JPH0218681Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a rotor for a rotating electrical machine that reduces ventilation power loss and improves efficiency.

[Prior Art] Hereinafter, a salient pole rotor of a rotating electrical machine such as a synchronous machine will be described as an example.

A salient pole rotor of a conventional synchronous machine is shown in FIGS. 1 and 2 as a vertical sectional view and a partial plan sectional view. The figure shows the case of a vertical shaft type, where 1 is a rotating shaft, 2 is a rotor spider, and 3 is a rim that is firmly fixed to the rotor spider and forms a yoke for the rotor. Reference numeral 4 denotes a plurality of radial ventilation ducts provided on this rim, and ventilation intervals are formed by a plurality of duct pieces 5 and a spacing ring 6. 7 is a tightening bolt for the rim 3, and 8 is a nut. Reference numeral 10 denotes a plurality of salient pole-shaped magnetic pole cores made of laminated thin steel plates, which are fastened with tightening bolts and fixed to the outer periphery of the rim 3. 11 is the magnetic pole core 10
The field coil fitted in, 9 is the magnetic pole and the magnetic pole iron core 1
0 and a field coil 11. 12 is a fan attached to the rim 3.

Next, 13 is a stator frame, 14 is a stator core fixedly supported by this stator frame, and a radial ventilation duct 15 is provided. 16 is a stator coil, and 17 is an end enclosure. 18 is a rotor from 1 to
12, and 19 is a stator, which is made up of 13 to 17. 20 is an air gap formed between the rotor 18 and the stator 19.

In the conventional device described above, when the rotor 18 rotates, the cooling gas such as cooling air flowing in by the fan 12 cools the end of the field coil 11 and the end of the stator coil 16 as shown by the arrow. Cool this through. In addition, the cooling air that has entered the inner diameter side of the rotor spider 2 passes through the ventilation duct 4,
It flows between adjacent field coils 11 as shown by the arrows to cool them. The cooling air passing between the field coils 11 is affected by the fan action of the salient poles, blows out into the air gap 20, and then passes through the stator ventilation duct 15.
The stator coil 16 and the stator core 14 are cooled through the air.

However, the mechanical loss (slip loss) of the rotor 18 is divided into wind loss and bearing loss, and wind loss is consumed as the power necessary for ventilation, and the ventilation power loss increases as the air volume increases, and the surrounding gas The loss consumed by friction with the airflow is divided into friction loss, which is constant and unrelated to the air volume.

[The problem that the idea attempts to solve]

Since the rotor of a conventional rotating electric machine is configured as described above, the cooling gas flowing between the magnetic poles 9 and into the air gap has the same peripheral speed (same angular velocity) as the magnetic poles 9 due to the fan action of the magnetic poles 9. given,
It is ejected into the air gap 20 with this circumferential velocity (angular velocity), and is ejected into the air gap 20 with a large angular momentum.

However, after passing through the air gap 20, the stator 1
9, the cooling gas is converted into a flow only in the radial direction by the ventilation duct 15 provided in the radial direction, so that the angular velocity of the cooling gas in the air gap 20 becomes zero. becomes. Therefore, a large angular momentum in the air gap 20 is wasted in changing the flow, resulting in a loss of ventilation power, resulting in a problem in that sufficient efficiency cannot be obtained.

This idea was made in order to eliminate the problems of the conventional ones as described above, and it is fixed to the end of one of the adjacent magnetic poles in the opposite direction to the rotational direction of the magnetic pole head, and the magnetic pole head of the other magnetic pole is A guide cover is provided which forms a jetting path between the magnetic poles and the air gap, and the outlet of the cooling gas spouted from between the magnetic poles to the air gap is throttled so that the cooling gas is spouted from the jetting path in a direction opposite to the rotational direction of the rotor. It is an object of the present invention to provide a rotor for a rotating electrical machine that can reduce the ventilation power loss of cooling gas ejected into an air gap and obtain sufficient efficiency.

[Means for Solving the Problems] A rotor of a rotating electrical machine according to this invention is fixed to an end of one of the adjacent magnetic poles on the side opposite to the rotational direction of the magnetic pole head without protruding toward the air gap side, It is equipped with a guide cover that forms an ejection path between it and the other magnetic pole head.

[Effect]

The guide cover for the rotor of a rotating electric machine according to this invention narrows the outlet of cooling gas such as cooling air to the air gap side, and passes the cooling gas from the rotor spider side through the ventilation duct of the rotor rim and between the magnetic poles. The air is ejected from the ejection passage into the air gap in the opposite direction to the rotational direction of the rotor.

[Example of idea]

Hereinafter, the configuration of a rotor of a rotating electric machine according to an embodiment of this invention will be explained based on the drawings. In FIGS. 3 to 6, numerals 1 to 20 are the same as the conventional device described above. Reference numeral 21 denotes a guide cover that is fixed to the end of the adjacent magnetic pole 9 in the opposite direction to the rotating direction of the magnetic pole head with a bolt (not shown) or the like, and forms an ejection path 22 between it and the other magnetic pole 9 head. An air gap 2 is provided over almost the entire length of the magnetic poles 9 in the axial direction, constitutes the outer peripheral surface of the rotor 18 together with the outer peripheral surface of the magnetic pole iron core 10, and is used for cooling gas passing between the magnetic poles 9.
The outlet toward the 0 side is throttled so that when the cooling gas is ejected from the ejection path 22 to the air gap 20, it is ejected in a direction opposite to the rotational direction of the rotor 18. A seal plate 23 is provided between the magnetic poles 9 to prevent the cooling gas flowing between the magnetic poles 9 from the ventilation duct 4 provided on the rim 3 from flowing out from above and below the magnetic poles 9.

The guide cover 21 is preferably made of a non-magnetic material that is free from overheating due to eddy currents since it is used in a high magnetic field.
SUS304, SUS316 or aluminum, FRP specified by G4304 (hot rolled stainless steel plate)
(glass fiber reinforced plastic), thermosetting resin laminate, etc.

In the above configuration, due to the rotation of the rotor 18,
As in the conventional case, the cooling gas that has entered the inner diameter side of the rotor spider 2 passes through the ventilation duct 4 and flows between adjacent field coils 11 to cool them. The outlet of the cooling gas passing between the magnetic poles 9 to the air gap 20 side is narrowed by the guide cover 21, the wind speed is increased, and the fan action of the salient poles is added, resulting in a blowout path 22 between the head of the magnetic pole core 10 and the guide cover 21. The air is ejected from the air gap 20 in the direction opposite to the direction of rotation of the rotor 18. The cooling gas that has passed through the air gap 20 passes through the ventilation duct 15 of the stator 19 and cools the stator coil 16 and the stator core 14. Further, the circulation of cooling gas by the fan 12 is the same as in the conventional device described above. The principle by which ventilation power loss is reduced by doing this will be explained using the speed triangle in FIG. 5, which shows the relationship between the circumferential speed of the rotor 18 and the speed of the cooling gas.

As can be seen from this velocity triangle, the absolute velocity v of the cooling gas at the exit portion of the magnetic pole 9 is determined by the combination of the circumferential velocity u of the magnetic pole 9 and the relative velocity w of the cooling gas with respect to the magnetic pole. Here, v corresponds to v ₁ and v ₂ and w corresponds to w ₁ and w ₂ . In the conventional device, the cooling gas passing between the magnetic poles 9 is given almost the same peripheral speed as the magnetic poles 9 due to the fan action of the magnetic poles 9, so the relative velocity w ₁ of the cooling gas with respect to the magnetic poles 9 is almost outward, and the relative speed
The angle β ₁ that w ₁ forms with the outward direction of the center line between the magnetic poles approaches 0°. As a result, the circumferential velocity component of the absolute velocity v ₁ of the cooling gas
u ₁ becomes close to the circumferential speed u of the rotor 18. In contrast, in this invention, a guide cover 21 is attached to the magnetic pole head, and the guide cover 21 directs the jetting direction of the cooling gas in a direction opposite to the rotation direction. Therefore, the relative velocity of the cooling gas to the magnetic pole 9 is
w ₂ is largely inclined (angle β ₂ ) in the direction opposite to the circumferential speed with respect to the outward direction of the center line between the magnetic poles. As a result, the circumferential velocity component u ₂ of the absolute velocity v ₂ of the cooling gas can be made considerably smaller than the circumferential velocity u of the rotor 18, and when the amount of ventilation is the same, the ventilation power is the circumference of the absolute velocity of the cooling gas jetted into the air gap 20. Because it is proportional to the velocity component
u ₂ /u becomes ₁ times smaller. That is, as the circumferential velocity component of the absolute velocity of the cooling air jetted into the air gap 20 becomes smaller, the angular momentum becomes smaller, and the ventilation power loss becomes smaller.

In this way, the cooling gas ejected from between the adjacent magnetic poles 9 into the air gap 20 is ejected in the opposite direction to the rotational direction by the guide cover 21, so that the circumferential velocity (angular velocity) of the cooling gas at the ejection part is Since the circumferential speed of the child 18 is considerably lower than that of the child 18, the angular momentum of the cooling gas in this portion is also small. Therefore, by eliminating this in the air gap 20, the resulting ventilation power loss is reduced.

[Effect of idea]

As explained above, this idea includes a guide cover that is fixed to the head of one of the adjacent magnetic poles and forms a blowout path between the head of the other magnetic pole, and the cooling gas that blows out from between the magnetic poles into the air gap. Since the outlet to the air gap side is throttled and the cooling gas is ejected from the ejection path to the air gap in the opposite direction to the rotational direction of the rotor, the ventilation power loss can be reduced and sufficient efficiency can be obtained.

[Brief explanation of the drawing]

Figure 1 is a longitudinal cross-sectional view showing a conventional salient pole rotor.
Figure 2 is a sectional view taken along the - line in Figure 1;
The figure is a longitudinal sectional view showing a salient pole rotor according to an embodiment of this invention, FIG. 4 is a sectional view taken along the - line in FIG. 3, and FIG. 5 is a principle diagram for explaining the principle of this invention. FIG. 6 is a partially enlarged view of FIG. 4. In the figure, 2 is a rotor spider, 18 is a rotor, 20 is an air gap, 21 is a guide cover,
22 is a jetting passage. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a rotor of a rotating electrical machine in which cooling gas is jetted from the rotor spider side to the air gap side through a ventilation duct formed in the radial direction, one of the adjacent magnetic poles. It is fixed to the end of the head in the direction opposite to the direction of rotation without protruding toward the air gap side, and forms an ejection path between it and the other magnetic pole head, and also provides an outlet for the cooling gas to the air gap side. The throttle includes a guide cover that causes the cooling gas to be ejected from the rotor spider side, through the ventilation duct of the rotor rim, between the magnetic poles, and from the ejection path to the air gap in a direction opposite to the rotational direction of the rotor. The rotor of a rotating electric machine. (2) The rotor of a rotating electric machine according to claim 1, wherein the material of the guide cover is a non-magnetic material. (3) The rotor of a rotating electrical machine according to claim 2 of the utility model registration claim, wherein the material of the guide cover is stainless steel.