JP2019004234A - Power information collection system and communication control method - Google Patents

Abstract

To provide a power information collection system and a communication control method capable of preventing the number of slave units managed by a master unit from being excessive.SOLUTION: A power information collection system includes a slave device for acquiring power information, and a plurality of master devices. The slave device communicates with the master device belonging to the same network to be a transmission destination of the power information via a power line by using identification information that can specify the master device. The master device receives notification of the identification information during use from one or more other master devices, and sets the identification information that does not overlap the one or more pieces of identification information receiving the notification as the own identification information. The slave device has a storage region which can store information in a nonvolatile manner, and first stores the identification information of the master device to be a transmission destination of the power information as the identification information of the master device to be a transmission destination of the power information in the storage region in a state where the identification information is not stored in the storage region.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a power information collection system and a communication control method.

  2. Description of the Related Art In recent years, a power information communication system has been developed that measures the amount of power consumed at home and at the workplace and transmits it to a server such as an electric power company for the purpose of power saving. For example, Patent Document 1 (Japanese Patent Laid-Open No. 2006-67557) discloses the following technique.

  That is, a communication route construction method constructs a communication route between a parent communication terminal and a child communication terminal in a communication network including a parent communication terminal and a plurality of child communication terminals, and the communication terminal A communication quality notification step of transmitting a notification communication packet including communication quality information indicating communication quality in a communication route between the own communication terminal and the parent communication terminal to the communication network by broadcast communication; and communication of the child When the terminal receives the notification communication packet, the communication quality from the communication terminal of the transmission source that has transmitted the notification communication packet to the communication terminal is acquired, and the transmission source that has transmitted the notification communication packet from the communication terminal A communication quality acquisition step of acquiring communication quality to the other communication terminal, and a child communication terminal receiving the notification communication packet in the communication quality acquisition step. The communication quality between the parent communication terminal and the own communication terminal is calculated based on the two-way communication quality and the communication quality information included in the received notification communication packet. A communication route construction step of constructing a communication route between the parent communication terminal and the own communication terminal only when the communication quality satisfies a predetermined condition.

JP 2006-67557 A

G3-PLC (Registered Trademark) Alliance, “Narrowband OFDM PLC specifications for G3-PLC networks”, G3-PLC Alliance, October 2014 IEEE Computer Society, "Standard for Information technology-Telecommunications and information exchange between systems-Local and metropolitan area networks-Specific requirements Part 15.4: Wireless Medium Access Control (MAC) and Physical Layer (PHY) Specifications for Low-Rate Wireless Personal Area Networks (WPANs) ", IEEE Std 802.15.4 (R) -200 (Revision of IEEE Std 802.15.4-2003), IEEE, 9 May 8, 2006

  In a communication system including a parent device and a child device such as a communication network described in Patent Document 1, the number of child devices managed by the parent device may become excessive. In such a case, the communication frequency between the parent device and the child device increases, and the packet loss rate may increase. There is a need for technology that can prevent the number of slave units managed by the master unit from becoming excessive.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a power information collection system and a communication control method capable of preventing an excessive number of slave units managed by a master unit. Is to provide.

  (1) In order to solve the above-described problem, a power information collection system according to an aspect of the present invention includes a child device that acquires power information and a plurality of parent devices, and the child devices belong to the same network. The parent device communicates with the parent device that is the transmission destination of the power information via a power line using identification information that can identify the parent device, and the parent device notifies the identification information that is being used. Is received from one or more of the parent devices, and the identification information that does not overlap with the one or more of the identification information received is set as the identification information of itself, and the child device stores the information in a non-volatile manner. In the state where the storage information is stored in the storage area and the identification information is not stored in the storage area, the identification information of the parent device that is the transmission destination of the power information first is transmitted as the transmission of the power information. Destination and everything Storing in the storage area as the identification information of the parent device.

  (6) In order to solve the above-described problem, a communication control method according to an aspect of the present invention is a communication control method in a power information collection system including a child device that acquires power information and a plurality of parent devices. The child device has a storage area in which information can be stored in a nonvolatile manner, and can identify the parent device that is the parent device belonging to the same network and is the transmission destination of the power information. Communicating via a power line using identification information, the parent device receives notification of the identification information being used from one or more other parent devices, and the one or more identification information received The identification information that does not overlap is set as the identification information of itself, and the child device is the first transmission destination of the power information in a state where the identification information is not stored in the storage area The identification information of Kioya apparatus, and a step of storing in the storage area as the identification information of the parent device to be a transmission destination of the power information.

  The present invention can be realized not only as a power information collection system including such a characteristic processing unit, but also as a semiconductor integrated circuit that realizes part or all of the power information collection system.

  According to the present invention, it is possible to prevent the number of slave units managed by the master unit from becoming excessive.

FIG. 1 is a diagram showing a configuration of a power information collection system according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of each device and wiring state in the power information collection system according to the embodiment of the present invention. FIG. 3 is a diagram illustrating an example of a network topology in the power information collection system according to the embodiment of the present invention. FIG. 4 is a diagram showing an example of a MAC frame used in the power information collection system according to the embodiment of the present invention. FIG. 5 is a diagram illustrating an example of a sequence when the parent device sets PAN_ID in the power information collection system according to the embodiment of the present invention. FIG. 6 is a diagram illustrating an example of a sequence when a child device performs an entry process in the power information collection system according to the embodiment of the present invention. FIG. 7 is a diagram illustrating an example of a sequence when the child device performs the entry process again in the power information collection system according to the embodiment of the present invention. FIG. 8 is a diagram showing an example of a sequence when the parent device stops operating in the power information collection system according to the embodiment of the present invention. FIG. 9 is a diagram showing an example of a sequence when the parent device stops operating in the power information collection system according to the embodiment of the present invention. FIG. 10 is a diagram showing an example of a sequence when the parent device stops operating in the power information collection system according to the embodiment of the present invention. FIG. 11 is a diagram showing an example of a sequence when the parent device stops operating in the power information collection system according to the embodiment of the present invention.

  First, the contents of the embodiment of the present invention will be listed and described.

  (1) A power information collection system according to an embodiment of the present invention includes a child device that acquires power information and a plurality of parent devices, wherein the child device is the parent device belonging to the same network, and The parent device that is the transmission destination of the power information communicates with the parent device using the identification information that can identify the parent device, and the parent device notifies other one or more notifications of the identification information in use The identification information that does not overlap with one or more of the identification information received from the parent device is set as the identification information of the self device, and the child device has a storage area in which information can be stored in a nonvolatile manner. The parent device that should be the transmission destination of the power information with the identification information of the parent device that first becomes the transmission destination of the power information in a state where the identification information is not stored in the storage area And the identification information Storing in the storage area Te.

  As described above, in a state where the identification information is not stored in the storage area, the identification information of the parent apparatus that is the transmission destination of the power information first is used as the identification information of the parent apparatus that should be the transmission destination of the power information. With this configuration, the child device, for example, when the power of the child device is turned off and removed from the management of the parent device and then turned on again, based on the identification information in the storage area, Since the parent device that should be the transmission destination can be recognized, it is possible to prevent the transmission destination of the power information from being erroneously set as another parent device. In addition, for example, since the parent device stopped operating when the power was turned on again, even if the child device accidentally enters the management of another parent device, the child device does not have the identification information in the storage area. Based on the above, it is possible to recognize that the destination of the power information is incorrect, so that the user can withdraw from the management of the other parent device, or can be withdrawn from the management of the other parent device according to the instructions of the other device. You can do it. As a result, it is possible to prevent the number of slave units managed by the master unit from becoming excessive. For example, it is possible to prevent an increase in the packet loss rate.

  (2) Preferably, in a case where the child device performs an entry process for starting communication with the parent device as a transmission destination of the power information again, the parent of the target identification information that is the stored identification information The entry process is preferentially performed on the apparatus.

  With such a configuration, when the entry process is performed again, it is possible to reduce the possibility that the transmission destination of the power information is mistaken for a parent device different from the parent device of the target identification device.

  (3) More preferably, the child device cannot recognize the parent device of the target identification information in the case of performing entry processing for starting communication with the parent device as a transmission destination of the power information again. The entry process is performed on the other parent device selected based on the communication quality with itself.

  With such a configuration, even in a situation where power information cannot be transmitted to the parent device of the target identification information, power information can be transmitted to another parent device capable of communicating with higher quality. It is possible to avoid a situation where transmission is not possible.

  (4) Preferably, in the state where the child device sets the parent device of the identification information different from the target identification information which is the stored identification information as the transmission destination of the power information, If the target parent device is found and the target parent device is found, the process of switching the transmission destination of the power information to the target parent device is performed.

  With this configuration, even if the child device mistakenly sets the transmission destination of the power information to the parent device having identification information different from the target identification information, the transmission destination of the power information is detected as soon as the target parent device is discovered. Can be switched to the target parent device. As a result, it is possible to prevent the child device from continuing to transmit power information to an erroneous transmission destination.

  (5) Preferably, after the child device performs an entry process for starting communication with the parent device as the transmission destination of the power information again, the child device is the transmission destination of the power information. When designation of different identification information is received from a predetermined device, a process of switching the transmission destination of the power information to the parent device of the designated identification information is performed.

  With such a configuration, when the child device performs the entry process again, for example, even when another parent device different from the parent device of the identification information in the storage area is used as the transmission destination of the power information, According to an instruction from the device, the transmission destination of the power information can be switched to the parent device of the identification information in the storage area. Thereby, it is possible to prevent the child device from continuing to transmit the power information to another parent device.

  (6) A communication control method according to an embodiment of the present invention is a communication control method in a power information collection system including a slave device that acquires power information and a plurality of master devices. The parent device belonging to the same network and serving as the transmission destination of the power information, and using the identification information that can identify the parent device via the power line The parent device receives notification of the identification information being used from one or more other parent devices, and self-identifies the identification information that does not overlap with the received one or more identification information. The identification information of the parent device that is the first transmission destination of the power information in a state where the identification information is not stored in the storage area, As the identification information of the parent device to be a transmission destination of the serial power information and a step of storing in the storage area.

  As described above, in a state where the identification information is not stored in the storage area, the identification information of the parent apparatus that is the transmission destination of the power information first is used as the identification information of the parent apparatus that should be the transmission destination of the power information. With this configuration, the child device, for example, when the power of the child device is turned off and removed from the management of the parent device and then turned on again, based on the identification information in the storage area, Since the parent device that should be the transmission destination can be recognized, it is possible to prevent the transmission destination of the power information from being erroneously set as another parent device. In addition, for example, since the parent device stopped operating when the power was turned on again, even if the child device accidentally enters the management of another parent device, the child device does not have the identification information in the storage area. Based on the above, it is possible to recognize that the destination of the power information is incorrect, so that the user can withdraw from the management of the other parent device, or can be withdrawn from the management of the other parent device according to the instructions of the other device. You can do it. As a result, it is possible to prevent the number of slave units managed by the master unit from becoming excessive. For example, it is possible to prevent an increase in the packet loss rate.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated. Moreover, you may combine arbitrarily at least one part of embodiment described below.

[Configuration of power information collection system]
FIG. 1 is a diagram showing a configuration of a power information collection system according to an embodiment of the present invention.

  With reference to FIG. 1, the power information collection system 301 includes a plurality of smart meters 101, a plurality of concentrators 102, and a server 103. The server 103 is a head end, for example.

  The power information collection system 301 is not limited to a configuration including a plurality of smart meters 101, and may be configured to include a single smart meter 101. Further, the power information collection system 301 is not limited to a configuration including one server 103, and may be configured to include a plurality of servers 103.

  The power information collection system 301 is used, for example, in the apartment house 151. Each smart meter 101 is connected to the concentrator 102 via the power line 161. Specifically, for example, a plurality of systems of power lines 161 are arranged in the vertical direction of the upper and lower floors in the apartment house 151, and the smart meter 101 is connected to each floor.

  The smart meter 101 and the concentrator 102 exchange various information by power line communication using the power line 161, for example.

  Smart meter 101 is a slave unit in power line communication, and concentrator 102 is a master unit in power line communication. Hereinafter, the smart meter 101 and the concentrator 102 are also referred to as a child device 101 and a parent device 102, respectively.

  The slave device 101 is a power meter with a communication function. The slave device 101 periodically acquires, for example, power information indicating power consumed in a measurement target home or office, and transmits the acquired power information to the parent device 102.

  In addition, the child device 101 can communicate with the parent device 102 via another child device 101. That is, the child device 101 has a function of relaying communication between other child devices 101 and the parent device 102.

  Specifically, the child device 101 may directly transmit the acquired power information to the parent device 102 without passing through the other child device 101, and the acquired power information may be transmitted to one or more other child devices. In some cases, the data is transmitted to the parent device 102 via the device 101.

  The parent device 102 and the server 103 exchange various information via the Internet 10 by wired communication or wireless communication.

  The parent device 102 receives power information from each child device 101. The parent device 102 receives power information from each child device 101 and aggregates the received power information and transmits it to the server 103 or transmits the received power information to the server 103 individually.

  For example, the server 103 transmits power charge information to the parent device 102. When the parent device 102 receives the power charge information from the server 103, the parent device 102 transmits the received power charge information to the child device 101.

  When the child device 101 receives the power charge information from the parent device 102, the child device 101 transmits the received power charge information to another device such as a non-illustrated HEMS (Home Energy Management System).

  For example, Non-Patent Document 1 (G3-PLC Alliance, “Narrowband OFDM PLC specifications for G3-PLC networks”, G3-PLC Alliance, 2014) communicates between the parent device 102 and the child device 101. In October).

  Further, for example, information transmitted / received between the child device 101, the parent device 102, and the server 103 is encrypted and decrypted according to a predetermined method.

  FIG. 2 is a diagram illustrating an example of each device and wiring state in the power information collection system according to the embodiment of the present invention. In FIG. 2, three systems of power lines 161 in the apartment house 151, in this example, power lines 161A, 161B, and 161C are representatively shown.

  Referring to FIG. 2, for example, 6.6 kV three-phase AC power is supplied from the power system 171 to the apartment house 151. The AC power from the power system 171 is converted into a 200-V single-phase three-wire AC power by, for example, transformers 104A, 104B, and 104C and supplied to each floor.

  The power line 161A is connected to the transformer 104A, the parent device 102A that is the parent device 102, and the child devices 101C and 101D that are the child devices 101. The power line 161B is connected to the transformer 104B, the parent device 102B that is the parent device 102, and the child devices 101A and 101B that are the child devices 101. The power line 161C is connected to the transformer 104C, the parent device 102C that is the parent device 102, and the child devices 101E and 101F that are the child devices 101.

  The power information collection system 301 is not limited to a configuration including the parent devices 102A, 102B, and 102C, and may be configured to include two or four or more parent devices 102. Hereinafter, each of the transformers 104A, 104B, and 104C is also referred to as a transformer 104.

[Network topology]
FIG. 3 is a diagram illustrating an example of a network topology in the power information collection system according to the embodiment of the present invention.

  Referring to FIG. 3, parent device 102 and child device 101 have, for example, a PAN_ID (Personal Area Network Identification) and a short address. The PAN_ID is an example of identification information that can identify the parent device 102.

  Each parent device 102 has a different PAN_ID. The short address of each parent device 102 is set to zero, for example.

  Further, the parent device 102 and the child device 101 have, for example, a 64-bit long address that is an ID in an EUI (Extended Unique ID) -64 format that is an identifier unique to the device. This long address is set, for example, when the apparatus is manufactured.

  For example, the parent device 102 manages one or more child devices 101 and exchanges authentication information, power information, and the like with the child devices 101 to be managed.

  The child device 101 establishes a communication connection with the parent device 102 that is a transmission destination of power information. Specifically, when the child device 101C is not under the control of the parent device 102, the child device 101C establishes a communication connection with the parent device 102A.

  In this case, the child device 101C directly exchanges authentication information, power information, and the like with the parent device 102A, for example.

  If the child device 101D is not under the control of the parent device 102, the child device 101D establishes a communication connection with the parent device 102A via the child device 101C.

  In this case, the child device 101D exchanges authentication information, power information, and the like with the parent device 102A via the child device 101C. That is, the child device 101C is a hop destination for relaying information exchanged between the parent device 102A and the child device 101D. The child device 101D may establish a communication connection with the parent device 102A without going through the child device 101C.

  The PAN_ID of the parent device 102A and the child devices 101C and 101D under the management of the parent device 102A is, for example, “0001”.

  In addition, each device having the same PAN_ID is assigned a short address which is a different identifier. Specifically, the short addresses of the slave devices 101C and 101D are non-zero values that do not overlap each other, for example, “3” and “4”, respectively. The addresses of the child devices 101C and 101D are given by the parent device 102A, for example.

  The parent device 102A and the child devices 101C and 101D form a PA (Personal Area) network NWA.

  Similarly, the parent device 102B manages the child devices 101A and 101B. The PAN_ID of the parent device 102B and the child devices 101A and 102B under the management of the parent device 102B is, for example, “0002”. The short addresses of the slave devices 101A and 101B are non-zero values that do not overlap each other, for example, “1” and “2”, respectively. The addresses of the child devices 101A and 101B are given by the parent device 102B, for example.

  The parent device 102B and the child devices 101A and 101B form a PA network NWB.

  The parent device 102C manages the child devices 101E and 101F. The PAN_ID of the parent device 102C and the child devices 101E and 102F is, for example, “0003”. The short addresses of the slave devices 101E and 101F are, for example, “1” and “2”, respectively. The addresses of the child devices 101E and 101F are given by the parent device 102C, for example.

  The parent device 102C and the child devices 101E and 101F form a PA network NWC.

  That is, it is possible to determine which PA network the parent apparatus 102 and the child apparatus 101 are connected to based on the PAN_ID.

[MAC frame]
FIG. 4 is a diagram showing an example of a MAC frame used in the power information collection system according to the embodiment of the present invention. FIG. 4 shows the format of a MAC frame in accordance with the G3-PLC standard described in Non-Patent Document 1.

  Referring to FIG. 4, MAC frame 71 includes a MAC header, a MAC payload, and a MAC footer.

  The MAC header includes, for example, “Segment control”, “Frame control”, “Sequence number”, “Destination PAN”, and “Destination address”. , “Source PAN”, “Source address”, and “Auxiliary security header” fields. These fields are 3 octets, 2 octets, 1 octet, 2 octets, 2 octets, 2 octets, 2 octets and 2 octets, respectively.

  In the “destination address” field, for example, the short address of the destination of the MAC frame 71 is stored. In the “source address” field, for example, the short address of the source of the MAC frame 71 is stored.

  Note that the MAC frame 71 may not include at least one of the fields of “destination PAN”, “destination address”, “source PAN”, “source address”, and “sub security header”.

  Further, the long address of the destination of the MAC frame 71 may be stored in the “destination address” field. Further, the long address of the transmission source of the MAC frame 71 may be stored in the “transmission source address” field.

[Flow of operation]
Each device in the power information collection system 301 includes a computer, and an arithmetic processing unit such as a CPU in the computer reads a program including a part or all of each step of the following sequence diagram or flowchart from a memory (not shown). Run. Each of the programs of the plurality of apparatuses can be installed from the outside. The programs of the plurality of apparatuses are distributed while being stored in a recording medium.

  FIG. 5 is a diagram illustrating an example of a sequence when the parent device sets PAN_ID in the power information collection system according to the embodiment of the present invention.

  Referring to FIG. 5, in a case where parent devices 102B and 102C have already built a PA network, for example, a situation is assumed in which the parent device 102A is turned on and the parent device 102A starts operating.

  First, the parent device 102A broadcasts a beacon request to search for another parent device 102 (step S102).

  More specifically, the parent apparatus 102A creates a beacon request in which “0xffff” and “0xffff” are stored in the “destination PAN” field and the “destination address” field in the MAC frame 71 shown in FIG. Hereinafter, a number starting with “0x” means that the number after “0x” is expressed in hexadecimal.

  Here, "0xffff" is stored in the field "Destination PAN" is non-patent document 2 (IEEE Computer Society, "Standard for Information technology-Telecommunications and information exchange between systems-Local and metropolitan area networks-Specific requirements Part 15 .4: Wireless Medium Access Control (MAC) and Physical Layer (PHY) Specialties for Low-Rate Wireless Personal Area Network rks (WPANs) ", IEEE Std 802.15.4-2006 (Revision of IEEE Std 802.15.4-2003), IEEE, September 8, 2006), defined as the value of broadcast PAN_ID It has been.

  Also, “0xffff” stored in the “destination address” field is defined as a broadcast short address value in the standard described in Non-Patent Document 2.

  Next, when receiving a beacon request from the parent device 102A, the parent device 102B creates a beacon that is a response to the received beacon request, and transmits the created beacon to the parent device 102A (step S104).

  In this beacon, the PAN_ID of the parent device 102B, that is, “0002”, and the short address of the parent device 102B, that is, zero are stored in the “source PAN” field and the “source address” field in the MAC frame 71, respectively.

  Next, upon receiving a beacon request from the parent device 102A, the parent device 102C creates a beacon that is a response to the received beacon request, and transmits the created beacon to the parent device 102A (step S106).

  In this beacon, the PAN_ID of the parent device 102C, that is, “0003”, and the short address of the parent device 102C, that is, zero are stored in the “source PAN” field and the “source address” field in the MAC frame 71, respectively.

  Next, the parent device 102A receives a notification of the PAN_ID being used from the plurality of other parent devices 102, and sets an ID that does not overlap with the received plurality of PAN_IDs as its own PAN_ID (step S108).

  Specifically, when receiving a beacon from parent devices 102B and 102C, parent device 102A sets PAN_ID based on each received beacon.

  More specifically, the parent device 102A acquires the PAN_ID and the short address from the beacon received from the parent device 102B, and recognizes that the acquired PAN_ID, that is, “0002” is in use.

  Further, the parent device 102A acquires the PAN_ID and the short address from the beacon received from the parent device 102C, and recognizes that the acquired PAN_ID, that is, “0003” is in use.

  Then, the parent device 102A, for example, randomly selects one address from the address space excluding “0002” and “0003” from the address space that can be used as the PAN_ID, and sets the selected address as its own PAN_ID. .

  In this example, the parent apparatus 102A sets “0001” as its own PAN_ID.

  Note that although the parent device 102A is configured to receive the PAN_ID from the parent devices 102B and 102C in step S104, the present invention is not limited to this. The parent device 102A may be configured to receive the PAN_ID from another one parent device 102 or other three or more parent devices 102. Then, the parent device 102A sets, as its own PAN_ID, an ID that does not overlap with one or more received PAN_IDs.

  Note that the order of steps S104 and S106 is not limited to the above, and the order may be changed.

  FIG. 6 is a diagram illustrating an example of a sequence when a child device performs an entry process in the power information collection system according to the embodiment of the present invention.

  Referring to FIG. 6, in a case where parent devices 102A, 102B, and 102C have already built a PA network, for example, a situation is assumed in which power to child device 101C is turned on and child device 101C starts operating. Further, the slave device 101C has a storage area capable of storing information in a nonvolatile manner, for example, a flash memory. Assume that this flash memory does not store a PAN_ID to be a transmission destination of power information.

  First, the child device 101C broadcasts a beacon request to search for the parent device 102 (step S202).

  Next, when receiving a beacon request from the child device 101C, the parent device 102C creates a beacon BC as a response to the received beacon request, and transmits the created beacon BC to the child device 101C (step S204).

  In the beacon BC, as described above, in the “source PAN” field and the “source address” field in the MAC frame 71, the PAN_ID of the parent device 102C, that is, “0003”, and the short address of the parent device 102C, that is, zero, respectively. Stored.

  Next, when receiving a beacon request from the child device 101C, the parent device 102B creates a beacon BB as a response to the received beacon request, and transmits the created beacon BB to the child device 101C (step S206).

  In the beacon BB, as described above, in the “source PAN” field and the “source address” field in the MAC frame 71, the PAN_ID of the parent device 102B, that is, “0002”, and the short address of the parent device 102B, that is, zero are respectively set. Stored.

  Next, when receiving a beacon request from the child device 101C, the parent device 102A creates a beacon BA as a response to the received beacon request and transmits the created beacon BA to the child device 101C (step S208).

  In the beacon BA, the PAN_ID of the parent device 102A, that is, “0001” and the short address of the parent device 102A, that is, zero are stored in the “source PAN” field and the “source address” field in the MAC frame 71, respectively.

  Next, when the child device 101C receives a beacon from the parent devices 102A, 102B, and 102C, the child device 101C performs selection processing for selecting the parent device 102 that is to be a communication destination based on each received beacon (step S210). .

  Specifically, the child device 101C selects, for example, the parent device 102 having the best communication quality with itself, in this example, the parent device 102A, as the parent device 102 that the self device should communicate with.

  Next, the child device 101C performs entry processing for starting communication with the parent device 102A that is the transmission destination of the power information (step S212).

  More specifically, the child device 101C communicates with the parent device 102 that belongs to the same PA network and is the transmission destination of power information via the power line 161 using the PAN_ID of the parent device 102.

  Specifically, for example, in the entry process, the child device 101C acquires the PAN_ID of the parent device 102A from the beacon BA, and stores the acquired PAN_ID in the flash memory in a nonvolatile manner.

  Also, the child device 101C transmits, for example, a connection request including its own long address and the PAN_ID of the parent device 102A, specifically, a Joining to the parent device 102A.

  When the parent device 102A receives the connection request from the child device 101C, the parent device 102A performs processing for confirming the content of the received connection request. When the parent device 102A confirms that the PAN_ID included in the connection request matches its own PAN_ID, the parent device 102A determines to manage the child device 101C.

  Then, authentication information is exchanged between the child device 101C and the parent device 102A using the long address included in the connection request, and the parent device 102A authenticates the child device 101C.

  Thereby, a direct communication connection is established between the child device 101C and the parent device 102A.

  Next, in a state where the PAN_ID is not stored in the flash memory, the child device 101C uses the PAN_ID of the parent device 102 that is the transmission destination of power information first as the PAN_ID of the parent device 102 that should be the transmission destination of power information. Is stored in the flash memory (step S214).

  Specifically, the child device 101C stores the PAN_ID of the parent device 102A, that is, “0001” in the flash memory.

  Next, the slave device 101C measures the power consumed in the measurement target (step S216).

  Next, the child device 101C transmits power information indicating the measurement result to the parent device 102A (step S218).

  Next, when receiving power information from the child device 101C, the parent device 102A accumulates the received power information and transmits an ACK indicating that the power information has been received to the child device 101C (step S220).

  Here, the operations in steps S216 to S220 are repeated, for example, periodically.

  The order of steps S204 to S208 is not limited to the above, and a part or all of the order may be changed.

  FIG. 7 is a diagram illustrating an example of a sequence when the child device performs the entry process again in the power information collection system according to the embodiment of the present invention.

  Referring to FIG. 7, a situation is assumed in which parent devices 102A, 102B, and 102C have already built a PA network and the transmission destination of power information of child device 101C is parent device 102A.

  First, the child device 101C leaves the PA network constructed by the parent device 102A (step S300).

  Specifically, the child device 101C is disconnected from the PA network constructed by the parent device 102A when its power is turned off by the user, for example, during maintenance and repair.

  Then, the slave device 101C is restored when the maintenance or repair is completed and its own power source is turned on by the user (step S302).

  Next, the child device 101C broadcasts a beacon request to search for the parent device 102 (step S304).

  Next, when receiving a beacon request from the child device 101C, the parent device 102C creates a beacon BC as a response to the received beacon request, and transmits the created beacon BC to the child device 101C (step S306).

  Next, when receiving a beacon request from the child device 101C, the parent device 102B creates a beacon BB as a response to the received beacon request, and transmits the created beacon BB to the child device 101C (step S308).

  Next, when receiving a beacon request from the child device 101C, the parent device 102A creates a beacon BA as a response to the received beacon request, and transmits the created beacon BA to the child device 101C (step S310).

  Next, when the child device 101C receives a beacon from the parent devices 102A, 102B, and 102C, the child device 101C performs a selection process based on each received beacon (step S312).

  More specifically, the child device 101C, for example, when performing the entry process for starting communication with the parent device 102 that is the transmission destination of the power information again, the parent of the target identification information that is the PAN_ID stored in the flash memory Entry processing is preferentially performed on the device 102.

  Specifically, since the child device 101C stores “0001” as the PAN_ID, that is, the target identification information in the flash memory, the parent device 102A having the PAN_ID of “0001” is preferentially set as the communication destination. Recognized as a parent device 102

  Then, the child device 101C confirms that the PAN_ID of “0001” is included in the beacon BA among the received beacons, and selects the parent device 102A as the parent device 102 that should be the communication destination.

  Next, the child device 101C performs an entry process for starting communication with the parent device 102A that is the transmission destination of the power information (step S314).

  The operations in steps S316 to S320 are the same as the operations in steps S216 to S220 shown in FIG.

  Note that the order of steps S306 to S310 is not limited to the above, and a part or all of the order may be changed.

  8 and 9 are diagrams showing an example of a sequence when the parent device stops operating in the power information collection system according to the embodiment of the present invention. FIG. 9 is a continuation of the sequence of FIG.

  Referring to FIGS. 8 and 9, assume a situation in which parent devices 102A, 102B, and 102C have already built a PA network, and the transmission destination of power information of child device 101C is parent device 102A. In addition, the parent device 102 includes, for example, a flash memory that can store information in a nonvolatile manner. In this example, the parent device 102 stores its own PAN_ID in the flash memory. Specifically, the parent device 102A stores “0001” in the flash memory as its own PAN_ID.

  First, the parent apparatus 102A stops its operation when its power is turned off by the user, for example, during maintenance and repair (step S402).

  Next, the slave device 101C measures the power consumed in the measurement target (step S404).

  Next, the child device 101C transmits power information indicating the measurement result to the parent device 102A (step S406).

  However, since the operation of the parent device 102A is stopped here, the child device 101C cannot receive the ACK from the parent device 102A.

  Next, the child device 101C recognizes that the parent device 102A that is the transmission destination of the power information is not operating normally, and broadcasts a beacon request to search for a new parent device 102 (step S408).

  However, here, the parent apparatus 102A does not receive the beacon request because the operation is stopped.

  Next, when receiving a beacon request from the child device 101C, the parent device 102C creates a beacon BC as a response to the received beacon request, and transmits the created beacon BC to the child device 101C (step S410).

  Next, when receiving a beacon request from the child device 101C, the parent device 102B creates a beacon BB as a response to the received beacon request, and transmits the created beacon BB to the child device 101C (step S412).

  Next, when receiving a beacon from the parent devices 102B and 102C, the child device 101C performs a selection process based on each received beacon (step S414).

  More specifically, when the child device 101C cannot recognize the parent device 102A of the target identification information, for example, when performing the entry process for starting communication with the parent device 102A that is the transmission destination of the power information again, Entry processing is performed on the other parent device 102 selected based on the communication quality.

  Specifically, although the slave device 101C stores “0001” as the PAN_ID in the flash memory, the beacon BB is transmitted because the received beacon BB and BC do not include the PAN_ID of “0001”. From the parent device 102B and the parent device 102C that has transmitted the beacon BC, the parent device 102 that should be the communication destination is selected.

  Here, the child device 101C selects, for example, the parent device 102 having the best communication quality with itself, in this example, the parent device 102B, as the parent device 102 that should be the communication destination.

  Next, the child device 101C performs an entry process for starting communication with the parent device 102B as a new transmission destination of the power information (step S416).

  Next, the slave device 101C measures the power consumed in the measurement target (step S418).

  Next, the child device 101C transmits power information indicating the measurement result to the parent device 102B (step S420).

  Next, when receiving power information from the slave device 101C, the master device 102B accumulates the received power information and transmits an ACK indicating that the power information has been received to the slave device 101C (step S422).

  Here, the operations in steps S418 to S422 are repeated periodically, for example.

  Next, for example, in a state where the parent device 102 having a PAN_ID different from the target identification information is set as the transmission destination of the power information, the child device 101C searches for the target parent device that is the parent device 102 of the target identification information. Processing is performed (step S424).

  Specifically, the child device 101C broadcasts a beacon request to search for the target parent device, that is, the parent device 102A.

  However, here, the parent apparatus 102A does not receive the beacon request because the operation is stopped.

  Next, when receiving the beacon request from the child device 101C, the parent device 102C creates a beacon BC as a response to the received beacon request, and transmits the created beacon BC to the child device 101C (step S426).

  Next, when receiving a beacon request from the child device 101C, the parent device 102B creates a beacon BB as a response to the received beacon request, and transmits the created beacon BB to the child device 101C (step S428).

  Next, when receiving the beacon from the parent devices 102B and 102C, the child device 101C performs a determination process for determining whether or not the search for the parent device 102A is successful based on each received beacon (step S430).

  Here, since the received beacons BB and BC do not include the target identification information, that is, the PAN_ID of “0001”, the child device 101C determines that the search for the parent device 102A has failed.

  Here, the operations in steps S424 to S430 are repeated, for example, periodically.

  Next, the parent device 102A is restored when the maintenance or repair is completed and its own power source is turned on by the user (step S432).

  Next, the parent apparatus 102A sets PAN_ID held in the flash memory, that is, “0001” as its own PAN_ID (step S434).

  Next, the child device 101C broadcasts a beacon request to search for the target parent device, that is, the parent device 102A (step S436).

  Next, when receiving the beacon request from the child device 101C, the parent device 102C creates a beacon BC as a response to the received beacon request, and transmits the created beacon BC to the child device 101C (step S438).

  Next, when receiving a beacon request from the child device 101C, the parent device 102B creates a beacon BB as a response to the received beacon request, and transmits the created beacon BB to the child device 101C (step S440).

  Next, when receiving a beacon request from the child device 101C, the parent device 102A creates a beacon BA as a response to the received beacon request, and transmits the created beacon BA to the child device 101C (step S442).

  Next, when receiving the beacon from the parent devices 102A, 102B, and 102C, the child device 101C performs a determination process based on each received beacon (step S444).

  Here, since the received beacon BA includes the target identification information, that is, the PAN_ID of “0001”, the child device 101C determines that the search for the parent device 102A has succeeded.

  Next, when the child device 101C finds the target parent device, that is, the parent device 102A, for example, the child device 101C performs a switching process that is a process of switching the transmission destination of the power information to the target parent device (step S446).

  Specifically, the child device 101C performs a leaving process for leaving from the management of the parent device 102B, and then performs a joining process for starting communication with the parent device 102A that is the transmission destination of the power information.

  Note that the order of steps S410 and S412 is not limited to the above, and the order may be changed. The order of steps S426 and S428 is not limited to the above, and the order may be changed. The order of steps S438 to S442 is not limited to the above, and a part or all of the order may be changed.

[Modification of switching process]
The child device 101 </ b> C is not limited to the configuration in which the device itself performs the switching process, but may be configured to perform the switching process in accordance with an instruction from another device, for example, the server 103.

  10 and 11 are diagrams illustrating an example of a sequence when the parent device stops operating in the power information collection system according to the embodiment of the present invention. FIG. 11 is a continuation of the sequence of FIG.

  Referring to FIG. 10 and FIG. 11, a situation is assumed in which parent devices 102A, 102B, and 102C have already built a PA network, and the transmission destination of power information of child device 101C is parent device 102A. The parent device 102A stores “0001” in the flash memory as its own PAN_ID.

  The operations in steps S502 to S522 are the same as the operations in steps S402 to S422 shown in FIG.

  Next, the parent device 102B transmits entry information to the server 103 via the Internet 10 (step S524). This entry information includes the PAN_ID of the parent device 102B, the long address of each child device 101 that has entered the parent device 102B, the number of child devices 101 that have entered the parent device 102B, and the like.

  Next, the parent device 102C transmits entry information to the server 103 via the Internet 10 (step S526). This entry information includes the PAN_ID of the parent device 102C, the long address of each child device 101 that has entered the parent device 102C, the number of child devices 101 that have entered the parent device 102C, and the like.

  Next, when the entry information is received from the parent devices 102B and 102C, the server 103 performs a status confirmation process for confirming the management status of the child device 101 in each parent device 102 based on the received entry information (step S528). ).

  More specifically, for example, the server 103 checks whether or not the number of child devices 101 managed by the parent device 102 is appropriate based on each entry information.

  Here, for example, the server 103 determines that there are too many child devices 101 managed by the parent devices 102B and 102C, but maintains the current state because there is no receiving destination for the child devices 101.

  Here, the operations in steps S524 to S528 are repeated, for example, periodically.

  Next, the parent device 102A is restored when the maintenance or repair is completed and its power source is turned on by the user (step 532).

  Next, the parent apparatus 102A sets PAN_ID held in the flash memory, that is, “0001” as its own PAN_ID (step S534).

  Next, the parent device 102A transmits entry information to the server 103 via the Internet 10 (step S536).

  Next, the parent device 102B transmits entry information to the server 103 via the Internet 10 (step S538).

  Next, the parent device 102C transmits entry information to the server 103 via the Internet 10 (step S540).

  Next, when the entry information is received from the parent devices 102A, 102B, and 102C, the server 103 performs a status confirmation process based on the received entry information (step S542).

  Here, for example, since the server 103 can confirm the parent device 102A as the receiving destination of the child device 101 based on each entry information, the parent device 102A should manage the child device 101C managed by the parent device 102B. to decide.

  Next, the server 103 transmits designation information for designating the transmission destination of the power information of the child device 101C to the parent device 102A, for example, to the parent device 102B via the Internet 10 (step S544).

  This designation information includes, for example, the long address of the child device 101C as the transmission destination of the designation information, and the PAN_ID of the parent device 102A to which the child device 101C should enter, that is, “0001”.

  When the parent device 102B receives the designation information from the server 103, the parent device 102B transmits the received designation information to the child device 101C via the power line 161 (step S546).

  Next, the child device 101C, for example, again performs an entry process for starting communication with the parent device 102 that is the transmission destination of power information, and then has a PAN_ID that is different from that of the parent device 102B that is the transmission destination of power information. When the designation is received from a predetermined device, here the server 103, a switching process is performed which is a process of switching the transmission destination of the power information to the parent device 102 of the designated PAN_ID (step S548).

  Specifically, when the child device 101C receives the designation information from the parent device 102B, the child device 101C performs a detachment process for leaving the management of the parent device 102B according to the received designation information, and then the parent device that is the transmission destination of the power information. An entry process for starting communication with the apparatus 102A is performed.

  The order of steps S510 and S512 is not limited to the above, and the order may be changed. Further, the order of steps S524 and S526 is not limited to the above, and the order may be changed. The order of steps S536 to S540 is not limited to the above, and a part or all of the order may be changed.

  In the power information collection system according to the embodiment of the present invention, the PAN_ID is used as identification information that can identify the parent device. However, the present invention is not limited to this. A configuration in which a short address is used as identification information that can identify the parent device may be used. Specifically, the short addresses of the parent devices 102A, 102B, and 102C can be set to values other than zero, for example, and are set to values that do not overlap each other in a predetermined parent device address space. The The short address of the child device 101 belonging to the same PA network is set to a value that does not overlap with each other from a predetermined address space for the child device that does not overlap with the parent device address space. In this case, the PAN_IDs set by the parent devices 102A, 102B, and 102C may be the same, or some or all of them may be different.

  Specifically, the parent device 102A receives a notification of the short address in use from the parent devices 102B and 102C, and sets a short address that does not overlap with one or more of the notified short addresses as its own short address. . Then, in a state where the short address of the parent device 102 is not stored in the flash memory, the child device 101C should use the short address of the parent device 102A that is the first transmission destination of the power information as the transmission destination of the power information. The short address of the parent device 102 is stored in the flash memory.

  In the power information collection system according to the embodiment of the present invention, the child device 101 preferentially enters the parent device 102 of the target identification information stored in the flash memory when the entry process is performed again. Although it is the structure which performs a process, it is not limited to this. The child device 101 may be configured to always perform the entry process on the parent device 102 of the target identification information when the entry process is performed again. In this case, the child device 101 does not perform entry processing on the parent device 102 other than the parent device 102 of the target identification information.

  In the power information collection system according to the embodiment of the present invention, when the child device 101 cannot recognize the parent device 102 of the target identification information when performing the entry process again, the child device 101 selects based on the communication quality with itself. However, the present invention is not limited to this. For example, the rank of the parent device 102 to which the child device 101 should enter is determined in advance, and when the child device 101 performs the entry process again, the child device 101 selects another parent device 102 selected based on the rank. The structure which performs an entry process may be sufficient.

  Further, in the power information collection system according to the embodiment of the present invention, the child device 101 sets the target identification information in a state where the parent device 102 having identification information different from the target identification information is set as the transmission destination of the power information. However, the present invention is not limited to this. The child device 101 may be configured not to search for the target parent device. In this case, for example, the child device 101 does not transmit a beacon request and does not receive a beacon, and uses the PAN_ID of the target parent device stored in the flash memory and its own long address, Regularly try to establish a communication connection.

  In the power information collection system according to the embodiment of the present invention, the parent device 102 designated by the designation information transmitted by the server 103 is the parent device 102A of the target identification information. However, the present invention is not limited to this. Absent. The parent device 102 designated by the designation information may be a parent device 102 other than the parent device 102A of the target identification information. More specifically, for example, when the number of child devices 101 managed by the parent device 102A that is the target parent device is excessive, the server 103 is a parent other than the parent device 102A as a transmission destination of power information of the child device 101C. Specify the device 102.

  Further, in the power information collection system according to the embodiment of the present invention, when the child device 101C receives the designation information from the server 103 via the parent device 102B after performing the entry process again, the child device 101C sets the transmission destination of the power information. Although the configuration is such that the switching process for switching to the parent device 102A of the PAN_ID indicated by the designation information is performed, the present invention is not limited to this. The slave device 101C may be configured not to perform the switching process even if the designation information is received from the server 103 based on some determination.

  Incidentally, in a communication system including a parent device and a child device such as the communication network described in Patent Document 1, the number of child devices managed by the parent device may become excessive. In such a case, the communication frequency between the parent device and the child device increases, and the packet loss rate may increase. There is a need for technology that can prevent the number of slave units managed by the master unit from becoming excessive.

  On the other hand, the power information collection system according to the embodiment of the present invention includes a child device 101 that acquires power information and a plurality of parent devices 102. The child device 101 communicates with the parent device 102 that belongs to the same PA network and is the transmission destination of the power information via the power line 161 using identification information that can identify the parent device 102. The parent device 102 receives notification of identification information in use from one or more other parent devices 102, and sets identification information that does not overlap with the received one or more identification information as its own identification information. Then, the child device 101 has a storage area in which information can be stored in a nonvolatile manner, and the identification information of the parent device 102 that is the first transmission destination of the power information in a state where the identification information is not stored in the storage area Is stored in the storage area as identification information of the parent device 102 that is to be the transmission destination of the power information.

  As described above, in a state where the identification information is not stored in the storage area, the identification information of the parent device 102 that is the transmission destination of the power information first is used as the identification information of the parent device 102 that is to be the transmission destination of the power information. With the configuration of saving in the storage area, for example, the child device 101 is based on the identification information in the storage area even when the power is turned on again after the power supply of the child device 101 is turned off and removed from the management of the parent device 102. Since the parent device 102 that should be the transmission destination of the power information can be recognized, it is possible to prevent the transmission destination of the power information from being erroneously set to another parent device 102. Further, for example, when the power is turned on again, the parent device 102 has stopped operating, so even if the child device 101 accidentally enters the management of another parent device 102, the child device 101 stores the memory. Since it is possible to recognize that the transmission destination of the power information is incorrect based on the identification information in the area, it is possible to leave the management of the other parent device 102 or to follow another parent device according to an instruction from the other device. 102 can be withdrawn from the management of 102. As a result, it is possible to prevent the number of slave units managed by the master unit from becoming excessive. For example, it is possible to prevent an increase in the packet loss rate.

  In the power information collection system according to the embodiment of the present invention, the child device 101 stores the identification information stored when the entry processing for starting communication with the parent device 102 that is the transmission destination of the power information is performed again. Entry processing is preferentially performed on the parent device 102 of the target identification information.

  With such a configuration, when the entry process is performed again, it is possible to reduce the possibility that the transmission destination of the power information is mistaken for the parent device 102 different from the parent device 102 of the target identification device.

  In the power information collection system according to the embodiment of the present invention, when the child device 101 performs the entry process for starting communication with the parent device 102 that is the transmission destination of the power information again, When the parent device 102 cannot be recognized, the entry process is performed on the other parent device 102 selected based on the communication quality with itself.

  With such a configuration, even in a situation where power information cannot be transmitted to the parent device 102 of the target identification information, power information can be transmitted to another parent device 102 that can communicate with higher quality. A situation where information cannot be transmitted can be avoided.

  In the power information collection system according to the embodiment of the present invention, the child device 101 sets the parent device 102 having identification information different from the target identification information that is the stored identification information as the transmission destination of the power information. In the state, a process of searching for the target parent device that is the parent device 102 of the target identification information is performed. When the child device 101 finds the target parent device, the child device 101 performs a process of switching the transmission destination of the power information to the target parent device.

  With such a configuration, even if the child device 101 erroneously sets the transmission destination of the power information to the parent device 102 having identification information different from the target identification information, as soon as the target parent device is discovered, A process of switching the transmission destination to the target parent device can be performed. As a result, it is possible to prevent the child device 101 from continuing to transmit power information to an incorrect transmission destination.

  In the power information collection system according to the embodiment of the present invention, the child device 101 performs the entry process for starting communication with the parent device 102 that is the transmission destination of the power information again, and then transmits the power information. When designation of identification information different from the parent device 102 that is the destination is received from a predetermined device such as the server 103, processing for switching the transmission destination of power information to the parent device 102 of the designated identification information is performed.

  With such a configuration, when the child device 101 performs the entry process again, for example, when another parent device 102 different from the parent device 102 of the identification information in the storage area is used as the transmission destination of the power information In accordance with the instruction from the server 103, the transmission destination of the power information can be switched to the parent device 102 of the identification information in the storage area. Thereby, it is possible to prevent the child device 101 from continuing the transmission of the power information to the other parent device 102.

  The above embodiment should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The above description includes the following features.

[Appendix 1]
A slave device for acquiring power information;
With multiple parent devices,
The child device communicates via the power line with the parent device that belongs to the same network and is the transmission destination of the power information, using identification information that can identify the parent device,
The parent device receives notification of the identification information in use from one or more other parent devices, and the identification information that does not overlap with the one or more identification information received is received as the identification information of the parent device. Set as
The child device has a storage area capable of storing information in a nonvolatile manner, and in a state where the identification information is not stored in the storage area, the child device of the parent device that is the transmission destination of the power information first The identification information is stored in the storage area as the identification information of the parent device to be the transmission destination of the power information,
The child device is a smart meter,
The parent device is a concentrator;
The identification information is a PAN_ID (Personal Area Network Identification) or a short address,
The parent device broadcasts a beacon request to search for the other one or more parent devices;
When the other one or more parent devices receive a beacon request from the parent device, the other one or more parent devices transmit a beacon including the identification information in use to the parent device,
When the parent device receives the beacon from the other one or more parent devices, the parent device assigns the identification information that does not overlap with the one or more identification information based on the received one or more beacons. Set as identification information for
The child device has a flash memory as the storage area.

10 Internet 71 MAC Frame 101 Child Device 102 Parent Device 103 Server 104 Transformer 151 Apartment House 161 Power Line 171 Power System 301 Power Information Collecting System

Claims (6)

A slave device for acquiring power information;
With multiple parent devices,
The child device communicates via the power line with the parent device that belongs to the same network and is the transmission destination of the power information, using identification information that can identify the parent device,
The parent device receives notification of the identification information in use from one or more other parent devices, and the identification information that does not overlap with the one or more identification information received is received as the identification information of the parent device. Set as
The child device has a storage area capable of storing information in a nonvolatile manner, and in a state where the identification information is not stored in the storage area, the child device of the parent device that is the transmission destination of the power information first The power information collection system which preserve | saves identification information in the said storage area as said identification information of the said parent apparatus which should be the transmission destination of the said power information.   When the child device performs the entry process for starting communication with the parent device as the transmission destination of the power information again, the child device has priority over the parent device of the target identification information that is the stored identification information. The power information collection system according to claim 1, wherein the entry process is performed.   In the case where the child device cannot recognize the parent device of the target identification information when performing the entry process for starting communication with the parent device that is the transmission destination of the power information, the communication quality with itself is improved. The power information collection system according to claim 2, wherein the entry process is performed on another parent device selected on the basis of the entry processing.   The child device is the parent device of the target identification information in a state where the parent device of the identification information different from the target identification information that is the stored identification information is set as a transmission destination of the power information 4. The process according to claim 1, wherein a process of searching for a target parent apparatus is performed, and when the target parent apparatus is found, a process of switching the transmission destination of the power information to the target parent apparatus is performed. Power information collection system.   The child device performs the entry process for starting communication with the parent device that is the transmission destination of the power information, and then specifies the identification information that is different from the parent device that is the transmission destination of the power information. The power information according to any one of claims 1 to 4, wherein when receiving the power information from a predetermined device, a process of switching the transmission destination of the power information to the parent device of the specified identification information is performed. Collection system. A communication control method in a power information collection system comprising a child device for acquiring power information and a plurality of parent devices,
The child device has a storage area in which information can be stored in a nonvolatile manner, the parent device belonging to the same network, and the parent device that is the transmission destination of the power information, and an identification that can identify the parent device Communicate via the power line using information,
The parent device receives the notification of the identification information in use from one or more other parent devices, and the identification information that does not overlap with the one or more identification information received is the identification information of itself. Step to set as
In the state where the identification information is not stored in the storage area, the child device should use the identification information of the parent device that is the transmission destination of the power information first as the transmission destination of the power information. Storing in the storage area as the identification information of the parent device.

Images