Variable frequency tuning liquid damper and frequency control method thereof

Abstract

The present application provides a variable frequency tuning liquid damper and a frequency control method thereof. The damper comprises a closed container, a damping liquid and a frequency adjusting assembly; the frequency adjusting assembly comprises a control unit and an angle adjusting member; the control unit obtains a target tilting angle of the closed container according to a tuning frequency of the damper, an effective side length of the liquid surface of the closed container in a horizontal state along a direction of external load and an average water depth of the liquid surface of the closed container in a tilting state; and the angle adjusting member controls the tilting angle of the closed container. The method comprises detecting the tuning frequency of the damper; calculating the target tilting angle of the closed container according to the tuning frequency of the damper, the effective side length of the liquid surface of the closed container in the horizontal state along the direction of external load and the average water depth of the liquid surface of the closed container in the tilting state; and driving the closed container to rotate to the target tilting angle by the angle adjusting member. The present application has the advantages of adjustable tuning frequency of the damper and convenient adjustment.

Description

Technical Field

[0001] This invention relates to the field of damper vibration reduction, and more particularly to a variable frequency tuned liquid damper and its frequency tuning control method. Background Technology

[0002] High-rise and super high-rise buildings are prone to significant vibrations under dynamic loads such as wind. Current technologies commonly employ tuned mass dampers (TMDs) and tuned liquid dampers (TLDs) for vibration control. TLDs, using liquid as the inertial element, eliminate the need for complex springs or guiding systems, offering advantages such as simple structure and low cost. Furthermore, they can be integrated with functional water tanks (such as fire-fighting water tanks) without occupying additional space, facilitating installation and maintenance. These factors have led to the widespread application of TLDs in vibration control for high-rise and super high-rise buildings.

[0003] Existing TLDs typically target a specific mode of structural vibration reduction, designing the damper's tuning frequency to match the structure's natural frequency in that mode. In other words, traditional TLDs only tune to a single natural frequency, and their vibration reduction effect depends on the matching between the structural's principal response frequency and the damper's design frequency. However, in practical engineering, the principal response frequency of high-rise buildings under random loads may change over time and under varying load conditions. When the structural's principal response frequency deviates from the damper's design frequency, the TLD's vibration reduction performance will significantly decrease. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a variable frequency tuned liquid damper with adjustable and convenient damping frequency and its frequency control method.

[0005] To solve the above-mentioned technical problems, the technical solution proposed by this invention is as follows: A variable frequency tuned liquid damper includes a closed container, a damping fluid, and a frequency adjustment component. The damping fluid is disposed within the closed container, and a free-flowing gap is left between the damping fluid and the top of the closed container. The frequency adjustment component is connected to a controlled structure and includes a control unit and an angle adjustment component that adjusts the effective side length of the free surface of the damping fluid in the external load direction. The control unit obtains a target tilt angle of the closed container based on the tuning frequency of the damper, the effective side length of the liquid surface in the external load direction when the closed container is horizontal, and the average water depth of the liquid surface when the closed container is tilted, and sends the target tilt angle to the angle adjustment component. The angle adjustment component is driven and connected to the closed container to control the tilt angle of the closed container and adjust the damper to the target tuning frequency.

[0006] As a further improvement to the above technical solution: The control unit obtains the target tilt angle of the closed container according to the following formula: L c =L / cosα in, This is the tuning frequency of the damper. This refers to the effective side length of the liquid surface along the direction of the external load when the closed container is tilted. The average water depth is the liquid level when the closed container is tilted. Let L be the acceleration due to gravity, L be the effective side length of the liquid surface along the direction of the external load in a horizontal state, and α be the tilt angle of the closed container in an inclined state.

[0007] The frequency adjustment component also includes an angle detection element connected to the controller. The angle detection element detects the real-time tilt angle of the closed container and sends it to the controller. The controller compares the real-time tilt angle with the target tilt angle. When the real-time tilt angle and the target tilt angle are less than the allowable error value, the controller sends a stop rotation signal to the angle adjustment element. When the real-time tilt angle and the target tilt angle are greater than the allowable error value, the controller sends an error correction drive signal to the angle adjustment element until the real-time tilt angle and the target tilt angle are less than the allowable error value.

[0008] The control unit includes a controller, a driver, and an encoder. The controller sends an angle adjustment command based on the difference between the real-time tilt angle and the target tilt angle. The driver converts the angle adjustment command into voltage and current signals to drive the angle adjustment component. The encoder provides real-time feedback on the real-time angle of the angle adjustment component.

[0009] It also includes an adjustment base and a connector. The angle adjustment component is connected to the controlled structure through the adjustment base, and the drive end of the angle adjustment component is connected to the bottom of the closed container through the connector.

[0010] The angle adjustment component is a drive motor, the control unit is a motor control unit, and the drive motor is connected to the motor control unit via a cable.

[0011] The tilt angle of the closed container can be adjusted from 0° to 90°.

[0012] A frequency modulation control method for the aforementioned variable frequency tuned liquid damper includes the following steps: Step 1) Real-time detection of changes in the vibration frequency of the structure. When a change in the vibration frequency of the structure is detected, the tuning frequency of the damper is detected. Step 2) Calculate the target tilt angle of the closed container based on the damper's tuning frequency, the effective side length of the liquid surface along the external load direction in the horizontal state of the closed container, and the average water depth of the liquid surface in the tilted state of the closed container. Step 3) Drive the closed container to rotate to the target tilt angle by adjusting the angle adjustment component, so as to change the effective side length of the free liquid surface of the damping fluid in the direction of external load and realize the dynamic adjustment of the tuning frequency.

[0013] As a further improvement to the above technical solution: In step 2), the target tilt angle is obtained according to the following formula: L c =L / cosα in, This is the tuning frequency of the damper. This refers to the effective side length of the liquid surface along the direction of the external load when the closed container is tilted. The average water depth is the liquid level when the closed container is tilted. Let L be the acceleration due to gravity, L be the effective side length of the liquid surface along the direction of the external load in a horizontal state, and α be the tilt angle of the closed container in an inclined state.

[0014] In step 3), the real-time tilt angle of the closed container is detected by the angle detection device. The controller compares the real-time tilt angle with the target tilt angle. When the real-time tilt angle is less than the target tilt angle, the controller sends a stop rotation signal to the angle adjustment device. When the real-time tilt angle is greater than the target tilt angle, the controller sends an error correction drive signal to the angle adjustment device until the real-time tilt angle is less than the target tilt angle.

[0015] Compared with the prior art, the advantages of the present invention are as follows: The frequency adjustment component of this invention includes a control unit and an angle adjustment component. Specifically, this invention adjusts the effective side length of the damping fluid's free surface along the external load direction by changing the tilt angle of the closed container through the combination of the control unit and the angle adjustment component, thereby dynamically adjusting the damper to the target tuning frequency. This allows the damper to adapt to changes in the main frequency of the controlled structure under different operating conditions. Simultaneously, the target tilt angle of the closed container is obtained based on the damper's tuning frequency, the effective side length of the liquid surface along the external load direction in the horizontal state, and the average water depth of the liquid surface in the tilted state. This ensures high precision in the tilt angle of the closed container, achieving accurate adjustment of the damper's target tuning frequency. Furthermore, it allows the tuning frequency to be adjusted in real time according to changes in the damper's tuning frequency, effectively expanding the applicable frequency range of the TLD and significantly improving the damping efficiency of the damper under various operating conditions.

[0016] As can be seen, this invention, by combining a closed container with damping fluid, an angle adjustment component with controllable rotation angle, and a control unit, achieves dynamic and precise adjustment of the target tuning frequency of the damper by changing the tilt angle of the closed container to adjust the effective side length of the free liquid surface of the damping fluid in the direction of external load. Furthermore, it maintains high vibration reduction efficiency over a wider frequency band, significantly improving the safety and comfort of high-rise and super high-rise buildings under wind loads, earthquakes, and other dynamic forces. It has a wide range of applications and is simple, compact, and low-cost. The method of this invention also possesses the above advantages and is convenient and efficient to operate. Attached Figure Description

[0017] The invention will now be described in more detail with reference to embodiments and the accompanying drawings. Figure 1 This is a front view (horizontal state) of the variable frequency tuned liquid damper of the present invention. Figure 2 This is a front view (tilted state) of the variable frequency tuned liquid damper of the present invention. Figure 3 This is a flowchart of the frequency modulation method of the present invention; Figure 4 This is a flowchart illustrating the implementation of the frequency modulation method of the present invention.

[0018] The labels in the diagram represent: 1. Sealed container; 2. Damping fluid; 3. Frequency adjustment assembly; 31. Angle adjustment component; 32. Control unit; 4. Adjustment component base; 5. Connector; 6. Cable. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments, but this does not limit the scope of protection of the present invention.

[0020] Figure 1 and Figure 2An embodiment of the variable frequency tuned liquid damper of the present invention is shown, which is applicable to vibration reduction control of high-rise and super high-rise buildings. In this embodiment, the variable frequency tuned liquid damper includes a closed container 1, a damping liquid 2, and a frequency adjustment component 3. The damping liquid 2 is disposed within the closed container 1, and a free-flowing gap is left between the damping liquid 2 and the top of the closed container 1 to allow the damping liquid 2 to freely flow within the closed container 1, achieving vibration reduction. Its structure is simple and low-cost. In this embodiment, the frequency adjustment component 3 is connected to the controlled structure. The frequency adjustment component 3 includes a control unit 32 and an angle adjustment component 31 that adjusts the effective side length of the free surface of the damping liquid 2 in the external load direction. The control unit 32 obtains the target tilt angle of the closed container 1 based on the tuning frequency of the damper, the effective side length of the liquid surface in the external load direction when the closed container 1 is horizontal, and the average water depth of the liquid surface when the closed container 1 is tilted, and sends the target tilt angle to the angle adjustment component 31. The angle adjustment component 31 drives the closed container 1 to control the tilt angle of the closed container 1 and adjust the damper to the target tuning frequency.

[0021] The frequency adjustment component 3 of this invention is equipped with a control unit 32 and an angle adjustment component 31. That is, this invention adjusts the effective side length of the free surface of the damping fluid 2 along the external load direction by changing the tilt angle of the closed container 1 through the combination of the control unit 32 and the angle adjustment component 31, thereby dynamically adjusting the damper to the target tuning frequency. This allows the damper to adapt to changes in the main frequency of the controlled structure under different operating conditions. Simultaneously, the target tilt angle of the closed container 1 is obtained based on the tuning frequency of the damper, the effective side length of the liquid surface along the external load direction in the horizontal state of the closed container 1, and the average water depth of the liquid surface in the tilted state of the closed container 1. This ensures high precision in the tilt angle of the closed container 1, thereby achieving accurate adjustment of the target tuning frequency of the damper. Furthermore, the tuning frequency can be adjusted in real time according to changes in the tuning frequency of the damper, effectively expanding the applicable frequency range of the TLD, thus significantly improving the vibration reduction efficiency of the damper under various operating conditions, and offering convenient and efficient adjustment.

[0022] As can be seen, the present invention combines a closed container 1 with damping fluid 2, an angle adjustment component 31 with controllable rotation angle, and a control unit 32. By changing the tilt angle of the closed container 1 to adjust the effective side length of the free liquid surface of the damping fluid 2 in the direction of external load, the present invention achieves dynamic and precise adjustment of the target tuning frequency of the damper. It can maintain high vibration reduction efficiency over a wider frequency band, significantly improving the safety and comfort of high-rise and super high-rise buildings under the dynamic action of wind loads, earthquakes, etc. It has a wide range of applications and a simple, compact structure with low cost.

[0023] In this embodiment, the control unit 32 obtains the target tilt angle of the closed container 1 according to the following relationship: (1) L c =L / cosα (2) in, The tuning frequency of the damper can be detected by a sensor mounted on the controlled structure. This refers to the effective side length of the liquid surface along the direction of the external load when the closed container 1 is tilted. The average water depth is taken as the liquid level when the closed container 1 is tilted, i.e., the water depth when the closed container 11 is placed horizontally. This is the acceleration due to gravity, typically g = 9.81 m / s². 2 L is the effective side length of the liquid surface along the external load direction in the horizontal state of the closed container 1, and α is the tilt angle of the closed container 1 in the tilted state.

[0024] Using the above formula, the tuning frequency of the damper can be obtained in real time. The average water depth of the liquid surface in the closed container 1 under tilted conditions. The effective side length of the liquid surface along the direction of external load in the closed container 1 when it is tilted. Obtain precise target tilt angle α When the dominant frequency of the vibration response of the controlled structure changes, the angle adjustment component 31, which controls the rotation angle, adjusts the closed container 1 to the target tilt angle. α This changes the effective side length of the free surface of the liquid in the direction of the external load, thereby achieving dynamic and precise adjustment of the target tuning frequency of the damper.

[0025] Furthermore, the frequency adjustment component 3 also includes an angle detection element connected to the controller. The angle detection element detects the real-time tilt angle of the enclosed container 1 and sends it to the controller. The controller compares the real-time tilt angle with the target tilt angle. When the real-time tilt angle is less than the target tilt angle, the controller sends a stop rotation signal to the angle adjustment component 31; when the real-time tilt angle is greater than the target tilt angle, the controller sends an error correction drive signal to the angle adjustment component 31 until the real-time tilt angle is less than the target tilt angle. This enables precise control of the rotation angle of the angle adjustment component 31 during dynamic processes, thereby further precisely adjusting the damper to the target tuning frequency, better ensuring the effective delivery of the main frequency of the controlled structure under different operating conditions, and achieving better energy dissipation and vibration reduction effects.

[0026] Furthermore, the control unit 32 includes a controller, a driver, and an encoder. The controller sends an angle adjustment command based on the difference between the real-time tilt angle and the target tilt angle. The driver converts the angle adjustment command into voltage and current signals to drive the angle adjustment component 31. The encoder provides real-time feedback on the tilt angle of the angle adjustment component 31 to facilitate rapid adjustment of the enclosed container 1 to the target tilt angle.

[0027] In this embodiment, the variable frequency tuned liquid damper further includes an adjusting base 4 and a connecting member 5. The angle adjusting member 31 is connected to the controlled structure via the adjusting base 4, which is used to adjust the angle adjusting member 31 and transmit vibrations. The driving end of the angle adjusting member 31 is connected to the bottom of the closed container 1 via the connecting member 5, thereby transmitting the vibrations of the controlled structure sequentially through the adjusting base 4, the angle adjusting member 31, and the connecting member 5 to the closed container 1, achieving effective vibration reduction; and enabling effective adjustment of the tilt angle of the closed container 1. In this embodiment, the tilt angle adjustment range of the closed container 1 is 0° to 90°.

[0028] In this embodiment, the connector 5 is a hinged structure, the angle adjustment component 31 is a servo motor, and the drive motor is connected to the control unit 32 via cable 6. This allows the enclosed container 1 to rotate around a horizontal axis under the drive of the servo motor. The adjustment component base 4 is connected to the controlled structure by bolt fixing or welding.

[0029] In this embodiment, when the controlled structure experiences large-scale vibration, the vibration is transmitted to the damper through the adjusting base 4, causing the damping fluid 2 in the closed container 1 to oscillate back and forth, thereby dissipating the vibration energy of the structure and achieving vibration reduction. When the vibration frequency of the controlled structure changes, the target tilt angle α that the closed container 1 needs to be adjusted can be calculated according to formulas (1) and (2). The control unit 32 continuously adjusts the driving voltage and current according to the target tilt angle to achieve high-precision closed-loop position control.

[0030] like Figure 3 and Figure 4 As shown, a frequency modulation control method for the aforementioned variable frequency tuned liquid damper includes the following steps: Step 1) Real-time detection of changes in the vibration frequency of the controlled structure. When a change in the vibration frequency of the structure is detected, the tuning frequency of the damper is detected. Step 2) Calculate the target tilt angle of the closed container 1 based on the damper's tuning frequency, the effective side length of the liquid surface along the external load direction in the horizontal state of the closed container 1, and the average water depth of the liquid surface in the tilted state of the closed container 1. Step 3) Drive the closed container 1 to rotate to the target tilt angle by using the angle adjustment component 31, so as to change the effective side length of the free liquid surface of the damping liquid 2 in the direction of external load and realize the dynamic adjustment of the tuning frequency.

[0031] The frequency control method of this invention also possesses the aforementioned advantages of dampers, and by real-time detection of the vibration frequency changes of the controlled structure, the target tilt angle of the closed container 1 can be obtained, thereby better realizing the dynamic and precise adjustment of the target tuning frequency of the damper. Furthermore, its adjustment is convenient and highly efficient.

[0032] Further, in step 2), the target tilt angle is obtained according to the following formula: (1) L c =L / cosα (2) in, This is the tuning frequency of the damper. This refers to the effective side length of the liquid surface along the direction of the external load when the closed container 1 is tilted. The average water depth of the liquid surface in the closed container 1 when it is tilted. Let L be the acceleration due to gravity, L be the effective side length of the liquid surface along the direction of the external load in the horizontal state of the closed container 1, and α be the tilt angle of the closed container 1 in the tilted state.

[0033] Further, in step 3), the real-time tilt angle of the enclosed container 1 is detected by the angle detection device. The controller compares the real-time tilt angle with the target tilt angle. When the real-time tilt angle is less than the allowable error value, the controller sends a stop rotation signal to the angle adjustment device 31. When the real-time tilt angle is greater than the allowable error value, the controller sends an error correction drive signal to the angle adjustment device 31 until the real-time tilt angle is less than the allowable error value. Through this process, the control unit 32 can achieve precise control of the rotation angle of the enclosed container 1 during dynamic processes, thereby further precisely adjusting the damper to the target tuning frequency, better ensuring the effective submission of the main frequency of the controlled structure under different operating conditions, and achieving better energy dissipation and vibration reduction effects.

[0034] In this embodiment, as Figure 4 As shown, the implementation process of the frequency modulation control method of the variable frequency tuned liquid damper includes: First, the controller sends an angle adjustment command based on the difference between the real-time tilt angle and the target tilt angle. The driver converts the angle adjustment command into voltage and current signals and applies them to the motor stator, thereby generating a rotating magnetic field. The motor rotor moves under the action of electromagnetic torque, and at the same time, the encoder feeds back the real-time tilt angle of the motor rotor to the controller. The controller compares the real-time tilt angle with the target tilt angle. If there is an error, it sends an error correction drive signal until the motor rotates to the set position.

[0035] Although the invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A variable frequency tuned liquid damper, characterized in that, The device includes a sealed container, a damping fluid, and a frequency adjustment assembly. The damping fluid is disposed within the sealed container, with a free-flowing gap between the damping fluid and the top of the sealed container. The frequency adjustment assembly is connected to the controlled structure and includes a control unit and an angle adjustment component that adjusts the effective side length of the free surface of the damping fluid in the external load direction. The control unit obtains the target tilt angle of the sealed container based on the tuning frequency of the damper, the effective side length of the liquid surface in the external load direction when the sealed container is horizontal, and the average water depth of the liquid surface when the sealed container is tilted, and sends the target tilt angle to the angle adjustment component. The angle adjustment component is driven and connected to the sealed container to control the tilt angle of the sealed container and adjust the damper to the target tuning frequency.

2. The variable frequency tuned liquid damper according to claim 1, characterized in that, The control unit obtains the target tilt angle of the closed container according to the following formula: L c =L / cosα in, This is the tuning frequency of the damper. This refers to the effective side length of the liquid surface along the direction of the external load when the closed container is tilted. The average water depth is the liquid level when the closed container is tilted. Let L be the acceleration due to gravity, L be the effective side length of the liquid surface along the direction of the external load in a horizontal state, and α be the tilt angle of the closed container in an inclined state.

3. The variable frequency tuned liquid damper according to claim 2, characterized in that, The frequency adjustment component also includes an angle detection element connected to the controller. The angle detection element detects the real-time tilt angle of the closed container and sends it to the controller. The controller compares the real-time tilt angle with the target tilt angle. When the real-time tilt angle and the target tilt angle are less than the allowable error value, the controller sends a stop rotation signal to the angle adjustment element. When the real-time tilt angle and the target tilt angle are greater than the allowable error value, the controller sends an error correction drive signal to the angle adjustment element until the real-time tilt angle and the target tilt angle are less than the allowable error value.

4. The variable frequency tuned liquid damper according to any one of claims 1 to 3, characterized in that, The control unit includes a controller, a driver, and an encoder. The controller sends an angle adjustment command based on the difference between the real-time tilt angle and the target tilt angle. The driver converts the angle adjustment command into voltage and current signals to drive the angle adjustment component. The encoder provides real-time feedback on the real-time angle of the angle adjustment component.

5. The variable frequency tuned liquid damper according to any one of claims 1 to 3, characterized in that, It also includes an adjustment base and a connector. The angle adjustment component is connected to the controlled structure through the adjustment base, and the drive end of the angle adjustment component is connected to the bottom of the closed container through the connector.

6. The variable frequency tuned liquid damper according to any one of claims 1 to 3, characterized in that, The angle adjustment component is a drive motor, the control unit is a motor control unit, and the drive motor is connected to the motor control unit via a cable.

7. The variable frequency tuned liquid damper according to any one of claims 1 to 3, characterized in that, The tilt angle of the closed container can be adjusted from 0° to 90°.

8. A frequency modulation control method for a variable frequency tuned liquid damper according to any one of claims 1 to 7, characterized in that, Includes the following steps: Step 1) Real-time detection of changes in the vibration frequency of the structure. When a change in the vibration frequency of the structure is detected, the tuning frequency of the damper is detected. Step 2) Calculate the target tilt angle of the closed container based on the damper's tuning frequency, the effective side length of the liquid surface along the external load direction in the horizontal state of the closed container, and the average water depth of the liquid surface in the tilted state of the closed container. Step 3) Drive the closed container to rotate to the target tilt angle by adjusting the angle adjustment component, so as to change the effective side length of the free liquid surface of the damping fluid in the direction of external load and realize the dynamic adjustment of the tuning frequency.

9. The frequency modulation control method according to claim 8, characterized in that, In step 2), the target tilt angle is obtained according to the following formula: L c =L / cosα in, This is the tuning frequency of the damper. This refers to the effective side length of the liquid surface along the direction of the external load when the closed container is tilted. The average water depth is the liquid level when the closed container is tilted. Let L be the acceleration due to gravity, L be the effective side length of the liquid surface along the direction of the external load in a horizontal state, and α be the tilt angle of the closed container in an inclined state.

10. The frequency modulation control method according to claim 9, characterized in that, In step 3), the real-time tilt angle of the closed container is detected by the angle detection device. The controller compares the real-time tilt angle with the target tilt angle. When the real-time tilt angle is less than the target tilt angle, the controller sends a stop rotation signal to the angle adjustment device. When the real-time tilt angle is greater than the target tilt angle, the controller sends an error correction drive signal to the angle adjustment device until the real-time tilt angle is less than the target tilt angle.

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