JP2008009658A - Communication terminal device and watt-hour meter incorporating the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control power consumption to a prescribed value or lower even when a communication module whose power consumption is uncertain is used. <P>SOLUTION: A communication terminal device for fetching data of the watt-hour meter and transmitting them to other devices via a communication network is provided with: a communication part for executing interface processing with the communication network; an operation part for executing transmission processing with other devices; a first power supply part for fetching power from the electricity meter and supplying it to the operation part; and a second power supply part for charging an electricity storage means with power supplied by the watt-hour meter or the first power supply part by a constant current circuit and supplying the charge current for the communication part via a constant voltage circuit. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  INDUSTRIAL APPLICABILITY The present invention relates to a communication terminal device capable of effectively using a capacitor and transmitting meter reading data to a remote server while suppressing power consumption and its peak value in remote meter reading by a packet communication terminal of a watt-hour meter About.

  In recent years, so-called remote meter reading, in which meter reading data is sent to a server through various communication lines from watt-hour meters installed in various places, has been performed from the viewpoint of business efficiency. (See Patent Documents 1 to 3.)

  Conventional remote meter reading is mainly based on a meter reading method using a no-ringing line of a communication carrier. However, in the metering on the no-ringing line, the dual-line system, that is, the method in which the customer's communication line is a no-ringing line contract and the remote examination and public communication are used together, the communication may be disconnected during the remote examination. . This is because public communication is given priority when remote meter reading and public communication are congested.

  On the other hand, if remote meter reading is performed on a dedicated line, the cost becomes high, and since the years have passed since the development period, there is a problem that the system itself is aging.

  For this reason, a remote meter reading system using a PHS system or via a mobile phone network has been considered. (For example, see Patent Documents 2 and 3).

  In order to make effective use of the PHS system, we have been developing a remote meter reading system using this system, but now we are using other communication networks in consideration of the widespread use of PHS systems and radio wave conditions. The advent of a remote meter reading system was desired.

In recent years, a packet communication network for mobile carriers has been established and there is a cost advantage. Therefore, it is considered to adopt a packet communication terminal incorporating a communication module provided by a mobile carrier for a remote meter reading system. Yes.
JP-A-2005-274203 JP 2004-252821 A JP 2002-329282 A

  By the way, the power source of the communication device or the like becomes a problem when the watt-hour meter performs remote meter reading. That is, it is difficult to secure the power supply for the apparatus outside, and when securing the necessary power supply from the watt hour meter, it is necessary to ensure the accuracy of the watt hour meter. The power factor is limited to 60% or more.

  In general, it is difficult to improve the power factor in a portion with low power consumption, and the communication module provided by each communication carrier occupies most of the power consumption of the actual packet communication terminal, and there are large uncertainties. .

  The present invention has been made in view of the above-described circumstances, and provides a communication terminal device and a watt hour meter capable of controlling power consumption to a predetermined value or less even when a communication module with uncertain power consumption is used. The purpose is to do.

  In order to achieve the above object, a communication terminal apparatus according to the present invention transmits data between a communication module section (hereinafter referred to as a communication section) that executes interface processing with a packet communication network and other circuits, for example, a host server. In addition, a portion for performing data processing when the watt hour meter is externally attached is separated, and a capacitor is connected to the communication unit side via a constant current circuit. The capacitor is charged during normal operation, and the power supply to the communication unit is forcibly cut off when power is insufficient.

  Specifically, the communication terminal device according to the present invention is a communication terminal device for capturing watt-hour meter data and transmitting the data to another device via a communication network. A communication unit that performs interface processing with a network, a calculation unit that performs interface processing with the other device, a first power supply unit that takes in power from a watt-hour meter and supplies power to the calculation unit, A second power supply unit that charges the power storage means with a constant current circuit with power supplied from a meter or the first power supply unit, and supplies the charging current to the communication unit through the constant voltage circuit; It is characterized by that.

  Preferably, the output voltage of the constant current means is monitored, and when the voltage becomes lower than a predetermined voltage, erroneous data is sent from the communication section by providing voltage monitoring means for stopping the supply of power to the communication section. It is possible to prevent this, and it is possible to prevent the power usage amount of the power supply for integrated power from being exceeded. This predetermined voltage is preferably set higher than the operating voltage of the communication unit.

  Furthermore, the communication terminal device according to the present invention is provided with a means for setting the transmission interval of the electric energy data in the arithmetic unit, and further, the change of the charging voltage of the power storage means for a predetermined time by an instruction from another device. Means for detecting and changing the transmission interval is provided.

In the present invention, by monitoring the voltage change, it is possible to change the transmission interval and prevent the voltage from becoming lower than the operating voltage of the communication unit.
Note that the communication terminal device described above can also be configured integrally with a watt-hour meter.

  According to the present invention, power consumption can be controlled to a predetermined value or less even when a communication unit with uncertain power consumption is used.

  FIG. 1 is an explanatory diagram when the integrated power data is collected by the communication terminal device 1 according to the present embodiment and transmitted to the remote PPS simultaneous amount support system 3 or the automatic meter reading system 4 device. Hereinafter, the automatic meter reading system 4 will be described as a representative.

  In this figure, the communication terminal device 1 periodically collects and stores accumulated power data from the display terminal 20. The automatic meter reading system 4 periodically issues a transfer request for accumulated power data to the communication terminal device 1. The transfer request sent from the automatic meter reading system 4 is received by the communication facility 2b of the communication company through the dedicated line and sent to the packet network 2a. This data is received by the communication terminal device 1. The automatic meter reading system 4 and the communication facility 2b may be connected via a general-purpose communication network such as the Internet.

  When receiving the transfer request, the communication terminal device 1 transmits the stored accumulated power data to the request destination. The data sent to the packet communication network 2a follows the reverse path and is sent to the automatic meter reading system 4.

  FIG. 2 is a functional block diagram of the communication terminal device 1. In this figure, a communication terminal device 1 includes an AC / DC converter 11 that converts alternating current into direct current, a display terminal communication circuit 12 that exchanges data with an external display terminal 20, and a three-terminal regulator 13 that converts a voltage level. , A calculation unit 14, a constant current circuit 15, a capacitor 16, a DC / DC converter 17, and a communication unit 18.

  Note that peak current suppression means 19 may be inserted on the input side of the AC / DC converter 11. This also has a power factor improving effect. As the capacitor, an electric double layer capacitor is suitable because of its capacity and noise response.

  Here, the display terminal 20 is an extension of functions such as storage area and day / night display for the watt-hour meter. Of course, the display terminal 20 may be connected to the watt-hour meter instead of the display terminal in the above configuration. Is possible. In the following description, a case where power amount data is collected by the display terminal 20 will be described.

  Electric power is supplied to the communication terminal device 1 from the watt-hour meter. That is, it becomes the same power source as the measurement target. For this reason, it is important to control so that instantaneous values such as power consumption and peak current do not exceed specified values.

  When this power (AC 100 V) is supplied to the AC / DC converter 11 of the communication terminal device 1, it is converted into a predetermined DC voltage and supplied to the display terminal communication circuit 12, the three-terminal regulator 13, and the constant current circuit 15. The

The display terminal communication circuit 12 uses this power to exchange data with one or more external display terminals (watt-hour meters) 20 by a method such as a current loop.
The three-terminal regulator 13 adjusts the operating voltage (for example, DC 5V) of the CPU and supplies it to the computing unit 14. The output current of the AC / DC converter 11 charges the capacitor 16 through the constant current circuit 15, and this charging current is converted into the operating voltage of the communication unit 18 through the DC / DC converter 17 and supplied. The

Next, the operation of the communication terminal apparatus 1 having the above configuration will be described.
(Data collection process)
The communication terminal device 1 inputs the integrated power data of the display terminal 20 via the display terminal communication circuit 12 and sends it to the calculation unit 14. The calculation unit 14 edits this data according to the transmission format of the automatic meter reading system 4.

  Then, according to the data transfer request from the automatic meter reading system 4, the edited data is transferred to the communication unit 18, and the communication unit 18 sends this data to the packet network 2a.

  The communication unit 18 stores in advance a program for executing a protocol for communicating with the communication facility 2b of the communication company through the packet network 2a.

  The integrated power data sent to the packet network 2a is sent to the communication facility 2b according to this protocol, and delivered to the automatic meter reading system 4 via a dedicated line.

(Voltage monitoring process)
Next, the charging voltage monitoring function of the capacitor 16 executed by the calculation unit 14 will be described with reference to FIG. Note that when the operating voltage of the DC / DC converter 17 is DC 4.5V to 7.5V, the monitoring voltage is within the operating range, and the first power supply to the communication unit 18 is started. Voltage level (DC 6.0 V) and a second voltage level (DC 4.5 V) for stopping power supply are set in advance. As the second voltage level, the lower limit value of the operation range of the DC / DC converter 17 is normally set. However, if necessary, a setting with a margin may be performed.

  The first voltage level needs to be set to a value with a sufficient margin so that it does not drop below the second voltage level due to the power consumption of at least one transmission.

  When the voltage monitoring means 21 of the calculation unit 14 takes in the charging voltage value, it first determines whether or not it is equal to or higher than the first voltage level (6.0 V) (S101). If the voltage level is equal to or higher than the first voltage level, the communication unit 18 is turned on (S102). Note that the voltage monitoring unit 21 may be provided independently of the calculation unit 14.

  On the other hand, if the charging voltage is lower than the first voltage level, the charging voltage is compared with the second voltage level (4.5 V) (S103). If the voltage level is equal to or higher than the second voltage level, the process returns to step 101 again. When the voltage level is lower than the second voltage level, the power supply of the communication unit 18 is turned off (S104).

  When the power supply to the communication unit 18 is turned off, the communication unit 18 stops and communication with the communication facility 2b of the communication company is interrupted. However, the operation of the calculation unit 14 continues, so the display terminal communication circuit 12 Since the collection of the integrated power data from the display terminal 20 is continued via the, the stored data can be transmitted when the voltage level next rises.

(Other examples)
Data in a predesignated mode is transmitted by polling from the automatic meter reading system 4. At this time, when a certain mode (for example, mode 1) is set, communication terminal apparatus 1 first transmits the voltage value of capacitor 16 and then transmits data of a predetermined length. Thereafter, the voltage value of the capacitor 16 is transmitted again. Note that the transmission data at this time may be predetermined pattern data or power amount data. The predetermined data is data that consumes a large amount of power during transmission in a bit string of 0 or 1, and is preferably a data length of the actual power amount or longer.

  When the automatic meter reading system 4 side receives these series of data, it calculates a voltage drop when the communication terminal device 1 transmits predetermined data. The relationship between the data length and the voltage drop is collected in advance and stored in a table on the automatic meter reading system 4 side.

  Next, when the automatic meter reading system 4 requests data from the communication terminal device 1, the automatic meter reading system 4 calculates the transmission interval from the charging time stored in advance based on the relationship between the voltage drop and the data length. The charging time may be calculated from the voltage change by transmitting the voltage value of the capacitor 16 again after a predetermined time has elapsed from the transmission of the predetermined data and the voltage value of the capacitor 16.

  As described above, according to the present embodiment, the calculation unit 14 and the communication unit 18 are configured independently, and the communication unit 18 is powered by the power source configured by the constant current circuit 15, the capacitor 16, and the DC / DC converter 17. Since the power is supplied, the capacitor 16 can cut the power consumption peak. Further, when the capacitor 16 becomes equal to or lower than the operating voltage of the DC / DC converter 17, the power supply to the communication unit 18 is stopped, while the operation of the calculation unit 14 is continued to collect the accumulated power data. Even when power is supplied from the inside of the power meter, it is possible to avoid a decrease in accuracy of the power meter due to overuse and to prevent data loss.

  In a host system such as an automatic meter reading system, a change in the collection interval (or collection timing) by detecting a change in the charging voltage of the capacitor 16 makes it possible to change the capacity of the capacitor due to a difference in data amount or power consumption of each communication unit. This adjustment is unnecessary, or if only coarse adjustment is performed, fine adjustment can be handled by changing the collection interval, so that optimum collection is possible. Note that the collection interval may be changed on the communication terminal device side instead of being determined by the host system.

  The present invention can be implemented with various modifications without departing from the scope of the invention. For example, in the above-described embodiment, the watt-hour meter and the communication terminal device are configured to be independent and the power amount data is collected in the communication terminal device. It is also possible to configure.

It is explanatory drawing of the automatic meter-reading method using the communication terminal device by embodiment of this invention. It is a block diagram of the communication terminal device of FIG. It is operation | movement explanatory drawing of the voltage monitoring means of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Communication terminal device 2b Communication equipment 3 PPS simultaneous same amount support system 4 Automatic meter-reading system 2a Packet network (communication network)
DESCRIPTION OF SYMBOLS 11 AC / DC converter 12 Display terminal communication circuit 13 3 terminal regulator 14 Operation part 15 Constant current circuit 16 Capacitor (electric storage means)
17 DC / DC converter (constant voltage circuit)
18 Communication Unit 19 Peak Current Suppression Unit 20 Display Terminal 21 Voltage Monitoring Unit

Claims (5)

A communication terminal device for capturing watt-hour meter data and transmitting it to another device via a communication network,
The communication terminal device includes a communication unit that performs interface processing with the communication network;
An arithmetic unit that executes transmission processing with the other device;
A first power supply unit that takes in the power from the watt-hour meter and supplies power to the calculation unit;
A second power supply unit that charges the power storage means by a constant current circuit with the electric power supplied from the watt hour meter or the first power supply unit, and supplies the charging current to the communication unit via the constant voltage circuit;
A communication terminal device comprising:   The communication terminal apparatus according to claim 1, further comprising a voltage monitoring unit that monitors a charging voltage of the power storage unit and stops supply of electric power to the communication unit when the charging voltage becomes equal to or lower than a predetermined voltage.   The communication terminal apparatus according to claim 2, wherein the calculation unit includes means for setting a transmission interval of power amount data.   The said calculating part is provided with the means to change the said transmission interval by detecting the change of the charging voltage of the said electrical storage means for the predetermined time by the instruction | command from said another apparatus. The communication terminal device described.   5. A watt-hour meter comprising the communication terminal device according to claim 1.

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