JPS6160662B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flywheel device that converts electrical energy into rotational inertia energy of a flywheel, stores the energy, and releases the energy as electrical energy again when necessary.

FIG. 1 shows a conventional example of this type of flywheel device. In the figure, reference numeral 1 denotes a vertical generator motor, which is fixed on a casing 3 containing a flywheel 2. Reference numerals 4 and 5 denote a stator and a rotor of a generator motor 1, respectively, and a flywheel shaft 2a is connected to the lower end of a rotating shaft 5a via a coupling 6. 7, 8 and 9 are rolling bearings.
The flywheel 2 is held in the casing 3 via rolling bearings 8 and 9. Reference numeral 10 denotes a disc-shaped electromagnet, which is mounted in the casing 3 with its magnetic pole face facing the upper surface of the flywheel 2. This loads most of the weight of the flywheel 2 with the attraction force of the electromagnet 10, reducing the thrust load on the rolling bearings 8 and 9, reducing friction loss in the rolling bearings, and increasing energy conversion efficiency. It is for this purpose. 10a is an excitation winding. Reference numeral 11 denotes a power device that sends and receives electrical energy to and from the generator motor 1 .

In this configuration, energy is stored by driving the generator motor 1 as an electric motor and converting electrical energy from the power device 11 into rotational inertia energy of the flywheel 2, and energy is released by driving the generator motor 1 as an electric motor. This is done by operating the rotational inertia energy as a generator, converting the rotational inertia energy into electrical energy, and returning the electrical energy to the power device 11. This storage and release of energy is generally done relatively instantaneously, and for this reason, a large step-like or impulse-like load torque acts on the rotor of the generator motor 1, causing the flywheel 2 and the flywheel shaft 2a to act on the rotor of the generator motor 1. Transient torsional vibration occurs in the torsional vibration system consisting of the rotor 5 of the generator motor 1 due to the torsional natural frequency of this system, and especially the flywheel shaft 2a
Excessive torsional stress occurs. Moreover, since the conventional structure described above does not include a damper element for this torsional vibration, the torsional vibration becomes continuous and the torsional stress generated in the flywheel shaft 2a becomes a repeated stress of the torsional natural frequency period.

Therefore, when energy storage and release operations are repeated frequently, for example when used to effectively utilize regenerated electric power in a train, fatigue of the flywheel shaft 2a accelerates due to the repetition of the above-mentioned torsional stress. ,
There was a risk that the flywheel shaft 2a would break and the device would be damaged, and reliability and safety were problematic, especially when increasing capacity.

This invention was made in order to eliminate the drawbacks of the conventional ones described above, and by installing an electromagnetic torsion damper at a suitable location on the rotating shaft system of the device,
Reduces flywheel shaft fatigue compared to conventional models,
The purpose of the present invention is to provide a flywheel device that is highly reliable, safe, and provides good rotational performance.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In FIG. 2, reference numeral 12 denotes a disc-shaped rotating body made of a conductive material, and a machine frame 1 of the generator motor 1.
It is fixed to the shaft end of a rotating shaft 5a that projects from a. Reference numeral 13 denotes a flat fixed magnetic yoke, which has vertically opposing magnetic pole surfaces 13a, 13a, and houses an annular excitation winding 14 therein. The fixed magnetic yoke 13 is attached to the machine frame 1a so that the rotating body 12 is sandwiched between magnetic pole faces 13a, 13a with a predetermined gap therebetween. Reference numeral 15 denotes an excitation power source, which receives an energy storage/release operation signal in the power device 11 and supplies an excitation current at a predetermined level to the excitation winding 14 for a certain period of time during the energy storage/release operation. It is configured. 13 to 15 constitute an electromagnetic torsion damper, but its installation location does not have to be above the rotor 5 of the generator motor 1 as shown in the figure, but rather on the rotating shaft of a flywheel device such as the flywheel shaft 2a. It can be installed at an appropriate location in the system.

In this configuration, when an excitation current is supplied from the excitation power supply 15 to the excitation winding 14 during the energy storage/release operation, the fixed magnetic yoke 13 is connected to the rotating body 12 as shown by the broken line in the figure. An amount of intersecting magnetic flux occurs. During energy storage and release operations, as described above, a step-like or impulse-like load torque acts on the rotor 5 of the generator motor 1, causing the torsional vibration system including the rotor 5 to vibrate. The rotating body 12 also vibrates within the yoke 13. When rotational displacement of the rotating body 12 occurs due to this vibration, the amount of interlinked magnetic flux changes during a unit time and eddy current is generated on the surface of the rotating body 12, and the electromagnetic force due to this eddy current and the amount of magnetic flux causes torsional vibration. acts in the direction of suppressing Therefore, as shown in Figure 3,
In this embodiment, the torsional stress generated in the flywheel shaft 2a is rapidly reduced compared to (c) in the conventional example described above. Figure A shows the step-like load torque T.

In addition, with this electromagnetic torsional damper, the excitation current is supplied to perform the torsional damper operation only when energy is stored or released, and the torsional damper does not operate during steady operation, so its power consumption is extremely low.

As described above, according to the present invention, the rotating body is fixed at a proper position on the rotating shaft system, and the magnetic pole face of the fixed magnetic yoke having the excitation winding is opposed to the rotating body, so that vibrational displacement occurs in the rotating body. Since an electromagnetic force is generated between the two to suppress the vibration displacement, the transient torsional vibration that occurs in the torsional vibration system of the device during energy storage and release is rapidly attenuated, and the repeated torsion that occurs in the flywheel shaft is suppressed. Since stress can be reduced, fatigue of the flywheel shaft can be reduced and its lifespan can be significantly extended compared to conventional equipment, greatly improving the rotational performance, safety and reliability of the equipment. This improvement makes it possible to safely increase capacity.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a conventional flywheel device, FIG. 2 is a longitudinal sectional view of an embodiment of the flywheel device according to the present invention, and FIG. 3 is a diagram showing torsional stress characteristics. In the figure, 1... generator motor, 2... flywheel, 2a... flywheel shaft, 5a...
Rotating shaft, 12... Rotating body, 13... Fixed magnetic yoke, 13a... Magnetic pole surface, 14... Excitation winding. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. In a flywheel device in which a generator motor and a flywheel are coupled together, a conductive rotating body and an excitation winding are installed at appropriate positions on the rotating shaft system, and the rotating body is sandwiched between the rotating body and the excitation winding. A flywheel device comprising an electromagnetic torsion damper comprising a fixed magnetic yoke having a magnetic pole surface formed thereon, and energizing the excitation winding for a certain period of time during energy storage and release operations.