JPH06104803A - Data collection device utililing power distribution line - Google Patents

Abstract

PURPOSE:To allow the data collection device collecting metering data through power distribution line carrier from a low voltage power distribution line via a distribution carrier MODEM circuit in the automatic metering system and storing the data to a metering data storage memory to collect data efficiently or with high reliability while avoiding the effect of noise. CONSTITUTION:A data collection device 2 measures a noise level of a low voltage power distribution line 6 for each unit time via a level measurement circuit 15 and stored in a measurement data storage memory 17. A center equipment reads measurement data via a communication line 5 and a communication interface 13 and give a command to the data collection device 2 by selecting a time band receiving a low noise level to allow the device 2 to collect data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data collecting device such as an automatic meter reading system by a distribution line conveying system which is a data communication system using a low voltage distribution line as a transmission line.
In the drawings below, the same reference numerals indicate the same or corresponding parts.

[0002]

2. Description of the Related Art A distribution line conveying system using a low voltage distribution line is
As described below, a line-to-line system that uses transmission lines as the transmission line,
There is an earth return method that uses a transmission line between the common ground line and the earth.
FIG. 3 is a configuration diagram for explaining the line-to-line distribution line transportation. In this line-to-line system, the data collection device 2 and the transmission terminal device 3 are connected between two lines of the low-voltage distribution line 6, and AC100V
Communication is performed by superimposing a signal on. In the line system, the communicable range is divided for each system of the transformer 11.

FIG. 4 is a block diagram for explaining distribution line transportation of the earth return method. In this ground return method, one line of the data collection device 2 and the transmission terminal 3 is connected to the common ground line 6
Connect to a and connect the other wire to ground 12 to form a signal loop. Since the common ground wire 6a is connected in a wide range, it is possible to communicate across a plurality of systems.

FIG. 5 is a block diagram of an automatic meter-reading system for meter-reading a watt-hour meter as an example of a system for collecting data by carrying the distribution line. In the figure, 1 is a center device which is a higher-level device of the data collecting device 2, and 5 is a communication line connecting the data collecting device 2 and the center device 1. Reference numeral 9 is a customer who is supplied with electric power to the indoor wiring 8 by the low-voltage distribution line 6, and reads the measured value (meter reading value) of the watt-hour meter 4 and the watt-hour meter 4 that respectively measure the amount of electric power supplied, and a data collection device. It is provided with the above-mentioned transmission terminal device 3 for transmitting to No. 2. 7
Is a communication line connecting the transmission terminal 3 and the watt hour meter 4.

FIG. 6 is a sequence diagram showing the operation of this automatic meter reading system. Next, FIG. 6 will be described with reference to FIG. Note that S1 to S3 indicate steps in FIG. The center device 1 transmits a collection command to the data collection device 2 (S1). The data collection device 2 sequentially communicates with the watt-hour meter 4 via each transmission terminal device 3 to collect the meter reading value of the watt-hour meter 4 (S2). This operation is performed for all the consumers 9 managed by the data collection device 2. The center device 1 determines the time T2 for reading all the customers 9 from the time T1 for reading one customer 9, waits for T2 hours or more, and then performs communication with the data collecting device 2 again.
The meter reading values collected by the data collection device 2 are received (S
3).

[0006]

[Problems to be Solved by the Invention]

(1) The noise level of the distribution line changes from moment to moment depending on the load condition of the customer connected to the distribution line. Therefore, depending on the load condition, the noise level is high and the S / N ratio is high.
There are times when the ratio cannot be secured. In addition, the noise level of the distribution line has different characteristics depending on the region due to the difference in the power consumption pattern of the customer.

Therefore, in order to improve the reliability of communication by the distribution line carrying method, the noise characteristic of the distribution line is measured for each area where communication is performed, and the noise level of the distribution line is low from the obtained noise characteristic. It is necessary to select a time zone and communicate during that time zone. (2) When a plurality of data collection devices exist in the area connected by the common ground line in distribution line transportation by the earth return method, adjacent data collection devices when one data collection device performs communication The signal leaks to the meter reading area.

Therefore, the present system requires the following measures. Signal leakage to other meter-reading areas is actually measured, and a data collection device that can communicate at the same time is determined. The center device manages so that multiple data collection devices do not communicate simultaneously.

Only when the distances between the data collection devices are sufficiently large and it can be determined that the mutual communication is not affected, the simultaneous communication is performed. So this invention
By automatically measuring the noise characteristics of the distribution line and determining the state where the noise level of the distribution line is low and which is most suitable for communication, the reliability of data communication by the distribution line transportation method is improved, and the earth return method In the above, it is an object to provide a data collection device by distribution line transportation that can determine a data collection device that can communicate at the same time and can perform efficient data collection.

[0010]

In order to solve the above-mentioned problems, a data collecting apparatus according to claim 1 uses a distribution line carrier (using a low-voltage distribution line 6 or the like) (via a distribution modem circuit 14 or the like). ) A device (2 or the like) for collecting (and storing in the meter reading data storage memory 16 or the like) the meter reading data and the like (means for measuring and storing the noise level of the distribution line every unit time (level measuring circuit 15, Measurement data storage memory 17,
CPU 18 etc.).

According to a second aspect of the data collecting apparatus, the data collecting apparatus according to the first aspect is based on the recorded measurement data of the noise level (by a command from the center apparatus 1 or a collection time setting, etc.). ) The above-mentioned data collection is performed during the time when the noise level is the lowest. According to the data collecting device of claim 3,
Alternatively, the data collecting apparatus according to claim 2 is for carrying the distribution line of the earth return method (using the common ground wire 6a, the earth 12, etc.), and based on the recorded noise level measurement data. Then, the data collection is performed at the same time as a predetermined other data collection device having less mutual interference of data transmission (by a command from the center device 1 or the like).

[0012]

The data collecting device is provided with the level measuring circuit for measuring the noise level of the distribution line, and the noise level is measured and stored. Therefore, it is possible to know the noise characteristic of the distribution line for each unit time from the noise level measurement data collected by this level measuring circuit. From this noise characteristic, the time zone in which the noise level becomes the minimum is determined, and the determined time By performing communication in the band, the reliability of transmission can be improved.

Further, in the earth return method, when one data collecting device is communicating, the noise level is measured by another data collecting device, so that a signal leaks to another area. Can be measured, and if the range where signal leakage does not affect communication is analyzed from this measurement data,
At the same time, it is possible to determine a data collection device with which communication is possible.

[0014]

Embodiments Embodiments of the present invention will be described below mainly with reference to FIGS. 1 and 2. FIG. 1 is a block diagram of a data collection device as an embodiment of the present invention. This collection device 2 communicates with a center device 1 via a communication circuit 5 (the interface is also abbreviated as I / F). 1
3, the transmission terminal device 3 in the distribution line transportation via the low-voltage distribution line 6
A portable modem circuit 14 for communicating with the transmission terminal 3, a meter reading data storage memory 16 for storing the meter reading data collected by the communication with the transmission terminal 3, a level measuring circuit 15 for measuring the noise level of the low voltage distribution line, and this level Measurement data storage memory 1 for storing the measurement data obtained by the measurement circuit 15
7. A CPU 18 that controls the entire system.

FIG. 2 shows a shared ground line 6a and a data collection device 2.
3 shows an example of the connection state of FIG. The data collection device 2 (2a to 2g) is connected to the common ground wire 6a. The data collecting devices 2a to 2g are provided in the meter reading area 19a, respectively.
Data collection will be performed by distribution line transportation by the earth return method at ~ 19g. Next, the operation of FIG. 1 will be described with reference to the system configuration diagram of FIG.

The data collecting device 2 measures the noise level of the low-voltage distribution line 6 by the level measuring circuit 15 every unit time,
The data for 24 hours is stored in the measurement data storage memory 17. The center device 1 communicates with the data collection device 2 via the communication line 5, and receives the measurement data stored in the measurement data storage memory 17 from the data collection device 2.
Then, the noise characteristic of the low-voltage distribution line 6 can be known from the received measurement data. Therefore, if a time zone in which the noise is minimized is selected from the noise characteristics and a command is sent from the center device 1 so that the data collection device 2 collects data at that time, data collection is performed in a state where the low-voltage distribution line 6 has low noise. The device 2 can perform communication by distribution line transportation.

Further, in the line-to-line system distribution line transportation, there is no signal interference from other data collection devices that occur in the earth return system distribution line transportation, so that the data collection device 2 communicates with the center device 1. There is no need to manage the order in which
Therefore, by providing the data collecting device 2 with the function of discriminating the time zone with less noise, which is performed by the center device 1 in the above description, and setting the start time of the data collecting, the data collecting device 2 Determines the optimal time zone for communication,
The start time of data collection is set and the data collection device 2
Can automatically collect data.

Next, a case where the data collection device 2a carries out distribution line transportation by the earth return route will be described with reference to FIG. Data collection device 2a according to a command from the center device 1
Communicates with the transmission terminal device 3 existing in the meter reading area 19a. At this time, the data collecting devices 2b to 2g measure the noise level of the low voltage distribution line. The center device 1 is
After the communication of the data collection device 2a ends, the data collection device 2b
~ 2g collects the measurement data obtained by noise level measurement. The influence of the data collection device 2a can be determined from the measurement data being communicated by the data collection device 2a and the measurement data before and after it.

By changing the data collecting device for communication and performing the measurement, it is possible to analyze the interference between the data collecting devices in the entire area, and even if the communication is performed at the same time, the mutual communication is affected. The data collection device 2 that is not given can be identified. Then, in the subsequent data collection, the center device 1 can simultaneously issue a data collection command to the data collection devices that do not interfere with each other, and can perform efficient data collection.

[0020]

In order to obtain the noise characteristic of the low voltage distribution line, it is necessary to measure at least 24 hours. In the present invention, since the data collecting device measures the noise level of the low-voltage distribution line, the noise characteristic of the distribution line and the data collecting device in the distribution line transportation of the earth return method are based on the measured data. Signal interference can be analyzed. Therefore, it is not necessary to manually measure the noise level on the spot for 24 hours.

Further, the level measurement over a long period of time can be easily performed. Then, based on this noise level measurement data, select a time zone with a low noise level for highly reliable data collection, and in the case of the earth return method, make sure that data collection devices that do not interfere with each other collect data at the same time. The data collection can be made efficient.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a configuration diagram showing a connection configuration of a data collection device and a common ground line in the earth return method.

[Fig. 3] Configuration diagram for distribution line distribution of line system

[Fig. 4] Configuration diagram for earth return system distribution line transportation

[Fig. 5] System configuration diagram

FIG. 6 is a sequence diagram for explaining the data communication operation of FIG.

[Explanation of Codes] 1 center device 2 (2a to 2g) data collection device 3 transmission terminal 4 watt-hour meter 5 communication line 6 low-voltage distribution line 6a common ground line 7 communication line 8 indoor wiring 9 customer 10 high-voltage distribution line 11 Transformer 12 Earth 13 Communication interface 14 Delivery modem circuit 15 Level measurement circuit 16 Meter reading data storage memory 17 Measurement data storage memory 18 CPU 19 (19a-19g) Meter reading area

Claims (3)

[Claims] 1. A device for collecting meter-reading data or the like by carrying a distribution line, comprising means for measuring and storing a noise level of the distribution line every unit time and collecting the data by carrying the distribution line. apparatus. 2. The data collecting device according to claim 1, wherein the data collecting device collects the data based on the recorded measurement data of the noise level during a time period when the noise level becomes minimum. Characteristic data collection device by distribution line transportation. 3. The data collecting device according to claim 1 or 2 is for carrying a distribution line of a ground return system, and based on the recorded measurement data of the noise level, data transmission is performed. A data collecting apparatus for carrying a distribution line, which collects the data at the same time as a predetermined other data collecting apparatus having less mutual interference.