JP2672237B2 - Output method of abnormality information in online facility diagnosis system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of outputting abnormality information in an online facility diagnosis system, and more particularly to a method of outputting abnormality information after determining whether or not to output abnormality information. .

[0002]

2. Description of the Related Art Generally, the output of abnormality information in a facility diagnosis system such as a vibration diagnosis having a large number of sensors is judged once a hour by comparing a measured value with a certain threshold value. Here, as a method of determining the threshold value, generally, an empirical numerical value determined from past data or the like is input. Further, there is known a threshold value setting device which determines by statistical processing as shown in JP-A-3-291525.

However, although there is a device that always outputs abnormality information when the threshold value is exceeded, no method has been implemented in the past for determining whether or not to output abnormality information.

[0004]

In the method of always outputting the abnormality information when the threshold value is exceeded, the threshold value is once set in the abnormal mode in which the vibration gradually rises, such as when diagnosing equipment deterioration due to wear by the vibration method. Since abnormality information is output every time abnormality determination is made when the number of points exceeds the limit, there is a problem in that an online system with a large number of measurement points causes excessive detection, which imposes a load on checking information and causes a check error.

In order to solve the above problem, if the threshold value is increased, there is a risk that the abnormality will be overlooked, and if the number of times of abnormality determination is reduced, there is a possibility that a sudden abnormality cannot be detected. An object of the present invention is to provide a method of outputting abnormality information in an online facility diagnosis system that solves the above problems.

[0006]

The present invention solves the above-mentioned problems and is applied to a method of outputting abnormality information in an online facility diagnosis system by the vibration method, and the following method is adopted. That is, each measured value a _n (n = 1, 2,
Is output as abnormality information when the abnormal value a _i determined by comparing (i) with a predetermined threshold value satisfies the following expression, an abnormality information output method in an online facility diagnosis system.

[0007] Here, a _i is the abnormal value of the current measurement, and a _ip and a _iq are the abnormal values of the previous and the last-previous measurements (p, q = 1, 2 ..., q> p).
When there is no abnormal value, when the abnormal value is 1 point or a
_{If ip} −a _iq ≦ 0, set a _ip −a _iq = 0.

[0008]

The flow chart of the present invention is shown in FIG. Threshold A
Is set, and then the measured value a _n (n = 1, 2 ... i)
Enter When A> a _n , there is no abnormality, so a _n is not an abnormal value. However, A <a _n Dearuijochinouchi,zenkainoijochioa _i-1 ,Zenzenkainoijochioa _i-2 Tosurutoki, a _i> a _ip, a _iq and, {(a _{i -a ip) / (a ip -a} iq)}> 1 is determined to be abnormal value to be output an alarm to a _i satisfying were to output an alarm only at this time. No outliers
When the abnormal value is 1 point or when a _ip −a _iq ≦ 0
Then, a _ip −a _iq = 0.

According to the present invention, whether to issue an abnormal alarm or output information in this manner is determined in consideration of the comparison with the previous measured value and the rate of increase of the measured value. Therefore, even if the threshold value is exceeded due to the abnormality determination, the abnormality information is not output when it is lower than the previous measurement value or when the increase rate of the measurement value is smaller than the previous value.
The number of information to be output is about 1/3, the load required for checking information can be reduced, and check mistakes can be prevented.

[0010]

1 is a block diagram of a system in which the present invention can be preferably implemented. In this system, the data collected by the route of sensor 1 → channel switch 2 → A / D converter 3 → average value calculation circuit 4 → personal computer 5 is trend-managed,
Once on the personal computer 5, the average value data of Hr is compared with the threshold value, and when it is judged as an abnormal value, the frequency analysis data is obtained through the route of sensor 1 → channel switch 2 → frequency analysis device 7 → personal computer 5. The data is automatically input to the personal computer 5, the automatic diagnostic program in the personal computer is started, and the abnormality content is automatically output to the printer 6.

In this embodiment, the logic of the flow chart of FIG. 1 is added to a program for determining abnormality in a personal computer. FIG. 3 is a transition graph of the vibration acceleration value of the online vibration diagnosis system showing the embodiment of the present invention, and shows the relationship between the threshold value of a predetermined measurement point and the measurement value. This system makes an abnormality determination once a hour, and the number of measurement points is 300.

By introducing the above-mentioned alarm output determination condition, the abnormality information, which was 100 / day in the entire system before the introduction, was reduced to 10 / day. Regarding the measurement points shown in FIG. 3, the abnormal information of 23 times / day was 3 times / day.

[0013]

As described above, according to the present invention, the abnormality information output of the online facility diagnosis system is performed in consideration of the comparison with the previous measurement value and the rate of increase of the measurement value. The property has improved.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an abnormality determination output method of the present invention.

FIG. 2 is a system block diagram in which the present invention can be preferably implemented.

FIG. 3 is a transition graph of vibration acceleration.

[Explanation of symbols]

1 sensor 2-channel switcher 3 A / D converter 4 average value calculating circuit 5 PC 6 printer 7 frequency analyzer a~x vibration measurement point A: threshold _{a n (n = 1,2 ... i} ): measured value a _i , A _ip , a _iq : Abnormal value whose measured value exceeds the threshold value ◯: Measuring point that does not output abnormal information ●: Measuring point that outputs abnormal information

Claims (1)

(57) [Claims] 1. In a method of outputting abnormality information in an online facility diagnosis system by the vibration method, each measured value a _n
When the abnormal value a _i determined by comparing (n = 1, 2 ... i) with a predetermined threshold value satisfies the following formula, this is output as abnormal information. output method. Here, a _i is the abnormal value of the current measurement, and a _ip and a _iq are the abnormal values of the previous and the last-previous measurements (p, q = 1, 2 ..., q> p).
When there is no abnormal value, when the abnormal value is 1 point or a
_{If ip} −a _iq ≦ 0, set a _ip −a _iq = 0.