Centralized direct current energy consumption device control method and device

Abstract

The invention discloses a centralized direct-current energy consumption device control method and device. The method comprises the steps that it is determined that a centralized direct-current energy consumption device enters a hot standby voltage-sharing state for voltage-sharing control; according to the following mode, each power module in the centralized direct-current energy consumption device is subjected to timing polling, and each polling period during timing polling comprises a waiting stage and a polling stage: in the polling stage, the power modules in normal states are subjected to short-time triggering, and the power modules in abnormal states are subjected to fault processing; and in the waiting stage, short-time triggering is not executed until the polling cycle is ended. The method is used for ensuring that the power module in the centralized direct-current energy consumption device can be in a good energy-consuming state at any time, and the reliability of the centralized direct-current energy consumption device is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power equipment control, and in particular to a centralized direct current energy consumption device control method and device. Background Art

[0002] This section is intended to provide a background or context to the embodiments of the invention recited in the claims. No admission is made that the description herein is prior art by inclusion in this section.

[0003] Flexible direct current transmission technology (Voltage Source Converter based High Voltage Direct Current Transmission, VSC-HVDC) can realize the transmission of offshore wind power. When the offshore wind power is transmitted by AC grid connection, due to the large inertia characteristics of wind power, when the onshore converter station fails, the power transmitted by the offshore converter station cannot be adjusted quickly, resulting in overvoltage of the DC bus. The configuration of DC energy dissipation devices on the DC side of the onshore converter station can effectively suppress the overvoltage of the DC bus. When the DC bus is overvoltage, the DC energy dissipation device can quickly absorb the surplus function of the DC bus and realize fault ride-through.

[0004] The DC energy consumption device will only be put into use when a fault occurs in the flexible DC system causing the DC bus voltage to increase, and it will be in hot standby mode for the rest of the time. In the hot standby mode, the DC energy consumption device will perform voltage equalization control and send a trigger pulse to the power module in a higher voltage sequence to reduce its capacitor voltage. For centralized DC energy consumption devices in direct series, if the trigger time during the voltage equalization control process lasts too long, it will cause excessive energy loss. Therefore, the voltage equalization control of the centralized DC energy consumption device will set a very short trigger pulse duration, but this may cause the capacitor voltage of some power modules to always be in the lowest voltage sequence. These power modules will not be triggered to turn on and will be in the off state all year round. It is impossible to determine whether the power module has a fault, resulting in a decrease in the reliability of the centralized DC energy consumption device. Summary of the invention

[0005] An embodiment of the present invention provides a centralized DC energy consumption device control method for ensuring that a power module in the centralized DC energy consumption device can be in a good energy consumption state at any time, thereby improving the reliability of the centralized DC energy consumption device. The method includes:

[0006] Determine that the centralized DC energy consumption device enters the hot standby voltage balancing state to perform voltage balancing control;

[0007] In the following manner, each power module in the centralized DC energy consumption device is polled regularly, wherein each polling cycle of the regular polling includes a waiting phase and a polling phase:

[0008] In the polling phase, the power modules in normal state are triggered for a short time, and the power modules in abnormal state are fault-handled;

[0009] During the waiting phase, no short-term triggering is performed until the polling cycle ends.

[0010] The embodiment of the present invention further provides a centralized DC energy consumption device control device, which is used to ensure that the power modules in the centralized DC energy consumption device can be in a good energy consumption state at any time, thereby improving the reliability of the centralized DC energy consumption device. The device includes:

[0011] A state judgment module is used to determine whether the centralized DC energy consumption device enters the hot standby voltage balancing state to perform voltage balancing control;

[0012] The timing polling control module is used to perform timing polling on each power module in the centralized DC energy consumption device in the following manner, wherein each polling cycle during the timing polling includes a waiting phase and a polling phase:

[0013] In the polling phase, the power modules in normal state are triggered for a short time, and the power modules in abnormal state are fault-handled;

[0014] During the waiting phase, no short-term triggering action is executed until the polling cycle ends.

[0015] An embodiment of the present invention further provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned centralized DC energy consumption device control method when executing the computer program.

[0016] An embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the above-mentioned centralized DC energy consumption device control method is implemented.

[0017] An embodiment of the present invention further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the centralized DC energy consumption device control method is implemented.

[0018] The prior art adopts a technical solution based on the capacitor voltage sorting of power modules to preferentially trigger power modules with higher voltages, but some power modules may not be triggered due to their lower capacitor voltage sorting, and it is impossible to determine whether these power modules are faulty. Compared with the prior art, the embodiment of the present invention performs regular polling on each power module in the centralized DC energy consumption device, so that each power module can be regularly triggered for a short time, and the power module with abnormal status can be promptly processed to prevent affecting the performance and reliability of the centralized DC energy consumption device, and ensure that when the centralized DC energy consumption device needs to be put into use, all power modules are in a good energy-consuming state, thereby improving the reliability of the centralized DC energy consumption device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] 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 prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0020] Figure 1 Schematic diagram of a centralized DC energy consumption device in an embodiment of the present invention;

[0021] Figure 2 is a processing flow chart of a centralized DC energy consumption device control method according to an embodiment of the present invention;

[0022] Figure 3 It is a flow chart of a centralized DC energy consumption device entering a hot standby voltage balancing state in an embodiment of the present invention;

[0023] Figure 4 This is a timing polling workflow diagram of a power module of a centralized DC energy consumption device in an embodiment of the present invention;

[0024] Figure 5 Schematic diagram of a centralized DC energy consumption device control device in an embodiment of the present invention. DETAILED DESCRIPTION

[0025] To make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. Here, the exemplary embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0026] In the hot standby voltage balancing state, the centralized DC energy consumption device will control the voltage balancing of the power modules to keep the power modules in an energy-consuming state. Figure 1 Schematic diagram of a centralized DC energy consumption device in an embodiment of the present invention. Figure 1 As shown, Udc is the DC bus voltage, "+" represents the positive pole, "-" represents the negative pole, I m is the current through the DC energy consuming device, SM 1 , SM 2 , SM 3 , …, SM n It is the power module in the DC energy consumption device, R m It is an energy-consuming resistor. However, the existing voltage-sharing control strategy for centralized DC energy-consuming devices is based on the capacitor voltage ranking of power modules, and the power modules with higher voltages are triggered first. This may cause some power modules with lower capacitor voltage rankings to not be triggered for a long time and remain in the off state all year round. It is still unclear whether the power modules that have not been triggered for a long time are faulty.

[0027] In order to avoid failure of some components inside certain modules of a centralized DC energy consumption device and ensure that the DC energy consumption device is in a good energy-consuming state at any time, an embodiment of the present invention proposes a centralized DC energy consumption device control method, so that the centralized DC energy consumption device can also perform periodic trigger tests on each power module in the DC energy consumption device in a hot standby voltage balancing state, thereby ensuring that the power module can be put into normal use when an AC fault occurs, thereby improving the reliability of the centralized DC energy consumption device. Figure 2 FIG. 1 is a processing flow chart of a centralized DC energy consumption device control method according to an embodiment of the present invention. Figure 2 As shown, the method comprises the following steps:

[0028] Step 201, determine that the centralized DC energy consumption device enters the hot standby voltage balancing state to perform voltage balancing control;

[0029] Step 202: Perform regular polling on each power module in the centralized DC energy consumption device in the following manner, wherein each polling cycle during the regular polling includes a waiting phase and a polling phase:

[0030] In the polling phase, the power modules in normal state are triggered for a short time, and the power modules in abnormal state are fault-handled;

[0031] During the waiting phase, no short-term triggering is performed until the polling cycle ends.

[0032] In one embodiment, determining that a centralized DC energy consumption device enters a hot standby voltage balancing state for voltage balancing control includes: after the centralized DC energy consumption device receives an unlocking command issued by a flexible DC control protection unit, determining that the centralized DC energy consumption device enters a hot standby voltage balancing state for voltage balancing control.

[0033] In one embodiment, before the centralized DC energy consumption device receives the unlocking command issued by the flexible DC control protection unit, the following states of the centralized DC energy consumption device are monitored: the centralized DC energy consumption device sends a self-test normal signal to the flexible DC control protection unit; the centralized DC energy consumption device performs uncontrolled charging on the power module through the DC bus; the centralized DC energy consumption device enters controlled charging after the uncontrolled charging is completed; the centralized DC energy consumption device sends a valve group ready signal to the flexible DC control protection unit after the controlled charging is completed.

[0034] The centralized DC energy consumption device control method in the embodiment of the present invention is for the centralized DC energy consumption device in the hot standby voltage balancing state, through the timing polling mechanism, so that all power modules in the centralized DC energy consumption device can be triggered in a short time. In some embodiments, certain conditions are required before the centralized DC energy consumption device enters the hot standby voltage balancing state: first, it will go through two stages of uncontrolled charging and controlled charging to ensure that the initial energy of the centralized DC energy consumption device is maintained at an appropriate level; then, the DC energy consumption device will wait for the flexible DC unlocking command; once this command is received, the centralized DC energy consumption device will officially enter the hot standby voltage balancing state. Figure 3 Flow chart of the centralized DC energy consumption device entering the hot standby voltage balancing state in the embodiment of the present invention. The DC energy consumption device needs to execute the following steps: Figure 3 The steps shown below are to enter the hot standby voltage balancing state:

[0035] Step 301: The centralized DC energy consumption device sends a self-check normal signal to the flexible DC control protection unit;

[0036] Step 302: The centralized DC energy consumption device performs uncontrolled charging on the power module via the DC bus;

[0037] Step 303: After the uncontrolled charging of the centralized DC energy consumption device is completed, the controlled charging begins;

[0038] Step 304: After the centralized DC energy consumption device is completed in controlled charging, a valve group ready signal is sent to the flexible DC control protection unit;

[0039] Step 305, determining whether an unlock command is received from the flexible DC control protection unit; if an unlock command is received, executing step 306; if no unlock command is received, continuing to execute step 305;

[0040] Step 306: The DC energy consumption device enters the hot standby voltage balancing state to perform voltage balancing control.

[0041] For example, for a half-bridge modular multilevel converter (MMC converter), when the AC circuit breaker of the onshore converter station is closed, a voltage will be established on the DC bus, and the DC energy consumption device connected to the DC bus will be charged uncontrolled. After the uncontrolled charging is completed, the DC energy consumption device automatically enters the controllable charging state to further increase the voltage of the power module in the DC energy consumption device. After the controlled charging is completed, it waits for the flexible DC unlocking command from the flexible DC control protection unit. When the onshore converter station is unlocked, the DC energy consumption device enters the hot standby voltage balancing state (hot standby state) and enters the voltage balancing control stage.

[0042] In an embodiment of the present invention, each power module in a centralized DC energy consumption device is polled periodically in the following manner, wherein each polling cycle during the periodic polling includes a waiting stage and a polling stage: in the polling stage, a short-time trigger is performed on a power module in a normal state, and a fault processing is performed on a power module in an abnormal state; in the waiting stage, a short-time trigger is not performed until the polling cycle ends.

[0043] In one embodiment, in the polling stage, the power modules in normal state are short-term triggered, including: in the polling stage, each power module in normal state is short-term triggered in turn according to a predetermined multiple of the hot standby voltage balancing cycle.

[0044] In one embodiment, during the polling stage, a power module in normal status is short-term triggered, and a power module in abnormal status is fault-handled, including: during the polling stage, the status flag of the power module is read; a power module in normal status is short-term triggered, and a power module in abnormal status is fault-handled.

[0045] In one embodiment, reading a status flag of a power module includes: reading a bypass switch status of the power module.

[0046] After the centralized DC energy consumption device enters the hot standby voltage balancing state, in some embodiments, each power module in the centralized DC energy consumption device is polled periodically. Figure 4 FIG. 1 is a timing polling workflow diagram of a power module of a centralized DC energy consumption device in an embodiment of the present invention. For example, the bypass switch state of a power module represents its state flag (for example, if the bypass switch is closed, it represents that the state flag is a fault). Figure 4 As shown in the figure, the timing polling process of the power module in the centralized DC energy consumption device is as follows:

[0047] Step 401, performing regular polling on the power modules in the centralized DC energy consumption device;

[0048] Step 402, determining whether the bypass switch of the power module being polled is closed; if the bypass switch is in a closed state, executing step 403, otherwise executing step 404;

[0049] Step 403: do not send a trigger pulse, perform fault processing, and execute step 405;

[0050] Step 404: Send a trigger pulse to trigger the power module for a short time, and execute step 405;

[0051] Step 405 , determining whether the polling cycle is over; if it is determined that the polling cycle is not over, executing step 405 , otherwise executing step 401 for the next power module.

[0052] For example, in a certain engineering project, the hot standby voltage balancing cycle is 5ms. First, the polling cycle between power modules is set to 33,000 times the voltage balancing control cycle, that is, 33,000×5ms=165s; wait for the centralized DC energy consumption device to enter the hot standby voltage balancing state, and perform regular polling on each power module in the centralized DC energy consumption device, with a polling cycle of 165s. That is, the time period for completing a poll for all power modules is: the product of the number of power modules and 33,000 times the voltage balancing control cycle. For example: if the total number of power modules is 524, the regular polling cycle of a power module is 524×(33,000×5ms)≈24h. Therefore, starting from the first power module, approximately every 24 hours, 524 power modules can be triggered for a short time in sequence. The timing polling trigger pulse width is 500 μs, that is, in the polling cycle of the power module: the polling stage takes 500 μs, and the waiting stage takes 33000×5ms-500 μs.

[0053] The present invention also provides a centralized DC energy consumption device control device, as described in the following embodiments. Since the principle of solving the problem by the device is similar to that of the centralized DC energy consumption device control method, the implementation of the device can refer to the implementation of the centralized DC energy consumption device control method, and the repeated parts will not be repeated.

[0054] Figure 5 Schematic diagram of a centralized DC energy consumption device control device in an embodiment of the present invention. Figure 5 As shown, the device comprises:

[0055] A state judgment module 501 is used to determine whether the centralized DC energy consumption device enters a hot standby voltage balancing state to perform voltage balancing control;

[0056] The timing polling control module 502 is used to perform timing polling on each power module in the centralized DC energy consumption device in the following manner, wherein each polling cycle during the timing polling includes a waiting phase and a polling phase:

[0057] In the polling phase, the power modules in normal state are triggered for a short time, and the power modules in abnormal state are fault-handled;

[0058] During the waiting phase, no short-term triggering action is executed until the polling cycle ends.

[0059] In one embodiment, the state determination module 501 is specifically used to:

[0060] After the centralized DC energy consumption device receives the unlocking command sent by the flexible DC control protection unit, it is determined that the centralized DC energy consumption device enters the hot standby voltage balancing state to perform voltage balancing control.

[0061] In one embodiment, the state determination module 501 is further used to:

[0062] Before the centralized DC energy consumption device receives the unlocking command issued by the flexible DC control protection unit, the following states of the centralized DC energy consumption device are monitored:

[0063] The centralized DC energy consumption device sends a self-check normal signal to the flexible DC control protection unit;

[0064] The centralized DC energy consumption device charges the power module uncontrolled via the DC bus;

[0065] After the centralized DC energy consumption device completes uncontrolled charging, it enters controlled charging;

[0066] After the centralized DC energy consumption device completes controllable charging, a valve group ready signal is sent to the flexible DC control protection unit.

[0067] In one embodiment, the timing polling control module 502 is specifically used to: in the polling stage, short-term trigger each power module in normal state in turn according to a predetermined multiple of the hot standby voltage balancing cycle.

[0068] In one embodiment, the timing polling control module 502 is specifically used to: read the status flag of the power module during the polling phase;

[0069] A power module whose status mark indicates that the power module is in a normal state is triggered for a short time, and a power module whose status mark indicates that the power module is in an abnormal state is fault-handled.

[0070] In one embodiment, the timing polling control module 502 is specifically used to read the bypass switch status of the power module during the polling phase.

[0071] An embodiment of the present invention further provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned centralized DC energy consumption device control method when executing the computer program.

[0072] An embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the above-mentioned centralized DC energy consumption device control method is implemented.

[0073] An embodiment of the present invention further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the centralized DC energy consumption device control method is implemented.

[0074] In an embodiment of the present invention, it is determined that the centralized DC energy consumption device enters the hot standby voltage balancing state to perform voltage balancing control; each power module in the centralized DC energy consumption device is polled regularly in the following manner, wherein each polling cycle during the regular polling includes a waiting stage and a polling stage: in the polling stage, a short-time trigger is performed on the power module in normal state, and a fault handling is performed on the power module in abnormal state; in the waiting stage, a short-time trigger is not performed until the polling cycle ends. Compared with the technical solution in the prior art that uses capacitor voltage sorting based on power modules and preferentially triggers power modules with higher voltages, the embodiment of the present invention performs regular polling on each power module in the centralized DC energy consumption device, so that each power module can be short-time triggered regularly, and the power module in abnormal state can be handled in time to prevent it from affecting the performance and reliability of the centralized DC energy consumption device, ensuring that all power modules are in a good energy-consuming state when the centralized DC energy consumption device needs to be put into use, thereby improving the reliability of the centralized DC energy consumption device.

[0075] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0076] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0077] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0078] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0079] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A centralized DC energy consumption device control method, characterized in that: include: Determine that the centralized DC energy consumption device enters the hot standby voltage balancing state to perform voltage balancing control; In the following manner, each power module in the centralized DC energy consumption device is polled regularly, wherein each polling cycle of the regular polling includes a waiting phase and a polling phase: In the polling phase, the power modules in normal state are triggered for a short time, and the power modules in abnormal state are fault-handled; During the waiting phase, no short-term triggering is performed until the polling cycle ends.

2. The centralized DC energy consumption device control method according to claim 1, characterized in that: Determine that the centralized DC energy consumption device enters the hot standby voltage balancing state to perform voltage balancing control, including: After the centralized DC energy consumption device receives the unlocking command sent by the flexible DC control protection unit, it is determined that the centralized DC energy consumption device enters the hot standby voltage balancing state to perform voltage balancing control.

3. The centralized DC energy consumption device control method according to claim 2, characterized in that: Also includes: Before the centralized DC energy consumption device receives the unlocking command issued by the flexible DC control protection unit, the following states of the centralized DC energy consumption device are monitored: The centralized DC energy consumption device sends a self-check normal signal to the flexible DC control protection unit; The centralized DC energy consumption device charges the power module uncontrolled via the DC bus; After the centralized DC energy consumption device completes uncontrolled charging, it enters controlled charging; After the centralized DC energy consumption device completes controllable charging, a valve group ready signal is sent to the flexible DC control protection unit.

4. The centralized DC energy consumption device control method according to claim 1, characterized in that: During the polling phase, the power modules in normal state are triggered for a short time, including: In the polling stage, each power module in a normal state is triggered for a short time in turn according to a predetermined multiple of the hot standby voltage balancing cycle.

5. The centralized DC energy consumption device control method according to claim 1, characterized in that: During the polling phase, the power modules in normal state are triggered for a short time, and the power modules in abnormal state are fault-handled, including: In the polling phase, the status flag of the power module is read; A power module whose status mark indicates that the power module is in a normal state is triggered for a short time, and a power module whose status mark indicates that the power module is in an abnormal state is fault-handled.

6. The centralized DC energy consumption device control method according to claim 5, characterized in that: Read the status flags of the power module, including: Read the bypass switch status of the power module.

7. A centralized DC energy consumption device control device, characterized in that: include: A state judgment module is used to determine whether the centralized DC energy consumption device enters the hot standby voltage balancing state to perform voltage balancing control; The timing polling control module is used to perform timing polling on each power module in the centralized DC energy consumption device in the following manner, wherein each polling cycle during the timing polling includes a waiting phase and a polling phase: In the polling phase, the power modules in normal state are triggered for a short time, and the power modules in abnormal state are fault-handled; During the waiting phase, no short-term triggering action is executed until the polling cycle ends.

8. The device according to claim 7, characterized in that The status judgment module is specifically used for: After the centralized DC energy consumption device receives the unlocking command sent by the flexible DC control protection unit, it is determined that the centralized DC energy consumption device enters the hot standby voltage balancing state to perform voltage balancing control.

9. The device according to claim 8, characterized in that The status judgment module is also used for: Before the centralized DC energy consumption device receives the unlocking command issued by the flexible DC control protection unit, the following states of the centralized DC energy consumption device are monitored: The centralized DC energy consumption device sends a self-check normal signal to the flexible DC control protection unit; The centralized DC energy consumption device charges the power module uncontrolled via the DC bus; After the centralized DC energy consumption device completes uncontrolled charging, it enters controlled charging; After the centralized DC energy consumption device completes controllable charging, a valve group ready signal is sent to the flexible DC control protection unit.

10. The device according to claim 7, characterized in that The timing polling control module is specifically used to: in the polling stage, according to the predetermined multiples of the hot standby voltage balancing cycle, short-term trigger each power module in normal state in turn.

11. The device according to claim 7, characterized in that The timing polling control module is specifically used to: read the status flag of the power module during the polling phase; A power module whose status mark indicates that the power module is in a normal state is triggered for a short time, and a power module whose status mark indicates that the power module is in an abnormal state is fault-handled.

12. The device according to claim 11, characterized in that The timing polling control module is specifically used to read the bypass switch state of the power module during the polling stage.

13. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 6 is implemented.

14. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

15. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

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