JPS6051344B2 - Ventilation cooling system for vertical turbine generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a one-side ventilation cooling device for a vertical water turbine power generating column.

First, a conventional ventilation cooling device of this type will be explained with reference to FIG.

In FIG. 1, reference numeral 1 denotes a shaft that is vertically arranged and rotatably supported by a bearing (not shown).

2 is a spider boss, 3 is a spider flange, and 4 is a plurality of spider arms arranged at intervals in the circumferential direction and extending in the axial and radial directions, and these constitute a spider.

5 is kotsuta, 6 is kotsuta 5 at the tip of spider arm 4
7 is a ventilation duct provided on the yoke 6; 8 is a ball core fixed to the yoke 6; 9 is a
is a field coil that excites this core 8, and these parts constitute the rotor side.

Further, 10 is an armature coil, 11 is a stator core, 12 is a ventilation duct provided in the stator core 11, and 13 is a stator support plate 14a located at both upper and lower ends of the stator core 11 in the stator frame 14. The provided ventilation holes 14 are the stator frame, and 15 is an air cooler that cools the air that has been heated through the inside of the machine, and is attached to the stator frame 14.

16 is an upper ventilation guide having a circular suction hole 16a in the center, 17 is an upper dividing plate, 18 is a lower partition plate, 19 is a foundation made of concrete, etc., and these constitute the stator side. .

The flow of cooling air during operation of the vertical shaft water turbine generator configured in this manner is as shown by the arrows in the figure.

That is, the cooling air coming out of the air cooler 15 is pushed upward, passes around the outer periphery of the upper ventilation guide 16, and is subjected to a fan action by the rotation of the plurality of spider arms 4 extending in the axial and radial directions, that is, the cooling air is moved inside. Due to the effect of circulating from the circumferential side to the outer circumferential side, it is popular from the ventilation window 23 between the spider flange 3 and the yoke 6, and the gap between the upper ventilation guide 16 and the spider arm 4,
Part of it is the upper ventilation guide 16 and the yoke 6, as shown by arrow A.
The other part flows into the gap between the spider arms 4 and 4, and the other part flows in the radial direction as shown by the arrow C, and the other part flows into the yoke 6 as shown by the arrow 2. and the foundation 19 (forming the lower ventilation guide), and the other flows to the stator side. By the way, since the gap between the upper ventilation guide 16 and the yoke 6 and the gap between the yoke 6 and the foundation 19 are generally configured to be approximately equal, until now the cooling air flowing through these gaps has been Naturally, the flow rate is also balanced, and it is thought that good ventilation cooling is being performed. However, the cooling air flowing in the radial direction has a small flow rate through the ventilation duct 7 of the yoke 6, and most of it collides with the yoke 6 and flows in the opposite direction as shown by the arrow H. By E, the cooling air A flowing through the gap between the upper ventilation guide 16 and the yoke 6 is blocked, reducing the air volume and increasing wind loss.

In addition, due to the influence of the cooling air in the opposite direction and the fan action caused by the rotation of the plurality of spider arms 4 extending in the axial and radial directions, that is, the action of circulating the cooling air from the inner circumferential side to the outer circumferential side, Most of the cooling air flows downward, and the amount of cooling air A flowing through the upper gap is much smaller than the amount of cooling air II flowing through the lower gap, so the upper coil of the armature coil 10 As a result of a water flow model experiment, it was found that the end part was not cooled sufficiently.
SUMMARY OF THE INVENTION An object of the present invention is to provide a ventilation cooling device for a rotating electrical machine that eliminates the drawbacks of the prior art described above and has excellent cooling efficiency.

To achieve this objective, the present invention provides a lower ventilation guide that covers the lower inner peripheral part of the spider arm and blocks the cooling air flowing through this part, and an upper ventilation guide for the outer diameter of the lower ventilation guide. The ratio of the diameter of the center side suction hole is 0
．． It is characterized in that it is set to 8 to 1.0.

An embodiment of the present invention will be described below with reference to FIG.

In FIG. 2, the same reference numerals as in FIG. 1 indicate the same or equivalent components. The difference from the conventional example shown in FIG. 1 is that a disk-shaped lower ventilation guide 20 is attached to the lower inner peripheral portion of the spider arm 4 so as to cover this portion. A partition plate 18 is provided at a position facing the outer circumferential portion of the frame, and the other structure is the same as that of the conventional example shown in FIG. Here, the inner diameter of the upper ventilation guide 16,
That is, the ratio DUf/D. of the diameter DOf of the circular suction hole 16a and the outer diameter Ddf of the lower ventilation guide 20. f is set to 0.8 to 1.0 for the following reasons.

When air is sent to a pipe or device (in this case, a cooler), there is resistance inherent in that pipe or device, so the pressure needed to overcome this resistance is applied to the fan action of the blower (in this case, a spider). Therefore, the air must be produced by a water turbine generator (which sends out the air), but the above-mentioned inherent resistance is generally proportional to the square of the air volume, as shown by curve R in Figure 3.

A curve R showing resistance to this air volume (or wind speed) is called a resistance curve. In addition, when the wind pressure at the cooler mounting position on the stator frame is H1 and the total air volume passing there is Q, the Q (air volume) - H (wind pressure) characteristic of the generator is given by the curve H in Figure 3. . On the other hand, curve R shows the pressure loss that occurs when the air flow rate through the cooler is Q. Therefore, the amount of air that can be blown into the cooler is determined by the point where the resistance of the cooler and the wind pressure of the generator are equal, that is, the intersection Qp of curve R and curve H in Figure 3.
(Rp=Hp), and this point is particularly called the operating point, and the windage loss at this operating point air volume Qp is called the operating point windage Wp. Operating point windage Wp with respect to operating point air volume Qp
The ratio Wp/Qp indicates how much operating point windage loss Wp is required to send the operating point air volume Qp, and is a criterion for determining ventilation efficiency.

Naturally, it is desirable for the blower to have a smaller operating point windage loss Wp, so it can be said that the smaller the ratio Wp/Qp is, the better it is. By the way, in the case where the lower ventilation guide 20 is provided as shown in FIG. 2, the ratio of the inner diameter Duf of the soil side ventilation guide 16 to the outer diameter Dd of the lower ventilation guide 20 is
By changing D, , the distribution of flows A and 2 in Figure 2 can be adjusted. When the distribution is poor, the circulation of the cooling air is poor, resulting in a decrease in air volume, and in the areas where the air does not flow (stagnation points), local vortices like flow holes are generated, increasing ventilation loss. As a result, the value of Wp/Qp increases and ventilation efficiency decreases. Note that the radius of the spider arm, the distance between the spider arm, the upper ventilation guide, and the foundation, and the distance between the yoke, the upper ventilation guide, and the foundation are also related to the flow of cooling air, but their influence on Wp/Qp is relatively small, and DOr /Dd, is dominant. So, D. , /Daf(5W, /Q9) was measured by a water flow model experiment (a test in which a scale model of a generator is rotated in water to evaluate ventilation performance), and the results shown in Figure 4 were obtained. From this figure 4, D.f/D
When d is in the range of 0.8 to 1.0, Wp/Qp is small;
It can be seen that when this range is exceeded, Wp/Qp increases rapidly and ventilation efficiency becomes extremely poor.

Therefore, as in the above embodiment, the upper ventilation guide 16
The ratio D of the inner diameter Duf of the lower ventilation guide 20 and the outer diameter Ddf of the lower ventilation guide 20
By setting uf/Ddf to 0.8 to 1.0,
By reducing Wp/Qp, ventilation efficiency, that is, cooling efficiency, can be increased.

That is, the lower ventilation guide 20 is provided, and its outer diameter D
Ratio D1 of the inner diameter D of the upper ventilation guide 16 to df;
By setting . Since they are made almost equal, it is thought that the ventilation amounts of cooling air A flowing through the upper gap and cooling air II flowing through the lower gap are almost balanced, resulting in a good ventilation cooling effect.

Also, at this time, the cooling air in the opposite direction is also suppressed,
This is considered to be the minimum value. Further, FIG. 5 shows another embodiment of the present invention. In this embodiment, a lower ventilation guide 21 that covers the inner peripheral portion of the spider arm 4 is provided on the base side close to the spider arm 4, and is formed in a shape that also serves as a lower partition plate. Supported. The rest of the structure is similar to the embodiment shown in FIG. Therefore, not only can the same effects as in the embodiment described above be obtained, but the work of attaching the lower ventilation guide to the spider arm is no longer necessary, and costs can be reduced accordingly.

Furthermore, FIG. 6 is a modification of FIG. 5, in which the lower ventilation guide 2
The outer circumferential portion of No. 1, that is, the portion corresponding to the partition plate, is inclined along the flow of cooling air.

Therefore, ventilation resistance can be reduced and ventilation efficiency can be further improved. In each of the above embodiments, the inner circumference of the upper ventilation guide 16° and the lower ventilation guide 20 or 21
Although the shape of the outer periphery has been described as circular, these shapes can also be polygonal, uneven, etc. in addition to circular.
In this case, the average diameter is the inner diameter DO or the outer diameter Ddf
Considering this, it is sufficient to set Duf/Ddf to 0.8 to 1.0.

As explained above, according to the present invention, a lower ventilation guide is provided that covers the lower inner circumferential portion of the spider arm and blocks the cooling air flowing through this portion, and an upper ventilation Since the ratio of the diameters of the center side suction holes of the guide is set to 0.8 to 1.0, ventilation efficiency can be improved and good ventilation cooling can be performed.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing a conventional ventilation cooling device for a vertical shaft water turbine generator, FIG. 2 is a longitudinal sectional view showing a ventilation cooling device for a vertical shaft turbine generator according to an embodiment of the present invention, and FIG. The figure is a characteristic diagram showing the relationship between resistance, wind pressure, and windage loss with respect to the air volume of the blower. Figure 4 is a characteristic diagram showing the ventilation efficiency of a one-side ventilation type rotating electrical machine. Figures 5 and 6 are each other according to the present invention. 1 is a vertical cross-sectional view showing a ventilation cooling device for a vertical water turbine generator according to an embodiment.

Claims (1)

[Claims] 1. A shaft disposed vertically and rotatably supported, a yoke attached to this shaft via a spider, a rotor consisting of a plurality of poles supported by this yoke, and this rotor. A stator core disposed opposite to the rotor with a gap in between, a stator coil wound around the stator core, and a fixing that covers the outer circumference of the stator core and supports the stator core. A stator consisting of a child frame,
The air heated through the upper ventilation guide and foundation, which are arranged on both the upper and lower sides of the rotor and stator and have a central suction hole connected to both the upper and lower ends of the stator frame, and the stator. the spider includes a spider boss fixed to the shaft, and an axial and radial air cooler attached to the spider boss via a spider flange and spaced apart from each other in the circumferential direction. It consists of a plurality of spider arms extending in the direction, and the cooling air cooled by the air cooler is sucked between the spider arms through the center side suction hole of the upper ventilation guide, and the cooling air is drawn between the upper side of the yoke and the upper ventilation guide. Ventilation of a vertical shaft water turbine generator is made to flow between each of the poles through a gap between the poles and a gap between the lower surface of the yoke and the foundation, and from there to the stator side. In the cooling device,
A lower ventilation guide is provided to cover the lower inner peripheral portion of the spider arm, and the ratio of the diameter of the central suction hole of the upper ventilation guide to the outer diameter of the lower ventilation guide is set to 0.8 to 1.0.
A ventilation cooling device for a vertical shaft water turbine generator, characterized in that it is set as follows. 2. The ventilation cooling device for a vertical shaft water turbine generator according to claim 1, wherein the lower ventilation guide is provided on the spider side. 3. The ventilation cooling device for a vertical shaft water turbine generator according to claim 1, wherein the lower ventilation guide is provided on the foundation side close to the spider.