scholarly journals New diagnostic signs of the technical condition of piston compressors on the basis of characteristic function of the vibroacoustic signal

2019 ◽  
Vol 1260 ◽  
pp. 032023
Author(s):  
I S Kudryavtseva ◽  
A P Naumenko ◽  
A I Odinets ◽  
V E Bardanov
Keyword(s):  
Characteristic Function ◽  
Technical Condition ◽  
Vibroacoustic Signal ◽  
Diagnostic Signs

scholarly journals Information Value Measure for Optimization of Flexible Diagnosis Programs of Technical Objects

2019 ◽  
Vol 18 (6) ◽  
pp. 1434-1461 ◽  
Author(s):  
Evgeniy Kopkin ◽  
Igor Kobzarev
Keyword(s):  
A Priori ◽  
Technical Condition ◽  
Diagnostic Information ◽  
Information Value ◽  
Technical State ◽  
A Posteriori ◽  
Automated Systems ◽  
Maximum Value ◽  
Diagnostic Signs ◽  
The Difference

Existing methods of calculating of the value of diagnostic information circulating in the automated systems of monitoring of technical condition of objects do not take into account "losses" ("gains") resulting from making “wrong” decisions when identifying this state. The purpose of the work is to develop an algorithm that allows to solve the problem of recognizing the technical state of the object being analyzed by means of dynamic programming, the value of the diagnostic information as an optimized indicator being used. The solution to the optimization problem of a diagnostic procedure is based on the use of a measure of the information value proposed by R. L. Stratonovich. It is modified according to the subject area of the technical diagnostics and in the case when the diagnostic features presented in the form of intervals on the real numerical axis are used. The maximum value of the diagnostic information is achieved by minimizing the average "losses" (maximizing the average "gains") obtained when performing tests of diagnostic signs in the process of recognizing the technical condition of an object. To solve the problem, a recurrent expression possessing a scientific novelty has been proposed. It allows to calculate the value of the information obtained when performing tests of diagnostic signs in each of the analyzed information states of the diagnostic process. In the process of the diagnostics program implementation when recognizing the technical condition of the object both “losses” and “winnings” are possible. The difference between their a priori and a posteriori means values characterizes the value of the diagnostic information numerically. The magnitude of the information value indication depends on the probabilities of the results of the diagnostic signs checks and is proportional to the difference between the a posteriori and a priori probabilities of achieving the diagnostic goal. By using the proposed solution, it is possible to synthesize the flexible diagnostics program that is optimal according to the maximum value of diagnostic information in the form of a oriented graph or sets of tests in proper sequence of their execution. This is necessary in order to recognize the specific technical state in which the object is located. The implementation of the algorithm developed is possible in the software and algorithmic support of the automated systems for monitoring the state of complex technical objects.

Energy of Vibroacoustic Signal as Parameter of Logistics Model of the Tooth’s Crack Development

2012 ◽  
Author(s):  
Stanisław Radkowski ◽  
Robert Gumiński
Keyword(s):  
Probability Distribution ◽  
Statistical Methods ◽  
Fatigue Damage ◽  
Technical Condition ◽  
Diagnostic Information ◽  
Crack Development ◽  
Vibroacoustic Signal ◽  
Damage Process ◽  
Cracks Propagation ◽  
Development Phases

The paper takes on the issue of uncertainty in statistical methods of cracks propagation. The goal of the paper was to develop a method, which would enable use of diagnostic information in assessment of fatigue damage process. Particular attention was paid to the possibility of forecasting the occurrence of damage due to fatigue while relying on the analysis of the structure of a vibroacoustic signal. The difficulty in this case is that the set of parameters containing diagnostic information may change as defects develop. This fact confirms the necessity of examining the evolution of probability distribution and defining the periods of an object’s operation, carried out while taking into account the actual technical condition as well as the associated identification of defect development phases. The study presents the following issue: developing the method of diagnosing the early stages of defect development while analyzing energy of vibroacoustics signal as parameter of logistics model of cracks development.

Preliminary studies of vibroacoustic signal images in the context of identification of a passing rail vehicle

2018 ◽  
Vol 121 ◽  
pp. 31-40
Author(s):  
Rafał Burdzik ◽  
Paweł Słowiński ◽  
Łukasz Konieczny
Keyword(s):  
Acoustic Pressure ◽  
Technical Condition ◽  
Rail Vehicle ◽  
Rail Vehicles ◽  
Vibroacoustic Signal ◽  
Railway Infrastructure ◽  
Propagation Analysis ◽  
Conducting Research ◽  
New Research ◽  
Vibroacoustic Signals

Passing rail vehicles generate vibrations and noise. In most studies, these phenomena are analyzed in terms of impact on people, the environment and railway infrastructure. However, using the vibroacoustic methodology, generated vibration and noise signals can be treated as information carriers. The vast majority of publications in the field of vibroacoustics analyze the usability of signals to determine the technical condition of machines and systems. For many years Professor Rafał Burdzik has been conducting research in the area of vibration and noise propagation analysis in means of transport. As a result of this work, a new research hypothesis was developed as the ability to identify a vehicle or trainset based on recorded images of vibroacoustic signals. The article presents the results of preliminary tests, during which rail vibrations were recorded in three orthogonal axes and acoustic pressure signals in the axis perpendicular to the railway route.

scholarly journals Remote testing for defects in service high-voltage insalators

2020 ◽  
Vol 22 (2) ◽  
pp. 117-127
Author(s):  
A. V. Golenishchev-Kutuzov ◽  
L. V. Akhmetvaleeva ◽  
G. R. Enikeeva ◽  
D. A. Ivanov ◽  
A. V. Semennikov ◽  
...  
Keyword(s):  
High Voltage ◽  
Technical Condition ◽  
Operating Conditions ◽  
Remote Measurement ◽  
Dielectric Surfaces ◽  
Significant Difference ◽  
Diagnostic Signs ◽  
Tunable Receiver ◽  
Polymer Insulators ◽  
Positive Half

On the basis of the two-channel remote measurement method previously developed at the Department of PES KGEU, a set of characteristics of the PD with the simultaneous use of electromagnetic and acoustic sensors, which allows you to remotely measure and evaluate the technical condition of high-voltage insulators (HVI). The article presents the results of developments in the development of the previously proposed method, which allowed to determine not only the type and location of the defect, but also its size and the degree of influence on the working condition of the VI. Particular attention is paid to the evolution of defects under the influence of overvoltage and other electrophysical processes in operating conditions. In particular, the generation of ultra-large PDs that can create erosion of the dielectric surfaces of defects was recently discovered, and the technical condition of highvoltage polymer insulators was examined. All measurements were performed on an experimental bench by non-contact receiving pulse signals of the PD by an electromagnetic tunable receiver in the range of 50-600 MHz. Their indication and computer processing were carried out in order to determine in each of the discrete intervals of the phase voltage the average values of the number and intensity of PD pulses, which either do not exceed the allowable threshold for the occurrence of defects and their development, in comparison with the reference HVI, or exceed it. Based on the results of preliminary bench tests on model specimens and real HVIs under operating conditions, and the obtained set of PD parameters, diagnostic signs were established that made it possible to determine the type, location of the most dangerous defects and the degree of their influence on the HVI working capacity. At the same time, the presence of the most dangerous defects is determined by the expansion of the phase intervals of PD radiation, a sharp increase in PD in negative half-periods of high voltage compared with positive half-periods, and also by a significant difference in the width and shape of single PD pulses.

scholarly journals ДІАГНОСТИКА ТУРБОКОМПРЕСОРА ДИЗЕЛЬНОГО ДВИГУНА ЗА ДОПОМОГОЮ АНАЛІЗУ ВІБРОАКУСТИЧНОГО СПЕКТРУ

2020 ◽  
pp. 24-33
Author(s):  
Роман Анатолійович Варбанець ◽  
Валентин Григорович Клименко ◽  
Дмитро Степанович Мінчев ◽  
Віталій Іванович Залож ◽  
Владислав Іванович Кирнац ◽  
...  
Keyword(s):  
Diesel Engine ◽  
High Speed ◽  
Accurate Determination ◽  
Rotation Frequency ◽  
Technical Condition ◽  
Measured Signal ◽  
Compressor Blades ◽  
Compressor Wheel ◽  
Experimental Stand ◽  
Vibroacoustic Signal

The method considered in the article consists in the analysis of the vibroacoustic signal generated by the compressor of the gas turbocharger during the operation of the diesel engine under load. Spectral analysis shows that the compressor blades generate vibrations that are always present in the spectrum of the general vibration of a gas turbocharger, regardless of its technical condition. The "blade" harmonic in the spectrum corresponding to these oscillations is determined using the method of limitations. The then calculated instantaneous rotor speed of the turbocharger makes it possible to analyze the amplitude of the fundamental harmonic in the spectrum. For numerical analysis of the amplitude of the fundamental harmonic, the power leakage of the discrete spectrum is eliminated. Further analysis of the amplitude of the fundamental harmonic makes it possible to quickly assess the level of vibration of the rotor during operation. The first part of the experiment was carried out on a ship's main diesel engine 5S60MC at a crankshaft speed of 85 min-1. The recording and analysis of vibroacoustic signals from the TCA 66-20072 turbocharger was carried out. The analysis showed the possibility of highly accurate determination of the rotational speed and the relative amplitude of the turbocharger shaft oscillations. The second part of the experiment was carried out on an experimental stand, which is based on a KamAZ-740.10 engine with an original pressurization system. A turbocharger of the TKR-11 type is used as a pressurization unit. As a result of the experiment, it was shown that the method of diagnosing the operation of a turbocharger, which is based on the analysis of a vibroacoustic signal, can be extended not only to turbochargers of low-speed engines, but also to turbochargers of high-speed diesel engines. In this case, the spectrum of the measured signal contains harmonics, the frequencies of which make it possible to determine the crankshaft rotation frequency. It is also shown that measuring the signal outside the compressor, close to its casing, makes it possible to obtain all the necessary diagnostic parameters as accurately as when measuring the signal directly at the inlet to the compressor wheel. The method can be used in practice. To implement it, a smartphone and a computer with special software are enough. The proposed method can be used as the basis for a system for continuous monitoring of the frequency and vibration level of a marine diesel engine turbocharger.

scholarly journals Use of a convolutional neural network to segment signals of motor operated valves

2021 ◽  
Vol 7 (3) ◽  
pp. 207-213
Author(s):  
Konstantin I. Kotsoyev ◽  
Yevgeny L. Trykov ◽  
Irina V. Trykova
Keyword(s):  
Neural Network ◽  
Convolutional Neural Network ◽  
Nuclear Power ◽  
Technical Condition ◽  
Active Power ◽  
Automated Control ◽  
Diagnostic Signs ◽  
Full Power ◽  
Power Operation ◽  
Opening And Closing

Motor operated valves (MOV) are one of the most numerous classes of the nuclear power plant components. An important issue concerned with the MOV diagnostics is the lack of in-process (online) automated control for the MOV technical condition during full power operation of the NPP unit. In this regard, a vital task is that of the MOV diagnostics based on the signals of the current and voltage consumed during MOV ‘opening’ and ‘closing’ operations. The current and voltage signals represent time series measured at regular intervals. The current (and voltage) signals can be received online and contain all necessary information for the online diagnostics of the MOV status. Essentially, the approach allows active power signals to be calculated from the current and voltage signals, and characteristics (‘diagnostic signs’) to be extracted from particular portions (segments) of the active power signals using the values of which MOVs can be diagnosed. The paper deals with the problem of automating the segmentation of active power signals. To accomplish this, an algorithm has been developed based on using a convolutional neural network.

Efficiency of application of the phase-chronometric method and neurodiagnostics for monitoring the degradation of rolling bearings during operation

2020 ◽  
pp. 43-50
Author(s):  
A.S. Komshin ◽  
K.G. Potapov ◽  
V.I. Pronyakin ◽  
A.B. Syritskii
Keyword(s):  
Life Cycle ◽  
Wavelet Analysis ◽  
Metrological Support ◽  
Rolling Bearing ◽  
Technical Condition ◽  
Measurement Information ◽  
Rolling Bearings ◽  
Vibration Diagnostics ◽  
Bearing Life ◽  
Alternative Approach

The paper presents an alternative approach to metrological support and assessment of the technical condition of rolling bearings in operation. The analysis of existing approaches, including methods of vibration diagnostics, envelope analysis, wavelet analysis, etc. Considers the possibility of applying a phase-chronometric method for support on the basis of neurodiagnostics bearing life cycle on the basis of the unified format of measurement information. The possibility of diagnosing a rolling bearing when analyzing measurement information from the shaft and separator was evaluated.

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