RU2298274C1 - Electrical machine rotor - Google Patents

Abstract

FIELD: electrical and electromechanical engineering; large electrical machines such as turbogenerators.

SUBSTANCE: proposed rotor has alignment ring assembled of internal and external rings joined together; several rows of tangential slits are made in one of them so that jumpers between slits of one row are disposed opposite intermediate part of other-row slits. In this case, on one hand provision is made for making one of mentioned rings as flexible insert for alignment ring, for instance by producing it from spring steel; on other hand, rotor shroud rings of large electrical machines can be designed so that single-seat overhanging mechanical design of shroud-ring assembly is actually transformed into double-seat assembly by placing internal ring in the form of flexible insert into mentioned assembly, and vice versa.

EFFECT: enhanced rotor reliability due to additional reduction of alternate stress in vicinity of setting shroud rings on rotor core.

3 cl, 3 dwg

Description

The invention relates to electrical engineering, in particular to the rotors of large electrical machines, for example, turbogenerators.

A rotor of an electric machine is known with a winding fixed in the frontal part by massive metal retaining rings, worn on one side on the end parts of the rotor core by a hot fit, and on the other side, through the centering rings in a Z-shaped cross section, which performs the function of elastic elements. However, this form of elastic elements, providing good flexibility of the retaining assembly in the axial direction, does not provide it with sufficient flexibility in the radial direction [1].

The closest analogue to the prototype of the invention is another known design of the rotor of an electric machine [2] with a two-seat design of the retaining assembly, in which the retaining rings are fixed on the back through the centering rings, with tangential slots, on the end parts of the rotor shaft. However, the use of this invention only reduces the alternating stresses in the area of the retaining rings on the rotor core, arising from the deflection of the rotor shaft during operation of the electric machine and can not always be used according to the strength conditions of the centering ring.

The technical result to which this invention is directed is to increase the reliability of the rotor of an electric machine by additionally reducing alternating stresses in the area where the retaining rings fit onto the rotor core.

Figure 1 shows the rotor of an electric machine containing a massive core (1) with a coil winding (2), mounted in the frontal parts (3) in the radial direction using massive metal retaining rings (4), worn on one side of the end parts of the hot core landing, and the other back through the centering rings (5) with elastic elements (6), on the end parts of the shaft (7) of the rotor. Designations: υ _max. - maximum static deflection of the rotor shaft in the central part of the core.

Figure 2 shows a cross section of the centering ring is made of two hot-connected outer (8) and inner (9) rings, in which two rows of tangentially located slots (10) are made. Positions (11) and (12) indicate the outer surface of the outer ring and the inner surface of the second ring, respectively, on which one of the rows of trough-shaped slots is made.

Figure 3 shows a section along AA of the centering ring, on which only the inner ring is displayed on the outer and inner cylindrical surfaces of which trough-shaped slots are made, limited by jumpers (13).

The bandage unit, which is the most mechanically loaded node of the rotor of an electric machine, holds the frontal parts of the windings mounted on a rotating core in the radial direction from the action of centrifugal forces due to the retaining ring, and in the axial direction from the forces resulting from thermal expansion of the winding using a centering ring.

In the two-seat design of the retaining assembly, with retaining rings fixed on both sides, alternating stresses that occur during operation of the electric machine from the deflection of the rotor shaft in the area of the retaining rings on the core, the value of which reaches its maximum value in the middle part of the rotor (υ _max ). The same stresses arise in the single-seat design of the retainer assembly from the influence of the mass of the retainer ring and the retainer contents during rotation of the rotor.

Eliminate or at least minimize these alternating stresses in the area of the retaining rings on the core of the rotor and are the purpose of the invention.

This is achieved by the fact that the centering ring is made of two outer and inner rings connected by a hot fit, in one of which several rows of tangentially arranged slots are made so that the jumpers between the slots of one row are located opposite the middle part of the slots of the other row. In this case, the opportunity arises, on the one hand, to purposefully perform one of the rings as an elastic insert in the centering ring, for example, having made it from spring steel, and on the other hand, the possibility of a variant constructive solution of the retaining elements of the rotors, for example, the transformation of a single-seat cantilever execution of the retaining node in a two-seat, by installing the insert - the inner elastic ring and vice versa.

Moreover, it seems appropriate to place the tangential slots of at least one of the upper and lower rows of slots on the outer and inner surfaces of one of the rings, intended to become an elastic element in the centering ring, and the slots themselves are made of a trough-like shape. This design of the slots, the closest in shape to the leaf spring, among other things, is much more reliable and easier to manufacture than the elastic elements in the centering ring in the form of closed slots.

In some cases, it is impossible to make elastic elements in the form of trough-shaped slots, for example, according to the strength conditions of the mating components, then when placing tangential slots in the inner ring, the lower row of slots is performed on the inner surface of the trough-like shape, and the remaining rows are in the form of an elongated ellipse .

Information sources

1. Titov V.V. and other turbogenerators. Calculation and design. L .: Energy, 1959, p. 18, fig. 1-10 (b) - 895 p.

2. Copyright certificate for the invention of the USSR "Rotor of an electric machine", No. 792491, 09/01/1980

Claims (3)

1. The rotor of an electric machine containing a massive core with a coil winding mounted in the frontal parts in the radial direction using massive metal retaining rings, worn on one side of the end parts of the core, and the other side on the cylindrical surface of the centering ring, in the cross section of which are made the slots in the tangential direction uniformly around the circumference, and the inner surface of the centering ring is connected to the end parts of the rotor shaft, characterized in that the center The ring is made of two outer and inner rings connected to each other, in one of which several rows of tangential slots are made in such a way that the jumpers between the slots of one row are located opposite the middle part of the slots of the other row. 2. The rotor of an electric machine according to claim 1, characterized in that the tangential slots of at least one of the aforementioned upper or lower rows are made on the outer and inner surfaces of one of the outer or inner rings, while the slots are made of a trough-like shape. 3. The rotor of an electric machine according to claim 1, characterized in that when performing tangential slots in the inner ring, the slots of the lower row are made of a trough-like shape on its inner surface, and the slots of the remaining rows are made in the form of ellipses.

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