Low-voltage distribution network distributed monitoring method, system, terminal and storage medium

Abstract

The present invention relates to the field of power supply technology, and specifically provides a low-voltage distribution network distributed monitoring method, system, terminal and storage medium, including: monitoring the voltage amplitude information of the load end of the low-voltage distribution network; using a pre-trained neural network model to identify the topology of the low-voltage distribution network based on the voltage amplitude; generating a superior-subordinate relationship between the monitoring devices according to the topology and a pre-set binding relationship between the monitoring device and the topology node; generating a communication link list according to the superior-subordinate relationship between the monitoring devices, the communication link list including information on establishing a communication link between the lower-level monitoring device and the upper-level monitoring device; sending the communication link list to monitoring devices at all levels to establish a communication link between the monitoring devices, so that the monitoring devices receive monitoring messages from the lower-level monitoring devices through the communication links, and upload the monitoring message processing results to the upper-level monitoring devices. The present invention reduces the workload of the monitoring center and integrates power grid monitoring.

Description

Technical Field

[0001] The present invention relates to the field of power supply technology, and in particular to a distributed monitoring method, system, terminal and storage medium for a low-voltage distribution network. Background Art

[0002] Power grid monitoring is a crucial data source for power supply network maintenance. Existing grid monitoring systems often rely on individual management nodes to monitor their respective areas, resulting in a lack of integrated monitoring across the entire region. In some cases, individual management nodes directly aggregate and report monitoring data to a monitoring center, significantly increasing the workload and placing high demands on its resources. Summary of the Invention

[0003] In response to the problems in the prior art that monitoring data cannot be integrated or the workload of monitoring data processing is too large, the present invention provides a low-voltage distribution network distributed monitoring method, system, terminal and storage medium to solve the above technical problems.

[0004] In a first aspect, the present invention provides a distributed monitoring method for a low-voltage distribution network, comprising:

[0005] Monitor the voltage amplitude information at the load end of the low-voltage distribution network;

[0006] Identifying a topology of a low-voltage distribution network based on the voltage amplitude using a pre-trained neural network model;

[0007] Generate a hierarchical relationship between monitoring devices based on the topological structure and a pre-set binding relationship between monitoring devices and topological nodes;

[0008] generating a communication link list according to the hierarchical relationship between the monitoring devices, the communication link list including information on establishing a communication link between the lower-level monitoring device and the upper-level monitoring device;

[0009] The communication link list is sent to monitoring devices at all levels to establish communication links between the monitoring devices, so that the monitoring devices receive monitoring messages from the next level monitoring devices through the communication links and upload the monitoring message processing results to the previous level monitoring devices.

[0010] Furthermore, the voltage amplitude information at the load end of the low-voltage distribution network is monitored, including:

[0011] The voltage amplitude of each load terminal is regularly monitored by a voltage sensor, and the voltage amplitudes monitored each time within a specified period are sorted in order of monitoring time to generate a voltage sequence;

[0012] The voltage sequence is subtracted from the standard voltage to obtain a characteristic sequence.

[0013] Furthermore, a pre-trained neural network model is used to identify the topology of the low-voltage distribution network based on the voltage amplitude, including:

[0014] Inputting the characteristic sequence into a neural network model to obtain the corresponding state of all line control switching in the low-voltage distribution network;

[0015] The physical line topology of the power grid is marked with the status of all line control switching, the electrical connection relationship of each node in the low-voltage distribution network is obtained, and the electrical connection relationship of each node is output as a topology structure.

[0016] Furthermore, based on the topological structure and the pre-set binding relationship between the monitoring devices and the topological nodes, a hierarchical relationship between the monitoring devices is generated, including:

[0017] Parsing the superior-subordinate relationship of topological nodes from the topological structure;

[0018] The topological nodes in the hierarchical relationship of the topological nodes are replaced with bound monitoring devices to obtain a hierarchical relationship between the monitoring devices, wherein the monitoring devices include a sensor group, a communication module and a monitoring processor.

[0019] In a second aspect, the present invention provides a low-voltage distribution network distributed monitoring system, comprising:

[0020] A load monitoring unit is used to monitor the voltage amplitude information at the load end of the low-voltage distribution network;

[0021] a topology identification unit, configured to identify a topology of a low-voltage distribution network based on the voltage amplitude using a pre-trained neural network model;

[0022] a level generating unit, configured to generate a hierarchical relationship between monitoring devices according to the topological structure and a pre-set binding relationship between monitoring devices and topological nodes;

[0023] a linked list generating unit, configured to generate a communication link list according to a superior-subordinate relationship between the monitoring devices, the communication link list including information on establishing a communication link between a subordinate monitoring device and a superior monitoring device;

[0024] The communication establishment unit is used to send the communication link list to monitoring devices at all levels to establish communication links between monitoring devices, so that the monitoring device can receive monitoring messages from the next level monitoring device through the communication link and upload the monitoring message processing results to the previous level monitoring device.

[0025] Furthermore, the load monitoring unit includes:

[0026] The periodic monitoring module is used to periodically monitor the voltage amplitude of each load terminal through a voltage sensor, and to generate a voltage sequence by arranging the voltage amplitudes monitored each time within a specified period according to the monitoring time;

[0027] The sequence generation module is used to obtain a characteristic sequence by subtracting the voltage sequence from the standard voltage.

[0028] Furthermore, the topology identification unit includes:

[0029] A state recognition module is used to input the feature sequence into a neural network model to obtain the corresponding state of all line control switching in the low-voltage distribution network;

[0030] The topology generation module is used to mark the physical line topology structure of the power grid with the status of all line control switching, obtain the electrical connection relationship of each node in the low-voltage distribution network, and output the electrical connection relationship of each node as a topology structure.

[0031] Furthermore, the level generating unit includes:

[0032] A topology parsing module, configured to parse the superior-subordinate relationship of topological nodes from the topological structure;

[0033] The node replacement module is used to replace the topological nodes in the superior-subordinate relationship of the topological nodes with bound monitoring devices to obtain the superior-subordinate relationship between the monitoring devices. The monitoring devices include a sensor group, a communication module and a monitoring processor.

[0034] According to a third aspect, a terminal is provided, including:

[0035] processor, memory, wherein

[0036] The memory is used to store computer programs,

[0037] The processor is used to call and run the computer program from the memory, so that the terminal executes the above-mentioned terminal method.

[0038] In a fourth aspect, a computer storage medium is provided, wherein the computer-readable storage medium stores instructions, which, when executed on a computer, enable the computer to execute the methods described in the above aspects.

[0039] The beneficial effects of the present invention lie in the fact that the method, system, terminal, and storage medium for distributed monitoring of a low-voltage distribution network provided herein identify the grid topology and establish hierarchical relationships between monitoring devices based on this grid topology, thereby establishing communication links between the monitoring devices based on this hierarchical relationship. This allows monitoring data to be reported and processed layer by layer, with only the most important data processing results reported to the top-level monitoring center, significantly reducing the workload of the monitoring center and completing the integration of grid monitoring.

[0040] In addition, the present invention has a reliable design principle, a simple structure and a very broad application prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0042] Figure 1 is a schematic flow chart of a method according to an embodiment of the present invention.

[0043] Figure 2 FIG. 4 is a schematic block diagram of a system according to an embodiment of the present invention.

[0044] Figure 3 A schematic diagram of the structure of a terminal provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0046] Figure 1 is a schematic flow chart of a method according to an embodiment of the present invention. Figure 1 The execution entity may be a distributed monitoring system for a low-voltage distribution network.

[0047] like Figure 1 As shown, the method includes:

[0048] Step 110, monitoring voltage amplitude information at a load end of a low-voltage distribution network;

[0049] Step 120, using a pre-trained neural network model to identify the topology of the low-voltage distribution network based on the voltage amplitude;

[0050] Step 130: Generate a hierarchical relationship between monitoring devices based on the topological structure and the pre-set binding relationship between monitoring devices and topological nodes;

[0051] Step 140: Generate a communication link list based on the hierarchical relationship between the monitoring devices, wherein the communication link list includes information on establishing a communication link between the lower-level monitoring device and the upper-level monitoring device;

[0052] Step 150: Send the communication link list to monitoring devices at all levels to establish communication links between monitoring devices, so that the monitoring devices receive monitoring messages from the next level monitoring devices through the communication links and upload the monitoring message processing results to the previous level monitoring devices.

[0053] To facilitate understanding of the present invention, the following further describes the distributed monitoring method for a low-voltage distribution network provided by the present invention based on the principle of the distributed monitoring method for a low-voltage distribution network of the present invention and the process of performing distributed monitoring on a low-voltage distribution network in an embodiment.

[0054] Specifically, the low-voltage distribution network distributed monitoring method includes:

[0055] S1. Monitor the voltage amplitude information at the load end of the low-voltage distribution network.

[0056] A voltage sensor is installed at each load terminal connected to a load, such as the output terminal of a residential power supply. The voltage sensor regularly monitors the voltage amplitude at each load terminal. The voltage amplitudes monitored within a specified period are sorted by monitoring time to generate a voltage sequence [220v, 221v, 220v, 220v, 223v]. This voltage sequence is subtracted from the standard voltage to obtain a characteristic sequence [0, 1, 0, 0, 3].

[0057] S2. Using a pre-trained neural network model, identifying the topology of the low-voltage distribution network based on the voltage amplitude.

[0058] Neural networks (NNs) are complex network systems formed by a large number of simple processing units (called neurons) that are widely interconnected. They reflect many basic characteristics of human brain function and are highly complex nonlinear dynamic learning systems. Neural networks have large-scale parallel, distributed storage and processing, self-organization, self-adaptation, and self-learning capabilities. They are particularly suitable for handling imprecise and ambiguous information processing problems that require simultaneous consideration of many factors and conditions.

[0059] The present invention pre-constructs a neural network model, and the method for constructing the neural network model is prior art and therefore will not be described in detail.

[0060] The historical load-end voltage characteristic data and the corresponding grid switching status are collected, and the collected data are used as the training set and verification set to train and verify the neural network model to obtain a trained neural network model.

[0061] By inputting the feature sequence in step S1 into the neural network model, the control switching status of all lines in the power grid can be obtained.

[0062] A physical topology of the power grid is generated based on the physical connections of the power grid. The lines in this topology are labeled with switching states. The switching states output by the model are input into the topology. Lines with a switching state of connected are considered valid, while lines with a switching state of disconnected are considered invalid. By extracting all valid lines, a topology indicating the electrical connection relationships of each node is obtained.

[0063] S3. Generate a hierarchical relationship between the monitoring devices based on the topological structure and the pre-set binding relationship between the monitoring devices and the topological nodes.

[0064] Pre-bind the topology node and the monitoring device, and bind the topology node name with the corresponding monitoring device IP.

[0065] The superior-subordinate relationship of topological nodes is parsed from the topological structure. The superior-subordinate relationship between topological nodes is determined based on the connection relationship of the topological nodes in the topological structure. For example, the subordinate nodes of topological node A are topological nodes B and topological node C, and the subordinate node of topological node B is topological node D. Then topological node A is connected to topological node B and topological node C, and topological node B is connected to topological node D. The superior-subordinate relationship is determined based on the current flow in the power grid. The node closer to the input end is the superior node, and the node closer to the output end is the subordinate node.

[0066] The topological nodes in the superior-subordinate relationship of the topological nodes are replaced with bound monitoring devices to obtain the superior-subordinate relationship between the monitoring devices. In this embodiment, the monitoring device includes a sensor group, a communication module and a monitoring processor. The monitoring device can obtain monitoring information through the sensor group and can also obtain operation data through the interface connection topological node (scheduling node). Both monitoring information and operation data are reported as monitoring data.

[0067] S4. Generate a communication link list according to the superior-subordinate relationship between the monitoring devices, wherein the communication link list includes information on establishing a communication link between the subordinate monitoring device and the superior monitoring device.

[0068] For example, the subordinate monitoring devices of monitoring device A are monitoring device B and monitoring device C, and the subordinate node of monitoring device B is monitoring device D. Among them, the address of monitoring device A is IP1, the address of monitoring device B is IP2, the address of monitoring device C is IP3, and the address of monitoring device D is IP4. The linked list is constructed as follows:

[0069]

[0070]

[0071] S5. Send the communication link list to monitoring devices at all levels to establish communication links between monitoring devices, so that the monitoring device receives monitoring messages from the next level monitoring device through the communication link and uploads the monitoring message processing results to the previous level monitoring device.

[0072] The linked list generated in step S4 is sent to all monitoring devices. After receiving the linked list, the monitoring devices establish communication links according to the link information in the linked list.

[0073] A monitoring device receives monitoring messages from the next-level monitoring device via a communication link and uploads the results of the monitoring message processing to the next-level monitoring device. For example, monitoring device D performs a simple threshold comparison on its own monitoring data and uploads the comparison results to monitoring device B. Monitoring device B processes its own monitoring data and the comparison results of monitoring device B according to local processing rules and uploads the processing results to monitoring device A. Monitoring device A receives the data uploaded by monitoring devices B and C, and then uses local processing rules to process the monitoring data generated by monitoring devices B, C, and locally to obtain the final monitoring results. The processing rules for different monitoring devices can be set by the monitoring devices themselves or uniformly issued by the top-level monitoring center.

[0074] like Figure 2 As shown, the system 200 includes:

[0075] The load monitoring unit 210 is used to monitor the voltage amplitude information at the load end of the low-voltage distribution network;

[0076] a topology identification unit 220 for identifying a topology of a low-voltage distribution network based on the voltage amplitude using a pre-trained neural network model;

[0077] A level generating unit 230 is configured to generate a hierarchical relationship between monitoring devices according to the topological structure and a pre-set binding relationship between monitoring devices and topological nodes;

[0078] a link list generating unit 240 for generating a communication link list according to the hierarchical relationship between the monitoring devices, the communication link list including information for establishing a communication link between the lower-level monitoring device and the upper-level monitoring device;

[0079] The communication establishment unit 250 is used to send the communication link list to monitoring devices at all levels to establish communication links between monitoring devices, so that the monitoring device can receive monitoring messages from the next level monitoring device through the communication link and upload the monitoring message processing results to the previous level monitoring device.

[0080] Optionally, as an embodiment of the present invention, the load monitoring unit includes:

[0081] The periodic monitoring module is used to periodically monitor the voltage amplitude of each load terminal through a voltage sensor, and to generate a voltage sequence by arranging the voltage amplitudes monitored each time within a specified period according to the monitoring time;

[0082] The sequence generation module is used to obtain a characteristic sequence by subtracting the voltage sequence from the standard voltage.

[0083] Optionally, as an embodiment of the present invention, the topology identification unit includes:

[0084] A state recognition module is used to input the feature sequence into a neural network model to obtain the corresponding state of all line control switching in the low-voltage distribution network;

[0085] The topology generation module is used to mark the physical line topology structure of the power grid with the status of all line control switching, obtain the electrical connection relationship of each node in the low-voltage distribution network, and output the electrical connection relationship of each node as a topology structure.

[0086] Optionally, as an embodiment of the present invention, the level generating unit includes:

[0087] A topology parsing module, configured to parse the superior-subordinate relationship of topological nodes from the topological structure;

[0088] The node replacement module is used to replace the topological nodes in the superior-subordinate relationship of the topological nodes with bound monitoring devices to obtain the superior-subordinate relationship between the monitoring devices. The monitoring devices include a sensor group, a communication module and a monitoring processor.

[0089] Figure 3 This is a structural diagram of a terminal 300 provided in an embodiment of the present invention. The terminal 300 can be used to execute the low-voltage distribution network distributed monitoring method provided in an embodiment of the present invention.

[0090] The terminal 300 may include a processor 310, a memory 320, and a communication unit 330. These components communicate via one or more buses. Those skilled in the art will appreciate that the server structure shown in the figure does not limit the present invention. The server structure may be a bus structure or a star structure, and may include more or fewer components than shown, or may combine certain components or arrange the components differently.

[0091] The memory 320 can be used to store execution instructions of the processor 310. The memory 320 can be implemented by any type of volatile or non-volatile storage terminal or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk, or optical disk. When the execution instructions in the memory 320 are executed by the processor 310, the terminal 300 can perform some or all of the steps in the following method embodiments.

[0092] The processor 310 is the control center of the storage terminal. It uses various interfaces and lines to connect various parts of the entire electronic terminal. It runs or executes software programs and / or modules stored in the memory 320, and calls data stored in the memory to perform various functions of the electronic terminal and / or process data. The processor can be composed of an integrated circuit (IC), for example, it can be composed of a single packaged IC, or it can be composed of multiple packaged ICs with the same or different functions. For example, the processor 310 can only include a central processing unit (CPU). In an embodiment of the present invention, the CPU can be a single computing core or multiple computing cores.

[0093] The communication unit 330 is configured to establish a communication channel so that the storage terminal can communicate with other terminals, receive user data sent by other terminals, or send user data to other terminals.

[0094] The present invention also provides a computer storage medium, wherein the computer storage medium may store a program that, when executed, may include some or all of the steps of each embodiment provided by the present invention. The storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM).

[0095] Therefore, the present invention identifies the power grid topology and establishes hierarchical relationships between monitoring devices based on this topology, thereby establishing communication links between the monitoring devices. This allows monitoring data to be reported and processed layer by layer, with only the most important data processing results reported to the top-level monitoring center. This significantly reduces the workload of the monitoring center and completes the integration of power grid monitoring. The technical effects achieved by this embodiment can be found in the description above and will not be repeated here.

[0096] Those skilled in the art will clearly understand that the technology in the embodiments of the present invention can be implemented by means of software plus a necessary general-purpose hardware platform. Based on this understanding, the technical solutions in the embodiments of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. The computer software product is stored in a storage medium such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, or other medium that can store program code, and includes a number of instructions for enabling a computer terminal (which can be a personal computer, a server, or a second terminal, a network terminal, etc.) to execute all or part of the steps of the method described in each embodiment of the present invention.

[0097] In this specification, the same or similar parts between the various embodiments can be referred to each other. In particular, for the terminal embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the description in the method embodiment.

[0098] In the several embodiments provided by the present invention, it should be understood that the disclosed systems and methods can be implemented in other ways. For example, the system embodiments described above are merely illustrative. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of systems or units, and can be electrical, mechanical or other forms.

[0099] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0100] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0101] Although the present invention has been described in detail with reference to the accompanying drawings and in combination with preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, a person of ordinary skill in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and such modifications or substitutions shall be within the scope of the present invention. Any person skilled in the art who is familiar with the present invention may easily conceive of changes or substitutions within the technical scope disclosed in the present invention, and such changes or substitutions shall be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A distributed monitoring method for a low-voltage distribution network, characterized in that: include: Monitor the voltage amplitude information at the load end of the low-voltage distribution network; Identifying a topology of a low-voltage distribution network based on the voltage amplitude using a pre-trained neural network model; Generate a hierarchical relationship between monitoring devices based on the topological structure and a pre-set binding relationship between monitoring devices and topological nodes; generating a communication link list according to the hierarchical relationship between the monitoring devices, the communication link list including information on establishing a communication link between the lower-level monitoring device and the upper-level monitoring device; Sending the communication link list to monitoring devices at all levels to establish communication links between the monitoring devices, so that the monitoring devices receive monitoring messages from the monitoring devices at the next level through the communication links, and upload monitoring message processing results to the monitoring devices at the previous level; Monitor the voltage amplitude information at the load end of the low-voltage distribution network, including: The voltage amplitude of each load terminal is regularly monitored by a voltage sensor, and the voltage amplitudes monitored each time within a specified period are sorted in order of monitoring time to generate a voltage sequence; Subtracting the voltage sequence from the standard voltage to obtain a characteristic sequence; Identifying the topology of the low-voltage distribution network based on the voltage amplitude using a pre-trained neural network model, including: Inputting the characteristic sequence into a neural network model to obtain the corresponding state of all line control switching in the low-voltage distribution network; The physical line topology of the power grid is marked with the status of all line control switching, the electrical connection relationship of each node in the low-voltage distribution network is obtained, and the electrical connection relationship of each node is output as a topology structure.

2. The method according to claim 1, characterized in that Generate a hierarchical relationship between monitoring devices based on the topological structure and the pre-set binding relationship between monitoring devices and topological nodes, including: Parsing the superior-subordinate relationship of topological nodes from the topological structure; The topological nodes in the hierarchical relationship of the topological nodes are replaced with bound monitoring devices to obtain a hierarchical relationship between the monitoring devices, wherein the monitoring devices include a sensor group, a communication module and a monitoring processor.

3. A distributed monitoring system for a low-voltage distribution network, characterized in that: include: A load monitoring unit is used to monitor the voltage amplitude information at the load end of the low-voltage distribution network; a topology identification unit, configured to identify a topology of a low-voltage distribution network based on the voltage amplitude using a pre-trained neural network model; a level generating unit, configured to generate a hierarchical relationship between monitoring devices according to the topological structure and a pre-set binding relationship between monitoring devices and topological nodes; a linked list generating unit, configured to generate a communication link list according to a superior-subordinate relationship between the monitoring devices, the communication link list including information on establishing a communication link between a subordinate monitoring device and a superior monitoring device; a communication establishing unit, configured to send the communication link list to monitoring devices at all levels to establish communication links between the monitoring devices, so that the monitoring devices receive monitoring messages from the monitoring devices at the next level through the communication links, and upload monitoring message processing results to the monitoring devices at the previous level; The load monitoring unit includes: The periodic monitoring module is used to periodically monitor the voltage amplitude of each load terminal through a voltage sensor, and to generate a voltage sequence by arranging the voltage amplitudes monitored each time within a specified period according to the monitoring time; A sequence generation module, configured to obtain a characteristic sequence by subtracting the voltage sequence from a standard voltage; The topology identification unit includes: A state recognition module is used to input the feature sequence into a neural network model to obtain the corresponding state of all line control switching in the low-voltage distribution network; The topology generation module is used to mark the physical line topology structure of the power grid with the status of all line control switching, obtain the electrical connection relationship of each node in the low-voltage distribution network, and output the electrical connection relationship of each node as a topology structure.

4. The system according to claim 3, characterized in that The level generating unit comprises: A topology parsing module, configured to parse the superior-subordinate relationship of topological nodes from the topological structure; The node replacement module is used to replace the topological nodes in the superior-subordinate relationship of the topological nodes with bound monitoring devices to obtain the superior-subordinate relationship between the monitoring devices. The monitoring devices include a sensor group, a communication module and a monitoring processor.

5. A terminal, characterized in that: include: processor; a memory for storing execution instructions of the processor; The processor is configured to execute the method according to any one of claims 1 to 2.

6. A computer-readable storage medium storing a computer program, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 2 is implemented.

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