RU2797354C1 - Insulation of the armature winding of a dc locomotive traction motor - Google Patents

Abstract

FIELD: electric engineering.

SUBSTANCE: invention relates to the design of the insulation of the armature winding of DC traction motors. The armature of the DC locomotive traction motor contains the grooved part of the armature, the conductive part of the armature winding and the turn insulation covering it. At the same time, the current-conducting part of the armature winding is covered by coaxial cylindrical heat-shrinkable polymer shells. Moreover, the coefficient of linear thermal expansion of the inner shell is equal to the coefficient of linear expansion of the conductors of the conductive part of the armature winding, and the outer shell is equal to the material of the slot part of the armature.

EFFECT: increasing the durability of the insulation of the anchor winding of the locomotive DC traction motor.

1 cl, 1 dwg

Description

The field of technology to which the invention belongs

The present invention relates to the field of electrical engineering and can be used in the insulation of the armature winding of a DC locomotive traction motor.

State of the art

The design of the anchor winding of a DC locomotive traction motor is known (Grishchenko A.V., Kazachenko E.V. New electric machines of locomotives. Textbook for universities of railway transport. - M .: GOU Educational and methodological center for education in railway transport, 2008. - P.64, Figure 1.35), which consists of the slot part of the armature, the current-conducting winding of the armature, covering its turn, body, cover insulation. The most damaged part of the insulation is the coiled one, rigidly connected to the current-carrying part of the armature winding, due to the difference in their linear thermal expansion coefficients (for example, the coefficient for mica-containing coil insulation is 3⋅10 ^-6 °С ^-1 , the coefficient for a copper conductive winding is 16 ,6⋅10 ^-6 °С ^-1 ), that is, their values differ by more than 5 times. Damage to the turn insulation leads to the appearance of conductive bridges in it, along which the breakdown of electrical insulation occurs, which leads to failures of the traction motor in operation.

Disclosure of invention

The objective of the invention is to develop a design that eliminates the occurrence of insulation breakdowns, increase durability and reduce the cost of manufacturing the anchor winding, which will increase the reliability of the locomotive DC traction motor in operation.

The task is achieved by the fact that the current-conducting part of the armature winding is covered by coaxial polymer heat-shrinkable shells. After that, a sequential heat treatment of the structure with a stream of hot air is performed, as a result of which a reliable connection of the obtained insulation with the armature winding section is achieved. In this case, the material of such polymer shells should be selected from the condition that the coefficient of linear thermal expansion of the inner shell is adequate to the coefficient of linear thermal expansion of the conductors of the armature winding, and the outer shell - to the material of the groove part of the armature.

Brief description of the drawings

In FIG. 1 shows the slotted part of the armature winding.

In FIG. 1:

1 - slot part of the anchor winding with a current-carrying part;

2 - coiled insulation;

3, 4 - inner and outer shells in the anchor core;

5 - anchor;

6 - wedge.

Implementation of the invention

The construction works as follows. When current passes through the current-carrying part of the armature winding, it heats up and thermally lengthens (according to the Joule-Lenz law). Due to the fact that the coefficient of linear thermal expansion of the inner polymer shell is adequate to the coefficient of linear expansion of the conductors of the conductive part of the armature winding, and the outer shell - to the material of the slot part of the armature. In this case, the elongation of the components of the insulating structure will be adequate for the corresponding contacting parts of the armature.

The technical and economic advantage of the described solution in comparison with the known ones is that the proposed design eliminates the occurrence of insulation breakdowns, increases durability and reduces the cost of manufacturing the armature winding, which will increase the reliability of the locomotive DC traction motor in operation.

Claims (1)

An armature of a DC locomotive traction motor, comprising a grooved part of the armature, a conductive part of the armature winding and a coil insulation covering it, characterized in that the conductive part of the anchor winding is covered by coaxial cylindrical heat-shrinkable polymer shells, and the coefficient of linear thermal expansion of the inner shell is equal to the coefficient of linear expansion of the conductors of the conductive part of the armature winding, and the outer shell - to the material of the slot part of the armature.

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