JPS59144341A - Treating method of rotary electric machine coil - Google Patents

Abstract

PURPOSE:To manufacture a product having excellent corona characteristic by integrally impregnating a coil and a core of a rotary electric machine with resin, then precuring at a low temperature while preventing the resin flow lost, and subsequently curing the resin at a high temperature. CONSTITUTION:An epoxy resin is integrally impregnated in the coil and core of a rotary electric machine, thereby preventing the resin flow lost, or precuring the resin, for example, at 100-110 deg.C in a furnace while rotating it at 1-3rpm for 6-10hr. The curing of the resin is advanced, and the resin does not flow. Then, the rotation is stopped, the furnance temperature is raised to 130-150 deg.C, subsequently kept in atmosphere for 8-14hr to finish the curing. In this manner, the crack of the resin in the vicinity of the strands can be prevented, and a product having excellent corona characteristic is manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for treating rotating electric machine coils, and relates to an improvement of the so-called integral impregnation system in which the winding wire and the iron core are impregnated with resin and cured as one body. The process usually consists of the following steps (1) to (6). (1) The rice grains are formed into a tortoise-shell shape with enamel, caranium coating, etc. applied to them.

(2) A coil is made by wrapping a film, mica tape, etc. around this wire as interlayer insulation.

(3) Wrap the mica tape around the coil c with ground insulation. (4) Insert the coil with ground insulation into the iron/U, connect it, and insulate the connection part.

(5) This combination of coil and iron core is injected with melon oil in a vacuum tank, and then pressurized to complete the injection.

(6) After completing the injection, heat the resin in a heating furnace for a certain period of time. Curing O The problem with such an integrated immersion method is the heat curing step (6) above, which has conventionally been the following (a).

(The condition of El+1 is taken and the sentence is written.

(a) To prevent the resin from softening and flowing out during heating,
To be cured in a short time.

(b) To achieve this, it is necessary to cause the resin to react in a short period of time, and in other words, to shorten the heating time, it must be heated and cured in a short period of time at a high temperature.

However, with resins such as epoxy resins that have large curing shrinkage when cured by heat, the corona properties of the coil after curing may be insufficient due to the effects of rapid curing shrinkage. In many cases, quality stability was lacking.

When investigating the cause of this, it was found that when epoxy resin or the like is rapidly cured at high temperatures, cracks occur in the resin layer in the coil insulation. In particular, in the case of Ichimiya-immersion type, there are many resin layers around the strands, so many cracks were observed in this area.

- 10,000, the voltage distribution of the coil insulating layer (c) in the ground direction is the first
As shown in the graph of Figure (a), it was found that the particles were concentrated in areas close to the strands. Therefore, resin cracks around the strands can be said to be the biggest cause of corona generation.
b) is a cross-sectional view of the coil to explain the positions 1 to 4 of the insulating layer, which is the horizontal axis of The sword is pointing away from the element 5.

The present invention is based on the above-mentioned concept, improves the heat curing process of the integral impregnation method, ensures prevention of resin leakage, and
The objective is to provide a processing method that has excellent corona properties and does not increase processing time.

The method of processing the rotary electric coil related to the non-invention is as follows (a)
It is cured by the heat curing treatment method of integral immersion #4 based on the idea as shown in ~(d).

(In order to prevent cracking of the resin near (around) the wire, perform pre-curing at a low temperature.

(b) In this case, since the temperature is low, gelation of the resin is naturally delayed. Therefore, there is a risk that the resin will flow out during curing, so 1. Outflow prevention configuration? or rotary curing method.

(CJ Side fat 7 Post-curing is required to completely cure. Therefore, after the pre-curing is completed, raise the temperature and cure for the required time. The time allocation is determined so that the curing process is completed within the conventional curing time.

Hereinafter, misfiring BA will be explained with reference to FIGS. 2 and 3.

<Example> Epoxy @ fat? After immersing the unit in the rotating electric machine coil, 10
1% 3 r,p for 6-10 hours in an oven at 0-110 °C
While rotating at , m, the precuring process progresses.During this time, the reaction of the tI resin progresses, and the resin no longer flows. After that, the rotation was stopped and the furnace temperature was fully automatically raised to 130-150℃, and its 118-14 characteristics were investigated. The frequency of partial discharge occurrence (p-p, s) has increased significantly □However, X in Figure 2
The properties marked are those obtained by curing a pair of shoes at high temperatures for the required time as usual.

2. In the case of the temperature conditions in Example 2 above, the temperature of the object to be treated, that is, the rotating electrical machine coil, varies depending on the size and shape of the object, as shown in the area indicated by diagonal i'i in FIG. 3. This becomes the pattern.

Because of the step-type curing method of pre-curing at a low temperature and post-curing at a high temperature as described above, according to the processing method of the present invention, cracks in the resin layer near the strands were eliminated and the corona properties were significantly improved. . Even during low-temperature pre-curing, measures are taken to prevent resin leakage, such as using a rotary curing method, so there is no problem with resin leakage.
By determining the pre-curing time and post-curing time by understanding the curing pattern specific to each rotary electric machine coil, two-stage curing can be performed within the conventional curing time, and there is no increase in working time.

[Brief explanation of drawings]

FIG. 1(a) is a graph showing the voltage distribution in the ground direction within the coil insulation layer, FIG. 1(b) is a cross-sectional view of the coil showing the coil insulation layer, and FIG. The graph M3 shown in comparison with one technique is a pattern diagram of time and temperature of the rotating electric machine coil in the case according to the present invention. In the drawing, 1 to 4 are insulating layers, 0% made of 5#i strands.
Former Patent Attorney Ishibe (and 1 other person) Figure 1 (Q) Iku, Wataru Tsubaki, 14fLL Figure 2 A (b) Figure 3

Claims (3)

[Claims] (1) After immersing the coil and iron core of a rotating electric machine in resin, the resin is soaked at a relatively low temperature as shown in Figure 9 to prevent the resin from flowing out.
A method for treating a rotating electric machine coil, which is characterized by curing, sealing, and then post-curing at a temperature higher than the curing temperature. (2) A method for treating a coil of a rotating electric machine, as set forth in claim 1, item 2, characterized in that the integrated coil nobber iron tD is precured while being rotated. (3) In claim 1 or 2, @
The immersion resin is epoxy resin, and the pre-curing is 100-110
℃ for 6-10 hours, post-curing at 130-150℃ for 8-1
Processing method for rotating electric machine coils, which is characterized by a 4-hour treatment time