JPS5935543A - Liquid-cooled rotary electric machine - Google Patents

Abstract

PURPOSE:To readily perform a brazing connection work of a multibranch and a joint base tube to an insulating connection tube by arranging the multibranch and joint base tube outside the outer peripheral plate of the stator of a rotary electric machine. CONSTITUTION:A multibranch base tube 2 is installed outside the outer peripheral plate 9 of a stator frame 6. The through hole 10 of the plate 9, through which an insulating connection tube 3 is passed is blocked by a blind plate 11, and sealed by providing a sealing welded part 12. Coolant 7 is supplied through the tube 2 and the tube 3 to a coil 1. Since the base tube and multibranch joint base tube are moved to the outside of a rotary electric machine, the length of the insulating connection tube can be sufficiently obtained, and a brazing connection work of the multibranch and joint base tube to the insulating connection tube can be performed in the wide working space outside the machine.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement in a liquid-cooled rotating electric machine in which a winding conductor of a stator winding is hollow to allow cooling liquid to flow therethrough.

[Technical background of the invention and its problems] Increasing the capacity of a single turbine generator and making the machine smaller and lighter requires accurate analysis of the loss generated by the machine and appropriate selection of materials accordingly. , structural improvements and improvements in cooling technology are being rapidly implemented. Traditionally, thermal power plants in Japan that have turbine generators have relied on seawater as cooling water for steam condensation and as a heat source for steam generation.
Oil, LNG.

Because it is economical to obtain large amounts of energy sources such as coal from overseas countries, the installation locations are often coastal areas. In recent years, there have been calls for the finiteness of oil resources, and a review of coal-fired power generation is being considered. One example in particular is that in some major coal-producing countries, there are cases where state-of-the-art large-capacity turbine generators are installed near coal mines that are more than 100 km inland at right angles to the coastline. Out - [coming. There is no doubt that such cases will become commonplace in the future.

With the above background in mind, a conventional water-cooled turbine generator will be explained with reference to FIGS. 1 and 2. Figure 1 shows the case where the stator core is directly attached to the stator frame.
Figure 2 shows a case where the stator core is attached to the inner cage and this inner cage is attached to the stator frame.

In general, a turbine generator equipped with a stator winding in which the winding conductor is hollow and cooling water flows through the hollow part, has individual windings (1), a multi-branch main pipe (2), and a multi-branch merging main pipe ( Although not shown, there is a pair 17 of the winding (1) on the opposite side of the multi-branch main pipe (2) and has the same structure as the multi-branch main pipe (2),
The insulated connecting pipe (3) connects the multi-branch main pipe (2) below) between the high potential applied to the winding (1) and the ground where the multi-branch main pipe (2) is placed. In addition to considering the high potential difference between the winding (
1) A flexible insulating material (
(There is a product called Teflon hose). Further, the insulation distance increases in proportion to the potential difference generated by the winding (1). For example, single machine output cuff 0
In a 0 MW class large capacity turbine generator, the voltage of the winding (1) is as high as 25 KV, and the corresponding length of the insulated connection pipe (3) is 70011R or more. On the other hand, as explained in the specific example above, the biggest difficulty in constructing a large-capacity thermal power plant in an inland area is the physical size restriction due to tunnels, bridges, etc. on railway roads, and bridges on general roads. There are various transportation constraints such as weight restrictions on road shoulders, etc., and especially in large-capacity machines, as shown in Figure 2, the stator section has a stator core (4) and the windings ( 1) attached to the inner cage (5) and the stator frame (6), each of which is transported separately and assembled within the power plant construction site. In addition, in Figures 1 and 2, arrow (7)
indicates the direction of cooling water flow, (8) indicates the brazed connection, (
9) shows the stator frame outer peripheral plate.

In a large-capacity turbine generator with such a structure, the biggest weakness is the installation and maintenance of the multi-branch main tube (2) described above to supply and discharge cooling water to the winding (1), which has a water-cooled structure. In this case, although not shown, the part of the winding (1) extending outside of the stator core (4) is crowded with supports and connecting copper bands, etc., and it is arranged in a very narrow space. Ensure that the length of the insulated connecting pipe (3) is long enough, or install the multi-branch main pipe (2) in the narrow space inside the machine where it is difficult to work.
The problem lies in how to verify the reliability of the brazed connection (8) between the insulated connection pipe (3) and the insulated connection pipe (3). This also applies to other liquid-cooled rotating electric machines.

[Purpose of the invention]

The present invention provides a highly reliable fluid that can secure a sufficient length of the insulated connecting tube, easily perform multi-branching and brazing connections between the merging main tube, and the insulated connecting tube, and that can be easily verified. The purpose is to provide cold rotating electric machines.

[Summary of the Invention] In the present invention, by arranging the multi-branching and merging bus pipes on the outside of the rotary electric machine stator frame outer circumferential plate, a sufficient length of the insulated connecting pipes is ensured, making it possible to carry out wide work outside the machine. The brazing connection between the multi-branching and merging main pipe and the insulated connecting pipe is made in a location with favorable conditions, thereby facilitating the connection work and verification.

- Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 3 and 4. In these figures, the same parts as in FIGS. 1 and 2 are designated by the same reference numerals, and their explanation will be omitted.

In this embodiment, the multi-branch main pipe (2) is connected to the stator frame (
6) is installed on the outside of the outer peripheral plate (9). Then, the through hole through which the insulating connection pipe (3) passes through the outer circumferential plate (9) is closed with a blind aυ, and a seal weld (121) is further provided to seal it.

Although not shown in the drawings, this conger eel is of an inner cage type, and during transportation, the insulated connecting tube (3) is bent toward the center by utilizing its flexibility as shown in FIG. 4. or,
The illustration of the diverging and merging main pipe is omitted because the flow direction arrow (7) of the cooling water in FIG. 3 is simply reversed.

Next, the effect will be explained.

In large-capacity turbine generators that have become smaller and smaller in recent years, by moving the multi-branch main pipe (2) and the multi-branch merging main pipe from the complex and narrow interior of the C1 machine to the outside of the machine, the insulated connecting pipe (3) By ensuring sufficient length and allowing plenty of space inside the machine, it allows for good cooling of each component that is normally generated in an electric machine, and the larger working space makes brazing work easier, making it the most disliked brazing machine as an electric machine. Leakage of cooling water due to poor brazing from the attached connection part (8) can be prevented in advance.

In addition, it is an inner cage type, and when the stator frame (5) is removed and transported, the flexibility of the insulated connecting tube (3) is used to direct it toward the center, which is different from the conventional inner cage (5). ) Since there is no multi-branch main pipe (2) and multi-branch merging main pipe, which are dimensionally critical due to transportation restrictions on the side, the external packaging dimensions can be significantly reduced.

It should be noted that the present invention is not limited to the embodiments described above and shown in the drawings, but can be applied to other liquid-cooled rotating electric machines, for example, and can be implemented with various modifications without changing the gist thereof. Of course it can be done.

[Effects of the Invention] As explained above, according to the present invention, the multi-branching and merging main tubes that supply and discharge cooling liquid to and from each winding are not complicated and narrow in the internal structure of a rotating electric machine, high-potential current-carrying parts, etc. By installing it outside the stator frame outer peripheral plate from the space, a sufficient length of the insulated connecting tube can be ensured, and the workability and reliability of the brazed connection between the main tube and the insulated connecting tube can be improved. It is possible to provide a highly reliable liquid-cooled rotating electrical machine that can be greatly improved.

[Brief explanation of drawings]

1 and 2 are longitudinal cross-sectional views showing main parts of different conventional liquid-cooled rotating electric machines, respectively. FIG. 3 is a cross-sectional perspective view showing main parts of an embodiment of the liquid-cooled rotating electric machine of the present invention, and FIG. FIG. 4 is a perspective view showing the insulated connecting tube of FIG. 3 bent toward the center. 1... - winding wire 2... multi-branch main pipe 3...
Insulated connection pipe 4... Stator core 5... Inner cage 6... Stator frame 8... Brazed connection part
9... Outer plate agent Patent attorney Mr. Inoue Figure 1 Figure 3

Claims (2)

[Claims] (1) In a liquid-cooled rotating electrical machine equipped with a stator winding in which the winding conductor is hollow and a cooling liquid flows through the hollow part,
A liquid-cooled rotating electric machine, characterized in that a multi-branch and merging main pipe for supplying and discharging cooling liquid to and from the stator windings are arranged on the outside of a circumferential plate of a stator frame around a quadruple roll machine. (2) The stator core, on which the stator windings are wound, is attached to the inner cage, and the insulating connection tubes connecting the stator windings to the branching and merging bus tubes are placed on the center side of the rotating electric machine. A liquid-cooled rotating electrical machine according to claim 1, characterized in that the machine is bendable.