JP2023089923A - Abnormality detection system - Google Patents

Abstract

To provide an abnormality detection system for a facility apparatus, which is, with a simple configuration without using any sensor that requires power supply, capable of accurately detecting an abnormality in the facility apparatus.SOLUTION: An abnormality detection system 1 includes a facility apparatus-side device 2 and an abnormality detection device 3. The facility apparatus-side device 2 includes: a vibration power generation sensor 21 that is set so that its resonance frequency is a frequency of vibration generated when a facility apparatus operates normally, and that generates power by vibrations generated by the facility apparatus; and a transmitting unit 25 that, each time an amount of power obtained by the vibration power generation sensor 21 reaches a power threshold, consumes the amount of power and transmits a signal. The abnormality detection device 3 includes a receiving unit 31 that receives the signal, and a diagnosis unit 34 that diagnoses whether or not an operating state of the facility apparatus is abnormal based on a time interval of receiving the signal.SELECTED DRAWING: Figure 2

Description

The present invention relates to an anomaly detection system for detecting anomalies in equipment.

Conventionally, it is possible to detect abnormalities in equipment by acquiring the status of equipment in operation from sensors attached to equipment, etc., and transmitting this to an information processing device, etc. for analysis. It is done.
For example, Patent Literature 1 discloses a sensor installed at a desired portion of a bogie of a railway vehicle, a communication unit that communicates a signal output from the sensor, and a determination unit that determines the signal communicated from the communication unit. A truck health monitoring system is disclosed. In the bogie health monitoring device, a long plate having a piezoelectric element is supported so as to allow deflection in a direction perpendicular to the plate surface of the plate. A vibration power generator is provided to generate power. The vibration power generator supplies power to a sensor provided on the railroad vehicle.
In addition, Patent Document 2 discloses a sensor that detects an abnormality in a belt conveyor, a data transmission unit that transmits data acquired by the sensor, and a sensor that generates power by vibration of the belt conveyor and acquires data by the sensor and transmits data. and a vibration power generator that provides power for the .
The configurations disclosed in Patent Documents 1 and 2 require sensors for detecting abnormalities, a data transmission section for transmitting signals detected by the sensors, and a vibration power generation device for supplying power to them. , the number of parts increases.

On the other hand, in Patent Document 3, a plurality of vibration power generators are arranged on the outer peripheral surface of a bearing device that rotatably supports a main shaft, and each of these plurality of vibration power generators generates vibration generated when the main shaft rotates. A configuration is disclosed in which power is generated, power generation amount information is transmitted to a processing device, and the processing device detects rotational runout of the main shaft based on the difference in the power generation amounts of the plurality of vibration power generation devices.
In such a configuration, since an abnormality is detected based on the power generation amount of the vibration power generator, a sensor for acquiring the state of the bearing device is not particularly required, but a plurality of vibration power generators are required. , the number of parts still increases.
It is desired to accurately detect an abnormality in equipment with a simple configuration without using a sensor that requires a power supply.

JP 2015-204713 A JP-A-2021-1075 JP 2018-136863 A

The problem to be solved by the present invention is to provide an abnormality detection system for facility equipment that does not use a sensor that requires power supply and that can accurately detect an abnormality in facility equipment with a simple configuration.

As an anomaly detection system for detecting anomalies in facility equipment, the present inventors attached a vibration power generation sensor that generates power by vibration to the equipment without installing an acceleration sensor or the like in the equipment, and obtained by the vibration power generation sensor. and an anomaly detection device that diagnoses that the equipment is operating abnormally based on the power generation information (power amount, time information) that is received. The present invention has been achieved by paying attention to the point that it is possible.
In order to solve the above problems, the present invention employs the following means.
That is, the anomaly detection system of the present invention is an anomaly detection system for detecting an anomaly in equipment, and includes an equipment-side device attached to the equipment and an anomaly detection device, wherein the equipment-side device is , the resonance frequency is set to be the frequency of vibration when the equipment operates normally, a vibration power generation sensor that generates power by the vibration generated by the equipment, and the amount of electric power obtained by the vibration power generation sensor is and a transmitting unit that consumes the power amount and transmits a signal each time the power threshold is reached, and the anomaly detection device includes a receiving unit that receives the signal and a time interval for receiving the signal. and a diagnostic unit for diagnosing whether or not the operating state of the equipment is abnormal.
According to such a configuration, the vibration power generation sensor generates power by vibration generated by the equipment. When the amount of power obtained by the vibration power generation sensor reaches the power threshold, the device on the facility equipment side transmits a signal from the transmitter. Since the amount of electric power obtained by the vibration power generation sensor is consumed by transmitting the signal from the transmission unit, the facility equipment side device receives the power newly obtained by the vibration power generation sensor after the power amount is consumed. When the amount of power is stored and reaches the power threshold again, the transmitter transmits a signal. Thus, the signal is repeatedly transmitted at time intervals.
Further, the resonance frequency of the vibration power generation sensor is set to be the frequency of vibration when the equipment operates normally. Therefore, when the equipment is operating normally, the vibration power generation sensor resonates with the vibration of the equipment, increasing the amount of power generation. When equipment is not operating normally and the frequency of vibration emitted by the equipment increases or decreases compared to when it is operating normally and deviates from the resonance frequency of the vibration power generation sensor, the vibration power generation sensor Vibration in is suppressed, and the amount of power generation is reduced. In addition, when the equipment is not operating normally and the amplitude of the vibration generated by the equipment increases compared to when it is operating normally, the amount of power generated by the vibration power generation sensor increases and the amplitude decreases. In this case, the amount of power generated is reduced. In either case, as a result, when the equipment is not working normally, the amount of power generation is greater or less than when the equipment is working normally.
Here, if the amount of power generated by the vibration power generation sensor is large, the amount of power obtained by the vibration power generation sensor reaches the power threshold more quickly, so the time interval at which the transmission unit transmits the signal becomes shorter. Conversely, if the amount of power generated by the vibration power generation sensor is small, the time interval at which the signal is transmitted by the transmitter increases. That is, when the equipment is not operating normally, the time interval at which the signal is received by the receiving unit is longer or shorter than when the equipment is operating normally. Based on this time interval, the diagnosis unit of the abnormality detection device diagnoses whether or not the operating state of the equipment is abnormal.
In this way, in the above configuration, if there is a large difference in either the frequency or the amplitude of the vibration generated by the equipment when the equipment is operating normally, Since it can be determined that the operating state is abnormal, it is possible to accurately detect the abnormality of the equipment.
In addition, basically one vibration power generation sensor is required for detecting an abnormality in equipment as described above. In addition to the vibration power generation sensor, no other type of sensor is particularly required. Therefore, the configuration can be simplified.
In this way, it is possible to provide an abnormality detection system for facility equipment that is capable of accurately detecting an abnormality in facility equipment with a simple configuration without using a sensor that requires power supply.

In one aspect of the present invention, the time interval when the equipment operates normally is assumed to have a normal distribution, and the lower threshold is set by subtracting a value based on the standard deviation from the average value of the normal distribution. and an upper threshold value is set by adding the value based on the standard deviation to the average value, and the diagnostic unit determines whether the time interval for receiving the signal is smaller than the lower threshold value or the upper threshold value is If it is larger than the threshold, it is diagnosed that the operating state of the equipment is abnormal.
As described above, the diagnostic unit of the anomaly detection device determines the time interval at which a signal is transmitted from the vibration power generation device each time the amount of power obtained by the vibration power generation sensor reaches the power threshold. It is used as a criterion for diagnosing whether or not
Here, according to the above configuration, the time interval at which the signal is received by the receiving unit when the equipment is operating normally is regarded as a normal distribution, and based on the average value and standard deviation of the normal distribution, A lower threshold value and an upper threshold value are set, and the diagnosis unit diagnoses that the operating state of the equipment is abnormal when the time interval for receiving the signal is smaller than the lower threshold value or larger than the upper threshold value. As a result, even if there is variation (fluctuation) in the vibration state in the operating state of the equipment, it is possible to accurately detect an abnormality in the equipment.

In one aspect of the present invention, the diagnosis unit determines the difference obtained by subtracting the average value of the time intervals when the equipment is operating normally from the time interval for receiving the signal, and determines whether the equipment is normal. Calculate the absolute value of the cumulative value within a certain time of the deviation value obtained by dividing by the standard deviation of the time interval when the equipment operates normally, and calculate the absolute value of the cumulative value. When the deviation value of the cumulative value obtained by dividing the actual cumulative value by the standard deviation of the absolute value of the cumulative value is larger than the judgment threshold value, it is diagnosed that the operating state of the equipment is abnormal.
For example, in the case where equipment is partially damaged and strong and very short whisker-like pulse-like vibrations occur periodically, the amount of power generated by the vibration power generation sensor is similarly strong and short. A power waveform having a pulse-like component is obtained. In this case, the increase in amplitude due to the pulse-like component occurs within a short period of time, so although the amount of power generated by the vibration power generation sensor increases, the amount of increase is very small. Therefore, the time interval at which the transmission unit of the equipment device transmits a signal is slightly shorter than when the equipment operates normally. In this way, when there is a slight difference in the time interval between when the equipment operates normally and when an abnormality occurs, the diagnostic unit determines whether the equipment can Even if you try to diagnose whether the operating state of is abnormal, there is a possibility that the diagnosis cannot be performed correctly.
Here, by dividing the difference obtained by subtracting the average value of the time interval when the equipment is operating normally from the time interval for receiving the signal by the standard deviation of the time interval when the equipment is operating normally Consider calculating the deviation value. Such a deviation value tends to be a value close to 0 when the equipment is operating normally. Since the time interval is slightly shorter than the time interval when the equipment operates normally, it tends to be a negative value that is slightly smaller than the value when the equipment operates normally. The deviation value calculated in this way is a value that does not change greatly from 0 in the normal state even if a pulse-like vibration occurs. I don't get it. However, when pulse-like vibration occurs periodically, if the cumulative value of the deviation value is calculated within a certain time range, the difference from the normal value is accumulated, and the normal time should be a value that reflects the difference from the value of
Based on this idea, in the configuration described above, the absolute value of the accumulated deviation value is used to diagnose whether or not the equipment is operating abnormally. In particular, in order to perform diagnosis more accurately, the diagnosis unit divides the absolute value of the cumulative value by the standard deviation of the absolute value of the cumulative value when the equipment is operating normally, thereby obtaining the deviation value of the cumulative value to calculate The deviation value of the cumulative value calculated in this way is compared with the determination threshold value, and if the deviation value of the cumulative value is larger than the determination threshold value, it is diagnosed that the operating state of the equipment is abnormal. As a result, even when an abnormality occurs in which the amount of power generated by the vibration power generation sensor is only slightly different from when the equipment is operating normally, it is possible to accurately detect an abnormality in the equipment. .

In one aspect of the present invention, the vibration power generation sensor includes a base that receives vibrations generated by the equipment, a weight connected to the base via a connection shaft, and a weight connected to the base at a position spaced apart from the connection shaft. and a connected piezoelectric element, and when the equipment vibrates, the weight vibrates, and pressure acts on the piezoelectric element due to resonance, whereby the piezoelectric element generates power.
According to such a configuration, when the facility equipment vibrates, the base of the vibration power generation sensor receives the vibration generated by the facility equipment. Then, the base vibrates together with the equipment, and the weight connected to the base via the connection shaft vibrates. Due to the resonance with the vibration of the weight, pressure acts on the piezoelectric element and electric power is generated in the piezoelectric element. By using the vibration power generation sensor having such a configuration, an abnormality detection system can be appropriately realized.

ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the abnormality detection system of equipment which can detect the abnormality of equipment with a simple structure accurately, without using the sensor which needs power supply.

It is a figure showing a schematic structure of an anomaly detection system concerning a 1st embodiment of the present invention. 2 is a block diagram showing the functional configuration of the anomaly detection system of FIG. 1; FIG. FIG. 3 is a diagram showing the configuration of a vibration power generation sensor provided in the equipment side device of the abnormality detection system of FIG. 2 ; FIG. 4 is a diagram showing the correlation between the resonance frequency and the power generation amount in the vibration power generation sensor; FIG. 4 is a diagram showing an example of changes in the amount of electricity stored in a power storage unit; FIG. 5 is a diagram showing the power generation amount in the vibration power generation sensor that changes depending on the operating state of equipment. FIG. 5 is a diagram showing changes in the amount of electricity stored in an electricity storage unit when equipment is operating normally; FIG. 5 is a diagram showing changes in the amount of electricity stored in the electricity storage unit when the amplitude of vibration of the equipment increases. FIG. 10 is a diagram showing changes in the amount of electricity stored in the power storage unit when the frequency of vibration of equipment changes or when the amplitude of vibration decreases. FIG. 5 is a diagram showing changes in the amount of power generated by a vibration power generation sensor and changes in the amount of electricity stored in a power storage unit in actual equipment according to the operating state of the equipment. 4 is a flow chart showing the flow of an anomaly detection method in the anomaly detection system according to the first embodiment of the present invention; FIG. 10 is a diagram showing changes in the amount of power generated by a vibration power generation sensor when an abnormality occurs in equipment that is operating normally at a certain point in time. 13 is a diagram showing changes in the amount of electricity stored in the electricity storage unit in the case of FIG. 12; FIG. FIG. 13 is a diagram showing changes in the case of FIG. 12 of the deviation value and the absolute value of the cumulative value used in the anomaly detection system according to the second embodiment of the present invention; 9 is a flow chart showing the flow of an anomaly detection method in an anomaly detection system according to a second embodiment of the present invention; FIG. 10 is a diagram showing a modification of the vibration power generation sensor in the anomaly detection system of the present invention; FIG. 10 is a diagram showing a modification of the vibration power generation sensor in the anomaly detection system of the present invention;

The present invention is an anomaly detection system for facility equipment that detects an anomaly in the equipment, including an equipment-side device attached to the equipment and an anomaly detection device. The facility device side device includes a vibration power generation sensor that generates power by vibration generated by the facility device, and a transmitter that transmits a signal each time the amount of power obtained by the vibration power generation sensor reaches a power threshold. Further, the abnormality detection device includes a diagnosis unit that diagnoses whether or not the operating state of the facility equipment is abnormal based on the time interval at which the signal is received.
DESCRIPTION OF THE PREFERRED EMBODIMENTS A mode for carrying out an anomaly detection system according to the present invention will be described below with reference to the accompanying drawings.

[First embodiment]
FIG. 1 shows a schematic configuration of an anomaly detection system according to a first embodiment of the present invention. FIG. 2 is a block diagram showing the functional configuration of the anomaly detection system of FIG.
As shown in FIG. 1, the anomaly detection system 1 includes an equipment-side device 2 attached to equipment 100 that generates vibration to be monitored, and an anomaly detection device 3 . The anomaly detection system 1 detects an anomaly of the equipment 100 .
In this embodiment, the equipment 100 includes a rotating body, such as a circulator for circulating indoor air, which is supported by bearings and always rotates at a constant speed. The equipment 100 is not limited to this, and may be anything as long as it has a drive system that always operates at a constant speed and in a constant state.
As shown in FIG. 2 , the equipment device 2 includes a vibration power generation sensor 21 , a power storage unit 22 , a control unit 23 , a time acquisition unit 24 and a transmission unit 25 .

FIG. 3 is a diagram showing the configuration of a vibration power generation sensor provided in the equipment side device of the anomaly detection system of FIG. 2 .
As shown in FIG. 3, the vibration power generation sensor 21 is attached to a predetermined portion of the equipment 100 where the vibration generation state should be monitored. The vibration power generation sensor 21 generates power by vibration generated by the equipment 100 . When the vibration power generation sensor 21 receives the vibration of the equipment 100, the vibration energy is converted into electrical energy and output. The vibration power generation sensor 21 includes a base 211 , a vibrator 210 and a piezoelectric element 214 .
The base 211 is fixed to a predetermined portion of the equipment 100 . The base 211 is plate-shaped, for example, and is fixed along the surface 100f of a predetermined portion of the equipment 100 by welding, adhesion, bolting, or the like. The base 211 receives vibrations generated by the equipment 100 .
The vibrator 210 has a connection shaft 212 and a weight 213 . The connection shaft 212 connects the base 211 and the weight 213 . The connecting axis 212 extends in a direction perpendicular to the surface 100f. The connection shaft 212 is, for example, strip-shaped or rod-shaped. The weight 213 is provided at the tip of the connection shaft 212 . When the equipment 100 vibrates, the weight 213 causes the connection shaft 212 to oscillate around the base end portion of the base portion 211 side of the vibrator 210 with the weight 213 . It deforms elastically. The mass of the weight 213 constituting the vibrator 210, the length of the connection shaft 212, the rigidity, etc. are set so that the weight 213 vibrates when the equipment 100 vibrates. Here, the vibrator 210 is set so that its resonance frequency is the frequency of vibration when the equipment 100 operates normally.
The piezoelectric element 214 is arranged at a position spaced apart from the connection shaft 212 . For example, a piezoelectric element or the like can be used as the piezoelectric element 214 . The piezoelectric element 214 is spaced apart from the connecting shaft 212 in a direction intersecting the extending direction of the connecting shaft 212 . In this embodiment, a pair of piezoelectric elements 214 are arranged on both sides in a direction intersecting the direction in which the connecting shaft 212 extends. Each piezoelectric element 214 is connected to the base 211 via a support member 215 . Support member 215 extends parallel to connecting shaft 212 from base 211 . The piezoelectric element 214 is provided on the side of the support member 215 facing the connection shaft 212 . The piezoelectric element 214 receives the vibration of the equipment 100, vibrates the vibrator 210 having the weight 213, and the connecting shaft 212 contacts the piezoelectric element 214, thereby generating electric energy when pressure is applied.
In this embodiment, for example, the piezoelectric element 214 located on the upper side in FIG. 3 generates a positive electromotive force, and the piezoelectric element 214 located on the lower side generates a negative electromotive force. . Therefore, the power generation waveform data, which is the time-history waveform data of the amount of power generated by the piezoelectric element 214, has a substantially constant cycle centering on 0 with time, as shown in FIG. This is AC voltage waveform data that alternately takes positive and negative values at . In this way, the power generation waveform data becomes a waveform having an amplitude corresponding to the amplitude of the vibration of the equipment 100 and a frequency substantially equal to that of the vibration of the equipment 100 .

FIG. 4 is a diagram showing the correlation between the resonance frequency and the power generation amount in the vibration power generation sensor.
As shown in FIG. 4, in the vibration power generation sensor 21, the closer the frequency of the vibration transmitted from the equipment 100 to the vibration power generation sensor 21 is to the resonance frequency of the vibrator 210 provided with the weight 213, the greater the amount of power generation. The amount of power generation decreases as the distance from the resonance frequency increases. The resonance frequency of the vibrator 210 is set to be the frequency of vibration when the equipment 100 operates normally. In other words, when the equipment 100 is operating normally, the amount of power generated by the piezoelectric element 214 of the vibration power generation sensor 21 increases. When the facility equipment 100 does not operate normally for some reason and the frequency of vibration generated in the equipment 100 deviates from the frequency of vibration when the equipment 100 normally operates, the vibration power generation sensor 21 detects that the equipment 100 The vibration transmitted from the vibration power generation sensor 21 separates from the resonance frequency of the vibration power generation sensor 21, and the power generation amount decreases.

The power storage unit 22 obtains the electrical energy generated by the piezoelectric element of the vibration power generation sensor 21 and stores the electrical energy. As the power storage unit 22, for example, a capacitor can be used.
Control unit 23 monitors the amount of power stored in power storage unit 22 . When the amount of electricity stored in the electricity storage unit 22 reaches a preset power threshold value Vp (see FIG. 5), the control unit 23 receives time information indicating the time when the amount of electricity storage reaches the power threshold value Vp from the time acquisition unit 24. to get The time acquisition unit 24 uses, for example, a GPS (Global Positioning System), a radio clock, or the like. When the amount of electricity stored in the electricity storage unit 22 reaches the preset power threshold value Vp, the control unit 23 controls information indicating that the amount of electricity storage in the electricity storage unit 22 has reached the power threshold value Vp and A signal associated with the time information indicating the time of arrival at is transmitted to the transmission unit 25 . Here, the power threshold Vp is set to be lower than the maximum power amount that can be stored in the power storage unit 22 and to be equal to or greater than the power amount required for one transmission operation in the transmission unit 25 described below. . In the present embodiment, the power threshold Vp is set to be approximately equal to the amount of power required for one transmission operation in the transmission section 25 .

Upon receiving a signal from the control unit 23, the transmission unit 25 transmits the signal to the abnormality detection device 3 by communication means via a wireless LAN or the like. The transmission unit 25 consumes the electric energy stored in the power storage unit 22 when transmitting the signal. As described above, in the present embodiment, the power threshold Vp is set to be substantially equal to the amount of power required for one transmission operation. It is decremented and reset each time it sends a signal that it has reached Vp. In this way, every time the amount of power obtained by the vibration power generation sensor 21 reaches the power threshold value Vp, the transmission section 25 consumes the amount of power stored in the power storage section 22 and transmits a signal.
FIG. 5 is a diagram showing an example of changes in the amount of electricity stored in the electricity storage unit.
As shown in FIG. 5, the vibration power generation sensor 21 generates power due to the vibration of the facility equipment 100, so that the amount of electricity stored in the electricity storage unit 22 increases. (timings t1, t2, t3, t4), a signal is transmitted from the transmission unit 25 . By transmitting the signal from the transmission unit 25, the electric energy stored in the power storage unit 22 is consumed. After that, the vibration power generation sensor 21 generates power due to the vibration of the facility equipment 100, so that the amount of power stored in the power storage unit 22 increases again. In this way, while the facility equipment 100 is in operation, the amount of power in the power storage unit 22 increases due to power generation, and every time it reaches the power threshold Vp, it is consumed by signal transmission and decreases. Repeated.

As shown in FIG. 2 , the abnormality detection device 3 includes a receiver 31 , a storage 32 , a calculator 33 , a diagnostics 34 , and a result output 35 .
The receiving section 31 receives the signal transmitted from the transmitting section 25 via the communication means. The receiving unit 31 receives a signal transmitted from the transmitting unit 25 each time the power amount obtained by the vibration power generation sensor 21 reaches the power threshold value Vp. The storage unit 32 stores the signal received by the receiving unit 31 . The storage unit 32 accumulates information indicating that the amount of electricity stored in the electricity storage unit 22 has reached the power threshold value Vp and time information indicating the time when the amount of electricity storage has reached the power threshold value Vp, which are included in the received signal. memorize.
The calculation unit 33 calculates the difference between the time information included in the signal transmitted from the transmission unit 25 every time the power amount obtained by the vibration power generation sensor 21 reaches the power threshold value Vp in the reception unit 31 at the time interval ΔT (See FIG. 5). More specifically, the computing unit 33 calculates the time interval between the time information included in the signal newly received by the receiving unit 31 and the time information included in the signal received by the receiving unit 31 immediately before that. Interval ΔT is calculated.

FIG. 6 is a diagram showing the power generation amount in the vibration power generation sensor that changes depending on the operating state of the equipment. FIG. 7 is a diagram showing changes in the amount of electricity stored in the electricity storage unit when equipment is operating normally. FIG. 8 is a diagram showing changes in the amount of electricity stored in the electricity storage unit when the amplitude of vibration of the equipment increases. FIG. 9 is a diagram showing changes in the amount of electricity stored in the power storage unit when the frequency of vibration of equipment changes or when the amplitude of vibration decreases.
In FIG. 6, section A1 indicates the amount of power generated by the vibration power generation sensor 21 when the equipment 100 is operating normally. When the equipment 100 is operating normally, the vibrator 210 of the vibration power generation sensor 21 resonates with the vibration of the equipment 100 and generates a large amount of power (see FIG. 4). In this section A1, as shown in FIG. 7, the amount of electricity stored in the electricity storage unit 22 reaches the power threshold value Vp at approximately every time interval ΔT, and the signal is transmitted by the transmission unit 25 each time.

In FIG. 6, section A2 is a state in which the facility equipment 100 vibrates with a larger amplitude while maintaining the same frequency as in the case of normal operation due to some kind of abnormality occurring in the equipment 100 . In this case, the vibration of the equipment 100 remains the same frequency as when the equipment 100 is operating normally. It is done efficiently while resonating. Since the amplitude of the equipment 100 is large, the power generation amount per hour in the vibration power generation sensor 21 increases. As a result, as shown in FIG. 8, the time interval ΔT′ until the amount of electricity stored in the electricity storage unit 22 reaches the power threshold value Vp is the same as the time interval ΔT when the equipment is operating normally (see FIG. 7). becomes smaller when compared to
In addition, in contrast to section A2, when the facility equipment 100 vibrates with a smaller amplitude while maintaining the same frequency as when operating normally, the amount of power generated per hour in the vibration power generation sensor 21 decreases, and the power storage unit The time interval ΔT″ until the amount of charge in 22 reaches the power threshold Vp increases, for example, as shown in FIG.

In FIG. 6, in section A3, due to some abnormality occurring in the equipment 100, the vibration frequency of the equipment 100 is higher than when the equipment 100 is operating normally. In this case, the frequency of the vibration of the equipment 100 increases, so that the resonance frequency of the vibrator 210 of the vibration power generation sensor 21 is separated, and the power generation amount of the vibration power generation sensor 21 decreases. Even when the frequency of the vibration of the facility equipment 100 becomes lower than in the section A3, the amount of power generated by the vibration power generation sensor 21 decreases because the resonance frequency of the vibrator 210 of the vibration power generation sensor 21 is removed. As a result, as shown in FIG. 9, the time interval ΔT″ until the amount of electricity stored in the electricity storage unit 22 reaches the power threshold value Vp is the time interval ΔT″ when the equipment is operating normally (see FIG. 7 ). becomes larger compared to
Thus, the time interval ΔT increases or decreases according to the operating state of the equipment 100 compared to when the equipment 100 is operating normally.

The diagnosis unit 34 diagnoses whether or not the operating state of the equipment 100 is abnormal based on the time interval ΔT calculated as described above. The diagnosis unit 34 diagnoses that the operating state of the equipment 100 is abnormal when the time interval ΔT calculated as described above is smaller than the preset lower limit threshold or larger than the preset upper limit threshold.
FIG. 10 is a diagram showing changes in the amount of power generated by the vibration power generation sensor and changes in the amount of electricity stored in the power storage unit according to the operating state of the actual equipment. FIG. 10 particularly shows a case where the facility equipment 100 changes from a state in which it is operating normally to a state in which an abnormality has occurred and the vibration frequency has changed to a value different from that in the normal state.
As shown in FIG. 10, in the actual equipment 100, when the equipment 100 is operating normally, the vibration state (mainly the amplitude) fluctuates, and the amount of power generated by the vibration power generation sensor 21 varies. is also fluctuating. As a result, the time interval from when the signal is transmitted by the transmitting unit 25 to when the amount of power stored in the power storage unit 22 reaches the power threshold value Vp also fluctuates.
Here, it is possible to set the lower limit threshold and the upper limit threshold by assuming that the time interval ΔT when the equipment 100 operates normally has a normal distribution. For example, the lower threshold is set by subtracting a value based on the standard deviation σ from the average μ of the time interval ΔT. In this case, the lower limit threshold A can be expressed as A=μ−a×σ, for example, using a variable a that can be set to any positive value. Similarly, the upper threshold is set by adding a value based on the standard deviation σ to the mean μ. In this case, the upper threshold B can be expressed as B=μ+a×σ, for example.

As shown in FIG. 10, in the actual equipment 100, when an abnormality occurs for some reason in the operating state of the equipment 100 and the frequency of the vibration changes, the amount of power generated by the vibration power generation sensor 21 decreases. Therefore, when the equipment 100 is operating normally, the time interval from when the signal is transmitted by the transmission unit 25 until the power storage amount in the power storage unit 22 reaches the power threshold value Vp and when the signal is emitted again is is larger compared to In addition, when the amplitude of the equipment 100 changes, the amount of power generated by the vibration power generation sensor 21 increases or decreases, and accordingly, the time interval becomes larger than when the equipment 100 is operating normally. become or become smaller. The diagnosis unit 34 detects an abnormality in the equipment 100 by comparing the time interval at which the value changes according to the power generation amount with the lower limit threshold value and the upper limit threshold value.
Here, if the value of the variable a is set too small, the upper limit threshold becomes excessively small and the lower limit threshold becomes large, and the equipment 100 operates normally but temporarily performs an exceptional operation. For example, this may be misdiagnosed as abnormal due to hypersensitivity. Therefore, it is desirable to set the value of the variable a to a moderately large value. For example, it is desirable to set the variable a to a value of 3 or more.
For example, in the example of FIG. 10, the time interval ΔT when the equipment 100 operates normally has an average value μ=1.15 and a standard deviation σ=0.53. On the other hand, after the frequency has changed due to the occurrence of an abnormality in the equipment 100, the time interval has a value of approximately 11.5. By substituting these values into the equation expressing the upper limit threshold value B and calculating back the variable a, a=19.6 is obtained. Therefore, if a=3 is set as described above, it is possible to diagnose that the operation status of the equipment 100 is abnormal when the time interval changes as shown in FIG.

The result output unit 35 outputs the diagnosis result of the diagnosis unit 34 as necessary. When the diagnosis unit 34 diagnoses that the calculated time interval ΔT is smaller than the preset lower limit threshold or larger than the upper limit threshold, and the operating state of the equipment 100 is abnormal, the result output unit 35 Information indicating that the operating state of the equipment 100 is abnormal is output to the outside. The result output unit 35 is, for example, a monitor provided in the abnormality detection device 3, as shown in FIG. be able to. The result output unit 35 may output to the outside that an abnormality has occurred in the operating state of the equipment 100 by an alarm sound, an alarm voice, or the like. Further, the result output unit 35 transmits a signal for stopping the operation of the equipment 100 to the control device that controls the operation of the equipment 100 when the operating state of the equipment 100 is diagnosed as abnormal. You may make it Even if the diagnosis unit 34 does not diagnose that the operating state of the equipment 100 is abnormal, the result output unit 35 outputs information indicating that the operating state of the equipment 100 is normal. good.

FIG. 11 is a flow chart showing the flow of the abnormality detection method in the abnormality detection system according to the first embodiment of the present invention.
As shown in FIG. 11, in the abnormality detection system 1, in order to detect an abnormality in the equipment 100, the control unit 23 monitors the amount of electric power stored in the power storage unit 22 while the equipment 100 is in operation. (Step S1). During the operation of the equipment 100 , electric power generated by the vibration power generation sensor 21 in response to the vibration of the equipment 100 is stored in the power storage unit 22 .
The control unit 23 confirms at regular time intervals whether or not the amount of power in the power storage unit 22 has reached the power threshold value Vp (step S2). As a result, if the power amount of the power storage unit 22 has not reached the power threshold value Vp (NO in step S2), the process returns to step S1 to continue monitoring the power storage amount.
In step S2, when the amount of power in power storage unit 22 reaches power threshold Vp (Yes in step S2), control unit 23 outputs a predetermined signal (step S3). In this case, in the control unit 23, the time acquisition unit 22 acquires time information indicating the time when the amount of electricity stored in the power storage unit 22 reaches the power threshold value Vp. Further, the control unit 23 transmits a signal that associates information indicating that the amount of electricity stored in the electricity storage unit 22 has reached the power threshold value Vp with time information indicating the time when the amount of electricity storage has reached the power threshold value Vp. to the anomaly detection device 3.

When the signal is transmitted from the transmitter 25, the receiver 31 of the abnormality detection device 3 receives the signal (step S11). When the abnormality detection device 3 receives the signal, the information indicating that the amount of electricity stored in the electricity storage unit 22 has reached the power threshold value Vp and the time indicating the time when the amount of electricity storage has reached the power threshold value Vp are included in the received signal. information is stored in the storage unit 32 (step S12).
After that, the calculation unit 33 calculates a time interval ΔT for receiving signals from the transmission unit 25 (step S13). The calculator 33 calculates a time interval ΔT, which is the interval between the time information contained in the signal newly received by the receiver 31 and the time information contained in the signal received by the receiver 31 immediately before that. .
Next, the diagnosis unit 34 determines whether or not there is an abnormality in the operating state of the equipment 100 (step S14). For this, the diagnosis unit 34 determines whether the calculated time interval ΔT is smaller than a preset lower limit threshold or larger than a preset upper limit threshold. resulting in. When the time interval ΔT is smaller than the preset lower limit threshold or larger than the upper limit threshold, it is diagnosed that the operating state of the equipment 100 is abnormal.
After that, the result output unit 35 outputs the diagnosis result of the diagnosis unit 34 (step S15). When the diagnosis unit 34 diagnoses that the operating state of the equipment 100 is abnormal, the result output unit 35 outputs information indicating that the operating state of the equipment 100 is abnormal. At this time, if the diagnosis unit 34 does not diagnose that the equipment 100 is operating abnormally, the result output unit 35 outputs information indicating that the equipment 100 is operating normally. may

According to the abnormality detection system as described above, the abnormality detection system 1 for detecting an abnormality in the facility equipment 100 includes the facility equipment side device 2 attached to the facility equipment 100 and the abnormality detection device 3. The equipment-side device 2 is set so that the resonance frequency is the frequency of vibration when the equipment 100 operates normally. Each time the obtained power amount reaches the power threshold value Vp, it consumes the power amount and transmits a signal. A diagnostic unit 34 that diagnoses whether the operating state of the equipment 100 is abnormal based on the time interval ΔT for receiving the signal.
With such a configuration, the vibration power generation sensor 21 generates power by vibration generated by the equipment 100 . When the power amount obtained by the vibration power generation sensor 21 reaches the power threshold value Vp, the facility device side device 2 transmits a signal by the transmission unit 25 . Since the amount of power obtained by the vibration power generation sensor 21 is consumed by transmitting the signal from the transmission unit 25, the facility equipment side device 2 newly obtains power from the vibration power generation sensor 21 after the power amount is consumed. When the power amount reaches the power threshold value Vp again, the transmitter 25 transmits a signal. Thus, the signal is repeatedly transmitted at time intervals ΔT.
Further, the resonance frequency of the vibration power generation sensor 21 is set to be the frequency of vibration when the equipment 100 operates normally. Therefore, when the equipment 100 is operating normally, the vibration power generation sensor 21 resonates with the vibration of the equipment 100 and the amount of power generation increases. When the facility equipment 100 is not operating normally and the frequency of the vibration emitted by the equipment 100 increases or decreases compared to when it is operating normally and deviates from the resonance frequency of the vibration power generation sensor 21, Vibration in the vibration power generation sensor 21 is suppressed, and the amount of power generation is reduced. In addition, when the equipment 100 is not operating normally and the amplitude of the vibration generated by the equipment 100 increases compared to when it is operating normally, the amount of power generated by the vibration power generation sensor 21 increases, If the amplitude decreases, the amount of power generated will decrease. In any case, as a result, when the equipment 100 is not operating normally, the amount of power generation is greater or less than when the equipment 100 is operating normally.
Here, if the amount of power generated by the vibration power generation sensor 21 is large, the amount of power obtained by the vibration power generation sensor 21 reaches the power threshold value Vp more quickly, so the time interval ΔT at which the signal is transmitted by the transmission unit 25 becomes shorter. Conversely, when the amount of power generated by the vibration power generation sensor 21 is small, the time interval ΔT at which the transmission unit 25 transmits the signal becomes large. That is, when the facility equipment 100 is not operating normally, the time interval ΔT at which the signal is received by the receiving unit 31 is larger or smaller than when the equipment 100 is operating normally. . The diagnosis unit 34 of the abnormality detection device 3 diagnoses whether or not the operating state of the equipment 100 is abnormal based on this time interval ΔT.
Thus, in the configuration as described above, when there is a large difference in either the frequency or the amplitude of the vibration generated by the equipment 100 when the equipment 100 is operating normally, the equipment Since it can be determined that the operating state of the equipment 100 is abnormal, the abnormality of the facility equipment 100 can be detected with high accuracy.
Further, basically, one vibration power generation sensor 21 is required to detect an abnormality in the equipment 100 as described above. In addition to the vibration power generation sensor 21, no other type of sensor is particularly required. Therefore, the configuration can be simplified.
In this way, it is possible to provide the abnormality detection system 1 for the equipment 100 that can accurately detect an abnormality in the equipment 100 with a simple configuration without using a sensor that requires power supply.

In addition, the time interval ΔT when the equipment 100 operates normally is assumed to be normally distributed, and the lower limit threshold is obtained by subtracting the value (a × σ) based on the standard deviation σ from the average value μ of the normal distribution. The upper threshold is set by adding a value (a×σ) based on the standard deviation σ to the average μ, and the diagnostic unit 34 determines whether the time interval ΔT for receiving the signal is smaller than the lower threshold. , the operating state of the equipment 100 is diagnosed as being abnormal.
As described above, the diagnosis unit 34 of the abnormality detection device 3 determines the time interval ΔT at which a signal is transmitted from the vibration power generation device 2 each time the amount of power obtained by the vibration power generation sensor 21 reaches the power threshold value Vp. It is used as a reference for diagnosing whether the operating state of the device 100 is abnormal.
Here, according to the above configuration, the time interval ΔT at which the signal is received by the receiving unit 31 when the equipment 100 is operating normally is regarded as a normal distribution, and the average value μ and the standard deviation of the normal distribution A lower threshold value and an upper threshold value are set based on σ, and if the time interval ΔT for receiving a signal is smaller than the lower threshold value or larger than the upper threshold value, the operating state of the equipment 100 is determined to be abnormal. Diagnosis is. As a result, even if there are variations (fluctuations) in the vibration state in the operating state of the equipment 100, it is possible to accurately detect an abnormality in the equipment 100. FIG.

The vibration power generation sensor 21 includes a base 211 that receives vibrations generated by the equipment 100, a weight 213 connected to the base 211 via a connection shaft 212, and a weight 213 connected to the base 211 at a position spaced apart from the connection shaft 212. When the equipment 100 vibrates, the weight 213 vibrates, and pressure acts on the piezoelectric element 214 due to resonance, whereby the piezoelectric element 214 generates power.
According to such a configuration, when the equipment 100 vibrates, the base 211 of the vibration power generation sensor 21 receives the vibration generated by the equipment 100 . Then, the base 211 vibrates together with the equipment 100, and the weight 213 connected to the base 211 via the connection shaft 212 vibrates. Due to resonance with the vibration of the weight 213 , pressure acts on the piezoelectric element 214 and electric power is generated in the piezoelectric element 214 . By using the vibration power generation sensor 21 having such a configuration, the abnormality detection system 1 can be appropriately realized.

(Modified example of the first embodiment)
Next, a modification of the anomaly detection system shown as the first embodiment will be described.
In the above-described first embodiment, the time interval ΔT when the equipment 100 operates normally is assumed to have a normal distribution, and the lower limit threshold A is the average μ of the time interval ΔT, and the standard deviation σ is a value based on By subtracting, A = μ-a × σ is set, and the upper limit threshold B is set as B = μ + a × σ by adding a value based on the standard deviation σ to the average value μ , the diagnosis unit 34 diagnoses that the operating state of the equipment 100 is abnormal when the time interval ΔT is smaller than the lower limit threshold or larger than the upper limit threshold.
This is because when the deviation value of the time interval ΔT is α, the time interval ΔT is given by the following equation (1)
ΔT=μ+α×σ (1)
and the value of the time interval ΔT in formula (1) is an appropriate value as an upper threshold value and a lower threshold value that can diagnose an abnormality in the equipment 100 when it occurs. based on the idea of setting
In this modified example, the diagnosis unit 34 uses the deviation value α of the signal reception time interval ΔT instead of the signal reception time interval ΔT for diagnosing an abnormality of the equipment 100 . More specifically, the following equation (2) related to the deviation value α, which is a modified equation (1)
α=(ΔT−μ)/σ (2)
Based on this, the diagnosis unit 34 subtracts the average μ of the time interval ΔT when the equipment 100 is operating normally from the time interval ΔT at which the equipment 100 receives the signal. The deviation value α is calculated by dividing by the standard deviation σ of the time interval ΔT during normal operation. In this way, by dividing by the standard deviation σ, the variation width is standardized by the standard deviation σ.
Then, the diagnosis unit 34 compares the deviation value α with the upper threshold value and the lower threshold value appropriately set for the deviation value α, and if the deviation value α is smaller than the lower threshold value or larger than the upper threshold value, the equipment Diagnose that the operating state of the device 100 is abnormal.
When the equipment 100 operates normally, the difference (ΔT−μ) is approximately 0, so the deviation value α is also 0. Therefore, the positive threshold value may be set to, for example, 3, and if the absolute value of the deviation value α is greater than the positive threshold value, it may be diagnosed that the operating state of the equipment 100 is abnormal. When the deviation value α is directly compared with the upper threshold value and the lower threshold value, it is desirable to set the upper threshold value and the lower threshold value to, for example, 3 and -3, respectively.

Thus, in this modification as well, the diagnostic unit 34 uses the deviation value α calculated from the time interval ΔT to receive the signal according to the equation (2). , to diagnose whether the operating state of the equipment 100 is abnormal.
In particular, in this modification, the time interval ΔT at which the equipment 100 operates normally is assumed to have a normal distribution, and the diagnostic unit 34 determines from the time interval ΔT at which the signal is received that the time interval ΔT at which the equipment 100 operates normally The deviation value α is calculated by dividing the difference obtained by subtracting the average value μ of the time interval ΔT by the standard deviation σ of the time interval ΔT when the equipment 100 operates normally, and based on the deviation value α, the equipment Diagnose whether the operating state of the device 100 is abnormal.
Even in this case, similarly to the first embodiment, anomaly detection of the equipment 100 can be performed with a simple configuration without using a sensor that requires a power supply, and the anomaly of the equipment 100 can be detected with high accuracy. system can be provided.

[Second embodiment]
Next, an abnormality detection system according to the first embodiment of the present invention will be described. In particular, the second embodiment is also a further modification of the modification of the first embodiment. In the anomaly detection system 1A (see FIG. 1) of the second embodiment, the details of processing in the diagnosis section 34A are different from those of the first embodiment and the modification of the first embodiment. Therefore, in the second embodiment, the processing contents of the diagnosis unit 34A will be mainly described, and the description of the same configuration as that of the abnormality detection system of the first embodiment and the modified example of the first embodiment will be omitted.
FIG. 12 is a diagram showing changes in the amount of power generated by the vibration power generation sensor when an abnormality occurs in equipment that is operating normally at a certain point in time. 13 is a diagram showing changes in the amount of electricity stored in the electricity storage unit in the case of FIG. 12. FIG. In FIGS. 12 and 13, the state in which the equipment 100 is operating normally is shown as section A4, and the state in which the equipment 100 is malfunctioning is shown as section A5.

For example, if the facility equipment 100 is partially damaged and strong and very short whisker-like pulse-like vibrations occur periodically, the amount of power generated by the vibration power generation sensor 21 will also change as shown in FIG. 12, the power waveform has a strong and short pulse-like component. In this case, the increase in amplitude due to the pulse-like component occurs within a short period of time, so although the amount of power generated by the vibration power generation sensor 21 increases, the amount of increase is very small. Therefore, the time interval ΔT at which the transmission unit 25 of the equipment device 2 transmits signals is slightly shorter than when the equipment 100 operates normally.
For example, in FIG. 13, the time interval ΔT has an average value μ=3.47 seconds in a state in which the equipment 100 is operating normally in section A4. On the other hand, the first time interval ΔT in section A5, in which an abnormality occurs in the facility equipment 100 and pulse-like vibration occurs periodically, is 2.83 seconds, which is an interval smaller than the average value μ. It has become.
In the case of FIG. 12, the standard deviation σ is 0.34 seconds in the state in which the equipment 100 is operating normally in section A4. Here, the lower limit threshold A and the upper limit threshold B when the variable a = 3 in the first embodiment are, respectively,
A = μ - a x σ = 3.47 - 3 x 0.34 = 2.45
B=μ+a×σ=3.47+3×0.34=4.49
becomes. That is, in this case, the time interval ΔT=2.83 seconds is equal to or more than the lower limit threshold value A and equal to or less than the upper limit threshold value B, even though the equipment 100 has an abnormality. The diagnosis unit 34 in the form does not diagnose that the operating state of the equipment 100 is abnormal.
Similarly in the modified example of the first embodiment, in equation (2), the deviation value α is
α=(ΔT−μ)/σ=(2.83−3.47)/0.34=−1.88
is relatively close to 0, which is the average value of the deviation value α when the equipment 100 is operating normally, and the diagnosis unit 34 does not diagnose that the operating state of the equipment 100 is abnormal even in this case.
In this way, when the difference in the time interval ΔT between when the equipment 100 operates normally and when an abnormality occurs is small, the diagnostic unit 34 determines whether the value of the time interval ΔT for receiving the signal is large. Therefore, even if an attempt is made to diagnose whether the operating state of the equipment 100 is abnormal, there is a possibility that the diagnosis cannot be performed correctly.

Here, the difference obtained by subtracting the average value μ of the time interval ΔT when the equipment 100 operates normally from the time interval ΔT for receiving the signal is the standard deviation of the time interval when the equipment 100 operates normally. Consider calculating the deviation value α by dividing, ie, as shown in equation (2). Such a deviation value α tends to be a value close to 0 when the equipment 100 is operating normally. Since ΔT is slightly shorter than the time interval ΔT when the equipment 100 operates normally, it tends to be a negative value that is slightly smaller than the value when the equipment 100 operates normally. Actually, in the above example, the deviation value α is -1.88. The deviation value α calculated in this way is a value that does not change greatly from 0 in the normal state even if a pulse-like vibration occurs. cannot be used. However, when pulse-like vibration occurs periodically multiple times, if the cumulative value of the deviation value α within a certain time range is calculated, the difference from the normal value is accumulated. , the value should reflect the difference from the normal value to a greater extent.
Based on this idea, the diagnosis unit 34A in the present embodiment calculates the cumulative value of the deviation value α or the absolute value of the cumulative value of the deviation value α, and uses this to determine whether the operating state of the equipment 100 is abnormal. Diagnose whether or not. In the present embodiment, the diagnosis unit 34A calculates the absolute value R of the cumulative value of the deviation value α as R=|Σα|
, and using this, it is diagnosed whether or not the operating state of the equipment 100 is abnormal.
FIG. 14 is a diagram showing changes in the deviation value α and the absolute value R of the accumulated value in the case of FIG. In FIG. 14, the deviation value α is drawn by a circle indicated as P1, and the absolute value R of the cumulative value is drawn by a triangle indicated by P2. When an abnormality occurs in the equipment 100, the absolute value R of the cumulative value is a value larger than (the absolute value of) the deviation value α.
It should be noted that the deviation value α is generally close to 0 when the equipment 100 is operating normally, but strictly speaking, it is different from 0. Therefore, if the time range for calculating the cumulative value is too long, even if the equipment 100 is operating normally, the absolute value of the cumulative value becomes too large, and the operating state of the equipment 100 is abnormal. , there is a possibility that the diagnosis unit 34A diagnoses. Therefore, it is necessary to appropriately determine the time range for calculating the cumulative value as a time range that is not too long so as to prevent such misdiagnosis.

Further, in order to perform diagnosis more accurately, the diagnosis unit 34A assumes that the absolute value R of the cumulative value when the equipment 100 operates normally has a normal distribution, and determines the absolute value R of the cumulative value when the equipment 100 Calculate the deviation value β of the cumulative value by dividing by the standard deviation σ _R of the absolute value R of the cumulative value in normal operation. Accurately, to calculate the deviation value β of the cumulative value, the difference obtained by subtracting the average value μ _R of the absolute value R of the cumulative value when the equipment 100 is operating normally from the absolute value R of the cumulative value should be divided by the standard deviation σ _R of the absolute value R of the accumulated value when the equipment 100 operates normally. However, since the average value _μR of the absolute values R of the cumulative values when the facility equipment 100 is operating normally becomes a value substantially equal to 0, the above division is performed without subtracting the average value _μR . only, the deviation value β of the accumulated value is calculated. In this way, by dividing by the standard deviation _σR , the variation width is standardized by the standard deviation _σR .
The diagnosis unit 34A compares the deviation value β of the cumulative values calculated in this manner with the determination threshold value, and if the deviation value β of the cumulative values is larger than the determination threshold value, the operating state of the equipment 100 is abnormal. Diagnose there is. As a result, even when an abnormality occurs such that the amount of power generated by the vibration power generation sensor 21 is only slightly different from when the equipment 100 operates normally, the abnormality of the equipment 100 can be accurately detected. It becomes possible.

As described above, since the deviation value β of the cumulative value sensitively reflects minute changes in the behavior of the equipment 100, an abnormality of the equipment 100 can be detected with high accuracy. However, on the other hand, even though the equipment 100 is operating normally, there is a possibility of erroneously diagnosing that the equipment 100 is abnormal.
In order to suppress this, in the present embodiment, the diagnosis unit 34A performs the abnormality diagnosis based on the deviation value α as described as the modification of the first embodiment as the primary diagnosis, and then , abnormality diagnosis based on the deviation value β of the cumulative value as described above is executed as a secondary diagnosis.
The abnormality detection method according to the second embodiment will be described with reference to FIGS. 11 and 15. FIG. FIG. 15 is a flow chart showing the flow of an anomaly detection method in an anomaly detection system according to the second embodiment.

In the abnormality detection system 1A, in order to detect an abnormality in the equipment 100, the control unit 23 monitors the amount of electric power stored in the power storage unit 22 while the equipment 100 is in operation (step S1). During the operation of the equipment 100 , electric power generated by the vibration power generation sensor 21 in response to the vibration of the equipment 100 is stored in the power storage unit 22 .
The control unit 23 confirms at regular time intervals whether or not the amount of power in the power storage unit 22 has reached the power threshold value Vp (step S2). As a result, if the power amount of the power storage unit 22 has not reached the power threshold value Vp (NO in step S2), the process returns to step S1 to continue monitoring the power storage amount.
In step S2, when the amount of power in power storage unit 22 reaches power threshold Vp (Yes in step S2), control unit 23 outputs a predetermined signal (step S3). In this case, in the control unit 23, the time acquisition unit 22 acquires time information indicating the time when the amount of electricity stored in the power storage unit 22 reaches the power threshold value Vp. Further, the control unit 23 transmits a signal that associates information indicating that the amount of electricity stored in the electricity storage unit 22 has reached the power threshold value Vp with time information indicating the time when the amount of electricity storage has reached the power threshold value Vp. to the anomaly detection device 3.

When the signal is transmitted from the transmitter 25, the receiver 31 of the abnormality detection device 3 receives the signal (step S11). When the abnormality detection device 3 receives the signal, the information indicating that the amount of electricity stored in the electricity storage unit 22 has reached the power threshold value Vp and the time indicating the time when the amount of electricity storage has reached the power threshold value Vp are included in the received signal. information is stored in the storage unit 32 (step S12).
After that, the calculation unit 33 calculates a time interval ΔT for receiving signals from the transmission unit 25 (step S13). The calculator 33 calculates a time interval ΔT, which is the interval between the time information contained in the signal newly received by the receiver 31 and the time information contained in the signal received by the receiver 31 immediately before that. .

Next, the diagnostic unit 34A determines whether there is an abnormality in the operating state of the equipment 100 (step S20). First, as shown in FIG. 15, the diagnosis unit 34A subtracts the average value μ of the time intervals ΔT when the equipment 100 is operating normally from the time intervals ΔT for receiving signals (ΔT −μ) is divided by the standard deviation σ of the time interval ΔT when the equipment 100 operates normally to calculate the deviation value α (step S21).
Using this deviation value α, the diagnosis unit 34A performs primary diagnosis. Specifically, the diagnosis unit 34A compares the absolute value of the deviation value α with a first determination threshold set to 3, for example (step S22).
In this primary diagnosis, if the absolute value of the deviation value α is greater than the first determination threshold (Yes in step S22), the diagnosis unit 34A diagnoses that the operating state of the equipment 100 is abnormal (step S27). , the process proceeds to step S15 in FIG. If the absolute value of the deviation value α is less than or equal to the first determination threshold (No in step S22), the process proceeds to step S23.
In step S23, the diagnosis unit 34A compares the absolute value of the deviation value α with a second determination threshold set to 1, for example.
If the absolute value of the deviation value α is equal to or less than the second determination threshold (No in step S23), the diagnosis unit 34A diagnoses that the operating state of the equipment 100 is normal because the deviation value α is sufficiently small ( Step S26), the process transitions to step S15 in FIG. If the absolute value of the deviation value α is greater than the second determination threshold (No in step S22), the process proceeds to step S24.

Thus, since the absolute value of the deviation value α is equal to or less than the first determination threshold value, it cannot be diagnosed that the operating state of the equipment 100 is abnormal, and the absolute value of the deviation value α is less than the second determination threshold value. Since it is large, when it cannot be judged that the operating state of the equipment 100 is normal, the process transitions to step S24. In such a case, the diagnosis unit 34A performs secondary diagnosis.
Specifically, the diagnosis unit 34A calculates the cumulative value of the deviation value α over a certain period of time, and calculates the absolute value R of the cumulative value as the absolute value R of the cumulative value when the equipment 100 is operating normally. A deviation value β of the accumulated value is calculated by dividing by the standard deviation _σR (step S24).
Then, the diagnosis unit 34A compares the deviation value β of the cumulative value with a third determination threshold value (determination threshold value) set to 3, for example (step S25).
If the deviation value β of the cumulative values is equal to or less than the third determination threshold (No in step S25), the diagnosis unit 34A diagnoses that the operating state of the equipment 100 is normal (step S26), and step S15 in FIG. Transition to If the deviation value β of the cumulative values is greater than the third determination threshold (No in step S25), the diagnosis unit 34A diagnoses that the operating state of the equipment 100 is abnormal (step S27), and proceeds to step S15 in FIG. Transition.
After that, returning to FIG. 11, the result output unit 35 outputs the diagnosis result of the diagnosis unit 34A (step S15).

Such an anomaly detection system 1A is an anomaly detection system 1A that detects an anomaly of the equipment 100, as in the first embodiment, and includes an equipment side device 2 attached to the equipment 100 and an anomaly detection device 3 and a vibration power generation sensor 21 which is set so that the resonance frequency of the equipment device 2 is the frequency of vibration when the equipment 100 operates normally, and generates power by the vibration generated by the equipment 100. , and a transmission unit 25 that consumes the power amount and transmits a signal every time the power amount obtained by the vibration power generation sensor 21 reaches the power threshold value Vp, and the abnormality detection device 3 receives the signal and a diagnosis unit 34A for diagnosing whether the operating state of the equipment 100 is abnormal based on the time interval ΔT for receiving the signal.
Similarly to the first embodiment, such an abnormality detection system 1A can accurately detect an abnormality in the equipment 100 with a simple configuration without using a sensor that requires power supply.

In addition, the diagnosis unit 34A calculates the difference obtained by subtracting the average value μ of the time intervals ΔT when the equipment 100 is operating normally from the time interval ΔT for receiving the signal, and calculates the time when the equipment 100 is normally operating. Calculate the absolute value R of the cumulative value of the deviation value α obtained by dividing by the standard deviation σ of the interval ΔT within a certain period of time, and calculate the absolute value R of the cumulative value when the equipment 100 operates normally. When the deviation value β of the cumulative value obtained by dividing by the standard deviation σ _R of the absolute value R of the cumulative value is larger than the determination threshold (third determination threshold), it is determined that the operating state of the equipment 100 is abnormal. Diagnose.
In particular, in the present embodiment, the diagnosis unit 34A calculates the deviation value α, and if the absolute value of the deviation value α is greater than the first determination threshold value, diagnoses that the operating state of the equipment 100 is abnormal, If the absolute value of the deviation value α is equal to or less than the second determination threshold that is smaller than the first determination threshold, it is diagnosed that the operating state of the equipment 100 is normal, and the absolute value of the deviation value α is equal to or less than the first determination threshold. and is greater than the second determination threshold, calculate the deviation value β of the cumulative value, and diagnose whether the operating state of the equipment 100 is abnormal based on the deviation value β of the cumulative value. .
According to such a configuration, as already explained, it is possible to accurately detect an abnormality in the equipment 100 .

(Modification of Second Embodiment)
In the second embodiment, the diagnosis unit 34A calculates the deviation value α from the time interval ΔT, calculates the absolute value R of the cumulative value of the deviation value α within a certain period of time, and uses this to The equipment 100 is diagnosed as abnormal, but if there is no problem in terms of accuracy, the equipment 100 may be diagnosed using the cumulative value without calculating the absolute value.
In the second embodiment, the diagnosis unit 34A diagnoses an abnormality in the equipment 100 using the deviation value α as the primary diagnosis, and then uses the absolute value R of the cumulative value as the secondary diagnosis. However, if there seems to be no problem in terms of accuracy, the abnormality of the equipment 100 is diagnosed using only the absolute value R of the cumulative value without performing the primary diagnosis. It may be configured as

(Another modified example of the first and second embodiments)
It should be noted that the anomaly detection system of the present invention is not limited to the above embodiments and modified examples described with reference to the drawings, and various other modified examples are conceivable within the technical scope thereof.
For example, in each of the above-described embodiments, the time acquisition unit 24 is provided in the equipment device 2, but the present invention is not limited to this.
For example, the time acquisition unit 24 may be provided in the abnormality detection device 3 . In this case, in the equipment-side device 2, when the control unit 23 causes the power storage amount in the power storage unit 22 to reach the power threshold value Vp, the transmission unit 25 indicates that the power storage amount in the power storage unit 22 has reached the power threshold value Vp. Send information. In the abnormality detection device 3, when the signal is received, the time acquisition unit 24 provided in the abnormality detection device 3 acquires the time at which the signal is received, and the time at which the amount of electricity stored in the electricity storage unit 22 reaches the power threshold value Vp is obtained. information. The calculation unit 33 calculates the time interval ΔT based on the time information thus acquired.

In particular, when the time acquisition unit 24 is provided in the abnormality detection device 3 in this way, the time elapsed from the time when the reception unit 31 last received the signal can be measured on the abnormality detection device 3 side. becomes possible. For example, when the amount of power generated by the vibration power generation sensor 21 is significantly reduced due to an abnormality occurring in the equipment 100, the signal is not transmitted from the equipment 2 for a long period of time. In such a case, in each of the above-described embodiments, since the abnormality detection device 3 is configured to only wait for a signal from the equipment side device 2, it diagnoses that the operating state of the equipment 100 is abnormal. This delays the detection of anomalies. On the other hand, as described above, if the anomaly detection device 3 side is configured to measure the time that has passed since the reception unit 31 last received the signal, the diagnosis unit 34 can detect the elapsed time , it becomes possible to diagnose that the operating state of the facility equipment 100 is abnormal when it becomes larger than a predetermined time threshold. Thereby, the abnormality of the equipment 100 can be quickly detected.
In such a configuration, even though the equipment 100 is operating normally, the communication status between the transmitter 25 and the receiver 31 deteriorates, and the signal is not transmitted to the abnormality detection device 3. It becomes possible to detect even such a defect.

(Other modifications)
Moreover, the equipment 100 to be monitored in the abnormality detection systems 1 and 1A may be anything as long as it generates vibration.
Also, the vibration power generation sensor 21 may have a configuration different from that described in each of the above embodiments. For example, the vibration power generation sensor has a base portion and a weight connected to the base portion via a connection shaft as in each of the above embodiments, but unlike each of the above embodiments, the vibration power generation sensor has a piezoelectric element connected to the connection shaft. It is good also as a structure joined along. In this case, when the equipment 100 vibrates and the weight vibrates, the connection shaft bends, and the piezoelectric element detects the stress generated thereby to generate power. Alternatively, the connecting shaft itself may be realized by a piezoelectric element. Even when such a vibration power generation sensor is used, it is possible to appropriately realize an abnormality detection system as in each of the above-described embodiments.

Basically, the vibration power generation sensor has the property that the amount of power generation increases when it resonates with the vibration of the facility equipment, especially at the frequency of the vibration, and the amount of power generation decreases at other frequencies. If there is, it can be applied even if it does not have a piezoelectric element as in each of the above embodiments.
For example, an electromagnetic induction type vibration power generation sensor 40 as shown in FIG. 16 can be applied to the abnormality detection system. The vibration power generation sensor 40 includes a spring 41, a weight 42, a coil 43, and a housing 44 having these inside. One end of the spring 41 is fixed to the housing 44 . The other end of the spring 41 is fixed to a weight 42 made of a magnet. The weight 42 is provided movably in the direction in which the spring 41 extends with respect to the housing 44 . The coil 43 is provided so as to circulate around the weight 42 . The housing 44 is fixed to equipment.
In such a configuration, when the equipment vibrates and the housing 44 also vibrates, the spring 41 expands and contracts, and the weight 42 moves back and forth in the direction in which the spring 41 extends, for example in the horizontal direction in FIG. . Then, an induced current alternately flows through the coil 43 in opposite directions according to the direction in which the weight 42 moves. By extracting this induced current, it is possible to obtain power generation waveform data as described in each of the above embodiments.

Alternatively, an electrostatic induction type vibration power generation sensor 50 as shown in FIG. 17 can be applied to the abnormality detection system. The vibration power generation sensor 50 includes a spring 51, a weight 52, a resistor 53, a metal body 54, a charged body 55, and a housing 56 containing them. One end of the spring 51 is fixed to the housing 56 . The other end of the spring 51 is fixed to a weight 52 made of a conductor. The weight 52 is provided movably in the direction in which the spring 51 extends with respect to the housing 56 . The weight 52 is connected via a resistor 53 to a metal body 54 that is a conductor. The conductor 54 side of the resistor 53 is grounded. A charged body 55 such as an electret is provided on the weight 52 and the metal body 54 so as to face them.
In such a configuration, when the equipment vibrates and the housing 56 also vibrates, the spring 51 expands and contracts, and the weight 52 moves back and forth in the direction in which the spring 51 extends, for example, in the horizontal direction in FIG. . For example, if the charged body 55 has a negative charge, when the weight 52 moves to the right and approaches the charged body 55, it will be charged to have a positive charge. Moving to the right via 53 causes current to flow in the left direction. Conversely, when the weight 52 moves to the left and is separated from the charged body 55, the positive charge charged on the weight 52 flows out through the resistor 53, causing a rightward current to flow. By extracting the current generated in this manner, it is possible to obtain power generation waveform data as described in each of the above embodiments.

16 and 17, the frequency can be adjusted by the stiffness of the springs 41 and 51 and the weight of the weights 42 and 52. FIG.
In this way, by setting the resonance frequency to the frequency of vibration when the equipment operates normally, the vibration power generation sensors 40 and 50 shown in FIGS. It can be used instead of the vibration power generation sensor 21 of the form.
That is, an abnormality detection system for detecting an abnormality in the equipment is provided with an equipment-side device attached to the equipment and an abnormality detection device, and the equipment-side device has a resonance frequency that allows the equipment to operate normally. Each time the power amount obtained by the vibration power generation sensors 40 and 50, which are set to be the frequency of the actual vibration and generate power by the vibration generated by the equipment, and the power amount obtained by the vibration power generation sensors 40 and 50, reaches the power threshold, a transmitting unit that consumes power to transmit a signal, and the anomaly detection device includes a receiving unit that receives the signal; and a diagnostic unit for diagnosing that the operating state of the equipment is abnormal.
Even in such a case, it is possible to provide an anomaly detection system for facility equipment that does not use a sensor that requires power supply and that can accurately detect an anomaly in facility equipment with a simple configuration.

In addition to this, it is possible to select the configurations described in the above embodiments or to change them to other configurations as appropriate without departing from the gist of the present invention.

1, 1A Abnormality detection system 34 Diagnosis unit 2 Equipment side device 100 Equipment 3 Abnormality detection device 211 Base 21, 40, 50 Vibration power generation sensor 212 Connection shaft 25 Transmitter 213 Weight 31 Receiver 214 Piezoelectric element

Claims (4)

An anomaly detection system for detecting anomalies in equipment,
An equipment-side device attached to the equipment, and an anomaly detection device,
The equipment side device is
a vibration power generation sensor whose resonance frequency is set to be the frequency of vibration when the equipment operates normally, and which generates power by the vibration generated by the equipment;
a transmitting unit that consumes the amount of power and transmits a signal each time the amount of power obtained by the vibration power generation sensor reaches a power threshold;
with
The anomaly detection device is
a receiver that receives the signal;
a diagnosis unit that diagnoses whether the operating state of the equipment is abnormal based on the time interval for receiving the signal;
An anomaly detection system for facility equipment, comprising: It is assumed that the time interval when the equipment operates normally is normally distributed, and a lower threshold value is set by subtracting a value based on the standard deviation from the average value of the normal distribution, and the average value is the standard An upper threshold is set by adding the value based on the deviation,
The diagnosis unit diagnoses that the operation state of the facility equipment is abnormal when the time interval for receiving the signal is smaller than the lower limit threshold or larger than the upper limit threshold. 2. The abnormality detection system for equipment according to 1. The diagnosis unit
Divide the difference obtained by subtracting the average value of the time intervals when the equipment operates normally from the time interval for receiving the signal by the standard deviation of the time intervals when the equipment operates normally. Calculate the absolute value of the cumulative value within a certain time of the deviation value obtained by
When the deviation value of the cumulative value obtained by dividing the absolute value of the cumulative value by the standard deviation of the absolute value of the cumulative value when the equipment operates normally is larger than the judgment threshold, 2. An abnormality detection system for facility equipment according to claim 1, which diagnoses that the operating state of the facility equipment is abnormal. The vibration power generation sensor includes a base for receiving vibrations generated by the equipment, a weight connected to the base via a connection shaft, and a piezoelectric element connected to the base at a position spaced apart from the connection shaft. 4. The apparatus according to any one of claims 1 to 3, wherein when the equipment vibrates, the weight vibrates, and pressure acts on the piezoelectric element due to resonance, whereby the piezoelectric element generates power. Abnormality detection system for facility equipment.

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