JPH08228387A - Plant data collection system - Google Patents

Abstract

PURPOSE: To secure the reliability according with data from each plant and to reduce the processing load of a host computer and that of a communication line in the remote monitor system. CONSTITUTION: A valid count value 6 and a valid count value initial value 7 for data from each plant are stored in a storage part 1 of a host computer 21 which controls a telemeter. The valid count value 6 is periodically counted down by a valid count value counting-down part 11 and is so initialized that it is equal to the valid count value initial value 7 when the latest data is collected to update a data value 5 in the storage part 1. When the valid count value 6 is counted down to a prescribed value or smaller, it is judged that data is old and the reliability is reduced, and a data transfer request is sent from a data collection part 14 to a corresponding telemeter slave station equipment through a communication control part 15 and a telemeter master station 22; and when a response is returned, a data value 4 is updated, and the valid count value 6 is initialized. If the response is not returned by some fault, the valid count value 6 is continuously counted down, and the data value 5 is regarded as abnormal at the time of counting-up.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a remote monitoring system, and more particularly to a telemeter slave station device for collecting plant data from a plant at a remote place and a telemeter master station for collecting plant data from the telemeter slave station device. The present invention relates to a plant data collection method including a device.

[0002]

2. Description of the Related Art Conventionally, the collection of plant data in a remote monitoring system is performed at intervals of several seconds for analog information (instantaneous value information) and 1 for counter information (integrated value information).
This is done by requesting data transfer from the host computer to the telemeter slave station device at intervals of about a minute and receiving the response. In addition to collecting data at fixed intervals, changes in plant status (changes in data values, changes in plant operation / shutdown, changes in switch on / off, etc.)
When this occurs, the telemeter slave station device updates the data collected by the host computer by transmitting only the data item whose state has changed.

Other conventional techniques include, for example, Japanese Patent Laid-Open No. 6
There is a method such as 0-244132 “Data collection method” which adjusts the data collection cycle by paying attention to the rate of change of plant data.

[0004]

In the conventional plant data collection method, regarding the data regarding the state change, if the state change information transmitted from the telemeter slave station device does not exist for a long time, does the state actually change? There is a problem that it is impossible to distinguish whether the telemeter slave station device has transmitted the state change information but has not reached the host computer due to some trouble.

Also, the analog information / counter information periodically collected from the host computer includes those that need to be collected in a short cycle and those that do not, because they fluctuate in a short cycle, and are usually the most common. There was no choice but to collect all data items according to the data items that fluctuate widely. As a result, the processing load on the host computer and the load on the communication line are increased.

Furthermore, in the data collection method in which the cycle of data collection is adjusted according to the rate of change of plant data, a data item that repeatedly fluctuates in a fine cycle is regarded as having no fluctuation when the fluctuation range is small. However, there was a problem that it was not always possible to collect data efficiently.

[0007]

In order to solve the above-mentioned problems, in the present invention, a collecting cycle is set for each plant data, and data is collected at the collecting cycle for each plant data. .

[0008]

The plant data includes status information (operation, stop, etc.) of various devices, analog information (instantaneous value information) input by current or voltage, counter information (integration information) input by pulse signal, etc. However, the collection cycle is set according to the nature of the plant data. Then, data is collected from the telemeter slave station at the set collection cycle. If data cannot be collected within the collection period, it can be considered that an abnormality has occurred in the telemeter slave station or communication path.

[0009]

The present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a plant data collection system of the present invention, in which each plant 25, 25, ...
The plant data from the telemeter slave station 24, 24, ...
And is sent to the telemeter master station 22. The operation of the telemeter master station 22 is controlled by the host computer 21 as a control means.

FIG. 2 is a block diagram showing the configuration of the host computer 21, and the host computer 21 is
A storage unit (memory) 1, a valid count value subtraction unit 11, a periodic activation generation unit 12, a calculation unit 13, a data collection unit 14, and a communication control unit 15 are provided.

In the data storage area of the storage unit 1, an address 2 which is a value assigned to each plant data, a data type 3 which represents the type of data, and a data which represents the latest data value collected from the plant A value 4, a data state 5, a valid count value 6, and a valid count value initial value 7 are stored. In the embodiment, the effective count value is 6,
The unit of the initial value 7 of the effective count value is seconds.

The computing unit 13 computes the physical data received from the telemeter master station 22, converts it into a logical data value, writes the value in the data value 4, and updates the data value 4 and counts the effective count. The value of the effective count value initial value 7 is written in the value 6.

The effective count value subtracting unit 11 receives the periodic activation from the periodic activation generating unit 12, and subtracts the effective count value 6 for every unit of the plant data by one unit (second).

The effective count value has the following three stages. Data values are valid and do not need to be collected. The data value is valid, but the time has passed since it was last updated and reliability is decreasing. Data collection is required at this point. Counted up and the data value is no longer valid. At this point, the data state becomes abnormal.

The effective count value subtracting unit 11 requests the data collecting unit 14 to collect data if there is a data item that has reached the above-mentioned stage. In addition, the data state of the data item that has reached the stage is abnormally changed.

The data collection unit 14 requests the telemeter master station device 22 via the communication control unit 15 to collect the plant data requested by the effective count value subtraction unit, and the request is made by the communication line 23 to the corresponding telemeter. It is transferred to the slave station device 24. The telemeter slave station device 24 returns the latest value of the designated data collected from the plant 25 and held in the device through the reverse route.

If there is a failure in this path and no data is returned to the host computer 21 within the specified time, the valid count value 6 continues to decrease, and finally the data state 5 becomes abnormal.

Next, the operation of the above embodiment will be described with reference to the flow charts of FIGS. FIG. 3 shows the operation of the effective count value subtraction unit 11, and the processing of steps 301 to 306 is periodically repeated. That is, first, the effective count value is subtracted (301), and it is determined whether the effective count value has become equal to or less than a predetermined value (302). The predetermined value is determined according to each plant data. A predetermined value may be set, or a ratio (for example, 10%) to the initial value of the effective count value may be set. If it is not less than the predetermined value, the process is terminated and the process proceeds to the next cycle. If it is not more than the predetermined value, it is checked whether the data collection unit 14 is requested to collect data (303), and if not, it is requested (30).
4). If data collection is requested, it is then determined whether the effective count value 6 is counted up (becomes 0) (30
5) If the count is not up, the process ends and the next cycle starts. If it is, the data status 5 of the storage unit 1 is “abnormal”.
Is written (306). Based on the record of this "abnormality", for example, it can be displayed on a display means such as a CRT, or some kind of warning can be given.

The flowchart of FIG. 4 shows the operation of the arithmetic unit 13 when the latest data is sent in response to the data collection request (step 304). First, the effective count value 6 is initialized (401). ). That is, the value set in the effective count value initial value 7 is set as the effective count value. Next, check whether the data status 5 is "abnormal", and if it is "abnormal", set it to "normal" (40
3) Finish.

The effective count value initial value 7 is determined by the degree of fluctuation of the data value in the plant. In the storage unit 1 of FIG. 2, the alarm status information at the address 1-1-1-1 has a low frequency of status change but is alarm status information and has a high priority. Therefore, the alarm status information is collected once every 600 seconds. It is set. The address 1-1-2-2 is the status information other than the alarm of the device, the frequency of status change is relatively low, and the importance thereof is not high, so that it is set to 1800 seconds. Since the address 1-1-3-3 has a high variation frequency even in the analog information, it is collected in a short cycle of 15 seconds. Even with the same analog information, 1-1-3
-4 is an item with little fluctuation, and sufficient reliability can be maintained by collecting data at intervals of 60 seconds. Address 1-1-4-5
Is counter information, which is normally set to 300 seconds in order to guarantee the minimum reliability because the data is updated by the state change from the plant side.

[0021]

As described above, according to the plant data collection method of the present invention, it is effective according to the characteristics such as the frequency of fluctuation of each plant data and the content of the data (alarm or status, high or low importance, etc.). By determining the initial count value, it is possible to collect data in the minimum necessary period and collect / hold the latest value with sufficient reliability. As a result, it is possible to reduce the processing load of the arithmetic unit that repeatedly performs particularly complicated processing for each data and the load of the communication line.

[Brief description of drawings]

FIG. 1 is a block diagram showing the overall configuration of an embodiment of a plant data collection system of the present invention.

FIG. 2 is a block diagram showing the configuration of the host computer shown in FIG.

FIG. 3 is a flowchart showing the operation of the host computer shown in FIG.

FIG. 4 is a flowchart showing the operation of the host computer shown in FIG.

[Explanation of symbols]

 1 recording section 2 address assigned for each data 3 data type indicating the type of data 4 data value 5 data state 6 valid count value 7 valid count value initial value 11 valid count value subtraction section 12 cycle start generation section 13 arithmetic section 14 data Collection unit 15 Communication control unit 21 Host computer 22 Telemeter master station device 23 Communication line 24 Telemeter slave station device 25 Plant

Claims (3)

[Claims] 1. A plant data collection method comprising a telemeter slave station device that collects plant data from a plant at a remote location and a telemeter master station device that aggregates plant data from this telemeter slave station device, The plant data is composed of a plurality of data, a collection cycle is set for each plant data, and a control means is provided for controlling the telemeter master station so as to collect the data at the collection cycle for each plant data. Frant data collection method. 2. The control means, setting means for setting a count value initial value indicating the collection period, subtraction means for subtracting the count value, and the telemeter parent when the count value becomes a predetermined value or less. The plant data collection method according to claim 1, further comprising a data collection unit that instructs the station to collect data. 3. The plant data collection method according to claim 2, further comprising means for attaching a predetermined record to the plant data when the data cannot be collected before the count value is counted up.