A kind of wind-driven generator tower frame shock absorbing device and design method
Technical field
The present invention relates to a kind of wind-driven generator tower frame shock absorbing device and design method, belong to wind-driven generator safe operation supporting technology category.
Technical background
Modern overhead facility is increasing, in order to prevent that vibration that external factors such as wind-force, earthquake cause and generalized resonance are to the destruction of high-rise facility, the occasion of having ready conditions and outside damping being set or reinforcing condition at majority, all increase the annexes such as drag-line of peripheral hardware, commonly the earth is added the drag-line that tiltedly draws from its high-end all directions, as high reaction tower and electric power transfer pylon or the electric pole etc. of Ferrous Metallurgy, petrochemical industry, all be annexes such as drag-line by the peripheral hardware stability that increases them.Yet, also have some facilities but can not add above-mentioned vibration damping equipment.As the urban skyscraper thing, particularly have certain altitude, be in the wind-driven generator that has in the wind environment for a long time again, more can't adopt abovementioned technology to solve stable problem.For wind motor, the cabin assembly that constitutes its main quality by towering pylon independent support in the high-altitude, not only environment badly (is selected to be installed in the high wind environment in order to generating) especially, present center of gravity height, pylon rigidity is low, resonant frequency is low feature, and be subjected to the direct effect that goes round and begins again of the excitation force of wind-driven generator wheel rotor; In addition, because the radius of high-altitude impeller is slightly less than the pylon height, impeller must be followed the trail of changeable wind direction again and may can not adopt the technical measures that drag-line and so on externally is set to obtain damping towards any direction at all, because it must hinder impeller safety.
Wind motor is in above-mentioned technical specifications and working environment just, there are major accidents such as the loosening fracture of pylon attachment bolt, pylon collapse to take place in the time of consequently, cause the loss of the up to ten million units of every example, restricting human energy strategy target for realization reduction of discharging, low-carbon (LC), environmental protection and carrying out the progress of wind energy development.
In order to reduce the particularly pylon damaging vibration that produces because of wind of wind-driven generator of overhead equipment, existing disclosed technical solution is as follows:
One; the tower top that is formed by connecting by the circular tower tube of multistage at wind-driven generator; be positioned at the below, cabin of wind-driven generator, place tens of tons sandbag, the grains of sand or sandbag move mutually and produce when trying hard to utilize vibration friction consumption vibrational energy, reduction vibration.Practical application shows: poor effect, because all grains of sand are along with cat head is synchronized with the movement and rare relative movement.
Its two, the high-rise tower tube that supports wind-driven generator is made interlayer, and between interlayer, fills with sandstone, the friction that sandstone move mutually when trying hard to utilize vibration reduces vibration.Actual effect is also very poor, because all sandstone are along with the tower tube is synchronized with the movement and rare relative movement.
So that used the pylon of above-mentioned vibration reducing measure and equipment that great interruption of service still takes place often.
In addition, in some very few extra-high-speed layer building of the whole world, utilize the height of number floor in this building in the high-altitude, in inside the ACTIVE CONTROL damper that is worth tens million of units is installed, by measuring the vibrations in wind direction, wind-force, building, is calculated by computer, send instruction, control hydraulic pressure or pneumatic shuttle, reversing motion is done to hundreds of tons the weight of installing in the building relatively, reaches the vibration that the external force of contending with causes.Though this technology can make the vibration in building reduce about about 50%.But its cost and effect all can not be accepted by the wind-driven generator field.
In existing high-rise pylon damping technology scheme: propose to hang one and equal the single pendulum pylon resonant frequency, that do not have (or only having minimum) damping and can realize that also pylon carries the vibration damping on the resonant frequency in that pylon is high-end.But the pylon amplitude of the amplitude of single pendulum when not increasing single pendulum is bigger, can't be in the space limited inner use of pylon; And owing to the resonant frequency of pylon along with change of wind velocity changes, the single pendulum of fixed frequency but can't be followed the tracks of this frequency and fail, and has more reduced resonant frequency and does not allow because increase with the system behind the single pendulum frequently.
The designer is to wind-driven generator basic structure and running analysis of dynamics according to the present invention, and wind-driven generator easily impaired reason in service is as follows:
The work characteristics of wind-driven generator is different from other static fixed equipment, it not only has the impeller of rotation, because the amount of unbalance of impeller with mechanical structure or pneumatic factor, on-streamly will produce the unbalanced force vertical with rotor shaft direction, cause pylon system generation transverse vibration.The working speed of impeller is often selected 8~20r/min for use, corresponding speed-frequency f
j=0.1333~0.3333Hz, but the speed-frequency scope when starting is 0~0.1333Hz.Because up to a hundred tons the quality of reaching of wind-driven generator mainly concentrates in the cabin on pylon top, and pylon adopts the thin-walled tower tube of steel more, its lateral stiffness is low, so that the natural reonant frequency fg of wind-driven generator tower frame system is very low; In order to prevent pylon system and wheel rotation frequency resonance and reduce cost that the resonant frequency of pylon often is designed to be higher than the highest rotational frequency of impeller, namely is designed to fg=0.35~0.5Hz.But because the resonant frequency of this system is low, particularly can't outside auxiliary damping be set to the earth, so the Q value of its resonance is high especially, resonance is big especially for gain or the amplification factor of once per revolution vibration, so that change of wind velocity, fitful wind, typhoon can both excite, and pylon takes place significantly, decay generalized resonance (free vibration attenuation) very slow, that the endurance is very long.Fatigue, stretching, loosening, fracture taking place just because of the connecting bolt between tower tube, each section of tower tube is subjected to the powerful alternating stress of generalized resonance continually, reduced the lateral stiffness of tower tube, and then reduces the resonant frequency of pylon.Change frequently that scope just resonates in case resonant frequency is reduced to impeller, make the above-mentioned parts of breakage be subjected to extraordinary huge stress and cut off, tear and collapse.
In order to improve the safety index of pylon, the wall thickness of attempting to increase pylon is unpractical to improve resonant frequency, because the damping of this mode of structure is still very low, still keeps away generalized resonance and the destruction thereof of unavoidable high Q value.Have the vibration damping equipment that increases classical damping (but condition restriction and can not realize) or can play damping effect only, can fundamentally overcome this hidden danger.
So a kind of new tower frame shock absorbing device that can overcome the shortcoming of above-mentioned prior art of active demand.
Summary of the invention
Purpose of the present invention: be intended to propose a kind of wind-driven generator tower frame shock absorbing device and design method, in the eminence of pylons such as wind-driven generator near the top, a kind of need not detect wind-force, wind speed, vibration are installed, do not need electronic equipments such as computer, need not consume electric power and can realize " the adaptive damping device " of ACTIVE CONTROL, reduce tower oscillation, the safety of protection equipment; Be mainly used in being installed in the inside, pylon top of overhead equipment, solve the difficulty that many overhead equipment can not arrange outside damping vibration attenuation, by absorbing vibration, increase damping, consuming oscillation power, reach and reduce tower oscillation (particularly generalized resonance), prevent the purpose of pylon breakage, collapse accident.
A kind of wind-driven generator tower frame shock absorbing device and design method proposed by the invention, it is characterized in that: it is by a thirtieth to 1/10th damping block of " a blower fan quality " that accounts for wind-driven generator high-altitude engine room facilities, damping block is supported or hangs on the supporting part of pylon top layer relevant position, be installed on the low rate damper that the pylon top layer is realized the damping block damped motion and consumed vibrational energy, constitute the resonant frequency frequency low very low frequency resonator-type that reaches 0.01~0.1Hz, need not detect wind-force, wind speed, vibration, do not need electronic equipments such as computer, need not consume electric power and can realize the adaptive damping device of ACTIVE CONTROL.
The supporting part of described support or hanging vibration reduction piece is for connecting the wire rope between pylon top layer upper plate and the damping block.
The supporting part of described support or hanging vibration reduction piece, be one terminate on the top board and base plate of tower tube top layer, the other end is connected on the wire rope on the damping block; Described rope capacity all with guarantee that damping block is unlikely to drop on the base plate or on throw top board, other original structure that also is unlikely to laterally to clash in pylon and the pylon is as the criterion.
The supporting part of described support or hanging vibration reduction piece, be that an end is hinged on the pylon top layer base plate, the other end is hinged on the pull bar on the damping block, described pull bar length all with guarantee that damping block is unlikely to drop on the base plate or on throw top board, other original structure that also is unlikely to laterally to clash in pylon and the pylon is as the criterion.
The supporting part of described support or hanging vibration reduction piece is that an end is fixed on the base plate, the other end is fixed on the metal-rubber spring on the damping block, and described metal-rubber spring is the assemblying body of supporting part and low rate damper.
The supporting part of described support or hanging vibration reduction piece is one to be installed on damping block below, to be supported on universal rolling device on the pylon top layer base plate through a plurality of rollers by bearing off-centre by back shaft.
The pylon top layer base plate of described universal rolling device bottom is provided with the spacing back-up ring between restriction roller scrollable area.
Described damping block is installed on the described platform-type supporting part universal rolling device, or makes described damping block and described supporting part universal rolling device as a whole.
A kind of wind-driven generator tower frame shock absorbing device and design method are further characterized in that: the resonant frequency (f of vibration damping equipment wherein
0) design method is the resonant frequency (f of vibration damping equipment
0) be lower than the working speed frequency (f of wind-driven generator impeller
j) and the resonant frequency (f of pylon
g);
Its design should be satisfied formula f
0=(K
2/ M
2)
0.5(1-η
2 2)/(2 π),
M
2-be the quality of damping block (1);
K
2-for hanging down the rigidity of rate damper (3-1 and 3-2);
η
2-for hanging down the damping constant of rate damper (3-1 and 3-2).
Described a kind of wind-driven generator tower frame shock absorbing device and design method is characterized in that: because the damping constant (η of machinery
2) be very little a, amount close to 0, described resonant frequency (f
0) simplified formula is f
0≈ (K
2/ M
2)
0.5/ (2 π).
Described a kind of wind-driven generator tower frame shock absorbing device and design method is characterized in that: described resonant frequency f
0=0.01~0.1Hz.
Described a kind of wind-driven generator tower frame shock absorbing device and design method are further characterized in that: in order fully to reduce the resonant frequency (f of vibration damping equipment
0) to close to or equal 0, can the rigidity Design of low rate damper (3) for close to or equal 0, that is: f
0=lim
K2 → 0[(K
2/ M
2)
0.5/ (2 π)]=0.
This wind-driven generator tower frame shock absorbing device and design method according to above vibration damping equipment and design method proposition, under without detecting sensor, without electronic circuit and computer, prerequisite without consumes energy, realization is for the blower fan quality of the high-rise supporting of pylon and the vibration damping of pylon, have speed of response because of do not rely on above-mentioned condition faster, have simply more reliable because of link, have advantages such as the extra power of not relying on is more energy-conservation, cheap and solved the contour controlling way that sets up the pylon fracture that is equipped with, loosening, collapse accident of wind-driven generator reliably.
Description of drawings
Fig. 1 wind-driven generator tower frame shock absorbing device schematic representation;
Mechanical model and the electronics equivalent model of the original blower fan pylon of Fig. 2 system;
Fig. 3 sets up mechanical model and the electronics equivalent model of damping device;
Fig. 4 pylon resonant frequency f1=0.5Hz, vibration damping equipment resonant frequency f2=0.1Hz, the test chart of resonance gain G 1=G2=42.04dB;
Fig. 5 resonant frequency f2=0.1Hz, the low resistance vibration damping equipment of resonance gain G 2=42.04dB is test chart to no effect;
The damping that Fig. 6 increases vibration damping equipment is to 20 times of the pylon damping, the test chart of resonant frequency and resonance gain;
The former pylon of Fig. 7 system is subjected to generalized resonance after the effect of pulse wind-force for up to 200 seconds, and vibration damping equipment does not form the test chart of resonance;
The vibration damping equipment that Fig. 8 increases after the damping is installed to the test chart that tower top has effectiveness in vibration suppression;
Fig. 9 installs the test chart that the big damping device tail tower generalized resonance time was reduced to from 200 seconds 50 seconds;
The vibration damping equipment that Figure 10 increases damping further is reduced to 0 with rigidity, and then response is reduced to-test chart of 1.45dB to the pylon line vibration frequency of 0.5Hz;
The no rigidity shock absorption device that Figure 11 increases damping is installed to the test chart that tower top has effectiveness in vibration suppression;
Figure 12 installs big damping does not have the test chart that the rigidity shock absorption device tail tower generalized resonance time was reduced to from 200 seconds 50 seconds;
Figure 13 is wire rope support device schematic representation;
Figure 14 is metal-rubber spring supporting damping device schematic representation;
Figure 15 is the rolling support device schematic representation;
Among the figure: the supporting part 3-1 that 1-damping block 2-1 and 2-2-supporting part 2-are platform-type and 3-2-hang down rate damper 4-tourelle 5-ring washer 6-metal-rubber spring
Embodiment
The wind-driven generator tower frame shock absorbing device that the present invention introduces, it is by a thirtieth to 1/10th damping block 1 of " a blower fan quality " that accounts for wind-driven generator high-altitude engine room facilities, damping block 1 is supported or hangs on supporting part 2-1 and the 2-2 of tower top, be installed on the pylon top layer and realize damping block 1 damped motion, and low rate damper 3-1 and the 3-2 of consumption vibrational energy, supporting is connected damping block 1 with 2-2 with supporting part 2-1 at the pylon top layer, and the low rate damper 3-1 by being connected the pylon top layer and 3-2 constitute the very low frequency resonator-type vibration damping equipment of 0.01~0.1Hz of correspondence when resonant frequency is low to be reached the wind-driven generator impeller and start the transient process rotating speed and be 0.6~6r/min simultaneously, as shown in Figure 1.
In order to further specify the working principle of this vibration damping equipment, according to the equivalet class ratio method of the mechanical structure-electronic circuit that meets the natural law, the above-mentioned design of wind-driven generator tower frame shock absorbing device is carried out the analogy simulation analysis in following.
The stiffness K of machinery is analogous to the 1/L reciprocal of the inductance L of electronic circuit component; The mass M of machinery is analogous to the capacitor C of electronic circuit component; The damping η of machinery is analogous to the resistance R of electronic circuit component.
If pylon rigidity is K
1, the inductance of analogy is L
1If the blower fan quality is M
1, the electric capacity of analogy is C
1If the damping of machinery is η
1, the resistance of analogy is R
1
The resonant frequency of machinery is: f
0=(K/M)
0.5/ (2 π).(omitting influences one of very little damping to resonant frequency)
The resonant frequency of electronic circuit is: f
0=(1/L/C)
0.5/ (2 π).(omitting influences one of very little resistance to resonant frequency)
So original resonator system of pylon has the equivalent analog model of Fig. 2.
Handicapping Buddhist nun device rigidity is K
2, the inductance of analogy is L
2Handicapping Buddhist nun (damping block) quality is M
2=M
1/ 10, the electric capacity of analogy is C
2=C
1/ 10; If the damping of low rate damper is η
2, the resistance of analogy is R
2So the vibration damping equipment resonator system of setting up has the equivalent analog model of Fig. 3.
If the fan vibration resonant frequency f of original pylon system
1=0.5Hz, the resonant frequency f of vibration damping equipment
2=0.1Hz, under corresponding low resistance condition, their resonance gain is G
1=G
2=42.04dB is as accompanying drawing 4.
This vibration damping equipment is installed to tower top, and then the resonant frequency of fan vibration is constant, and the resonance gain only is reduced to 41.83dB, reduces 0.21dB.As seen: the vibration damping equipment of low resistance does not have effectiveness in vibration suppression.As accompanying drawing 5.
The damping of vibration damping equipment is increased 1000 times, be 1/20 of former pylon system damping, i.e. R
2=R
1/ 10, establish the fan vibration resonant frequency f of original pylon system
1=0.5Hz, the equal G of resonance gain
1=42.04dB, the resonant frequency f of vibration damping equipment
2=0.1Hz, the resonance gain G
2=0dB for the gain of 0.5Hz is-1.34dB, as accompanying drawing 6.Original pylon system is subjected to generalized resonance after the effect of pulse wind-force for up to 200 seconds, and vibration damping equipment does not form resonance.As accompanying drawing 7.
Vibration damping equipment after the increase damping is installed to tower top, and the resonant frequency of fan vibration is constant, and the resonance gain then is reduced to 20.03dB from 42.04dB, has reduced 16dB.As seen: the vibration damping equipment of high damping has effectiveness in vibration suppression.As accompanying drawing 8.Simultaneously, the generalized resonance time of fan vibration was reduced to 50 seconds from original 200 seconds, as accompanying drawing 9.Reduce fatigue and cyclic number and the amplitude of pylon significantly, be conducive to improve fatigue life and the safety index of pylon.
The damping of vibration damping equipment is increased 1000 times, be 1/20 of former pylon system damping, and its rigidity is dropped to 0 (namely cancel inductance L
2), establish the fan vibration resonant frequency f of original pylon system
1=0.5Hz, the equal G of resonance gain
1=42.04dB, the resonant frequency f of vibration damping equipment
2=0Hz, the resonance gain G
2=0dB for the gain of 0.5Hz is-1.45dB, as accompanying drawing 10.
The vibration damping equipment that increases damping and rigidity is reduced to after 0 is installed to tower top, and the resonant frequency of fan vibration is constant, and the resonance gain then is reduced to 21.69dB from 42.04dB, has reduced 15.83dB.As seen: the vibration damping equipment of high damping, no rigidity has effectiveness in vibration suppression.As accompanying drawing 11.Simultaneously, the generalized resonance time of fan vibration was reduced to 50 seconds from original 200 seconds, as Figure 12.
Embodiment 1:
A kind of wind-driven generator tower frame shock absorbing device, its resonant frequency f
0Design method is the working speed frequency f that is lower than the wind-driven generator impeller
jResonant frequency f with pylon
gThe impeller working speed scope of wind-driven generator is generally n
j=8~20r/min, the working speed frequency f
j=0.1333~0.3333Hz, the resonant frequency of pylon is typically designed to f
g=0.35~0.5Hz is for the resonant frequency of realizing vibration damping equipment is lower than f
j, f
g, f for example
0=0.01~0.1Hz, and make the mass M of damping block
2, low rate damper stiffness K
2With damping η
2With resonant frequency f
0Between meet f
0=(K
2/ M
2)
0.5. (1-η
2 2)/(2 π).Because the damping constant η of machinery
2Be very little a, amount close to 0, so following formula can be reduced to f
0=(K
2/ M
2)
0.5(1-η
2 2)/(2 π) ≈ (K
2/ M
2)
0.5/ (2 π).
Damping block 1 can be used the iron and steel manufacturing, in order to reduce cost, and also can be at a steel box house placement of concrete or sandstone.
Because the required activity space of damping block 1 is limited, more owing to should not therefore need the mass M 2 of restriction damping block 1 in the too big quality of tower top increase; Therefore the resonant frequency of the vibration damping equipment that may cause rises, then can be with reducing the stiffness K of hanging down rate damper 3-1 and the damping block 1 of 3-2
2Realize, for example use around tower tube and damping block, is connected, enough big, good elastic extension springs of flexibility of tensile elongation, it has very low tensible rigidity K
2Also can use piston have axial aperture, be filled with gas or oil the vibration damping cylinder or oil cylinder in hinged mode, be connected in around tower tube and the damping block, the cylinder body of this vibration damping gas or oil cylinder and piston rod are connected to tower tube top layer and damping block 1 by hinge respectively, when damping block 1 motion, the fluid of cylinder interior flows by the aperture of piston, generation is to damping and the heating power consumption of motion, but can in the length range of piston rod, stop arbitrarily and do not have elasticity, and stiffness K 2 is close to zero.Elastic and vibration damping (gas or oil) cylinder can be existing product.
Embodiment 2:
In actual applications, this wind-driven generator tower frame shock absorbing device owing to must limit the sphere of activities of damping block 1, is unlikely to clash at the volley pylon; Low rate damper 3-1 and 3-2 owing to need protection, therefore the weight that should not make it to bear damping block 1 must have supporting part 2-1 and the 2-2 that carries damping block 1.The supporting part 2-1 and the 2-2 that meet above-mentioned requirements, can with one terminate on the top board and base plate of pylon top layer, a wire rope that terminates on the damping block 1, the rope capacity that this supporting part is selected for use all should with guarantee that damping block 1 is unlikely to fall volt to base plate or on throw top board, and between described damping block 1 and pylon inwall or pylon top layer top board, pylon top layer base plate, settle low rate damper 3-1,3-21, by the effect of low rate damper, assurance is unlikely to laterally to clash into other original structure in pylon and the pylon.As Figure 13.
Embodiment 3:
In actual applications, this wind-driven generator tower frame shock absorbing device, its supporting part 2-2 can also be fixed on that the other end is fixed on metal-rubber spring 6 damping block 1 below, that lateral stiffness is very low, that damping is very big, that can limit deflection on the top layer base plate with an end, and this metal-rubber spring 6 can be combined into one by a supporting part and a low rate damper and constitute.As accompanying drawing 14.
Embodiment 4:
In actual applications, this wind-driven generator tower frame shock absorbing device, its supporting part can also can be on the top layer base plate be formed the spacing ring washer 5 of 4 of this flatbed tourelles to all directions free rolling flatbed tourelle 4 and with being installed on the base plate with a kind of, damping block 1 is installed on the tourelle 4 by link, as the composite structure of accompanying drawing 15, in addition also can with damping block directly and the flatbed tourelle all-in-one-piece structural type is set.Described tourelle is one to be installed on damping block below, to be supported on universal rolling device on the pylon top layer base plate through a plurality of rollers by bearing off-centre by back shaft.Therefore the conveying mechanism of its underpart can only can not form impact contact and collision to the pylon inwall in interval intrinsic displacement, the rolling set owing to be subjected to being arranged on the restriction of the spacing back-up ring 5 on the pylon top layer floor.