JPH05231039A - Vibration control device - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide a vibration damping device that performs vibration damping control adapted to vibrations according to wind pressure and an earthquake. [Constitution] In the control device 4, the detection signal of the displacement of the building 2 at the ground level detected by the sensor 15a is transmitted via the servo amplifier 19a, and the detection signal of the frequency higher than the primary natural frequency of the building 2 is detected by the high pass filter 33. Is entered. As a result of the analysis of the detection signal, if it is determined that the seismic damping device 4 is an excessive large seismic wave that cannot be damped,
Switch 3 to cut off the power supply to the servo driver 29
Open 2. As a result, the additional mass 6 is simultaneously braked by the electromagnetic brake and stopped.

Description

Detailed Description of the Invention

[0001]

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

[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, the vibration generated in the building is damped by operating a dynamic vibration absorber that displaces an additional mass having a predetermined weight mainly depending on the mass of the building according to the vibration state 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 moved in the horizontal direction. Devices having a dynamic vibration absorber configured to be reciprocally moved have been considered.

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

Further, when an excessively large seismic wave having excessive energy that cannot be controlled by the dynamic vibration reducer is generated, if the dynamic vibration reducer is controlled so as to suppress the vibration of the building due to the seismic wave, the result is added. Mass is overdriven. As a result, the additional mass exceeds the range of movement thereof and collides with the stopper, which in turn excites the building. Therefore, the power supply of the dynamic vibration absorber is automatically stopped in response to such an excessive earthquake wave.

[0006]

However, even if a seismic wave having a frequency lower than the primary natural frequency of a building is conventionally used, if the amount of energy of the seismic wave exceeds a predetermined threshold value, the seismic wave moves uniformly. The power supply to the vibration absorber was stopped. However, if the seismic wave is lower than the primary natural frequency of the building, the building only vibrates as a rigid body and the building is hardly deformed. In such a case, the magnitude of the vibration of the building is comparatively small, and the vibration cannot be damped by the dynamic vibration absorber, so that the vibration damping action by the dynamic vibration absorber is not originally performed.

In addition, after the power supply to the dynamic vibration reducer is stopped as described above, a seismic wave having energy higher than the primary natural frequency of the building and within a range in which vibration can be suppressed by the dynamic vibration reducer is applied. However, since the power supply to the dynamic vibration reducer is cut off as described above, the vibration damping operation cannot be performed by the dynamic vibration reducer.

In order to prevent such an adverse effect, it is conceivable to provide the sensor with a band-pass filter as in the configuration disclosed in Japanese Patent Laid-Open No. 3-140647. However, when the sensor is provided with a bandpass filter, the dynamic vibration suppressor operates based on the output signal from the bandpass filter. On the other hand, a signal passing through the bandpass filter has a phase delay due to the bandpass filter, and this phase delay causes a problem that the accuracy of the vibration damping operation is deteriorated.

The present invention has been made in view of the above problems, and provides a vibration damping device that effectively performs a vibration damping operation only when the supply of power to a dynamic vibration absorber due to the occurrence of an excessive earthquake is stopped to a minimum. The purpose is to provide.

[0010]

The invention according to claim 1 is
A vibration damping device for damping a vibration of a structure by generating a driving signal based on a detection signal from a sensor that detects a displacement of a structure and a ground and driving an actuator by the driving signal to move an additional mass. , Inputting the output signal of the sensor through a filter that passes a signal of the frequency of the natural frequency of the structure, and determining that the vibration suppression for displacement of the structure and the ground exceeds the capacity of the vibration damping device. It is characterized in that it has an operation stopping means for stopping the operation of the additional mass at the time.

The invention according to claim 2 is characterized in that the operation stopping means comprises an opening / closing means for stopping the power supply to the drive signal generating means for generating the drive signal. According to a third aspect of the present invention, the filter is a high-pass filter that allows a signal having a frequency equal to or higher than the primary natural frequency of the structure to pass therethrough.

[0012]

According to the first aspect of the invention, since it is determined whether or not the operation of the additional mass is stopped based on the signal of the frequency of the natural frequency of the structure through the filter, the vibration damping device is originally intended. It is suppressed that the operation of the additional mass is stopped by the seismic wave of the frequency that does not perform the vibration suppressing operation.

According to the second aspect of the present invention, the movement of the additional mass is stopped by stopping the power supply of the driving means by the opening / closing means.

According to the third aspect of the present invention, by providing a high-pass filter that allows frequencies higher than the primary natural frequency of the structure to pass therethrough, the additional mass is added by the seismic wave having a frequency at which the damping device does not substantially perform damping operation. Is prevented from being stopped.

[0015]

1 to 3 show an embodiment of a vibration damping device according to the present invention.

In each of the drawings, the vibration damping device 1 is generally a dynamic vibration absorber 3 installed on the roof of a building 2 as a structure, and a control device 4 is provided.
The vibration is controlled by the control signal from the building 2 to suppress the horizontal vibration of the building 2.

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 rooftop 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, 5 It has a weight of about 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. It is connected to a ball screw 13 which is supported by 12. 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, the control device 4 calculates a control amount according to the magnitude of the vibration and outputs a drive signal to the motor 8 of the dynamic vibration absorber 3 as described later. The motor 8 supplies the drive signal to the ball screw 1
3 is rotated to move the additional mass 6 in the X direction (vibration direction). At this time, the vibration of the building 2 is damped by the reaction of the generated inertial force of the additional mass 6.

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

For example, the first floor, the fifth floor, the tenth floor, 15 of the building 2
Sensors 15a to 15d that detect displacement and speed due to vibration of the building 2 are installed on a plurality of floors.

An anemometer 16 for measuring the wind speed (V) is installed on the roof of the 15-story building 2, and a sensor 18 for detecting the displacement, speed and acceleration of the additional mass 6 is provided on the dynamic vibration absorber 3. It is provided. The detection signals from the sensors 15a to 15d and the sensor 18 are servo amplifiers 19a to 19e.
Is input to the subtraction circuit 20. The subtraction circuit 20 calculates the actual displacement and velocity of each floor based on the displacement and velocity of the first floor. That is, the subtraction circuit 20 has 5
Vibration of each floor when the displacement and speed detected by the sensor 15a of the first floor is subtracted from the displacement and speed detected by the sensors 15b to 15d of the first floor, the tenth floor, and the fifteenth floor to make the vibration of the first floor zero. Calculate the size of. Also, anemometer 1
The detection signal from 6 is amplified by the amplifier 21 and the control device 4
Entered in.

A seismometer 22 is buried in the ground so as to detect a longitudinal seismic wave (P wave) and a lateral seismic wave (S wave) propagating on the ground. In addition, seismograph 2 at the time of earthquake occurrence
The detection signal from 2 is amplified by the amplifier 23, and the control circuit 4
Entered in.

The control device 4 has an A / D converter 24 as an input unit, a CPU 25 for calculating a control amount to the dynamic vibration absorber 3,
It has a D / A converter 26 as an output section and an I / O interface circuit 27. A / D converter 24 is a switch 28
Is connected to the subtraction circuit 20 via
The analog signals of the displacement and speed of the building 2 and the additional mass 6 output from the above are converted into digital signals and output to the CPU 25. Further, detection signals from the anemometer 16 and the seismograph 22 are also input to the A / D converter 24, and these detection signals are converted into digital signals and output to the CPU 25.

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 as described later, and the D / A converter 2
Output to 6. Further, the digital signal of the control amount output from the D / A converter 26 is input to the servo driver 29,
The servo driver 29 outputs a torque command current according to the control amount calculated by the CPU 25 to the motor 8 of the dynamic vibration reducer 3.

Reference numeral 30 denotes a memory, which stores each program for damping control, which will be described later, and also stores initial values of respective calculations necessary for damping control, an earthquake flag, an abnormality flag, and the like.

For example, in the memory 30, as shown in FIG.
Vibration suppression mode setting program 30A executed by PU25,
Gain determination program 30B, gain switching program 3
0C and additional mass stop control program 30D are stored. Here, an outline of each control program will be described.

First, the damping mode setting program 30A
Normally controls the wind pressure damping mode, and when a vertical seismic wave (P wave) is detected due to an earthquake, the seismic damping mode is set before the horizontal seismic wave (S wave) propagates. Switch to perform optimum control. Then, even if the earthquake ends, the seismic vibration suppression mode is continued for a predetermined time and then returned to the wind pressure suppression mode, so that control is performed so as to be able to cope with a series of earthquakes.

Further, the gain judgment program 30B has a function of self-diagnosing whether or not the gain of the dynamic vibration reducer 3 is appropriate, for example, based on the natural period of the primary mode of the building 2 during the vibration damping operation. The maximum value of the vibration state for a period is checked, and when the vibration is excited without being attenuated, it is determined that the gain is abnormal and the dynamic vibration reducer 3 is stopped.

Further, the gain switching program 30C switches the gain of the vibration suppression control according to the displacement or wind pressure of the building 2 and the magnitude of the earthquake. In this embodiment, LQ (Li
(nearQuadratic, linear quadratic) The dynamic vibration reducer 3 is damped by the control, and the gain is calculated in the calculation process of the LQ control.

Further, the additional mass stop control program 30D
Means that the additional mass 6 is gently stopped within the movable range of the additional mass 6 so that the additional mass 6 of the dynamic vibration absorber 3 does not collide with the stopper of the base 5 when the building 2 is excessively displaced. The motor 8 is controlled so that

A power source 31 is connected to the control circuit 4 and the servo driver 29, and an emergency stop switch 32 is arranged between the power source 31 and the servo driver 29. The switch 32 normally has contacts, and is opened by being excited by a stop signal from the I / O interface circuit 27 when, for example, an excessive earthquake occurs.

Reference numeral 33 is a high-pass filter (high-pass filter, the filter) which is the subject matter of the present invention, and is a sensor 15a installed on the first floor of the building 2 corresponding to the level of the ground surface.
Is inputted via the servo amplifier 19a, a signal having a frequency lower than a predetermined frequency is attenuated, and a signal having a frequency higher than the predetermined frequency is selectively passed to be inputted to the I / O interface circuit 27. In this embodiment, the sensor 15
Although the detection signal from a is input to the high pass filter 33, the present invention is not limited to this configuration, and the detection signal from the seismograph 22 may be input to the high pass filter 33 via the amplifier 23.

The predetermined frequency is the primary natural frequency of the lowest frequency among the natural frequencies of the building 2 determined from the structure of the building 2 itself. If a seismic wave with a frequency lower than this primary natural frequency is given to this building 2, the building 2
As a rigid body, it only vibrates in the same direction as the vibration direction of the ground surface with the vibration of the ground surface, and the building 2 is hardly deformed. In this way, when the building 2 vibrates without being deformed, the shaking of the building 2 is relatively small,
In principle, the vibration of the building 2 in this case cannot be damped by the vibration damping device 1. Further, the vibration damping device 1 hardly performs the vibration damping operation against the vibration as the rigid body of the building 2.

On the other hand, when a seismic wave having a frequency equal to or higher than the primary natural frequency is applied to the building 2, the building 2 vibrates while being deformed by the resonance phenomenon. The vibration damping device 1 effectively functions against such vibrations. That is, the additional mass 6 is displaced according to the magnitude of the vibration of the building 2 caused by the seismic wave,
The energy of the vibration is canceled out, and the vibration is suppressed. However, when an excessive energy excess seismic wave that cannot be damped by the vibration damping device 1 is generated, the additional mass 6 is excessively driven to suppress the vibration of the building 2 due to the seismic wave, and the stopper (of the base 5 It may collide with the side wall of the recess 5a). In this case, the building 2 may be vibrated by the energy of collision of the additional mass 6 with the stopper. In order to prevent such a situation from occurring, the I / O interface circuit 2
The CPU 25 (including the software as the operation stopping means and the opening / closing means) that has received the detection signal from the high-pass filter 33 via 7 detects from the I / O interface circuit 27 that an excessive large earthquake has occurred. The switch 32 (the operation stopping means, the opening / closing means) outputs an opening signal. As a result, the switch 32 is opened to stop the power supply to the dynamic vibration reducer 3, and the additional mass 6 is mechanically braked by the electromagnetic brake 9, and the additional mass 6 is stopped. In this way, the collision of the additional mass 6 with the stopper due to the abrupt displacement of the additional mass 6 for the purpose of suppressing excessive vibration is prevented.

By providing the high-pass filter 33 as described above, the seismic wave signal having a frequency lower than the primary natural frequency of the building 2 is attenuated. Therefore, even if an excessive earthquake occurs, if the frequency of the seismic wave is less than the primary natural frequency of the building 2, the signal is attenuated by the high-pass filter 33 and is not detected by the CPU 25. .. Therefore, the switch 32 is not opened, and the power supply to the dynamic vibration absorber 3 is not stopped. Therefore, when a seismic wave having a frequency equal to or higher than the primary natural frequency is applied thereafter, the dynamic vibration reducer 3 is controlled by the function of the control device 4, and a normal vibration damping operation can be performed. That is, as described above, the substantial vibration damping operation by the dynamic vibration absorber 3 is hardly performed, and even if the energy is large, there is no possibility that the dynamic vibration absorber 3 vibrates the building 2 It is possible to prevent the power supply of the servo driver 32 from being cut off by the seismic wave of the frequency or less. Therefore, when a seismic wave that can be damped by the dynamic vibration absorber 3 is applied from a state in which the vibration damping operation cannot be performed due to power-off of the servo driver 32, the adverse effect that the vibration damping becomes impossible is prevented.

In particular, in general, the seismic wave has a relatively large energy and a relatively low frequency at the beginning of the generation, and thereafter the energy tends to be relatively small and the frequency relatively high. In the case of such an earthquake wave, the effective vibration damping operation of the vibration damping device 1 can be achieved by adopting the above configuration.

Here, the displacement amount of the building 2 and the ground, which is the basis when the control device 4 performs the vibration damping operation, does not go through the high-pass filter 33, but directly through the respective sensors 15a, 15.
b, 15c, 15d to servo amplifiers 19a, 19b,
It is supplied to the subtraction circuit 20 via 19c and 19d. Therefore, the high-pass filter 33 does not affect the phase delay, and a highly accurate vibration damping operation can be performed.

In this embodiment, when the excessive earthquake occurs, the dynamic vibration absorber 3 is turned off to simultaneously mechanically brake the electromagnetic brake 9 and stop the additional mass 6. Not limited to this, the power supply to the entire vibration damping device may be stopped. Alternatively, even in such a case, the power supply to the servo driver 29 may not be cut off, and conversely, the CPU 25 may control the additional mass 6 to gradually stop.

FIG. 4 shows an example of the high-pass filter 33.
The circuit diagram of an active filter is shown. FIG. 4A shows the primary
Of the active filter of the input terminal T₁And operational amplification
Bowl A ₁Capacitor C between the non-inverting input terminal of₁Connected
And operational amplifier A₁The non-inverting input terminal of is the resistor R₁Through
And is grounded. Also, operational amplifier A₁Output terminal of
Output terminal T_OAnd to the inverting input terminal
Has been done.

The structure of the active filter of FIG. 4A is well known, and its cutoff frequency f _C is expressed by the following equation.

[0042]

[Equation 1]

FIG. 4B shows a second-order active filter.
And the input terminal T₁And operational amplifier A₂Non-inverting input end of
Capacitor C between the child₂, C₃Are connected in series with each other
And operational amplifier A₂The non-inverting input terminal of is the resistor R₃
Grounded through. Also, operational amplifier A₂Output end of
Output terminal T_OConnected to the resistor R ₂
Through the capacitor C₂, C₃Connected to a common connection point of
And the operational amplifier A ₂Output terminal is connected to the inverting input terminal
Has been continued.

The structure of the active filter of FIG. 4B is also well known, and its cutoff frequency f _C is expressed by the following equation.

[0045]

[Equation 2]

Here, as described above, the cutoff frequency f
_C may be set to be slightly lower than the first natural frequency of the building 2.

The circuit diagram shown in FIG. 4 is an example.
It goes without saying that other circuits having similar effects may be applied.

In this embodiment, the high-pass filter is used to pass signals in the frequency band equal to or higher than the primary natural frequency of the building 2, but instead of the high-pass filter, a predetermined frequency including the natural frequency of the building 2 is used. It may be configured to use a bandpass filter that passes signals in the frequency band.

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

Reference numeral 35 is an alarm device, which is used when an abnormality occurs (alarm).
Emit.

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.
It will be described with reference to FIGS.

Further, the CPU 25 repeatedly executes the processing of FIGS. 6 to 8 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 maximum displacement of the top floor of the building 2 (x ₄ max), the time of the timer that counts the seismic damping mode time after the earthquake (several minutes) te, the response simulation by the white noise (white noise) of the ground displacement of 1 m Absolute value of maximum displacement when vibration is not suppressed (xe unit), Absolute value of maximum displacement when vibration is not suppressed at vibration speed of 1 m / sec (xw unit), time t for 2 cycles of vibration of building 2, additional mass Stroke limit position 6 can move without colliding with stopper, lower limit εp of longitudinal seismic wave (P wave) of earthquake, lateral seismic wave (S wave) of earthquake
, Which are stored in the memory 30.

In FIG. 5, the CPU 25 of the control device 4 checks the abnormality of the vibration damping system in step S1 (the following steps will be omitted). For example, the control system of the dynamic vibration absorber 3 or the sensors 15a to 15d, 18, the seismograph 22, the anemometer 1
If there is no abnormality in 6 etc., if there is no abnormality in S2, move to S3 and seismic wave (P wave,
The detection signal of (S wave) is read.

However, if there is an abnormality in S2, the process proceeds to S4 shown in FIG. 7, the control amount u is set to zero, and the occurrence of an abnormality is displayed on the display 34, and in S36 the control amount u =
0 is output to the D / A converter 26 to stop the motor 8 and stop the vibration damping operation by the dynamic vibration reducer 3. Then, until the abnormal point is repaired and the state returns to the normal state, S1, S2,
S4 and S36 are repeated.

At S5, it is checked whether the earthquake flag = 0. The earthquake flag is set to "0" when there is no normal earthquake (before an earthquake occurs), and is set to "1" when it is determined that an earthquake occurs.

Therefore, when the earthquake flag = 0, the process goes to S6, and it is checked whether the amplitude Ap of the longitudinal seismic wave (P wave) is larger than the lower limit value εp. When an earthquake occurs,
First, a vertical seismic wave (P wave) having a high propagation speed propagates to the building 2, and a lateral seismic wave (S wave) propagates with a slight delay. A structure such as the building 2 has sufficient strength for vertical vibration, but in the case of horizontal vibration, there is a resonance phenomenon, so it is necessary to suppress the vibration by the dynamic vibration reducer 3.

The main causes for the building 2 to vibrate in the lateral direction are an increase in wind pressure and rolling due to an earthquake. The vibration of the building 2 due to wind pressure vibrates slowly at a low frequency even if the amplitude is the same. On the other hand, the vibration of the building 2 due to the earthquake is abrupt and complicated, but often violently shakes at a higher frequency than in the case of wind pressure.

Therefore, the CPU 25 normally executes the processing of the wind pressure damping mode suitable for the vibration due to the wind pressure shown in FIG. 6, and when the earthquake occurs, it is suitable for the vibrations after S6 shown in FIG. 5 and the vibration caused by the earthquake shown in FIG. The seismic damping mode processing is executed.

Here, the processing of the wind pressure damping mode that is normally executed will be described first, and then the processing of the seismic damping mode will be described.

I "Wind Pressure Damping Mode" In step S6, the amplitude Ap of the P wave is the lower limit value ε.
If it is smaller than p, the flow shifts to S7 shown in FIG. 6 to set the earthquake flag to "0" and display "wind pressure damping mode" on the display 34.

Subsequently, in S8, the peak hold timer t for gain abnormality detection is incremented by 1,
In S9, it is checked whether or not the time T for two cycles based on the natural cycle of the primary mode of the building 2 has elapsed. It should be noted that the time T for two cycles is previously input to the memory 30, and T =
It is determined by the formula of 2 (2π / ω ₁ ) × F. However, ω ₁ is the primary natural frequency (0.5 rad / S) of the building 2, and F is the control sampling frequency (200 Hz).

In S9, when the time T for two cycles has not yet passed, the processes of S10 to S12 described later are not executed, and the process proceeds to S13, in which the sensors 15a to 15a installed on the plural floors of the building 2 The displacement, velocity, and acceleration << X >> (hereinafter, state displacement vector is represented by << X >>) detected by the sensor 18 of 15d and the additional mass 6 are read. Therefore,
The displacement, velocity and acceleration << X >> of the building 2 and the additional mass 6 are read and stored in the memory 30 until the time of the timer t reaches the time T of two cycles.

However, when the time T elapses in S9, the process proceeds to S10, where the limit value X ₄ lm of the displacement of the top floor is set.
t is the absolute value of the maximum displacement (Xw
(unit) is updated to the value obtained by multiplying the maximum wind speed wp (S1
0). Subsequently, of the two cycles of displacement stored in the memory 30 in S11, the maximum displacement X ₄ max on the top floor of the building 2 and S1
Compare with the limit value X ₄ lmt obtained by 0.

In S11, when the value of the maximum displacement X ₄ max is smaller than the limit value X ₄ lmt, the vibration of the building 2 is damped by the vibration damping operation of the dynamic vibration reducer 3, so it is determined that there is no abnormality. In S12, the values of the maximum displacement X ₄ max, the timer t, and the maximum wind speed wp stored in the memory 30 are reset to zero. Then, in S13, the displacements and velocities of the building 2 and the additional mass 6 and the accelerations << X >> detected by the sensors 15a to 15d are read.

However, in S11, the maximum displacement X ₄ ma
If x is larger than the limit value X ₄ lmt, the dynamic vibration absorber 3
Although the building 2 is vibrated and the vibration is large despite the fact that the control gain is being controlled, it is determined that the control gain << F >> (hereinafter, the control gain vector is represented by << F >>) is abnormal. Then, in S14, the abnormality flag = 1 is set and an alarm is issued.
Then, the flow shifts to S4 described above, the control amount u is set to zero, "control gain abnormality" is displayed on the display 34, and the control amount u = 0 is output in S36 to stop the dynamic vibration reducer 3.

Returning to FIG. 6, in S15, the displacement X of the top floor is determined.
_FourAbsolute value of | X_FourIs the most recent value stored in memory 30
Large displacement X_FourCheck if it is greater than max. This strange
Rank X _FourAbsolute value of | X_FourIf | is larger, go to S16
Maximum displacement X_Fourmax is the current displacement X_FourAbsolute value of | X_Four
It is updated to | and stored in the memory 30, and the process proceeds to S17. or,
This time displacement X_FourAbsolute value of | X_FourWhen ｜ is smaller
Moves to S17 without updating and is detected by the anemometer 16.
Read the wind speed w.

At the next step S18, the absolute value | w | of the wind speed w detected this time is the maximum wind speed wp stored in the memory 30.
I am checking if it is larger than this, this time the wind speed w
When the absolute value | w | of is larger, the process moves to S19, the maximum wind speed wp is updated to the current value, and the process goes to S20.

If the current wind speed is lower, the control amount u to the dynamic vibration absorber 3 is calculated without updating, and the process proceeds to S20.

In S20, the control gain << Fw >> of the wind pressure damping mode by the LQ control which will be described later is obtained, and the following equation (1) is obtained.

[0071]

[Equation 3]

The control amount u is calculated by Then, the control amount u calculated in the wind pressure damping mode is output in S36.

Therefore, when there is no normal earthquake, S7 to S2
Since the process of 0 is executed and the dynamic vibration absorber 3 is controlled by using the gain corresponding to the displacement caused by a relatively small external force such as wind, that is, the gain << Fw >> when the building 2 does not vibrate, the dynamic vibration absorber 3 is controlled slowly by wind pressure. The additional mass 6 can be moved at a speed suitable for damping the displacement, and good damping can be achieved.

II "Seismic vibration suppression mode" In S6 shown in FIG. 5, the seismic wave is propagated by the occurrence of the earthquake, and the longitudinal seismic wave (P
When the wave) becomes equal to or higher than the lower limit value εp, the seismic damping mode is set. That is, in S6, when the P wave has the amplitude Ap> εp, the process proceeds to S21 and the earthquake flag is set to "1" to enter the seismic damping mode.

In the next S51, the vibration detection signal of the ground surface sensor 15a inputted via the servo amplifier 19a, the high-pass filter 33 and the I / O interface circuit 27 is checked, and the seismic wave detected here is preset. It is determined whether the seismic wave is an excessive earthquake wave having a vibration energy equal to or higher than a threshold value. If the result of the determination is not an excessively large seismic wave, that is, if the seismic wave has an energy within a range that can be damped by the dynamic vibration absorber 3, the process proceeds to S22. If the result of the determination is an excessively large seismic wave, the power supply to the servo driver 29 whose switch 32 is opened as described above is stopped, and the additional mass 6 is applied by the simultaneous electromagnetic brake 9.
Is braked and the operation of the additional mass 6 is stopped.

In the next processing from S22 to S30, the gain abnormality determination is performed similarly to S8 to S16 of the wind pressure damping mode described above, and the displacement for two cycles based on the natural cycle of the primary mode of the top floor of the building 2 is performed. Check and check maximum value X
_{If 4} max is smaller than the limit value X ₄ lmt due to the earthquake, normal vibration suppression control is performed, and conversely, when the maximum displacement X ₄ max this time is larger than the limit value X ₄ lmt, it means that the gain is abnormal. judge.

At S31, it is checked whether the amplitude of the lateral seismic wave (S wave) detected by the seismograph 22 is smaller than the lower limit value εs. Therefore, when an earthquake (S wave) from the epicenter is detected by the seismograph 22 in S31 and the amplitude As of the S wave is larger than the lower limit value εs, the process proceeds to S32 and the seismic vibration suppression mode timer te is reset to zero, S
In 33 to S36, the control amount u according to the magnitude of the displacement of the building 2
Is calculated and the additional mass 6 is moved.

However, in S31, whether the vertical seismic wave (P wave) is detected or the horizontal seismic wave (S wave) is still detected.
If is not detected, the process proceeds to S37, where the timer te is incremented, and it is checked in S38 whether the count time of the timer te has reached the standby time Te (about several minutes) preset in the memory 30. And still waiting time T
If e has not been reached (te <Te), the process proceeds to S33. Therefore, the standby state of the seismic damping mode is maintained until the vertical seismic wave (P wave) is detected in S6 and the horizontal seismic wave (S wave) is detected.

As described above, the P wave of the seismic wave propagates first, and the S wave propagates with a slight delay. When a seismic wave (S wave) larger than the lower limit εs is detected while waiting in the seismic damping mode as described above, the timer te is reset to zero in S32 as described above.

Subsequently, the amplitude As of the S wave is determined by the memory 30.
It is checked whether it is larger than the maximum amplitude ep stored in (S33). If the current amplitude As is larger, the maximum amplitude ep is updated to the current amplitude in S34 and stored in the memory 30, and the process proceeds to S35.

When the amplitude of the S wave this time is smaller, the control amount u to the dynamic vibration absorber 3 is calculated without updating, and the process proceeds to S35.

At S35, the control gain << F >> of the seismic vibration suppression mode by LQ control, which will be described later, is obtained, and the following equation (2) is obtained.

[0083]

[Equation 4]

The control amount u is calculated by Then, the control amount u calculated in the seismic damping mode is output in S36. In the next process, since the earthquake flag = 1 is set in S21, the process directly moves from S5 to S22, and S6 and S21 are omitted.

Therefore, when the seismic wave (S wave) propagates, the processing of S21 to S40 is executed, and the gain corresponding to the abrupt displacement due to the earthquake, that is, the gain << Fe >> when the building 2 vibrates at a high frequency is set. Since the dynamic vibration reducer 3 is controlled by using the vibration absorber 3, the additional mass 6 can be moved at a speed suitable for suppressing abrupt vibration due to a lateral earthquake to effectively suppress the vibration. Therefore, even if a sudden displacement is detected when an earthquake occurs, the additional mass 6
Is not driven until it collides with the stopper of the base 5, the limit switch is turned on and the vibration cannot be suppressed as in the conventional case, and the impact to the stopper is not transmitted to the building 2. It is like this.

The seismic wave (S wave) stops and the lower limit value ε
When it becomes equal to or less than p, the seismic vibration suppression mode is continued until the wind pressure vibration suppression mode is switched to immediately, the process moves from S31 to S37, the timer te is incremented and the waiting time Te elapses (S38). Therefore, even if the aftershock or a series of earthquakes in which the seismic wave propagates again even if the earthquake stops, the seismic damping mode is maintained for the predetermined time Te after the earthquake stops, so The building 2 can be satisfactorily damped even against a sudden input change caused by the third earthquake.

Then, in S38, when the earthquake does not occur even after the preset waiting time Te has elapsed, S
In 39, the earthquake flag is set to "0" and the maximum amplitude ep is reset to zero in S40. Then, the above-mentioned S35, S
The process of 36 is performed. Further, in S40-1, the timer te
To clear. Therefore, in the next process, when the amplitude of the P wave is smaller than the lower limit value εp in S6, the wind pressure damping mode is returned to again.

As described above, even if the earthquake stops during the seismic vibration suppression mode, the seismic vibration suppression mode is continued for the time Te without immediately switching to the wind pressure vibration suppression mode. The dynamic vibration absorber 3 can be controlled by the gain << Fe >> according to the abrupt displacement caused by the earthquake.

Here, a calculation method for calculating the control amount u in S20 and S35 will be described.

First, the determination of the wind pressure control mode gain << Fw >> and the seismic damping mode gain << Fe >> will be described. When obtaining the gains << Fw >> and << Fe >>,
Consider a dynamic model of the N-story building 2 and the dynamic vibration absorber 3 as shown in FIG. In FIG. 9, m is a mass, K is a spring element, C
Is a damping element. Then, an optimum regulator for the dynamic model of FIG. 9 is designed and applied to the vibration damping device 1.

That is, the evaluation function J is obtained by a method called LQ (Linear Quadratic) control, and the gains Fw and Fe of the control system are determined so that the evaluation function J is minimized.

The dynamic model is the mass msi from the 1st floor to the Nth floor.
And a damping element with a spring damping constant csi of stiffness ksi. Further, the dynamic vibration reducer 3 is represented by the additional mass ma and the control amount u.

The absolute displacement of each floor is ysi, and the displacement of the dynamic vibration absorber 3 is ya. Here, the relative displacement xsi between the ground floor yso and each floor is expressed as xsi = ysi−yso (3), and the top floor (m _SN and the added mass 6 of the dynamic vibration absorber 3)
The relative displacement xa with respect to (ma) is expressed as xa = ya−y _SN (4).

State displacement vector

[0095]

[Outer 1]

Then, (however,

[0097]

[Outside 2]

Is the displacement, velocity and acceleration of the additional mass 6, respectively, and X _{S1 to} X _SN are the displacements of the building 2,

[0099]

[Outside 3]

Is the speed of building 2. ) The equation of state of this system is

[0101]

[Equation 5]

Is expressed as

[0103]

[Equation 6]

However, in the equation (6), I represents a unit matrix and O represents a zero matrix. The same applies to the following.

[0105]

[Equation 7]

The mass matrix M, the stiffness matrix K, and the damping matrix C are

[0107]

[Equation 8]

It can be expressed as Here, in order to suppress the displacement of the building 2, the following evaluation function J
To set.

[0109]

[Equation 9]

However, << X >> is the state quantity of each mass point (<< X >> ^T
<< X >> is proportional to the area), Q is a weight for the feedback amount, and R is a constraint regarding the dynamic vibration reducer u. Therefore, R
When is small, the acceleration of the additional mass 6 is large, and when R is large, the acceleration of the additional mass 6 is small.

Here,

[0112]

[Equation 10]

Then, the displacement of the additional mass 6 is large when qa is small, and the displacement of the additional mass 6 is small when qa is large.

[0114]

[Equation 11]

Therefore, the gains << Fw >> and << Fe >> are

[0116]

[Equation 12]

## EQU14 ## P is obtained as a solution of the Riccati equation (15).

[0118] ^{A T P + PA + Q-} PBR -1 B T P = 0 ... (15) The weight Q, in R, the gain "Fw", displacement factor of the dynamic vibration reducer 3 corresponding to "Fe" qa, additional mass 6 The acceleration coefficient R is qw _and rw for wind pressure and q for earthquake
If e and re, the external force due to the earthquake is several times larger than the wind pressure, so set qw << qe, rw << re and obtain the gain F by the above procedure.

The control amount u is calculated based on the gain F thus obtained, and is output to the motor 8 of the dynamic vibration reducer 3. Therefore, the additional mass 6 moves in the damping direction by being controlled by the control amount u by the gain << Fw >> in the wind pressure damping mode, and performs the damping operation by the control amount u by the gain << Fe >> in the earthquake damping mode. To be driven.

In the above embodiment, the vibration damping device for damping the building 2 is given as an example, but the invention is not limited to this, and the dynamic vibration reducer 3 is not limited to the structure (for example, a bridge, a tower, an elevated building). Of course, it can also be applied to objects, stadiums, etc.).

[0121]

As described above, according to the invention of claim 1,
Since the operation of the additional mass is prevented from being stopped by the seismic wave of the frequency at which the vibration suppressor does not originally operate, the energy of the seismic wave at the frequency at which the vibration suppressor originally operates is large. The operation of the additional mass is stopped only when the capacity of is exceeded. Therefore, in such a case, the additional mass can be safely stopped.
It is possible to prevent the collision of non-mass to the structure, improve safety, and minimize the case of the operation of the additional mass to the minimum necessary, so that the vibration damping operation is performed effectively. can do. Further, by adopting a configuration in which the filter is not interposed in the control loop in which the vibration damping operation is performed by the displacement detection signal output from the displacement sensor of the structure and the ground, the accuracy of the vibration damping operation is reduced due to the phase delay of the filter or the like. Can be prevented.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram 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 circuit diagram of an example of a high-pass filter which is a main part of the present invention.

FIG. 5 is a diagram showing items stored in a memory.

FIG. 6 is a flowchart for explaining a process executed by the CPU of the vibration damping device.

FIG. 7 is a flowchart for explaining processing in a wind pressure damping mode that is executed subsequent to the processing in FIG.

FIG. 8 is a flowchart for explaining a process of seismic damping mode that is executed subsequent to the process of FIG.

FIG. 9 is a diagram showing a vibration model of a building and a dynamic vibration reducer.

[Explanation of symbols]

1 Vibration Control Device 2 Building 3 Dynamic Vibration Absorber 4 Control Device 6 Additional Mass 8 AC Servo Motor 15a to 15d, 18 Sensor 16 Anemometer 22 Seismometer 25 CPU (Including Software as Operation Stopping / Opening / Closing Means) 32 Switch (Operation stopping means, opening / closing means) 33 High-pass filter (filter)

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

Claims (3)

[Claims] 1. A drive signal is generated based on a detection signal from a sensor that detects a displacement of a structure and the ground, and an actuator is driven by the drive signal to move an additional mass to suppress vibration of the structure. In a vibration damping device that vibrates, a filter that selectively passes a signal in a predetermined frequency band including the frequency of the natural frequency of the structure among the signals detected by the sensor, and the detection signal through the filter. Is input and it is determined that the vibration of the structure cannot be damped by the movement of the additional mass, the vibration damping device has a motion stopping unit that stops the motion of the additional mass. 2. The vibration damping device according to claim 1, wherein the operation stopping means is an opening / closing means for stopping power supply to the drive signal generating means for generating the drive signal. 3. The vibration damping device according to claim 1, wherein the filter is a high-pass filter that selectively passes a signal in a frequency band equal to or higher than the primary natural frequency of the structure.