SU1352392A1 - L.f.discrete=analog vibration analyzer - Google Patents

Abstract

The invention relates to a measurement technique and can be used to diagnose turbo-generators using vibro-acoustic methods. The aim of the invention is to increase the sensitivity and accuracy of the analyzer and to enable the automation of the measurement process. In order to achieve this goal, the device is additionally introduced into the device (L oo ate to with with to

Description

The filter 3, vectorometer 4 is equipped with an ejection coil fed from a separate generator. The drawing also shows the converter 1 analog-code, amplifier 2, fixed coils 5 ° and 6, 7 and 8, and the mobile measuring coil 8 of the vectorometer, the master oscillator 19 of the audio frequency, the driver 11, the frequency divider 12, the functional converter 13 analog-code, generator 14 removal, resonant amplifier 15, regist1

. The invention relates to a measurement technique, in particular to discrete-analog vibration analyzers, and can be applied, for example, to diagnose turbine units using vibro-acoustic methods,

The aim of the invention is to increase the sensitivity and accuracy of the analyzer, as well as to enable the automation of the measurement process.

The goal is achieved by the addition of a tunable filter and a vectorometer to the known low-frequency analyzer. equipped with special removal coils, powered by a separate generator.

The drawing shows a structural diagram of the analyzer.

The analyzer contains an analog-code converter 1 located at the analyzer input, amplifier 2 of the signal under investigation connected to its output, tunable filter 3 connected by one input to the output of amplifier 2, vectorometer 4 including two fixed coils 5 and 6 consisting of included semi-coils, two fixed coils 7 and 8 and a moving measuring coil 9. The analyzer also has a master oscillator 10 of audio frequency, connected through a shaper 1I to the second input of the converter 1 and the divider 12 input, output coupled to an input of a functional code converter 13 analogue.

amplitude rator 16, alarm 17, control unit 18, linearly varying voltage generator 19, adder 20, control element 21, low-pass filter 22, phase detector 23, frequency meter 24, frequency recorder 25, self-adjusting grip position adjustment body 26 phases. The proposed analyzer allows you to automate the measurement process and eliminate errors introduced by the operator. 1 il.

The outputs of the latter are connected respectively to the semi-coils of coils 5 and 6. Coils 7 and 8 are connected to a pick-up generator 14, and measuring coil 9 is connected to the output of filter 3, which is connected via narrowband resonant amplifier I5 to amplitude recorder 16, signaling device 17 and to the input of the control unit 18 associated with its output to the generator 19 of a linearly varying voltage. The output of the latter is connected to the second input of the filter 3 and to one of the inputs of the adder 20, connected via its output through the control element 21 to the input of the generator 10, and the second input through the low-pass filter 22 is connected to the output of the phase detector 23, which the input is connected to the output of the filter 3, and the other to one of the outputs of the converter 13, to which the frequency recorder 25 is also connected to the frequency meter 24. The control element 21, the adder 20, the filter 22 and the phase detector 23 form an adjustment element for the capture band of the phase locked loop system.

The device works as follows.

At the command of the control unit I8, the linearly varying output voltage of the generator 19 sequentially shifts the passband of the tunable filter 3 in the operating frequency range of the analyzer. Simultaneously. The voltage of the generator 19 through the adder 20 and the control element 21 ne

adjusts generator 10, maintaining the frequency of its output voltage close to the frequency of filter 3. When one of the harmonics of the signal under investigation hits the passband of filter 3, its output signal goes to one of the inputs of the phase detector 23, the second input of which receives the cosine component of the reference voltage generated by the functional converter 13. The output signal of the phase detector 23 is determined by the difference between the frequencies of the settings of the filter 3 and the generator 10. When it enters through the filter 22 into the adder 20, the generator Ator 10 adjusts to the frequency of the extracted harmonic to the accuracy of the phase shift, which ensures the fine tuning of the analyzer. In this case, the filter 3 provides a rough selection of the signal. The high selectivity of the analyzer is achieved due to the selective properties of vectorometer 4, the passband of which is 0.1 ... O, 5 Hz. On its coils 5 and 6, from the output of the functional converter 13, unipolar sinusoids and cosinusoids are shifted by 180, respectively, which form along each of the axes of the vectorometer 4 a sinusoidal (cosinusoidal) magnetic field that does not have a constant component and acts on the moving measuring coil 9 , which carries out an exact selection of the signal being studied. Coils 7 and 8 of the vectorometer 4 are powered by the orthogonal points of the pickup generator 14, whose frequency is constant and its value is outside the frequency range. analyzer range. The signal proportional to the amplitude of the selected component of the spectrum and, accordingly, the angle of deflection of the coil 9 under the influence of the frequency of the removal generator 14, is extracted by the resonant amplifier 15 and fed to the amplitude recorder 16, the signaling device 17 and to the input of the control unit 18 functioning as a temporary program device and generating time interval required to measure and record the allocated signal. At the time of reaching the maximum value of the signal at the input of block 18, it pauses the change in the voltage of the generator 19 and thereby

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filter 3 and master oscillator 10 for a time sufficient to register the measured parameters of the component under study. After a predetermined amount of time has passed, the voltage of the generator 19 continues to change until it falls into the passband of filter 3 of the next component of the signal under study. Since the analyzer bandwidth is generally determined by the pickup and hold band of the phase locked loop, to obtain a constant relative quality factor, the pickup band adjustment unit is combined with the frequency tuning unit of the generator 10 in such a way that the increase in the operating frequency of the last pickup band and hold on the self-tuning system increases according to the same law. With a change in the frequency of the generator 10, the frequency of the control pulses from the output of the driver also changes.

11 to one of the inputs of converter 1, which is equivalent to introducing into the measuring channel an analyzer of a low-pass filter with a cut-off frequency changing synchronously the frequency of the master oscillator 10. The output pulses of the driver 11 are also used

for obtaining the mentioned sinusoids and cosine with a reduced divider

12 frequency. Their frequency is measured by a frequency meter 24 and is recorded in the frequency recorder 25.

When the limit of the tuning range is reached, the generator 19 returns to the initial state and thereby returns the filter 3 and the generator 10 to the initial position. In the future, the analysis process is repeated cyclically as described.

Claims (1)

Thus, the proposed analyzer compared to the prototype allows automating the analysis process and, as a result, eliminating the subjective errors introduced by the operator into the measurement results, and also provides automatic registration of the amplitude and frequency of the component that is tuned by the tunable filter. This filter suppresses all interfering harmonics, which increases the sensitivity of the analyzer by 1.5 times. Invention Formula Low-frequency discrete-analog vibration analyzer containing 0 five 0 five 0 five Analogue-series-connected converter — code and amplifier, amplitude recorder and alarm device, a phase-locked loop system containing a series-connected phase detector and a Filter, as well as a control element whose output is connected to the series-connected audio frequency generator, driver, frequency divider, and code converter analog, while the output of the imaging device is also connected to the second input of the converter analog - code, sine and cosine outputs of the converter code - analog of the connection The coils of the coils of the two coils of the vectorometer also contain a moving measuring coil, the input of the cosine coil is connected to the inputs of the phase detector and frequency meter, the output of which is connected to the frequency recorder, with the aim of increasing sensitivity and accuracy, as well as Providing Automation Pro Editor L. Veselovska Compiled by A. Orlov Tehred L. Oliynyk Proofreader V. But ha Order 5562/44 Draw 730 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 The measurement process, the addition of the removal generator, the resonant amplifier, the tunable filter, the control unit, the generator of the linearly varying voltage, and the adder, are additionally introduced into it. The vectorometer is additionally equipped with two removal coils, which are connected to the outputs of the removal generator, the tunable filter is connected with one input to the output of the amplifier of the signal under study, and the output to the second input of the phase detector and to the input of the moving measuring coil of the vectorometer, which is also connected to the input a resonant amplifier, and its output is connected to an amplitude recorder, a signaling device, and an input of a control unit connected by an output to a generator input of a linearly varying voltage, the output of which oedinen .The inputs a second controllable filter and adder, a second input connected to the output of the LPF, and the output - to the input of the control element.