JPH059151U - Rotor groove insulation structure - Google Patents

Abstract

(57) [Abstract] [Purpose] To improve the cooling of a cylindrical rotor. [Structure] The cooling efficiency is improved by notching the coil insulation in the portion corresponding to the radial ventilation hole provided so as to partially expand the iron core slot 3 and exposing the coil conductor in this portion. .

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to an insulating structure that enhances a cooling effect of a field coil of a cylindrical rotor of an AC generator.

[0002]

[Prior Art]

 Miniaturization and weight reduction are required to improve the performance of electrical equipment. Especially in the case of high-speed rotors such as AC two-pole machines, miniaturization and weight reduction is a top priority. It is important to improve the cooling performance to reduce the size and weight, but the high-speed rotor has a cylindrical shape, which is disadvantageous in cooling compared to the salient pole structure.

For this reason, various measures have been taken in order to improve the cooling performance. As one of them, as shown in FIG. 2, the coil 2 of the rotor core 1 penetrates the groove bottom of the core slot 3 in the axial direction. There is a structure in which the axial ventilation holes 4 are provided, and the radial ventilation holes 5 are provided in the groove side portion of the iron core slot 3 at appropriate intervals in the axial direction.

More specifically, as shown in FIG. 1B used in the description of the embodiment of the present invention, the bottom of the groove of the iron core slot 3 has a ventilation hole 4 formed narrower than the insertion portion of the coil 2. An insulator 6 such as a glass laminated plate or a glass mica sheet is laid on the bottom of the groove so as to close the ventilation hole 4. Then, two pieces of the insulating plates 7 formed by heat-molding the semi-cylindrical sheet by impregnating the aramid paper with the epoxy resin on the insulator 6 and along the side wall of the iron core slot 3 are formed into an L shape. Pasted on.

The coil 2 is dropped between the insulating plates 7 which are L-shaped semi-cure sheets. In this case, the coil 2 is energized while being clamped in the radial direction by the coil 2 clamping jig to be heat-molded. At the upper end of the coil 2, an insulator 8 under the wedge is placed and a wedge 9 is driven in.

[0006]

[Problems to be solved by the device]

 However, in the structure shown in FIG. 2 and FIG. 1 (b) described above, although the coil 2 is directly cooled by ventilation cooling, slot insulation is provided between the coil 2 and the iron core. Since it is cooled by ventilation, the cooling effect is reduced.

The present invention has been made in view of the above problems, and an object thereof is to provide a groove insulating structure for a rotor, which improves cooling efficiency and reduces the size and weight of a device.

[0008]

[Means for Solving the Problems]

 The present invention, which achieves the above-mentioned object, is provided with an axial ventilation hole penetrating in the axial direction at the bottom of the core slot groove in a cylindrical rotor of an alternator, and along the side of the core slot groove at regular intervals in the axial direction. A radial ventilation hole is provided, the radial ventilation hole is diverged from the axial ventilation hole to communicate with each other, and the insulation on the groove side of the coil in the radial ventilation hole is fixed in the axial direction from the radial ventilation hole end. It is characterized by notches leaving a distance.

[0009]

[Action]

 Since the coil in the radial ventilation hole is exposed and is in direct contact with the cooling air, the coil cooling effect is improved.

[0010]

【Example】

 An embodiment of the present invention will now be described with reference to FIGS. FIG. 1 is a partial view of a field core, where (a) is a plan view of one coil 2, (b) is the same BB cross section as (a) as the conventional structure, and (c). FIG. 7A is a sectional view taken along line CC of FIG. 1 (a) and 1 (c), the structure corresponds to the radial ventilation holes 5 of the insulating plate 7 of the L-shaped sheet and the insulator (see FIG. 1 (b)) 6 of the groove bottom. In this case, the insulator 6 and the insulating plate 7 are attached to the slot groove with an adhesive so as to protrude from the end of the radial ventilation hole or the end of the iron core by a certain distance (for example, 2 mm from the end of the ventilation hole and 10 mm from the end of the iron core).

Therefore, in the manufacture, the groove bottom insulator 6 and the portion of the insulating plate 7 in the radial ventilation hole 5 are cut out and attached to the inside of the slot groove, and the coil conductor 2 is used as an interstage insulation to form a semi-cure mica. Insert the sheet into the slot 3 while sandwiching it. Then, the coil 2 is energized while being clamped by the coil fastener to heat-mold. Then, an epoxy glass laminated plate is mounted as the insulator 8 under the wedge, and the wedge 9 of the epoxy glass laminated plate is driven in.

It is to be noted that, without cutting out the insulating portion 6 of the slot bottom and the insulating plate 7 located at the groove bottom, only the insulating plates 7 of the L-shaped sheet on both sides of the coil 2 are cut out to remove only both sides of the coil. You may put it out. Since the contact area of the cooling air occupies most of the side portion of the coil with respect to the bottom portion of the coil groove, at least the insulating plates 7 on both sides may be cut out.

FIG. 3 is a diagram comparing the cutouts of the insulator 6 and the insulating plate 7 on the groove bottom and the insulating plate 7 on the groove side with a structure in which these cutouts are not provided. The upper temperature value when a constant current was applied to the coil conductor 2 while feeding a constant air flow from No. 4 was measured by the voltage drop method. X indicates the temperature rise value of the coil having no notch, and O indicates the temperature rise value of the coil having the notch. With the notch, the temperature rise is suppressed by about 15 ° C.

[0014]

[Effect of the device]

 As described above, according to the present invention, the coil conductor is directly cooled by at least the radial ventilation hole, the temperature rise is suppressed, the conductor size can be reduced, and the device can be reduced in size and weight. If the size is the same, the capacity will increase.

[Brief description of drawings]

1A is a partial plan view of a field iron core, FIG. 1B is a sectional view taken along line BB of FIG. 1A, and FIG. 1C is a sectional view taken along line CC of FIG.

FIG. 2 is a partial perspective view of a conventional field iron core.

FIG. 3 is a temperature characteristic state diagram of an example and a conventional comparative example.

[Explanation of symbols]

 2 coil 3 iron core slot 4 axial ventilation hole 5 radial ventilation hole 6, 8 insulator 7 insulating plate

Claims (1)

[Claims for utility model registration] [Claim 1] A cylindrical rotor of an AC generator is provided with an axial ventilation hole penetrating in the axial direction of the core slot groove bottom, and is fixed in the axial direction along the side of the core slot groove. Radial ventilation holes are provided at intervals, the radial ventilation holes are branched from the axial ventilation holes to communicate with each other, and insulation of the groove side portion of the coil in the radial ventilation holes is axially extended from the radial ventilation hole end. Rotor groove insulation structure with a notch left behind for a certain distance.