WO2018225226A1

WO2018225226A1 - Information collection device, automatic meter-reading system, and path updating method

Info

Publication number: WO2018225226A1
Application number: PCT/JP2017/021379
Authority: WO
Inventors: 佑太中西; 小林　敬侍
Original assignee: 三菱電機株式会社
Priority date: 2017-06-08
Filing date: 2017-06-08
Publication date: 2018-12-13
Also published as: JPWO2018225226A1; JP6664549B2

Abstract

An information collection device (1) is provided with: an information collection unit (31) that acquires measurement information that is a result of measurement of electricity information from a smart meter placed at each of a plurality of consumers for measuring electricity information related to the electric power of the consumer; a load status monitoring unit (33) that monitors, on the basis of the measurement information, the status of the load at the consumer; and a path updating unit (34) that updates, on the basis of the status of the load at the consumer, the path in a multihop communication.

Description

Information collection device, automatic meter reading system, and route update method

The present invention relates to an information collecting apparatus, an automatic meter reading system, and a route updating method for collecting information on electric power at each customer by using power line communication (hereinafter referred to as PLC).

In recent years, an automatic meter reading system in which a smart meter is installed at each consumer and an information collecting device called a concentrator collects information such as the amount of power used by each consumer through a communication function has become widespread. There are several communication methods used in the automatic meter reading system, and one of them is PLC.

PLC has different attenuation characteristics and noise characteristics for each slave unit between a single master unit and a plurality of slave units for communication. Therefore, a technique is used in which a path in multi-hop communication between the parent device and each child device is constructed based on the communication quality between the parent device and each child device. For example, in the invention described in Patent Document 1, the communication quality between the slave units is detected, and the route with the detected good communication quality is selected to construct the route.

Japanese Patent Laid-Open No. 2015-220657

Various electrical devices such as home appliances and network terminals are connected to the outlets in the customer's homes, and the load state of the consumer changes from moment to moment depending on the connection status and operation status of these electrical devices. And depending on the load state in a consumer, the noise which rides on the power line used as a communication line may increase, and communication quality may fall.

In the case of apartment houses such as condominiums, a common power line is provided, and power is branched and supplied from the common power line to the power line of each consumer. Therefore, when an automatic meter-reading system is formed by smart meters and information collection devices installed in apartment houses, the effects of noise generated by one consumer are affected by smart meters and information collection devices installed by other consumers. There is a possibility that inconveniences such as the inability to collect meter reading data, which is information such as the amount of power used, over a wide range may occur.

In the technique described in Patent Document 1, the communication quality between the slave units is detected, and the route with the detected good communication quality is selected and updated. Until it is reconstructed, it is difficult to suppress a decrease in communication quality in the PLC.

The present invention has been made in view of the above, and an object thereof is to obtain an information collection device, an automatic meter reading system, and a route update method that can suppress a decrease in communication quality in a PLC.

In order to solve the above-described problems and achieve the object, the present invention provides a multi-hop communication using a smart meter and a power line that are installed in each of a plurality of consumers and measure electrical information related to the power of the consumers. In the information collecting device to perform, an information collecting unit that acquires measurement information that is a measurement result of the electrical information from the smart meter, and a load state monitoring unit that monitors a load state in the consumer based on the measurement information; And a route updating unit that updates a route in the multi-hop communication based on the state of the load.

According to the present invention, there is an effect that it is possible to suppress a decrease in communication quality in the PLC.

The figure which shows the structural example of the automatic meter-reading system concerning Embodiment 1. FIG. The figure which shows the relationship between the smart meter installed in the consumer concerning Embodiment 1, a power line, and the load of a consumer. The figure which shows an example of the path | route state before and behind reconstruction by the information collection device concerning Embodiment 1. The figure which shows the time change of the electric power consumption in the consumer concerning Embodiment 1. FIG. The figure which shows the structural example of the smart meter concerning Embodiment 1. FIG. 1 is a diagram illustrating a configuration example of an information collection device according to a first embodiment. FIG. 3 is a diagram illustrating an example of a physical arrangement table according to the first embodiment. The figure which shows an example of the measurement information table concerning Embodiment 1. FIG. The figure which shows an example of the proximity search request message concerning Embodiment 1. The figure which shows an example of the proximity search response message concerning Embodiment 1. The figure which shows an example of the entry request message transmitted from the smart meter which performs the new entry concerning Embodiment 1 The figure which shows an example of the entry request message transferred with the smart meter concerning Embodiment 1. The figure which shows a part of route candidate table concerning Embodiment 1 as an example. The figure which shows an example of the route information of each smart meter concerning Embodiment 1. The figure which shows an example of the routing information which each smart meter concerning Embodiment 1 hold | maintains The figure which shows an example of the information request message concerning Embodiment 1. FIG. 3 is a sequence diagram showing an operation example of the automatic meter reading system according to the first embodiment. 10 is a flowchart illustrating an example of a load increase node detection process according to the first embodiment. 3 is a flowchart illustrating an example of a collection cycle changing process according to the first embodiment. FIG. 3 is a flowchart illustrating an example of a route reconstruction process according to the first embodiment; 10 is a flowchart illustrating an example of a route reconstruction process with priority on the S / N ratio according to the first embodiment; 1 is a flowchart illustrating an example of a bypass route table creation process according to the first embodiment; The figure which shows an example of the bypass route table concerning Embodiment 1. FIG. 1 is a flowchart illustrating an example of an S / N ratio change process according to the first embodiment. The figure which shows an example of the route candidate table when the S / N ratio for routes concerning Embodiment 1 is changed. FIG. 3 is a flowchart illustrating an example of a route reconstruction process according to the first embodiment; 1 is a diagram illustrating a hardware configuration example of an information collection apparatus according to a first embodiment; The figure which shows the structural example of the information collection device concerning Embodiment 2. 10 is a flowchart illustrating an example of a route reconstruction process with priority on the S / N ratio according to the second embodiment; The flowchart which shows an example of the bypass route table preparation process of the adjacent node concerning Embodiment 2. 10 is a flowchart illustrating an example of an S / N ratio change process according to the second embodiment.

Hereinafter, an information collection device, an automatic meter reading system, and a route update method according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a diagram illustrating a configuration example of an automatic meter reading system according to the first embodiment. As shown in FIG. 1, an automatic meter reading system 100 according to a first embodiment includes an information collection device 1 that collects electrical information related to electric power at a consumer, and smart meters 2-11 and 12-12 installed at the consumer. , 2-13, 2-14, ..., 2-1n, 2-21, 22-22, 2-23, 2-24, ..., 2-2m. “N” and “m” are integers of 5 or more, and may be described below as n = 5.

Each of the smart meters 2-11, 12-12, 2-13, 2-14,..., 2-1n is connected to power lines 4-11, 4-12, 4-13, 4-14,. -1n to the common power line 3-1. Similarly, each smart meter 2-21, 22-22, 2-23, 2-24,..., 2-2 m is connected to power lines 4-21, 4-22, 4-23, 4-24,. -It is connected to the common power line 3-2 via 4-2m.

In the following explanation, smart meters 2-11, 12-12, 2-13, 2-14,..., 2-1n, 2-21, 22-22, 2-23, 2-24, ..., 2-2m may be described as smart meter 2 without distinction. Further, each of the power lines 3-1 and 3-2 is referred to as a power line 3 without being distinguished, and the power lines 4-11, 4-12, 4-13, 4-14,. 21, 4-22, 4-23, 4-24,..., 4-2 m may be described as the power line 4 without being distinguished from each other. The automatic meter reading system 100 is installed in a housing complex such as an apartment. The smart meter 2 is installed in each room of the apartment house. The number of smart meters 2, the number of power lines 3, and the number of power lines 4 are not limited to the example shown in FIG. 1, and the installation target of the automatic meter reading system 100 is not limited to a housing complex.

FIG. 2 is a diagram showing the relationship between the smart meter 2 installed in the consumer, the power line 4, and the consumer's electrical equipment. As shown in FIG. 2, the power line 4 is connected to the consumer electrical devices 8-1, 8-2,..., 8 -k via the smart meter 2 installed in the consumer. “K” is an integer of 2 or more. The state of the load on the consumer varies depending on the number, type, and operating state of the electrical devices 8-1, 8-2,. Hereinafter, the electric devices 8-1, 8-2,..., 8-k are collectively referred to as an electric device 8.

In the automatic meter reading system 100 shown in FIG. 1, the information collection device 1 collects data from each smart meter 2 by PLC performed via the power line 3. The information collection device 1 has a function of operating as a master device for the PLC. Each smart meter 2 has a function of measuring electrical information related to power supplied from the power line 4 to the consumer's electrical equipment 8 and a function of operating as a slave unit of the PLC.

The information collection device 1 and each smart meter 2 form a PLC network, and transmit and receive data by multi-hop communication. That is, each smart meter 2 has a function of relaying data. When data addressed to the information collection device 1 is received from another smart meter 2, the received data is transferred to the information collection device 1. Further, when the information collection device 1 receives data addressed to the other smart meter 2 of the transmission source, each smart meter 2 transfers the received data to the other smart meter 2 of the destination.

Hereinafter, each of the information collection device 1 and the smart meter 2 forming the PLC network may be referred to as a “node”, and identification information of each of the information collection device 1 and the smart meter 2 may be referred to as a node ID. Further, communication between nodes on the route is described as hops, and the number of communication between nodes is described as the number of hops. Note that the node that is the destination of data from any node on the route is described as “next hop node”, and the node that is the source of data transmission to any node on the route is referred to as “previous hop node”. May be described.

Also, in the following, it is assumed that the node ID is the one in which the sign of each of the information collection device 1 and the smart meter 2 is prefixed with “N”. For example, the node ID of the information collection device 1 is “N1”, the node ID of the smart meter 2-11 is “N2-11”, and the node ID of the smart meter 2-2m is “N2-2m”. Note that the node ID is not limited to the above example.

Each of the information collection device 1 and the smart meter 2 has a function of calculating an S / N ratio at the time of signal reception on the PLC network. The S / N ratio is information indicating communication quality, and is a signal-to-noise ratio. The information collection device 1 acquires the S / N ratio from each smart meter 2 and constructs a path between the information collection device 1 and each smart meter 2 based on the acquired S / N ratio. Thereby, the path | route which considered the communication quality between the information collection device 1 and each smart meter 2 can be constructed | assembled.

Furthermore, the information collection device 1 monitors the load state of each customer based on the measurement information acquired from each smart meter 2, and collects information before the communication quality in the PLC deteriorates due to the increase in load. The path between the device 1 and each smart meter 2 can be reconstructed. Thereby, the fall of the communication quality in PLC can be suppressed.

FIG. 3 is a diagram illustrating an example of a path state before and after reconstruction by the information collection apparatus 1. In the first route shown in FIG. 3, the route from the smart meter 2-1n to the information collecting device 1 includes the smart meters 2-14 and 2-12, and the information collected from the smart meter 2-1n is collected. Data addressed to the device 1 is sequentially transferred by the smart meters 2-14 and 2-12 and received by the information collecting device 1.

When noise is increased due to an increase in load at a customer where the smart meter 2-13 is installed, not only communication between the smart meter 2-13 and the information collecting device 1 but also smart meters other than the smart meter 2-13 2 and the information collecting apparatus 1 may also be affected. This is because a plurality of smart meters 2-11, 12-12, 2-13, 2-14,..., 2-1n are connected to the common power line 3-1, and the smart meter 2-13 is connected. This is because noise is transmitted to the common power line 3-1 through the power line 4-13.

Therefore, the information collection device 1 updates and reconstructs the route when the load state at the customer where the smart meter 2 is installed satisfies the route update condition set in advance. The route update condition includes a condition of at least one state of electric power and current supplied to the electric device 8.

FIG. 4 is a diagram showing a temporal change in the amount of power used, which is the amount of power supplied to the customer's electrical equipment 8 via the power line 4. In FIG. 4, the horizontal axis represents time, and the vertical axis represents the amount of power used. The information collection device 1 determines that the route update condition is satisfied when the power amount data indicating the power usage amount of the consumer is equal to or greater than the threshold value Pth1. In the example illustrated in FIG. 4, a threshold value Pth <b> 1 is set that is smaller than the amount of power used that generates noise having a magnitude that affects communication quality in the PLC. The information collection device 1 reconstructs the path of the PLC network when the power amount data is equal to or greater than the threshold value Pth1.

Note that the route update condition described above is not limited to the amount of power data being equal to or greater than the threshold value Pth1, and the route update condition includes the rate of increase in the amount of power data and the value of the current supplied to the consumer's electrical equipment 8. It may be the condition of the magnitude of the current value data to be shown or the rate of increase of the current value data. The path update condition may be a condition in which two or more of the magnitude of the power amount data, the increase rate of the power amount data, the magnitude of the current value data, and the increase rate of the current value data are combined. In other words, the route update condition is set so that it is possible to detect that the load state may be a state in the previous stage of the state in which noise of a magnitude that reduces communication quality in the PLC is generated. Just do it.

The second route shown in FIG. 3 shows a route reconstructed when the load state at the customer where the smart meter 2-13 is installed satisfies the route update condition. A smart meter 2-13 installed at a customer who satisfies the above-described route update condition is added to the route from the smart meter 2-1n to the information collection device 1.

In the second route shown in FIG. 3, the data addressed to the information collecting device 1 transmitted from the smart meter 2-1n is transferred by the smart meter 2-13 in addition to the smart meters 2-14 and 2-12, Received by the collection device 1. In this way, the communication path between the information collection device 1 and the smart meter 2-1n is reconstructed so that the number of hops increases near the customer who satisfies the path update condition.

Therefore, it is possible to reduce the length of the portion where the signal is transmitted in one hop in the power line 3-1 near the consumer where the noise is expected to be generated to reduce the communication quality in the PLC. Can be reduced. For this reason, even when noise increases, it is possible to suppress a decrease in communication quality between the information collection device 1 and the smart meter 2-1n.

In the above example, the communication path between the information collection device 1 and the smart meter 2-1n has been described. However, the communication between the smart meter 2 other than the smart meter 2-1n and the information collection device 1 is described. The route is similarly reconstructed based on the route update condition.

FIG. 5 is a diagram illustrating a configuration example of the smart meter 2 according to the first embodiment. The smart meter 2 includes a measurement terminal 5 that measures electrical information related to the power supplied to the electrical device 8, and a PLC slave module 6 that transmits the measurement value measured by the measurement terminal 5 to the information collection device 1 as measurement information. .

The measurement terminal 5 measures information related to the power supplied to the electrical device 8 through the power line 4 connected to the smart meter 2, specifically, voltage, current, demand, power amount, harmonics, and the like. Unit 51, a storage unit 52 that stores measurement information that is information including measurement values measured by the measurement unit 51 and measurement time information that is measurement time, and a request from the PLC slave module 6 And a control unit 53 that reads out the measurement information stored in the storage unit 52 and outputs the measurement information to the PLC slave module 6.

The PLC slave module 6 includes a control unit 61 that acquires measurement information from the measurement terminal 5, a storage unit 62 that stores measurement information acquired by the control unit 61 from the measurement terminal 5, and another smart meter 2 or information collection. And a communication unit 63 that transmits and receives signals to and from the device 1.

The communication unit 63 is connected to the power line 3 via the power line 4, receives data addressed to the information collection device 1 including measurement information acquired from the measurement terminal 5 from the control unit 61, and receives the received data addressed to the information collection device 1 Is transmitted via the power line 4 and the power line 3. Further, the communication unit 63 receives a message and data from the information collection device 1 via the power line 3 and the power line 4. Furthermore, when the communication unit 63 receives the data addressed to the parent device, which is the data addressed to the information collection device 1 transmitted from the other smart meter 2, the communication unit 63 transfers the received data addressed to the parent device.

It should be noted that the control unit 61 determines whether or not the data addressed to the parent device transmitted from the other smart meter 2 has been received. The PLC slave unit module 6 calculates the S / N ratio when receiving data addressed to the master unit from another smart meter 2, and stores the calculated S / N ratio. The communication unit 63 calculates the S / N ratio. The S / N ratio calculated by the communication unit 63 is stored in the storage unit 62 together with the time when the S / N ratio is calculated.

When the communication unit 63 calculates the S / N ratio, the control unit 61 calculates the calculated S / N ratio and the smart meter 2 that is the transmission source of the data addressed to the parent device received when the S / N ratio is calculated. And the acquired S / N ratio and the node ID of the transmission source smart meter 2 are stored in the storage unit 62 in association with each other. In addition to the S / N ratio calculated by the communication unit 63 and the corresponding node ID of the smart meter 2, the storage unit 62 also stores route information when relaying data addressed to the parent device.

FIG. 6 is a diagram illustrating a configuration example of the information collection device 1 according to the first embodiment. The main functions of the information collection device 1 are regular collection of information from the smart meter 2, management of the communication status of the PLC network, and route management of the PLC network. The route management of the PLC network includes a process of constructing and reconstructing a communication route between the information collection device 1 and each smart meter 2.

The information collection device 1 manages a communication unit 10 that transmits and receives signals to and from each of the smart meters 2, a storage unit 20 that stores various types of information including measurement information, a PLC network, and a communication unit 10. And a control unit 30 that collects information from each smart meter 2.

The communication unit 10 is connected to each of the smart meters 2 via the power line 3 and transmits / receives a signal to / from each of the smart meters 2 having a function of a slave unit of the PLC as a master unit of the PLC. The communication unit 10 calculates the S / N ratio when receiving a signal including data such as measurement information from the smart meter 2.

The storage unit 20 includes a physical arrangement table 21 that includes information on physical routes of distribution lines from the information collection device 1 to each smart meter 2, and a measurement information table 22 that includes measurement information collected from each smart meter 2. And a route candidate table 23 including information on route candidates of each smart meter 2, and a route information storage area 24 for storing route information indicating the route of each smart meter 2.

FIG. 7 is a diagram illustrating an example of the physical arrangement table 21. The physical arrangement table 21 illustrated in FIG. 7 includes information in which node IDs of two smart meters 2 physically adjacent to each other via the power line 3 are associated. The phrase “physically adjacent” means that the connection position to the power line 3 is adjacent.

The physical arrangement table 21 shown in FIG. 7 includes a “node ID” of each smart meter 2, a “neighbor node ID” that is a node ID of an adjacent node that is another smart meter 2 adjacent to each smart meter 2, and an adjacent node. It includes information associated with “position”, which is information indicating a physical positional relationship with the node via the power line 3. In the case of the power line 3-1, the connection position of the smart meter 2-1n is the lowest position, and the closer to the information collection device 1, the higher the position, and the information collection device 1 is the highest position.

In the connection state shown in FIG. 1, the information collecting device 1 and the smart meter 2-11 are physically adjacent via the power line 3. The smart meter 2-11 is positioned at the lower position when viewed from the information collecting apparatus 1, and the information collecting apparatus 1 is positioned at the upper position when viewed from the smart meter 2-11. Therefore, as shown in FIG. 7, a combination of “N1”, “N2-11”, and “lower” and a combination of “N2-11”, “N1”, and “upper” are set in the physical arrangement table 21. Is done. Similarly for other smart meters 2, the combination of adjacent smart meters 2 is set in the physical arrangement table 21.

FIG. 8 is a diagram illustrating an example of the measurement information table 22. The measurement information table 22 illustrated in FIG. 8 is a table in which measurement information collected from each smart meter 2 is associated in units of smart meters 2, and for each “node ID”, “time”, “power amount”, and It includes information relating “current amount” to each other.

“Time” is information indicating the measurement time included in the measurement information, and “Power amount” is power amount data included in the measurement information. The power amount data is data indicating the amount of power used, which is the amount of power newly used in the consumer's electrical equipment 8, and is, for example, data per unit time Ta. “Current value” is current value data included in the measurement information. The current value data is data indicating the effective value of the current of the power line 4 measured every unit time Ta, for example.

In the example shown in FIG. 8, “P11_n” and “I11_n” are energy data and current value data at the time t_n of the consumer where the smart meter 2-11 is installed. “P11_n−1” and “I11_n−1” are power amount data and current value data at time t_n−1 of the consumer where the smart meter 2-11 is installed. Time t_n−1 is the time one time before time t_n. Similarly, the electric energy data and the current value data are set in the measurement information table 22 for the consumer in which each of the smart meters 2-12 to 2-2m is installed.

Although not shown, the measurement information table 22 includes demand data and high frequency data. The demand data is an electric power supplied to the consumer's electric equipment 8 and is an instantaneous value of the electric power measured every unit time Ta. The high frequency data is data indicating the effective value of the high frequency component of the current or voltage flowing through the power line 4. The measurement information may be stored in the storage unit 20 not in a table format such as the measurement information table 22 but in another format.

Further, the measurement information set in the measurement information table 22 is information used as meter-reading data, and is information collected periodically by the control unit 30. The unit time Ta can be set to the same time as the collection cycle Tc described later, and may be shorter than the collection cycle Tc. The measurement information set in the measurement information table 22 may be measurement information collected at a time different from the regular collection of measurement information used as meter reading data.

Next, returning to FIG. 6, the control unit 30 of the information collecting apparatus 1 will be described. The control unit 30 includes an information collection unit 31 that collects information from each of the smart meters 2, a route setting unit 32 that generates route information of each smart meter 2, and a load state of a consumer in which each smart meter 2 is installed. A load state monitoring unit 33 that monitors the route information table, and a route update unit 34 that updates the route information table.

The information collection unit 31 periodically transmits an information acquisition message for acquiring measurement information from each smart meter 2 to each smart meter 2 at the collection cycle Tc. The information collection unit 31 acquires measurement information transmitted from each smart meter 2 in response to the information acquisition message from the communication unit 10, stores the acquired measurement information in the storage unit 20, and updates the measurement information table 22. .

Further, when the communication unit 10 receives the S / N ratio together with the measurement information from the smart meter 2, the information collection unit 31 acquires the received S / N ratio from the communication unit 10, and acquires the acquired S / N ratio. The route candidate table 23 is updated by storing in the storage unit 20. In addition, when the communication unit 10 receives only measurement information from the smart meter 2, the information collection unit 31 acquires the S / N ratio calculated by the communication unit 10 when receiving the measurement information from the communication unit 10. The S / N ratio is stored in the storage unit 20 and the route candidate table 23 is updated.

The route candidate table 23 is generated based on the route information and S / N ratio acquired by the information collecting unit 31 from each smart meter 2-11 to 2-2m. Although there is no restriction on the method by which the information collection device 1 acquires route information to each smart meter 2, for example, as described in International Publication No. 2013/077700, route information is obtained by the following method. Can be acquired.

Each smart meter 2 broadcasts a proximity search request message as a new entry smart meter at the time of new entry. Each smart meter 2 transmits an entry request message to the information collection device 1 by using another smart meter 2 that has transmitted the proximity search response message in response to the proximity search request message as a next-hop node. The adjacent smart meter 2 that has received the entry request message transfers the entry request message to the next-hop smart meter 2 in the route to the information collection device 1 based on the route information that is held.

Thereafter, the smart meter 2 that has received the entry request message transfers the entry request message to the smart meter 2 of the next hop to the information collection device 1 based on the stored route information. Thereby, the entry request message arrives at the information collection device 1, and the information collection unit 31 of the information collection device 1 can acquire the route information of the new entry smart meter based on the entry request message.

Here, an example in which the smart meter 2-14 is a newly entered smart meter will be described with reference to FIGS. FIG. 9 is a diagram illustrating an example of a proximity search request message, and FIG. 10 is a diagram illustrating an example of a proximity search response message. 11 and 12 are diagrams illustrating an example of the entry request message.

The smart meter 2-14 broadcasts a proximity search request message shown in FIG. 9 as a request node for requesting participation. The adjacent smart meter 2-13 that has received the proximity search request message transmits a proximity search response message shown in FIG. 10 to the smart meter 2-14. The proximity search response message in FIG. 10 includes the S / N ratio when the smart meter 2-13 receives the proximity search request message, and the number of hops of the route from the smart meter 2-14 to the information collection device 1.

The smart meter 2-14 that has received the proximity search response message transmits an entry request message with the smart meter 2-13 as a transmission destination. As shown in FIG. 11, the entry request message includes the node ID of the requesting smart meter 2-14 and the S / N ratio when the smart meter 2-13 receives a proximity search request message.

When the smart meter 2-13 receives the entry request message from the smart meter 2-14, as shown in FIG. 12, the smart meter 2-13 adds an entry request message including the route specified by the stored route information as a source route to the next hop. To the smart meter 2-12. The smart meter 2-12 transfers the entry request message to the information collection device 1 based on the source route included in the entry request message or the stored route information. As will be described later, when the route information held in each smart meter 2 is only the node ID of the previous hop, the source route does not include the node ID of the information collection device 1 that is the node of the next hop. However, when the smart meter 2-12 transfers the entry request message, the node ID of the next hop node can be added to the source node.

The information collection unit 31 updates the route candidate table 23 stored in the storage unit 20 based on information included in the entry request message transmitted from each smart meter 2 and received by the communication unit 10. FIG. 13 is a diagram illustrating an example of a part of the route candidate table 23 including the route information acquired by the information collection device 1 based on the entry request message and the S / N ratio. In the route candidate table 23, information on route candidates that are route candidates is set.

The route candidate table 23 illustrated in FIG. 13 includes “next hop”, “measured S / N ratio”, “S / N ratio for route”, “number of hops”, and “route” for the node ID of each smart meter 2. Is information associated with each other. Hereinafter, when the route candidate table 23 is described, for convenience, a node in which the node ID is set in the “node ID” of the route candidate table 23 is referred to as a target node.

“Next hop” is the node ID of the smart meter 2 of the next hop of the target node on the route from the target node to the information collection device 1. A combination of the “node ID” and the “next hop” node shown in the route candidate table 23 is route candidate information that is a route candidate. The “measured S / N ratio” is the S / N ratio at the time of signal reception from the target node in the smart meter 2 at the next hop. "Route S / N ratio" is the S / N ratio used for route construction based on the measured S / N ratio, and "Hop number" is the number of hops to the information collection device 1 in the route candidate. . The “route” includes the node ID of the smart meter 2 that performs transfer to the information collection device 1.

When the route candidate table 23 is in the state shown in FIG. 13, for example, the smart meter 2-13 includes a route candidate that communicates directly with the information collection device 1, a route candidate that passes through the smart meter 2-11, and a smart meter. 2-12 route candidates are set. In FIG. 13, only the smart meters 2-11 to 2-1n are shown for simplification, and the smart meters 2-21 to 2-2m are omitted.

Referring back to FIG. 6, the description of the control unit 30 is continued. The route setting unit 32 of the control unit 30 determines the route of each smart meter 2 from the route candidates of each smart meter 2 included in the route candidate table 23, and stores the route information indicating the determined route in the route information storage area. 24.

Although there is no restriction on the method by which the information collection device 1 determines the route information of each smart meter 2, for example, a method as described in Japanese Patent Application Laid-Open No. 2015-220657, which is Patent Document 1, and S There is a hop number priority route construction method for selecting a route having a / N ratio larger than a predetermined value and a small number of hops. In the route construction method with priority on the number of hops, the route with the smallest hop number is selected from the routes with the S / N ratio larger than the threshold, and if there are a plurality of routes with the smallest hop number, the one with the larger S / N ratio is selected. Select a route.

FIG. 14 is a diagram illustrating an example of route information of each smart meter 2 determined by the route setting unit 32. The route information of each smart meter 2 shown in FIG. 14 is information in which “node ID”, “previous hop”, and “hop count” are associated with each other. In “Node ID”, the node ID of each smart meter 2 is set as the node ID of the target node. “Previous hop” is the node ID of the node immediately before the target node among the nodes included in the route toward the target node, and “Hop number” is the number of hops from the information collection device 1 to the target node. .

In the example shown in FIG. 14, one smart meter 2 is shown in one table, and the smart meter 2 table is displayed side by side for each number of hops. In the uppermost part of FIG. 14, route information of smart meters 2-11, 12-12 and 2-21 having a hop count of 1 is shown. The second row of FIG. 14 shows route information of smart meters 2-13, 2-14, 2-22, 2-23, and 2-24 with a hop count of two. The third row of FIG. 14 shows route information of smart meters 2-1n and 2-2m having a hop count of 3.

When transmitting a message to the smart meter 2, the control unit 30 of the information collection device 1 sets a route to the destination smart meter 2 as a source route based on the route information stored in the route information storage area 24. Obtain the source route in the message header. And the control part 30 transmits the message which stored the source route to the smart meter 2 of the next hop in a source route.

For example, when transmitting a message to the smart meter 2-1n, the control unit 30 refers to the route information of the left smart meter 2-1n in FIG. 2-14. Further, the control unit 30 refers to the route information of the smart meter 2-14 to grasp that the previous hop smart meter 2 is the smart meter 2-12, and further refers to the route information of the smart meter 2-12. It is understood that the previous hop node is the information collection device 1 which is the master unit of the PLC.

Thereby, the control unit 30 knows that the source route to the smart meter 2-1n is a route that is transferred in the order of the smart meter 2-12, the smart meter 2-14, and the smart meter 2-1n. Therefore, the control unit 30 stores this source route in the message addressed to the smart meter 2-1n and transmits it to the smart meter 2-12 at the next hop. The smart meter 2 that has received the message from the information collection device 1 refers to the source route stored in the message and performs transfer to the destination smart meter 2 according to the source route.

When a new entry smart meter, which is a new smart meter, is added to the PLC network, the control unit 30 of the information collection device 1 receives the entry request message from the new entry smart meter, and enters the source route stored. A response message is sent to the new entry smart meter. The new entry smart meter acquires and holds the route information to the information collection device 1 by the received entry response message.

FIG. 15 is a diagram showing an example of route information held by each smart meter 2, and shows an example of the smart meter 2-13. In the present embodiment, in order to minimize the route information held by each smart meter 2, the route information held by each smart meter 2 includes the node ID of the next hop smart meter 2 to the information collection device 1 and the information collection. Consists of the number of hops to device 1. Thus, each smart meter 2 holds the node ID of the smart meter 2 of the next hop to the information collection device 1 as route information, and does not need to hold route information to other smart meters 2.

When the smart meter 2 transmits a message addressed to the information collection device 1, the smart meter 2 transmits the message to the smart meter 2 of the next hop of the route information held by the own device. When the smart meter 2 receives a message addressed to the information collection device 1 from another smart meter 2, the smart meter 2 transfers the message to the next-hop smart meter 2 described in the route information held by the own device.

FIG. 16 is a diagram showing an example of an information request message transmitted from the information collecting apparatus 1 to the smart meter 2-1n. As shown in FIG. 16, in the data request message, the node ID of the information collecting apparatus 1 as a transmission source, the node ID of the smart meter 2-1n as the transmission destination, the number of hops from the transmission source to the transmission destination, Source route, message type, and payload are included.

Next, the operation in which the information collection device 1 collects measurement information from the smart meter 2 in the automatic meter reading system 100 according to the first embodiment will be described with reference to FIG. FIG. 17 is a UML (Unified Modeling Language) sequence diagram illustrating an operation example of the automatic meter reading system 100 according to the first embodiment.

In the example shown in FIG. 17, the control unit 30 of the information collection device 1 collects information such as measurement information and S / N ratio from each of the smart meters 2-11 to 2-2m, and routes based on the collected information. An example of the rebuilding operation is shown. As shown in FIG. 17, the control unit 30 of the information collecting apparatus 1 individually transmits information request messages from the communication unit 10 to the smart meters 2-11 to 2-2m, and the smart meters 2-11 to 2-2. The process of collecting measurement information and S / N ratio from -2m via the communication unit 10 is periodically executed at the collection cycle Tc.

Specifically, the control unit 30 of the information collection device 1 first generates an information request message addressed to the smart meter 2-11 and transmits it from the communication unit 10 (step S11). The smart meter 2-11 at the first hop from the information collecting apparatus 1 directly receives an information request message addressed to itself from the information collecting apparatus 1. When the smart meter 2-11 receives the information request message addressed to itself, it transmits the measurement information to the information collection device 1 (step S12).

The measurement information transmitted by the smart meter 2-11 to the information collecting device 1 is information including electrical information related to the power measured by the smart meter 2 and measurement time information indicating the time when the measurement was performed. As described above, the electrical information includes power amount data, demand data, current value data, high frequency data, and the like.

When receiving the measurement information from the smart meter 2-11 via the communication unit 10, the control unit 30 of the information collecting apparatus 1 associates the measurement information with the node ID of the smart meter 2-11 that is the transmission source of the measurement information. The measurement information table 22 is updated by storing in the storage unit 20. In addition, the information collection unit 31 of the information collection device 1 checks whether or not the S / N ratio is transmitted together with the measurement information. If the S / N ratio is not transmitted, the S / N is received when the measurement information is received. The ratio is calculated and updated by overwriting the measured S / N ratio in the route candidate table 23 shown in FIG. 13 with the calculated S / N ratio. The S / N ratio calculated when the information collection device 1 receives the measurement information corresponds to information indicating the communication quality between the information collection device 1 and the smart meter 2-11.

In the example shown in FIG. 17, when the control unit 30 of the information collection device 1 collects measurement information from the first hop smart meter 2-11, the S / N ratio is transmitted to the information collection device 1. Never come. Therefore, the control unit 30 of the information collection device 1 does not check whether or not the S / N ratio is transmitted together with the measurement information, but determines whether or not the smart meter 2 that is the transmission source of the measurement information is the first hop. If the transmission source is the smart meter 2 of the first hop, the measurement S / N ratio in the route candidate table 23 shown in FIG. 13 is updated with the S / N ratio calculated when the measurement information is received. Also good.

Next, the control unit 30 of the information collection device 1 generates an information request message addressed to the smart meter 2-12 and transmits it from the communication unit 10 (step S13). When the smart meter 2-12 receives the information request message addressed to its own device, the smart meter 2-12 transmits the measurement information to the information collecting device 1 (step S14).

When receiving the measurement information from the smart meter 2-12 via the communication unit 10, the control unit 30 of the information collecting apparatus 1 associates the measurement information with the node ID of the smart meter 2-12 that is the transmission source of the measurement information. Store and update the measurement information table 22. Further, the control unit 30 of the information collecting apparatus 1 checks whether or not the S / N ratio is transmitted together with the measurement information. If the S / N ratio is not transmitted, the S / N is received when the measurement information is received. The ratio is calculated and updated by overwriting the measured S / N ratio in the route candidate table 23 shown in FIG. 13 with the calculated S / N ratio. Next, the control unit 30 of the information collecting apparatus 1 executes the same operation as that performed on the smart meter 2-12 on the smart meter 2-13.

When acquiring the measurement information from the smart meter 2-13, the control unit 30 of the information collecting apparatus 1 generates an information request message addressed to the smart meter 2-13 and transmits it from the communication unit 10 (step S15). The smart meter 2-13 at the second hop from the information collecting device 1 receives the information request message addressed to the own device via the smart meter 2-12. When the smart meter 2-13 receives the information request message addressed to its own device, the smart meter 2-13 transmits the measurement information to the information collecting device 1 (step S16). The measurement information transmitted by the smart meter 2-13 is relayed by the smart meter 2-12 and then arrives at the information collection device 1.

The smart meter 2-12 that first transfers the measurement information transmitted by the smart meter 2-13, that is, the smart meter 2-12 that is one hop higher than the smart meter 2-13, transmits the measurement information. The S / N ratio calculated at the time of reception is added to the measurement information to be relayed. The S / N ratio added to the measurement information corresponds to information indicating the communication quality between the smart meter 2-12 and the smart meter 2-13.

When receiving the measurement information from the smart meter 2-13 via the communication unit 10, the control unit 30 of the information collection device 1 associates the measurement information with the node ID of the smart meter 2-13 that is the transmission source of the measurement information. And remember. In this case, since the control unit 30 of the information collecting apparatus 1 receives the S / N ratio together with the measurement information, the received S / N ratio is set to “N2-” in the “node ID” in the route candidate table 23 shown in FIG. 13 ”is updated by overwriting the“ measured S / N ratio ”of the route candidate whose“ next hop ”is“ N2-12 ”.

The control unit 30 of the information collection device 1 repeats the same processing, generates an information request message addressed to the smart meter 2-2m, and transmits it from the communication unit 10 (step S17). The control unit 30 of the information collecting apparatus 1 then transmits the measurement information transmitted from the smart meter 2-2m and the S / N ratio calculated by the smart meter 2-14 that relays the measurement information first, to the communication unit 10. (Step S18), the received measurement information and S / N ratio and the node ID of the smart meter 2-2m are stored in the storage unit 20 in association with each other, and the route candidate table 23 is updated.

When the control unit 30 of the information collection device 1 acquires the measurement information from all of the smart meters 2-11 to 2-2m, it uses the power amount data included in the collected measurement information of each smart meter 2 to use the load increase node A detection process (step S19) and a route reconstruction process (step S20) are performed. In addition, the process of the control part 30 in step S11 to step S18 mentioned above is a process which the information collection part 31 performs. As will be described later, the process of step S19 is executed by the load state monitoring unit 33, and the process of step S20 is executed by the route updating unit 34.

FIG. 18 is a flowchart showing an example of the load increase node detection process shown in step S19 of FIG. As shown in FIG. 18, the load state monitoring unit 33 of the control unit 30 selects one node as a selected node (step S21). The load state monitoring unit 33 acquires the measurement information associated with the node ID of the selected node from the measurement information table 22 as the measurement information of the selected node (Step S22).

The load state monitoring unit 33 determines whether or not the power amount data included in the measurement information of the selected node is greater than or equal to the threshold value Pth1 (step S23). When the load state monitoring unit 33 determines that the power amount data is not equal to or greater than the threshold value Pth1 (step S23: No), it determines whether the slope of the power amount data included in the measurement information of the selected node is equal to or greater than the threshold value ΔPth1. Determination is made (step S24). The inclination of the power amount data indicates an increase rate or an increase amount of the power amount data per unit time, and can be obtained based on, for example, the latest power amount data and the past power amount data before the previous time.

When the load state monitoring unit 33 determines that the power amount data is equal to or greater than the threshold value Pth1 (step S23: Yes), or when the slope of the power amount data is determined to be equal to or greater than the threshold value ΔPth1 (step S24: Yes), In order to accurately determine the possibility that a state where the communication quality of the PLC deteriorates due to an increase in load will occur, the process of step S25 is performed. The load state monitoring unit 33 determines whether or not the current value data included in the measurement information of the selected node is greater than or equal to the threshold value Ith1 in the process of step S25 (step S25).

When it is determined that the current value data is greater than or equal to the threshold value Ith1 (step S25: Yes), the load state monitoring unit 33 stores the selected node in the storage unit 20 as a load increase node (step S26). The load increase node is a smart meter 2 of a consumer who may be in a load state that generates noise having a magnitude that reduces communication quality in the PLC.

The load state monitoring unit 33 determines that the current value data is not equal to or greater than the threshold value Ith1 when the process of step S26 is completed (step S25: No), or that the slope of the power amount data is not equal to or greater than the threshold value ΔPth1. If so (step S24: No), it is determined whether or not all nodes have been selected as selected nodes (step S27).

When the load state monitoring unit 33 determines that all the nodes are not selected as the selected nodes (step S27: No), the unselected node is selected as the selected node (step S28), and the process proceeds to step S22. . Further, when it is determined that all nodes have been selected (step S27: Yes), the load state monitoring unit 33 ends the process illustrated in FIG.

The load state monitoring unit 33 uses the path update condition described above that the power amount data is greater than or equal to the threshold value Pth1 or the slope of the power amount data is greater than or equal to the threshold value ΔPth1 and the current value data is greater than or equal to the threshold value Ith1. The satisfying customer node is treated as a load increase node, but the route update condition is not limited to the above-described example. That is, the route update condition is at least one of the power amount data, the current value data, and the demand data so that the state in the previous stage of the state in which noise of a magnitude that degrades the communication quality in the PLC is generated can be detected. It only has to be included. Further, the route update condition may be a condition in which a condition for high-frequency data is further added.

For example, the load state monitoring unit 33 uses a path update condition that the slope of the current value data is greater than or equal to a threshold value ΔIth2 greater than the threshold value ΔIth1, or indicates that the slope of the power amount data is greater than or equal to a threshold value ΔPth2 greater than the threshold value ΔPth1 Update conditions. The slope of the current value data indicates an increase rate or an increase amount of the current value data per unit time, and can be obtained based on, for example, the latest current value data and past current value data before the previous time. Further, the load state monitoring unit 33 can also set the path update condition that the fluctuation pattern of the electric energy data, the fluctuation pattern of the current value data, and the like are preset fluctuation patterns.

As the collection period Tc, which is a period for collecting measurement information, is shorter, fluctuations in the electric energy data and fluctuations in the current value data can be analyzed with higher resolution. Therefore, the information collection unit 31 can shorten the collection period Tc when the period change condition that is a condition looser than the above-described path update condition is satisfied. Thereby, the detection accuracy of a load increase node can be improved.

FIG. 19 is a flowchart showing an example of the collection cycle changing process by the control unit 30. As illustrated in FIG. 19, the information collection unit 31 of the control unit 30 determines whether or not the state of the load on the consumer satisfies the cycle change condition (step S31). For example, the information collection unit 31 determines that the period change condition is satisfied when the power amount data is equal to or greater than the threshold value Pth3 smaller than the threshold values Pth1 and Pth2, or the current value data is equal to or greater than the threshold value Ith3 smaller than the threshold values Ith1 and Ith2. it can.

Cycle change condition is not limited to the above-mentioned example. That is, the cycle change condition is such that at least one of the electric energy data, the current value data, and the demand data is detected so that the state of the load can be detected in the previous stage of the state to be detected by the path change condition. What is necessary is just to include conditions.

When it is determined that the load state at the customer does not satisfy the cycle changing condition (step S31: No), the collection cycle Tc is set to the cycle T1 (step S32). The period T1 is, for example, 30 minutes. Moreover, when it determines with the state of the load in a consumer satisfying a period change condition (step S31: Yes), the collection period Tc is set to the period T2 (step S33). The period T2 is a period shorter than the period T1, for example, 1 minute.

When the process of step S32 or the process of step S33 is completed, the collection cycle changing process shown in FIG. 19 is terminated. The information collection unit 31 can perform the collection cycle changing process described above for each customer. As a result, the measurement information collection cycle Tc can be changed for each smart meter 2. In the above-described collection cycle changing process, the collection cycle Tc is switched between the cycle T1 and the cycle T2. However, the collection cycle Tc is changed so that the collection cycle Tc is shortened stepwise or continuously as the power amount data increases. Alternatively, the collection cycle Tc may be a short cycle stepwise or continuously as the current value data increases.

Note that the above-described route update condition and cycle change condition can be changed for each smart meter 2. The load state monitoring unit 33 determines the load variation pattern of each consumer based on the past measurement information stored in the storage unit 20, and the route update condition and the period change condition based on the determined load variation pattern. Can be set for each consumer. The load state monitoring unit 33 can also set a route update condition and a period change condition for each type of smart meter 2. In this way, by changing the route update condition and the period change condition for each customer or for each type of smart meter 2, the load increase node can be determined with higher accuracy.

Moreover, the load state monitoring unit 33 can predict the future load state of each customer based on the measurement information stored in the storage unit 20. For example, the load state monitoring unit 33 may predict a time period in which noise of a magnitude that degrades the communication quality in the PLC occurs, such as a time period in which the amount of power used increases greatly in a short time in each consumer. it can. Note that the load state monitoring unit 33 can improve the prediction accuracy by predicting the above-described time zone based on the measurement information collected when the collection cycle Tc is the cycle T2. The load state monitoring unit 33 can determine, as a load increase node, the smart meter 2 installed in a consumer whose time until the predicted time zone is within a preset range.

Next, the route reconstruction process in step S20 shown in FIG. 17 will be described. FIG. 20 is a flowchart illustrating an example of a route reconstruction process executed by the control unit 30. As shown in FIG. 20, the route update unit 34 of the control unit 30 determines whether or not there is a load increase node among all the nodes (step S40).

When it is determined that there is a load increasing node (step S40: Yes), the route update unit 34 performs route reconstruction with priority to the S / N ratio (step S41), and when it is determined that there is no load increasing node (step S40). : No), a route reconstruction process with priority on the number of hops is performed (step S42).

FIG. 21 is a flowchart showing an example of the route reconstruction process with priority on the S / N ratio. As illustrated in FIG. 21, the route update unit 34 performs a bypass route creation process for creating a bypass route table of the load increase node (step S <b> 51). The bypass route creation process in step S51 is the process in steps S61 to S66 shown in FIG. 22, and will be described later.

Next, the route update unit 34 changes the S / N ratio change processing for changing the route S / N ratio associated with the route candidate in which the combination of the bypass route of the load increasing node and the node ID matches in the route candidate table 23. Is performed (step S52). The S / N ratio changing process in step S52 is the process in steps S71 to S75 shown in FIG. 24 and will be described later.

Next, the route updating unit 34 performs route rebuilding processing for rebuilding a route based on the route candidate table 23 subjected to the S / N ratio change processing (step S53). The route reconstruction process in step S53 is the process in steps S81 to S88 shown in FIG. 26 and will be described later.

20 is performed by the route updating unit 34. The route rebuilding processing with priority on the number of hops in step S42 shown in FIG. The route rebuilding process with priority on the number of hops is a process of performing the process of step S53 without performing the processes of steps S51 and S52 in the route rebuilding process with priority on the S / N ratio.

FIG. 22 is a flowchart showing an example of the bypass route table creation process of the load increase node in step S51 shown in FIG. As illustrated in FIG. 22, the path update unit 34 acquires the node ID of one load increase node from the storage unit 20 (step S61).

Next, the path update unit 34 extracts the node ID of the higher-order node of the load increase node from the physical arrangement table 21 (Step S62). The higher-order node is a node where the connection position of the power line 3 is adjacent on the information collecting apparatus 1 side. When the physical arrangement table 21 is in the state shown in FIG. 7 and the load increase node is a node with the node ID “N2-13”, the upper node of the load increase node is the node with the node ID “N2-12”. It is.

Next, the path update unit 34 extracts the node ID of the lower node of the load increase node from the physical arrangement table 21 (step S63). The lower side node is a node where the connection position of the power line 3 is adjacent to the information collecting apparatus 1 on the opposite side. When the physical arrangement table 21 is in the state shown in FIG. 7 and the node has the node ID “N2-13”, the lower node of the load increase node is the node with the node ID “N2-14”.

Next, the route update unit 34 sets the bypass route in which the upper node and the lower node are associated with each other as the bypass route of the load increasing node in the bypass route table of the load increasing node (step S64). The path updating unit 34 determines whether or not the processing of steps S62 to S64 has been completed for all load increasing nodes (step S65). When it is determined that the processing of steps S62 to S64 has not been completed for all load increasing nodes (step S65: No), the route updating unit 34 determines the next load increasing node that has not performed the processing of steps S62 to S64. The node ID is acquired from the storage unit 20 (step S66), and the processes of steps S62 to S64 are executed.

When the route update unit 34 determines that the processing of steps S62 to S64 has been completed for all load increase nodes (step S65: Yes), the processing of FIG. As a result, the bypass paths of all the load increase nodes are set in the bypass path table of the load increase node, and the bypass path table of the load increase node is completed. The bypass route table of the load increase node is stored in the storage unit 20 by the route update unit 34.

FIG. 23 is a diagram illustrating an example of the bypass route table of the load increase node. The bypass route table 25 illustrated in FIG. 23 includes information on the bypass route of each load increasing node. The bypass path of the load increase node is indicated by a combination of the node ID of the upper node and the node ID of the lower node. In the bypass path table of the load increase node, the “first node” is the upper node It is the node ID, and “second node” is the node ID of the lower node.

The bypass route table 25 shown in FIG. 23 shows an example when the node IDs of the load increase nodes are “N2-11” and “N2-13”. That is, a combination of the node ID “N1” of the upper node of the load increasing node and the node ID “N2-12” of the lower node of the load increasing node as a bypass path of the load increasing node of the node ID “N2-11” Is set in the bypass route table 25. Further, as a bypass path of the load increasing node with the node ID “N2-13”, the node ID “N2-12” of the upper node of the load increasing node and the node ID “N2-14” of the lower node of the load increasing node Are set in the bypass route table 25.

FIG. 24 is a flowchart showing an example of the S / N ratio change process in step S52 of FIG. As illustrated in FIG. 24, the route update unit 34 selects one node ID as a selected node ID (step S71). The path updating unit 34 determines whether there is a bypass path having a combination of node IDs that matches the path candidate of the selected node ID (step S72).

In step S <b> 72, the route update unit 34 determines whether or not the route candidate of “node ID” that matches the selected node ID is set as the bypass route set in the bypass route table 25 in the route candidate table 23. To do.

For example, assume that the selected node ID is “N2-12”, the route candidate table 23 is in the state shown in FIG. 13, and the bypass route table 25 is in the state shown in FIG. In this case, the route candidate table 23 includes a combination of the node ID “N2-12” and the node ID “N1”, the node ID “N2-12”, and the node as the route candidates with the selected node ID “N2-12”. The combination of ID “N2-11” is included. The bypass route table 25 includes a combination of the node ID “N2-12” and the node ID “N1” as the bypass route. Therefore, in this case, the path update unit 34 determines that there is a bypass path having a combination of node IDs that matches the path candidate of the selected node ID.

When the path update unit 34 determines that there is a bypass path having a combination of node IDs that matches the path candidate of the selected node ID (step S72: Yes), the same node as the bypass path of the selected node ID The route S / N ratio associated with the ID combination route candidate is lowered by the predetermined value Vsn (step S73).

When the process of step S73 ends, or when the path update unit 34 determines that there is no bypass path with a combination of node IDs that matches the path candidate of the selected node ID (step S72: No), all It is determined whether or not the processing of step S72 is completed for the node ID (step S74). When it is determined that the process of step S72 has not been completed for all node IDs (step S74: No), the route update unit 34 selects a node ID that has not been subjected to the process of step S72 ( Step S75), the process proceeds to step S72.

If the route update unit 34 determines that the process of step S72 has been completed for all node IDs (step S74: Yes), the process of FIG. As a result, the S / N ratio for the route associated with the route candidate having the same node ID combination as the bypass route of each load increasing node among the route candidates in the route candidate table 23 is lowered by the predetermined value Vsn.

Here, it is assumed that the route candidate table 23 is in the state shown in FIG. 13 and the bypass route table 25 is in the state shown in FIG. In this case, the path candidate of the combination of the node ID “N1” and the node ID “N2-12” and the path candidate of the combination of the node ID “N2-12” and the node ID “N2-14” are associated with each other. The route S / N ratio is lowered by a predetermined value Vsn.

Assuming that Vsn = 30, the route candidate table 23 changes from the state shown in FIG. 13 to the state shown in FIG. FIG. 25 is a diagram illustrating an example of the route candidate table 23 when the route S / N ratio is changed. In the example shown in FIG. 25, the route S / N ratio of the route candidate of the combination of the node ID “N2-12” and the node ID “N1” is changed from “75” to “45”, and the node ID “N2- The S / N ratio for the route candidate of the combination of “14” and the node ID “N2-12” is changed from “76” to “46”.

FIG. 26 is a flowchart showing an example of the route reconstruction process in step S53 of FIG. As shown in FIG. 26, the route updating unit 34 selects one node ID as a target node (step S81). The route update unit 34 extracts one or more route candidates whose route S / N ratio is greater than the threshold value Vth from the route candidates of the target node in the route candidate table 23 (step S82).

Next, the route update unit 34 extracts a route candidate having the smallest number of hops from the one or more route candidates extracted in step S82 (step S83). The route update unit 34 determines whether or not the number of route candidates extracted in step S83 is one (step S84). If the route update unit 34 determines that the number of route candidates extracted in step S83 is one (step S84: Yes), the route update unit 34 performs route setting processing for setting the extracted route candidate as the route of the target node (step S84). S85).

When the route update unit 34 determines that the number of route candidates extracted in step S83 is not one (step S84: No), the route S / N ratio is the largest among the plurality of route candidates extracted in step S83. A route setting process for setting the route candidate of the target node as the route of the target node is performed (step S86). When the process of step S85 is completed or when the process of step S86 is completed, the path update unit 34 determines whether the path setting process has been completed for all the nodes (step S87).

When it is determined that the route setting process has not been completed for all nodes (step S87: No), the route update unit 34 selects the next node that has not been subjected to the route setting process as a target node (step S88). Then, the process proceeds to step S82. If the path update unit 34 determines that the path setting process has been completed for all nodes (step S87: Yes), the process of FIG. 26 ends.

By the above processing, the route is reconstructed with the route S / N ratio of the route bypassing the load increase node being reduced, so the route via the load increase node is set without bypassing the load increase node. Will come to be. Therefore, even if the noise that travels from the power line 4 to the power line 3 of the customer where the load increase node is installed increases and the communication environment in the PLC deteriorates, the load increase node is relayed without bypassing the load increase node. Therefore, it is possible to suppress a decrease in communication quality in the PLC.

Here, the node ID of the load increase node is “N2-13”, and the route candidate table 23 in which the route candidate table 23 is changed from the state shown in FIG. 13 to the state shown in FIG. 25 is processed in step S53 of FIG. The case where it is used in will be described. Further, it is assumed that Vth = 50.

First, the setting of the route of the node with the node ID “N2-12” will be described. As shown in FIG. 25, the route candidate of the node with the node ID “N2-12” is the first route candidate of the combination of the node ID “N2-12” and the node ID “N1”, and the node ID “N2-12”. ”And node ID“ N2-11 ”are two second route candidates.

The S / N ratio for the route of the first route candidate is “45”, which is smaller than the threshold value Vth. The S / N ratio for the route of the second route candidate is “80”, which is equal to or greater than the threshold value Vth. Therefore, the route update unit 34 sets the second route candidate as the route of the node having the node ID “N2-12”. The data whose source is the node with the node ID “N2-12” is transmitted to the node with the node ID “N2-11”, and transferred from the node with the node ID “N2-11” to the information collecting apparatus 1.

When the processing shown in FIG. 24 is not performed, the S / N ratio for the route of the first route candidate in the node with the node ID “N2-12” is “75”, which is the same as the measured S / N ratio, and the threshold value Vth or higher. For this reason, the first route candidate having a small number of hops is set as the route of the node having the node ID “N2-12”. Therefore, the data whose source is the node with the node ID “N2-12” is directly transferred to the information collecting apparatus 1 without going through the node with the node ID “N2-11”.

In this way, by performing the above-described change processing to the S / N ratio priority route, the node with the node ID “N2-11” is not bypassed without bypassing the node with the node ID “N2-11” that is the load increase node. The route that has passed is selected.

Next, the setting of the route of the node with the node ID “N2-14” will be described. As shown in FIG. 25, the route candidate of the node with the node ID “N2-14” is the first route candidate of the combination of the node ID “N2-14” and the node ID “N2-11”, and the node ID “N2- 14 ”and the node ID“ N2-12 ”combination of the second route candidate, and the node ID“ N2-14 ”and node ID“ N2-13 ”combination of the third route candidate.

The route S / N ratio of the first route candidate is “20”, which is smaller than the threshold Vth, and the route S / N ratio of the second route candidate is “46”, which is smaller than the threshold Vth. Although it is small, the S / N ratio for the route of the third route candidate is “75”, which is equal to or higher than the threshold value Vth. Therefore, the route update unit 34 sets the third route candidate as the route of the node having the node ID “N2-14”. The data whose source is the node with the node ID “N2-14” is transmitted to the node with the node ID “N2-13” and transferred to the information collecting apparatus 1 via the node with the node ID “N2-13”. Is done.

When the above-described change processing to the S / N ratio priority route is not performed, the S / N ratio for the route of the second route candidate in the node with the node ID “N2-14” is the same as the measured S / N ratio. Since “76” is equal to or greater than the threshold value Vth and is larger than the route S / N ratio of the third route candidate, the second route candidate is set as the route of the node having the node ID “N2-14”. Therefore, the data whose source is the node with the node ID “N2-14” is directly transferred to the information collecting apparatus 1 without going through the node with the node ID “N2-12”.

In this way, the route updating unit 34 increases the number of routes including the load increasing node, so that it is possible to increase the number of hops in the vicinity of a customer whose load may increase, and communication quality in the PLC Can be suppressed.

In the example described above, the route update unit 34 changes the route S / N ratio of the load increase node by lowering the route S / N ratio of the load increase node by the predetermined value Vsn. The change of the / N ratio is not limited to the example described above. For example, the route update unit 34 can set the route S / N ratio of the load increase node to a value equal to or less than the threshold value Vth. Thereby, it is possible to increase the number of routes including the load increase node with high accuracy. The path updating unit 34 can also increase the predetermined value Vsn as the power amount data or power value data increases. When the node that was the load increase node is no longer the load increase node, the route S / N ratio associated with the route candidate is changed by the route update unit 34 to the same value as the measured S / N ratio.

In the example described above, the route update unit 34 has changed the route S / N ratio of the load increase node, but may associate information indicating the load increase node with the route candidate in the route candidate table 23. In this case, the route update unit 34 can accurately increase the route including the load increase node by not setting the route candidate associated with the information indicating the load increase node as the route. Note that the route update unit 34 deletes the information indicating the load increase node associated with the route candidate when the node that was the load increase node is no longer the load increase node.

In the above-described example, the first S / N ratio that is the S / N ratio at the time of signal reception at the node on the path from the information collecting device 1 to the smart meter 2 is set as the “measurement S / N ratio”. However, the second S / N ratio that is the S / N ratio at the time of signal reception at the node on the path from the smart meter 2 to the information collecting device 1 can be set as the “measurement S / N ratio”. Further, an average value of the first S / N ratio and the second S / N ratio, or a value obtained by weighting and adding may be used as the “measurement S / N ratio”.

In the above example, the physical arrangement table 21 is set in advance, but the physical arrangement table 21 may be automatically generated by the control unit 30. For example, the control unit 30 can automatically generate the physical arrangement table 21 with a source having an S / N ratio for each source obtained by the proximity search response message shown in FIG. .

Here, the hardware configuration of the information collecting apparatus 1 according to the first embodiment will be described. FIG. 27 is a diagram of a hardware configuration example of the information collection device 1 according to the first embodiment. As illustrated in FIG. 27, the information collection device 1 includes a computer including a processor 201, a memory 202, and a communication device 203. The processor 201, the memory 202, and the communication device 203 can transmit / receive data to / from each other via the bus 204. The communication unit 10 of the information collection device 1 is realized by the communication device 203. The storage unit 20 of the information collection device 1 is realized by the memory 202. The memory 202 includes a recording medium on which a computer readable program is recorded.

The processor 201 reads out and executes the program stored in the memory 202, thereby executing the functions of the information collecting unit 31, the path setting unit 32, the load state monitoring unit 33, and the path updating unit 34. The processor 201 is an example of a processing circuit, and includes one or more of a CPU (Central Processing Unit), a DSP (Digital Signal Processor), and a system LSI (Large Scale Integration).

The memory 202 is a nonvolatile or volatile semiconductor such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), etc. Memory, magnetic disk, flexible disk, optical disk, compact disk, mini disk or DVD (Digital Versatile Disc).

The information collecting unit 31, the path setting unit 32, the load state monitoring unit 33, the path updating unit 34, and the storage unit 20 are dedicated hardware that realizes the same functions as the processor 201 and the memory 202 shown in FIG. It may be realized. The dedicated hardware is, for example, a single circuit, a composite circuit, a programmed processor, a processor programmed in parallel, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a processing circuit that combines these. is there. A part of the information collecting unit 31, the path setting unit 32, the load state monitoring unit 33, the path updating unit 34, and the storage unit 20 is realized by dedicated hardware, and the rest is processed by the processor 201 and the memory 202 shown in FIG. It may be realized.

As described above, the information collecting apparatus 1 according to the first embodiment performs multi-hop communication using the smart meter 2 and the power line 3 that are installed in each of a plurality of consumers and measure electrical information related to the power of the consumers. Do. The information collection device 1 includes an information collection unit 31 that acquires measurement information that is a measurement result of electrical information from the smart meter 2, a load state monitoring unit 33 that monitors a load state of a consumer based on the measurement information, a load And a route update unit 34 for updating a route in multi-hop communication based on the state of By monitoring the state of the load, the state in which the communication quality in the PLC may be lowered is grasped in advance, and before the communication quality in the PLC is lowered, between the information collecting apparatus 1 and each smart meter 2 The route can be reconstructed. Thereby, the fall of the communication quality in PLC can be suppressed.

Further, the load state monitoring unit 33 detects a customer satisfying a route update condition in which a load state is set in advance among a plurality of customers. The route update unit 34 can increase the number of routes including the smart meter 2 installed in a customer who satisfies the route update condition. Thereby, for example, the number of hops can be increased in the vicinity of a customer whose load has increased, and it is possible to suppress a decrease in communication quality in the PLC.

In addition, the route update unit 34 adds a route to the next smart meter, which is the smart meter 2 physically adjacent to the target smart meter 2 that is the smart meter 2 installed in the consumer that satisfies the route update condition, via the power line 3. Inclusion of the target smart meter increases the number of routes including the target smart meter. Thereby, for example, a combination between a load increasing node and a node adjacent to the load increasing node can be included in the route, and deterioration in communication quality in the PLC can be more accurately suppressed.

The information collection device 1 is second communication quality information for route selection set based on a measured S / N ratio, which is an example of first communication quality information indicating communication quality between smart meters 2. A storage unit 20 is provided for storing a route candidate table 23 having a route S / N ratio. The route update unit 34 changes the route S / N ratio between the smart meters 2 adjacent to the load increase node, and the route of the smart meter 2 adjacent to the load increase node based on the changed route S / N ratio. To change. Thereby, in the information collection device 1 that performs route update processing for selecting a route using the S / N ratio, the route update processing can be performed by adding the route S / N ratio. 1 development cost can be suppressed.

Also, the information collection unit 31 shortens the collection period Tc, which is a period for acquiring measurement information, based on the load state of the consumer. By shortening the collection cycle Tc, it is possible to analyze the load state of the consumer with high resolution. Thereby, when the state of the load on the consumer is a state to be analyzed with high resolution, the state of the load on the consumer can be analyzed with high resolution.

Also, the load state monitoring unit 33 can predict the load state of the consumer. The route update unit 34 updates the route based on the load state predicted by the load state monitoring unit 33. Therefore, for example, by predicting a time zone in which the amount of power used greatly increases in a short time in each consumer, for example, it is possible to avoid the occurrence of a processing load due to processing for monitoring the load state in real time. .

Embodiment 2. FIG.
The second embodiment is different from the first embodiment in that a process for updating a route is added so that a route that bypasses an adjacent node that is a node adjacent to the load increase node is not formed. In the following, constituent elements having the same functions as those in the first embodiment are denoted by the same reference numerals, description thereof is omitted, and differences from the information collecting apparatus 1 in the first embodiment are mainly described.

FIG. 28 is a diagram illustrating a configuration example of the information collection apparatus according to the second embodiment of the present invention. As shown in FIG. 28, the information collection apparatus 1A according to the second embodiment has a function of updating a route so that a route that bypasses a node adjacent to the load increase node is not formed in addition to the function of the route update unit 34. The route update unit 34A is provided.

FIG. 29 is a flowchart of an example of a route reconstruction process with priority on the S / N ratio according to the second embodiment. The processes in steps S101 and S104 shown in FIG. 29 are the same as the processes in steps S51 and S53 shown in FIG.

As shown in FIG. 29, when the route updating unit 34A completes the process of step S101, it creates a bypass route table for creating a bypass route table of an adjacent node, which is a node adjacent to the higher side and the lower side, in each load increasing node. Processing is performed (step S102). The bypass route creation process in step S102 is the process in steps S111 to S117 shown in FIG. 30, and will be described later.

Next, the path update unit 34A selects a path S associated with a path candidate whose node ID combination matches one of the bypass path of the load increasing node and the bypass path of the adjacent node in the path candidate table 23. An S / N ratio changing process for changing the / N ratio is performed (step S103). The S / N ratio changing process of step S103 is the process of steps S121 to S125 shown in FIG. 31, and will be described later.

FIG. 30 is a flowchart showing an example of the bypass route table creation process of the adjacent node in step S102 shown in FIG. As illustrated in FIG. 30, the path update unit 34A acquires the node ID of one load increase node from the storage unit 20 (step S111).

Next, the path update unit 34A extracts the node ID of the adjacent node that is the node adjacent to the load increase node from the physical arrangement table 21 (step S112). Specifically, in step S112, the route updating unit 34A determines the node ID of the upper side adjacent node that is the upper side node of the load increasing node and the node ID of the lower side adjacent node that is the lower side of the load increasing node. To extract.

Next, the path update unit 34A extracts the node ID of the higher-order node of the adjacent node from the physical arrangement table 21 (step S113). Further, the path updating unit 34A extracts the node ID of the lower side node of the adjacent node from the physical arrangement table 21 (step S114). Then, the path updating unit 34A sets a bypass path in which the higher order node and the lower order node of the adjacent node are associated with each other as a bypass path of the adjacent node in the bypass path table of the adjacent node (Step S115).

Here, if the load increase node is the node having the node ID “N-13”, the route updating unit 34A extracts the node ID “N-12” as the node ID of the upper side adjacent node in step S112, The node ID “N-14” is extracted as the node ID of the side adjacent node. In step S113, the path updating unit 34A extracts “N-11” as the node ID of the upper side node of the upper side adjacent node. In step S114, the path updating unit 34A uses the node ID of the lower side node of the upper side node as the node ID of the lower side node. The ID “N-13” is extracted.

In step S114, the route updating unit 34A extracts “N-13” as the node ID of the upper node of the lower neighbor node, and as the node ID of the lower node of the lower neighbor node in step S114. , “N−1n” are extracted. It is assumed that the node with the node ID “N−1n” is adjacent to the node with the node ID “N-14”.

Then, the path updating unit 34A sets the bypass path of the combination of the node ID “N-11” and the node ID “N-13” in the bypass path table of the adjacent node as the bypass path of the upper side adjacent node. Further, the path updating unit 34A sets the bypass path of the combination of the node ID “N-13” and the node ID “N-1n” as the bypass path of the lower side adjacent node in the bypass path table of the adjacent node.

The path updating unit 34A can also set a bypass path, which is a combination of the node ID of the higher-order node of the higher-order adjacent node and the node ID of the lower-order node of the lower-order adjacent node, in the bypass path table of the adjacent node. . For example, a combination of the node ID “N-11” and the node ID “N-1n” can be set in the bypass path table of the adjacent node.

The route updating unit 34A determines whether or not the processing in steps S112 to S115 has been completed for all nodes adjacent to the load increase node (step S116). If the path updating unit 34A determines that the processing of steps S112 to S115 has not been completed for all the nodes adjacent to the load increase node (step S116: No), the next load that has not performed the processing of steps S112 to S115. The node ID of the increased node is acquired from the storage unit 20 (step S117), and the processes of steps S112 to S115 are executed.

If the route update unit 34A determines that the processing in steps S112 to S115 has been completed for all nodes adjacent to the load increase node (step S116: Yes), the processing in FIG. 30 ends. Thereby, the bypass route of the adjacent node which is a node adjacent to all the load increase nodes is set in the bypass route table, and the bypass route table of the adjacent node is completed. The bypass route table of the adjacent node is stored in the storage unit 20 by the route update unit 34A.

FIG. 31 is a flowchart showing an example of the S / N ratio changing process in step S113 of FIG. Note that the processing in steps S121 and S123 to S125 shown in FIG. 31 is the same as the processing in steps S71 and S73 to S75 shown in FIG.

In step S122 shown in FIG. 31, the route updating unit 34A selects a node that matches the route candidate of the selected node ID among the bypass routes included in the bypass route table of the load increase node and the bypass route table of the adjacent node. It is determined whether there is a bypass path with a combination of IDs.

When the path update unit 34A determines that there is a bypass path having a combination of node IDs that matches the path candidate of the selected node ID (step S122: Yes), the same node as the bypass path of the selected node ID The route S / N ratio associated with the route combination of the ID combination is lowered by the predetermined value Vsn (step S123).

Thereby, since the S / N ratio for the route candidate that bypasses the adjacent nodes adjacent to the higher side and the lower side of the load increasing node is lowered, the number of routes including the adjacent node can be increased. Therefore, the number of hops can be further increased in the vicinity of a customer whose load has increased, and it is possible to suppress a decrease in communication quality in the PLC.

The route update unit 34A described above performs processing for lowering the route S / N ratio by the predetermined value Vsn. Similar to the processing of the route update unit 34, the route S / N ratio of the load increase node is less than or equal to the threshold value Vth. It can also be set to a value. Further, similarly to the route update unit 34, the route update unit 34 </ b> A can also associate information indicating the load increase node with the route candidate in the route candidate table 23.

The hardware configuration example of the information collecting apparatus 1A according to the second embodiment is the same as the information collecting apparatus 1 shown in FIG. The processor 201 can execute the function of the path updating unit 34A by reading and executing the program stored in the memory 202.

As described above, the path updating unit 34A of the information collection apparatus 1A according to the second embodiment sets the adjacent node in the path of the node that is physically adjacent to the adjacent node that is an example of the adjacent smart meter via the power line 3. Inclusion increases the number of routes that include neighboring smart meters. As a result, in addition to the load increasing node, the route can be updated so as not to bypass the neighboring smart meter, the number of hops can be further increased in the vicinity of the customer with increased load, and the communication quality in the PLC is lowered. This can be further suppressed.

Note that the route update unit 34A can increase the number of nodes that are the targets of the bypass route as the predicted load on the consumer increases. For example, the path updating unit 34A can also update the path by creating a bypass path that bypasses a node further adjacent to the adjacent node adjacent to the load increase node.

In addition, the route update unit 34A combines the two nodes selected from the node adjacent to the upper side adjacent node and the node adjacent to the upper side adjacent node into the bypass node of the adjacent node. Alternatively, the node ID of one of the upper side neighboring nodes can be used. For example, the path updating unit 34A can set a combination of the node ID of the higher-order node of the higher-order neighboring node and the node ID of the lower-order neighboring node in the bypass path table of the neighboring node. For example, in the above example, the path updating unit 34A can set the combination of the node ID “N-11” and the node ID “N-14” in the bypass path table of the adjacent node. The path updating unit 34A can also set a combination of the node ID of the upper side adjacent node and the node ID of the lower side node of the lower side adjacent node in the bypass path table of the adjacent node. For example, in the case of the above-described example, the path updating unit 34A can set the combination of the node ID “N-12” and the node ID “N−1n” in the bypass path table of the adjacent node.

The configuration described in the above embodiment shows an example of the contents of the present invention, and can be combined with another known technique, and can be combined with other configurations without departing from the gist of the present invention. It is also possible to omit or change the part.

1, 1A information collection device, 2, 2-11, 12-12, 2-13, 2-14, ..., 2-1n, 2-21, 22-22, 2-23, 2-24, ... ..., 2-2m smart meter, 3,3-1,3-2,4,4-11,4-12,4-13,4-14, ..., 4-1n, 4-21,4 -22, 4-23, 4-24, ..., 4-2m power line, 5 measuring terminals, 6 PLC slave module, 8, 8-1, 8-2, ..., 8-k electrical equipment, 10, 63 communication unit, 20, 42, 52, 62 storage unit, 21 physical arrangement table, 22 measurement information table, 23 route candidate table, 24 route information storage area, 25 bypass route table, 30, 53, 61 control unit, 31 Information collection unit, 32 route setting unit, 33 load status monitoring unit, 34, 3 A route updating unit, 51 measurement unit, 100 an automatic meter reading system.

Claims

In an information collecting apparatus that performs multi-hop communication using a smart meter and a power line that is installed in each of a plurality of consumers and measures electrical information related to the power of the consumers,
An information collection unit for obtaining measurement information that is a measurement result of the electrical information from the smart meter;
Based on the measurement information, a load state monitoring unit that monitors a load state in the consumer,
A route updating unit that updates a route in the multi-hop communication based on the state of the load.
The load state monitoring unit
Detecting a customer satisfying a route update condition in which a load state is set in advance among the plurality of consumers;
The route update unit
The information collection device according to claim 1, wherein the number of routes including a smart meter installed in a customer who satisfies the route update condition is increased.
The route update unit
By including the target smart meter in the path of a target smart meter that is a smart meter installed in a consumer that satisfies the path update condition and a neighboring smart meter that is physically adjacent to the smart meter via the power line. The information collection device according to claim 2, wherein the number of routes including the target smart meter is increased.
The route update unit
The number of paths including the neighboring smart meter is increased by including the neighboring smart meter in a path of a smart meter that is physically adjacent to the neighboring smart meter via the power line. The information collecting apparatus according to claim 3.
A storage unit for storing a route candidate table having second communication quality information for route selection set based on first communication quality information indicating communication quality between the smart meters;
The route update unit
The second communication quality information between the neighboring smart meters is changed, and the route of the neighboring smart meter is updated based on the changed second communication quality information. Information collection device.
The information collecting unit
6. The information collection device according to claim 1, wherein a period for acquiring the measurement information is shortened based on a state of the load.
The load state monitoring unit
Predicting the state of load at the consumer;
The route update unit
The information collection apparatus according to claim 1, wherein the route is updated based on the predicted state of the load.
A smart meter that is installed in each of a plurality of consumers and measures electrical information related to the power of the consumers;
An information collection device that performs multi-hop communication using the smart meter and a power line, and collects measurement information including a measurement result of the electrical information,
The information collecting device includes:
An information collecting unit for obtaining the measurement information from the smart meter;
Based on the measurement information, a load state monitoring unit that monitors a load state in the consumer,
An automatic meter-reading system comprising: a route updating unit that updates a route in the multi-hop communication based on the state of the load.
A device for performing multi-hop communication using a smart meter and a power line that is installed in each of a plurality of consumers and measures electrical information related to the power of the consumer and a route update method for updating a route in the multi-hop communication. ,
Obtaining measurement information including measurement results of the electrical information from the smart meter;
Monitoring the state of the load on the consumer based on the measurement information;
Updating the route in the multi-hop communication based on the state of the load.