JP2652147B2 - Electric blower for gas insulated transformer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric blower for circulating cooling gas used in a gas-insulated transformer.

[0002]

2. Description of the Related Art An electric blower for a gas-insulated transformer which has been already put into practical use is configured as shown in FIG.

[0003] That is, in FIG.
A motor casing (2) is fixed to (1), and a bearing (3) and a stator (4) are installed in the motor casing (2).
A rotating shaft (5) is supported via a bearing (3), and a rotor (6) and an impeller (7) are fixed to the shaft end on the rotating shaft (5). The gasket (8) keeps the blower casing (1) and the motor casing (2) airtight from the outside atmosphere. The gas discharged from the blower cools the transformer by circulating through a cooler and a transformer (not shown), as indicated by white arrows.

In the above-described electric blower, an external fan for cooling the electric motor cannot be provided in order to maintain airtightness with respect to the outside atmosphere.
The motor is cooled by natural heat radiation from the motor casing (2) attached with (9). Therefore, there is a problem that the stator (4) and the rotor (6) must be several times larger than usual in order to minimize the heat generated by the motor.

To solve this problem, Japanese Unexamined Utility Model Publication No. Hei 3-102091 discloses a motor casing having a double structure, in which gas is circulated inside a motor through a gap between a motor stator and a rotor. It is intended to improve cooling. However, in this case, the gap between the motor stator and the rotor is very small, so that the gas flow cannot be increased, and the cooling effect is low, so that the effect of miniaturization is small, which is not practical.

[0006]

In any of the above means, the size of the stator and the rotor of the electric motor cannot be reduced. An object of the present invention is to provide an electric blower for a gas-insulated transformer in which the dimensions of a stator and a rotor of an electric motor are reduced.

[0007]

In order to achieve the above object, according to the present invention, in a motor-driven blower for circulating cooling gas for a gas-insulated transformer in the transformer, a motor stator is provided on a motor casing. And a plurality of spaces formed between the ribs and the stator are divided into an inflow path to the non-load side space and an outflow path from the non-load side space, and the load side inflow is A windbreak plate is provided between the road ribs to close off the load side space, and an outer peripheral side hole communicating with the bearing bracket on the motor load side from the outer periphery of the impeller of the blower to the inflow path through an external space, and a blade. An inner peripheral hole communicating with the outflow passage is provided in a main plate hole provided in the vicinity of the inner periphery of the vehicle.

[0008]

Since the present invention is constructed as described above, a part of the gas blown by the blower is circulated inside the motor to forcibly cool the motor, so that the rotor and the stator are miniaturized. It is possible to divide the gas flow into inflow and outflow in a plurality of spaces formed between the stator and the ribs as a circulation path, so that the amount of gas circulating inside can be increased, And the effect of downsizing the stator is very high.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. The motor bearing bracket (10) is fixed to the blower casing (1).
The motor casing (2) is fixed to (10). The bearing (3) is installed on the bearing bracket (10). Motor casing
In (2), a stator (4) is installed via a plurality of axial ribs (11). A rotating shaft (5) is supported via a bearing (3), and a rotor (6) and an impeller (7) are fixed to the shaft end on the rotating shaft (5). Blower casing (1) and motor casing
(2) is kept airtight to the outside atmosphere by the gasket (8). The space formed between the rib (11) and the stator (4) is an inflow passage through which gas flows into the non-load-side space (12) of the motor.
(13) and an outflow path (14) from the non-load-side space (12), and between the load-side inflow path ribs, the load-side space (15) is blocked (a slit may be provided). An outer peripheral hole (18) communicating with the inflow passage (13) from the outer periphery of the impeller of the blower to the bearing bracket (10) on the electric motor load side through the external space (17) is provided. And an inner peripheral side hole (20) communicating with the outflow passage (14) in a main plate hole (19) provided near the inner periphery of the impeller. still,
(21) is an arrow indicating a motor cooling gas flow. Also, (22)
Is a blower suction port, (23) is a blower discharge port, and (24) is an arrow indicating a gas main flow.

Next, the operation of the above embodiment will be described.
By operating the electric blower, the main gas flow (24) flows from the blower inlet (22) to the blower outlet (23). Impeller
Since the gas pressure on the outer periphery of (7) is higher than that on the inner periphery, a part of the gas main flow (24) is, as shown in the motor cooling gas flow (21),
From the outer peripheral side hole (18) provided in the bearing bracket (10), the motor passes through the inflow path (13), the non-load side space (12), the outflow path (14), the load side space (15), and From the inner peripheral hole (20) provided in the bracket (10), through the main plate hole (19), the impeller
Go to the inner circumference side of (7) and cool the motor vigorously. Therefore, the rotor (6) and the stator (4) of the motor can be significantly reduced in size.

[0011]

As described above, according to the present invention,
In an electric blower that circulates the cooling gas of a gas-insulated transformer into the transformer, a part of the gas blown by the blower is circulated inside the motor, thereby forcibly cooling the motor. It is possible to reduce the size of the gas flow, and to divide the gas flow into the inflow and outflow flows in a plurality of spaces formed between the motor stator and the ribs as the circulation path, so that the amount of gas circulating inside is increased. Accordingly, it is possible to provide an electric blower for a gas-insulated transformer in which the rotor and the stator are significantly reduced in size.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of an electric blower for a gas-insulated transformer according to the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is a sectional view taken along the line III-III in FIG. 1;

FIG. 4 is a longitudinal sectional view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Blower casing 2 ... Electric motor casing 3 ... Bearing 4 ... Stator 5 ... Rotating shaft 6 ... Rotor 7 ... Impeller 8 ... Gasket 9 ... Cooling fin 10 ... Bearing bracket 11 ... Rib 12 ... Non-load side space 13 ... Inflow Road 14 Outflow path 15 Load side space 16 Windproof plate 17 External space 18 Outer hole 19 Main hole 20 Inner hole 21 Motor cooling gas flow 22 Blower inlet 23 Blower outlet 24 ... Gas mainstream

Claims (1)

(57) [Claims] In an electric blower for circulating a cooling gas of a gas-insulated transformer in a transformer, an electric motor stator is fixed to a plurality of axial ribs provided on an electric motor casing, and the rib is fixed between the rib and the stator. The formed spaces are divided into an inflow path to the non-load-side space and an outflow path from the non-load-side space, and a windbreak plate is provided between the load-side inflow path ribs to block off the load-side space. An outer peripheral side hole communicating with the inflow passage from the outer periphery of the impeller of the blower to the bearing bracket on the motor load side through an external space; and an inner peripheral side communicating with the main plate hole provided near the inner periphery of the impeller from the outflow passage. An electric blower for a gas-insulated transformer, characterized by having holes.