CN101191753A - One disc flexible rotor transient equilibration process - Google Patents

Abstract

The invention relates to a transient balance method for one-disc flexible rotors. The invention is characterized in that: the vibration displacement signals along X direction and Y direction and the corresponding key-phase signals during the acceleration of the rotor are collected; the collected vibration displacement signals are processed, the deflection response, the speed signals along X direction and Y direction, the self-rotation angle acceleration of the rotor, the precession angle of the rotor as well as the speed of the precession angle are obtained, the speed of the precession angle of the rotor is partitioned, and the azimuth angle where the rotor is unbalanced is confirmed according to the result of the partitioning; the magnitude of the unbalanced quantity of the rotor is confirmed by adding one time trial weight; the balance weight is adjusted according to the confirmed azimuth angle and magtitude of the unbalanced quantity of the rotor, to finish the balancing work of the one-disc flexible rotor. With the method provided by the invention, the balancing of the one-disc flexible rotor can be conveniently and quickly realized by transient response; the needed startup times during the balancing is less and the balancing accuracy is high.

Description

One disc flexible rotor transient equilibration process

Technical field

The present invention relates to a kind of one disc flexible rotor transient equilibration process, be mainly used in the equilibrium problem of the rotor that solves high-power, high rotating speed, slender axles.

Background technology

Current, under the trend that directions such as high-power, high rotating speed, slender axles develop, it is outstanding and important more that the equilibrium problem of rotor becomes at rotating machinery.Be divided into modal balancing method that existing balance method is total and influence coefficient method two classes, but because the characteristics of itself structure of single-deck rotor, balance at it has proposed some unique methods, and two-point method, three point method are simply arranged, and the examination that has of more complicated adds weight Zhou Yifa.Two-point method and three point method all are position and the sizes of utilizing graphing method to obtain should to add counterweight, but they all need the machine that opens 3 times at least.Though examination adds weight Zhou Yifa balance quality comparatively speaking than higher, its machine that opens number of times that needs is more, and formality is miscellaneous, and spended time is long.Moreover actual rotor is impossible extraordinaryly be stabilized in work under one or more rotating speeds, in order to overcome this point, just needs to adopt the method for transient equilibrium to come balancing rotor, makes rotor carry out balance under the condition of more realistic work.Therefore study a kind of few transient equilibrium method of machine number of times particular importance that just seems that opens.

Summary of the invention

The technical matters that solves

For fear of the deficiencies in the prior art part, the present invention proposes a kind of one disc flexible rotor transient equilibration process, a kind of few one disc flexible rotor transient equilibration process of machine number of times that opens.

Technical scheme

Technical characterictic of the present invention is:

A) by the vibration displacement sensor and the key signal sensor of two orthogonal installations, gather vibration displacement delta data and corresponding key signal in the rotor accelerator, the data sequence that collects is designated as x (t), y (t) and p (t) respectively;

B) the vibration displacement signal that collects is handled, is tried to achieve: amount of deflection response signal r (t), x, y to rate signal With

, the angle of rotation acceleration a of rotor, the spin velocity of rotor

, rotor angle of precession ψ (t) and angular velocity of precession

C) angular velocity of precession to rotor carries out subregion: with dynamic deflection r (t), the angular velocity of precession of rotor

Spin velocity With key signal p (t) over time figure be superimposed, and with the angular velocity of precession of rotor

Carry out subregion;

I. first district: scope equals the critical rotary speed of rotor to the value of angular velocity of precession from the initial value of angular velocity of precession;

Ii. second district: scope occurs minimum value from the critical rotary speed that angular velocity of precession equals rotor to angular velocity of precession;

Iii. the 3rd district: scope is that the later zone of minimum value appears in angular velocity of precession;

D), determine the position angle at rotor unbalance place according to the result of subregion:

The pairing moment of each minimal value of dynamic deflection r (t) fluctuation is designated as t, and the angle of precession that t is corresponding constantly is designated as ψ (t), and the pairing moment of key signal pulse that t is close to constantly previously is designated as t ₀, can draw following conclusion by analyzing:

I. in the pairing time period of angular velocity of precession second district, the position angle of amount of unbalance can be expressed as on the dish:

$\mathrm{\α}=\frac{1}{2}{\mathrm{at}}^2-\frac{1}{2}{\mathrm{at}}_0^2-\mathrm{\ψ}\left(t\right);$

Ii. in the pairing time period of angular velocity of precession the 3rd district, the position angle of amount of unbalance can be expressed as on the dish:

$\mathrm{\α}=\frac{1}{2}{\mathrm{at}}^2-\frac{1}{2}{\mathrm{at}}_0^2-\mathrm{\ψ}\left(t\right)\±\mathrm{\π};$

E) determine the size of rotor unbalance value: according to the value of the eccentric azimuth angle alpha of the rotor of having determined, on the direction at eccentric place or its opposite direction, add test mass one time, utilize the amplitude of rotor bow response and the linear relationship between the eccentric size $\frac{r_1}{{\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="A20061010495000111.png"\; state="\{\{state\}\}">U</figure-callout>}}_1}=\frac{r_1}{{\mathrm{<figure-callout\; id="2"\; label="U"\; filenames="A20061010495000103.png,A20061010495000111.png"\; state="\{\{state\}\}">U</figure-callout>}}_2}$ Can determine the size of rotor unbalance value; U ₁, r ₁Be respectively rotor initial unbalance, size and the rotor amount of deflection response amplitude under initial unbalance,, U ₂, r ₂Be respectively the amplitude that adds behind test mass amount of unbalance size on the rotor and corresponding rotor bow response;

F),, finish the balance work of single-deck flex rotor by the plus-minus counterweight according to the position angle of the rotor unbalance value of having determined and the size of amount of unbalance.

Described dynamic deflection signal r (t) by $r\left(t\right)=\sqrt{{\left(x\left(t\right)\right)}^2+{\left(y\left(t\right)\right)}^2}$ Determine.

Described x, y to rate signal

With

For: $\stackrel{\&CenterDot;}{x}\left(t\right)=\frac{x(t+1)-x\left(t\right)}{\mathrm{\&Delta;t}}=[x(t+1)-x\left(t\right)]\&CenterDot;f_s$

$\stackrel{\&CenterDot;}{y}\left(t\right)=\frac{y(t+1)-y\left(t\right)}{\mathrm{\&Delta;t}}=[y(t+1)-y\left(t\right)]\&CenterDot;f_s$

Wherein Δ t is the sampling period, f _sBe sample frequency.

The angle of rotation acceleration a of described rotor determines: in the uniformly accelerated motion process, be respectively t by two used times of continuous equal displacement S ₁And t ₂, then the acceleration of this uniformly accelerated motion can be expressed as: $a_0=\frac{2S(t_1-t_2)}{t_1{t}_2({\mathrm{<figure-callout\; id="1"\; label="t"\; filenames="A20061010495000111.png"\; state="\{\{state\}\}">t</figure-callout>}}_1+t_2)},$ Get S=2 π rad, t ₁Be time period, the t between the two adjacent key signals ₂For following t closely ₁Time period between the two adjacent key signals afterwards, between different key signals, can calculate a plurality of a ₀Value is then with these a ₀Value averages, and just can obtain the final angular acceleration a of rotor.

The spin velocity of described rotor

For: $\stackrel{\&CenterDot;}{\mathrm{\&phi;}}\left(t\right)=\frac{1}{2}{\mathrm{at}}^2.$

The angle of precession ψ (t) of described rotor is: $\mathrm{\&psi;}\left(t\right)=\arctan \left(\frac{y\left(t\right)}{x\left(t\right)}\right)+\mathrm{n\&pi;},$ (n=0,1 ...), and the value of n should guarantee to calculate angle of precession ψ (t) can not occur the sudden change.

Described angular velocity of precession

For: $\stackrel{\&CenterDot;}{\mathrm{\&psi;}}\left(t\right)=\frac{\stackrel{\&CenterDot;}{y}\left(t\right)x\left(t\right)-\stackrel{\&CenterDot;}{x}\left(t\right)y\left(y\right)}{x^2\left(t\right)+y^2\left(t\right)}.$

Beneficial effect

The way of utilizing the present invention to propose can realize the balance of single-deck flex rotor quickly and easily by transient response, and the machine that the opens number of times that needs in the equilibrium process is few, the balance quality height.

Description of drawings

Fig. 1: RK4 rotor experiment table synoptic diagram

Fig. 2: the feature dish of RK4 rotor experiment table

Fig. 3: the x of feature dish, y are to displacement response figure in the accelerator

Fig. 4: the stack of response diagram in the rotor accelerator

Embodiment

Now in conjunction with the accompanying drawings the present invention is further described:

Present embodiment is to finish on the RK4 of Bently company rotor experiment table (with reference to figure 1).The feature dish of rotor is the steel disk (with reference to figure 2) with the equal thickness in 16 holes, and each center, hole all is 3cm to the distance of armature spindle.16 holes are used for setting the initial unbalance of rotor on the one hand, are used for adding when balancing rotor test mass on the other hand.Rotor-support-foundation system is supporting the mass screw that a plurality of weight do not wait such as has from 0.1g to 2g.

The parameters of rotor-support-foundation system is as follows:

The total length l=0.56m of axle, l is respectively stretched out at the bearing seat two ends ₁=l ₂=0.03m, the diameter d=10mm of axle, the density of axle is ρ=7.8 * 10 ³Kg/m ³, the quality of dish is m=0.8kg, diameter D=75mm.The maximum speed of this rotor-support-foundation system can reach 10000rpm, and its critical rotary speed is 1680rpm.

Carry out the balance of single-deck flex rotor:

Collect the feature dish x of place, y to vibration displacement signal x (t), y (t) (as shown in Figure 3) and key signal p (t).

Wherein p (t) is a series of pulse signals.

Dynamic deflection r (t), angular velocity of precession with rotor

Spin velocity With key signal p (t) over time figure be superimposed, and with the angular velocity of precession of rotor

Carry out subregion (as shown in Figure 4)

According to a that asks that is proposed in this transient equilibrium method ₀Method, calculate in the present embodiment 20 different a ₀Value, as shown in table 1, then to all a ₀Average, can obtain the actual rotary acceleration a=46.360rad/s of rotor ²

Table 1 calculates a of gained ₀(rad/s ²) value

46.392	46.320	46.358	46.346	46.386	46.373	46.342	46.300	46.379	46.341
										46.359	46.376	46.390	46.371	46.315	46.334	46.391	46.389	46.338	46.387

The big or small result who determines the position angle of rotor unbalance value and amount of unbalance is respectively shown in table 2 and table 3:

The azimuthal recognition result of table 2 amount of unbalance

Actual value (rad)	π/4	π/2	5π/8	3π/4	5π/4	3π/2	13π/8	7π/4
									Recognition result (rad)	0.865	1.691	1.800	2.530	4.139	4.948	5.234	5.623
Relative error ε	10.14％	7.65％	8.33％	7.38％	5.40％	5.01％	2.53％	2.28％

The recognition result of table 3 amount of unbalance size

The size (gcm) that adds test mass	0.3	0.6	1.2	-2.4	-3.0	-3.6	4.8	6.0
									Add the amount of unbalance (gcm) that draws behind test mass	0.3196	0.6286	0.6077	1.1740	2.380	2.968	-6.0	-4.8
Actual amount of unbalance (gcm)	0.3	0.6	0.6	1.2	2.4	3.0	4.6195	5.9082
									Relative error ε (%)	6.53％	4.77％	1.28％	2.17％	0.83％	1.07％	3.76％	1.53％

Some performance of relative error in the table 2 is bigger, but its corresponding absolute error maximum is no more than 10 °, illustrates that azimuthal identification is more accurate to imbalance.Add adding an examination of of test mass in the table 3 and focus on the eccentric orientation of amount of unbalance on the occasion of expression institute, and negative value represent add an examination of and focus on the opposite direction in amount of unbalance off-centre orientation.

Each step of front has been identified the position angle of rotor unbalance value and the size of amount of unbalance, adds an equal-sized counterweight then on the opposite direction at amount of unbalance place, can finish the balance of this single-deck rotor.

Claims (7)

1. one disc flexible rotor transient equilibration process is characterized in that:

A) by the vibration displacement sensor and the key signal sensor of two orthogonal installations, gather vibration displacement delta data and corresponding key signal in the rotor accelerator, the data sequence that collects is designated as x (t), y (t) and p (t) respectively;

B) the vibration displacement signal that collects is handled, is tried to achieve: amount of deflection response signal r (t), x, y to rate signal

With

The angle of rotation acceleration a of rotor, the spin velocity of rotor The angle of precession ψ (t) and the angular velocity of precession of rotor

C) angular velocity of precession to rotor carries out subregion: with dynamic deflection r (t), the angular velocity of precession of rotor

Spin velocity

With key signal p (t) over time figure be superimposed, and with the angular velocity of precession of rotor

Carry out subregion;

I. first district: scope equals the critical rotary speed of rotor to the value of angular velocity of precession from the initial value of angular velocity of precession;

Ii. second district: scope occurs minimum value from the critical rotary speed that angular velocity of precession equals rotor to angular velocity of precession;

Iii. the 3rd district: scope is that the later zone of minimum value appears in angular velocity of precession;

D), determine the position angle at rotor unbalance place according to the result of subregion:

The pairing moment of each minimal value of dynamic deflection r (t) fluctuation is designated as t, and the angle of precession that t is corresponding constantly is designated as ψ (t), and the pairing moment of key signal pulse that t is close to constantly previously is designated as t ₀, can draw following conclusion by analyzing:

I. in the pairing time period of angular velocity of precession second district, the position angle of amount of unbalance can be expressed as on the dish:

$\mathrm{\&alpha;}=\frac{1}{2}a{t}^2-\frac{1}{2}a{t}_0^2-\mathrm{\&psi;}\left(t\right);$

Ii. in the pairing time period of angular velocity of precession the 3rd district, the position angle of amount of unbalance can be expressed as on the dish:

$\mathrm{\&alpha;}=\frac{1}{2}a{t}^2-\frac{1}{2}a{t}_0^2-\mathrm{\&psi;}\left(t\right)\&PlusMinus;\mathrm{\&pi;};$

E) determine the size of rotor unbalance value: according to the value of the eccentric azimuth angle alpha of the rotor of having determined, on the direction at eccentric place or its opposite direction, add test mass one time, utilize the amplitude of rotor bow response and the linear relationship between the eccentric size $\frac{r_1}{U_1}=\frac{r_2}{U_2}$ Can determine the size of rotor unbalance value; U ₁, r ₁Be respectively rotor

Initial unbalance, size and the rotor amount of deflection response amplitude under initial unbalance,, U ₂, r ₂Be respectively the amplitude that adds behind test mass amount of unbalance size on the rotor and corresponding rotor bow response;

F),, finish the balance work of single-deck flex rotor by the plus-minus counterweight according to the position angle of the rotor unbalance value of having determined and the size of amount of unbalance.

2. one disc flexible rotor transient equilibration process according to claim 1 is characterized in that: described dynamic deflection signal r (t) by $r\left(t\right)=\sqrt{{\left(x\left(t\right)\right)}^2+{\left(y\left(t\right)\right)}^2}$ Determine.

3. one disc flexible rotor transient equilibration process according to claim 1 is characterized in that: described x, y to rate signal

With For: $\stackrel{\&CenterDot;}{x}\left(t\right)=\frac{x(t+1)-x\left(t\right)}{\mathrm{\&Delta;t}}=[x(t+1)-x\left(t\right)]\&CenterDot;f_s$

$\stackrel{\&CenterDot;}{y}\left(t\right)=\frac{y(t+1)-y\left(t\right)}{\mathrm{\&Delta;t}}=[y(t+1)-y\left(t\right)]\&CenterDot;f_s$

Wherein Δ t is the sampling period, f _sBe sample frequency.

4. one disc flexible rotor transient equilibration process according to claim 1 is characterized in that: the angle of rotation acceleration a of described rotor determines: in the uniformly accelerated motion process, be respectively t by two used times of continuous equal displacement s ₁And t ₂, then the acceleration of this uniformly accelerated motion can be expressed as: $a_0=\frac{2S(t_1-t_2)}{t_1{t}_2(t_1+t_2)},$ Get S=2 π rad, t ₁Be time period, the t between the two adjacent key signals ₂For following t closely ₁Time period between the two adjacent key signals afterwards, between different key signals, can calculate a plurality of a ₀Value is then with these a ₀Value averages, and just can obtain the final angular acceleration a of rotor.

5. one disc flexible rotor transient equilibration process according to claim 1 is characterized in that: the spin velocity of described rotor

For: $\stackrel{\&CenterDot;}{\mathrm{\&phi;}}\left(t\right)=\frac{1}{2}a{t}^2.$

6. one disc flexible rotor transient equilibration process according to claim 1 is characterized in that: the angle of precession ψ (t) of described rotor is: $\mathrm{\&psi;}\left(t\right)=\arctan \left(\frac{y\left(t\right)}{x\left(t\right)}\right)+\mathrm{n\&pi;},(n=\mathrm{0,1},...),$ And the value of n should guarantee to calculate angle of precession ψ (t) can not occur the sudden change.

7. one disc flexible rotor transient equilibration process according to claim 1 is characterized in that: described angular velocity of precession

For: $\stackrel{\&CenterDot;}{\mathrm{\&psi;}}\left(t\right)=\frac{\stackrel{\&CenterDot;}{y}\left(t\right)x\left(t\right)-\stackrel{\&CenterDot;}{x}\left(t\right)y\left(t\right)}{x^2\left(t\right)+y^2\left(t\right)}.$

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