Position cascade active-disturbance-rejection control method for permanent magnet synchronous motor

Abstract

The invention relates to a position cascade active-disturbance-rejection control method for a permanent magnet synchronous motor. The invention relates to the technical field of motor control. The method comprises the following steps: establishing a permanent magnet synchronous motor mathematical model considering load torque disturbance and parameter perturbation; a three-order linear expansion state observer and a three-order nonlinear expansion state observer are configured in a cascade mode, disturbance estimation is completed by the linear expansion state observer in the front stage, observation errors are corrected by the nonlinear expansion state observer in the rear stage, and therefore the identification precision of the system on load torque disturbance is improved. Disturbance compensation is realized through linear state error feedback, and a position and speed integrated position cascade active disturbance rejection controller is designed. Compared with an existing single observer architecture, the precise tracking characteristic of the nonlinear extended state observer is reserved, meanwhile, the disturbance adaptation threshold value is widened through the linear extended state observer, the load disturbance resistance of the position servo system is enhanced, and the response speed and robustness of the system are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of motor control, and is a position cascade active disturbance rejection control method for a permanent magnet synchronous motor. Background Art

[0002] The position control accuracy of a permanent magnet synchronous motor is an important technical index to measure the performance of a servo system. In practical applications, the control performance of the servo system is mainly restricted by two factors: one is various disturbances from the outside world, and the other is the inherent characteristics of the motor. Especially in the position control link, nonlinear factors such as load torque disturbance, system friction interference, and measurement error of feedback components will significantly affect the control performance of the system, resulting in a decline in the dynamic response characteristics of the system and an increase in the steady-state error.

[0003] To address these technical challenges, active disturbance rejection control, as an advanced nonlinear control method, has been widely used in the field of servo control. Its core advantage lies in being able to effectively handle the nonlinear characteristics and uncertainties in the system, and significantly improving the robustness and dynamic performance index of the system. The active disturbance rejection controller adopts a modular design and is mainly composed of three functional modules: a transition link, a state error feedback control law, and an extended state observer (ESO). Among them, the extended state observer can quickly respond to the position command and effectively suppress the load disturbance by estimating the system state and external disturbances in real time and combining the state error feedback control law, so as to achieve high-precision position tracking.

[0004] The extended state observer can be divided into two types: linear and nonlinear according to its algorithm characteristics. Research shows that the nonlinear extended state observer exhibits superior steady-state tracking accuracy and disturbance rejection performance under small disturbance conditions, but its disturbance rejection ability will significantly decay as the disturbance amplitude increases. In contrast, the linear extended state observer has stronger adaptability to changes in the disturbance amplitude, and its performance is basically not affected by changes in the disturbance amplitude. This characteristic makes the two observers have their own advantages and disadvantages in practical applications. For example, the linear extended state observer has a poor response speed to disturbances, while the disturbance rejection ability of the nonlinear extended state observer rapidly decays as the disturbance amplitude increases, which limits the application range of the position servo system based on active disturbance rejection. Summary of the Invention

[0005] In view of the characteristics and problems of the extended state observer in active disturbance rejection, the present invention designs a cascade linear-nonlinear extended state observer to improve the estimation accuracy of the system for large disturbances, and ensures that the position servo system of the permanent magnet synchronous motor based on active disturbance rejection has good anti-disturbance ability in a large range. The present invention provides a position cascade active disturbance rejection control method for a permanent magnet synchronous motor.

[0006] The present invention provides the following technical solutions:

[0007] A position cascaded active disturbance rejection control method for a permanent magnet synchronous motor, the method comprising the following steps:

[0008] Step 1: Establish a mathematical model of the permanent magnet synchronous motor considering load torque disturbance and parameter perturbation;

[0009] Step 2: Cascade-configure a third-order linear extended state observer and a third-order nonlinear extended state observer. The front stage completes disturbance estimation by the linear extended state observer, and the rear stage corrects the observation error through the nonlinear extended state observer;

[0010] Step 3: Achieve disturbance compensation through linear state error feedback, design a third-order active disturbance rejection controller for position and speed integration, and complete active disturbance rejection control.

[0011] Preferably, the specific content of Step 1 is:

[0012] Establish a voltage equation for the total current loop interference:

[0013]

[0014] where, u d and u q are the stator voltages of the d-axis and q-axis; R s is the stator resistance; ω e is the electrical angular velocity of the rotor; ψ f is the magnetic flux; L d and L q are the stator inductances of the d-axis and q-axis, f id and f iq respectively represent the total current disturbances of the d-axis and q-axis.

[0015] Preferably, Step 1 further includes:

[0016] Establish a motion equation for the total disturbance of the disturbance torque in the position loop caused by cogging torque, mechanical parameter perturbation, friction torque, current sampling error, and unmodeled dynamics as:

[0017]

[0018] Preferably, the specific content of Step 2 is:

[0019] The front-stage linear extended state observer is represented by the following formula:

[0020]

[0021] The rear-stage is designed as a nonlinear extended state observer and is represented by the following formula:

[0022]

[0023] Preferably, step 3 is specifically as follows:

[0024] The disturbance estimated by the pre-stage linear extended state observer and the disturbance residual estimated by the post-stage non-linear extended state observer are superimposed as the total disturbance estimate of the system for feedforward compensation. At the same time, a linear state error feedback control law is used, which is expressed by the following formula:

[0025]

[0026] Preferably, through cascaded linear-nonlinear active disturbance rejection control, the maximum offset during the action of the disturbance is smaller, the callback time is shorter, and the callback process is smoother.

[0027] Preferably, the disturbances affecting the control accuracy of the permanent magnet synchronous motor servo system include flux harmonics, electrical parameter perturbations, inverter non-linearity, unmodeled electrical disturbances, and current cross-coupling.

[0028] A position cascaded active disturbance rejection control system for a permanent magnet synchronous motor, the system comprising:

[0029] A model establishment module that establishes a mathematical model of a permanent magnet synchronous motor considering load torque disturbance and parameter perturbation;

[0030] A disturbance estimation module that cascades and configures a third-order linear extended state observer and a third-order non-linear extended state observer. The pre-stage completes disturbance estimation by a linear extended state observer, and the post-stage corrects the observation error through a non-linear extended state observer;

[0031] A control module that realizes disturbance compensation through linear state error feedback, designs a third-order active disturbance rejection controller for position and speed integration, and completes active disturbance rejection control.

[0032] A computer-readable storage medium, on which a computer program is stored, and the program is executed by a processor to implement a position cascaded active disturbance rejection control method for a permanent magnet synchronous motor.

[0033] A computer device, comprising a memory and a processor, the memory stores a computer program, and the processor implements a position cascaded active disturbance rejection control method for a permanent magnet synchronous motor when executing the computer program.

[0034] The present invention has the following beneficial effects:

[0035] Compared with the prior art, the present invention:

[0036] The present invention proposes a position cascaded active disturbance rejection control method for permanent magnet synchronous motors. Aiming at the characteristic that the nonlinear extended state observer has excellent steady-state accuracy under small disturbance conditions but its disturbance rejection performance decreases significantly with the increase of disturbance amplitude, it complements the advantage of the linear extended state observer with strong stability in the full disturbance range. This solution proposes a two-stage observer cascaded architecture for position control: the front-stage linear extended state observer realizes the robustness perception of disturbance amplitude, and the rear-stage nonlinear extended state observer dynamically corrects the disturbance observation error to form a collaborative observation mechanism. The implementation steps of this method are as follows: First, establish a mathematical model of the permanent magnet synchronous motor considering load torque disturbance and parameter perturbation; Second, cascade and configure a third-order linear extended state observer and a third-order nonlinear extended state observer. The front stage completes disturbance estimation by the linear extended state observer, and the rear stage corrects the observation error through the nonlinear extended state observer to improve the identification accuracy of the system for load torque disturbance; Third, realize disturbance compensation through linear state error feedback, and design a third-order active disturbance rejection controller for position and speed integration.

[0037] The position control method of the cascaded linear-nonlinear active disturbance rejection permanent magnet synchronous motor has significantly better position response speed and disturbance rejection ability than the traditional PI control. Compared with linear active disturbance rejection and nonlinear active disturbance rejection, the cascaded linear-nonlinear active disturbance rejection has a smaller maximum offset, a shorter callback time, and a smoother callback process when disturbed. When suppressing composite disturbances including periodic disturbances and measurement noise, the disturbance rejection effect is significantly better than that of linear and nonlinear active disturbance rejection. Description of the Drawings

[0038] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0039] Figure 1 It shows the structure diagram of the motor control system using cascaded linear-nonlinear active disturbance rejection of the present invention;

[0040] Figure 2 It shows the position response waveform diagrams of cascaded active disturbance rejection and PI when there is a step response and sudden addition / subtraction of load in the present invention;

[0041] Figure 3 It shows the position response waveform diagrams of three active disturbance rejection methods for suppressing load torque disturbance;

[0042] Figure 4 It shows the speed response waveform diagrams of three active disturbance rejection methods for suppressing load torque disturbance;

[0043] Figure 5 It shows the position response waveform diagrams of three active disturbance rejection methods for suppressing composite disturbances. Specific embodiments

[0044] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0045] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0047] The following is a detailed description of the present invention in conjunction with specific embodiments. Specific Embodiment 1:

[0049] According to Figures 1 to 5 As shown, the specific optimized technical solution adopted by the present invention to solve the above technical problems is: The present invention relates to a position cascade active disturbance rejection control method for a permanent magnet synchronous motor.

[0050] The present invention provides a position cascade active disturbance rejection control method for a permanent magnet synchronous motor, and the method includes the following steps:

[0051] Step 1: Establish a mathematical model of a permanent magnet synchronous motor considering load torque disturbance and parameter perturbation;

[0052] Step 2: Cascade-configure a third-order linear extended state observer and a third-order nonlinear extended state observer. The front stage completes disturbance estimation by the linear extended state observer, and the rear stage corrects the observation error through the nonlinear extended state observer;

[0053] Step 3: Implement disturbance compensation through linear state error feedback, design a third-order active disturbance rejection controller for position and speed integration, and complete the active disturbance rejection control.

[0054] The present invention proposes a position cascade active disturbance rejection control method for permanent magnet synchronous motors. Aiming at the characteristics that the nonlinear extended state observer has excellent steady-state accuracy under small disturbance conditions but its disturbance rejection performance decreases significantly with the increase of disturbance amplitude, it complements the advantage of the linear extended state observer with strong stability in the full disturbance range. This solution proposes a two-stage observer cascade architecture for position control: the front-stage linear extended state observer realizes the robust perception of disturbance amplitude, and the rear-stage nonlinear extended state observer dynamically corrects the disturbance observation error to form a collaborative observation mechanism. The implementation steps of this method are as follows: First, establish a mathematical model of the permanent magnet synchronous motor considering load torque disturbance and parameter perturbation; Second, cascade configure a third-order linear extended state observer and a third-order nonlinear extended state observer. The front stage estimates the disturbance by the linear extended state observer, and the rear stage corrects the observation error through the nonlinear extended state observer to improve the identification accuracy of the system for load torque disturbance; Third, implement disturbance compensation through linear state error feedback, and design a position cascade active disturbance rejection controller for position and speed integration.

[0055] Compared with the existing single-observer architecture, while retaining the precise tracking characteristics of the nonlinear extended state observer, the present invention broadens the disturbance adaptation threshold through the linear extended state observer, enhances the anti-load disturbance ability of the position servo system, and improves the response speed and robustness of the system. Specific Embodiment 2:

[0057] The difference between Embodiment 2 and Embodiment 1 of this application is only that:

[0058] The specific step 1 is:

[0059] Establish the voltage equation of the total current loop interference:

[0060]

[0061] where, u d and u q are the stator voltages of the d-axis and q-axis; R s is the stator resistance; ω e is the electrical angular velocity of the rotor; ψ f is the magnetic flux; L d and L q are the stator inductances of the d-axis and q-axis, and f id and f iq respectively represent the total current disturbances of the d-axis and q-axis. Specific Embodiment 3:

[0063] The difference between the third embodiment and the second embodiment of this application is only that:

[0064] Step 1 further includes:

[0065] For the disturbance torque in the position loop caused by cogging torque, mechanical parameter perturbation, friction torque, current sampling error, and unmodeled dynamics, the motion equation of the total disturbance is established as:

[0066] Specific Embodiment Four:

[0068] The difference between the fourth embodiment and the third embodiment of this application is only that:

[0069] Step 2 is specifically:

[0070] The front-stage linear extended state observer is represented by the following formula:

[0071]

[0072] The rear-stage is designed as a non-linear extended state observer and is represented by the following formula:

[0073] Specific Embodiment Five:

[0075] The difference between the fifth embodiment and the fourth embodiment of this invention is only that:

[0076] Step 3 is specifically:

[0077] The disturbance estimated by the front-stage linear extended state observer and the disturbance residual estimated by the rear-stage non-linear extended state observer are superimposed as the total disturbance estimate of the system for feed-forward compensation. At the same time, a linear state error feedback control law is used, which is represented by the following formula:

[0078] Specific Embodiment Six:

[0080] The difference between the sixth embodiment and the fifth embodiment of this invention is only that:

[0081] Through cascaded linear-nonlinear active disturbance rejection control, the maximum offset during the action of the disturbance is smaller, the callback time is shorter, and the callback process is smoother. Specific Embodiment Seven:

[0083] The difference between the seventh embodiment and the sixth embodiment of this invention is only that:

[0084] The disturbances affecting the control accuracy of the permanent magnet synchronous motor servo system include flux harmonics, electrical parameter perturbation, inverter non-linearity, unmodeled electrical interference, and current cross-coupling. Specific Embodiment VIII:

[0086] The difference between the eighth embodiment and the seventh embodiment of the present invention lies only in that:

[0087] The present invention provides a permanent magnet synchronous motor position cascaded active disturbance rejection control system, and the system includes:

[0088] A model establishment module, which establishes a mathematical model of a permanent magnet synchronous motor considering load torque disturbance and parameter perturbation;

[0089] A disturbance estimation module, which cascades a third-order linear extended state observer and a third-order nonlinear extended state observer. The front stage completes disturbance estimation by the linear extended state observer, and the rear stage corrects the observation error through the nonlinear extended state observer;

[0090] A control module, which realizes disturbance compensation through linear state error feedback, designs a third-order active disturbance rejection controller for position and speed integration, and completes active disturbance rejection control. Specific Embodiment IX:

[0092] The difference between the ninth embodiment and the eighth embodiment of the present invention lies only in that:

[0093] The present invention provides a computer-readable storage medium, on which a computer program is stored, and the program is executed by a processor to implement a permanent magnet synchronous motor position cascaded active disturbance rejection control method. Specific Embodiment X:

[0095] The difference between the tenth embodiment and the ninth embodiment of the present invention lies only in that:

[0096] The present invention provides a computer device, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, a permanent magnet synchronous motor position cascaded active disturbance rejection control method is implemented. Specific Embodiment XI:

[0098] The difference between the eleventh embodiment and the tenth embodiment of the present invention lies only in that:

[0099] The present invention proposes a position cascaded active disturbance rejection control method for a permanent magnet synchronous motor. Aiming at the characteristic that the nonlinear extended state observer has excellent steady-state accuracy under small disturbance conditions but its disturbance rejection performance decreases significantly with the increase of disturbance amplitude, it complements the advantage of the linear extended state observer in having strong stability within the full disturbance range. This solution proposes a two-stage observer cascaded architecture for position control: the front-stage linear extended state observer realizes the robustness perception of the disturbance amplitude, and the rear-stage nonlinear extended state observer dynamically corrects the disturbance observation error to form a collaborative observation mechanism. The implementation steps of this method are as follows: First, establish a mathematical model of the permanent magnet synchronous motor considering load torque disturbance and parameter perturbation; Second, cascade a third-order linear extended state observer and a third-order nonlinear extended state observer. The front stage completes the disturbance estimation by the linear extended state observer, and the rear stage corrects the observation error through the nonlinear extended state observer to improve the system's identification accuracy of the load torque disturbance; Third, realize disturbance compensation through linear state error feedback and design a third-order active disturbance rejection controller integrating position and speed.

[0100] The implementation steps are specifically as follows:

[0101] Figure 1 It is the structure diagram of the motor control system adopting cascaded linear-nonlinear active disturbance rejection. The implementation steps of this method are as follows: First, establish a mathematical model of the permanent magnet synchronous motor considering load torque disturbance and parameter perturbation; Second, cascade a third-order linear extended state observer and a third-order nonlinear extended state observer. The front stage completes the disturbance estimation by the linear extended state observer, and the rear stage corrects the observation error through the nonlinear extended state observer to improve the system's identification accuracy of the load torque disturbance; Third, realize disturbance compensation through linear state error feedback and design a third-order active disturbance rejection controller integrating position and speed.

[0102] The implementation steps are specifically as follows:

[0103] Step 1: Establish a mathematical model of the permanent magnet synchronous motor considering load torque disturbance and parameter perturbation.

[0104] In practical applications, the disturbances affecting the control accuracy of the permanent magnet synchronous motor servo system include flux harmonics, electrical parameter perturbations, inverter nonlinearities, unmodeled electrical disturbances, and current cross-coupling. Therefore, the voltage equation considering the total current loop disturbance is:

[0105]

[0106] where, u d and u q are the stator voltages of the d-axis and q-axis; R s is the stator resistance; ω e is the electrical angular velocity of the rotor; ψ f is the magnetic flux; L d and Lq are the stator inductances of the d-axis and q-axis, f id and f iq respectively represent the total current disturbances of the d-axis and q-axis.

[0107] Similarly, for the disturbance torque in the position loop caused by cogging torque, mechanical parameter disturbances, friction torque, current sampling error, and unmodeled dynamics, the motion equation considering the total disturbance is:

[0108]

[0109] Step 2: Cascade-configure a third-order linear extended state observer and a third-order nonlinear extended state observer. The front stage completes disturbance estimation by the linear extended state observer, and the rear stage corrects the observation error through the nonlinear extended state observer, so as to improve the identification accuracy of the system for load torque disturbance.

[0110] The specific form of the front-stage linear extended state observer is:

[0111]

[0112] The rear stage is designed as a nonlinear extended state observer, and the specific form is:

[0113]

[0114] Step 3: Achieve disturbance compensation through linear state error feedback and design a third-order active disturbance rejection controller for position and speed integration.

[0115] Superimpose the disturbance estimated by the front-stage linear extended state observer and the disturbance residual estimated by the rear-stage nonlinear extended state observer as the total disturbance estimate of the system for feedforward compensation. At the same time, use the linear state error feedback control law, specifically as follows:

[0116]

[0117] Figure 2 is the position response waveform diagram of cascade active disturbance rejection and PI when there is a step response and sudden load addition / subtraction; the simulation shows that the position response speed and disturbance rejection effect of the method based on active disturbance rejection are better than those of traditional PI control.

[0118] Figure 3 is the position response waveform diagram of three active disturbance rejection methods for suppressing load torque disturbance;

[0119] Figure 4 is the speed response waveform diagram of three active disturbance rejection methods for suppressing load torque disturbance;

[0120] Figure 5 is the position response waveform diagram of three active disturbance rejection methods for suppressing composite disturbance;

[0121] It can be seen from the above simulation waveforms that the position response speed and disturbance rejection ability of the cascaded linear-nonlinear active disturbance rejection permanent magnet synchronous motor position control method are significantly better than those of the traditional PI control. Compared with the linear active disturbance rejection and the nonlinear active disturbance rejection, the cascaded linear-nonlinear active disturbance rejection has a smaller maximum offset, a shorter callback time, and a smoother callback process during the disturbance. When suppressing the composite disturbance including periodic disturbance and measurement noise, the disturbance rejection effect is significantly better than that of the linear and nonlinear active disturbance rejection.

[0122] The above is only a preferred implementation mode of a cascaded active disturbance rejection control method for the position of a permanent magnet synchronous motor. The protection scope of a cascaded active disturbance rejection control method for the position of a permanent magnet synchronous motor is not limited to the above embodiments. All technical solutions belonging to this idea fall within the protection scope of the present invention. It should be pointed out that for those skilled in the art, several improvements and changes made without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A permanent magnet synchronous motor position cascade anti-disturbance control method, characterized by: The method comprises the following steps: Step 1: Establish a mathematical model of the permanent magnet synchronous motor considering load torque disturbance and parameter perturbation; Step 2: The third-order linear extended state observer and the third-order nonlinear extended state observer are cascaded, with the linear extended state observer completing disturbance estimation in the front stage and the nonlinear extended state observer correcting the observation error in the back stage; Step 3: Realize disturbance compensation through linear state error feedback, design a third-order active disturbance rejection controller integrating position and speed, and complete active disturbance rejection control.

2. The method according to claim 1, characterized in that: The step 1 is specifically as follows: Establish the voltage equation for the total current loop disturbance: Among them, u d and u q is the stator voltage of the d-axis and q-axis; R s is the stator resistance; ω e is the electrical angular velocity of the rotor; ψ f is the magnetic linkage; L d and L q is the stator inductance of the d-axis and q-axis, f id and f iq They represent the total current disturbances of the d-axis and q-axis respectively.

3. The method according to claim 2, characterized in that: The step 1 also includes: The disturbance torque in the position loop caused by cogging torque, mechanical parameter disturbance, friction torque, current sampling error and unmodeled dynamics establishes the motion equation of the total disturbance as:

4. The method according to claim 3, characterized in that: The step 2 is specifically as follows: The previous linear extended state observer is expressed as follows: The latter stage is designed as a nonlinear extended state observer expressed by the following formula:

5. The method according to claim 4, characterized in that: The step 3 is specifically as follows: The disturbance estimated by the front-stage linear extended state observer and the disturbance residual estimated by the back-stage nonlinear extended state observer are superimposed as the total disturbance estimate of the system, and feedforward compensation is performed. At the same time, the linear state error feedback control law is used, which is expressed by the following formula:

6. The method according to claim 5, characterized in that: Through cascaded linear and nonlinear anti-disturbance control, the maximum offset under disturbance is smaller, the callback time is shorter, and the callback process is smoother.

7. The method according to claim 1, characterized in that: The disturbances that affect the control accuracy of permanent magnet synchronous motor servo systems include flux harmonics, electrical parameter disturbances, inverter nonlinearity, unmodeled electrical disturbances, and current cross-coupling.

8. A permanent magnet synchronous motor position cascade anti-disturbance control system, characterized by: The system comprises: A model building module, wherein the model building module builds a mathematical model of a permanent magnet synchronous motor taking into account load torque disturbance and parameter perturbation; A disturbance estimation module, wherein the disturbance estimation module cascades a third-order linear extended state observer and a third-order nonlinear extended state observer, wherein the linear extended state observer completes disturbance estimation in the front stage and the nonlinear extended state observer corrects observation errors in the rear stage; The control module realizes disturbance compensation through linear state error feedback, designs a third-order active disturbance rejection controller integrating position and speed, and completes active disturbance rejection control.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the method according to claims 1-7.

10. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the method of claims 1-7 is implemented.

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