit of shaft center is elliptical shape, be judged as rotor jitterbug;
When orbit of shaft center is, when falling 8 shape, be judged as misaligning fault;
When orbit of shaft center is interior 8 shape, be judged as oil film whirl fault;
When becoming large by natural elliptical, and when the direction of major axis and minor axis changes or ellipse locally flattens directly or track is in a mess, be judged as entering foreign matter in described centrifugal compressor.
5. centrifugal compressor vibration fault detection method according to claim 2, is characterized in that, described according to described orbit of shaft center, judges the vibration fault of described centrifugal compressor, comprising:
According to the situation of change of vibration phase, judge the vibration fault of described centrifugal compressor.
6. centrifugal compressor vibration fault detection method according to claim 5, is characterized in that, the described situation of change according to vibration phase, judges the vibration fault of described centrifugal compressor, comprising:
Judge whether phase place change is greater than predetermined threshold value;
When phase place change is greater than predetermined threshold value, judge described centrifugal compressor generation imbalance fault.
7. a centrifugal compressor vibration fault pick-up unit, is characterized in that, comprising:
Acquisition module, for two current vortex sensors by being arranged on same cross section, centrifugal compressor position of bearings orthogonal directions, mutually perpendicular vibration signal x (t) of synchronous acquisition and y (t);
Acquisition module, for obtaining the oscillating sequence x of preset time period
1(t), x
2(t), x
3(t) ... x
k(t) and y
1(t), y
2(t), y
3(t) ... y
k(t);
Display module, for the oscillating sequence according to described preset time period, in X-Y-Z space, the orbit of shaft center that x (t) and y (t) synthesize is drawn according to sequential, wherein, corresponding vibration signal x (t) of Y-axis, corresponding vibration signal y (t) of Z axis, X-axis is time shaft t;
Judge module, for according to the described orbit of shaft center in sequential, judges the vibration fault of described centrifugal compressor.
8. centrifugal compressor vibration fault pick-up unit according to claim 7, is characterized in that, described display module also for by the initial position of multiple orbit of shaft center point according to sequential at X-Y-Z space line, to react the situation of change of vibration phase.
9. centrifugal compressor vibration fault pick-up unit according to claim 7, is characterized in that, described judge module, specifically for according to the shape of described orbit of shaft center and repeatability, judges the vibration fault of described centrifugal compressor.
10. centrifugal compressor vibration fault pick-up unit according to claim 8, is characterized in that, described judge module is concrete also for the situation of change according to vibration phase, judges the vibration fault of described centrifugal compressor.
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Cited By (3)
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| CN114046979A (en) * | 2021-11-16 | 2022-02-15 | 珠海格力电器股份有限公司 | Compressor rotor track testing device and method and compressor system |
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