JPH0732553B2 - Rotor coil - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a rotor coil, and particularly to a swelling of a ground insulating layer at an end portion of a coil used with an alternating high voltage and a large current,
The present invention relates to a rotor coil having a coil end portion suitable for preventing a gap from being formed between the conductor and a conductor and preventing a cooling effect from being deteriorated.

[Conventional technology]

In a conventional wound-type rotor coil requiring label dislocation, the coil end portion is composed of a combination of insulated wire conductors of the same size both in the iron core slot and the coil end portion. No. 63648 and Kimiko
Even in the case of a structure in which ventilation is cooled along the axial direction of the coil like No. 35-29339, the expansion of the ground insulating layer at the coil end portion was not considered in the structure of the coil itself. Therefore, as described in Japanese Patent Laid-Open No. 61-54837, insert a spacer having a complicated shape so as to secure a ventilation path between adjacent coils, and insulate the coil from the outside to the ground. I tried to suppress the bulge of the layer.

[Problems to be Solved by the Invention] In the above-mentioned conventional technology, no consideration is given to preventing the ground insulating layer from expanding on the coil structure side, and the centrifugal force due to rotation and the coil end portion due to the centrifugal force are not considered. When the coil receives a high compression surface pressure due to the binding that restrains and supports the movement, the insulating layer expands, and finally the insulating layer peels off from the conductor and it is easy to create a void that reduces the cooling effect of the coil.
There is a drawback that voids are easily formed in the ground insulating layer itself. In addition, even if the spacer is inserted into the coil end portion from the outside to compensate for this defect, there is a disadvantage that the insulating layer against the ground expands in the part without the spacer. There is a problem that an expensive spacer having a curved surface must be inserted over the entire length of the end portion.

An object of the present invention is to provide a rotor coil having an end portion of the rotor coil in which a gap is less likely to be generated between the ground insulating layer and the conductor or in the ground insulating layer itself even when subjected to a high compression surface pressure.

[Means for solving problems]

The above object is to join and integrate the solid bar outside the iron core slot where label dislocation is unnecessary, that is, at the coil end portion, to the combination of the insulated wire conductors in the iron core slot, and the cross-section height is the label dislocation portion. This is achieved by having both the inner diameter side and the outer diameter side set so as to be lower than the sectional height of the.

[Action]

By making the coil end part into a solid bar, it becomes a combination of insulated wire conductors in the iron core slot where label dislocation has been applied. Since the compression rigidity increases, the compression dimension in the cross-sectional height direction under the same compression surface pressure becomes small, and the circumferential or lateral swelling of the ground insulating layer is extremely unlikely to occur. At the same time, considering the space factor of the wire insulation of the wire conductor with label dislocation, it is possible to lower the cross-section height of the solid bar joined to the coil end part by that amount of insulation, so that the cross-section The compression dimension in the height direction is reduced, and the lateral expansion of the ground insulating layer can be further suppressed. That is, by suppressing the expansion of the ground insulating layer in the lateral direction, there is no reduction in the heat transfer coefficient due to the voids caused by the expansion, so that the cooling effect can be prevented from decreasing.

Furthermore, by making the cross-section height of the solid bar joined to the coil end part lower than the cross-section height of the label dislocation part in the form in which both the inner diameter side and the outer diameter side are set, it is possible to bind as in the conventional case. It does not require a bending process, and the space for binding can be easily set, and two-stage binding can be done easily.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. The rotor coils 1 and 2 are mounted in the slots of the rotor core 3 and supported by the wedge 6 via the filler 7. As for the end portion outside the slot, the lower rotor coil 2 is arranged on the coil holding ring 5 via the cushioning material 12 and the binding 9
Is wound and supported and restrained. Further, the upper rotor coil 1 is also wound around the bind 10 to be supported and restrained. Bind 9 and
Regarding 10, the insulating layer 11 is provided to protect the coil insulating layer 1c. For example, a three-phase field coil of a wound rotor of a 300 MVA, 400 RPM class high-speed large-capacity variable-speed generator is exposed to a high centrifugal force of about 1000 G at an unrestrained speed of about 140% of the rated speed.

Therefore, in the iron core slot, the centrifugal force of the coil is supported by the wedge 6, but the compression surface pressure received by the coil is maximum at the unrestrained speed where the rotation speed is the maximum, and the surface pressure is about 200% when the rated speed is 100%. %. On the other hand, the coil end is supported and constrained by the multi-layer winding binding, but a force larger than the centrifugal force needs to clamp and constrain the coil end.
The maximum compression surface pressure of 0% or more will be received. In other words, the coil end part usually receives a compression surface pressure of 200% to 100%, and 0% to 100% of the iron core slot part.
It is exposed to the severe condition that the compressive surface pressure is applied. Therefore, as shown in FIG. 1, for the rotor coil 1,
For a plurality of wire conductors 1a insulated due to label dislocation in the slot, both the inner diameter side and the outer diameter side are preliminarily near one end near the end duct 4 intermediate between the slot outlet and the end of the bind 10. The solid bar 1b having a different-diameter cross section that has been processed and molded into a paragraph form is connected to the above-mentioned paragraph end by brazing or welding to be integrated, and then the insulation 1c is formed.

According to the present embodiment, in the 300 MVA, 400 RPM class high-speed large-capacity variable-speed generator, as shown in FIG.
Since the wire insulation that occupies the%, which governs the compression ratio of the coil, is eliminated, the compression ratio of the coil is about 1 / 2.5, and the height is low because there is no wire insulation, that is, there is material insulation. The coil height can be 80% of that.
Therefore, assuming that the shrinkage dimension is 1 for the entire coil, although there is material insulation, it is 1 / 2.5 × 0.8 = 0.
It is possible to make the shrinkage dimension by compression of 32. Therefore, the swelling dimension of the insulating layer of the coil can be about 3/10, and the swelling with respect to the insulation thickness is 20% and is 6%, which is shown in Fig. 3. Thus, it becomes possible to suppress the temperature rise of 116% to 105%.

〔The invention's effect〕

According to the present invention, the compression rigidity of the coil end is enhanced, and the sectional height of the coil end portion is made lower than the sectional height of the label transition portion. Since the lateral expansion of the ground insulating layer at the coil end portion can be suppressed, it is possible to prevent the cooling effect from being lowered due to the lateral expansion of the ground insulating layer.

Further, by adopting the coil end configuration as described above, it is possible to easily perform two-stage binding, reduce the amount of application, reduce the overall size, and reduce various stresses. Occurs.

In addition, since the solid bar has a different diameter cross-section in which both the inner diameter side and the outer diameter side are sectioned, as shown in FIG. Since it can be securely locked to the end duct, there is an additional effect that the assembly is stable.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an assembled state of a rotor coil of a wire-wound rotor according to an embodiment of the present invention, and FIGS. 2 and 3 are graphs for explaining effects of the present invention. 1 ... Rotor coil, 2 ... Rotor coil, 3 ... Rotor core, 4 ... End duct, 5 ... Coil retaining ring, 6
...... Wedge, 7 …… Filler, 8 …… Intermediate layer, 9 ……
Bind, 10 …… Bind, 11 …… Insulating layer, 12 …… Cushioning material.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-63-124738 (JP, A) Actual development Sho-53-62602 (JP, U) Actual public Sho-2-1370 (JP, Y1)

Claims (1)

[Claims] 1. A rotor coil obtained by performing label dislocation of a plurality of core wire in an iron core slot of a wound rotor, wherein an end portion of the coil has a sectional height lower than that of the label dislocation portion. It is formed of a solid bar having a different diameter cross-section in which both the inner diameter side and the outer diameter side are separated, and the solid bar is joined and integrated with the label-transferred strand near the outlet of the iron core slot. A rotor coil characterized in that