JPH0237265Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rotor structure for an integral water turbine generator.

Fig. 1 shows the entire integrated water turbine generator that has been proposed in the past.A stator core 2 and a stator coil 3 are arranged on the inner circumferential side of an annular frame 1, and these are connected to an intermediate flange 4 and a can. 5, it has a watertight structure. A guide vane 7 is attached to the radially inner side of a flange 6 attached to the frame 1, and a bearing housing 8 is attached to the center of the guide vane 7. A rotating shaft 9 is attached to the bearing housing 8 via a bearing (not shown). An impeller 10 is attached to the rotating shaft 9, a rotor protector 11 is attached to the outer periphery of the impeller 10, and a squirrel cage rotor 12 is further attached to the outer periphery of the rotor protector 11. This squirrel cage rotor 12 faces the aforementioned stator core 2 via a gap, and constitutes a squirrel cage induction machine. In this configuration, by rotating the water wheel, which is the prime mover, and making the slip negative, it becomes an induction generator.

However, in this configuration, a low frequency alternating current (low voltage large current) corresponding to the slip occurs in the end ring 13 of the rotor 12 shown in FIG. The contained iron sand is attracted and stands up around the end ring 13. For this reason, the rotor 12 is
A phenomenon occurred in which iron sand was caught between the can 5 and the can 5, and the can 5 on the outer periphery of the end ring 13 was worn out.

Therefore, the object of the present invention is to provide a rotor structure for an integrated water turbine generator that prevents damage to the can.

In order to achieve this object, the present invention provides a rotor core 14 in a rotor structure of an integrated water turbine generator.
An end ring 13 having an outer diameter smaller than the outer diameter of the rotor core 14 is provided at the axial end of the rotor core 14, and a retaining ring 17 for press-supporting the end ring 13 is provided at the axial end of the end ring 13. An annular non-magnetic material 1 formed in an annular recess formed by the retaining ring 17, the outer periphery of the end ring 13, and the rotor core 14 to have the same outer diameter as the rotor.
9.

An embodiment of the present invention will now be described with reference to FIG. In FIG. 3, the same parts as in FIGS. 1 and 2 are given the same reference numerals. Squirrel cage rotor 1
2, a rotor core 14 is fixed from both ends in the axial direction by rotor clamps 15, and on the outer periphery of the rotor clamps 15 there is an end ring 13 that short-circuits the rotor bar (see FIG. 2, 16). This rotor clamp 1
5 and a retaining ring 17 on the outside of the end ring 13.
is provided. In addition, 18 is a strength tube of the stator.

In such a configuration, the outer periphery of the end ring 13 of the squirrel-cage rotor 12 is uniformly shaved off so as to be depressed from the outer periphery of the rotor 12 to form a concave portion. Then, a semi-cure bind tape is wrapped around the cut-out recess to form a ring 19 made of a non-magnetic material. In this case, strictly speaking, the recess is formed not only on the outer periphery of the end ring 13 but also on a part of the outer periphery of the retaining ring 17 and a part of the outer periphery of the rotor core 14. The concave portion of the rotor core 14 is tapered to eliminate sharp angles so that the core 14 becomes a magnetic path and prevents magnetic flux from concentrating. Therefore, since the portion covered by the non-magnetic material is the entire recessed portion, it becomes not only the end ring 13 but also a part of the retaining ring 7 and the tapered portion of the rotor core 4. When the non-magnetic material is used as a semi-cured bind tape, after curing, the outer periphery is finished and coated using a lathe. In other words, the ring 19 made of a non-magnetic material is formed to have the same outer circumference as the rotor 12. As a result of the above, a ring of non-magnetic material as shown in FIG. 3 was formed.

Therefore, even if there is magnetic flux due to the current flowing through the end ring 13, the magnetic flux in this vicinity is weakened by the increased magnetic resistance in the ring 19 made of non-magnetic material, thereby preventing damage to the rotor 12 and can 5 due to iron sand. can.

As explained in the embodiments above, according to the present invention, since the outer circumference of the non-magnetic ring is finished with the same outer diameter as the rotor outer diameter, the water flow in this part is not disturbed and the magnetic flux is Since the suction is also weakened, the iron sand can easily pass through and prevent damage to the can, etc.
There are almost no restrictions on the dimensions and shape of the rotor, mainly the end ring and rotor bar, and the degree of freedom in design is not impaired, similar to structures that do not use this method. In addition, manufacturing is inexpensive and simple.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of an example of an integrated water turbine generator, Fig. 2 is a partial sectional view mainly showing a conventional squirrel cage rotor, and Fig. 3 is a rotor structure of an integrated water turbine generator according to the present invention. It is a partial sectional view showing an example. In the drawing, 5 is a can, 12 is a squirrel cage rotor, 1
3 is an end ring, and 19 is a ring made of non-magnetic material.

Claims (1)

[Claims for Utility Model Registration] An end ring 13 formed to have an outer diameter smaller than the outer diameter of the rotor core 14 is provided at the end of the rotor core 14 in the axial direction, and a holder that presses and supports the end ring 13 is provided. ring 1
7, and an annular non-magnetic material 1 formed with the same outer diameter as the rotor in an annular recess formed by the retaining ring 17, the outer periphery of the end ring 13, and the rotor core 14.
9. A rotor structure of an integrated water turbine generator, characterized in that the rotor structure is configured by providing a.