CN104483121A - Method for sampling and diagnosing position sequences of reciprocating machine - Google Patents

Abstract

The invention discloses a method for sampling and diagnosing position sequences of a reciprocating machine. The method comprises sampling and diagnosing steps as follows: step one, trigger sequences are generated when N Hall sensors uniformly distributed on the side surface of a cylinder are close to a magnetic pole embedded in a piston, an acoustic emission sensor collects an acoustic emission position sequence of a corresponding position domain of each Hall sensor, a vibration acceleration sensor collects a vibration position sequence of a corresponding position domain of each Hall sensor, and an acoustic emission position sequence sampling matrix set and a vibration position sequence sampling matrix set are formed; and step two, according to the acoustic emission position sequence sampling matrix set formed by the acoustic emission position sequences and the vibration position sequence sampling matrix set formed by the vibration position sequences, the health condition of the reciprocating machine is judged in combination of definition of the acoustic emission position sequence sampling matrix set and the vibration position sequence sampling matrix set and diagnosis domains.

Description

The sampling of reciprocating machine position sequence and diagnostic method

Technical field

The present invention relates to mechanical transmission fields, particularly relate to the sampling of a kind of reciprocating machine position sequence and diagnostic method.

Background technology

Reciprocating machine device is widely used in the fields such as industry, medicine and automobile, and reciprocating machine piston crank structure plays a part power maincenter, directly affects the behavior in service of mechanical system as its health status of key parts.Piston crank structure, due to working environments such as height circulation, high rotating speeds, easily causes the faults such as cylinder body scuffing, sliding bearing fault and piston knock, greatly reduces the reliability and stability of reciprocating machine serviceability, bring heavy losses to national economy.

At present, those skilled in the art launch a series of research for reciprocating machine fault diagnosis, be that the reciprocating machine of representative is in malfunction monitoring process with engine, often get its surface vibration signals, noise signal as research object, due to non-stationary, nonlinear properties that the vibration signal of test is very complicated often, in addition, those skilled in the art adopt demodulation techniques, wavelet technique and neural network etc. to process reciprocating machine non-stationary signal.

Aforementioned research method mostly adopts vibration signal as research object in the fault diagnosis of reciprocating machine, but because the strong nonlinearity of reciprocating machine moves, temporally sequential sampling will cause the problems such as piston run location is inaccurate, frequency ambiguity, some time frequency analysis and intelligent method is utilized although existing, but all have some difficulties in realization with in operation, and real-time is poor; Current monitoring method is substantially all overall monitoring method, is diagnosed by time domain parameter or frequency domain character, cannot determine the detailed problem such as abort situation and the order of severity.

Summary of the invention

The present invention is intended at least solve the technical matters existed in prior art, especially innovatively proposes the sampling of a kind of reciprocating machine position sequence and diagnostic method.

In order to realize above-mentioned purpose of the present invention, the invention provides the sampling of a kind of reciprocating machine position sequence and diagnostic method, its key is, reciprocating machine position sequence sampling apparatus comprises: calibrate AE sensor is placed on cylinder body top, cylinder side wall places N number of Hall element, and vibration acceleration sensor fixed by cylinder crankshaft bearing, and internal piston is embedded with fixed magnetic pole, by Hall element location determination signal position sampling territory, wherein N is positive integer;

The step that said apparatus carries out sampling and diagnosing is as follows:

Step 1, the uniform N number of Hall element of side of cylinder block and the magnetic pole be embedded in piston close to time produce triggers sequencer, calibrate AE sensor gathers the acoustic emission position sequence in this Hall element correspondence position sampling territory, vibration acceleration sensor gathers the vibration position sequence in this Hall element corresponding angles position sampling territory, forms acoustic emission position sequence sampling matrix set and vibration position sequential sampling set of matrices;

Step 2, according to the acoustic emission position sequence sampling matrix set that described acoustic emission position sequence is formed, with the vibration position sequential sampling set of matrices that described vibration position sequence is formed, by the sampling matrix set of acoustic emission position sequence and vibration position sequential sampling set of matrices definition Combining diagnosis territory, reciprocating machine health status is judged.

Described reciprocating machine position sequence sampling and diagnostic method, preferably, described step 1 comprises:

Calibrate AE sensor and vibration acceleration sensor gather a fixed position sequence at this Hall element correspondence position territory and Angle Position place, are designated as X respectively ^ijand Y ^ij,

$X^{\mathrm{ij}}=[x_1^{\mathrm{ij}},x_2^{\mathrm{ij}},...,x_p^{\mathrm{ij}}],$

$Y^{\mathrm{ij}}=[y_1^{\mathrm{ij}},y_2^{\mathrm{ij}},...,y_p^{\mathrm{ij}}],$

Wherein i is position field, and 1≤i≤N, j represents number of strokes, and p is calibrate AE sensor sequence samples capacity,

Acoustic emission position sequence constitutional formula XX in single stroke ^j=[X ^1j; X ^2j; X ^nj] and vibration position sample sequence constitutional formula YY ^j=[Y ^1j; Y ^2j; Y ^nj] stroke sampling matrix,

Stroke sampling matrix constantly accumulates and then forms acoustic emission position sampling sequence matrix set XX=(XX on stroke ¹, XX ², XX ³...) and vibration position sample sequence set of matrices YY=(YY ¹, YY ², YY ³...).

Described reciprocating machine position sequence sampling and diagnostic method, preferably, described step 2 comprises:

Acoustic emission position sequence in the sampling matrix set of acoustic emission position sequence and vibration position sequential sampling set of matrices and vibration position sequence are sampled, cycle calculations is carried out according to the position sequence sampling climb rate, obtain climb rate matrix, described climb rate matrix compares with setting threshold value, judges the health status in each signals collecting territory.

Described reciprocating machine position sequence sampling and diagnostic method, preferably, in described step 2, the climb rate comprises:

S21, makes i=1, j=1,

S22, calculates the position sequence sampling climb rate,

$\begin{array}{c}{\mathrm{\δ}}_{\mathrm{ij}}^p={\mathrm{\ω}}_1^p*\mathrm{sigmoid}({\mathrm{RMS}}_{i(j+1)}^p-{\mathrm{RMS}}_{\mathrm{ij}}^p)+{\mathrm{\ω}}_2^p*\mathrm{sigmoid}(K_{i(j+1)}^p-K_{\mathrm{ij}}^p)+\\ {\mathrm{\ω}}_3^p*\mathrm{sigmoid}(W_{i(j+1)}^p-W_{\mathrm{ij}}^p)\end{array},$

Wherein i is territory number, and j represents number of strokes, is acoustic emission signal during p=1, p=2 interval scale vibration signal; RMS represents sequence root-mean-square value, and K represents sequence kurtosis value, and W represents sequence waveform value; Sigmoid function such as formula shown in, field of definition is [-∞ ,+∞], and codomain is [-1 ,+1];

S23, makes j=j+1, judges whether it is have j<N, if so, then returns step S22, otherwise performs step S24;

S24, obtains the climb rate proper vector P of territory i by cycle calculations _i,

P _i＝O ₁*P _i ¹+O ₂*P _i ²＝[δ _i1,δ _i2,…,δ _ij,…]，

Wherein O ₁and O ₂represent Acoustic Emission Sequence and oscillating sequence weights coefficient respectively;

S25, makes i=i+1, judges whether it is have i<M, and wherein M is positive integer, if so, then returns step S24, otherwise performs step S26;

S26, the climb rate proper vector in comprehensive each territory of reciprocating machine forms climb rate matrix P,

Whether in climb rate matrix P, have the climb rate of a continuous L stroke all to exceed setting threshold value, wherein L, if there is this situation, judge that this territory is as malfunction, otherwise be then normal condition if being positive integer;

S27, makes i=i+1, judges whether it is have i<M, if so, then returns step S26, otherwise the health status in record each position territory.

In sum, owing to have employed technique scheme, the invention has the beneficial effects as follows:

1) position sequence sampling avoids because reciprocating machine speed changes the nonlinear shortcoming of the Temporal Sampling brought in the sampling of territory, fixed position;

2) acoustic emission (AE) sensor and location triggered are carried out being coupled and are sampled, the better detail signal observing the local location of reciprocating machine.

3) propose the method for diagnosing faults of position-based sequential sampling, reciprocating machine local health state is monitored.

Additional aspect of the present invention and advantage will part provide in the following description, and part will become obvious from the following description, or be recognized by practice of the present invention.

Accompanying drawing explanation

Above-mentioned and/or additional aspect of the present invention and advantage will become obvious and easy understand from accompanying drawing below combining to the description of embodiment, wherein:

Fig. 1 is reciprocating machine position sequence of the present invention sampling and diagnostic method device schematic diagram;

Fig. 2 is reciprocating machine position sequence of the present invention sampling and diagnostic method schematic flow sheet;

Fig. 3 is reciprocating machine position sequence of the present invention sampling and diagnostic method position field sample coordinate figure;

Fig. 4 is reciprocating machine position sequence of the present invention sampling and diagnostic method diagnosis schematic diagram;

Fig. 5 is reciprocating machine position sequence of the present invention sampling and diagnostic method embodiment schematic diagram;

Fig. 6 is reciprocating machine position sequence of the present invention sampling and diagnostic method diagnosis schematic diagram.

Embodiment

Be described below in detail embodiments of the invention, the example of described embodiment is shown in the drawings, and wherein same or similar label represents same or similar element or has element that is identical or similar functions from start to finish.Being exemplary below by the embodiment be described with reference to the drawings, only for explaining the present invention, and can not limitation of the present invention being interpreted as.

In describing the invention, it will be appreciated that, term " longitudinal direction ", " transverse direction ", " on ", D score, "front", "rear", "left", "right", " vertically ", " level ", " top ", " end " " interior ", the orientation of the instruction such as " outward " or position relationship be based on orientation shown in the drawings or position relationship, only the present invention for convenience of description and simplified characterization, instead of indicate or imply that the device of indication or element must have specific orientation, with specific azimuth configuration and operation, therefore can not be interpreted as limitation of the present invention.

In describing the invention, unless otherwise prescribed and limit, it should be noted that, term " installation ", " being connected ", " connection " should be interpreted broadly, such as, can be mechanical connection or electrical connection, also can be the connection of two element internals, can be directly be connected, also indirectly can be connected by intermediary, for the ordinary skill in the art, the concrete meaning of above-mentioned term can be understood as the case may be.

Fig. 1 is reciprocating mechanism monitoring schematic diagram, and A is oil-feed (gas) mouth, and B is fuel-displaced (gas) mouth, C oil (gas) cylinder cylinder body, D is piston, and E is connecting rod, F is bent axle, and G is the vibration acceleration sensor be arranged on crankshaft bearing, and AE is calibrate AE sensor.Piston run to be evenly arranged between high-low limit N number of Hall element (H1, H2 ..., Hn), internal piston is embedded with fixed magnetic pole, gathers territory by Hall element location determination signal, as shown in " position 1 sample territory ", " position 2 sample territory " etc.

Position sequence sampling principle:

Position sequence sampling principle as shown in Figure 2, the uniform N number of Hall element of side of cylinder block and the magnetic pole be embedded in piston close to time produce triggers sequencer, AE sensor and vibration acceleration sensor gather a fixed position sequence at this Hall element correspondence position territory and Angle Position place, are designated as X respectively _ijand Y _ij, shown in (1), (2), wherein i is position field (1≤i≤N), and j represents number of strokes, and p is sequence samples capacity.

$X^{\mathrm{ij}}=[x_1^{\mathrm{ij}},x_2^{\mathrm{ij}},...,x_p^{\mathrm{ij}}]---\left(1\right)$

$Y^{\mathrm{ij}}=[y_1^{\mathrm{ij}},y_2^{\mathrm{ij}},...,y_p^{\mathrm{ij}}]---\left(2\right)$

In single stroke, AE position sampling sequence and vibration position sample sequence form the stroke sampling matrix of shape such as formula (3), (4),

XX ^j＝[X ^1j；X ^2j；…；X ^Nj] (3)

YY ^j＝[Y ^1j；Y ^2j；…；Y ^Nj] (4)

Stroke sampling matrix constantly accumulates and then forms AE position sampling sequence matrix set and vibration position sample sequence set of matrices XX=(XX on stroke ¹, XX ², XX ³...) and YY=(YY ¹, YY ², YY ³...), effect is as shown in Figure 3; By the sequence matrix set of AE position sampling and vibration position sampling matrix set definition Combining diagnosis territory, reciprocating machine health status is judged, as shown in Figure 4.

Diagnostic method

Based on reciprocating machine position sequence sampling diagnostic method block diagram as shown in Figure 5, first AE and vibration position sequence are sampled in position sequential sampling set of matrices according to the order in stroke and territory, the definition position sequential sampling climb rate is such as formula (5)

$\begin{array}{c}{\mathrm{\&delta;}}_{\mathrm{ij}}^p={\mathrm{\&omega;}}_1^p*\mathrm{sigmoid}({\mathrm{RMS}}_{i(j+1)}^p-{\mathrm{RMS}}_{\mathrm{ij}}^p)+{\mathrm{\&omega;}}_2^p*\mathrm{sigmoid}(K_{i(j+1)}^p-K_{\mathrm{ij}}^p)+\\ {\mathrm{\&omega;}}_3^p*\mathrm{sigmoid}(W_{i(j+1)}^p-W_{\mathrm{ij}}^p)\end{array},$

Wherein i is territory number, and j represents number of strokes, is AE signal during p=1, p=2 interval scale vibration signal; RMS represents sequence root-mean-square value, and K represents sequence kurtosis value, and W represents sequence waveform value; Sigmoid function is such as formula shown in (6), and field of definition is [-∞ ,+∞], and codomain is [-1 ,+1].

$\mathrm{sigmoid}\left(x\right)=\frac{1}{1+e^{-x}}---\left(6\right)$

The climb rate proper vector P of territory i is obtained by cycle calculations _i, shown in (7), wherein O ₁and O ₂represent Acoustic Emission Sequence and oscillating sequence weights coefficient respectively.The climb rate proper vector in comprehensive each territory of reciprocating machine forms climb rate matrix P, shown in (8) and Fig. 6.Monitor in climb rate matrix P or diagnostic graph and whether have the climb rate of continuous 5 strokes all to exceed setting threshold value, record the health status in each territory.According to Fig. 6 diagnostic graph, wherein diagnose legend color darker, represent its health status of reciprocating machine poorer, thus judge its health status.

P _i＝O ₁*P _i ¹+O ₂*P _i ²＝[δ _i1,δ _i2,…,δ _ij,…] (7)

The present invention disclose a kind of reciprocating machine position sequence sampling and diagnostic method overcome reciprocating machine due to speed change bring non-linear, and, acoustic emission (AE) sensor and vibration acceleration sensor are coupled at same position and sample, the detail signal of better observation reciprocating machine local location, propose the reciprocating machine method for diagnosing faults of position-based sequential sampling, rational fast reciprocating machine health status to be monitored.

In the description of this instructions, specific features, structure, material or feature that the description of reference term " embodiment ", " some embodiments ", " example ", " concrete example " or " some examples " etc. means to describe in conjunction with this embodiment or example are contained at least one embodiment of the present invention or example.In this manual, identical embodiment or example are not necessarily referred to the schematic representation of above-mentioned term.And the specific features of description, structure, material or feature can combine in an appropriate manner in any one or more embodiment or example.

Although illustrate and describe embodiments of the invention, those having ordinary skill in the art will appreciate that: can carry out multiple change, amendment, replacement and modification to these embodiments when not departing from principle of the present invention and aim, scope of the present invention is by claim and equivalents thereof.

Claims (4)

1. a reciprocating machine position sequence sampling and diagnostic method, it is characterized in that, reciprocating machine position sequence sampling apparatus comprises: calibrate AE sensor is placed on cylinder body top, cylinder side wall places N number of Hall element, vibration acceleration sensor fixed by cylinder crankshaft bearing, internal piston is embedded with fixed magnetic pole, and by Hall element location determination signal position sampling territory, wherein N is positive integer;

The step that said apparatus carries out sampling and diagnosing is as follows:

Step 1, the uniform N number of Hall element of side of cylinder block and the magnetic pole be embedded in piston close to time produce triggers sequencer, calibrate AE sensor gathers the acoustic emission position sequence in this Hall element correspondence position sampling territory, vibration acceleration sensor gathers the vibration position sequence in this Hall element corresponding angles position sampling territory, forms acoustic emission position sequence sampling matrix set and vibration position sequential sampling set of matrices;

Step 2, according to the acoustic emission position sequence sampling matrix set that described acoustic emission position sequence is formed, with the vibration position sequential sampling set of matrices that described vibration position sequence is formed, by the sampling matrix set of acoustic emission position sequence and vibration position sequential sampling set of matrices definition Combining diagnosis territory, reciprocating machine health status is judged.

2. reciprocating machine position sequence sampling according to claim 1 and diagnostic method, it is characterized in that, described step 1 comprises:

Calibrate AE sensor and vibration acceleration sensor gather a fixed position sequence at this Hall element correspondence position territory and Angle Position place, are designated as X respectively ^ijand Y ^ij,

$X^{\mathrm{ij}}=[x_1^{\mathrm{ij}},x_2^{\mathrm{ij}},...,x_p^{\mathrm{ij}}],$

$Y^{\mathrm{ij}}=[y_1^{\mathrm{ij}},y_2^{\mathrm{ij}},...,y_p^{\mathrm{ij}}],$

Wherein i is position field, and 1≤i≤N, j represents number of strokes, and p is calibrate AE sensor sequence samples capacity,

Acoustic emission position sequence constitutional formula XX in single stroke ^j=[X ^1j; X ^2j; X ^nj] and vibration position sample sequence constitutional formula YY ^j=[Y ^1j; Y ^2j; Y ^nj] stroke sampling matrix,

Stroke sampling matrix constantly accumulates and then forms acoustic emission position sampling sequence matrix set XX=(XX on stroke ¹, XX ², XX ³...) and vibration position sample sequence set of matrices YY=(YY ¹, YY ², YY ³...).

3. reciprocating machine position sequence sampling according to claim 1 and diagnostic method, it is characterized in that, described step 2 comprises:

Acoustic emission position sequence in the sampling matrix set of acoustic emission position sequence and vibration position sequential sampling set of matrices and vibration position sequence are sampled, cycle calculations is carried out according to the position sequence sampling climb rate, obtain climb rate matrix, described climb rate matrix compares with setting threshold value, judges the health status in each signals collecting territory.

4. the reciprocating machine position sequence sampling according to claim 1 or 3 and diagnostic method, it is characterized in that, in described step 2, the climb rate comprises:

S21, makes i=1, j=1,

S22, calculates the position sequence sampling climb rate,

$\begin{array}{c}{\mathrm{\&delta;}}_{\mathrm{ij}}^p={\mathrm{\&omega;}}_1^p*\mathrm{sigmoid}({\mathrm{RMS}}_{i(j+1)}^p-{\mathrm{RMS}}_{\mathrm{ij}}^p)+{\mathrm{\&omega;}}_2^p*\mathrm{sigmoid}(K_{i(j+1)}^p-K_{\mathrm{ij}}^p)+\\ {\mathrm{\&omega;}}_3^p*\mathrm{sigmoid}(W_{i(j+1)}^p-W_{\mathrm{ij}}^p)\end{array},$

Wherein i is territory number, and j represents number of strokes, is acoustic emission signal during p=1, p=2 interval scale vibration signal; RMS represents sequence root-mean-square value, and K represents sequence kurtosis value, and W represents sequence waveform value; Sigmoid function such as formula shown in, field of definition is [-∞ ,+∞], and codomain is [-1 ,+1];

S23, makes j=j+1, judges whether it is have j<N, if so, then returns step S22, otherwise performs step S24;

S24, obtains the climb rate proper vector P of territory i by cycle calculations _i,

P _i＝O ₁*P _i ¹+O ₂*P _i ²＝[δ _i1,δ _i2,…,δ _ij,…]，

Wherein O ₁and O ₂represent Acoustic Emission Sequence and oscillating sequence weights coefficient respectively;

S25, makes i=i+1, judges whether it is have i<M, and wherein M is positive integer, if so, then returns step S24, otherwise performs step S26;

S26, the climb rate proper vector in comprehensive each territory of reciprocating machine forms climb rate matrix P,

Whether in climb rate matrix P, have the climb rate of a continuous L stroke all to exceed setting threshold value, wherein L, if there is this situation, judge that this territory is as malfunction, otherwise be then normal condition if being positive integer;

S27, makes i=i+1, judges whether it is have i<M, if so, then returns step S26, otherwise the health status in record each position territory.