Background technology
Flywheel energy storage system makes it become the substitute of storage battery and capacitor aspect power storage because of its potential advantage.Compare storage battery and capacitor, the advantage of flywheel energy storage system is: the life-span is long, maintenance period is long and efficient is high.Flywheel energy storage system is that the form of energy with kinetic energy is stored in the flywheel of rotation.Motor drags flywheel and quickens rotation with stored energy, and the rotation of flywheel drawing generator then is converted into electric energy to kinetic energy.Varied permanent magnet excitation and the electromagnetism excitation of comprising of the design of motor and generator, every kind of design all has separately advantage in its use occasion.The structure of fly wheel system and material requested type are varied, comprise steel and carbon fibre composite, and carbon fibre composite can make flywheel with higher speed rotation.Provide support by low-loss, long-life bearing arrangement during the flywheel rotation.In order to reduce the air drag that produces when flywheel rotates, usually flywheel is placed in the vacuum tank of sealing.Although have multiple mode can support flying wheel rotation, as a kind of novel flywheel energy storage system, it not only can the long-life, high efficiency high speed rotating, but also can operate steadily reliably, loss is low.
Summary of the invention
Technical problem to be solved in the utility model provides a flywheel energy storage system that is supported by long-life, high efficiency and low-loss support system.
The technical scheme that its technical problem that solves the utility model adopts is: a kind of flywheel energy storage system with double rigid shafts, and its structure comprises: vacuum tank, the motor/generator system that is used to when being arranged side by side by the in addition fixedly connected fly wheel system of aluminum pipe, the vertical bearing arrangement that is installed in support flying wheel rotation in the container, flywheel stored energy by two disks up and down to quicken and is used to slow down when releasing energy; Vertically bearing arrangement comprises the axial magnetic supporting mechanism of support flying wheel gravity and two rotating shaft mechanisms of control flywheel rotating shaft; Flywheel is connected in the mechanical bearing of top and bottom by upper and lower flexible shaft; When normal operation, flexible shaft has a low bending rigidity, can produce a higher bending rigidity when flexible shaft departs from above certain threshold value.
Particularly: described rotating shaft mechanism comprises and the concentric flexible shaft of fixedlying connected of flywheel, fixedly connected by minor axis between flexible shaft and the flywheel, the external part of flexible shaft links to each other with ball bearing in being fixedly installed on vacuum tank, outer periphery at flexible shaft is equipped with sleeve, sleeve set is provided with radial clearance between the opening of sleeve and the flexible shaft on minor axis.
Described axial magnetic supporting mechanism is made up of the fixed magnet of mutual repulsion and the rotary magnet on the flywheel.
Described motor/generator system comprises the coreless armature of fixedlying connected with vacuum tank and is fixedly installed in the last magnet array and the lower magnet array of the axial alternating polarity on the flywheel card circumference, and coreless armature extend in the gap between magnet array and the lower magnet array.
Described two disk interference up and down are connected to aluminum pipe.
Described vacuum tank is welded by top end cover, bottom head covers and drum.
Vertically bearing arrangement can adopt the mechanical bearing with small-sized rolling element to reduce loss, prolongs lubricant life in order to obtain good thermal conductivity and can also adopt hard-wired bearing.Fly wheel system can carry out overcritical operation under the little situation of the radial load of bearing and axial load.In order to reach supercritical speed, this patent can make fly wheel system smoothness when quickening cross resonance state.
The last lower shaft of fly wheel system is connecting the flywheel upper and lower surface respectively and is being arranged in the rolling element of the mechanical bearing of container top and bottom.Magnetic bearing is carrying the axial weight of flywheel.Flywheel can produce a very little bending rigidity on the axle when normal rotation, when the deflection angle of axle surpasses certain threshold value, can produce a bigger bending rigidity on the axle.Therefore, flywheel has a low critical speed to be called first critical speed, and this critical speed is relevant to its radial support when hanging down rigidity with flywheel mass and axle.In the flywheel accelerator, flywheel will pass through this critical speed.Low critical speed can produce a correspondingly active force inhibition resonance during resonating.When arriving first critical speed, the deflection angle of axle will reach threshold value, and it is big that the rigidity of axle also and then becomes.When first critical speed, the axle higher stiffness limits its radial displacement.In case the rotating speed of flywheel surpasses first critical speed, the deflection angle of flywheel shaft will be reduced in the threshold range, and flywheel will be automatically around its mass centre's rotation, and the rigidity of axle also drops to original low rigidity.Because the deflection angle of flywheel shaft does not surpass second threshold value, so its rotating speed can not reach second critical speed relevant with the axle rigidity of flywheel mass and Geng Gao, when second threshold value, the rigidity of axle will reach second rigidity, and the rotating speed of flywheel is higher.Final result be flywheel limited depart from and vibrate under level and smooth accelerate to the supercritical state operation.
Another one advantage of the present utility model is the inhibition of fly wheel system to external vibration.When fly wheel system suffer from horizontal displacement as the vibration or earthquake, the axle second stiffness limits radially departing from of flywheel.Second rigidity that axle produces when departing from threshold value has suppressed the generation of a very large deflection angle to a great extent, otherwise this huge deflection angle will take place when first rigidity.
Because double rigid shafts has limited radial load, magnetic bearing has limited axial load, so the mechanical load on the mechanical bearing rolling element is little, it is very little that the size of these bearings can be done.When the flywheel high-speed cruising, the loss of small size bearing is littler than the loss of large scale bearing.Fly wheel system adopts that bearings system cheaply makes that flywheel can be level and smooth accelerates to high speed rotating and loss is low.Low-loss has reduced the thermal decomposition of mechanical bearing lubricating oil and has prolonged the non-maintaining cycle of system.
Embodiment
The flywheel energy storage system of double rigid shafts as shown in Figure 1, fly wheel system 30 is by flywheel 31 stored energys of rotation.Two steel disks 32,33 are installed on the same aluminum pipe 34 has formed flywheel 31.Flywheel 31 rotates in vacuum tank 35 to reduce air drag.Vacuum tank 35 is by top end cover 36, bottom head covers 3) and drum 38 be welded.Flywheel 31 is quickened by the last magnet array 39 that is fixed on the axial alternating polarity on steel disk 32,33 circumference, lower magnet array 40, forms air-gap field 41 between last magnet array 39, lower magnet array 40.Last magnet array 39, lower magnet array 40 drive magnetic flux and pass through air-gap field 41 back and forth.Stator coreless armature 42 is installed in the air-gap field 41.Electric energy is loaded in coreless armature 42 windings and produces electromagnetic torque flywheel 31 is quickened synchronously.Flywheel 31 is supported by axial magnetic bearing 43 in the axial direction.Magnetic bearing 43 is made up of the fixed magnet 45 of mutual repulsion and the rotary magnet 44 on the flywheel.Flywheel is diametrically by forming perpendicular to the top of flywheel rotating shaft and the flexible shaft 46,47 of bottom.Flexible shaft 46,47 is installed in the ball bearing 48,49 and follows ball bearing 48,49 to rotate together, and the upper and lower end that ball bearing 48,49 is fixed on container covers.Sleeve 50,51 is installed on the minor axis 52,53 of flywheel.Sleeve 50,51 and flexible shaft 46,47 have radial clearance.When the deflection angle of flexible shaft 46,47 equals radial spacing above threshold value, or when flywheel passed through resonance frequency or apply external vibration load, flexible shaft touched sleeve 50,51, so the rigidity of flexible shaft 46,47 has increased.In fly wheel system 30 start-up courses, flywheel 31 quickens rotation.Flywheel 31 accelerates to corresponding first critical speed of first rigidity with its quality and flexible shaft 46,47.In this critical speed, the deflecting angle of flexible shaft 46,47 reaches threshold value.Flywheel 31 continues to quicken, and the deflecting angle of flexible shaft 46,47 is reduced to below the threshold value.Flywheel 31 is around its mass centre's rotation.If the polar moment of inertia of flywheel is greater than its crosswise moment of inertia, this flywheel has only a cylinder critical speed usually so; If the crosswise moment of inertia of flywheel is greater than its polar moment of inertia, this flywheel will have cylinder critical speed and conical surface critical speed simultaneously so.
Described above only is sets forth and illustrates the utility model; those skilled in the art can be under the situation that does not break away from invention thought of the present utility model; the foregoing description is made various modifications or variation; thereby protection range of the present utility model do not limit by the foregoing description, and should be the maximum magnitude that meets the inventive features that claims mention.