CN111380607A - Motor vibration or noise frequency detection device and method thereof - Google Patents
Motor vibration or noise frequency detection device and method thereof Download PDFInfo
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- CN111380607A CN111380607A CN201811622528.7A CN201811622528A CN111380607A CN 111380607 A CN111380607 A CN 111380607A CN 201811622528 A CN201811622528 A CN 201811622528A CN 111380607 A CN111380607 A CN 111380607A
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- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H17/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves, not provided for in the preceding groups
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Abstract
The invention discloses a motor vibration or noise frequency detection device and a method thereof, wherein a processing unit and a frequency sensing unit are utilized to process a quantized time domain signal, a frequency domain result is obtained by operation, a characteristic amplitude is taken from the frequency domain result, the characteristic amplitude is set as a trigger amplitude, and the size of the amplitude to be detected is compared to be used for operation or event trigger. The invention is used for the motor device, detects time domain abnormity, improves the power consumption of long-time frequency domain detection, can monitor the health condition of the motor for a long time under the power supply of a battery, and avoids the serious loss of a production line caused by non-early warning shutdown.
Description
Technical Field
The present invention relates to a method and a device for detecting a motor fault, and more particularly, to a device and a method for detecting a vibration or noise frequency of a motor.
Background
A motor, an electric motor or an electric motor is an electrical apparatus that converts electrical energy into mechanical energy, and reuses the mechanical energy to generate kinetic energy for driving other devices.
Common motor failure detection methods include: a multi-sensor detection method, a vibration sensing method, a noise sensing method, and the like.
The multi-sensor detection method uses a plurality of sensors to respectively sense the vibration, noise and temperature of the motor, and then predicts the fault condition of the motor according to the sensed vibration, noise and temperature. The vibration sensing method obtains a vibration signal of the motor, then carries out frequency spectrum analysis on the vibration signal of the sensor to obtain frequency spectrum characteristics, and the frequency spectrum characteristics are interpreted to obtain the fault type of the motor. The noise sensing method obtains the noise signal of the motor, analyzes the frequency spectrum of the noise signal to obtain the frequency spectrum characteristic, and judges the frequency spectrum characteristic to obtain the fault type of the motor.
In the above-described motor failure detection methods, the failure detection is performed for the motor at intervals of twenty-four hours per day. Although these methods can detect a failure of the motor, if the motor is powered by a battery and the failure detection is continuously performed, the operation power is high, and the battery life is rapidly exhausted. Therefore, the invention uses a simple time domain motor sensing method to judge the motor failure and then matches with a complete fault detection method, thereby becoming a research and development direction for improving the existing detection technology and prolonging the service life of the battery.
Disclosure of Invention
In order to improve the deficiency of large amount of computing power consumed by the prior art motor fault detection method, the invention provides a motor vibration or noise frequency detection device, which comprises: a processing unit; and a frequency sensing unit electrically connected to the processing unit; wherein the processing unit quantizes the time domain signal retrieved from the frequency sensing unit at a sampling frequency (step S1); operating the quantized time domain signal to obtain a frequency domain result (step S2); setting a characteristic frequency according to the frequency domain result, and setting a target sampling frequency at least twice as high as the characteristic frequency (step S3); taking the maximum signal value as the starting point of sampling within the first N periods of the time domain signal (step S4), where N is at least one period; sampling the time domain signal according to the sampling start point and the target sampling frequency, calculating a characteristic amplitude, and setting a trigger amplitude according to the characteristic amplitude (step S5); waiting for a set delay time (step S6); quantizing the time domain signal to be measured with the sampling frequency, and taking the maximum signal value as the initial sampling point to be measured within the beginning N periods of the time domain signal to be measured (step S7), wherein N is at least one period; sampling the time domain signal to be measured according to the sampling start point and the target sampling frequency, and calculating the amplitude to be measured (step S8); and determining whether the amplitude to be measured is lower than the trigger amplitude, if so, performing step S1 or a trigger event, otherwise, performing step S6 (step S9).
The invention also provides a method for detecting the vibration or noise frequency of a motor, which comprises the following steps: step S1, quantizing the time domain signal with the sampling frequency; step S2, the quantized time domain signal is operated to obtain a frequency domain result; step S3, setting a characteristic frequency according to the frequency domain result, and setting the frequency at least twice as high as the characteristic frequency as a target sampling frequency; step S4, taking the maximum value of the time domain signal as the starting point of sampling within N periods, where N is at least one period; step S5, sampling the time domain signal according to the sampling start point and the target sampling frequency, calculating a characteristic amplitude, and setting a trigger amplitude according to the characteristic amplitude; step S6, waiting for a set delay time; step S7, quantizing the time domain signal to be tested with the sampling frequency, taking the maximum signal value as the sampling start point to be tested in N periods beginning with the time domain signal to be tested, wherein N is at least one period; step S8, sampling the time domain signal to be tested according to the sampling start point and the target sampling frequency, and calculating the amplitude to be tested; step S9, judging whether the amplitude to be measured is lower than the triggering amplitude, if yes, executing the step S1 or triggering event; if not, the process proceeds to step S6.
Drawings
Fig. 1 is a schematic view of a motor vibration or noise frequency detection apparatus according to the present invention.
FIG. 2 is a flow chart of a method for detecting vibration or noise frequency of a motor according to the present invention.
Fig. 3 is a waveform diagram illustrating a quantized time domain result.
Fig. 4 is a waveform diagram illustrating the quantized time domain result is calculated into a frequency domain result.
Fig. 5 is a waveform diagram illustrating a method of taking a maximum value of the time domain signal as a sampling starting point within N periods, performing double sampling according to the characteristic frequency, calculating a characteristic amplitude, and setting a trigger amplitude according to the characteristic amplitude.
Fig. 6 is a waveform diagram illustrating a quantized time-domain signal to be measured, taking a maximum value of the quantized time-domain signal within N periods as a sampling start point, and sampling twice the characteristic frequency with the maximum value.
Fig. 7 is a schematic waveform diagram illustrating a time domain signal to be measured after quantizing the time domain signal to be measured and determining whether the amplitude to be measured is lower than the trigger amplitude.
Description of the symbols
10 energy management unit
11 processing unit
12 radio interface
13 frequency sensing unit
130 vibration sensing module
131 temperature sensing module
132 noise sensing module
14 energy storage unit
15 antenna unit
A first characteristic frequency
B second characteristic frequency
C third characteristic frequency
D original time domain signal
Sampling waveform of E12 kSPS sampling frequency
Starting point for sampling of F2 kSPS sampling frequency
Sampling waveform of G2 kSPS sampling frequency
Baseline of H2 kSPS sampled waveform
I-superposition waveform
J original time domain signal to be measured
Sampling starting point of O2 kSPS sampling frequency
K quantized time domain signal to be measured
Sampling waveform of L2 kSPS sampling frequency
Baseline of M2 kSPS sampled waveform
N-superposition waveform
P region
S1-S9
Detailed Description
Referring to fig. 1, the present invention is a motor vibration or noise frequency detection device, which includes an energy management unit 10, a processing unit 11, a wireless interface 12, a frequency sensing unit 13, an energy storage unit 14, and an antenna unit 15.
The energy management unit 10 is electrically connected to the processing unit 11. The processing unit 11 is electrically connected to the wireless interface 12. The energy storage unit 14 is electrically connected to the energy management unit 10. The antenna unit 15 is electrically connected to the wireless interface 12.
The frequency sensing unit 13 is disposed on the motor device, and the frequency sensing unit 13 at least has a vibration sensing module 130 and a noise sensing module 132, and may further include a temperature sensing module 131.
The vibration sensing module 130, the temperature sensing module 131 and the noise sensing module 132 are electrically connected to the processing unit 11. The energy storage unit 14 stores electric energy and supplies the electric energy to the energy management unit 10.
The frequency sensing unit 13 is applied to a motor device, the processing unit 11 sets a sampling frequency and a set sampling frequency to sample a time domain signal of the vibration sensing module 130 or the noise sensing module 132, and obtain a quantized time domain result, and then calculates the quantized time domain result into a frequency domain result by a fourier transform method, and takes a frequency with the maximum intensity of the frequency domain result as a characteristic frequency, and finds a maximum value of the signal in at least one period of the start of the quantized time domain result, and sets a target sampling frequency between more than one time of the characteristic frequency and the set sampling frequency when the maximum value of the signal starts, and obtains a characteristic time domain result by the target sampling frequency, and then calculates a characteristic amplitude by the characteristic time domain result, and the characteristic amplitude determines a trigger amplitude for calculation or event trigger.
The frequency domain result, the characteristic frequency, the target sampling frequency, the characteristic time domain result, and the characteristic amplitude obtained by the processing unit 11 are transmitted to the corresponding device through the wireless interface 12 and the antenna unit 15 for reception.
Referring to fig. 2, the present invention is a method for detecting vibration or noise frequency of a motor, comprising the steps of:
in step S1, the time domain signal is quantized with the sampling frequency.
Please refer to fig. 3, which is a schematic diagram of waveforms of quantized time domain signals. For example, the original time-domain signal D (fig. 3 top) is sampled by 12kSPS (Samples Per Second), and a quantized time-domain signal E (fig. 3 bottom) with a sampling frequency of 12kSPS is obtained.
Step S2, the quantized time domain signal is operated to obtain a frequency domain result. The processing unit 11 computes the quantized time domain signal into a frequency domain result by a fourier transform method.
Please refer to fig. 4, which is a waveform diagram illustrating the quantized time domain result being calculated into a frequency domain result. The quantized time domain signal E with the sampling frequency of 12kSPS in fig. 3 is subjected to fourier transform operation to obtain a frequency domain result.
Step S3, setting a characteristic frequency according to the frequency domain result, and setting a target sampling frequency at least twice as high as the characteristic frequency. Referring to fig. 4, the processing unit 11 takes the frequency at which the intensity of the frequency domain result is the maximum as the characteristic frequency, so the frequency at which the maximum intensity is obtained is set as the first characteristic frequency a, which is 1 kHz. Similarly, the second characteristic frequency B and the third characteristic frequency C are also the frequencies of the second maximum intensity and the third maximum intensity.
In step S4, the maximum value of the time domain signal is taken as the starting point of sampling within N periods, where N is at least one period.
Referring to fig. 5 again, for example, the quantized time domain signal E of the signal takes the maximum value of the signal as the starting point F of sampling within the first N cycles of the 12kSPS sampling frequency.
Step S5, sample the time domain signal according to the sampling start point and the target sampling frequency and calculate the characteristic amplitude, and set the trigger amplitude according to the characteristic amplitude. The processing unit 11 sets a target sampling frequency according to at least one time of the characteristic frequency (for example, 2kHz multiplied by 2kHz of the characteristic frequency 1kHz is a target sampling frequency) from the maximum peak of the quantized time domain signal E, obtains a characteristic time domain result through the target sampling frequency, calculates a characteristic amplitude through the characteristic time domain result, and sets a trigger amplitude with the characteristic amplitude.
Please refer to fig. 5, which is a waveform diagram illustrating a trigger amplitude according to the target sampling frequency and a characteristic amplitude calculated by taking a maximum signal value as a sampling start point F in N cycles of the (quantized) time-domain signal E. The quantized time domain signal E of 12kSPS sampling frequency of fig. 3 is sampled with 2kSPS, resulting in the sampling waveform G of 2kSPS sampling frequency of fig. 5. The sampling waveform G with the sampling frequency of 2kSPS takes a phase of 180 degrees, and then a half frequency of 1kSPS is used for calculating to obtain a base line (Baseline) H of the sampling waveform of 2 kSPS. And further calculating a sampling waveform G of the 2kSPS sampling frequency and a base line H of the 2kSPS sampling waveform into a superposition waveform I, and referring to the maximum amplitude value of the superposition waveform I for a period of time to obtain the characteristic amplitude. And referring to the characteristic amplitude, setting the characteristic amplitude value less than or equal to the characteristic amplitude value as a trigger amplitude.
In step S6, a set delay time is waited. The processing unit 11 waits for a set delay time.
Step S7, quantize the time domain signal to be measured, and take the maximum signal value as the sampling start point to be measured in the beginning N cycles of the time domain signal to be measured, where N is at least one cycle. The processing unit 11 samples the time domain signal to be measured at the sampling frequency and obtains a quantized time domain signal to be measured.
For example, when the main oscillation frequency of the motor device is changed from 1kHz to 1.2kHz or other frequencies other than 1kHz, the amplitude of the motor device must be changed after the amplitude calculation, and the results of the time domains to be measured are different. If the original first characteristic frequency disappears, the operation state is changed or the motor has abnormal condition.
Step S8, sampling the time domain signal to be measured according to the sampling start point and the target sampling frequency, and calculating the amplitude to be measured. The processing unit 11 finds a maximum value of at least one period of the quantized time-domain signal to be measured, and uses the maximum value as a sampling start point to be measured. The processing unit 11 sets a sampling frequency to be measured between more than one time of the characteristic frequency and the set sampling frequency from the maximum value, obtains a time domain result to be measured through the sampling frequency to be measured, and calculates an amplitude to be measured through the frequency result to be measured. The calculation method of the amplitude to be measured is the characteristic amplitude as described in the above steps S4 to S5.
Step S9, judging whether the amplitude to be measured is lower than the triggering amplitude, if yes, carrying out operation step S1 or triggering event; if not, the process proceeds to step S6.
Referring to fig. 6, the original time domain signal J to be measured is sampled by 12 kpsi, and the maximum value in N periods of the quantized time domain signal K to be measured is taken as the starting point of 2 kpsi sampling, where N is at least one period. In the region P, the 12kSPS sampling frequency is maintained until the 12kSPS sampling point is sampled to the next 2kSPS sampling point, and the sampling is switched to the 2kSPS sampling frequency completely. This operation can reduce it from a 12kSPS high frequency to a 2kSPS sampling frequency to achieve energy saving.
Please refer to fig. 7, which is a schematic diagram of waveforms from quantizing the time domain signal to determining whether the amplitude to be measured is lower than the trigger amplitude. The original time domain signal J to be measured (the top diagram in fig. 7) is sampled by 12kSPS, and the quantized time domain signal K to be measured is obtained (fig. 7 is from the top to fig. 2). And regarding the quantized time domain signal K to be detected, taking the maximum signal value of the quantized time domain signal K to be detected in N periods as a sampling starting point O to be detected, and sampling at the sampling frequency of 2kSPS to obtain the sampling waveform L of 2 kSPS. The phase of the sampling waveform L of the 2kSPS is 180 degrees, and then the sampling is carried out by using 1kSPS, so as to obtain the base line M of the sampling waveform L of the 2 kSPS. The sampled waveform L of 2kSPS and the base line M are further calculated as a superposed waveform N. The maximum amplitude of the superposed waveform N is the amplitude to be measured. If the amplitude to be measured is smaller than the trigger amplitude, performing step S1 or a trigger event; if the amplitude to be measured is not smaller than the trigger amplitude, step S6 is performed.
In summary, in the apparatus and method for detecting motor vibration or noise frequency according to the present invention, the processing unit 11 can calculate a time domain signal, calculate the time domain signal to obtain a frequency domain result, select a frequency with the maximum intensity of the frequency domain result as a characteristic frequency, set a target sampling frequency according to a sampling frequency that is one or more times the characteristic frequency, and switch from the set sampling frequency to the target sampling frequency for sampling operation in time domain signal sensing.
Claims (12)
1. A motor vibration or noise frequency detection device comprises:
a processing unit; and
the frequency sensing unit is electrically connected with the processing unit and at least provided with a vibration sensing module and a noise sensing module;
wherein the processing unit quantizes the time domain signal retrieved from the frequency sensing unit at the sampling frequency in step S1; in step S2, the quantized time domain signal is operated to obtain a frequency domain result; in step S3, a characteristic frequency is set according to the frequency domain result, and a target sampling frequency is set at least twice the characteristic frequency; in step S4, the maximum value of the time domain signal is taken as the starting point of sampling within N periods, where N is at least one period; in step S5, sampling the time domain signal according to the sampling start point and the target sampling frequency, calculating a characteristic amplitude, and setting a trigger amplitude according to the characteristic amplitude; in step S6, wait for a set delay time; in step S7, quantizing the time domain signal to be detected with the sampling frequency, and taking the maximum signal value as the start point of sampling to be detected within N periods of the time domain signal to be detected, where N is at least one period; in step S8, sampling the time domain signal to be measured according to the sampling start point and the target sampling frequency, and calculating a to-be-measured amplitude; and step S9, determining whether the amplitude to be measured is lower than the trigger amplitude, if so, performing step S1 or a trigger event, otherwise, performing step S6.
2. The apparatus according to claim 1, further comprising an energy management unit electrically connected to the frequency sensing unit and the processing unit.
3. The apparatus according to claim 1, further comprising an energy storage unit electrically connected to the energy management unit.
4. The apparatus according to claim 1, further comprising a wireless interface and an antenna unit, wherein the wireless interface is electrically connected to the processing unit, and the antenna unit is electrically connected to the wireless interface.
5. A method for detecting vibration or noise frequency of a motor includes the steps of:
step S1, quantizing the time domain signal with a first sampling frequency;
step S2, the quantized time domain signal is operated to obtain a frequency domain result;
step S3, setting a characteristic frequency according to the frequency domain result, and setting the frequency at least twice as high as the characteristic frequency as a target sampling frequency;
step S4, taking the maximum value of the time domain signal as the starting point of sampling within N periods, where N is at least one period;
step S5, sampling the time domain signal according to the sampling start point and the target sampling frequency, calculating a characteristic amplitude, and setting a trigger amplitude according to the characteristic amplitude;
step S6, waiting for a set delay time;
step S7, quantizing the time domain signal to be tested, taking the maximum value of the signal as the initial sampling point to be tested in the beginning N periods of the time domain signal to be tested, wherein N is at least one period;
step S8, sampling the time domain signal to be tested according to the sampling start point and the target sampling frequency, and calculating the amplitude to be tested;
step S9, judging whether the amplitude to be measured is lower than the triggering amplitude, if yes, executing the step S1 or triggering event; if not, the process proceeds to step S6.
6. The method according to claim 5, wherein in the step S1, the time domain signal is sampled by setting a sampling frequency and a sampling frequency, and a quantized time domain result is obtained.
7. The method of claim 5, wherein in step S2, the quantized time domain signal is transformed into the frequency domain result by Fourier transform.
8. The method of claim 5, wherein in step S3, the frequency with the maximum intensity of the frequency domain result is taken as the characteristic frequency.
9. The method according to claim 5, wherein in the step S4, a maximum value of at least one period of the quantized time domain signal is found and the maximum value is used as the sampling start point.
10. The method for detecting vibration or noise frequency of a motor according to claim 5, wherein the step S5 further comprises:
taking the sampling starting point as a starting point, and sampling the time domain signal at the target sampling frequency to obtain a sampling waveform;
sampling the sampled waveform 180 degrees in phase at a second sampling frequency to obtain a first baseline;
calculating the sampling waveform and the first baseline into a first superposed waveform, wherein the maximum amplitude value of the first superposed waveform is the characteristic amplitude; and
setting the characteristic amplitude value less than or equal to the trigger amplitude.
11. The method of claim 5, wherein in the step S7, the time-domain signal to be measured is sampled at the first sampling frequency to obtain a quantized time-domain signal to be measured.
12. The method according to claim 5, wherein the step S8 further comprises:
taking the sampling starting point to be detected as a sampling starting point and sampling at the target sampling frequency for the quantized time domain signal to be detected to obtain a sampling waveform to be detected;
sampling the sampling waveform to be measured by 180 degrees in phase, and sampling at a second sampling frequency to obtain a second baseline; and
and calculating the sampling waveform to be detected and the second baseline into a second superposed waveform, wherein the maximum amplitude of the second superposed waveform is the amplitude to be detected.
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| CN201811622528.7A CN111380607A (en) | 2018-12-28 | 2018-12-28 | Motor vibration or noise frequency detection device and method thereof |
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| CN201811622528.7A CN111380607A (en) | 2018-12-28 | 2018-12-28 | Motor vibration or noise frequency detection device and method thereof |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1111364A1 (en) * | 1999-12-23 | 2001-06-27 | Snecma Moteurs | Damage detection of motor pieces |
| KR20020074615A (en) * | 2001-03-21 | 2002-10-04 | 주식회사 캄코 | System and method for testing heating motor of vehicle |
| CN1688874A (en) * | 2002-08-30 | 2005-10-26 | 日本精工株式会社 | Method and device for monitoring status of mechanical equipment and abnormality diagnosing device |
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| CN108709635A (en) * | 2018-08-17 | 2018-10-26 | 国家电网有限公司 | Determine the method and device of characteristic of rotating machines vibration signal major frequency components information |
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2018
- 2018-12-28 CN CN201811622528.7A patent/CN111380607A/en not_active Withdrawn
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1111364A1 (en) * | 1999-12-23 | 2001-06-27 | Snecma Moteurs | Damage detection of motor pieces |
| KR20020074615A (en) * | 2001-03-21 | 2002-10-04 | 주식회사 캄코 | System and method for testing heating motor of vehicle |
| CN1688874A (en) * | 2002-08-30 | 2005-10-26 | 日本精工株式会社 | Method and device for monitoring status of mechanical equipment and abnormality diagnosing device |
| CN106556799A (en) * | 2015-09-30 | 2017-04-05 | 大亚湾核电运营管理有限责任公司 | A kind of On Fault Analysis of Generator and device |
| CN108709635A (en) * | 2018-08-17 | 2018-10-26 | 国家电网有限公司 | Determine the method and device of characteristic of rotating machines vibration signal major frequency components information |
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| Title |
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| 李绍江: "振动与噪声分析在航空发动机故障预警中的运用", 《科技创业家》 * |
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