JPH0633636A - Damping device - Google Patents

Abstract

PURPOSE:To perform calculation of a control amount for a dynamic vibration absorber by estimating the vibration mode of a structure in a shorter time. CONSTITUTION:Sensors 15a and 15b for detecting displacement are mounted to two spots of the first floor and the roof 2a of a building 2. A CPU 25 of a control device 4 counts the vibration frequency of the building 2 by means of output signals from the sensors 15a and 15b and based on an integrated value, a vibration mode is estimated. A control amount (u) on a dynamic vibration absorber 3 is computed from displacement of the roof 2a of the building 2 determined by an output difference between the sensors 15a and 15b and a constant responding to a vibration mode.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damping device, and more particularly to a vibration damping device configured to displace vibration of a structure by displacing an additional mass.

[0002]

2. Description of the Related Art For example, a structure such as a building is provided with a vibration damping device for damping vibrations caused by an earthquake or wind pressure. In this type of vibration damping device, a dynamic vibration absorber displaces an additional mass having a predetermined weight mainly depending on the mass of the building in accordance with the vibration state of the building to suppress the vibration of the building. .

As a conventional vibration damping device, for example, an additional mass is slidably supported by a linear bearing or the like, and a transmission mechanism such as a ball screw screwed to the additional mass is driven by a motor or the like so that the additional mass is horizontal. Devices having a dynamic vibration absorber configured to be reciprocally moved in a direction are contemplated.

The dynamic vibration absorber drives and controls the motor by a drive signal from a control device which calculates a control amount according to the displacement and speed of the building, and moves the additional mass.

[0005]

In the above control device, since the displacement of the building is detected by the sensor and the control amount of the dynamic vibration absorber according to the displacement is obtained, for example, in the case of a high-rise building with 30 floors or more, It was necessary to provide a sensor for each floor to detect the displacement of each floor and to perform a complex equation of motion calculation based on the output of each sensor to analyze the vibration mode of the building.

Moreover, since it takes a lot of time and equipment to install a sensor on each floor of a high-rise building, it is considered to reduce the number of sensors. Further, when installing a vibration damping device in a building that has already been constructed, it is difficult to install a sensor on each floor, and for example, a sensor is often installed on every 4th to 5th floors.

In this case, since the number of sensors is smaller than the number of floors of the building, the solution of the differential equation relating to the mathematical model of the building is obtained to estimate the displacement of each floor.

However, in order to calculate the displacement of each floor on the basis of the output from the sensor to obtain the control amount of the dynamic vibration absorber, the calculation amount in the control device becomes remarkably large and the calculation time becomes long. .

Moreover, since the output from the control device to the dynamic vibration absorber is delayed with respect to the output from the sensor, not only the response of the control operation of the dynamic vibration absorber is deteriorated, but conversely, the building is vibrated by the dynamic vibration absorber. There is a problem such as doing.

Therefore, an object of the present invention is to provide a vibration damping device that solves the above problems.

[0011]

DISCLOSURE OF THE INVENTION The present invention provides a dynamic vibration reducer for driving a mass so as to suppress vibration of a multilayer structure, and at least a lower layer portion of the structure and an upper layer portion of the structure. A sensor that is provided and detects the displacement of each installation part,
Frequency calculating means for calculating the vibration frequency of the upper layer portion with respect to the lower layer portion based on the output of each sensor, and determining means for determining the vibration mode of the structure based on the vibration frequency obtained by the frequency calculating means; And a control amount calculation unit that calculates a control amount of the dynamic vibration reducer according to the vibration mode determined by the determination unit.

[0012]

Since the vibration mode of the structure can be estimated if at least the upper layer portion and the lower layer portion of the structure have sensors, the number of sensors can be reduced to perform the vibration damping operation and the calculation time can be shortened, and the dynamic vibration absorber can be reduced. It is possible to improve the responsiveness of the vibration damping operation.

[0013]

1 to 4 show an embodiment of a vibration damping device according to the present invention.

In each figure, the vibration damping device 1 is a horizontal structure of the building 2 in which the dynamic vibration absorber 3 installed on the roof 2a of the building 2 as a structure performs a vibration damping operation according to a control signal from the control device 4. Controls directional vibration.

The dynamic vibration reducer 3 is a building 2 as shown in FIGS.
The additional mass 6 slides in the X direction on the base 5 installed on the roof 2a of the building 2. The additional mass 6 has a mass of about 0.5% with respect to the total mass of the building 2, for example, It has a weight of about 5-10 tons. Therefore, the additional mass 6 is slidably supported by the linear bearing 7 on the base 5.

An AC servomotor (hereinafter referred to as a motor) 8 as an actuator and an electromagnetic brake 9 are provided on the base 5, and an output shaft 8a of the motor 8 has a bearing 11 via a coupling 10. , 12 are coupled to a ball screw 13 which is rotatably supported. The ball screw 13 is screwed into the additional mass 6 and penetrates it. Therefore, the additional mass 6 moves in the recess 5 a of the base 5 by the rotation of the ball screw 13.

When the building 2 vibrates due to wind pressure or an earthquake,
As will be described later, the control device 4 calculates a control amount according to the magnitude of vibration and outputs a drive signal to the motor 8 of the dynamic vibration reducer 3. The motor 8 rotates the ball screw 13 by supplying the drive signal to move the additional mass 6 in the X direction (vibration direction). At this time, the reaction of the generated inertial force of the additional mass 6 suppresses the vibration of the building 2.

The electromagnetic brake 9 is in the off state in the vibration damping mode, and brakes the ball screw 13 in the stop mode in which the power is turned off.

Sensors 15a and 15b for detecting displacement and speed due to vibration of the building 2 are installed on the lower and upper layers of the building 2, for example, the floor of the first floor and the roof 2a.

On the roof 2a of the 30-story building 2,
An anemometer 16 for measuring the wind speed (V) is installed, and the dynamic vibration absorber 3 is provided with a sensor 18 for detecting the displacement, speed and acceleration of the additional mass 6. The detection signals from the sensors 15a, 15b and the sensor 18 are servo amplifiers 19a-1.
It is amplified by 9c and input to the subtraction circuit 20. In the subtraction circuit 20, the roof 2a is based on the displacement and speed of the first floor.
Calculate the actual displacement and velocity of. That is, the subtraction circuit 20 subtracts the displacement and the speed detected by the sensor 15a on the first floor from the displacement and the speed detected by the sensor 15b on the roof 2a to make the vibration of the roof 2a when the vibration on the first floor becomes zero. Calculate the size.

The detection signal from the anemometer 16 is sent to the amplifier 2
The signal is amplified by 1 and input to the control device 4.

Reference numeral 22 is a seismometer, which is buried in the ground so as to detect seismic waves propagating on the ground. When an earthquake occurs, the detection signal from the seismograph 22 is amplified by the amplifier 23 and input to the control device 4.

The control device 4 has an A / D converter 24 as an input unit, a CPU 25 for calculating the control amount to the dynamic vibration absorber 3, a D / A converter 26 as an output unit, and an I / O interface circuit 27. . The A / D converter 24 is a switch 28
It is connected to the subtraction circuit 20 via the, and converts the detection signal from each sensor into a digital signal and outputs it to the CPU 25.

As will be described later, the CPU 25 calculates the control amount of the dynamic vibration reducer 3 based on each signal from the A / D converter 24 and the I / O interface circuit 27, and outputs it to the D / A converter 26. Further, the digital signal of the control amount output from the D / A converter 26 is input to the servo driver 29, and the servo driver 29 drives the torque command current as the drive signal according to the control amount calculated by the CPU 25. Output to the motor 8 of the vibration absorber 3.

Reference numeral 30 denotes a memory, which stores each program for damping control, and also stores initial values and the like of each calculation required for damping control. For example, in the memory 30, as shown in FIG.
Vibration frequency calculation program 30A executed by PU25,
Each program such as the vibration mode determination program 30B and the control amount calculation program 30C is stored.

A power source 31 is connected to the control device 4 and the servo driver 29, and an emergency stop switch 32 is arranged between the power source 31 and the servo driver 29. This switch 32 has a normally-closed contact, and for example, when an excessive earthquake occurs, the I / O interface circuit 27
It is excited by the stop signal from and opens.

Reference numeral 34 is an indicator, and when there is an abnormality in the control system of the dynamic vibration absorber 3 or each sensor 15a, 15b, 18, the anemometer 16, the seismograph 22, etc., the details of the abnormality are displayed and displayed to the observer. Inform.

Reference numeral 35 is an alarm device which issues an alarm when an abnormality occurs.

Next, the processing executed by the CPU 25 of the control device 4 when the vibration damping device 1 performs the vibration damping operation will be described with reference to FIG.
Will be described with reference to.

The CPU 25 executes the processing of FIG. 5 every 5 msec, for example.

In the control device 4, initial settings for performing arithmetic processing are performed in advance. As the initial value to be set, for example, the frequency of the vibration mode of the building 2 (in this embodiment, the vibration frequency of the primary mode is 0.5 Hz, the vibration frequency of the secondary mode is 1.5 Hz, and the vibration frequency of the tertiary mode is 6 Hz) and the amplitude magnifications P ₁ , P ₂ , P _{3 and the} like for each vibration mode, which are stored in the memory 30, respectively.

Here, before explaining the process shown in FIG. 5, the vibration mode discrimination method performed by the control device 4, that is, the building 2
A method of estimating the vibration state of the entire building 2 based on the output signals from the sensors 15a and 15b provided on the first floor and the roof 2a will be described.

First, consider the building 2 and the dynamic vibration reducer 3 by replacing them with a dynamic model as shown in FIG. If the building 2 is n story, and n pieces of the mass (m _s1 ~m _sn), and n number of springs connecting between each floor (the spring constant K _s1 ~K _sn), damping elements between each floor (viscous damping The dynamic model is composed of the coefficients C _{s1 to} C _sn ). The dynamic vibration absorber 3 provided on the roof 2a of the building 2 is modeled as a mass ma and a control amount u.

In this embodiment, the model shown in FIG. 6 is used.
Displacement X of each mass estimated by₁~ X _nTo #X₁~ #X_n
Will be expressed as Also, the estimated velocity of each mass is #X
₁'~ # X_n', And hereinafter, each estimated value is attached with #
To do. However, Xi is the absolute displacement on each floor from the absolute displacement Yi
The displacement Z is subtracted (Xi = Yi−Z).

Here, the state displacement vector will be referred to as << X >>, and the vector will be enclosed in <<>>. Then, an estimate of the state displacement vector, "#X" = [# Xa, # Xa ', # X 1, # X 2 ... # X
_{n, # X 1 ', #} X 2', ... #X n ' ] when ^{T, the} equation of state, "#X'becomes" = "A"#X'+"B" u ... (1) . Here, the Xa is a relative displacement between the dynamic vibration reducer 3 and the building 2.

However, in the above (1),

[0037]

[Equation 1]

[0038]

Next, in the above model, the evaluation function J is set so as to minimize the displacement X of the building 2 while considering the constraint condition of the dynamic vibration absorber 3.

[0040]

[Equation 2]

The feedback gain << F >> is determined so as to satisfy this condition.

The control amount u to the dynamic vibration reducer 3 can be expressed as u =-<< F >><<# X >> by multiplying the feedback gain << F >> by the displacement << X >>.

Further, the feedback gain << F >> is expressed as ^<< F >> = R ^{-1 <<} B >> ^T << P >>.

The matrix << P >> is the Riccati equation << A >> ^T << P >> + << P >><< A >> + << Q >>-<< P >><< B >>
The solution is R ^{-1 <<} B >> ^T << P >> = 0.

Therefore, the control amount u output to the motor 8 for driving the additional mass 6 of the dynamic vibration reducer 3 is u =-<< F >><<# X >> (8) in the above dynamic model.

In the present invention, the displacement of each floor of the building 2 is estimated as follows.

In the high-rise building 2, FIG. 7 (A)
As shown in (B) and (C), the vibration modes of the building 2 can be broadly divided into primary, secondary, and tertiary modes. Therefore, the vibration mode of the building 2 is determined based on the displacement of the roof 2a having the largest displacement of the building 2. I will decide.

That is, the displacement of the roof 2a of the building 2 becomes a slow speed in the first mode and the second mode, the third mode.
The speed increases as the mode changes to the next mode, and the vibration frequency increases as the mode changes from the primary mode to the tertiary mode. Therefore, the vibration mode of the building 2 is determined by detecting the vibration frequency of the roof 2a from the output of the sensor 15b provided on the roof 2a of the building 2. Then, in advance, the amplitude magnification P ₁ of each vibration mode in the dynamic model of the building 2 (shown in FIG. 6),
P ₂ and P ₃ are obtained by simulation, and the memory 30
To remember.

For example, when an earthquake propagates to the building 2, the displacement of the roof 2a (output of the sensor 15b) has a waveform of physical coordinates as shown in FIG. When the waveform shown in FIG. 8 is converted into a waveform of mode coordinates, it is represented by a diagram of amplitude magnification and frequency as shown in FIG.

From FIG. 9, the frequency of the primary mode is 0.5 Hz,
It can be seen that the frequency of the secondary mode is 1.5 Hz and the frequency of the tertiary mode is 6 Hz.

In the first-order mode, the mass of each floor m
The estimated displacement #X _{i of si} can be expressed as #X _i = αi (sin ω ₁ t + φ ₁ ) ... (9). However, αi is an amplitude magnification for each floor obtained by simulation.

Therefore, the displacements of the respective floors can be obtained from the above equation (9) based on the outputs from the sensors 15a and 15b.

The estimated displacement #X _{i of} each floor can be expressed as #X _i = α _1i 'Xn (10) only by the displacement Xn of the roof 2a, that is, from the output difference between the sensors 15a and 15b.

Also in the secondary mode, the estimated displacement #X _{i of} each floor can be expressed as follows: #X _i = α _2i (sin ω ₂ t + φ _2i ) ... (11) Then, the phase φ ₂₀ ~φ ₂₁ ~─~
If φ _2n , then it can be expressed as #X _i = α _2i 'Xn (12).

Also in the third mode, the estimated displacement #X _{i of} each floor can be approximated as follows: #X _i = α _3i 'Xn (13)

Therefore, the control unit 4 determines the vibration mode based on the vibration frequency of the building 2, and then selects the amplitude magnifications P ₁ , P ₂ and P ₃ according to the vibration mode to calculate the control amount u. Output to the dynamic vibration reducer 3.

In FIG. 5, the CPU 25 of the control device 4 performs an abnormality check of the vibration damping system in step S1 (the following steps will be omitted). For example, it is checked whether or not the control system of the dynamic vibration absorber 3 and each detecting means such as the sensors 15a, 15b and 18, the seismograph 22, the anemometer 16 have an abnormality. If there is no abnormality in S2, the operation proceeds to S3. The detection signal from each detecting means is read.

That is, in S3, the first floor of the building 2 and the roof 2a
Then, the displacement vector << X >> is obtained by reading the displacement of the additional mass 6 of the dynamic vibration absorber 3 and the velocities X ₁ (K), X _n (K), Xa (k) and Xa (k) ′ of the additional mass 6.

In the next step S4, it is checked whether or not the roof 2a of the building 2 vibrates in the horizontal direction, is displaced from the − direction to the + direction, and passes through the zero point. Therefore, in S4, the read value X _n (k-
1) is multiplied by the read value X _n (K) of this time, and the roof 2a
Has a positive value when the center point of has not passed the zero point, and has a negative value when the center point of the rooftop 2a has passed the zero point.

Therefore, when the multiplication value is positive in S4, the process proceeds to S5 and the frequency counter value is incremented by 1. Next S
At 6, the displacement << X >> is obtained from the amplitude magnification << P >> selected by the frequency counter value. Then, in S7, the controlled variable u is calculated based on the above equation (8), and in S8, the controlled variable u is output to the dynamic vibration absorber 3.

In this case, since the center point of the roof 2a of the building 2 does not pass the zero point, the displacement << X >> is calculated based on the same amplitude magnification Pi as the previous time, and the control amount u is calculated.

When the building 2 is not displaced, the roof 2
Since the displacement of a is zero, the controlled variable u becomes zero in S7,
The dynamic vibration reducer 3 does not perform the vibration damping operation.

In S4, if the multiplication value is negative,
In S9, it is checked whether the integrated value of the frequency counter is 190 or more. The integrated value 190 is the number of calculations from the time when the central point of the rooftop 2a passes through the zero point to the time when it returns to the zero point. Since the cycle is long when the vibration is in the primary mode, the integrated value is also large. Become.

That is, when the frequency of the primary mode is 0.5 Hz, the natural period of sampling is 0.005 seconds, so that when the vibration of the primary mode occurs, the integrated value of the frequency counter is 2/2 × 0. 0.005 = 200. However, if the error of the counter value is 5%,
The next discrimination value is set to 190.

When the vibration mode of the building 2 is the first-order mode, the frequency counter becomes 190 or more, so that the steps S9 to S9 are performed.
Then, the process proceeds to step 10, and << P ₁ >> which has been inputted in the memory 30 in advance is selected for the amplitude magnification << P >>.

In the next step S11, the frequency counter is reset to zero. After that, S6 and S7 described above are executed, and the control amount u according to the vibration mode estimated by the frequency is calculated and output to the dynamic vibration reducer 3. Then, in the dynamic vibration reducer 3, the motor 8 is driven by the input control amount u to drive the additional mass 6 in the damping direction.

In S9, when the integrated value of the frequency counter is 190 or less, the process proceeds to S12 and it is checked whether the integrated value is 60 or more.

When the frequency of the secondary mode is 1.5 Hz, the natural period is 0.666 seconds. Therefore, when the vibration of the secondary mode occurs, the integrated value of the frequency counter is 0.666.
/ 2 x 0.005 = 66.6. Then, assuming that the error of the counter value is 5%, the secondary discriminant value of the frequency counter is 6%.
Set to 0.

Therefore, when the vibration mode of the building 2 is the secondary mode, the frequency counter becomes 60 or more. That is, when the integrated value of the frequency counter is 60 to 189, it can be estimated that the vibration mode of the building 2 is the secondary mode. Therefore, the integrated value of the frequency counter is 6 in S12.
0 shifts are to S13 above case, S11 by selecting the amplitude ratio "P" is input in advance in the memory 30 to "P _2",
The processing of S6, S7 and S8 is executed.

When the integrated value of the frequency counter is 59 or less in S12, it is estimated that the vibration mode of the building 2 is the third-order mode, the process proceeds to S14, and the amplitude magnification << P >> is previously set for the third-order mode. << P ₃ >> which is set to is selected and the processing of S11, S6, S7 and S8 is executed.

If there is an abnormality in the dynamic vibration reducer 3 or the like in S2, the flow advances to S15 to set the control amount u to the dynamic vibration reducer 3 to zero.

As described above, in this embodiment, the vibration frequency of the building 2 can be counted to estimate the vibration mode,
Since the control amount u to the dynamic vibration reducer 3 can be calculated based on the estimated value, the calculation processing time can be shortened and the vibration damping operation delay of the dynamic vibration reducer 3 can be eliminated.

Moreover, the sensors 15 are provided on the upper and lower parts of the building 2.
Since only a and 15b are provided, the number of sensors is small, and the installation cost of the vibration damping device 1 can be reduced and the installation work can be facilitated even in a high-rise building. In particular, when the vibration damping device 1 is attached to an existing building, the construction period can be shortened, which is advantageous.

Although the sensors 15a and 15b are installed at two places on the first floor and the rooftop 2a of the building 2 of the embodiment, the invention is not limited to this, and the sensors may be provided at two or more places, or other than the first floor. Of course, it may be installed in the lower part of the building or in the upper part of the building other than the rooftop.

[0075]

As described above, the damping device according to the present invention is
If there are sensors in at least the upper and lower layers of the structure, it is possible to estimate the vibration mode of the structure, reduce the number of sensors, simplify the installation work, reduce the installation cost, and reduce the vibration absorber. The control amount of can be calculated in a short time. Therefore, when the structure vibrates, the vibration damping operation of the dynamic vibration absorber is not delayed and the structure is not vibrated, and the response of the vibration damping operation by the dynamic vibration absorber can be improved. .

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of a vibration damping device according to the present invention.

FIG. 2 is a front view of a dynamic vibration reducer.

FIG. 3 is a vertical sectional view of a dynamic vibration reducer.

FIG. 4 is a diagram showing items stored in a memory.

FIG. 5 is a flowchart executed by the CPU of the control device.

FIG. 6 is a diagram showing a dynamic model of a building.

FIG. 7 is a diagram showing vibration modes of a dynamic model.

FIG. 8 is a waveform diagram showing a relationship between an amplitude and a cycle when a building vibrates.

9 is a waveform diagram in which the waveform of FIG. 8 is converted into a relationship between an amplitude magnification and a frequency.

[Explanation of symbols]

 1 Vibration Control Device 2 Building 3 Dynamic Vibration Absorber 4 Control Device 6 Additional Mass 8 AC Servo Motor 15a, 15b, 18 Sensor 16 Anemometer 25 CPU

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuru Kageyama 4-640 Shimoseito, Kiyose-shi, Tokyo Inside Obayashi Institute of Technology Co., Ltd. (72) Inventor Keiko Matsuoka 1-6-3 Fujimi, Kawasaki-ku, Kanagawa Prefecture Tokiko Within the corporation

Claims (1)

[Claims] 1. A dynamic vibration absorber that drives a mass to suppress vibration of a multi-layered structure, and at least a lower layer portion of the structure and an upper layer portion of the structure. A frequency detecting means for calculating the vibration frequency of the upper layer portion with respect to the lower layer portion by the output of each sensor, and the vibration mode of the structure based on the vibration frequency obtained by the frequency calculating means. A vibration damping device comprising: a determining unit for controlling the dynamic vibration absorber and a control amount calculating unit for calculating a control amount of the dynamic vibration reducer according to the vibration mode determined by the determining unit.