JP2024022903A - Data collection device and data collection program for electric motor diagnosis - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data collection device that collects data for diagnosing an electric motor at any time and in an any operating state without using information such as model numbers and specifications.

SOLUTION: A data collection device 10 for diagnosing an electric motor 14 according to one embodiment comprises a sound acquisition unit 21, a characteristic acquisition unit 41, a data creation unit 42, and a storage unit 26. The sound acquisition unit 21 acquires sound generated from the electric motor 14. The characteristic acquisition unit 41 acquires the relation between a rotation speed of the electric motor 14 and a frequency of the sound acquired by the sound acquisition unit 21 as a sound characteristic. The data creation unit 42 creates reference data based on the relation between the rotation speed of the electric motor 14 and the frequency of the sound acquired by the sound acquisition unit 21 when the electric motor 14 is operated under a preset operating condition such that the rotation speed changes. The storage unit 26 stores the reference data created by the data creation unit 42.

SELECTED DRAWING: Figure 2

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present embodiment relates to a data collection device for diagnosing a motor based on the relationship between the rotation speed of the motor and the sound generated by the motor, and a data collection program that causes a mobile terminal to function as the data collection device.

Electric motors generate vibration and noise due to mechanical damage such as bearings, and electromagnetic noise due to electrical defects. The presence or absence of a malfunction in an electric motor is diagnosed based on these vibrations and noises. Conventionally, malfunctions of electric motors have been diagnosed using specifications based on the model number and by keeping the rotational speed constant.

However, it is necessary to obtain information such as the model number each time a motor is diagnosed, which hinders prompt diagnosis at any time. In addition, the bearings used in electric motors may be manufactured by different manufacturers than the electric motor, making it difficult to identify the model number and specifications, as well as requiring removal from the motor to determine the model number, making it difficult to obtain information. Sometimes it is difficult. Furthermore, in recent years, electric motors are often operated with variable rotational speeds, making diagnosis more complicated as it is necessary to control the rotational speed to a constant value. In addition, design information is also required for diagnosing electromagnetic noise generated by electric motors, and it is difficult for anyone other than the manufacturer to diagnose electric motors based on electromagnetic noise.

JP2020-85836A

Therefore, it is an object of the present invention to provide a data collection device that collects data for diagnosing a motor at any time and in any operating state without using information such as model number or specifications.
Another purpose is to provide a data collection program that allows a mobile terminal to collect data for diagnosing a motor at any time and in any operating state without using information such as model number or specifications. shall be.

A data collection device for diagnosing an electric motor according to one embodiment includes a sound acquisition section, a characteristic acquisition section, a data creation section, and a storage section. The sound acquisition unit acquires the sound generated from the electric motor. The characteristic acquisition section acquires, as a sound characteristic, the relationship between the rotation speed of the electric motor and the frequency of the sound acquired by the sound acquisition section. The data creation unit creates reference data based on the relationship between the rotation speed of the electric motor and the frequency of the sound acquired by the sound acquisition unit when the electric motor is operated under preset operating conditions such that the rotation speed changes. do. The storage unit stores the reference data created by the data creation unit.

A schematic diagram showing a schematic configuration of a data collection device for diagnosing an electric motor according to an embodiment A block diagram showing the configuration of a data collection device for diagnosing an electric motor according to an embodiment A schematic diagram showing changes in the sound generated by the motor and the effective value RMS as the rotation speed of the motor changes over time. Schematic diagram showing changes over time in each frequency band of sound generated by an electric motor Schematic diagram showing changes over time in representative values for each frequency band of sound generated by an electric motor Schematic diagram to explain the division of representative values of sound frequencies generated from electric motors Schematic diagram to explain the division of representative values of sound frequencies generated from electric motors Schematic diagram showing changes over time in representative values for each frequency band of sound generated by an electric motor A schematic diagram to explain the remarkable typical values found in the 0 to 1 kHz band of sound generated by electric motors. Schematic diagram to explain the remarkable typical values found in the 2-7kHz band of sound generated by electric motors Schematic diagram showing the flow of processing in a data collection device according to an embodiment Schematic diagram showing the configuration of reference data created by a data collection device according to an embodiment Schematic diagram showing the flow of processing in a data collection device according to an embodiment Schematic diagram showing the flow of processing in a data collection device according to an embodiment Schematic diagram showing the configuration of reference data created by a data collection device according to an embodiment

Hereinafter, one embodiment of a data collection device will be described based on the drawings.
1 and 2 are schematic diagrams showing the configuration of a data collection device 10 according to one embodiment. The data collection device 10 includes a mobile terminal 11. The mobile terminal 11 is called, for example, a so-called smartphone or a tablet. Further, the data collection device 10 may include a server device 12 in addition to the mobile terminal 11. The server device 12 is a device, such as an HDD, that has a storage area that can electromagnetically or optically store digital data. The mobile terminal 11 and the server device 12 are communicably connected via a communication network 13. The communication network 13 can be any communication network, such as a local area network (LAN), the Internet, a mobile phone communication network, or Ethernet.

The data collection device 10 is used by an operator (not shown) who diagnoses a target electric motor 14, as shown in FIG. The operator is, for example, a person who handles the electric motor 14, such as an owner of the electric motor 14 or a person in charge of maintenance, and a person who diagnoses the presence or absence of an abnormality. The mobile terminal 11 is carried by the operator when diagnosing the electric motor 14. The operator uses the mobile terminal 11 to collect sounds that serve as data for diagnosing the electric motor 14 .

The electric motor 14 has a stator 15 and a rotor 17 that rotates around a rotating shaft member 16. The rotor 17 is rotatably supported by a bearing member 18. The electric motor 14 is connected to a control device 19, and is driven by, for example, electric power output from an inverter (not shown) provided in the control device 19. The electric motor 14 is operated by the control device 19 according to operating conditions in which the rotation speed and the like are set in advance.

The mobile terminal 11 constituting the data collection device 10 includes a sound acquisition section 21, a display section 22, an input section 23, a communication section 24, and a control section 25, as shown in FIG. The sound acquisition unit 21 is a microphone, and is provided as an essential device in the mobile terminal 11. The sound acquisition unit 21 acquires sounds generated as the electric motor 14 operates. The display unit 22 is a display made of, for example, a liquid crystal or an organic LED, and is provided as an essential device in the mobile terminal 11. The input unit 23 is, for example, a touch panel configured integrally with the display unit 22, and is also provided as an essential device in the mobile terminal 11. The communication unit 24 is used to connect to the external communication network 13, and is provided as an essential device in the mobile terminal 11. The control unit 25 is composed of a microcomputer having a CPU, ROM, and RAM, and controls the entire mobile terminal 11 including the sound acquisition unit 21, the display unit 22, the input unit 23, and the communication unit 24. The data collection device 10 is realized in software by executing a data collection program on the mobile terminal 11.

The data collection device 10 includes a storage unit 26. The storage unit 26 may be provided in the mobile terminal 11 or may be provided in the external server device 12. In the case of this embodiment, the storage unit 26 includes a mobile storage unit 27 provided in the mobile terminal 11 and a main storage unit 28 provided in the server device 12. The portable storage unit 27 is composed of a storage medium such as a nonvolatile memory or a RAM, for example. The main storage unit 28 is preferably configured with a storage medium, such as an HDD, which is cheaper and has a larger capacity than memory. For example, a large amount of data is stored in the main storage unit 28 of the server device 12, and some data, such as data related to sound acquired from the electric motor 14 by the mobile terminal 11 and data used in diagnosing the electric motor 14, is stored in the main storage unit 28 of the server device 12. It may also be configured to be stored in the portable storage unit 27. In this way, the portable storage section 27 and the main storage section 28 can be used as desired depending on the purpose. The control unit 25 of the mobile terminal 11 controls the mobile storage unit 27.

The server device 12 includes a main storage section 28, a communication section 31, and a control section 32. The communication unit 31 is used to connect to the external communication network 13. Server device 12 communicates with mobile terminal 11 through communication unit 31 and communication network 13 . The control unit is composed of a microcomputer having a CPU, ROM, and RAM, and controls the entire server device 12 including the main storage unit 28 and the communication unit 31.

The data collection device 10 includes a characteristic acquisition section 41, a data creation section 42, a data update section 43, and a diagnosis determination section 44. These characteristic acquisition unit 41, data creation unit 42, data update unit 43, and diagnosis determination unit 44 are realized in software in the mobile terminal 11 by executing a computer program on the CPU of the control unit 25. The characteristic acquisition unit 41, data creation unit 42, data update unit 43, and diagnosis determination unit 44 are not limited to software, and may be realized by collaboration between software and hardware. When using the mobile terminal 11 as in the present embodiment, the CPU of the control unit 25 executes a data collection program that is a computer program, so that the mobile terminal 11 can be configured as follows: 43 and the diagnosis determination unit 44 are realized in software.

The characteristic acquisition unit 41 acquires sound characteristics. The sound characteristic is the relationship between the rotation speed of the electric motor 14 and the frequency of the sound acquired by the sound acquisition unit 21. The sound generated from the electric motor 14 differs depending on the rotation speed of the electric motor 14. That is, the sound generated from the electric motor 14 not only becomes louder as the rotation speed of the electric motor 14 increases, but also has a specific tendency in the frequency of the generated sound depending on the rotation speed. In order to grasp such a specific tendency, the characteristic acquisition unit 41 acquires the relationship between the rotation speed of the electric motor 14 and the frequency of the sound as a sound characteristic.

The data creation unit 42 creates reference data. The reference data are sound characteristics obtained when the electric motor 14 is operated under preset operating conditions. That is, the electric motor 14 is operated under preset operating conditions as a reference model. Then, the data creation unit 42 creates reference data using the sound characteristic that is the relationship between the rotational speed of the electric motor 14 and the frequency of the sound acquired by the sound acquisition unit 21 under this operating condition. The created reference data is stored in the storage unit 26.

After the reference data is created, the data update unit 43 creates update data for updating the reference data, and updates the reference data. The reference data is created using preset operating conditions as described above. On the other hand, the operating settings of the electric motor 14 may be changed, for example, due to continued use, the range of revolutions used may be expanded or parts may be replaced. When the settings are changed in this way, sound characteristics that cannot be obtained from the standard data may be required. Therefore, even after the reference data has been created, the data update section 43 creates update data using the sound characteristics acquired by the characteristic acquisition section 41, and replaces the standard data with the update data. In this case, the data update unit 43 may acquire the sound characteristics by operating the electric motor 14 with the same operation settings as when the reference data was created, or may operate the electric motor 14 with different settings than when the reference data was created. You may also drive the vehicle and obtain the sound characteristics.

The diagnosis determination unit 44 determines whether or not the electric motor 14 can be diagnosed, that is, whether or not the electric motor 14 can be diagnosed. As described above, the reference data or update data may not be available under all operating conditions of the electric motor 14. That is, the reference data or update data may not include reference data of a specific frequency band. As described above, when there is no reference data or updated data in a specific frequency band, diagnosis of the electric motor 14 cannot be performed. Therefore, the diagnosis determination unit 44 uses the reference data or update data stored in the storage unit 26 to determine whether or not the electric motor 14 can be diagnosed in the target frequency band.

The details of the processing by the data collection device 10 for the electric motor 14 will be described below.
(Creation of standard data)
The reference data is acquired by operating the electric motor 14 under preset operating conditions. As the preset operating conditions, for example, as shown in FIG. 3, a pattern of "start" - acceleration region - "rated rotational speed Rs" - deceleration region - "stop" is used. The electric motor 14 starts operating at time T0, reaches the rated rotation speed Rs at time T1, maintains the rated rotation speed Rs until time T2, and stops at time T3. That is, the electric motor 14 has an acceleration region from time T0 to time T1, a constant speed region from time T1 to time T2, and a deceleration region from time T2 to time T3. Here, the "rated rotation speed Rs" may be replaced with the "maximum rotation speed" expected for the rotation of the electric motor 14. Moreover, the above-mentioned operating conditions are just an example, and when a specific operating pattern is determined in advance for the electric motor 14, this specific operating pattern may be used as the operating condition. In this way, the operating conditions for obtaining the reference data can be set arbitrarily. In this embodiment, an example will be described in which the operation pattern of "start" - "rated rotation speed Rs" - "stop" is used as in the above example. FIG. 3 shows temporal changes in the rotational speed of the electric motor 14, temporal changes in the entire frequency band of the sound generated from the electric motor 14, and temporal changes in the root mean square value (RMS) based on this sound. It shows change.

When the electric motor 14 starts operating according to the operating conditions, the sound acquisition unit 21 acquires the sound generated from the electric motor 14. The sound acquisition unit 21 acquires the sound generated from the electric motor 14 using the microphone provided in the mobile terminal 11 as described above. The characteristic acquisition unit 41 acquires sound characteristics from the sound of the electric motor 14 acquired by the sound acquisition unit 21 and the rotation speed of the electric motor 14 . The rotation speed of the electric motor 14 corresponds to the elapsed time from time T0 when the electric motor 14 started operating. That is, the rotation speed of the electric motor 14 is controlled by the control device 19 based on operating conditions set in advance. Therefore, the rotation speed of the electric motor 14 is correlated to the elapsed time after the electric motor 14 is started. Thereby, the rotation speed of the electric motor 14 is specified according to the elapsed time from starting, without using a detection means such as a rotation speed sensor. Note that, of course, the rotation speed of the electric motor 14 may be detected using, for example, a sensor.

The characteristic acquisition unit 41 identifies a representative value of the vibration waveform for each rotation speed of the electric motor 14. Here, the representative value of the vibration waveform can be any numerical value, such as an effective value or an average value of absolute values, as long as it allows quantitative understanding of the magnitude of the waveform indicating the intensity of sound. The characteristic acquisition unit 41 analyzes the frequency for each rotation speed of the electric motor 14. Then, the characteristic acquisition unit 41 extracts the dominant component of the frequency that appears significantly at each rotation speed as a representative value. The extraction of representative values will be described in detail below.

The characteristic acquisition section 41 includes a plurality of frequency filters (not shown) that allow passage of sounds in a specific frequency band from among the sounds acquired by the sound acquisition section 21 . The characteristic acquisition unit 41 separates the sound acquired by the sound acquisition unit 21 into components of a plurality of frequency bands by passing the sound through these frequency filters. Specifically, the characteristic acquisition unit 41 sets an arbitrary set frequency range and separates sounds for each set frequency range. For example, when the frequency band to be analyzed is 0 to 10 kHz, the characteristic acquisition unit 41 determines the set frequency range, such as a frequency band of 0 to 1 kHz, a frequency band of 1 to 2 kHz, a frequency band of 9 to 10 kHz, etc. Set a range divided into 10. Then, the characteristic acquisition unit 41 creates a waveform that has been passed through a frequency filter for each set frequency range. At this time, the characteristic acquisition unit 41 creates a waveform correlated to the rotation speed of the electric motor 14 for each set frequency range. Further, the characteristic acquisition unit 41 identifies a representative value for each rotation speed from the waveform for each set frequency range. The representative value is specified as a numerical value that can be quantitatively grasped as described above, like the dominant component.

Here, the dominant component in the sound characteristics acquired by the characteristic acquisition section 41 is generated due to the following factors.
- Predominant component due to rotational imbalance This predominant component due to rotational imbalance is caused by rotational imbalance inherent in the rotor 17, etc., and is likely to occur at a relatively low rotation speed. This dominant component tends to occur in a critical rotational speed region unique to each rotor 17, such as when the electric motor 14 is in an acceleration region or a deceleration region. Furthermore, the dominant component that occurs at a relatively low rotational speed is also likely to occur if the electric motor 14 is improperly installed in the equipment. The dominant component due to this rotational imbalance tends to appear, for example, when the set frequency range is 0 to 1 kHz.

- Predominant component in the sliding part of the bearing member The predominant component in the sliding part of the bearing member 18 occurs in the sliding part between the rotor 17 and the bearing member 18 that supports it, and occurs during operation in a constant speed region. It's easy to do. This dominant component tends to occur due to the structure of the bearing member 18, such as wear of the bearing member 18 or lack of lubrication. Further, this dominant component is likely to occur due to the structural natural frequency of the electric motor 14. This dominant component tends to appear, for example, when the set frequency range is 2 to 8 kHz.

- Predominant component caused by the electromagnetic force and induced power of the motor The predominant component caused by the electric power of the motor 14 is caused by electromagnetic distortion, noise during energization, etc., and tends to occur in the entire rotation speed range. This dominant component tends to occur when the load on the electric motor 14 increases, for example, regardless of the rotation speed. This dominant component tends to appear, for example, when the set frequency range is 1 to 5 kHz.

In this way, the sound generated from the electric motor 14 has characteristics in its dominant components depending on the number of rotations, depending on the cause of the sound. Although these dominant components change depending on the rotational speed and load of the electric motor 14, they do not change significantly when there is no abnormality in the electric motor 14, that is, when there is no change in the mechanical condition of the electric motor 14. Therefore, the characteristic acquisition unit 41 acquires the sound generated from the motor 14 from startup through operation at the rated rotational speed until it stops according to the operating conditions, and extracts representative values that are dominant components at each rotational speed. do.

Prior to steady operation, the data creation unit 42 creates reference data using sound characteristics obtained from the electric motor 14 operated under specific preset operating conditions. The created reference data is stored in the storage unit 26.

Next, the sound generated by the electric motor 14 and its characteristics will be explained in detail.
(Sound made by electric motor)
From start to stop, the electric motor 14 includes an acceleration region, a constant speed region, and a deceleration region, as shown in FIG. The acceleration region is a region where the rotational speed of the electric motor 14 increases. The constant speed region is a region in which the electric motor 14 is operated at a preset constant rotation speed. The deceleration region is a region in which the rotational speed of the electric motor 14 decreases. In the acceleration region and the deceleration region, since the rotation speed of the electric motor 14 changes, the sound generated at the rotation speed specific to the electric motor 14 tends to become noticeable. This sound is caused by the imbalance of the components of the electric motor 14, as described above, and is generated at a specific rotation speed unique to the electric motor 14. On the other hand, in the acceleration region and the deceleration region, since the rotation speed of the electric motor 14 is low, it is difficult to detect sounds caused by the bearing member 18 and the like.

On the other hand, in the constant speed region, the number of rotations of the electric motor 14 is relatively high and maintained substantially constant, so the noise generated from the bearing member 18 tends to become noticeable. This sound is caused by an abnormality occurring in the bearing member 18 as described above, and is unrelated to changes in the rotational speed. On the other hand, in the constant speed region, since the rotational speed of the electric motor 14 is substantially constant, it is difficult to detect sounds caused by unbalance of the members of the electric motor 14.

(characteristics of sound)
In this embodiment, the sound generated from the electric motor 14 is acquired over time from the start of the electric motor until it stops after passing through a constant speed region, as shown in FIG. In the case of FIG. 3, the horizontal axis indicates the elapsed time since the electric motor 14 was started. The vertical axis indicates the rotation speed, sound intensity, and RMS effective value, respectively. Any sound intensity, such as Pa or dB, can be used as long as the absolute or relative sound intensity can be obtained. The characteristic acquisition unit 41 decomposes the sound of the electric motor 14 acquired from the sound acquisition unit 21 into a plurality of frequency bands by passing it through a frequency filter (not shown). For example, as shown in FIG. 4, the sound of the electric motor 14 is decomposed into a frequency band of 0 to 1 kHz, a frequency band of 1 to 2 kHz, and a frequency band of 2 to 8 kHz. Naturally, the frequency band may be decomposed into more regions.

The characteristic acquisition unit 41 acquires a representative value of each frequency band for each rotation speed of the electric motor 14. As mentioned above, the rotation speed of the electric motor 14 is specified by the elapsed time after starting. Then, the characteristic acquisition unit 41 acquires a representative value at a specific rotation speed of the electric motor 14 for each frequency band. The representative value is a numerical value that allows quantitative understanding of the magnitude of the vibration waveform, such as an effective value or an average value of absolute values, as described above.

For example, if the sound of the electric motor 14 is acquired in the range of 0 to 10 kHz and divided into 10 set frequency bands: 0 to 1 kHz, 1 to 2 kHz, 2 to 3 kHz, ... 9 to 10 kHz, the elapsed time, that is, the rotation The representative value for each number is obtained as shown in FIG. It can be seen from FIG. 5 that the representative value for each rotation speed has characteristics for each frequency band.

The set frequency range can be set arbitrarily as described above. FIGS. 6 and 7 show the relationship between frequency and intensity of sound acquired at a specific rotation speed. The set frequency range can be set to two regions, 0 to 1 kHz and 3 to 8 kHz, as shown in FIG. 6, or ten regions of 1 kHz each, as shown in FIG. 7, for example. Alternatively, the set frequency range may be set to three regions, 0 to 1 kHz, 2 to 3 kHz, and 7 to 8 kHz, as shown in FIG. Among these, the set frequency range of 0 to 1 kHz is a region where changes in sound due to imbalance of members such as rotational imbalance are likely to occur. The set frequency range of 2 to 3 kHz is a region where changes in electromagnetic sound such as electromagnetic distortion and noise during energization are likely to appear. The set frequency range of 7 to 8 kHz is a region where changes in sound due to mechanical damage such as damage to the bearing member 18 are likely to occur. In this way, the number of set frequency ranges is arbitrarily set depending on, for example, the capacity of the storage unit 26 and the processing capacity of the mobile terminal 11.

Next, the criteria for diagnosing the electric motor 14 using reference data will be explained.
The sound characteristics created with the set frequency range from 0 to 1 kHz have a relationship between the elapsed time as the number of rotations and the sound intensity as shown in FIG. 9. The sound characteristics in this set frequency range include regions where the sound intensity increases significantly at A1 and A2 in FIG. A1 is a value that appears when the rotation speed of the electric motor 14 increases in the acceleration region, and A2 is a value that appears when the rotation speed decreases in the deceleration region. The remarkable value that appears in A1 or A2 is caused by the progression of unbalance of the electric motor 14 or poor installation of the electric motor 14. Therefore, by using the sound characteristics in the set frequency range of 0 to 1 kHz included in the reference data, it is possible to diagnose progress of unbalance or poor installation as the cause of the abnormality occurring in the electric motor 14.

Further, the sound characteristics created with the set frequency range of 2 to 7 kHz have a relationship between the elapsed time as the number of rotations and the sound intensity as shown in FIG. 10. The sound characteristics in this set frequency range include a region where the sound intensity increases significantly at A3 in FIG. A3 is a value that appears when the rotational speed of the electric motor 14 is approximately constant in the constant speed region. The remarkable value that appears in A3 is mainly caused by an abnormality in the bearing member 18. Therefore, by using the sound characteristics in the set frequency range of 2 to 7 kHz included in the reference data, it is possible to diagnose an abnormality in the bearing member 18 as the cause of the abnormality occurring in the electric motor 14.

In this way, after acquiring the reference data, the sound generated by the electric motor 14 during normal operation is acquired. By comparing the sound characteristics of the acquired sound with reference data, the presence or absence of an abnormality in the electric motor 14 and the cause of the abnormality are diagnosed.

The flow of processing of the data collection device with the above configuration will be explained.
(Standard data creation process)
Prior to diagnosing the electric motor 14, reference data is created according to the flow shown in FIG. When the reference data creation process is started, the sound acquisition unit 21 acquires the sound of the electric motor 14 in all rotation speed regions (S101). The electric motor 14 is operated according to preset operating conditions. At this time, the operating conditions for the electric motor 14 are set to, for example, a series of operations from starting to reaching the rated rotational speed to stopping as described above. The operating conditions are not limited to the period from starting to the rated rotational speed to stopping, but can be arbitrarily set such as a specific rotational speed range in which the electric motor 14 is operated. The electric motor 14 is started by the control device 19, and then goes through an acceleration region, a constant speed region, and a deceleration region over time, and then stops. Thereby, in the electric motor 14, the elapsed time after starting and the rotation speed are correlated.

The characteristic acquisition unit 41 processes the sound acquired by the sound acquisition unit 21 with a filter (S102). That is, the characteristic acquisition unit 41 separates the sound of the electric motor 14 acquired by the sound acquisition unit 21 into arbitrary set frequency ranges. The waveform of this separated sound is obtained as an intensity corresponding to the elapsed time from the start of the electric motor 14, as shown in FIG. 4 and the like. The characteristic acquisition unit 41 acquires a representative value for each rotation speed of the electric motor 14 in the plurality of set frequency ranges obtained (S103). At this time, the characteristic acquisition unit 41 acquires representative values for all rotational speeds of the electric motor 14. That is, the characteristic acquisition unit 41 acquires a representative value for each of a plurality of set frequencies and for each rotation speed of the electric motor 14. Thereby, for example, as shown in FIG. 5, a representative value of the frequency with respect to the elapsed time, that is, the rotational speed of the electric motor 14 is obtained for each set frequency range.

The data creation unit 42 creates reference data (S104). The reference data is created, for example, as a database showing the relationship between the rotation speed of the electric motor 14 and the representative value for each frequency band, as shown in FIG. The created reference data is stored in the storage unit 26 (S105).

(Diagnostic data creation process 1)
The flow of the diagnostic data creation process 1 for the electric motor 14 will be explained based on FIG. 13. The diagnostic data creation process 1 for diagnosing the electric motor 14 is similar to the reference data creation process described above. Therefore, the outline will be explained. However, during the diagnostic data creation process 1, the electric motor 14 is not necessarily operated under the same settings as the preset operating conditions.
The sound acquisition unit 21 acquires the sound of the electric motor 14 in all rotation speed regions (S201). At this time, the electric motor 14 is operated according to arbitrary settings. The settings for operating the electric motor 14 may be the same settings as in the reference data creation process, or may be different settings. In this case as well, the operation of the electric motor 14 is controlled by the control device 19.

The characteristic acquisition unit 41 processes the sound acquired by the sound acquisition unit 21 with a filter (S202). That is, the characteristic acquisition unit 41 separates the sound of the electric motor 14 acquired by the sound acquisition unit 21 into arbitrary set frequency ranges. Then, the characteristic acquisition unit 41 acquires a representative value for each rotation speed of the electric motor 14 in the plurality of set frequency ranges obtained (S203). At this time, the characteristic acquisition unit 41 acquires representative values for all rotational speeds of the electric motor 14. That is, the characteristic acquisition unit 41 acquires a representative value for each of a plurality of set frequencies and for each rotation speed of the electric motor 14.

The data creation unit 42 creates diagnostic data (S204). Similar to the reference data, the diagnostic data is created as a database showing the relationship between the rotation speed and the representative value for each frequency band, as shown in FIG. 11, for example. The created diagnostic data is stored in the storage unit 26 (S205).

(Diagnostic data creation process 2)
The flow of the diagnostic data creation process 2 for the electric motor 14 will be explained based on FIG. 14. This diagnostic data creation process 2 differs from the above-described reference data creation process and diagnostic data creation process 1 in that the sound of the electric motor 14 is acquired only at a specific rotation speed.
When the electric motor 14 is in a steady operating state, the number of revolutions may be maintained constant, or the number of revolutions may be maintained such that fluctuations in the number of revolutions are small. That is, the electric motor 14 may be operated only within a specific rotation speed range, unlike the preset operating conditions. In such a case, the characteristic acquisition unit 41 may not be able to measure the sound at all rotational speeds of the electric motor 14 during steady operation of the electric motor 14, which is the same as when creating the reference data. On the other hand, data for diagnosing the electric motor 14 does not necessarily need to be acquired at all rotational speeds of the electric motor 14, and even at a specific rotational speed, data for diagnosing the electric motor 14 only at that rotational speed may be acquired. good. Therefore, in the diagnostic data creation process 2, an example will be described in which the sound of the electric motor 14 is acquired only at a specific rotation speed.

The sound acquisition unit 21 acquires the sound of the electric motor 14 in a specific rotation speed range (S301). When the electric motor 14 is in a normal operating state, it may be operated only within a specific rotational speed range without necessarily accelerating or decelerating from start to stop. In this manner, when the setting is for normal operation, diagnosis of the electric motor 14 is performed based on the rotation speed at this setting. Therefore, in the diagnostic data creation process 2, sounds for diagnosing the electric motor 14 are acquired in a limited rotational speed range with specific settings.

The characteristic acquisition unit 41 processes the sound acquired by the sound acquisition unit 21 with a filter (S302). That is, the characteristic acquisition section 41 separates the sound of the electric motor acquired by the sound acquisition section 21 into arbitrary set frequency ranges. Then, the characteristic acquisition unit 41 acquires a representative value at a specific rotation speed of the electric motor 14 in the plurality of set frequency ranges obtained (S303). That is, the characteristic acquisition unit 41 acquires a representative value for each set frequency at a specific rotation speed of the electric motor 14.

The data creation unit 42 creates diagnostic data (S304). The diagnostic data is created as a database of representative values for each frequency band at a specific rotation speed, as shown in FIG. 15, for example. The created diagnostic data is stored in the storage unit 26 (S305).

Incidentally, after the electric motor 14 is installed in equipment, the operating rotation speed and structure may change due to, for example, a change in specifications. In such a case, the data update unit 43 updates the reference data and creates updated data based on the operation of the electric motor 14 after the specifications have been changed. When the specification of the electric motor 14 is changed, for example, as shown in FIG. 15, if there is an area in which the representative value is not acquired in the database serving as the reference data, the data updating unit 43 updates the database based on the sound characteristics acquired in the latest operation. The representative value corresponding to the blank field is extracted, the reference data database is updated, and the data is updated. Thereby, the data update unit 43 creates a database of the latest update data for diagnosing the electric motor 14.

Further, the diagnosis determination unit 44 determines whether or not the electric motor 14 can be diagnosed, that is, whether or not the electric motor 14 can be diagnosed. As shown in FIG. 15 described above, the reference data may not be available under all operating conditions of the electric motor 14. In this way, when there is no reference data in a specific frequency band, it may not be possible to diagnose the electric motor 14. Therefore, the diagnosis determining unit 44 uses the reference data stored in the storage unit 26, that is, the reference data updated by the update data, to determine whether or not it is possible to diagnose the electric motor 14 in the target frequency band. .

Through the above-described procedure, the data collection device 10 creates reference data, update data, and diagnostic data for diagnosing the electric motor 14. A diagnosing person who diagnoses the electric motor 14 diagnoses the electric motor 14 using reference data or update data stored in the storage unit 26 and diagnostic data based on the latest sound acquired from the electric motor 14 using the mobile terminal 11. . That is, the diagnostician compares the latest diagnostic data with the reference data or updated data. Then, the diagnostician diagnoses whether there is an abnormality in the electric motor 14 based on the sound characteristics of the electric motor 14 obtained as the latest diagnostic data, and identifies the location where the abnormality is occurring. The specific procedure for diagnosing the electric motor 14 by the diagnostician can be set arbitrarily.

In the embodiment described above, the sound characteristics of the electric motor 14 are acquired using the mobile terminal 11. The operator can determine whether or not there is an abnormality in the motor 14 by comparing the reference data or updated data, which is the sound characteristics of the motor 14 obtained under preset operating conditions, with the latest diagnostic data obtained from the motor 14. Diagnose the cause. That is, in one embodiment, the relationship between the rotational speed of the electric motor 14 and the frequency of the generated sound is acquired as reference data by driving under specific operating conditions. Therefore, data for diagnosing the electric motor 14 at any time and in any operating state can be collected without using information such as the model number and specifications of the electric motor 14. Then, the operator can compare the diagnostic data acquired at any time and in any operating state with the reference data and update data acquired in advance, without using information such as the model number and specifications of the electric motor 14. The electric motor 14 can be diagnosed.

Additionally, in one embodiment, reference data is obtained and stored as a database. As a result, reference data and update data that serve as a basis for diagnosing the electric motor 14 are obtained regardless of the specifications of the electric motor 14 and the bearing member 18 constituting the electric motor 14 or the operating state of the electric motor 14. In other words, when collecting diagnostic data, the electric motor 14 does not require changing operating conditions such as stopping or changing the rotation speed, or disassembling the electric motor 14. Therefore, data for diagnosing the electric motor 14 can be easily collected no matter what operating state the electric motor 14 is in.

Although multiple embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included within the scope and gist of the invention, as well as within the scope of the invention described in the claims and its equivalents.

In the drawing, 10 is a data collection device, 11 is a mobile terminal, 14 is an electric motor, 21 is a sound acquisition unit, 26 is a storage unit, 41 is a characteristic acquisition unit, 42 is a data creation unit, 43 is a data update unit, and 44 is a diagnosis The determination section is shown.

Claims (8)

a sound acquisition unit that acquires sound generated from the electric motor;
a characteristic acquisition unit that acquires the relationship between the rotation speed of the electric motor and the frequency of the sound acquired by the sound acquisition unit as a sound characteristic;
a data creation unit that creates reference data from the relationship between the rotation speed of the electric motor and the frequency of the sound acquired by the sound acquisition unit when the electric motor is operated under preset operating conditions such that the rotation speed changes; ,
a storage unit that stores the reference data created by the data creation unit;
A data collection device for diagnosing an electric motor. The data creation unit sets two or more preset arbitrary frequency ranges for sounds generated from the electric motor as set frequency ranges, and calculates a representative value corresponding to the rotation speed of the electric motor for each set frequency range. The data collection device according to claim 1, wherein the data collection device sets: Claim further comprising: a data updating unit that operates the electric motor under conditions that are the same as or different from the operating conditions after creating the reference data, and updates the reference data using the sound characteristics acquired by the characteristic acquisition unit. 2. The data collection device according to 1 or 2. 4. The data collection device according to claim 3, further comprising a diagnosis determination unit that determines whether or not the electric motor can be diagnosed, depending on the sound characteristics included in the reference data. A computer program for causing a mobile terminal to function as a data collection device that collects data used for diagnosing an electric motor, the computer program comprising:
a sound acquisition procedure in which a sound acquisition unit acquires the sound generated from the electric motor according to changes in rotation speed;
a data creation step of creating reference data from the relationship between the rotational speed of the motor acquired in the sound acquisition step and the frequency of the sound acquired by the sound acquisition unit when the electric motor is operated under preset operating conditions;
a storage step of storing the reference data created in the data creation step in a storage unit;
A data collection program that runs In the data creation procedure, two or more arbitrary frequency ranges set in advance for the sound generated by the electric motor are set as set frequency ranges, and a representative value corresponding to the rotation speed of the electric motor is determined for each set frequency range. 6. The data collection program according to claim 5. After creating the reference data, when the electric motor is operated under the same or different conditions as the operating conditions,
7. The data collection program according to claim 5, further causing an update data creation step to create update data by updating the reference data using the sound characteristics acquired in the sound acquisition step. 8. The data collection program according to claim 7, further causing a diagnostic determination procedure to determine whether or not the electric motor can be diagnosed in accordance with the sound characteristics included in the reference data.

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