CN1421581A - Tunable power consumption quality damper for power generator - Google Patents

Abstract

The invention is a TMD device using a generator as a damper. It is composed of TMD mass, generator damper and spring group. The generator is connected to the mass of the TMD through rack and pinion meshing, so that the mass drives the generator to generate electricity and consume energy to form damping when vibrating. Changing the external load resistance can easily change the damping coefficient. There are two sets of springs connected to both ends of the mass of the TMD. The selection of the number of springs makes the elastic coefficient of the TMD (or the natural vibration frequency of the TMD) easily adjustable, and the pre-tensioned differential connection is conducive to spring positioning and improved linearity. The device is installed on the top of the high-rise building, and the damping coefficient is set at the optimum value, so that the wind resistance and earthquake resistance of the high-rise building can achieve the best effect, and can maintain long-term stability.

Description

Generator Energy Dissipation Tunable Mass Damper

technical field

The invention belongs to the technical field of building construction, and in particular relates to a generator energy-consuming tunable mass damper (TMD) capable of controlling the vibration of a high-rise building or a towering structure.

Background technique

In recent years, with the advancement of technology, a large number of high-strength and light-weight building materials have been used. Buildings have become taller and taller, and the structure has become softer. At the same time, the damping of the structure has been continuously reduced. Under the action of dynamic loads such as strong winds and earthquakes, high-rise and towering structures will generate relatively strong vibrations, which will not only make users feel uncomfortable, but also easily cause psychological panic. At the same time, excessive vibrations will also lead to failure of building structures and destruction. In order to overcome the defects brought by the design theory, people began to explore a new theory and method, that is, the structural vibration control method.

In traditional structural design, the ability of the structure to resist wind, earthquake and other disasters is generally enhanced by increasing the structural strength, stiffness and ductility. The structural control is to apply a control force to the structure by installing a control mechanism on the structure to reduce the structural vibration caused by external excitation.

Structural vibration control can be divided into passive control, active control and hybrid control. Passive control means that in the absence of external energy supply, the control force is passively generated by the movement or deformation of the device itself when the control device vibrates or deforms with the structure. Active control means that when there is an external energy supply, the control force is actively exerted by the control device using the external energy according to a certain control law. Hybrid control is to apply passive control and active control at the same time in structure, or to apply more than one mode of active and passive control devices at the same time, so that the advantages of various control forms and methods can be fully utilized.

The passive control of the structure does not require energy, the principle and device are relatively simple, it is relatively easy to realize, and the applicability and reliability are good, so it is widely used in civil engineering. Passive control can be divided into three categories: energy absorption and vibration reduction, foundation vibration isolation, and energy consumption and vibration reduction. Energy absorption and vibration reduction are widely used in engineering practice, especially in super high-rise buildings, and can be roughly divided into two categories:

1. Tuned mass damper

A tuned mass damper (Tuned Mass Damper-TMD) is to attach a mass block, spring, and damper to the upper part of the main structure of the building to form a sub-vibration system. After the TMD system is installed on the original main structure, the dynamic characteristics of the structure will change greatly. When the structure is subjected to dynamic loads such as earthquakes and strong winds, the interaction between the TMD and the main structure can realize the transfer of energy from the main structure to the TMD system and consume it, so as to reduce the vibration of the main structure.

2. Tuning the liquid damper

The application of tuned liquid damper (Tuned Liquid Damper-TLD) in structural vibration control began in the 1980s. It uses the adjustment of the liquid damper. During the structural vibration process, the dynamic pressure difference generated by the liquid on the damper box wall is used as the structural control force, so as to reduce the structural vibration during earthquakes or strong winds.

At present, TMD and TLD devices have been used in the John Hancock Building in Boston, the Citicorp Building in New York, the Centerpoint TV Tower in Sydney, Australia, the Toronto TV Tower in Canada, and the wind vibration or earthquake response control of many buildings in Japan. There are also some TV towers and buildings in our country that use TMD, TLD and other devices for structural control. Because TMD, TLD and other devices are generally large in size and often take up a lot of space, in the actual application of TLD, the existing water tank equipment layer of the building is often used as a part of the device.

The theoretical study of TMD proves that there is an optimal TMD damping coefficient. When the TMD damper is adjusted to this value, the building can obtain the most effective vibration reduction effect. If it is greater or less than this value, the vibration reduction effect will be significantly reduced. For this reason, in engineering practice, the parameters of the damper are designed to be adjustable. And the parameters are required to be stable for a long time, which can ensure that the building also has the most effective vibration reduction effect for a long time.

It is relatively easy to realize the designed TMD quality and spring parameters in actual engineering. But it is not so simple to realize a damper whose parameters are stable for a long time and whose parameters are easy to adjust. Therefore, designing a successful damper is often the key to designing a TMD. There are many types of TMD dampers that have been applied in existing engineering practice; electro-hydraulic servo type, hydraulic damping type, etc. Among them, the electro-hydraulic servo type is very effective, the damping coefficient is convenient and adjustable, and it is relatively stable, but it is expensive and requires good maintenance and repair. The damping coefficient of the hydraulic damping type is affected by temperature and oil quality over time, and cannot be stable for a long time, so the best vibration reduction effect cannot be obtained for a long time.

Contents of the invention

The purpose of this invention is to design a novel tuned mass damper (TMD), which has a simple and reliable structure, low cost, convenient and adjustable damping parameters, and stable and reliable performance in a long period of time.

The tuned mass damper (TMD) designed by the present invention is composed of a mass (m), a spring group (k), and a damper (c), and its structural principle diagram is shown in FIG. 1 . Wherein the damper (c) adopts a generator.

The TMD mass (m) of the present invention consists of a sliding frame and an additional mass, the sliding frame is supported by a rolling bearing at the bottom, and a limit bearing is arranged laterally to limit the sliding of the sliding frame.

The TMD spring group of the present invention has two groups of springs, and one end of each group of springs is connected with the sliding frame, and the other end is connected with the spring support on the base plate. The two sets of springs are differentially connected, that is, the installation position of the bracket should ensure that when the sliding frame is still in the neutral position, the springs on both sides are subjected to half of the pretension. The differential connection of the springs can make the sliding frame and the additional mass (m) of the TMD keep the springs in a straight line state during the whole vibration period, and there will be no interference of mutual collision due to the relaxation of the springs, and it also improves the The linearity of the spring. Each group of springs can have several springs, and the elastic coefficient can be adjusted by increasing or decreasing the number of springs.

The TMD generator damper of the present invention is installed under the sliding frame, and a rack is installed at the bottom of the sliding frame, and the rack meshes with the gear of the generator damper to drive the generator rotor to rotate. There is a variable resistor connected to the rotor to adjust the rotor current in order to obtain the best damping. The stator of the generator can be passed with direct current in order to generate a constant magnetic field in the stator.

In the above-mentioned TMD, the generator can be a DC type or an AC type, and the excitation of the stator can be an external source excitation method or a permanent magnet excitation method.

In the present invention, the mass (m) of the TMD, two groups of springs (k) and the damping device (c) of the generator are installed on a metal iron base plate to form a complete TMD.

The working principle of the present invention is as follows:

The TMD mass movement is used to drive the generator to rotate through the rack-and-pinion transmission mechanism, and the stator coil of the generator is supplied with direct current to generate a constant magnetic field. The rotor of the generator generates an induced potential due to the cutting of the magnetic force lines. After an external resistor is connected, a current is generated and energy is consumed at the same time. The current of the rotor receives the damping force under the action of the stator magnetic field; therefore, when the mass of the TMD moves, the mass also receives the damping force from the generator.

The vibration energy of the building under the action of wind or earthquake is transmitted to the vibration of the TMD mass on the top, which makes the generator generate electricity, and the heat energy is quickly consumed on the external resistor, and finally the vibration of the building is greatly attenuated.

The TMD device designed by the present invention is installed on a model of steel structure, and a shaking table test for simulating earthquakes is carried out. The results of the model test show that the vibration control effect of the TMD using the generator damper is obvious for high-rise buildings or high-rise structures.

The advantages of the present invention are as follows:

1. The current in the stator coil of the generator damper and the magnetic field of the stator can be adjusted conveniently by adjusting the DC voltage; in addition, the output current of the generator rotor can also be adjusted conveniently by adjusting the size of the external resistor , so the damping coefficient can be easily set in a large range, and can be set at the optimum value. So that high-rise buildings can achieve the best wind resistance and earthquake resistance.

2. Once the generator damper is installed and adjusted, due to the physical properties of the wire material, resistance material and magnetic material, it will not change for decades. It is not difficult to maintain stable parameters such as the current of the stator coil. Therefore, the time stability of the TMD damping coefficient is very good, and it can be kept unchanged for decades. This ensures that the optimum damping effect of such a TMD arrangement remains unchanged over the long term.

3. TMD adopts multiple springs, which can easily adjust the elastic coefficient by increasing or decreasing the number of springs. The differential connection of the two sets of springs improves the linearity of the springs, and also keeps the springs in the original position when working.

4. The structure is simple and reliable, easy to manufacture, and low in cost. Due to the good stability and no complicated transmission mechanism, there is almost no maintenance. Compared with TMD adopting hydraulic damper and electro-hydraulic servo damper, it saves a lot of manpower and cost.

5. Due to the simple structure and convenient manufacture, the products can be serialized and standardized, especially the generator damper, which can be widely selected from existing generators. If the stator is a generator with permanent magnets, the stator power supply can also be canceled.

6. High-rise buildings and high-rise structures can use the size of the idle space to select TMD products of different sizes to realize the group TMD vibration reduction method, which overcomes the fact that some TMD devices (electro-hydraulic servo TMD) must occupy a large area on the high-rise floor, thereby reducing construction. Insufficient usable area.

Description of drawings

Fig. 1 is a schematic diagram of the TMD principle of the present invention.

Fig. 2 is a schematic diagram of the TMD structure of the present invention. Wherein Fig. 2 (a) is a side view, Fig. 2 (b) is a plane view.

Labels in the figure: M-equivalent mass of building; K-equivalent spring of building; C-equivalent damping of building;

1 is TMD mass, 2 is TMD spring group, 3 is TMD damping, 4 is rack, 5 is generator, 6 is guide wheel (rolling bearing), 7 is TMD spring connection bracket, 8 is limit bearing, 9 is sliding Frame, 10 is gear.

Detailed ways

Below by embodiment, further describe the present invention.

Embodiment: The quality of the TMD is mainly the quality of the frame, and additional quality can be added as needed. The frame 9 is welded into a rectangular frame with 50*50 angle steel, and the middle part is welded with an additional mass bracket and a connecting bracket of the spring group. All these moving parts, together with the added mass, make up the mass (m) of the TMD, a total of 160 kg. A total of 10 rolling bearings 6 with an outer diameter of 50 mm are supported on both sides of the frame bottom. In order to prevent the frame from shaking left and right when vibrating, 6 outer diameters of 50 mm limit bearings 8 are provided on both sides of the frame. According to the mass requirements of TMD design, the additional mass consists of 10kg iron plates.

The spring length of the spring 2 of TMD is 320 millimeters, outer warp is 20 millimeters, has 92, is divided into two groups, and every group one end is connected on the rectangular frame 9, and the other end is connected on the floor spring support 7.

TMD's generator damper 5 is a DC motor with a power of 500 watts and a speed of 2400 rpm, and the stator is powered by a DC power supply, 2.5A. The external resistance of the rotor is a 0-50 ohm enamel sliding wire resistor. Rotor directly connects gear 10, and the number of teeth of gear is 30, modulus is 1.25, and rack 4 length is 750 millimeters, and width is 18 millimeters, and gear 10 is directly meshed with rack 4.

The above-mentioned components are all installed on a 2000mm*2000mm steel base plate with a thickness of 10mm to form a complete set of TMD.

The entire TMD device is installed on a steel structure frame welded by small section steel. The steel frame has an overall size of 2000mm*2000mm*6000mm and is divided into 3 layers. The entire steel frame, together with the TMD device, was installed on a shaking table to simulate various earthquake tests. The test proves that the damping effect of the displacement of the top floor reaches about 40%.

Claims (6)

1, a kind of tuned mass damper is constituted by quality (m), groups of springs (k), damper (c), it is characterized in that damper (c) adopts a generator.

2, tuned mass damper according to claim 1 is characterized in that quality (m) is made up of sliding frame and additional mass, and sliding frame is by the roller bearings of bottom, and laterally disposed have a Limit Bearing.

3, tuned mass damper according to claim 1 is characterized in that groups of springs (k) is two groups of springs, and an end of every group of spring links to each other with sliding frame, and the other end links to each other with spring support on the base plate, and two groups of springs become differential connection.

4, tuned mass damper according to claim 3 is characterized in that the coefficient of elasticity of spring is regulated by the number that increases and decreases every group of spring.

5, tuned mass damper according to claim 1 is characterized in that generator is installed on below the sliding frame, and the sliding frame bottom is equipped with a toothed rack, and the gears engaged of this tooth bar and motor damper drives generator amature and rotates; Rotor is circumscribed with a variable resistor that is used to regulate rotor current.

6, tuned mass damper according to claim 5 is characterized in that generator can be once-through type or AC type, and stator excitation is external source excitation mode or permanent magnet excitation mode.