JP2000245108A - Cooling construction of rotating electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform effective cooling by eliminating the difference between the right-side and left-side temperatures of a rotating electric machine. SOLUTION: In the cooling construction for a rotating electric machine, an air-cooled heat exchanger 102 mounted on the upper surface of a motor 101 is partitioned into three chambers 124a-124c by baffle plates 123a, 123b. When an inside air circulating blower 131 provided on the axial center upper surface of the heat exchanger 102 is operated, inside air (shown by the arrow of a full line) in the center space of the motor 101 is sucked into the blower 131 via the center chamber 124b, pushed in by the blower 131, and divided and caused to flow separately into the chambers 124a, 124c on both sides, and are supplied to both end spaces of the motor 101. Furthermore, they flow into axial ventilating holes 112a, 114a and cooling ventilating ducts 112b, 114b. Consequently, inside air cooled to approximately the same temperature are fed to both end sections of the motor 101, and the temperatures of both end sections of the motor 101 become approximately equal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling structure for a rotating electric machine, which is devised so as to eliminate a temperature difference between both ends of the rotating electric machine and to provide effective cooling. In particular, the present invention mounts an air-cooled heat exchanger on the upper surface of the rotating electric machine in order to cool the rotating electric machine (for example, a three-phase induction motor, a generator, etc.) by a fully closed and forced ventilation structure. The cooling efficiency is improved by devising the type of cooling structure.

[0002]

2. Description of the Related Art In order to air-cool a rotating electric machine by a fully-closed other-force ventilation structure system, a system in which cooling air flows in one direction is currently employed in order to simplify the flow of cooling air.
This specific example will be described with reference to FIG.

[0003] As shown in FIG.
The air-cooling heat exchanger 2 is mounted (mounted). The air-cooling heat exchanger 2 is connected to a blower 31 for circulating inside air and a blower 32 for ventilating outside air.

The electric motor 1 has a stator 12 installed on an inner peripheral surface of a frame 11, and a rotor 13 mounted on a shaft 13.
The shaft 13 is rotatably supported by a bracket 16 via a bearing 15. An axial ventilation hole 12a is formed in the stator 12, and the rotor 14
Is formed with an axial ventilation hole 14a. Frame 1
Opening portions 11a and 11b at both left and right ends of the upper surface
Are opened, and the internal space of the electric motor 1 and the internal space of the air-cooled heat exchanger 2 communicate with each other through the openings 11a and 11b.

[0005] In the air-cooled heat exchanger 2, a large number of pipes 22 having an elliptical cross-sectional shape penetrate through one end surface 21a and the other end surface 21b of the heat exchanger frame 21 having a box shape. It is attached. In the heat exchanger frame 21, three baffles (baffles) 23a,
23b and 23c are arranged, and the heat exchanger frame 2
One interior space has four rooms 24a, 24b, 24c, 24
d. Further, openings 25a and 25b are opened in portions of the upper surface of the heat exchanger frame 21 corresponding to the rooms 24a and 24b.

The outside air ventilation blower 32 draws in outside air (indicated by a dotted arrow in the figure), and supplies the outside air to the left end face of each pipe 22 via a ventilation cover 33. For this reason, outside air circulates through the internal space of each pipe 22,
Air is exhausted from the right end face of each pipe 22. In this way, by circulating the outside air through the pipe interior space, the air (inside air) in the interior space of the heat exchanger frame 21 can be air-cooled.

The blower 31 for circulating inside air is provided with an air duct 34.
Is in communication with And the air duct 34 has the opening 2
The interior air circulation blower 31 communicates with the room 24b through the opening 25b. Therefore, when the inside air circulation blower 31 is driven,
Inside air (indicated by a solid arrow in the drawing) in the room 24a is sucked into the inside air circulation blower 31 through the air duct 34, and the sucked inside air is pushed out from the inside air circulation blower 31. Room 24b, Room 24
c and the room 24d are sequentially circulated and sent to the left internal space of the electric motor 1.

The inside air in the left internal space of the electric motor 1 flows to the right side in the axial direction through the axial ventilation holes 12a, 14a and the like.
It reaches the inner space on the right side of the electric motor 1 and flows into the room 24a again. Thus, the inside air circulates and circulates between the internal space of the electric motor 1 and the internal space of the air-cooled heat exchanger 2. And while the inside air heated in the internal space of the electric motor 1 flows in each room 24a-24d of the air-cooled heat exchanger 2 zigzag,
It is cooled by touching the pipe 2.

[0009]

In the prior art shown in FIG. 2, the inside air flows in one direction, that is,
a → blower for internal air circulation 31 → rooms 24b, 24c, 24
It flows along a one-way circulation path of d → left internal space of the electric motor 1 → right internal space of the electric motor 1 → room 24a. Therefore, the temperature of the inside air in the left internal space of the electric motor 1 is low, but the temperature of the inside air in the right internal space of the electric motor 1 is high. Therefore, the temperature of the right portion (for example, the right coil temperature C2) of the electric motor 1 becomes higher than the temperature of the left portion (for example, the left coil temperature C1) of the electric motor 1. That is, a temperature difference (temperature gradient) occurs between the left and right sides in the axial direction of the electric motor 1. For this reason, uniform cooling was not possible, the cooling efficiency was low, and the maximum temperature tended to increase.

[0010] In the prior art shown in FIG.
Since the rooms 24a to 24d of the air-cooling heat exchanger 2 are zigzagly circulated, the ventilation path is long and the ventilation resistance is large, and a large-sized blower is required as the inside-air circulation blower 31.

A technique designed to reduce the thermal gradient by providing a blower for circulating air inside the upper part of the air-cooled heat exchanger mounted on the upper surface of the rotating electric machine (see Japanese Utility Model Application Laid-Open No. 53-863).
No. 06), but it was still insufficient in reducing the thermal gradient and making the cooling more efficient.

SUMMARY OF THE INVENTION In view of the above prior art, an object of the present invention is to provide a cooling structure for a rotating electric machine that can effectively cool and reduce the capacity of a blower.

[0013]

According to the structure of the present invention, which solves the above-mentioned problems, an air-cooled heat exchanger formed by penetrating a heat exchanger frame through a number of pipes through which outside air flows in the pipe inner space is rotated. A cooling structure for a rotating electric machine, mounted on an upper surface of an electric machine, for cooling by circulating inside air between an inner space of the rotating electric machine and an inner space of the air-cooled heat exchanger, The inside air of the axially central space of the machine is sucked radially outward through the axially central space of the air-cooled heat exchanger, and the sucked air is pressurized to form a shaft of the air-cooled heat exchanger. A blower for circulating inside air, which is pushed inward in the radial direction toward both end spaces in the axial direction of the rotary electric machine via the space at both ends of the rotating electric machine, is installed above the air-cooled heat exchanger, and the stator And said Axial ventilation holes are formed in the stator in the axial direction, cooling ventilation ducts are formed in the stator in the radial direction, and axial ventilation holes are formed in the rotor in the axial direction. And a cooling ventilation duct is formed along the radial direction.

Further, in the configuration of the present invention, the inside air circulation blower has a centrifugal blade, and the inside air pressurized by the centrifugal blade is provided in the heat exchanger frame by the air cooling heat exchange. It is characterized in that a flow straightening plate is provided to guide the space in both axial ends of the vessel.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a cooling structure for a rotating electric machine according to an embodiment of the present invention. The cooling structure of the present embodiment
The electric motor is air-cooled by a fully-closed other-force ventilation system. As shown in FIG. 1, an air-cooling heat exchanger 102 is mounted (mounted) on the upper surface of the electric motor 101, and a blower 131 for internal air circulation and a blower 132 for external air ventilation are connected to the air-cooling heat exchanger 102. ing.

In the electric motor 1, a stator 112 is installed on an inner peripheral surface of a frame 111, a rotor 114 is installed on a shaft 113, and the shaft 113 is rotatably mounted on a bracket 116 via a bearing 115. Supported.

An axial ventilation hole 112a is formed along the axial direction between the stator 112 and the frame 111, and the stator 112 has a cooling ventilation duct 112b extending along the radial direction.
Are formed. An axial ventilation hole 114a is formed in the rotor 114 along the axial direction, and a cooling ventilation duct 114b is formed in the radial direction.
At both ends of the blade 14, there are provided blade pieces 114 c for sending inside air to the stator 112 side.

The upper surface of the frame 111 is opened, and the internal space of the electric motor 101 and the internal space of the air-cooled heat exchanger 102 communicate with each other through this opening.

In the air-cooled heat exchanger 102, one end face 121a and the other end face 1a of the box-shaped heat exchanger frame 121 are provided.
A number of pipes 122 each having an elliptical cross-sectional shape are attached so as to pass through 21b.
In the heat exchanger frame 121, two baffles (baffles) 123a and 123b are arranged, and the space inside the heat exchanger frame 121 has three rooms 124a and 124.
b, 124c.

The outside air ventilation blower 132 sucks in outside air (indicated by a dotted arrow in the figure), and supplies the outside air to the left end face of each pipe 122 through the ventilation cover 133.
For this reason, the outside air flows through the internal space of each pipe 122 and the exhaust cover 134 extends from the right end face of each pipe 122.
Exhausted through In this way, by allowing the outside air to flow through the space inside the pipe, the heat exchanger frame 12
The inside air (indicated by a solid line arrow in the figure) in the internal space of the first embodiment can be air-cooled.

The inside air circulation blower 131 is disposed above the heat exchanger frame 121 of the air-cooled heat exchanger 102 and at the center in the axial direction. That is, the central room 124
It is arranged to be located directly above b. This inside air circulation blower 131 has centrifugal blades 131a,
When the centrifugal vanes 131a rotate by driving, the inside air (air) in the room 124b is sucked radially outward, and the sucked inside air is pressurized by the centrifugal vanes 131a and pushed toward both ends in the axial direction. To rooms 124a and 124c.

In the heat exchanger frame 121, there is provided a rectifying plate 135 that guides the inside air pressurized by the centrifugal blades 131a to the chambers 124a and 124c on both sides in the axial direction to smoothly send the inside air.

When the blower 131 for inside air circulation drives and the centrifugal blade 131a rotates, the inside air in the space in the center part in the axial direction of the electric motor 101 passes through the room 124b in the center part in the axial direction of the air-cooled heat exchanger 102. Then, it is sucked radially outward (that is, toward the rotation center of the centrifugal blade 131a). The sucked inside air is pressurized by the centrifugal blades 131a and pushed toward both ends in the axial direction, and is pushed inward in the radial direction through the chambers 124a and 124c at both ends in the axial direction. Into the space at both ends in the direction.

The inside air sent into the space at both ends in the axial direction of the electric motor 101 flows to the axial center of the electric motor 101 through the axial ventilation holes 112a and 114a, and also flows through the cooling air ducts 114a and 112b. To cool the electric motor 101.

The inside air flowing through the room 124b and the rooms 124a and 124c of the air-cooled heat exchanger 102 touches the pipe 2 and is cooled.

As described above, the inside air rises radially outward at the center in the axial direction, and is then blown by the blower 1 for inside air circulation.
31 and is diverted to the left and right.
The electric power is supplied to both end spaces of the electric motor 1 via the both end spaces in the axial direction. Therefore, since the inside air cooled to substantially the same temperature is supplied to the space at both ends of the electric motor 1, the electric motor 1
The temperature difference between the two ends is eliminated. As described above, since the temperature gradient on the left and right of the electric motor 1 is eliminated, the maximum temperature of the electric motor 1 is reduced, and the reliability of the electric motor 1 is increased.

The inside air sent into the space at both ends in the axial direction of the electric motor 101 is subjected to the axial ventilation holes 112a, 114a.
a to the axial center of the electric motor 101 through
The electric motor 10 is connected via the cooling ventilation ducts 114a and 112b.
1, and the electric motor 101 can be cooled reliably.

Further, since the inside air is divided into two directions, the ventilation path is shortened and the ventilation resistance is reduced. As a result, a small size air blower 131 can be employed.

Further, since the current plate 135 is provided,
The inside air sent from the inside air circulation blower 131 can be smoothly sent to the chambers 124a and 124c on both sides in the axial direction, and the cooling efficiency is improved.

It is needless to say that the present invention can be applied not only to a motor but also to a generator.

[0032]

As described in detail with the above embodiments, in the present invention, the inside air is sucked from the axially central space of the rotating electric machine, cooled by the air-cooled heat exchanger, and Since the air is fed into the spaces at both ends in the direction, the temperature difference between the left and right of the rotating electric machine is eliminated, the maximum temperature of the rotating electric machine is reduced, and the reliability of the rotating electric machine is increased.

The inside air sucked into the air-cooled heat exchanger is
Since the air is diverted in the direction, the ventilation path is shortened, and the ventilation resistance is reduced. As a result, a small-sized air circulation fan can be employed.

Further, the inside air sent out from the centrifugal blades of the inside air circulation blower can be guided by the straightening vanes and smoothly sent to both axial end spaces of the air-cooled heat exchanger.
Cooling efficiency is improved.

Also, the inside air sent into the space at both ends in the axial direction of the motor flows in the axial center of the motor through the axial ventilation holes, and flows in the radial direction of the motor through the cooling ventilation duct. Can be cooled reliably.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a cooling structure of a rotating electric machine according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing a conventional cooling structure of a rotating electric machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Motor 11 Frame 11a, 11b Opening 12 Stator 12a Axial ventilation hole 13 Shaft 14 Rotor 14a Axial ventilation hole 15 Bearing 16 Bracket 2 Air-cooled heat exchanger 21 Heat exchanger frame 21a One end face 21b Other end face 22 Pipe 23a , 23b, 23c Baffle 24a to 24d Room 25a, 25b Opening 31 Inside air circulation fan 32 Outside air ventilation fan 33 Ventilation cover 34 Air duct 101 Motor 111 Frame 112 Stator 112a Axial ventilation hole 112b Cooling ventilation duct 113 Shaft 114 Rotor 114a Axial ventilation hole 114b Cooling ventilation duct 115 Bearing 116 Bracket 102 Air-cooled heat exchanger 121 Heat exchanger frame 121a One end face 121b Other end face 122 Pipe 123a, 1 23b Baffle 124a-124c Room 131 Inside air circulation blower 131a Centrifugal blade 132 Outside air ventilation blower 133 Ventilation cover 134 Exhaust cover 135 Rectifier plate C1, C2 Coil temperature

Claims (2)

[Claims] 1. An air-cooled heat exchanger formed by penetrating a heat exchanger frame through a plurality of pipes through which outside air flows in a space inside the pipe is mounted on an upper surface of a rotating electric machine, and the inside air is removed by the rotating electric machine. In the cooling structure of a rotary electric machine that cools by circulating and circulating between the internal space of the rotary electric machine and the internal space of the air-cooling heat exchanger, Via the central space in the axial direction of the vessel, sucking in the radially outward direction, pressurizing the sucked air, and passing through the space at both axial ends of the air-cooled heat exchanger, the shaft of the rotating electric machine. At the top of the air-cooled heat exchanger, a blower for inside air circulation that is pushed inward in the radial direction toward the space at both ends in the direction is provided. Forming a hole A rotating air duct formed in the stator along the radial direction, a cooling air duct formed in the rotor along the axial direction, and a cooling air duct formed along the radial direction; Machine cooling structure. 2. The inside air circulation blower has centrifugal blades, and inside the heat exchanger frame, the inside air pressurized by the centrifugal blades is provided at both axial ends of the air-cooled heat exchanger. A cooling structure for a rotating electric machine, wherein a rectifying plate is provided to guide the internal space.