JP2003250238A - Dynamo-electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a dynamo-electric machine which can provide an improvement of the cooling performance of the coil ends of the rotor thereof. <P>SOLUTION: Conductors are layered in winding slots 13 of a rotor core 12 and outside the winding slots 13 to form rotor windings 14. A cooling gas is made to flow through sub-slots 13A opened in the bottoms of the winding slots 13 in an axial direction from both the ends of the rotor to cool the rotor windings. Further, looking from the outer peripheral side of the rotor, winding ends are bent into curves formed in the directions of the flow of the cooling gas to cool the winding ends. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary electric machine such as a turbine generator, and more particularly to a cooling structure for a rotor thereof.

[0002]

2. Description of the Related Art A conventional rotating electric machine, particularly a rotor of a turbine generator, is provided with a cooling structure for reducing an increase in winding temperature caused by energizing the winding. As a cooling structure for a rotor winding, for example, as described in Japanese Patent Application Laid-Open No. 9-285052, a winding slot for cooling a winding (winding body) housed in the winding slot is used. It is known that a cooling gas is caused to flow through an axial flow path called a sub slot provided at the bottom of the.

[0003]

However, in the winding portion (winding end portion) extending outside the winding slot of the rotor,
Since the retaining ring is provided on the outer peripheral side, only the natural convection generated in the space between the adjacent windings is used for cooling, and there is a problem that the cooling performance is low.

An object of the present invention is to obtain a rotating electric machine having improved rotor end cooling performance in a rotor of the rotating electric machine.

[0005]

(1) In order to achieve the above-mentioned object, the present invention has windings arranged axially at both sides of a magnetic pole portion of a stator and a rotor core. A wire slot, and a rotor that extends inside the winding slot and outside the winding slot and that is composed of a rotor winding in which conductors and conductor insulating materials are alternately laminated. In a rotary electric machine that cools the rotor winding by flowing a cooling gas from both ends of the rotor into an opening sub-slot, a winding end portion extending outside the winding slot is provided with an outer periphery of the rotor. When viewed from the side, it is formed in a curved shape curved in the flow direction of the cooling gas. With this configuration, the cooling performance of the winding end can be improved. (2) Also
In order to achieve the above object, the present invention provides a stator, a winding slot axially spaced on both sides of a magnetic pole portion of a rotor core, and a winding slot in the winding slot and a winding slot. A rotor that extends outside the slot and that includes a rotor winding in which conductors and conductor insulating materials are alternately laminated; and in a sub-slot that opens at the bottom of the winding slot, axially from both ends of the rotor. In a rotary electric machine that cools the rotor winding by flowing cooling gas to the rotor, the winding end portion extending outside the winding slot is inclined in the cooling gas flow direction when viewed from the outer peripheral side of the rotor. It is formed in a polygonal shape composed of a plurality of linear portions. With this configuration, the cooling performance of the winding end can be improved.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The configuration of a rotary electric machine according to a first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a schematic diagram showing a ventilation cooling structure of a rotor of a rotating electric machine according to a first embodiment of the present invention. Figure 2
[Fig. 3] is a perspective view showing an end portion of a rotor of the rotating electric machine according to the first embodiment of the present invention. FIG. 3 is a developed plan view showing an end portion of the rotor of the rotary electric machine according to the first embodiment of the present invention.

As shown in FIG. 1, a rotating electric machine, particularly a turbine generator, comprises a rotor 10 and a stator 20. The rotor 10 includes a rotor core 12 and a plurality of rotor windings 14. Here, as shown in FIG. 2, a winding slot 13 in which a winding 14 is arranged is axially formed in the rotor core 12. The rotor winding 14 is housed in the winding slot 13. The winding housed in the winding slot 13 is referred to as a winding body. The winding slots 13 are arranged on both sides of the magnetic pole portion of the rotor at intervals on the outer peripheral surface of the rotor body, and the plurality of windings forming the same magnetic pole are arranged concentrically around the magnetic pole. The rotor winding 14 is folded back at both ends of the winding slot 13.
Are also arranged concentrically in an arc shape. Between adjacent windings,
By disposing the spacing piece 18, the winding spacing is kept constant. The rotor windings 14 at both ends of the winding slot 13 are referred to as winding end portions. These windings 14 are formed by stacking a plurality of winding conductors in the radial direction, and an insulating layer is provided between the turns.

When the winding 14 is energized from the outside, an electromagnetic field required for each magnetic pole is generated. The winding wire 14 is firmly fixed to the inside of the winding slot 13 by the wedge 15 in the winding body portion so that the winding wire 14 is not skipped in the outer diameter direction of the winding wire due to the strong centrifugal force due to the rotation of the rotor. Has been done. At the rotor end, as shown in FIG. 1, it is fixed by a cylindrical holding ring 16 provided so as to contact the outer peripheral portion of the winding 14.

By energizing the winding 14 to generate an electromagnetic field, Joule heat is generated in the winding conductor.
The rise in temperature of the rotor winding 14 due to Joule heat shortens the insulation layer and shortens the insulation life. Further, the thermal expansion of the winding conductor due to the temperature rise causes a large strain on the winding and the rotor and causes a rotational vibration. Therefore, the rotor has a cooling structure.

As shown in FIG. 1, fans 17 are provided at both ends of the rotor 10. The cooling gas G1 is circulated in the axial direction as the cooling gases G2 and G3 by the fan 17 to cool the rotor winding 14. As shown in FIG. 2, the bottom of the slot 13 is provided with an axial flow path called a subslot 13A. Therefore, as shown in FIG.
The cooling gas G3 taken into the inside of the rotor 10 by the fan 17 flows in the sub-slot 13A as the cooling gas G4. In addition, as shown in FIG.
A large number of holes 14A serving as radial flow passages are formed in the winding body portion of the above. In addition, as shown in FIG.
5 also has holes 15 corresponding to holes 14A of the rotor winding 14.
A is formed. Therefore, the cooling gas G4 taken into the sub-slot 13A, which is the axial flow path, is cooled by the holes 14A,
The winding body portion of the rotor winding 14 is forcibly cooled by flowing through the radial passage formed by 15A.

On the other hand, a holding ring is provided on the outer peripheral side of the rotor winding 14 at the winding end portion extending outside the winding slot 13 as shown in FIG. At the winding ends, the air warmed by the winding 14 forms a flow G7 by natural convection. In contrast to this flow G7, in the present embodiment, by forming flows G8 and G9 along the arcuate winding end portions, the air flow G7 warmed between the windings at the winding end portions is The flows G8 and G9 are used to forcefully flow out in the direction of the cooling gas G4. When the warmed air between the winding ends flows out, the cooling gas G3 flows between the windings to cool the winding ends.

Here, the cooling structure of the winding end portion according to the present embodiment will be described with reference to FIG. FIG. 3 shows the rotor winding end portion shown in FIG. 2 expanded in the circumferential direction.

As shown in FIG. 3, the winding end portion of the rotor winding 14 according to the present embodiment has a curved shape, specifically, a concentric circular arc shape when viewed from the outer peripheral side of the rotor. On the other hand, the winding 14 'shown by the broken line shows the shape of the conventional winding end portion and has a rectangular shape. Although only one winding end is shown in the related art, a plurality of rectangular windings are actually arranged at equal intervals.

In the present embodiment, the cooling gas G3 that hits the winding end becomes a flow G3 'along the outer peripheral surface of the arc-shaped winding end. Also, between adjacent windings,
Flows G8 and G9 follow the outer peripheral surface of the arc-shaped winding end portion. This is a flow formed by the cooling gas G3 entering the lower surface of the winding end (on the side of the rotor core 12) in FIG. 1 and colliding with the lower surface end 14C of the winding end. Is. Again in FIG. 3, the flow G8, G9
Will carry away the warmed air flow (flow G7 in FIG. 1) toward the rotor core side that is warmed by the adjacent windings, and the cooling gas will flow between the adjacent windings. Cool the winding ends.

In the case of the conventional rectangular winding 14 'as shown by the broken line in FIG. 3, the flow G3 strikes the winding end substantially at a right angle, so that a flow is formed along the outer circumference of the winding. Since it is difficult, the air between the windings can be cooled only by natural convection, and the cooling efficiency is low.

On the other hand, in this embodiment, the inflow amount of the cooling gas between the adjacent windings can be increased and the cooling performance can be improved. According to the result of the simulation, the heat transfer coefficient can be increased to about 5 times that of the conventional one, and the cooling performance can be improved accordingly. Therefore, the output of the turbine generator can be improved, and since the winding temperature can be kept low, dielectric breakdown of the insulating layer between the windings is unlikely to occur, the life of the rotating electric machine can be extended, and the safety of the life can be improved. It is possible to improve the property.

Further, by forming the winding end portion in a curved shape when viewed from the outer peripheral side of the rotor, the conductor length of the winding end portion can be shortened as compared with the conventional case, and the winding end portion can be shortened. The heat generation amount of can be reduced. That is, in the conventional rectangular winding end portion, if the axial length is L1 and the circumferential length is L2, the total length of the winding end portion is 2 · L1 + L2, while In the present embodiment, since the total length of the winding end portion is π · L1, the length of the winding end portion can be made shorter than in the conventional case.

Next, the structure of the rotary electric machine according to the second embodiment of the present invention will be described with reference to FIG. Figure 4
FIG. 7 is a developed plan view showing an end portion of a rotor of a rotary electric machine according to a second embodiment of the present invention. The ventilation cooling structure of the rotor of the rotating electric machine according to the present embodiment is the same as that shown in FIG. 1, and the shape of the end portion of the rotor of the rotating electric machine according to the present embodiment is shown in FIG. It is similar to Also,
1 to 3 indicate the same parts.

In the present embodiment, the winding end portion of the rotor winding 14D is formed in a semi-circular shape when viewed from the outer peripheral side of the rotor. The difference from the one shown in FIG. 3 is that the one shown in FIG. 3 has a perfect circular arc shape, whereas the one shown in FIG. 4 has an elliptical arc shape.

Also in this embodiment, as in the case shown in FIGS. 1 to 3, the cooling gas flowing axially on the inner circumferential side of the winding end portion can easily flow into the space between adjacent windings. It is possible to enhance the cooling effect of the winding end portion. Further, as compared with that shown in FIG. 3, the conductor length at the winding end can be shortened, and the amount of heat generation at the winding end can be reduced.

Next, the structure of the rotating electric machine according to the third embodiment of the present invention will be described with reference to FIG. Figure 5
FIG. 9 is a developed plan view showing an end portion of a rotor of a rotary electric machine according to a third embodiment of the present invention. The ventilation cooling structure of the rotor of the rotating electric machine according to the present embodiment is the same as that shown in FIG. 1, and the shape of the end portion of the rotor of the rotating electric machine according to the present embodiment is shown in FIG. It is similar to Also,
1 to 4 indicate the same parts.

In the present embodiment, the winding end portion of the rotor winding 14E is formed in a polygonal shape consisting of only a plurality of straight lines when viewed from the outer peripheral side of the rotor. Since the surface of the winding end portion which is in contact with the cooling gas is inclined in the flow direction of the cooling gas G3 with respect to the flow of the cooling gas G3, the cooling gas G3 which is in contact with the winding end portion is an inclined straight line portion. The flow is along the outer peripheral surface.

Therefore, also in this embodiment, as in the case shown in FIGS. 1 to 4, the cooling gas flowing axially on the inner circumferential side of the winding at the winding end flows into the space between the adjacent windings. Easy to do,
The cooling effect of the winding ends can be enhanced.

Further, by forming the winding end portion into a polygonal shape composed of only a plurality of straight lines when viewed from the outer peripheral side of the rotor,
The conductor length at the winding end can be shortened as compared with the conventional case, and the amount of heat generation at the winding end can be reduced.

Next, the structure of the rotating electric machine according to the fourth embodiment of the present invention will be described with reference to FIG. Figure 6
FIG. 11 is a developed plan view showing an end portion of a rotor of a rotary electric machine according to a fourth embodiment of the present invention. The ventilation cooling structure of the rotor of the rotating electric machine according to the present embodiment is the same as that shown in FIG. 1, and the shape of the end portion of the rotor of the rotating electric machine according to the present embodiment is shown in FIG. It is similar to Also,
1 to 5 indicate the same parts.

In the present embodiment, the winding end portion of the rotor winding 14F is formed in a polygonal shape consisting of only a plurality of straight lines when viewed from the outer peripheral side of the rotor. What is different from that shown in FIG. 5 is that a portion 14F1 orthogonal to the axial direction of the rotor is provided at the center of the winding end portion. as a result,
The one in FIG. 5 has three bent portions, while the one in FIG. 6 has four bent portions. Therefore, although the number of bending steps is increased by one step, the groove formed in the spacing piece 18B for holding the adjacent windings at a predetermined spacing has the orthogonal portion 1
Since the parallel grooves matching 4F1 are enough, it is not necessary to provide a groove for accommodating the "V" -shaped winding as shown in FIG. 5 in the spacing piece 18A, so that the spacing piece can be easily processed. become.

Also in this embodiment, as in the case shown in FIGS. 1 to 5, the cooling gas flowing axially on the inner circumference side of the winding end portion can easily flow into the space between adjacent windings. It is possible to enhance the cooling effect of the winding end portion.

Further, by forming the winding end portion into a polygonal shape composed of only a plurality of straight lines when viewed from the outer peripheral side of the rotor,
The conductor length at the winding end can be shortened as compared with the conventional case, and the amount of heat generation at the winding end can be reduced.

[0029]

According to the present invention, in the rotor of a rotary electric machine, the cooling performance of the winding end can be improved.

[Brief description of drawings]

FIG. 1 is a schematic view showing a ventilation cooling structure for a rotor of a rotating electric machine according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing an end portion of the rotor of the rotary electric machine according to the first embodiment of the present invention.

FIG. 3 is a developed plan view showing an end portion of the rotor of the rotary electric machine according to the first embodiment of the present invention.

FIG. 4 is a developed plan view showing an end portion of a rotor of a rotary electric machine according to a second embodiment of the present invention.

FIG. 5 is a developed plan view showing an end portion of a rotor of a rotating electric machine according to a third embodiment of the present invention.

FIG. 6 is a developed plan view showing an end portion of a rotor of a rotary electric machine according to a fourth embodiment of the present invention.

[Explanation of symbols]

10 ... rotor 12 ... Rotor core 13 ... Winding slot 13A ... subslot 14 ... Rotor winding 14A ... Radial flow path 15 ... wedge 16 ... Retaining ring 17 ... fan 18 ... Spacing piece G ... Cooling gas

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masayuki Kaiho             502 Kintatemachi, Tsuchiura City, Ibaraki Japan             Tate Seisakusho Mechanical Research Center (72) Inventor Kenichi Hattori             3-1-1 Sachimachi, Hitachi City, Ibaraki Prefecture Stock Association             Hitachi, Ltd. Electric Systems Division (72) Inventor Keiji Kobashi             2-12-1 Omika-cho, Hitachi-shi, Ibaraki Prefecture             Ceremony Company Hitachi, Ltd. F-term (reference) 5H603 AA12 BB02 BB12 CA02 CA04                       CB01 CC12 CC15 CC17 CD01                       CD28 CD31 CD32 CE07 CE13                       EE08 EE12                 5H609 BB04 BB18 BB20 PP02 PP06                       PP09 QQ02 QQ09 RR07 RR10                       RR27 RR36 RR37 RR60 RR61                       RR73 RR75

Claims (2)

[Claims] 1. A stator, a winding slot axially spaced on both sides of a magnetic pole portion of a rotor core, and extending inside and outside the winding slot. A rotor comprising a rotor winding in which conductors and conductor insulating materials are alternately laminated, and a cooling gas is axially flowed from both ends of the rotor into a sub-slot opened at the bottom of the winding slot. In the rotating electric machine for cooling the rotor winding, the winding end portion extending outside the winding slot is formed in a curved shape curved in the cooling gas flow direction when viewed from the outer peripheral side of the rotor. A rotating electric machine characterized by. 2. A stator, a winding slot axially arranged on both sides of a magnetic pole portion of a rotor core, and extending inside and outside the winding slot, A rotor comprising a rotor winding in which conductors and conductor insulating materials are alternately laminated, and a cooling gas is axially flowed from both ends of the rotor into a sub-slot opened at the bottom of the winding slot. In the rotating electric machine for cooling the rotor winding, the winding end portion extending outside the winding slot is composed of a plurality of straight line portions inclined in the cooling gas flow direction when viewed from the outer peripheral side of the rotor. A rotating electric machine characterized by being formed in a polygonal shape.