CN104483121B - 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, more particularly, to a kind of reciprocating machine position sequence sampling and diagnostic method.

Background technology

Reciprocating machine device is widely used in the fields such as industry, medicine and automobile, and reciprocating machine piston is bent Handle structure plays a part power maincenter, directly affects the runnability of mechanical system as its health status of key parts Energy.Piston crank structure, due to working environments such as high circulation, high rotating speeds, easily causes cylinder body scuffing, sliding bearing fault and work The faults such as plug engine knock, greatly reduce the reliability and stability of reciprocating machine service behaviour, bring seriously to national economy Loss.

At present, those skilled in the art are directed to a series of research of expansion of reciprocating machine fault diagnosis, with electromotor are The reciprocating machine representing, during malfunction monitoring, often takes its surface vibration signals, noise signal as object of study, by In the often sufficiently complex non-stationary of the vibration signal of test, nonlinear properties, additionally, those skilled in the art are using demodulation Technology, wavelet technique and neutral net etc. are processed to reciprocating machine non-stationary signal.

Aforementioned research method mostly adopts vibration signal as object of study in the fault diagnosis of reciprocating machine, but by In the strong nonlinearity motion of reciprocating machine, sampling in temporal sequence will lead to inaccurate, frequency ambiguity of piston run location etc. Problem although existing but all have some difficult with operation using some time frequency analysis and intelligent method in realization, and in real time Property is poor；Current monitoring method is all overall monitoring method substantially, is diagnosed it is impossible to really by time domain parameter or frequency domain character Determine the detailed problems such as abort situation and the order of severity.

Content of the invention

It is contemplated that at least solving technical problem present in prior art, especially innovatively propose a kind of reciprocating Mechanical location sequential sampling and diagnostic method.

In order to realize the above-mentioned purpose of the present invention, the invention provides a kind of sampling of reciprocating machine position sequence and diagnosis Method, it is it is critical that reciprocating machine position sequence sampling apparatuses include: acoustic emission sensor is placed on cylinder body top, cylinder Body sidewall places n Hall element, and vibration acceleration sensor fixed by cylinder crankshaft bearing, and internal piston is embedded with fixing magnetic Pole, by Hall element location determination signal position sampling domain, wherein n is positive integer；

Said apparatus are sampled and the step that diagnosed is as follows:

Step 1, produces triggering when n uniform Hall element of side of cylinder block is close with the magnetic pole being embedded in piston Sequence, acoustic emission sensor gathers the acoustic emission position sequence in this Hall element correspondence position sampling domain, and acceleration of vibration passes Sensor gathers the vibration position sequence in this Hall element corresponding angles position sampling domain, constitutes acoustic emission position sequence sampling matrix Set and vibration position sequential sampling set of matrices；

Step 2, the acoustic emission position sequence sampling matrix set being formed according to described acoustic emission position sequence, and described shake The vibration position sequential sampling set of matrices that dynamic position sequence is formed, by acoustic emission position sequence sampling matrix set and shake Dynamic position sequence sampling matrix set defines Combining diagnosis domain and reciprocating machine health status is judged.

Described reciprocating machine position sequence sampling and diagnostic method are it is preferred that described step 1 includes:

Acoustic emission sensor and vibration acceleration sensor gather this Hall element correspondence position domain and angular position One fixed position sequence, is 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 represent number of strokes, and p is acoustic emission sensor sequence samples capacity,

Acoustic emission position sequence constitutional formula xx in single stroke^j=[x^1j；x^2j；…；x^nj] and vibration position sampling sequence Row constitutional formula yy^j=[y^1j；y^2j；…；y^nj] stroke sampling matrix,

Stroke sampling matrix constantly accumulates on stroke and then constitutes acoustic emission position sampling sequence matrix set xx= (xx¹,xx²,xx³...) and vibration position sample sequence set of matrices yy=(yy¹,yy²,yy³,…).

Described reciprocating machine position sequence sampling and diagnostic method are it is preferred that described step 2 includes:

To the acoustic emission position in acoustic emission position sequence sampling matrix set and vibration position sequential sampling set of matrices Sequence and vibration position sequence are sampled, and are circulated calculating according to the position sequence sampling climb rate, obtain the rate matrix that climbs, The described rate matrix that climbs is compared with given threshold, judges the health status in each signals collecting domain.

Described reciprocating machine position sequence is sampled with diagnostic method it is preferred that the climb rate includes in described step 2:

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 domain 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, k represents sequence kurtosis value, and w represents sequence waveform value；Sigmoid function such as formula Shown, domain of definition is [- ∞ ,+∞], and codomain is [- 1 ,+1]；

S23, makes j=j+1, judges whether it is to have j < n, if it is, return to step s22, otherwise execution step s24；

S24, obtains climb rate characteristic vector p of domain i by cycle calculations_i,

p_i=o₁*p_i ¹+o₂*p_i ²=[δ_i1,δ_i2,…,δ_ij...],

Wherein o₁And o₂Represent Acoustic Emission Sequence and oscillating sequence weights coefficient respectively；

S25, makes i=i+1, judges whether it is to have i < m, and wherein m is positive integer, if it is, return to step s24, otherwise Execution step s26；

S26, the climb rate characteristic vector in comprehensive each domain of reciprocating machine constitutes the rate matrix p that climbs,

The climb rate whether having continuous l stroke in the rate matrix p that climbs all exceedes given threshold, and wherein l is positive integer, If there is this situation, judge this domain as malfunction, otherwise be then normal condition；

S27, makes i=i+1, judges whether it is to have i < m, if it is, return to step s26, otherwise records each position domain Health status.

In sum, due to employing technique scheme, the invention has the beneficial effects as follows:

1) in fixed position domain, sampling avoids the sequential brought due to reciprocating machine rapid change for position sequence sampling The nonlinear shortcoming of sampling；

2) acoustic emission (ae) sensor carries out coupling sampling with location triggered, more preferably observes the local location of reciprocating machine Detail signal.

3) propose the method for diagnosing faults based on position sequence sampling, reciprocating machine local health state is supervised Survey.

The additional aspect of the present invention and advantage will be set forth in part in the description, and partly will become from the following description Obtain substantially, or recognized by the practice of the present invention.

Brief description

The above-mentioned and/or additional aspect of the present invention and advantage will become from reference to the description to embodiment for the accompanying drawings below Substantially and easy to understand, wherein:

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

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

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

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

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

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

Specific embodiment

Embodiments of the invention are described below in detail, the example of described embodiment is shown in the drawings, wherein from start to finish The element that same or similar label represents same or similar element or has same or like function.Below with reference to attached The embodiment of figure description is exemplary, is only used for explaining the present invention, and is not considered as limiting the invention.

In describing the invention it is to be understood that term " longitudinal ", " horizontal ", " on ", D score, "front", "rear", The orientation of instruction such as "left", "right", " vertical ", " level ", " top ", " bottom " " interior ", " outward " or position relationship are based on accompanying drawing institute The orientation showing or position relationship, are for only for ease of the description present invention and simplify description, rather than the dress of instruction or hint indication Put or element must have specific orientation, with specific azimuth configuration and operation, therefore it is not intended that limit to the present invention System.

In describing the invention, unless otherwise prescribed and limit, it should be noted that term " installation ", " being connected ", " connection " should be interpreted broadly, for example, it may be the connection of mechanical connection or electrical connection or two element internals, can To be to be joined directly together it is also possible to be indirectly connected to by intermediary, for the ordinary skill in the art, can basis Concrete condition understands the concrete meaning of above-mentioned term.

Fig. 1 monitors schematic diagram for reciprocating mechanism, and a is oil-feed (gas) mouth, and b is fuel-displaced (gas) mouth, c oil (gas) cylinder cylinder body, d For piston, e is connecting rod, and f is bent axle, and g is the vibration acceleration sensor being arranged on crankshaft bearing, and ae is voice sending sensor Device.Piston runs and is evenly arranged n Hall element (h1, h2 ..., hn) between high-low limit, and internal piston is embedded with fixing magnetic Pole, gathers domain by Hall element location determination signal, such as shown in " position 1 sampling domain ", " position 2 sampling domain " etc..

Position sequence sampling principle:

Position sequence sampling principle as shown in Fig. 2 n uniform Hall element of side of cylinder block be embedded in piston Magnetic pole close when produce trigger sequence, ae sensor and vibration acceleration sensor gather this Hall element correspondence position domain With a fixed position sequence of angular position, it is designated as x respectively_ijAnd y_ij, as shown in formula (1), (2), wherein i is position field (1 ≤ i≤n), 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 constitute shape such as formula (3), the stroke of (4) Sampling matrix,

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 constitutes ae position sampling sequence matrix set and vibration position on stroke Put sample sequence set of matrices xx=(xx¹,xx²,xx³...) and yy=(yy¹,yy²,yy³...), effect is as shown in Figure 3；Pass through Ae position sampling sequence matrix set and vibration position sampling matrix set define Combining diagnosis domain to reciprocating machine health State judges, as shown in Figure 4.

Diagnostic method

Diagnostic method block diagram based on the sampling of reciprocating machine position sequence is as shown in figure 5, be first according to stroke and domain Order is sampled to ae and vibration position sequence in position sequential sampling set of matrices, defines the position sequence sampling climb rate 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 domain 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, k represents sequence kurtosis value, and w represents sequence waveform value；Shown in sigmoid function such as formula (6), domain of definition be [- ∞, + ∞], codomain is [- 1 ,+1].

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

Obtain climb rate characteristic vector p of domain i by cycle calculations_i, as shown in formula (7), wherein o₁And o₂Represent sound respectively Transmitting sequence and oscillating sequence weights coefficient.The climb rate characteristic vector in comprehensive each domain of reciprocating machine constitutes the rate matrix that climbs P, as shown in formula (8) and Fig. 6.Monitor whether that the climb rate of continuous 5 strokes all exceedes in climb rate matrix p or diagnostic graph Given threshold, records the health status in each domain.According to Fig. 6 diagnostic graph, wherein diagnosis legend color is deeper, represents reciprocating Its health status mechanical are poorer, thus judging its health status.

p_i=o₁*p_i ¹+o₂*p_i ²=[δ_i1,δ_i2,…,δ_ij,…] (7)

The present invention discloses a kind of reciprocating machine position sequence sampling and diagnostic method overcomes reciprocating machine due to speed It is non-linear that change brings, and, acoustic emission (ae) sensor is coupled sampling with vibration acceleration sensor in same position, More preferably observe the detail signal of reciprocating machine local location, propose the reciprocating machine fault diagnosis based on position sequence sampling Reciprocating machine health status are quickly reasonably monitored by method.

In the description of this specification, reference term " embodiment ", " some embodiments ", " example ", " specifically show The description of example " or " some examples " etc. means specific features, structure, material or the spy describing with reference to this embodiment or example Point is contained at least one embodiment or the example of the present invention.In this manual, to the schematic representation of above-mentioned term not Necessarily refer to identical embodiment or example.And, the specific features of description, structure, material or feature can be any One or more embodiments or example in combine in an appropriate manner.

Although an embodiment of the present invention has been shown and described, it will be understood by those skilled in the art that: not Multiple changes, modification, replacement and modification can be carried out to these embodiments in the case of the principle of the disengaging present invention and objective, this The scope of invention is limited by claim and its equivalent.

Claims (4)

1. a kind of reciprocating machine position sequence sampling and diagnostic method are it is characterised in that reciprocating machine position sequence is sampled Device includes: acoustic emission sensor is placed on cylinder body top, and cylinder side wall places n Hall element, and cylinder crankshaft bearing is solid Determine vibration acceleration sensor, internal piston is embedded with fixed magnetic pole, by Hall element location determination signal position sampling domain, its Middle n is positive integer；

Said apparatus are sampled and the step that diagnosed is as follows:

Step 1, produces triggering sequence when n uniform Hall element of side of cylinder block is close with the magnetic pole being embedded in piston Row, acoustic emission sensor gathers the acoustic emission position sampling sequence in this Hall element correspondence position sampling domain, acceleration of vibration The vibration position sample sequence in this Hall element corresponding angles position sampling domain of sensor acquisition, constitutes acoustic emission position sampling sequence Column matrix set and vibration position sample sequence set of matrices；

Step 2, the acoustic emission position sampling sequence matrix set being formed according to described acoustic emission position sampling sequence, and described shake The vibration position sample sequence set of matrices that dynamic position sampling sequence is formed, by acoustic emission position sampling sequence matrix set with And vibration position sample sequence set of matrices defines Combining diagnosis domain and reciprocating machine health status is judged.

2. reciprocating machine position sequence according to claim 1 sampling and diagnostic method are it is characterised in that described step 1 includes:

Acoustic emission sensor and vibration acceleration sensor gather of this Hall element correspondence position domain and angular position Fixed position sequence, is designated as x respectively^ijAnd y^ij,

$x^{ij}=\&lsqb;x_1^{ij},x_2^{ij},...,x_p^{ij}\&rsqb;,$

$y^{ij}=\&lsqb;y_1^{ij},y_2^{ij},...,y_p^{ij}\&rsqb;,$

Wherein i is position field, and 1≤i≤n, j represent number of strokes, and p is acoustic emission sensor sequence samples capacity, in single stroke Interior acoustic emission position sampling Sequence composition formula xx^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 on stroke and then constitutes acoustic emission position sampling sequence matrix set xx=(xx¹, xx²,xx³...) and vibration position sample sequence set of matrices yy=(yy¹,yy²,yy³,…).

3. reciprocating machine position sequence according to claim 1 sampling and diagnostic method are it is characterised in that described step 2 include:

To the acoustic emission position sampling in acoustic emission position sampling sequence matrix set and vibration position sample sequence set of matrices Sequence and vibration position sample sequence are sampled, and are circulated calculating according to the position sequence sampling climb rate, obtain the climb rate Matrix, the described rate matrix that climbs is compared with given threshold, judges the health status in each signals collecting domain.

4. reciprocating machine position sequence according to claim 3 sampling and diagnostic method are it is characterised in that described step In 2, the climb rate includes:

S21, makes i=1, j=1,

S22, calculates the position sequence sampling climb rate,

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

Wherein i is domain 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, k represents sequence kurtosis value, and w represents sequence waveform value；Sigmoid function such as formulaIt is shown, Domain of definition is [- ∞ ,+∞], and codomain is [- 1 ,+1]；

S23, makes j=j+1, judges whether it is to have j < n, if it is, return to step s22, otherwise execution step s24；

S24, obtains climb rate characteristic vector p of domain i by cycle calculations_i,

$p_i=o_1*p_i^1+o_2*p_i^2=\&lsqb;{\mathrm{\&delta;}}_{i1},{\mathrm{\&delta;}}_{i2},...,{\mathrm{\&delta;}}_{ij},...\&rsqb;,$

Wherein o₁And o₂Represent Acoustic Emission Sequence and oscillating sequence weights coefficient respectively；

S25, makes i=i+1, judges whether it is to have i < m, and wherein m is positive integer, if it is, return to step s24, otherwise executes Step s26；

S26, the climb rate characteristic vector in comprehensive each domain of reciprocating machine constitutes the rate matrix p that climbs,

The climb rate whether having continuous l stroke in the rate matrix p that climbs all exceedes given threshold, and wherein l is positive integer, if depositing Then judge this domain as malfunction in this situation, otherwise be then normal condition；

S27, makes i=i+1, judges whether it is to have i < m, if it is, return to step s26, otherwise records the health in each position domain State.