JPS6126449A - Stator of rotary electric machine - Google Patents

Abstract

PURPOSE:To accurately distribute cooling air amount flowed through the end of a stator winding and each exhaust chamber at the prescribed rate by providing an independent vent passage for directly coupling the exhaust chamber provided in a stator frame with the final exhaust chamber. CONSTITUTION:A stator frame 1a is provided inside a cylindrical frame 1, and the frame 1a is mainly formed of a plurality of hollow disk-shaped partition plates (A)-(D). Exhaust chambers (a)-(d) are formed of the plates (A)-(D), and the final exhaust chamber (e) for collecting cooling airs of the chambers (a)-(d) is provided at the end of the frame 1a. The chamber (e) and the chambers (a)- (d) are directly coupled by a vent passage, i.e., a communicating tube 8. In this case, the passage is independently provided so as not to mix with cooling air flowed to the other, i.e., cooling air in the exhaust tube through which the tube 8 is, for example, passed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an improvement in a stator for a rotating electrical machine, and particularly to an improvement in a stator for a pulp generator.

[Background of the invention]

In general, a pulp generator is mainly composed of a stator placed inside a cylindrical frame, a rotor that rotates within this stator, and a water wheel that drives this rotor, and is buried in a water stream. It is normal that this is done.

Therefore, in this type of generator, the stator and rotor are cooled by cooling air circulating within the cylindrical frame.

FIG. 6 shows a cross section of the main parts of the pulp generator. What is shown as 1 in the figure is a cylindrical frame, and a stator core 2 and a stator winding 3 are arranged inside this cylindrical frame via a stator frame 1a.

Further, inside thereof, a rotor core 5 and a rotor winding 6 which rotate together with the rotor shaft 4 are provided.

Next, to explain the flow of cooling air by describing its circulation system path and surrounding structure, the cooling air is sent out radially from the rotor core 5, passes through the cooling grooves of the stator core 2, or is fixed to the They pass through the three end portions of the stator windings outside the child core and are discharged into the exhaust chambers abcd of the stator frame 1a, respectively. Each of the partition plates forming the stator frame has communication holes ABCD for ventilation, and the cooling air passing through these holes is discharged to the final exhaust chamber e. This discharged air passes through an air cooler 7 previously installed in the machine, enters the rotor again, and is circulated. In this case, for example, air in the exhaust chamber a enters the exhaust chamber through the communication hole A, where it joins with the exhaust from the stator core 2, passes through the communication hole B, and eventually enters the final exhaust chamber e. In this way, the exhaust from the stator and the air passing through the communication holes are combined and discharged to the next exhaust chamber through another communication hole. Therefore,
In general, the exhaust communication holes are gradually increased in diameter as shown in Figure 7, or by increasing the number of holes to increase the amount of cooling air at the ends of the stator windings. The structure is such that the amount of displacement from the iron core is a predetermined ratio.

However, in this structure, the size or number of holes is determined by calculation and cannot be adjusted later, so cooling ventilation is not necessarily carried out at a predetermined rate.
The reality is that there is no way to confirm that percentage.

In particular, as the capacity of the generator increases, the number of exhaust chambers must also increase from the standpoint of mechanical strength, and the amount of cooling air must also increase, making it impossible to obtain cooling air at a specified rate, resulting in partial However, there were drawbacks such as insufficient cooling of the windings and iron core, resulting in overheating.

[Purpose of the invention]

The present invention was conceived with this in mind, and its purpose is to be able to accurately distribute the amount of cooling air flowing through the ends of the stator windings and each exhaust chamber into predetermined proportions. Our company provides stators for rotating electric machines.

[Summary of the invention]

That is, the present invention achieves the intended purpose by providing a ventilation path between the exhaust chamber and the final exhaust chamber, each directly connecting the exhaust chamber and the final exhaust chamber. This is what I did.

[Embodiments of the invention]

The present invention will be explained below based on the illustrated embodiments. 1st
4 to 4 show the cylindrical frame and stator frame portions, and a stator frame 1a is provided inside the cylindrical frame body 1. As shown in FIG. This stator frame is mainly composed of a plurality of hollow disk-shaped partition plates A11B and H2, and these partition plates separate exhaust chambers A, B, and C.

d is formed. Furthermore, a final exhaust chamber e is provided at the end of the stator frame 1a to collect cooling air from each exhaust chamber.

This final exhaust chamber e and each exhaust chamber a, b, c.

d and are directly connected to each other by ventilation passages, that is, communication pipes 8, 9, and 10. What is important in this case is that this ventilation channel is provided independently so that it does not mix with the cooling air flowing elsewhere, for example in the exhaust chamber through which the communication pipe passes. In the diagram, 3 indicates the stator winding, 5 indicates the stator core, and 5a indicates the cooling groove provided in the stator core (only one is shown in the figure, but in reality, multiple cooling grooves are provided in the longitudinal direction). ) is also d.

By arranging the communication pipes in this way, for example, the cooling air from the end coil will not merge with the exhaust air from the iron core midway.
Since the gas is directly discharged to the final exhaust chamber e and is discharged through a pipe with a constant cross section, pressure loss due to sudden changes in cross section is also reduced. Furthermore, since the flow of cooling air can be treated as a rectified flow rather than a turbulent flow, it can be calculated with high accuracy. Note that FIG. 4 shows a communicating hole from the exhaust chamber d adjacent to the final exhaust chamber e, and in this case, no pipe is required. A predetermined number of the exhaust communication pipes described above are arranged evenly on the circumference. According to this configuration described above, the prescribed distribution of cooling air can be easily achieved, but furthermore, because the final exhaust chamber is structurally accessible to workers, it is possible to easily distribute the cooling air as shown in Fig. 5. It is also possible to attach an adjustment plate 11. Since the adjustment plate 11 allows fine adjustment of the cooling air volume, it is possible to further achieve the desired air volume distribution.

Further, the strength of the stator frame can be increased by arranging the above-mentioned communicating pipes and communicating holes so that the heights Hl l H2 of the communicating pipes shown in FIG. 1 are approximately equal. In other words, bending stress is generated during operation in the disc-shaped partition plate of the stator frame in which the hole through which this communication pipe is passed is provided, but by setting Hl ==) (2), this hole is placed at the neutral point. This prevents the bending strength from decreasing.

〔Effect of the invention〕

As explained above, the present invention provides an independent ventilation path that directly connects the exhaust chamber provided in the stator frame to the final exhaust chamber, so that cooling air is transferred from the exhaust chamber to the final exhaust chamber. It does not merge with other cooling air on the way to the chamber, which means there is no turbulence or flow obstruction in the ML flow of the cooling air, and therefore the ends of the stator windings and each exhaust chamber are The amount of circulating cooling air can be accurately distributed at a predetermined ratio.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional side view showing the main parts of the stator of the rotating electric machine of the present invention, FIGS. 2 to 4 are longitudinal sectional side views of the same part as in FIG. FIG. 6 is a vertical side view showing a part of the ventilation passage of another embodiment of the stator of the rotating electrical machine of the present invention; FIG. FIG. 7 is an enlarged vertical sectional side view of the stator frame shown in FIG. 6. DESCRIPTION OF SYMBOLS 1... Cylindrical frame body, 1a... Stator frame, 3... Stator winding, 5... Stator core, 5a... Cooling groove, a,
b, c, d...exhaust chamber, e...final exhaust chamber, 8,9
．． 10...Continuous Taku 1 Diagram! 2nd item 3rd figure l+ figure 5th figure

Claims (1)

[Claims] 1. A stator core having cooling grooves having predetermined intervals in the axial direction and penetrating in the radial direction, a stator winding wound around the stator core, and the stator a stator frame provided on the outer periphery of the iron core, and the stator frame has a plurality of exhaust chambers that collect cooling air released from the cooling grooves of the stator core, and a plurality of exhaust chambers for each of these exhaust chambers. In a stator of a rotating electrical machine having a final exhaust chamber that further collects the collected cooling air, the exhaust chambers and the final exhaust chamber are directly connected between the plurality of exhaust chambers and the final exhaust chamber, respectively. A stator for a rotating electric machine characterized by having an independent ventilation passage. 2. The stator of a rotating electric machine according to claim 1, wherein the ventilation passage is provided with an air volume adjustment means that can adjust the amount of cooling air flowing through the ventilation passage.