Torque control method and apparatus for drive motor during shift

Abstract

The invention relates to a torque control method of a drive motor during a shift. The method comprises the steps that in the torque reduction stage of the gear shifting period, multiple torque reduction instructions are sent to a driving motor controller, the multiple torque reduction instructions have different torque reduction step lengths, the torque reduction slope is gradually increased in the initial time period of the torque reduction stage, and the torque reduction slope is gradually reduced in the end time period of the torque reduction stage.

Description

Technical Field

[0001] The present application relates to vehicle shift control, and in particular to a method and apparatus for controlling the torque of a drive motor during vehicle shift, a computer storage medium, a computer program product, and a transmission controller. Background Art

[0002] For clutchless electric vehicle transmissions, the transmission cannot use the clutch to unload and load the torque of the drive motor during gear shifting, so the motor needs to be controlled separately to achieve torque coordination.

[0003] Automatic mechanical transmission (AMT) is widely used in commercial electric vehicles. The gear shifting of this type of transmission usually includes torque reduction, gear shifting, speed regulation, gear shifting and torque increase stages, among which the control of torque reduction and torque increase will affect the smoothness of vehicle gear shifting and the drivability of the vehicle. Summary of the invention

[0004] The solution provided in this application is intended to reduce the jerking during gear shifting.

[0005] According to a first aspect of the present application, a method for controlling the torque of a drive motor during gear shifting is disclosed, comprising: in a torque reduction phase during gear shifting, sending a plurality of torque reduction instructions to a drive motor controller, the plurality of torque reduction instructions respectively having different torque reduction step sizes, wherein in an initial time period of the torque reduction phase, a torque reduction slope gradually increases, and in an end time period of the torque reduction phase, the torque reduction slope gradually decreases.

[0006] In one or more embodiments of the first aspect of the present application, optionally, in the torque reduction stage, a torque reduction step length scheme is determined according to the current gear.

[0007] In one or more embodiments of the first aspect of the present application, optionally, in the torque reduction stage, the torque reduction step size indicated by the torque reduction instruction of this round is determined by looking up a table at least based on the current torque of the drive motor and the pedal signal.

[0008] In one or more embodiments of the first aspect of the present application, optionally, in the torque increase phase during gear shifting, multiple torque increase instructions are sent to the drive motor controller, and the multiple torque increase instructions respectively have different torque increase steps, wherein in the initial time period of the torque increase phase, the torque increase slope gradually increases, and in the end time period of the torque increase phase, the torque increase slope gradually decreases.

[0009] In one or more embodiments of the first aspect of the present application, optionally, at the starting time point of the torque reduction phase, the absolute value of the torque reduction slope indicated by the torque reduction command sent to the drive motor controller is consistent with the slope of the torque requested by the whole vehicle; optionally, at the end time point of the torque increase phase, the torque increase slope indicated by the torque increase command sent to the drive motor controller is consistent with the slope of the torque requested by the whole vehicle.

[0010] In one or more embodiments of the first aspect of the present application, optionally, in the torque increase stage, a torque increase step length scheme is determined according to the current gear position.

[0011] In one or more embodiments of the first aspect of the present application, optionally, in the torque increase stage, the torque increase step size indicated by the torque increase instruction of the current round is determined by looking up a table at least based on the current torque of the drive motor and the pedal signal.

[0012] According to a second aspect of the present application, a transmission controller is disclosed, which includes a processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, the processor is capable of executing one or more steps of the method described in the first aspect of the present application.

[0013] According to a third aspect of the present application, a computer program product is disclosed, which includes computer program instructions, wherein when the computer program instructions are executed by a processor, the processor is enabled to perform one or more steps of the method described in the first aspect of the present application.

[0014] According to a fourth aspect of the present application, a computer-readable storage medium is disclosed, wherein instructions are stored in the computer-readable storage medium. When the instructions are executed by a processor, the processor is enabled to execute one or more steps of the method described in the first aspect of the present application.

[0015] According to a fifth aspect of the present application, a torque control device for a drive motor during gear shifting is disclosed, the device comprising: a first module, for sending a plurality of torque reduction instructions to a drive motor controller during a torque reduction phase during gear shifting, the plurality of torque reduction instructions respectively having different torque reduction step sizes, wherein in an initial time period of the torque reduction phase, a torque reduction slope gradually increases, and in an end time period of the torque reduction phase, a torque reduction slope gradually decreases.

[0016] In one or more embodiments of the fifth aspect of the present application, optionally, the device includes a second module for determining a torque reduction step length scheme according to the current gear position during the torque reduction stage.

[0017] In one or more embodiments of the fifth aspect of the present application, optionally, the second module determines the torque reduction step size indicated by the torque reduction instruction of this round according to at least the current torque of the drive motor and the pedal signal in the torque reduction stage.

[0018] In one or more embodiments of the fifth aspect of the present application, optionally, the device includes a third module, which is used to send multiple torque increase instructions to the drive motor controller during the torque increase phase during gear shifting, and the multiple torque increase instructions have different torque increase steps, wherein in the initial time period of the torque increase phase, the torque increase slope gradually increases, and in the end time period of the torque increase phase, the torque increase slope gradually decreases.

[0019] In one or more embodiments of the fifth aspect of the present application, optionally, at the end time point of the torque increase phase, the torque increase slope indicated by the torque increase instruction sent by the third module to the drive motor controller is consistent with the slope of the torque requested by the vehicle.

[0020] In one or more embodiments of the fifth aspect of the present application, optionally, the device includes a fourth module for determining a torque increase step length scheme according to the current gear position during the torque increase stage.

[0021] In one or more embodiments of the fifth aspect of the present application, optionally, the fourth module determines the torque increase step size indicated by the torque increase instruction of the current round according to at least the current torque of the drive motor and the pedal signal in the torque increase stage.

[0022] The inventor of the present application has noticed the problems caused by the torque regulation method during gear shifting in the prior art, and reduces gear shifting shock by using motor torque output with a variable slope, which helps to improve the drivability of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The principles, features and advantages of the present invention will be more fully understood by referring to the following detailed description of specific exemplary embodiments in conjunction with the accompanying drawings.

[0024] Figure 1 is a block diagram of a vehicle shift control system according to an embodiment of the present application.

[0025] Figure 2 It is a schematic diagram of a vehicle shift control process according to an embodiment of the present application.

[0026] Figure 3A It is a schematic diagram of torque control of a drive motor during gear shifting in the prior art.

[0027] Figure 3B Schematic diagram of torque control of a drive motor during gear shifting according to an embodiment of the present application.

[0028] Figure 4 is a torque control flow chart executed by a transmission controller according to one embodiment of the present application.

[0029] Figure 5 is a block diagram of a transmission controller according to an embodiment of the present application. DETAILED DESCRIPTION

[0030] In order to make the technical problems, technical solutions and beneficial technical effects to be solved by the present invention clearer, the present invention will be further described in detail in conjunction with the accompanying drawings and multiple exemplary embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the scope of protection of the present invention. Those skilled in the art will easily recognize that the same principles can be applied to other systems different from the vehicle shift control system described herein, and these same or similar principles can be implemented therein, and any such changes do not deviate from the spirit and scope of the present invention.

[0031] Figure 1 FIG. 1 is a block diagram of a vehicle shift control system according to an embodiment of the present application. Figure 1 As shown, the shift control system 10, i.e., the transmission system 10, includes a transmission controller 11 (TCU, Transmission Control Unit) and a shift actuator 12. The transmission controller 11 is electrically connected to the shift actuator 12. The transmission controller 11 can control the shift actuator 12 to switch gears according to, for example, a vehicle speed signal, an accelerator pedal signal, etc., and a shift strategy stored in the transmission controller 11. The shift actuator 12 can be, for example, an electronically controlled electric shift mechanism. The transmission controller 11 can control the start and stop and speed of the shift motor of the shift actuator 12 through a shift motor driver (not shown in the figure). The rotation of the output of the shift motor is converted into an axial movement of the shift fork in the direction of the input shaft of the transmission system through a transmission component. The axial movement of the shift fork pushes the shift gear sleeve or synchronizer to engage or disengage the shift gear with the transmission gear, thereby achieving gear engagement or disengagement.

[0032] The transmission controller 11 and the vehicle control unit 20 (VCU) can be communicatively coupled via a CAN bus. The vehicle control unit 20 can send signals such as vehicle request torque, vehicle speed signal, and accelerator pedal signal to the transmission controller 11. The transmission controller 11 can send signals such as gear information and drive motor torque to the vehicle control unit 20.

[0033] The transmission controller 11 and the drive motor controller 31 (MCU, Motor Contorl Unit) can be communicatively coupled via a CAN bus. The transmission controller 11 can send instructions such as the motor operation mode, target motor speed, and target motor torque to the drive motor controller 31, and the drive motor controller 31 can send information such as the current motor operation mode, current motor speed, and current motor torque to the transmission controller 11. The drive motor controller 31 is electrically connected to the motor 32 to control the operation of the motor 32. The motor 32 can be a permanent magnet synchronous motor. The motor 32 is mechanically coupled to the gears in the gearbox, so that the output torque of the motor 32 is transmitted to the wheel end of the vehicle through the gear set.

[0034] Figure 2 It is a schematic diagram of a vehicle shift control process according to an embodiment of the present application. Figure 2 The various stages 201 to 205 during the gear shift are schematically shown. In this embodiment, an electrically driven multi-speed gearbox is taken as an example to briefly describe the gear shift process.

[0035] The gear shifting period includes a torque reduction phase 201 , a gear disengagement phase 202 , a speed regulation phase 203 , a gear engagement phase 204 and a torque increase phase 205 .

[0036] In one example, the transmission controller determines whether to trigger a gear shift operation based on signals such as an accelerator pedal signal and a vehicle speed signal, as well as a gear shift strategy stored in the transmission controller.

[0037] It can be understood by those skilled in the art that the judgment of whether to trigger the shift operation can also be performed by the vehicle controller. For example, the vehicle controller can judge whether to trigger the shift operation according to the shift strategy stored in the vehicle controller based on the accelerator pedal signal, brake pedal signal, vehicle speed signal and other vehicle status information and environmental information. When the vehicle controller determines that a shift is required, it calculates the target motor torque, target motor speed and motor operation mode of the drive motor, and determines the target gear and shift instruction flag. The target motor torque, target motor speed, motor operation mode, target gear and shift instruction flag are sent to the drive motor controller and / or the transmission controller via the CAN bus. The drive motor controller receives the target motor torque, target motor speed and motor operation mode from the CAN bus, controls the output torque of the drive motor according to the target motor torque in the torque mode, and controls the output speed of the drive motor according to the target motor speed in the speed mode. The transmission controller receives the target gear and shift instruction flag on the CAN bus, and controls the shift actuator to perform the gear shifting and gear shifting operations.

[0038] In this example, before the shift begins, the drive motor controller receives the vehicle request torque from the vehicle controller to adjust the motor torque; when the transmission controller triggers the shift, the drive motor controller receives the torque request from the transmission controller and enters the shift period. In another example, the transmission controller may not directly enter the shift period according to the shift condition, but first send a shift request to the vehicle controller, and enter the shift period in response to the shift permission instruction from the vehicle controller.

[0039] Back to Figure 2 The schematic diagram of the vehicle shift control process is shown.

[0040] In the torque reduction phase 201, the transmission controller sends a torque reduction command to the drive motor controller to reduce the output torque of the drive motor to the target torque. Since there is no clutch, the torque reduction cannot be completed by mechanical separation. In this phase, the transmission controller controls the motor to operate in a torque mode. The target torque (e.g., zero torque) in this phase makes the meshed gear close to the unloaded synchronous state, so as to prepare for the next gear shift.

[0041] In the gear disengagement phase 202, the transmission controller controls the shift fork to move axially in the direction of the input shaft of the transmission system and pushes the shift sleeve to separate from the transmission gear. Specifically, when the transmission controller receives a torque reduction end signal from the drive motor controller, it controls the shift motor in the shift actuator to make the shift fork reach the neutral position.

[0042] In the speed regulation stage 203, the transmission controller sends a target speed signal to the drive motor controller. In this stage, the transmission controller controls the motor to operate in a speed mode. The drive motor controller regulates the motor speed according to the target speed signal, and controls the speed difference between the synchronizing side and the synchronized side within a predetermined range to reduce the impact of shifting gears.

[0043] In the gear engagement phase 204, the transmission controller controls the shift fork again to push the shift gear sleeve to mesh with the transmission gear. In this phase, the transmission controller controls the motor to re-enter the torque mode. Specifically, when the transmission controller receives the speed regulation end signal from the drive motor controller, it controls the shift gear to mesh with the transmission gear of the target gear.

[0044] In the torque increase phase 205, the transmission controller sends a torque increase command to the drive motor controller to increase the output torque of the drive motor to a target torque. The target torque can be determined by the vehicle controller according to the current accelerator pedal signal, vehicle speed signal and other information.

[0045] Figure 3A Schematic diagram of torque control of a drive motor during gear shifting in the prior art. Figure 2The gear shifting process includes the stages of torque reduction, gear shifting, speed regulation, gear shifting and torque increase. Figure 3A The separation formed by the vertical dotted lines shows the torque reduction stage T1 and the torque increase stage T2, wherein the solid line in the figure shows the change of the drive motor torque over time, and the dotted line in the figure shows the change of the vehicle request torque over time.

[0046] In the existing solution, during the T1 period of torque reduction from point A to point B, the drive motor controller receives a torque reduction command, for example, from a transmission controller, and the output torque of the drive motor is reduced to the target torque at point B. The target torque may be zero torque, or a torque value near zero torque. It can be seen that the torque from point A to point B decreases according to a fixed slope, that is, the torque reduction command received by the drive motor controller each time (for example, once every 10ms) has the same torque reduction step length. Figure 3A The fixed torque slope requested by the transmission controller in the torque reduction phase T1 is different from the vehicle request torque slope generated by the vehicle controller at point A, so the vehicle will jerk at the beginning of the torque reduction phase. At point B, the fixed torque slope requested by the transmission controller in the torque reduction phase T1 immediately becomes zero, so the vehicle will also jerk again at point B.

[0047] To cope with this situation, an embodiment of the present invention eliminates the setbacks generated in the motor torque control stage during the gear shifting process by optimizing the control of the motor torque in the torque reduction stage, thereby reducing the setbacks in the entire gear shifting process. In this embodiment, during the torque reduction stage during the gear shifting, multiple torque reduction instructions are sent to the drive motor controller, and the multiple torque reduction instructions have different torque reduction steps, wherein the torque reduction slope gradually increases in the initial time period of the torque reduction stage, and the torque reduction slope gradually decreases in the end time period of the torque reduction stage. The sum of the initial time period and the end time period is less than or equal to the duration of the torque reduction stage.

[0048] like Figure 3B As shown, in Figure 3A In the corresponding torque reduction stage, a torque reduction curve with a variable slope is generated to eliminate the setbacks generated in the motor torque control stage during the gear shift process, thereby reducing the setbacks during the entire gear shift process. Figure 3B In the torque reduction time period from point A to point B, the drive motor controller receives a torque reduction command from a transmission controller, for example, and the torque from point A to point B decreases according to the changing slope, that is, the multiple torque reduction commands received by the drive motor controller have different torque reduction steps.

[0049] In one example, Figure 3BThe time period of torque reduction from point A to point B can be divided into an initial time period T11, an intermediate time period T12, and an end time period T13 of the torque reduction stage. In the initial time period T11 of the torque reduction stage, the torque reduction slope gradually increases. In the intermediate time period T12, the torque can be reduced with a larger slope. In the end time period T13, the torque reduction slope gradually decreases. Among them, in the initial time period T11 of the torque reduction stage, the torque reduction step is gradually increased, and at the beginning of the time period T11, the absolute value of the torque slope can be equal to or close to the slope of the requested torque of the whole vehicle. In the end time period T13, the torque reduction slope gradually decreases to zero. Those skilled in the art can understand that the torque reduction step of the vehicle under different working conditions can be determined by calibration.

[0050] As described above, in the existing solution, during the T1 period of torque reduction from point A to point B, the torque from point A to point B decreases according to a fixed slope, that is, the torque reduction command received by the drive motor controller each time (for example, once every 10ms) has the same torque reduction step. Figure 3A In the torque rise phase T2, the torque from point C to point D rises according to a fixed slope, that is, the torque rise command received by the drive motor controller each time (for example, once every 10ms) has the same torque rise step. The fixed torque slope requested by the transmission controller is different from the vehicle request torque generated by the vehicle controller at point D, so the vehicle will experience a jerk in the final stage of the torque rise. At point C, the torque slope requested by the transmission controller in the torque rise phase T2 immediately changes from zero to a fixed slope, so the vehicle will also experience another jerk at point C.

[0051] To cope with this situation, an embodiment of the present invention eliminates the setbacks generated in the motor torque control stage during the gear shifting process by optimizing the control of the motor torque in the torque rise stage, thereby reducing the setbacks in the entire gear shifting process. In this embodiment, during the torque rise stage during the gear shifting, multiple torque rise instructions are sent to the drive motor controller, and the multiple torque rise instructions have different torque rise step sizes, wherein the torque rise slope gradually increases in the initial time period of the torque rise stage, and the torque rise slope gradually decreases in the end time period of the torque rise stage. The sum of the initial time period and the end time period is less than or equal to the duration of the torque rise stage.

[0052] like Figure 3B As shown, in Figure 3A In the corresponding torque rise phase, a torque rise curve with a variable slope is generated to eliminate the setbacks generated in the motor torque control phase during the gear shift process, thereby reducing the setbacks during the entire gear shift process. Figure 3BIn the torque reduction time period from point C to point D, the drive motor controller receives a torque increase command from a transmission controller, for example, and the torque from point C to point D increases according to the changing slope, that is, the multiple torque increase commands received by the drive motor controller have different torque increase steps.

[0053] In one example, Figure 3B The time period T2 of the torque increase from point C to point D can be divided into an initial time period, an intermediate time period, and an end time period of the torque increase stage. In the initial time period of the torque increase stage, the torque increase slope gradually increases. In the intermediate time period, the torque can be increased with a larger slope. In the end time period, the torque increase slope gradually decreases. Among them, in the end time period of the torque increase stage, the torque increase step size is gradually increased, and at the end of this time period, the absolute value of the torque slope can be equal to or close to the slope of the torque requested by the whole vehicle. Those skilled in the art can understand that the torque increase step size of the vehicle under different working conditions can be determined by calibration.

[0054] In the above example, by changing the slope of the motor torque, the jerking caused by the change of the motor torque in the torque reduction and torque increase stages during gear shifting can be avoided, the torsional vibration of the transmission system can be reduced, and the drivability of the vehicle can be improved. At the same time, the vehicle's dynamics can be maintained by controlling the slope of the motor torque (for example, a larger torque slope in the middle time period of each of the torque reduction stage and the torque increase stage).

[0055] Figure 4 is a torque control flow chart executed by a transmission controller according to one embodiment of the present application. The transmission controller may be as follows Figure 1 The transmission controller 11 is described.

[0056] Figure 4 The steps in are applicable to torque control in the torque reduction and torque increase stages during gear shifting. Taking the torque control in the torque reduction stage during gear shifting as an example, in step 410, a torque reduction step length scheme is determined according to the current gear. A corresponding torque reduction step length adjustment scheme can be set for each gear. The torque reduction step length scheme is used to determine the torque slope. In step 420, the torque reduction step length indicated by the current round torque reduction instruction is determined by at least looking up the table according to the current torque of the drive motor and the pedal signal. In a specific example, the current round torque reduction step length can be determined by the ratio of the current motor torque to the previous round motor torque, combined with the pedal signal table lookup. It can be understood by those skilled in the art that the lookup table can be obtained by calibration. In step 430, the current round torque reduction instruction is sent to the motor driver. Thereby, the sending of a torque reduction instruction is completed. This embodiment of the present application can avoid gear shift setbacks caused by unreasonable changes in slope by dynamically adjusting the torque of each torque reduction instruction to have a different step length from the previous one during a period of time.

[0057] Figure 4The process of torque control performed by the transmission controller can be implemented by one or more software functional units in the transmission controller. The division of functional units is a logical function division, and there may be other division methods when implementing it. Multiple units and devices can be physically separated or distributed on network units, which can be combined or integrated into another system.

[0058] Figure 2 and 4 Each step of the flowchart in the figure 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 or other programmable data processing device to form a machine, so as to execute these instructions by the processor of the computer or other programmable data processing device. In some alternative implementations, the steps shown in the box may not occur in the order shown in the flowchart. For example, the two boxes shown in sequence can actually be executed substantially simultaneously or in different orders.

[0059] Figure 5 FIG. 5 is a block diagram of a transmission controller according to an embodiment of the present application. The vehicle transmission controller 500 is used to implement, for example, Figure 1 The control operation of the transmission controller 11 in the embodiment of the present invention is applied to Figure 2 and 4 The control method shown. The transmission controller 500 may include a processor 510 and a memory 520. The processor 510 and the memory 520 communicate via a bus, or may communicate via other means such as wireless transmission. The memory 520 is used to store instructions, and the processor 510 is used to execute the instructions stored in the memory 520. The memory 520 may include a read-only memory (ROM) and a random access memory (RAM). The processor 510 may call the program code stored in the memory 520 to execute multiple steps of the method described above. The transmission controller 500 also includes Figure 5 The transmission controller 500 communicates with various vehicle electronic components via an input / output (I / O) interface. The computer program code stored in the memory 520 is loaded into the memory and then executed by the processor 510.

[0060] One or more of the above embodiments, one or more examples, can be implemented in whole or in part by software, hardware or a combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes computer program instructions, which can be downloaded to the memory of the controller via a computer network, or can be transmitted to the memory of the controller in a wired manner. When the computer program instructions are executed by the processor of the controller, the processor is enabled to perform one or more steps of the method described herein. The computer program instructions can be provided in a computer-readable storage medium. The computer-readable storage medium referred to herein can be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0061] The above description is only a specific embodiment of the present application, and the protection scope of the present application is not limited thereto. Those skilled in the art can think of other feasible changes or substitutions based on the technical content and teachings disclosed in the present application, and such changes or substitutions are all included in the protection scope of the present application. Where appropriate, the embodiments of the present application and the features of the embodiments may be combined with each other. The protection scope of the present application shall be subject to the description of the claims.

Claims

1. A method for controlling the torque of a drive motor during gear shifting, characterized in that: include: During the torque reduction phase of the gear shift, multiple torque reduction instructions are sent to the drive motor controller, wherein the multiple torque reduction instructions have different torque reduction step sizes. In the initial time period of the torque reduction phase, the torque reduction slope gradually increases, and in the end time period of the torque reduction phase, the torque reduction slope gradually decreases.

2. The method according to claim 1, characterized in that: In the torque reduction stage, a torque reduction step length scheme is determined according to the current gear position.

3. The method according to claim 2, characterized in that: In the torque reduction stage, the torque reduction step length indicated by the torque reduction instruction of the current round is determined by looking up a table at least according to the current torque of the drive motor and the pedal signal.

4. The method according to claim 1, characterized in that: During the torque increase phase during the gear shift, multiple torque increase instructions are sent to the drive motor controller, wherein the multiple torque increase instructions have different torque increase step lengths. In the initial time period of the torque-raising stage, the torque-raising slope gradually increases, and in the end time period of the torque-raising stage, the torque-raising slope gradually decreases.

5. The method according to claim 1, characterized in that: At the start time point of the torque reduction phase, the absolute value of the torque reduction slope indicated by the torque reduction instruction sent to the drive motor controller is consistent with the slope of the vehicle requested torque, and, At the end time point of the torque increase phase, the torque increase slope indicated by the torque increase instruction sent to the drive motor controller is consistent with the slope of the vehicle requested torque.

6. The method according to claim 4, characterized in that: In the torque increase stage, a torque increase step length scheme is determined according to the current gear position.

7. The method according to claim 4, characterized in that: In the torque increase stage, the torque increase step length indicated by the torque increase instruction of the current round is determined by looking up a table at least according to the current torque of the drive motor and the pedal signal.

8. A transmission controller, characterized in that: The controller comprises a processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, the processor is capable of performing the method according to any one of claims 1-7.

9. A computer program product comprising computer program instructions, wherein: When the computer program instructions are executed by a processor, the processor is enabled to perform the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, wherein instructions are stored in the computer-readable storage medium, characterized in that: When the instructions are executed by a processor, the processor is enabled to perform the method according to any one of claims 1 to 7.

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