Fault detection device, system and method for receiving laser of optical receiving board

Abstract

The present invention discloses a fault detection device, system and method for a receiving laser of an optical receiving board, the device comprising: a controller and a driving impedance; the controller is used to: after the transmitting laser emits an optical signal, receive an impedance value change command continuously sent by a host computer at preset time intervals; after receiving the driving impedance value change command each time, change the impedance value of the driving impedance once, so that the optical power of the transmitting laser is gradually reduced, and the driving impedance is used to drive the optical receiving board to work; after obtaining the optical receiving board displacement signal fed back by the receiving laser, feed it back to the host computer to trigger the host computer to stop sending the impedance value change command, and use the current impedance value as the impedance threshold; the optical receiving board displacement signal is fed back by the receiving laser after the receiving laser cannot recognize the optical signal; when the impedance threshold is less than the preset minimum impedance threshold, determine that the receiving laser is faulty. The present invention can effectively detect the fault of the receiving laser of the valve-controlled optical receiving board of the converter valve.

Description

Technical Field

[0001] The present invention relates to the technical field of high voltage direct current power transmission, and in particular to a fault detection device, system and method for a receiving laser of an optical receiving board. 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] In the high-voltage DC converter valve VBE equipment, there are generally multiple light receiving boards for receiving feedback signals from the valve tower thyristor. Figure 1 This is a simplified diagram of the optical circuit of an existing optical receiving board. The optical receiving board is used to detect the thyristor feedback signal of the valve tower and monitor the status of the thyristor based on the feedback signal. In the detection of existing optical receiving boards, the laser transmitter is generally detected, and the laser power emitted by the laser transmitter is monitored by an optical power meter to evaluate its quality, but there is almost no detection of the receiving laser. If the return optical signal is not received due to a failure or aging of the receiving laser of the optical receiving board during application, it will cause a system alarm, and in severe cases it may even cause the system to lock and trip. It can be seen that the detection of the receiving laser of the optical receiving board is also very necessary. Summary of the invention

[0004] An embodiment of the present invention provides a fault detection device for a receiving laser of an optical receiving board, which can effectively detect the fault of a receiving laser of a valve-controlled optical receiving board of a converter valve. The device includes:

[0005] Controller and driver impedance;

[0006] The controller is used to:

[0007] After the transmitting laser emits an optical signal, the impedance value change command continuously sent by the host computer at preset time intervals is received; each time the driving impedance value change command is received, the impedance value of the driving impedance is changed once, so that the optical power of the transmitting laser is gradually reduced, and the driving impedance is used to drive the light receiving board to work;

[0008] After obtaining the optical receiving board displacement signal fed back by the receiving laser, the signal is fed back to the host computer to trigger the host computer to stop issuing impedance value change commands and use the current impedance value as the impedance threshold; the optical receiving board displacement signal is fed back by the receiving laser after the optical signal cannot be recognized;

[0009] When the impedance threshold is less than a preset minimum impedance threshold, it is determined that the receiving laser fails.

[0010] The embodiment of the present invention also provides a fault detection system for a receiving laser of an optical receiving board, which can effectively detect the fault of a receiving laser of a valve-controlled optical receiving board of a converter valve, and the system includes: a host computer, the aforementioned device;

[0011] The host computer is used to continuously send impedance value change commands after the transmitting laser sends out an optical signal.

[0012] The embodiment of the present invention further provides a method for detecting a fault of a receiving laser of an optical receiving board, which is applied to the aforementioned device and can effectively detect a fault of a receiving laser of a valve-controlled optical receiving board of a converter valve. The method comprises:

[0013] After the transmitting laser emits an optical signal, the impedance value change command continuously sent by the host computer at preset time intervals is received; each time the driving impedance value change command is received, the impedance value of the driving impedance is changed once, so that the optical power of the transmitting laser is gradually reduced, and the driving impedance is used to drive the light receiving board to work;

[0014] After obtaining the optical receiving board displacement signal fed back by the receiving laser, the signal is fed back to the host computer to trigger the host computer to stop issuing impedance value change commands and use the current impedance value as the impedance threshold; the optical receiving board displacement signal is fed back by the receiving laser after the optical signal cannot be recognized;

[0015] When the impedance threshold is less than a preset minimum impedance threshold, it is determined that the receiving laser fails.

[0016] An embodiment of the present invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the fault detection method of the receiving laser of the above-mentioned optical receiving board when executing the computer program.

[0017] 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 fault detection method of the receiving laser of the optical receiving board is implemented.

[0018] 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 fault detection method of the receiving laser of the optical receiving board is implemented.

[0019] In the embodiment of the present invention, the controller controls the driving impedance of the laser transmitter continuously at preset time intervals, which equivalently realizes the continuous and smooth change of the optical power of the laser transmitter. After obtaining the optical receiving board displacement signal fed back by the receiving laser, it is fed back to the host computer. The optical receiving board displacement signal can trigger the host computer to stop issuing impedance value change commands, and obtain the current impedance value as the impedance threshold, which can be compared with the minimum impedance threshold to determine whether the receiving laser is faulty. The early screening of the receiving laser of the optical receiving board is realized, so as to intervene in the faulty receiving laser in advance to avoid operation with hidden dangers. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] 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:

[0021] Figure 1 A schematic diagram of an optical circuit of an existing light receiving board;

[0022] Figure 2 A schematic diagram of a fault detection device for a receiving laser of an optical receiving board in an embodiment of the present invention;

[0023] Figure 3 It is a light circuit connection diagram of the light receiving board in the embodiment of the present invention;

[0024] Figure 4 Schematic diagram of the optical power of the emitting laser, the impedance value of the driving impedance and the turning threshold value in an embodiment of the present invention;

[0025] Figure 5 It is a schematic diagram of the lateral comparison of the turning impedances of different receiving lasers in an embodiment of the present invention;

[0026] Figure 6 is a detailed schematic diagram of a fault detection device for a receiving laser of a light receiving board in an embodiment of the present invention;

[0027] Figure 7 Schematic diagram of an optical signal when abnormal in an embodiment of the present invention;

[0028] Figure 8 is a threshold impedance relationship diagram in an embodiment of the present invention;

[0029] Fig. 9 is a flow chart of a method for detecting a fault of a receiving laser of an optical receiving board in an embodiment of the present invention;

[0030] Fig.10Schematic diagram of a computer device in an embodiment of the present invention. DETAILED DESCRIPTION

[0031] 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.

[0032] First, the terms involved in the embodiments of the present invention are introduced.

[0033] FPGA: FPGA devices are a kind of semi-customized circuit in application-specific integrated circuits. They are programmable logic arrays that can effectively solve the problem of the small number of gate circuits in the original devices. The basic structure of FPGA includes programmable input and output units, configurable logic blocks, digital clock management modules, embedded block RAM, wiring resources, embedded dedicated hard cores, and bottom-level embedded functional units. FPGA has been widely used in the field of digital circuit design because of its rich wiring resources, reprogrammable and high integration, and low investment.

[0034] Digital Potentiometer: Digital Potentiometer, also known as digitally controlled programmable resistor, is a new type of CMOS digital and analog mixed signal processing integrated circuit that replaces the traditional mechanical potentiometer (analog potentiometer). The digital potentiometer is controlled by digital input and produces an analog output. Depending on the digital potentiometer, the maximum value of the tap current can range from hundreds of microamperes to several milliamperes. The digital potentiometer uses digital control to adjust the resistance value. It has significant advantages such as flexible use, high adjustment accuracy, no contact, low noise, not easy to be contaminated, anti-vibration, anti-interference, small size, and long life. It can replace mechanical potentiometers in many fields.

[0035] SPI communication: SPI is the abbreviation of Serial Peripheral interface, which is a high-speed, full-duplex, synchronous communication bus. It only occupies four wires on the chip pins, saving the chip pins and saving space on the PCB layout, providing convenience. It is precisely because of this simple and easy-to-use feature that more and more chips integrate this communication protocol, mainly used in EEPROM, FLASH, real-time clock, AD converter, and between digital signal processors and digital signal decoders.

[0036] Serial port (COM port): Serial interface is also called serial communication interface or serial communication interface (usually refers to COM interface). It is an expansion interface that uses serial communication. Serial interface (Serial Interface) refers to the sequential transmission of data one bit at a time. Its characteristics are simple communication lines. Only one pair of transmission lines can realize two-way communication (telephone lines can be directly used as transmission lines), which greatly reduces costs. It is particularly suitable for long-distance communication, but the transmission speed is slow.

[0037] Host computer: The host computer refers to a computer that can directly issue control commands, usually a PC / host computer / master computer / upper computer, and various signal changes (hydraulic pressure, water level, temperature, etc.) are displayed on the screen.

[0038] Figure 2 Schematic diagram of a fault detection device for a receiving laser of an optical receiving board according to an embodiment of the present invention, comprising:

[0039] Controller 201 and driver impedance 202;

[0040] The controller is used to:

[0041] After the transmitting laser emits an optical signal, the impedance value change command continuously sent by the host computer at preset time intervals is received; each time the driving impedance value change command is received, the impedance value of the driving impedance is changed once, so that the optical power of the transmitting laser is gradually reduced, and the driving impedance is used to drive the light receiving board to work;

[0042] After obtaining the optical receiving board displacement signal fed back by the receiving laser, the signal is fed back to the host computer to trigger the host computer to stop issuing impedance value change commands and use the current impedance value as the impedance threshold; the optical receiving board displacement signal is fed back by the receiving laser after the optical signal cannot be recognized;

[0043] When the impedance threshold is less than a preset minimum impedance threshold, it is determined that the receiving laser fails.

[0044] This solution adopts the mode of optical power scanning. Figure 3 FIG. 1 is a light circuit connection diagram of the light receiving board in an embodiment of the present invention, Figure 3 As shown: the left side is the transmitting laser T, and the right side is the receiving laser R. An optical connection channel is established between the two through a single-mode or multi-mode optical fiber jumper. When used, the driving impedance Z of the transmitting laser T is continuously adjusted to change the driving current Id flowing through the transmitting laser T to change its luminous power P. Figure 4Schematic diagram of the optical power of the transmitting laser, the impedance value of the driving impedance and the turning threshold in the embodiment of the present invention. When the optical power P received by the receiving laser R decreases continuously until it reaches a certain threshold value Pt, it will no longer have the ability to identify the optical signal, and at the same time, there will be an optical receiving board displacement signal S on the receiving board. The threshold value Pt is called the turning threshold value of the receiving laser R, denoted as P t-R At this time, the corresponding driving impedance Z is called the turning impedance, denoted by Z t-R Obviously, for every P t-R , with the corresponding Z t-R Corresponding to (Z t-R The larger the value, the smaller the ID, and P t-R Therefore, when the transmitting laser T is kept unique, for different receiving lasers R, it is only necessary to measure the corresponding turning threshold P t-R You can filter by making a horizontal comparison. Figure 5 FIG. 5 is a schematic diagram of the transverse comparison of the turning impedance of different receiving lasers in the embodiment of the present invention. It can be seen that the receiving laser No. 5 is obviously abnormal. Obviously, for the receiving laser R with obvious abnormality, its turning threshold P t-R It must be higher than the normal receiving laser transition threshold, and the corresponding transition impedance Z t-R It must be lower than the normal receiving laser transition threshold (generally, the transition impedance Z is measured). t-R More direct and convenient). Based on this, the abnormal or faulty receiving laser can be selected.

[0045] In general, the minimum impedance threshold of each type of receiving laser is associated with its hardware circuit. Once the hardware circuit is determined, its minimum impedance threshold is generally fixed. For the same board and the same receiving laser, its minimum impedance threshold can be obtained by multiple sampling measurements.

[0046] In addition, different minimum impedance thresholds can be used in different scenarios. For scenarios with stricter requirements, the minimum impedance threshold can be set higher, and vice versa. The method of disconnection setting is adopted to adapt to different application scenarios. It can be seen that the setting of the minimum impedance threshold should follow the principle of smaller, safer, and larger, more sensitive. At the same time, it is necessary to adjust and optimize according to the actual situation to ensure the stability and reliability of the device.

[0047] Figure 6 Detailed schematic diagram of a fault detection device for a receiving laser of an optical receiving board in an embodiment of the present invention.

[0048] In one embodiment, the driving impedance is a digital potentiometer.

[0049] In one embodiment, the controller uses FPGA, and the FPGA communicates with the digital potentiometer via SPI.

[0050] In specific implementation, FPGA sends a specific value through SPI to change the impedance of the digital potentiometer, thereby changing the driving current of the transmitting laser T. At the same time, the digital potentiometer uploads its own impedance through SPI.

[0051] In one embodiment, the controller is connected to a host computer via a serial communication port. Figure 6 COM is the serial communication port. The serial communication port is set because the electrical levels do not match when the FPGA communicates with the host computer (usually a PC), so an intermediate conversion interface needs to be added.

[0052] During specific implementation, the host computer can send and monitor the size of the driving impedance Z in real time.

[0053] When working, the transmitting laser emits a light signal which is transmitted through the optical fiber to the light receiving board to be detected.

[0054] In one embodiment, the device further comprises a first indicator light and a second indicator light;

[0055] The controller is also used to control the first indicator light to light up when the receiving laser fails, and to control the second indicator light to light up when the receiving laser is normal.

[0056] In one embodiment, the device further comprises a driving MOS tube and a light emitting tube;

[0057] The controller is specifically used to: generate a MOS tube driving signal according to a driving impedance value change command;

[0058] The driving MOS tube is used to drive the light emitting tube after receiving the MOS tube driving signal, wherein when the driving impedance changes, the driving current of the light emitting tube changes, and the driving current is used to drive the emitting laser.

[0059] In one embodiment, the optical power of the transmitting laser is reduced to the turning threshold P t-R When , the receiving laser cannot recognize the optical signal;

[0060] The controller is also used to:

[0061] Record the turning thresholds of multiple receiving lasers of the same type and model of the same type of optical receiving card, wherein when the optical power of the transmitting laser is reduced to the turning threshold, the receiving laser cannot recognize the optical signal;

[0062] According to the maximum turning threshold value and the minimum turning threshold value among the multiple turning threshold values, a threshold range model of the transmitting laser of the same type and model of the same type of optical receiving card is established, wherein the threshold range model is used to determine the allowable range of the turning threshold value of the transmitting laser of the same type and model of the same type of optical receiving card;

[0063] Determine whether the conversion threshold of the actual transmitting laser is within the threshold range model of the corresponding model of the corresponding type of light receiving board;

[0064] If so, it is determined that the optical receiving board is normal; otherwise, it is determined that the optical receiving board is faulty.

[0065] When working, the transmitting laser emits a light signal which is transmitted to the optical receiving board to be detected through the optical fiber. The host computer continuously sends commands to change the impedance of the digital potentiometer, thereby changing the optical power of the transmitting laser. When the optical power P decreases to the turning threshold P t-R When the receiving laser fails to recognize the optical signal, it triggers the optical receiving board displacement signal S. The optical receiving board displacement signal S is fed back to the controller, triggering the host computer to stop issuing commands and save the current impedance value, which is the impedance threshold Z. t-R The controller can also set the minimum impedance threshold Z according to engineering experience. t-R (min), when the detected impedance threshold Z t-R >Z t-R (min), the corresponding receiving laser is normal, the second indicator light is on (green light can be used), indicating normal; when the impedance threshold Z t-R <Z t-R (min), the corresponding receiving laser is abnormal, and the first indicator light is on (red light can be used), indicating abnormality. Figure 7 FIG. 1 is a schematic diagram of an optical signal in an abnormal state in an embodiment of the present invention. In the abnormal state, the optical signal waveform of the receiving laser is distorted or even disappears. Figure 8 2 is a threshold impedance relationship diagram in an embodiment of the present invention. It can be seen that the minimum impedance threshold is the key to determining the impedance threshold.

[0066] The embodiment of the present invention further provides a fault detection system for a receiving laser of an optical receiving board, comprising: a host computer, the aforementioned device;

[0067] The host computer is used to continuously send impedance value change commands after the transmitting laser sends out an optical signal.

[0068] See also Fig. 9 Flow chart of a method for detecting a fault of a receiving laser of an optical receiving board in an embodiment of the present invention. The method for detecting a fault of a receiving laser of an optical receiving board is applied to the aforementioned controller, and includes:

[0069] Step 901, after the transmitting laser emits an optical signal, receiving an impedance value change command continuously sent by the host computer at preset time intervals; each time after receiving the driving impedance value change command, changing the impedance value of the driving impedance once, so that the optical power of the transmitting laser is gradually reduced, and the driving impedance is used to drive the light receiving board to work;

[0070] Step 902, after obtaining the optical receiving board displacement signal fed back by the receiving laser, the signal is fed back to the host computer to trigger the host computer to stop issuing impedance value change commands and use the current impedance value as the impedance threshold; the optical receiving board displacement signal is fed back by the receiving laser after the receiving laser fails to recognize the optical signal;

[0071] Step 903: When the impedance threshold is less than the preset minimum impedance threshold, it is determined that the receiving laser is faulty.

[0072] In the embodiment of the present invention, the controller controls the driving impedance of the laser transmitter continuously at preset time intervals, which equivalently realizes the continuous and smooth change of the optical power of the laser transmitter. After obtaining the optical receiving board displacement signal fed back by the receiving laser, it is fed back to the host computer. The optical receiving board displacement signal can trigger the host computer to stop issuing impedance value change commands, and obtain the current impedance value as the impedance threshold, which can be compared with the minimum impedance threshold to determine whether the receiving laser is faulty. The early screening of the receiving laser of the optical receiving board is realized, so as to intervene in the faulty receiving laser in advance to avoid operation with hidden dangers.

[0073] An embodiment of the present invention further provides a computer device, Fig.10 It is a schematic diagram of a computer device in an embodiment of the present invention. The computer device 1000 includes a memory 1010, a processor 1020, and a computer program 1030 stored in the memory 1010 and executable on the processor 1020. When the processor 1020 executes the computer program 1030, the fault detection method of the receiving laser of the above-mentioned optical receiving board is implemented.

[0074] 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 fault detection method of the receiving laser of the optical receiving board is implemented.

[0075] 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 fault detection method of the receiving laser of the optical receiving board is implemented.

[0076] It will be appreciated by those skilled in the art 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. Furthermore, 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.

[0077] 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 generate 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.

[0078] 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 including 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.

[0079] 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 in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0080] 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 fault detection device for a receiving laser of a light receiving board, characterized in that: Includes: controller and driving impedance; The controller is used to: After the transmitting laser emits an optical signal, the impedance value change command continuously sent by the host computer at preset time intervals is received; each time the driving impedance value change command is received, the impedance value of the driving impedance is changed once, so that the optical power of the transmitting laser is gradually reduced, and the driving impedance is used to drive the light receiving board to work; After obtaining the position change signal of the optical receiving board fed back by the receiving laser, the signal is fed back to the host computer to trigger the host computer to stop sending the impedance value change command and use the current impedance value as the impedance threshold; The optical receiving plate displacement signal is fed back by the receiving laser after failing to identify the optical signal; When the impedance threshold is less than a preset minimum impedance threshold, determining that the receiving laser is faulty; The controller is also used to: Record the turning thresholds of multiple receiving lasers of the same type and model of the same type of optical receiving card, wherein when the optical power of the transmitting laser is reduced to the turning threshold, the receiving laser cannot recognize the optical signal; According to the maximum turning threshold value and the minimum turning threshold value among the multiple turning threshold values, a threshold range model of the transmitting laser of the same type and model of the same type of optical receiving card is established, wherein the threshold range model is used to determine the allowable range of the turning threshold value of the transmitting laser of the same type and model of the same type of optical receiving card; Determine whether the conversion threshold of the actual transmitting laser is within the threshold range model of the corresponding model of the corresponding type of light receiving board; If so, it is determined that the optical receiving board is normal; otherwise, it is determined that the optical receiving board is faulty.

2. The device according to claim 1, characterized in that The driving impedance adopts a digital potentiometer.

3. The device according to claim 2, characterized in that The controller adopts FPGA, and the FPGA communicates with the digital potentiometer via SPI.

4. The device according to claim 1, characterized in that The controller is connected to the host computer via a serial communication port.

5. The device according to claim 1, characterized in that Also includes a first indicator light and a second indicator light; The controller is also used to control the first indicator light to light up when the receiving laser fails, and to control the second indicator light to light up when the receiving laser is normal.

6. The device according to claim 1, characterized in that It also includes driving MOS tubes and light emitting tubes; The controller is specifically used to: generate a MOS tube driving signal according to a driving impedance value change command; The driving MOS tube is used to drive the light emitting tube after receiving the MOS tube driving signal, wherein when the driving impedance changes, the driving current of the light emitting tube changes, and the driving current is used to drive the emitting laser.

7. A fault detection system for a receiving laser of a light receiving board, characterized in that: include: A host computer, a device according to any one of claims 1 to 6; The host computer is used to continuously send impedance value change commands after the transmitting laser sends out an optical signal.

8. A method for detecting a fault of a receiving laser of a light receiving board, characterized in that: A controller used in the device according to any one of claims 1 to 6, comprising: After the transmitting laser emits an optical signal, the impedance value change command continuously sent by the host computer at preset time intervals is received; each time the driving impedance value change command is received, the impedance value of the driving impedance is changed once, so that the optical power of the transmitting laser is gradually reduced, and the driving impedance is used to drive the light receiving board to work; After obtaining the optical receiving board displacement signal fed back by the receiving laser, the signal is fed back to the host computer to trigger the host computer to stop issuing impedance value change commands and use the current impedance value as the impedance threshold; the optical receiving board displacement signal is fed back by the receiving laser after the optical signal cannot be recognized; When the impedance threshold is less than a preset minimum impedance threshold, it is determined that the receiving laser fails.

9. 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 of claim 8 is implemented.

10. 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 of claim 8 is implemented.

11. 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 of claim 8 is implemented.

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