CN111810566A - Magnetic guide rail vibration absorber and vibration reduction method thereof - Google Patents

Abstract

The invention discloses a magnetic guide rail vibration absorber and a vibration reduction method thereof. The vibration absorber comprises a bracket and two mutually perpendicular and fixedly connected magnetic guide rails. The bottom of the bracket is fixed on a motor, and the upper end of the bracket is connected to the two magnetic guide rails. The nodes are fixedly connected to support the magnetic guide rails, the end of each magnetic guide rail is slidably connected with a mass block, and a spring is connected between each of the mass blocks and the connection nodes of the two magnetic guide rails, and the spring is wound around the magnetic rail. On the guide rail, the mass block is a coil wound with the magnetic guide rail as the central axis, and the two ends of the coil are connected with a resistance R through a wire; the advantage of the present invention is that the energy generated by the vibration is consumed in the resistance R, thereby reducing the vibration energy of the motor , to achieve better vibration reduction effect.

Description

Magnetic guide rail vibration absorber and vibration reduction method thereof

technical field

The invention relates to the technical field of vibration reduction of vertical rotating equipment, and more particularly to a magnetic guide rail vibration absorber and a vibration reduction method thereof.

Background technique

At present, in the process of industrial production, some large-scale motors are often modified by frequency conversion for energy saving reasons. For vertical motors, the support stiffness in the horizontal direction is weak; the shaft system is long, and the critical speed is generally lower than its power frequency operation. Rotating speed. This results in that after the frequency conversion transformation of the vertical motor, the operating speed of the equipment often falls within its critical speed range, causing the upper part of the motor to vibrate beyond the standard.

At present, there are two commonly used methods to deal with critical vibration: one is to reduce the unbalance amount of the shafting through dynamic balance, reduce the unbalanced excitation force of the shafting, and reduce the unbalanced vibration response at the critical speed. This method The vibration amplitude of the critical speed can be reduced to a certain extent, but it requires a very high balance accuracy to control the vibration amplitude of the shafting at the critical speed to reach the qualified range; the second method is to strengthen the fixed support strength of the upper part of the motor to suppress The vibration response at the critical speed is generally supported by the top wire in the field. However, this method is not easy to control the support strength of each point to achieve the same consistency. In the case of poor control, it is easy to cause the shaft centerline to be inconsistent, which not only fails to achieve the vibration reduction effect, but aggravates the vibration. At the same time, when the vibration is too large, the rigid support may also cause damage to the equipment.

Chinese Patent Publication No. CN203670596U, discloses a simply supported beam type dynamic vibration absorber with adjustable frequency, including a base, a stepping motor, a slider, a drive screw, and a metal beam. The base is provided with a dovetail groove, and the slider The lower end of the slider is a dovetail structure, the upper end of the slider is a support arm with a hole, and the middle of the slider is a threaded through hole. There are two sliders, and the lower ends of the two sliders are installed In the dovetail groove, there is a concentrated mass block in the middle of the metal beam, the two ends of the metal beam respectively pass through the holes of the upper end support arms of the two sliders, and reverse threads are symmetrically arranged on the outer wall of the drive screw, and the drive screw passes through the two blocks. A through hole in the middle of the slider is matched with the threads of the two through holes, and the first end of the drive screw is connected to the stepping motor. Compared with cantilever vibration absorbers, the need for outward extension space is reduced. However, the patented vibration absorber itself has a complex structure and many components, which may easily lead to the vibration absorber becoming a new vibration source, and the vibration reduction effect is not good.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention lies in the problem that the vibration absorber of the prior art vertical rotating equipment has a poor vibration damping effect.

The present invention solves the above technical problems by the following technical means: a magnetic guide rail vibration absorber, comprising a bracket and two mutually perpendicular and fixedly connected magnetic guide rails, the bottom of the bracket is fixed on the motor, the upper end of the bracket is connected to the two magnetic guide rails The connection nodes are fixedly connected to support the magnetic guide rails, the end of each guide rail is slidably connected to a mass block, and a spring is connected between each of the mass blocks and the connection nodes of the two magnetic guide rails, and the mass block is The coil is wound around the magnetic rail as the central axis, and the two ends of the coil are connected to a resistor R through wires.

In the present invention, under the action of the vibration absorber, the mass block composed of the coil performs simple harmonic vibration synchronously on the magnetic guide rail. According to the principle of electromagnetic induction, the coil cuts the magnetic field line to generate an induced electromotive force, and the coil is connected in series with a resistance R, which removes the mass block from the motor. The absorbed vibration energy is converted into the heat generated by the resistor R, and the energy generated by the vibration is consumed in the resistor R, thereby reducing the vibration energy of the motor and achieving a better vibration reduction effect.

Further, the spring is a spring damper.

Further, the bracket includes four equal-length support legs, one end of each support leg is fixed on the motor, the other end of each support leg is connected together and fixedly connected with the connection nodes of the two magnetic guide rails, and the four One end of the support leg encloses a rectangle.

Further, the motor is a motor of a vertical rotating equipment.

The present invention also provides a vibration reduction method for a magnetic guide rail vibration absorber, the method comprising:

Step 1: Obtain the vibration equation of the two-degree-of-freedom double-damping vibration system under the action of the excitation force of the motor;

Step 2: Obtain a complex equation of forced vibration in a steady state and solve the complex equation, and obtain the force of the mass acting on the upper surface of the motor according to the solution of the complex equation;

Step 3: Select the parameters of the vibration absorber so that the vibration is absorbed;

Step 4: Adjust the amplification factor so that the displacement of the motor under the action of the exciting force is the smallest in the full frequency band, that is, the complex solution of the vibration of the single-degree-of-freedom vibration system in a stable state is the smallest, and the optimal damping ratio of the vibration absorber and the optimal vibration absorber are obtained. The natural frequency of the vibration absorber.

Further, the step 1 includes:

获取在电机的激振力作用下两自由度双阻尼振动系统的振动方程；其中，M表示电机的质量，m表示质量块的质量，K表示电机的弹性系数，k表示质量块的弹性系数，C₁表示电机的阻尼系数，C₂表示质量块的阻尼系数，x₁表示电机的位移，x₂表示质量块的位移，P(t)表示激振力。Use the formula

Obtain the vibration equation of the two-degree-of-freedom double-damping vibration system under the action of the excitation force of the motor; where M represents the mass of the motor, m represents the mass of the mass block, K represents the elastic coefficient of the motor, k represents the elastic coefficient of the mass block, C ₁ represents the damping coefficient of the motor, C ₂ represents the damping coefficient of the mass block, x ₁ represents the displacement of the motor, x ₂ represents the displacement of the mass block, and P(t) represents the excitation force.

Further, the step 2 includes:

If the excitation force of the motor is a simple harmonic force, the vibration equation of the two-degree-of-freedom double-damping vibration system is transformed, and the complex equation of the forced vibration in the steady state is obtained as

Among them, ω represents the excitation frequency, i represents the complex imaginary part unit, X ₁ represents the complex variable of the displacement of the motor, X ₂ represents the complex variable of the displacement of the mass block, P represents the complex variable of the exciting force,

Solve complex equations to get

获取质量块作用于电机上表面的力，其中，F₁表示质量块作用于电机上表面的力。by formula

Obtain the force of the mass acting on the upper surface of the motor, where F ₁ represents the force acting on the upper surface of the motor by the mass.

Further, the step 3 includes:

Obtain the complex solution of the vibration of the single-degree-of-freedom vibration system in the steady state by the formula X ₁₀ =P/(K-Mω ² +iωC ₁ );

The acting force of the motor itself is obtained by the formula F ₁₀ =(K+iωC ₁ )P/(K-Mω ² +iωC ₁ ), where F ₁₀ represents the acting force of the motor itself;

获取吸振性能与激振力频率之间的关系式，其中，

ξ表示吸振系数，E₁表示质量块作用于电机以后的振动能量，E₁₀表示电机本身的振动能量，V₁表示质量块作用于电机以后振动速度的复变量，V₁₀表示电机本身振动速度的复变量；by formula

Obtain the relationship between the vibration absorption performance and the frequency of the excitation force, where,

ξ represents the vibration absorption coefficient, E ₁ represents the vibration energy after the mass block acts on the motor, E ₁₀ represents the vibration energy of the motor itself, V ₁ represents the complex variable of the vibration speed after the mass block acts on the motor, and V ₁₀ represents the vibration speed of the motor itself. complex variable;

选取吸振器的参数使得ξ>0，其中，ω_r为电机本身振动速度的复变量的最强频率。Use the strongest frequency of the complex variable of the vibration speed of the motor itself to pass the formula

The parameters of the vibration absorber are selected so that ξ>0, where ω _r is the strongest frequency of the complex variable of the vibration speed of the motor itself.

Further, the step 4 includes:

其中，β表示放大因子且make

where β represents the amplification factor and

ζ₂表示吸振器的阻尼比且

Among them, ω _n represents the natural frequency of the motor, μ represents the ratio of the mass of the mass to the motor mass, ω ₀ represents the natural frequency of the vibration absorber, ζ ₁ represents the damping ratio of the motor and

ζ ₂ represents the damping ratio of the shock absorber and

Adjust the amplification factor so that the displacement of the motor under the action of the exciting force is the smallest in the whole frequency band, that is, the complex solution of the vibration of the single-degree-of-freedom vibration system in the steady state is the smallest.

Further, the process of adjusting the amplification factor is:

Step 401 : take a frequency band γ _a ≤ω ₁ ≤γ _b in the neighborhood of the natural frequency of the motor, where γ _a =0.7ω _n , γ _b =1.3ω _n ;

Step 402: Substitute the initial value of the natural frequency of the vibration absorber and the initial value of the damping ratio of the vibration absorber into the calculation formula of the amplification factor to calculate the value of the amplification factor in the frequency band;

Step 403: Update the natural frequency of the vibration absorber and the damping ratio of the vibration absorber, take the updated natural frequency of the vibration absorber as the initial value of the natural frequency of the vibration absorber, and use the updated damping ratio of the vibration absorber as the sum of the damping ratio of the vibration absorber. The initial value, return to step 402, until the minimum value of the amplification factor is obtained, the damping ratio of the vibration absorber at this time is taken as the optimal damping ratio of the vibration absorber, and the natural frequency of the vibration absorber at this time is regarded as the optimal vibration absorption the natural frequency of the device.

The advantages of the present invention are:

(1) In the present invention, under the action of the vibration absorber, the mass block composed of the coil performs simple harmonic vibration synchronously on the magnetic guide rail. According to the principle of electromagnetic induction, the coil cuts the magnetic field line to generate an induced electromotive force, and the coil is connected in series with a resistance R. The vibration energy absorbed from the motor is converted into the heat generated by the resistor R, and the energy generated by the vibration is consumed in the resistor R, thereby reducing the vibration energy of the motor and achieving a better vibration reduction effect.

(2) The present invention selects the parameters of the vibration absorber so that the vibration is absorbed, adjusts the amplification factor to make the displacement of the motor under the action of the exciting force to be the smallest in the whole frequency band, and obtains the optimal damping ratio of the vibration absorber and the optimal vibration absorption According to the natural frequency of the device, the vibration reduction effect is analyzed and calculated to make the vibration reduction effect optimal.

Description of drawings

1 is a front view of a magnetic rail vibration absorber according to an embodiment of the present invention;

2 is a top view of a magnetic rail vibration absorber according to an embodiment of the present invention;

3 is a schematic diagram of the connection between the coil in the mass block and the resistor R in a magnetic rail vibration absorber provided by an embodiment of the present invention;

4 is a physical model of a single-degree-of-freedom single-damping vibration system in a magnetic rail vibration absorber according to an embodiment of the present invention;

5 is a physical model of a two-degree-of-freedom double-damping vibration system in a magnetic rail vibration absorber according to an embodiment of the present invention;

FIG. 6 is a flowchart of a vibration reduction method for a magnetic rail vibration absorber provided by an embodiment of the present invention.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are part of the present invention. examples, but not all examples. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

As shown in FIG. 1 to FIG. 3 , a magnetic rail vibration absorber includes a bracket 4 and two magnetic rails 2 that are perpendicular to each other and are fixedly connected.

The bracket 4 includes four supporting legs of equal length, and one end of each supporting leg is fixed on a motor 5, and the motor 5 is a motor 5 of a vertical rotating device. The other ends of each support leg are connected together and fixedly connected with the connection nodes of the two magnetic guide rails 2 , and one end of the four support legs forms a rectangle.

The upper end of the bracket 4 is fixedly connected with the connection nodes of the two magnetic guide rails 2 to support the magnetic guide rails 2. The two magnetic guide rails 2 are perpendicular to each other, corresponding to the working medium flow direction and the vertical working medium flow direction of the vertical motor 5 respectively. The shape vibration absorber can adjust the frequency parameters separately, corresponding to different vibration frequencies in two directions, and improve the vibration reduction effect.

A mass block 1 is slidably connected to the end of each magnetic guide rail 2 , and the weight of the mass block 1 can be adjusted by replacement to improve the frequency width of damping.

A spring 3 is connected between each of the connection nodes of the mass 1 and the two magnetic guide rails 2 , and the spring 3 is a spring damper. The spring 3 is wound on the magnetic guide rail 2, the mass block 1 is a coil wound around the magnetic guide rail as the central axis, and two ends of the coil are connected to a resistor R (not shown in the figure) through wires.

Continue to refer to Figures 1 to 3, the vibration absorbers are arranged according to the working fluid flow direction (X direction) and the vertical working fluid flow direction (Y direction) of the motor 5. When the motor 5 vibrates greatly, the vibration in the X direction causes the mass block C The vibration absorber group composed of the mass block D and the spring damper vibrates. According to the relevant parameters of the main system with the motor 5 as the main body, the appropriate elastic coefficients of the mass blocks C, D and the spring damper are designed to make the attached vibration absorber system. Absorb part of the main system X-direction vibration energy to achieve the effect of reducing the X-direction vibration amplitude.

In the same way, the vibration absorber group composed of the mass blocks A, B and the spring damper can absorb the vibration energy in the Y direction and reduce the effect of the vibration amplitude in the Y direction.

In the plane composed of the mutually perpendicular X and Y directions, the vibrations in all directions can be decomposed into the synthesis of the vibrations in the X and Y directions. The purpose of the vibration amplitude.

Under the action of the vibration absorber, the mass block 1 composed of the coil performs simple harmonic vibration synchronously on the magnetic guide 2. According to the principle of electromagnetic induction, the coil cuts the magnetic field line to generate an induced electromotive force, and the coil series resistance R, The vibration energy absorbed by the mass block 1 from the motor 5 is converted into the heat generated by the resistor R, and the energy generated by the vibration is consumed in the resistor R, thereby reducing the vibration energy of the motor and achieving a better vibration reduction effect.

Ignoring the influence of some secondary factors, the motor 5 can be simplified to the physical model of the single-degree-of-freedom and single-damping vibration system shown in Figure 4. If a vibration absorber composed of k~m~C2 is added, it becomes Figure 5 The shown two-degree-of-freedom double-damping vibration system, as shown in Figure 6, the present invention also provides a vibration reduction method for a magnetic rail vibration absorber, the method comprising:

Step S1: Obtain the vibration equation of the two-degree-of-freedom double-damping vibration system under the action of the excitation force of the motor 5; the specific process is:

获取在电机5的激振力作用下两自由度双阻尼振动系统的振动方程(不计重力及产生的初位移)；其中，M表示电机5的质量，m表示质量块1的质量，K表示电机5的弹性系数，k表示质量块1的弹性系数，C₁表示电机5的阻尼系数，C₂表示质量块1的阻尼系数，x₁表示电机5的位移，x₂表示质量块1的位移，P(t)表示激振力。Use the formula

Obtain the vibration equation of the two-degree-of-freedom double-damping vibration system under the action of the excitation force of the motor 5 (regardless of the gravity and the resulting initial displacement); where M represents the mass of the motor 5, m represents the mass of the mass block 1, and K represents the motor The elastic coefficient of 5, k is the elastic coefficient of mass 1, C ₁ is the damping coefficient of motor 5, C ₂ is the damping coefficient of mass 1, x ₁ is the displacement of motor 5, x ₂ is the displacement of mass 1, P(t) represents the excitation force.

Step S2: obtaining a complex equation of forced vibration in a steady state and solving the complex equation, and obtaining the force of the mass 1 acting on the upper surface of the motor 5 according to the solution of the complex equation; the specific process is:

The exciting force P(t) of mechanical vibration is usually a periodic external force. If the excitation force of the motor 5 is a simple harmonic force, the vibration equation of the two-degree-of-freedom double-damping vibration system is transformed, and the complex equation of the forced vibration in the steady state is obtained as:

Among them, ω represents the excitation frequency, i represents the complex imaginary part unit, X ₁ represents the complex variable of the displacement of the motor 5, X ₂ represents the complex variable of the displacement of the mass 1, P represents the complex variable of the exciting force, and solves the complex equation have to

获取质量块1作用于电机5上表面的力，其中，F₁表示质量块1作用于电机5上表面的力。by formula

Obtain the force of the mass 1 acting on the upper surface of the motor 5 , where F ₁ represents the force of the mass 1 acting on the upper surface of the motor 5 .

Step S3: select the parameters of the vibration absorber so that the vibration is absorbed; the specific process is:

Obtain the complex solution of the vibration of the single-degree-of-freedom vibration system in the steady state by the formula X ₁₀ =P/(K-Mω ² +iωC ₁ );

The force of the motor 5 itself is obtained by the formula F ₁₀ =(K+iωC ₁ )P/(K-Mω ² +iωC ₁ ), where F ₁₀ represents the force of the motor 5 itself; it is equivalent to m= 0, the case of C2=0.

Under the same excitation force, whether or not a vibration absorber composed of k~m~C2 is attached, the vibration energy E1 of the motor 5 and the force F1 of the mass 1 acting on the upper surface of the motor 5 are usually different, and the change is different from the excitation force. The frequency of the vibration force is directly related. The following is a detailed analysis of the relationship between the vibration absorption performance of the vibration absorber and the frequency of the excitation force (ie, the frequency characteristics of vibration absorption).

获取吸振性能与激振力频率之间的关系式，其中，

ξ表示吸振系数，E₁表示质量块1作用于电机5以后的振动能量，E₁₀表示电机5本身的振动能量，V₁表示质量块1作用于电机5以后振动速度的复变量，V₁₀表示电机5本身振动速度的复变量；by formula

Obtain the relationship between the vibration absorption performance and the frequency of the excitation force, where,

ξ represents the vibration absorption coefficient, E ₁ represents the vibration energy after the mass block 1 acts on the motor 5, E ₁₀ represents the vibration energy of the motor 5 itself, V ₁ represents the complex variable of the vibration speed after the mass block 1 acts on the motor 5, and V ₁₀ represents The complex variable of the vibration speed of the motor 5 itself;

Obviously ξ>-1, when ξ>0, F ₁₀ /F ₁ (or E ₁₀ /E ₁ )>1, indicating that the vibration of the K~M~C1 damping vibration system is "absorbed" after the vibration absorber is attached ; When -1<ξ<0, F ₁₀ /F ₁ (or E ₁₀ /E ₁ )<1, the vibration of K～M～C1 damping vibration system is strengthened after adding damping vibration absorber; when When ξ=0, F ₁₀ /F ₁ (or E ₁₀ /E ₁ )=1, indicating that the damping vibration absorber has no effect on the K-M-C1 vibration system.

Therefore, the principle of designing a vibration absorber is to select appropriate parameters of k, m, and C2 so that ξ>0.

When the mechanical system is running, the frequency spectrum of its vibration (such as the vibration speed V ₁₀ ) can be measured, then the vibration absorber k～m～C2 vibration system can be attached to the machine, and the size of the parameters k, m and C2 can be appropriately selected to make the interval (ω _min , ω _max ) contain as many frequencies as possible with strong vibration in V ₁₀ , so that a part of the vibration energy of the mechanical damping vibration system K～M～C1 is absorbed by the vibration absorber and consumed in the damping C2, and the mechanical vibration is reduced.

和固有频率

之间，即：Select the component with stronger vibration in V ₁₀ , set its frequency as ω _r , and select the parameters k, m and C2 of the vibration absorber so that ω _r is located at its damping natural frequency

and natural frequency

between, namely:

but:

At this time, the vibration component of the mechanical system at the frequency ω _r is weakened to a considerable extent, and the vibration energy can be attenuated to different degrees in the relatively large frequency domain on both sides of ω _r , so that the total vibration is weakened.

When selecting vibration absorber parameters, the larger the value of k, m, and C2, the larger the frequency range of vibration absorption (ω _min , ω _max ), and the better the vibration absorption effect. However, when k, m, and C2 are too large, it may be difficult to arrange the vibration absorber on the mechanical system, and the vibration absorber itself becomes a new vibration source. Therefore, usually should make m≤M, k≤K, and properly adjust the size of k, m, C2, so that it is in the best vibration absorption state.

Step S4: Adjust the amplification factor so that the displacement of the motor 5 under the action of the exciting force is the smallest in the whole frequency band, that is, the complex solution of the vibration of the single-degree-of-freedom vibration system in a stable state is the smallest, and the optimal damping ratio of the vibration absorber and the optimal vibration absorber are obtained. the natural frequency of the vibration absorber. The specific process is:

其中，β表示放大因子且make

where β represents the amplification factor and

ζ₂表示吸振器的阻尼比且

Among them, ω _n represents the natural frequency of the motor 5, μ represents the ratio of the mass of the mass block 1 to the mass of the motor 5, ω ₀ represents the natural frequency of the vibration absorber, ζ ₁ represents the damping ratio of the motor 5 and

ζ ₂ represents the damping ratio of the shock absorber and

The amplification factor is adjusted so that the displacement of the motor 5 under the action of the exciting force is minimized in the full frequency band, that is, the complex solution of the vibration of the single-degree-of-freedom vibration system in a stable state is minimized.

Wherein, the process of adjusting the amplification factor is:

Step 401 : take a frequency band γ _a ≤ω ₁ ≤γ _b in the neighborhood of the natural frequency of the motor 5 , where γ _a =0.7ω _n , γ _b =1.3ω _n ;

Step 402: Substitute the initial value of the natural frequency of the vibration absorber and the initial value of the damping ratio of the vibration absorber into the calculation formula of the amplification factor to calculate the value of the amplification factor in the frequency band;

Step 403: Update the natural frequency of the vibration absorber and the damping ratio of the vibration absorber, take the updated natural frequency of the vibration absorber as the initial value of the natural frequency of the vibration absorber, and use the updated damping ratio of the vibration absorber as the sum of the damping ratio of the vibration absorber. The initial value, return to step 402, until the minimum value of the amplification factor is obtained, the damping ratio of the vibration absorber at this time is taken as the optimal damping ratio of the vibration absorber, and the natural frequency of the vibration absorber at this time is regarded as the optimal vibration absorption the natural frequency of the device.

The above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The recorded technical solutions are modified, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. The utility model provides a magnetism guide rail bump leveller which characterized in that, includes support and two mutually perpendicular and fixed connection's magnetism guide rail, the support bottom is fixed on the motor, and the support upper end is connected with the connected node fixed connection of two magnetism guide rails, supports the magnetism guide rail, the equal sliding connection mass block of tip of every magnetism guide rail, every all be connected with a spring between the connected node of mass block and two magnetism guide rails, the spring winding is on the magnetism guide rail, and the mass block is for using magnetism guide rail as the winding coil of center pin, and a resistance R is passed through the wire at the both ends of coil.

2. The magnetic rail vibration absorber of claim 1 wherein said spring is a spring damper.

3. The magnetic guide rail vibration absorber according to claim 1 wherein the bracket comprises four equal length support legs, one end of each support leg is fixed to the motor, the other end of each support leg is connected together and fixedly connected to the connection node of the two magnetic guide rails, and one end of each of the four support legs is enclosed into a rectangle.

4. The magnetic rail vibration absorber of claim 1 wherein said motor is a motor of a vertical rotating apparatus.

5. The method for damping vibration of a magnetic rail vibration absorber according to any one of claims 1 to 4, wherein the method comprises:

the method comprises the following steps: acquiring a vibration equation of a two-degree-of-freedom double-damping vibration system under the action of an excitation force of a motor;

step two: acquiring a complex equation of forced vibration in a stable state, solving the complex equation, and acquiring the force of a mass block acting on the upper surface of the motor according to the solution of the complex equation;

step three: selecting parameters of the vibration absorber to enable vibration to be absorbed;

step four: and adjusting the amplification factor to minimize the displacement of the motor under the action of the exciting force on a full frequency band, namely minimizing a complex solution of the vibration of the single-degree-of-freedom vibration system in a stable state, and acquiring the damping ratio of the optimal vibration absorber and the natural frequency of the optimal vibration absorber.

6. The vibration reduction method of the magnetic rail vibration absorber according to claim 5, wherein the first step comprises:

using formulas

Acquiring a vibration equation of a two-degree-of-freedom double-damping vibration system under the action of an excitation force of a motor; wherein M represents the mass of the motor, M represents the mass of the mass block, K represents the elastic coefficient of the motor, K represents the elastic coefficient of the mass block, C₁Representing the damping coefficient of the motor, C₂Representing the damping coefficient, x, of the mass₁Representing the displacement of the motor, x₂Represents the displacement of the mass, and p (t) represents the excitation force.

7. The vibration reduction method of the magnetic guide rail vibration absorber according to claim 5, wherein the second step comprises:

if the exciting force of the motor is simple harmonic force, the vibration equation of the two-freedom double-damping vibration system is transformed, and the complex equation of the forced vibration in a stable state is obtained as

Where ω denotes the excitation frequency, i denotes the complex imaginary unit, X₁A complex variable, X, representing the displacement of the motor₂Expressing the complex variable of the displacement of the mass block, P expressing the complex variable of the exciting force, and solving the complex equation to obtain

By the formula

Acquiring the force of the mass block acting on the upper surface of the motor, wherein F₁Representing the force of the mass on the upper surface of the motor.

8. The vibration reduction method of the magnetic guide rail vibration absorber according to claim 5, wherein the third step comprises:

by the formula X₁₀＝P/(K-Mω²+iωC₁) Obtaining a complex solution of the vibration of the single-degree-of-freedom vibration system in a stable state;

by the formula F₁₀＝(K+iωC₁)P/(K-Mω²+iωC₁) Obtaining the force of the motor itself, wherein F₁₀Representing the force of the motor itself;

by the formula

Obtaining a relation between the vibration absorption performance and the frequency of the exciting force, wherein,

xi represents the vibration absorption coefficient, E₁Representing the vibration energy of the mass after acting on the motor, E₁₀Representing the vibration energy of the motor itself, V₁A complex variable, V, representing the speed of vibration of the mass after it has acted on the motor₁₀A complex variable representing the vibration speed of the motor itself;

by means of the strongest frequency equation of complex variable of vibration speed of motor

Selecting parameters of the vibration absorber to make xi>0, wherein ω_rThe strongest frequency of the complex variable of the vibration speed of the motor itself.

9. The vibration damping method for a magnetic guide rail vibration absorber according to claim 5, wherein said step four comprises:

order to

Wherein β represents an amplification factor and

wherein, ω is_nRepresenting the natural frequency of the motor, mu representing the ratio of the mass to the mass of the motor, omega₀Showing the natural frequency, ζ, of the vibration absorber₁Represents the damping ratio of the motor and

ζ₂represents the damping ratio of the vibration absorber and

the amplification factor is adjusted to ensure that the displacement of the motor under the action of the exciting force is minimum in a full frequency band, namely the complex solution of the vibration of the single-degree-of-freedom vibration system in a stable state is minimum.

10. The vibration damping method for the magnetic rail vibration absorber according to claim 9, wherein the process of adjusting the amplification factor comprises:

step 401: taking a frequency band gamma in the neighborhood of the natural frequency of the motor_a≤ω₁≤γ_bWherein γ is_a＝0.7ω_n，γ_b＝1.3ω_n；

Step 402: substituting the initial value of the natural frequency of the vibration absorber and the initial value of the damping ratio of the vibration absorber into a calculation formula of the amplification factor to calculate the value of the amplification factor in the frequency band;

step 403: updating the natural frequency of the vibration absorber and the damping ratio of the vibration absorber, taking the updated natural frequency of the vibration absorber as the initial value of the natural frequency of the vibration absorber, taking the updated damping ratio of the vibration absorber as the initial value of the damping ratio of the vibration absorber, returning to the step 402 until the minimum value of the amplification factor is obtained, taking the damping ratio of the vibration absorber at the moment as the damping ratio of the optimal vibration absorber, and taking the natural frequency of the vibration absorber at the moment as the natural frequency of the optimal vibration absorber.

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