CN109474222B - Variable load servo system vibration suppression method and system based on notch filter - Google Patents

Abstract

The invention provides a vibration suppression method and system for a variable load servo system based on a notch filter. The method includes: directly starting from the time domain model of the servo system, analyzing the real-time position data returned by the position sensor, and preferentially using The time difference between the last two extreme points when the residual vibration starts to vibrate is used to analyze the center frequency of the vibration, and a notch filter is configured, and then the center frequency is corrected by the time difference between the adjacent maximum points after the vibration. The beneficial effects of the present invention are: the time domain analysis method adopted by the technical solution of the present invention can quickly detect the change of the center frequency, and the center frequency can be obtained in one cycle after the vibration is generated by the load change, the real-time performance is strong, and according to the Real-time correction of filter parameters and center frequency for subsequent vibration conditions can obtain excellent filtering effects. In the case of variable loads, it is a simple and real-time vibration suppression method.

Description

Vibration suppression method and system for variable load servo system based on notch filter

technical field

The invention relates to the technical field of motor control, in particular to a vibration suppression method and system for a variable load servo system based on a notch filter.

Background technique

Servo system is an important part of industrial automation and a necessary way to achieve precise positioning and precise movement in the automation industry. The servo system can make the position, speed, torque and other output parameters of the terminal actuator of the system accurately follow the change of the input quantity.

In recent years, AC servo technology has developed rapidly and has excellent performance, and has gradually become the main super product of servo. However, in practical use, the rapidity and positioning accuracy of the system often cannot be taken into account at the same time. In systems that require high rapidity, the steady-state accuracy of some systems is usually sacrificed, and the system has large overshoot or even chattering. For example, the end manipulator in the servo manipulator system, if the chattering phenomenon is serious, the end manipulator of the manipulator cannot work at all.

The phenomenon of positioning chattering causes the bandwidth of the servo system to be narrowed and the positioning stability to decrease, forcing the designer to reduce the servo gain, resulting in a lower stiffness of the servo system and a longer response time, which affects the trajectory tracking and high-speed positioning of the servo system. performance. The chattering of the positioning end on the high-precision machine tool will seriously affect the surface quality of the workpiece and damage the machine tool. Long-term action will also cause wear and tear of the mechanical coupling device, which will lead to production accidents in severe cases. Therefore, the suppression of servo system positioning jitter is a key common technology in the field of motor drive, which is of great significance for improving the stability of the servo system and improving the dynamic response quality of the system.

There is a control method for motor vibration suppression (CN105375850B) similar to the published patent. The method of the patent is: firstly, the whole process of the motor rotation is sampled, the sampling results are first stored in the buffer, and then the stored sampling results are performed. Lie transform, transfer to the frequency domain, easy to analyze; then based on the average value of the vibration frequency of the motor speed ω ₀ , and analyze the surrounding frequencies at the same time, according to the amplitude of different situations, the design according to the center frequency is in line with the actual engineering The required filter parameters are used to achieve the purpose of suppressing the vibration end. Finally, the amplitude-frequency characteristics after the filter design are analyzed to determine whether the vibration suppression situation meets the actual needs. If it meets the requirements, end the filter configuration; if it does not meet the requirements, analyze the reasons. The most likely reason is that the vibration center frequency is not completely attenuated due to improper filter parameters. At this time, return to resampling and configure the filter.

The existing method is aimed at the situation where the load is unchanged. When the load changes, the vibration center frequency will change, and the filter needs to be reconfigured. However, in the actual process, the filter is configured offline, and the specific configuration process is performed after the vibration. carried out, this method cannot be used under variable load conditions.

The fast Fourier transform technology converts the signal from the time domain to the frequency domain. The result is very intuitive and easy to analyze the frequency. However, the Fourier transform requires a certain amount of basic data to obtain an accurate spectrum. In the actual process, the mechanical The high-speed state transformation of the motor in the arm servo system requires high real-time performance. If you sample and analyze first, and then bring the data of the previous period into the later period of time, due to the real-time change of the load, it is not enough to support the Fourier transform. A sufficient amount of data is required, so the method of designing a notch filter using Fourier transform analysis parameters is not feasible in the case of variable loads.

SUMMARY OF THE INVENTION

In order to solve the above problems, the present invention provides a vibration suppression method and system for a variable load servo system based on a notch filter, and a vibration suppression method for a variable load servo system based on a notch filter, which mainly includes the following steps:

S101: Modeling an elastic connection device of a servo system that needs to suppress vibration to obtain a servo system model; a position sensor for measuring the amplitude of the system is installed in the servo system;

S102: Acquire the amplitude data of the position sensor in the servo system;

S103: Determine whether the system has residual vibration according to the amplitude data? If yes, go to step S104; otherwise, go back to step S102;

S104: Design a notch filter according to the servo system model, and use the designed notch filter to suppress the residual vibration of the servo system; the initial center frequency of the residual vibration of the servo system is ω ₀ , according to the amplitude data calculation;

S105: Use the position sensor to obtain the amplitude data of the servo system after the residual vibration is suppressed; and judge whether there is residual vibration in the current servo system according to the amplitude data of the servo system after the vibration suppression? If yes, go to step S106; otherwise, go back to step S102;

S106: According to the amplitude data of the servo system after the vibration suppression, calculate the first center frequency ω' ₀ of the residual vibration of the servo system after the vibration suppression;

S107: According to the relationship between ω' ₀ and ω ₀ , update the parameters of the notch filter online;

S108: Determine whether the servo system is stopped? If so, go to step S109; otherwise, use the updated notch filter to suppress the residual vibration of the system again, and return to step S107;

S109: End the residual vibration suppression program.

Further, in step S101, the transfer function between the load speeds of the motors of the servo system model is shown in formula (1):

In the above formula, J ₂ is the moment of inertia of the load; θ ₁ is the rotation angle of the motor shaft; θ ₂ is the load rotation angle; K is the torsional elasticity coefficient of the transmission shaft.

Further, in step S103, the method of judging whether the system has residual vibration according to the amplitude data is: obtaining the maximum amplitude Hmax in the amplitude data; whether the judgment condition Hmax≥x is established? If yes, it is determined that there is residual vibration; otherwise, it is determined that there is no residual vibration; wherein, x is greater than 0, which is the vibration threshold, and is a preset value.

Further, in step S104, the transfer function of the designed notch filter is shown in formula (2):

k₁为陷波宽度，k₂为陷波深度，

k₁＝5k₂，ω₀为伺服系统残余振动的初始中心频率，根据所述振幅数据计算获得；ω₁和ω₂分别为陷波滤波器的起始抑制频率和终止抑制频率，ω₁和ω₂关于ω₀左右对称，其中初始的陷波宽度k₁为

初始的陷波深度k₂为

初始的ω₂和ω₁根据初始k₁和k₂求得。In the above formula,

k ₁ is the notch width, k ₂ is the notch depth,

k ₁ =5k ₂ , ω ₀ is the initial center frequency of the residual vibration of the servo system, calculated according to the amplitude data; ω ₁ and ω ₂ are the start and end suppression frequencies of the notch filter, respectively, ω ₁ and ω ₂ is symmetrical about ω ₀ , where the initial notch width k ₁ is

The initial notch depth k ₂ is

The initial ω ₂ and ω ₁ are obtained from the initial k ₁ and k ₂ .

Further, the method for calculating and obtaining the center frequency of the residual vibration of the servo system according to the amplitude data is as follows:

S201: obtain a displacement-time relationship diagram of the vibration of the servo system according to the amplitude data of the position sensor; and obtain the maximum wave peak occurrence time t ₁ and the second largest wave peak appearance time t ₂ of the amplitude according to the displacement time relationship diagram;

S202: According to t ₁ and t ₂ , the frequency calculation formula is used to obtain the vibration center frequency ω ₀ of the servo system; the calculation formula is shown in formula (3):

Further, in step S105, the method for judging whether the current servo system has residual vibration according to the amplitude data of the servo system after the vibration suppression is:

Obtain the maximum amplitude Hmax1 in the amplitude data of the servo system after vibration suppression; whether the judgment condition Hmax1≥x is satisfied? If so, it is determined that there is residual vibration; otherwise, it is determined that there is no residual vibration; where x is greater than 0, which is the vibration threshold and is a preset value.

Further, in step S107, according to the relationship between the first center frequency ω' ₀ and the initial center frequency ω ₀ , the method for online parameter updating of the notch filter is:

陷波宽度调整为：

陷波深度调整为：

其中，

ω′₁＝2ω′₀-ω′₂；If ω' ₀ <ω ₀ ; then the initial center frequency ω ₀ is adjusted to be equal to the first center frequency ω' ₀ , and the first center frequency ω' ₀ is adjusted to

The notch width is adjusted to:

The notch depth is adjusted to:

in,

ω′ ₁ =2ω′ ₀ −ω′ ₂ ;

陷波深度调整为调整后的陷波宽度的1/5；If ω′ ₀ =ω ₀ ; both ω ₀ and ω′ ₀ remain unchanged, the notch width is adjusted to the original notch width

The notch depth is adjusted to 1/5 of the adjusted notch width;

陷波宽度调整为：

陷波深度调整为：

If ω′ ₀ >ω ₀ , adjust the initial center frequency ω ₀ to be equal to the first center frequency ω′ ₀ , and adjust the first center frequency ω′ ₀ to be

The notch width is adjusted to:

The notch depth is adjusted to:

Further, a kind of variable load servo system vibration suppression system based on notch filter is characterized in that: comprise the following modules:

A model building module is used to model the elastic connection device of the servo system that needs to suppress vibration to obtain a servo system model; a position sensor for measuring the amplitude of the system is installed in the servo system;

a first data acquisition module, used for acquiring the amplitude data of the position sensor in the servo system;

The first judgment module is used to judge whether there is residual vibration in the system according to the amplitude data? If so, go to the filter design module; otherwise, return to the first data acquisition module;

The filter design module is used to design a notch filter according to the servo system model, and use the designed notch filter to suppress the residual vibration of the servo system; the initial center frequency of the residual vibration of the servo system is ω ₀ , calculated according to the amplitude data;

The second judgment module is used to obtain the amplitude data of the servo system after the residual vibration is suppressed by using the position sensor; and judge whether the current servo system has residual vibration according to the amplitude data of the servo system after the vibration suppression? If so, go to the calculation module; otherwise, return to the first data acquisition module;

a calculation module, used for calculating the first center frequency ω′ ₀ of the residual vibration of the servo system after the vibration suppression according to the amplitude data of the servo system after the vibration suppression;

a parameter updating module, used for online parameter updating of the notch filter according to the relationship between ω′ ₀ and ω ₀ ;

The third judgment module is used to judge whether the system is stopped? If so, go to the termination module; otherwise, use the updated notch filter to suppress the residual vibration of the system again, and return to the parameter update module;

Termination module to end the residual vibration suppression procedure.

The beneficial effects brought by the technical solution provided by the present invention are: the time domain analysis method adopted by the technical solution provided by the present invention can quickly detect the change of the center frequency, and the center frequency can be obtained one cycle after the load change produces vibration, It has strong real-time performance, and real-time correction of filter parameters and center frequency according to subsequent vibration conditions can obtain excellent filtering effect. In the case of variable load, it is a simple and real-time vibration suppression method.

Description of drawings

The present invention will be further described below in conjunction with the accompanying drawings and embodiments, in which:

1 is a flowchart of a vibration suppression method for a variable load servo system based on a notch filter in an embodiment of the present invention;

2 is a block diagram of a position loop system model with an elastic device in an embodiment of the present invention;

3 is a system structure diagram of adding a notch filter in an embodiment of the present invention;

Fig. 4 is the displacement time relation diagram of servo system vibration in the embodiment of the present invention;

5 is a comparison diagram before and after adjustment of the notch filter parameters in the embodiment of the present invention;

FIG. 6 is a schematic diagram of the module composition of a vibration suppression system of a variable load servo system based on a notch filter in an embodiment of the present invention.

Detailed ways

In order to have a clearer understanding of the technical features, objects and effects of the present invention, the specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

Embodiments of the present invention provide a method and system for suppressing vibration of a variable load servo system based on a notch filter.

Please refer to FIG. 1. FIG. 1 is a flowchart of a method for suppressing vibration of a variable load servo system based on a notch filter in an embodiment of the present invention, which specifically includes the following steps:

S101: Modeling an elastic connection device of a servo system that needs to suppress vibration to obtain a servo system model; a position sensor for measuring the amplitude of the system is installed in the servo system;

S102: Acquire the amplitude data of the position sensor in the servo system;

S103: Determine whether the system has residual vibration according to the amplitude data? If yes, go to step S104; otherwise, go back to step S102;

S104: Design a notch filter according to the servo system model, and use the designed notch filter to suppress the residual vibration of the servo system; the initial center frequency of the residual vibration of the servo system is ω ₀ , according to the amplitude data calculation;

S105: Use the position sensor to obtain the amplitude data of the servo system after the residual vibration is suppressed; and judge whether there is residual vibration in the current servo system according to the amplitude data of the servo system after the vibration suppression? If yes, go to step S106; otherwise, go back to step S102;

S106: According to the amplitude data of the servo system after the vibration suppression, calculate the first center frequency ω' ₀ of the residual vibration of the servo system after the vibration suppression;

S107: According to the relationship between ω' ₀ and ω ₀ , perform online update configuration on the parameters of the notch filter, and determine whether the system is stopped? If so, go to step S108; otherwise, use the updated notch filter to suppress the residual vibration of the system again, and return to step S105;

S108: End the residual vibration suppression program.

In step S101, the time-domain representation and frequency-domain representation of the transfer function between the motor loads and rotational speeds of the servo system model are shown in formula (1) and formula (2):

In formula (1) and formula (2), C ₁ is the damping coefficient of the motor shaft; C ₂ is the load damping coefficient; C _w is the damping coefficient of the transmission shaft; J ₁ is the moment of inertia of the motor shaft (kg·m ² ); J ₂ is the moment of inertia of the load (kg·m ² ); ω ₁ is the rotation speed of the motor shaft (rad/s); ω ₂ is the rotation speed of the load (rad/s); θ ₁ is the rotation angle of the motor shaft (rad); θ ₂ is the rotation angle of the load ( rad); T _e is the electromagnetic torque of the motor (N m); T _l is the electromagnetic torque of the motor (N m); _Tw is the torque of the transmission shaft (N m); K is the torsional elasticity coefficient of the transmission shaft (N·m/rad).

The block diagram of the position loop system model of the servo system is shown in Figure 2, and the structure of the servo system with a notch filter is shown in Figure 3.

In step S103, the method for judging whether the system has residual vibration according to the amplitude data is: obtaining the maximum amplitude Hmax in the amplitude data; whether the judgment condition Hmax≥x is established? If yes, it is determined that there is residual vibration; otherwise, it is determined that there is no residual vibration; wherein, x is greater than 0, which is the vibration threshold, and is a preset value.

In step S104, the transfer function of the designed notch filter is shown in formula (3):

k₁为陷波宽度，k₂为陷波深度，

k₁＝5k₂，ω₀为伺服系统残余振动的初始中心频率，根据所述振幅数据计算获得；ω₁和ω₂分别为陷波滤波器的起始抑制频率和终止抑制频率，其中初始的陷波宽度k₁为

初始的陷波深度k₂为

初始的ω₂和ω₁根据初始k₁和k₂求得。In the above formula,

k ₁ is the notch width, k ₂ is the notch depth,

k ₁ =5k ₂ , ω ₀ is the initial center frequency of the residual vibration of the servo system, calculated according to the amplitude data; ω ₁ and ω ₂ are the start and end suppression frequencies of the notch filter, respectively, where the initial The notch width _k1 is

The initial notch depth k ₂ is

The initial ω ₂ and ω ₁ are obtained from the initial k ₁ and k ₂ .

The method for calculating and obtaining the center frequency of the residual vibration of the servo system according to the amplitude data is as follows:

S201: according to the amplitude data of the position sensor, obtain the displacement-time relationship diagram of the vibration of the servo system (as shown in Figure 4); and obtain the maximum wave peak appearance time _t1 and the second largest wave peak appearance time _t2 of the amplitude according to the displacement time relationship diagram;

S202: According to t ₁ and t ₂ , the frequency calculation formula is used to obtain the vibration center frequency ω ₀ of the servo system; the calculation formula is shown in formula (4):

In step S105, the method for judging whether there is residual vibration in the current servo system according to the amplitude data of the servo system after the vibration suppression is:

Obtain the maximum amplitude Hmax1 in the amplitude data of the servo system after vibration suppression; whether the judgment condition Hmax1≥x is satisfied? If so, it is determined that there is residual vibration; otherwise, it is determined that there is no residual vibration; wherein, x is a vibration threshold greater than 0, which is a preset value.

In step S106, the steps of calculating the vibration center frequency _ω'0 of the servo system after vibration suppression are as follows:

S301: According to the amplitude data of the servo system after the vibration suppression, obtain a _first displacement time relationship diagram of the vibration of the servo system after the vibration suppression; The time t ₂ ′ when the wave peak appears;

S302: According to t ₁ ' and t ₂ ', the frequency calculation formula is used to calculate the vibration center frequency ω' ₀ of the servo system after vibration suppression; the calculation formula is shown in formula (5):

In step S107, according to the relationship between ω' ₀ and ω ₀ , the method for online parameter update configuration of the notch filter is:

The comparison diagram of filter parameters before and after online update is shown in Figure 5. The dotted line in the figure is the notch filter after updating, and the solid line is the notch filter before updating. It can be seen that the subsequent parameter ω′ ₀ is on the left side of the initial center frequency ω ₀ , so the adjusted first center frequency adjusted to ω″ ₀ should also be shifted to the left, and the notch width should be reduced accordingly. The parameters of the notch filter are updated in the following three cases:

中心频率向左偏移，陷波宽度调整策略为：

为保证幅频特性对称性，取ω′₁＝2ω′₀-ω′₂。经过调整，陷波带宽逐步变窄，对周围频率的响应影响变小。Case 1: ω' ₀ <ω ₀ , at this time, the initial center frequency ω ₀ is adjusted to be equal to the first center frequency ω' ₀ , and the first center frequency ω' ₀ is adjusted as

The center frequency is shifted to the left, and the notch width adjustment strategy is:

In order to ensure the symmetry of the amplitude-frequency characteristic, take ω′ ₁ =2ω′ ₀ -ω′ ₂ . After adjustment, the notch bandwidth is gradually narrowed, and the effect on the response of surrounding frequencies is reduced.

然后继续分析后续振动情况。Case 2: ω′ ₀ =ω ₀ , the center frequency of the filter is relatively accurate at this time and does not need to be changed, but the notch width is correspondingly narrowed, the method is similar to the case 1, the difference is that the bandwidth is directly reduced to the original of

Then continue to analyze subsequent vibrations.

但与情况一相反，中心频率向右偏移。此时中心频率，左右陷波宽度调整与情况一相同，左边频率调整为

右边频率调整为ω′₂＝2ω₀-ω′₁。Case 3: ω′ ₀ >ω ₀ , then adjust the initial center frequency ω ₀ to be equal to the first center frequency ω′ ₀ , and adjust the first center frequency ω′ ₀ to be

But contrary to case 1, the center frequency is shifted to the right. At this time, the center frequency, the left and right notch width adjustment are the same as in case 1, and the left frequency adjustment is

The right frequency is adjusted to ω' ₂ =2ω ₀ -ω' ₁ .

The bandwidth is determined by ω′ ₁ and ω′ ₂ , thereby the parameters k ₁ and k ₂ of the notch filter are determined, and then the parameters a, b and c are determined by the center frequency ω′ ₀ to complete the configuration of the filter.

Please refer to FIG. 6 , which is a schematic diagram of the module composition of a vibration suppression system of a variable load servo system based on a notch filter according to an embodiment of the present invention. module 12, first judgment module 13, filter design module 14, second judgment module 15, calculation module 16, parameter update module 17, third judgment module 18 and termination module 19;

The model building module 11 is used to model the elastic connection device of the servo system that needs to suppress vibration to obtain a servo system model; a position sensor for measuring the amplitude of the system is installed in the servo system;

The first data acquisition module 12 is used to acquire the amplitude data of the position sensor in the servo system;

The first judgment module 13 is used to judge whether there is residual vibration in the system according to the amplitude data? If so, go to the filter design module 14; otherwise, return to the first data acquisition module 12;

The filter design module 14 is used to design a notch filter according to the servo system model, and use the designed notch filter to suppress the residual vibration of the servo system; the initial center frequency of the residual vibration of the servo system is ω ₀ , calculated according to the amplitude data;

The second judgment module 15 is used to obtain the amplitude data of the servo system after the residual vibration is suppressed by using the position sensor; and judge whether the current servo system has residual vibration according to the amplitude data of the servo system after the vibration suppression? If so, go to the calculation module 16; otherwise, return to the first data acquisition module 12;

The calculation module 16 is used for calculating the first center frequency ω' ₀ of the residual vibration of the servo system after the vibration suppression according to the amplitude data of the servo system after the vibration suppression;

The parameter updating module 17 is used to update the parameters of the notch filter online according to the relationship between ω′ ₀ and ω ₀ ;

The third judging module 18 is used to judge whether the system is stopped? If so, go to the termination module; otherwise, use the updated notch filter to suppress the residual vibration of the system again, and return to the parameter update module;

The termination module 19 is used to end the residual vibration suppression procedure.

The beneficial effects of the present invention are as follows: the time domain analysis method adopted by the technical solution of the present invention can quickly detect the change of the center frequency, and the center frequency can be obtained in one cycle after the vibration is generated by the load change, and the real-time performance is strong, and according to the Real-time correction of filter parameters and center frequency for subsequent vibration conditions can obtain excellent filtering effects. In the case of variable loads, it is a simple and real-time vibration suppression method.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (7)

1. a variable load servo system vibration suppression method based on a notch filter, is characterized in that: comprise the following steps: S101: Modeling an elastic connection device of a servo system that needs to suppress vibration to obtain a servo system model; a position sensor for measuring the amplitude of the system is installed in the servo system; S102: Acquire the amplitude data of the position sensor in the servo system; S103: Determine whether the system has residual vibration according to the amplitude data? If yes, go to step S104; otherwise, go back to step S102; S104: Design a notch filter according to the servo system model, and use the designed notch filter to suppress the residual vibration of the servo system; the initial center frequency of the residual vibration of the servo system is ω ₀ , according to the amplitude data calculation; S105: Use the position sensor to obtain the amplitude data of the servo system after the residual vibration is suppressed; and judge whether there is residual vibration in the current servo system according to the amplitude data of the servo system after the vibration suppression? If yes, go to step S106; otherwise, go back to step S102; S106: According to the amplitude data of the servo system after the vibration suppression, calculate and obtain the first center frequency ω′ ₀ of the residual vibration of the servo system after the vibration suppression; S107: According to the relationship between ω′ ₀ and ω ₀ , update the parameters of the notch filter online; S108: Determine whether the servo system is stopped? If so, go to step S109; otherwise, use the updated notch filter to suppress the residual vibration of the system again, and return to step S107; S109: End the residual vibration suppression program; In step S107, according to the relationship between the first center frequency ω' ₀ and the initial center frequency ω ₀ , the method for online parameter updating of the notch filter is: If ω′ ₀ <ω ₀ ; then the initial center frequency ω ₀ is adjusted to be equal to the first center frequency ω′ ₀ , and the first center frequency ω′ ₀ is adjusted to

The notch width is adjusted to:

The notch depth is adjusted to:

in,

ω′ ₁ =2ω′ ₀ −ω′ ₂ ; If ω′ ₀ =ω ₀ ; both ω ₀ and ω′ ₀ remain unchanged, the notch width k ₁ is adjusted to the original notch width

The notch depth k ₂ is adjusted to 1/5 of the adjusted notch width; If ω′ ₀ >ω ₀ , the initial center frequency ω ₀ is adjusted to be equal to the first center frequency ω′ ₀ , and the first center frequency ω′ ₀ is adjusted to

The notch width k ₁ is adjusted to:

The notch depth k ₂ is adjusted to:

ω ₁ and ω ₂ are the start and end rejection frequencies of the notch filter, respectively. 2. a kind of variable load servo system vibration suppression method based on notch filter as claimed in claim 1, is characterized in that: in step S101, the transfer function between the load speed of the motor of the servo system model is such as formula (1) shown:

In the above formula, J ₂ is the moment of inertia of the load; θ ₁ is the rotation angle of the motor shaft; θ ₂ is the load rotation angle; K is the torsional elasticity coefficient of the transmission shaft. 3. a kind of variable load servo system vibration suppression method based on notch filter as claimed in claim 1 is characterized in that: in step S103, the method for judging whether there is residual vibration in the system according to amplitude data is: obtaining the amplitude The maximum amplitude Hmax in the data; is the judgment condition Hmax≥x true? If yes, it is determined that there is residual vibration; otherwise, it is determined that there is no residual vibration; wherein, x is greater than 0, which is the vibration threshold, and is a preset value. 4. a kind of variable load servo system vibration suppression method based on notch filter as claimed in claim 1, is characterized in that: in step S104, the transfer function of the notch filter of design is as shown in formula (2):

In the above formula,

k ₁ is the notch width, k ₂ is the notch depth,

k ₁ =5k ₂ , ω ₀ is the initial center frequency of the residual vibration of the servo system, calculated according to the amplitude data; ω ₁ and ω ₂ are the start and end suppression frequencies of the notch filter, respectively, ω ₁ and ω 2 ω ₂ is symmetrical about ω ₀ , where the initial notch width k ₁ is

The initial notch depth k ₂ is

The initial ω ₂ and ω ₁ are obtained from the initial k ₁ and k ₂ . 5. a kind of variable load servo system vibration suppression method based on notch filter as claimed in claim 4, is characterized in that: in step S104, the method that obtains the center frequency of servo system residual vibration according to described amplitude data calculation is as follows : S201: obtain a displacement-time relationship diagram of the vibration of the servo system according to the amplitude data of the position sensor; and obtain the maximum wave peak occurrence time t ₁ and the second largest wave peak appearance time t ₂ of the amplitude according to the displacement time relationship diagram; S202: According to t ₁ and t ₂ , the initial center frequency ω ₀ of the residual vibration of the servo system is obtained by using the frequency calculation formula; the calculation formula is shown in formula (3):

6. a kind of variable load servo system vibration suppression method based on notch filter as claimed in claim 1 is characterized in that: in step S105, according to the amplitude data of the servo system after vibration suppression, judge whether the current servo system has residual The way to vibrate is: Obtain the maximum amplitude Hmax1 in the amplitude data of the servo system after vibration suppression; whether the judgment condition Hmax1≥x is satisfied? If so, it is determined that there is residual vibration; otherwise, it is determined that there is no residual vibration; where x is greater than 0, which is the vibration threshold and is a preset value. 7. A variable load servo system vibration suppression system based on a notch filter, characterized in that: comprising the following modules: A model building module is used to model the elastic connection device of the servo system that needs to suppress vibration to obtain a servo system model; a position sensor for measuring the amplitude of the system is installed in the servo system; a first data acquisition module, used for acquiring the amplitude data of the position sensor in the servo system; The first judgment module is used to judge whether there is residual vibration in the system according to the amplitude data? If so, go to the filter design module; otherwise, return to the first data acquisition module; The filter design module is used to design a notch filter according to the servo system model, and use the designed notch filter to suppress the residual vibration of the servo system; the initial center frequency of the residual vibration of the servo system is ω ₀ , calculated according to the amplitude data; The second judgment module is used to obtain the amplitude data of the servo system after the residual vibration is suppressed by using the position sensor; and judge whether the current servo system has residual vibration according to the amplitude data of the servo system after the vibration suppression? If so, go to the calculation module; otherwise, return to the first data acquisition module; a calculation module, used for calculating the first center frequency ω′ ₀ of the residual vibration of the servo system after the vibration suppression according to the amplitude data of the servo system after the vibration suppression; a parameter updating module, used for online parameter updating of the notch filter according to the relationship between ω′ ₀ and ω ₀ ; The third judgment module is used to judge whether the system is stopped? If so, go to the termination module; otherwise, use the updated notch filter to suppress the residual vibration of the system again, and return to the parameter update module; Termination module for ending the residual vibration suppression procedure; In the parameter update module, according to the relationship between the first center frequency ω′ ₀ and the initial center frequency ω ₀ , the method for online parameter update of the notch filter is as follows: If ω′ ₀ <ω ₀ ; then the initial center frequency ω ₀ is adjusted to be equal to the first center frequency ω′ ₀ , and the first center frequency ω′ ₀ is adjusted to

The notch width k ₁ is adjusted to:

The notch depth k ₂ is adjusted to:

in,

ω′ ₁ =2ω′ ₀ −ω′ ₂ ; If ω′ ₀ =ω ₀ ; both ω ₀ and ω′ ₀ are unchanged, the notch width is adjusted to the original notch width

The notch depth is adjusted to 1/5 of the adjusted notch width; If ω′ ₀ >ω ₀ , the initial center frequency ω ₀ is adjusted to be equal to the first center frequency ω′ ₀ , and the first center frequency ω′ ₀ is adjusted to

The notch width k ₁ is adjusted to:

The notch depth k ₂ is adjusted to:

ω ₁ and ω ₂ are the start and end rejection frequencies of the notch filter, respectively.

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