JPH06261500A - Electric rotating machine - Google Patents

Abstract

PURPOSE:To enhance cooling effect while decreasing windage loss and to realize downsizing of electric rotating machine by disposing a gas cooler and a fan in an enclosed electric rotating machine and circulating cooling gas by means of various ducts and windbreaks thereby cooling the heating parts, e.g. stator core, stator winding, rotor core. CONSTITUTION:A gas cooler 11 is disposed in the casing 1 for an enclosed electric rotating machine while a fan 9 is fixed to the rotor shaft 8 and cooling gas is circulated while branching as shown on the drawing. A part of the cooling gas passes through a vent 19, a part of a plurality of radial ventilation ducts 3 of stator core 2, a gap 5 between the core 2 and the stator core 7, other ventilation ducts 3, an outer windbreak 13, a duct 14, and the fan 9 to be returned to the gas cooler. Another part of cooling gas passes through a vent 20 and cools the stator winding 4 and passes through the ventilation duct 3 to the outer windbreak 13 thence passes through the duct 14 to be returned back to the fan 9. This structure cools each heating part effectively while decreasing windage loss thus allowing downsizing of electric machine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary electric machine equipped with an internal cooling device, and more particularly, to a stator core, and a ventilating air flowing to a stator core and an end of the core after a stator cooling gas is given dynamic pressure by a fan. The present invention relates to a rotating electric machine having a path.

[0002]

2. Description of the Related Art In rotating electric machines, particularly large rotating electric machines such as turbine generators, the temperature of the stator windings, the stator core, etc. rises due to electrical and mechanical losses. In particular, the temperature rise at the end of the stator core is remarkable. In a rotating electric machine, in order to cool these temperature rising parts, a fan attached to a rotor circulates gas inside a generator and cools it with a gas cooler. A conventional cooling system for a rotary electric machine will be described below with reference to FIG. FIG. 2 is a sectional view of the rotating electric machine disclosed in Japanese Patent Laid-Open No. 53-29509. The cooling gas in the machine is pressure-fed to the end portion of the stator by the fan 9 to cool the stator core 2, its end portion, and the rotor 6. After that, the warmed gas passes through the exhaust section of the stator core 2 and the gas cooler.
After reaching 11 and being cooled, it reaches the fan 9.

[0003]

By the way, in this conventional cooling system, the cooling gas cooled by the cooler 11 passes through the fan 9 before reaching the stator core 2 portion for cooling, and the fan 9 There is a problem in that the temperature of the cooling gas rises due to the loss caused by. Further, the fan 9 has an inner oil drain 15 outside the axial machine to prevent the lubricating oil in the bearing chamber from entering the generator, but the section between the fan 9 and the inner oil drain 15 has a cooling gas In the air passage, the pressure is negative because it is on the inflow side to the fan 9, and there is a problem that the oil in the bearing chamber is drawn into the machine.

As a means for solving the above-mentioned problems, Japanese Patent Laid-Open No.
The reverse-flow cooling rotating electric machine disclosed in No. -15303 is known, but the reverse-flow cooling rotating electric machine is structurally complicated, unlike the conventional cooling structure, and cools the end of the stator core. Since the cooling gas is the cooling gas that has cooled the other parts of the stator, there is a problem that the temperature has already risen and the cooling efficiency is not good.

Therefore, in the present invention, the cooling gas is passed through the fan 9 and then the gas cooler 11 to enhance the cooling effect of the generator as a whole, and the fan 11 and the oil inside Apply positive pressure to the section between the cuts 15,
In addition, the ventilation passage for the cooling gas after passing through the gas cooler 11 is branched in parallel to the ventilation passage for cooling the stator core 2 part and the ventilation passage for cooling the stator core end portion, so that the stator core end portion The purpose is to make the cooling method as good as the conventional one.

[0006]

In order to achieve the above object, the present invention proposes a rotating electric machine having the following cooling air passage. That is, in the present invention, a casing containing a cooling gas, a stator including a stator iron core having a plurality of radial cooling passages axially spaced in the casing, and a stator core A rotor rotatably supported on the inner peripheral side through a gas gap and having a fan at its shaft end, and a gas cooler arranged on the end side of the stator core in the casing, First ventilation passage forming means, which is disposed in the casing and between the gas cooler and the fan, and guides the cooling gas, which has been given a dynamic pressure by the fan, to the gas cooler; and the stator core. Second ventilation passage forming means for guiding the cooling gas cooled to the fan to the fan, and third ventilation passage forming means for guiding the cooling gas passing through the gas cooler to the radial cooling passage of the stator core, and the same cooling Gas is applied to the stator core end, etc. Characterized in that provided between the fourth air passage forming means for guiding.

[0007]

By configuring the cooling ventilation passage as described above, the cooling gas, which is given a dynamic pressure by the fan, blows out in the axial direction outside the generator, that is, in the direction with the bearing bracket and the inside oil drainer, and the outside windshield plate. It goes through the section surrounded by the bearing bracket and reaches the gas cooler. The cooling gas cooled by the gas cooler separately flows into the intake section of the stator core and the section surrounded by the end of the stator core and the inner windbreak plate. The cooling gas that has flowed into the intake section of the stator core passes through the ventilation duct of the intake section of the stator core, passes through the gas gap between the stator core and the rotor, and then flows into the exhaust section of the stator core. After passing through the ventilation duct, it enters the section surrounded by the inner windshield and the outer windshield through the air guide to reach the fan. The cooling gas flowing into the section surrounded by the end portion of the stator core and the inner windbreak plate partially flows into the rotor, cools the rotor and joins the exhaust section of the stator core, and the others After cooling the ends of the stator core, they join the exhaust section of the stator core. That is, since the cooling gas that cools the central portion of the stator core and the end portions of the stator core passes through the gas cooler after passing through the fan, the cooling gas cooled by the gas cooler as in the conventional example does not cool. The temperature does not rise due to the loss of the fan that passes through the fan before it reaches the stator core.
Further, since the section between the fan and the inner oil drainer is on the outflow side from the fan, a positive pressure is applied, so that oil in the bearing chamber is not drawn into the machine unlike the conventional example. Further, by providing the ventilation passage for cooling the stator core end portion in parallel with the ventilation passage for cooling the stator core portion, the cooling of the stator core end portion is not lowered as compared with the conventional example.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG. A stator core 2 is arranged in a stator casing 1, and a plurality of radial ventilation ducts 3 are formed axially spaced from each other in the stator core 2 so that a cooling gas can flow therethrough. Further, the stator winding 4 is inserted in the axial slot (not shown) of the stator core 2. A rotor 6 is provided in an inner peripheral portion of the stator core 2 through a gas gap 5.
Is rotatably arranged, and the rotor 6 is composed of an iron core portion 7 around which a winding is wound, and a shaft portion 8 rotatably supported through a bearing metal 16, and near the end portion of the shaft portion 8. A fan 9 composed of a plurality of blades is formed in the shaft portion 8, the iron core portion 7, and a joint portion for holding a winding portion at a joint portion.
Is provided. A bearing bracket 10 is provided at an end of the stator casing 1 to surround the stator end and the rotor end, and a gas cooler 11 is arranged and fixed at a predetermined position inside the bearing bracket 10. ing. A fan 9 is installed between the fan 9 and the gas cooler 11.
An outer windbreak plate 12 is provided so that the gas sent from is guided to the cooler 11, and an inner windbreak plate 13 is provided to partition the gas for cooling the end of the iron core and the gas flowing into the fan after cooling. . The outlet side of the gas cooler 11 is provided with a sub-chamber 18, the sub-chamber 18 is provided with a ventilation path 19 for connecting the intake section of the stator core 2, and the sub-chamber 18 is provided with an end portion of the stator core 2. An air passage 20 is provided to connect the section surrounded by the inner windbreak plate 12. Inner windshield 13 to separate the intake and exhaust sections of the stator core 2
Is provided, and an air guide 14 is provided to connect the exhaust section and the exhaust section of the stator core 2, and the section surrounded by the inner windbreak plate 12 and the outer windbreak plate 13 and the exhaust section. An internal oil drain 15 is provided between the bearing bracket 10 and the rotor 6 to prevent lubricating oil from the bearing chamber from entering the generator.

According to this embodiment, the cooling air passage has the following structure. That is, the cooling gas to which the dynamic pressure is given by the fan 9 is blown out in the generator axial direction outside the machine, that is, in the direction in which the bearing bracket 10 and the inner oil drainer 15 exist, and the section surrounded by the outer windshield 12 and the bearing bracket 10 is discharged. It passes through and reaches the gas cooler 11. The cooling gas cooled by the gas cooler 11 flows into the intake section of the stator core 2 through the ventilation passage 19 and the ventilation passage.
It passes through 20 and is divided into an end portion of the stator core 2 and a section surrounded by the inner windbreak plate 13. The cooling gas flowing into the intake section of the central portion of the stator core passes through the ventilation duct 3 of the intake section of the stator core 2, passes through the ventilation duct 3 of the exhaust section of the stator core 3, and passes through the stator core section. After cooling, it passes through the wind guide 14 and the inside windshield 13 and outside windshield 12
Enter the section surrounded by and reach fan 9. A part of the cooling gas that has flowed into the section surrounded by the ends of the stator core 2 and the inner windshield 13 flows from the retaining ring 17 of the rotor 6 to cool the rotor 6 and cool the stator core 2 Of the stator core 2 is cooled, and the other ends are joined to the exhaust section of the stator core 2.

By forming the cooling air passage as described above, the cooling gas for cooling the stator core 2 passes through the fan 9 and then the gas cooler 11, so that the gas cooler 11 can be used as in the conventional case. The cooled cooling gas does not pass through the fan 9 before reaching the stator core 2 part for cooling and the temperature does not rise due to the loss of the fan 9. Also,
Since the section between the fan 9 and the inner oil drainer 15 is on the outflow side from the fan 9, it becomes a positive pressure and the fan 9
Since the section between the inner oil drainer 15 and the inner oil drainer 15 is on the inflow side to the fan 9, a negative pressure is created and the oil in the bearing chamber is never drawn into the generator. In addition, the ventilation passage for the cooling gas after passing through the gas cooler 11 is branched in parallel to the ventilation passage for cooling the two stator core portions and the ventilation passage for cooling the end portions of the stator core, thereby providing the most cooling. Even for the end portions of the stator core that need to be considered, a cooling effect comparable to that of the conventional example can be obtained.

[0011]

As described above, according to the present invention, the cooling effect of the entire generator is enhanced by passing the cooling gas ventilation passage through the fan and then the gas cooler.
In addition, the section between the fan and the oil drainer is set to positive pressure, and the ventilation passage for the cooling gas after passing through the gas cooler is used as the ventilation passage for cooling the stator core and the ventilation passage for cooling the stator core end. By branching in parallel, the cooling effect of the end portions of the stator core can be made equal to that of the conventional example.

According to the present invention, since it is possible to enhance the cooling effect of the generator, it is possible to reduce the size and weight of the generator. Further, since the cooling effect is improved, the air volume can be reduced, and the wind loss can be reduced, so that the efficiency of the generator can be increased.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a cooling system for a rotating electric machine according to the present invention.

FIG. 2 is a cross-sectional view showing a cooling system for a conventional rotary electric machine.

[Explanation of symbols]

 1 ... Casing 2 ... Stator core 3 ... Ventilation duct 4 ... Stator winding 5 ... Gas gap 6 ... Rotor 7 ... Rotor core part 8 ... Rotor shaft part 9 ... Fan 10 ... Bearing bracket 11 ... Gas cooler 12 ... Outside windbreak plate 12a ... Windproof plate 13 ... Inside windbreak plate 14 ... Wind guide 15 ... Inner oil drainer 16 ... Bearing metal 17 ... Holding ring 18 ... Room 19 ... Ventilation path 20 ... Ventilation path

Claims (1)

[Claims] 1. A stator core having a plurality of radial cooling passages arranged in a casing in which a cooling gas is sealed, and a stator core rotatably supported on an inner peripheral side of the stator core through a gas gap, and A rotor having a fan at its shaft end, a gas cooler arranged on the end side of the stator core in the casing, and in the casing and between the gas cooler and the fan. First ventilation passage forming means provided for guiding the cooling gas to which a dynamic pressure is applied by the fan to the cooler, and second guiding means for guiding the cooling gas passing through the gas cooler to the radial cooling passage of the stator core. A ventilation path forming means,
A third ventilation passage forming means for guiding the cooling gas to the end portion of the stator core and a fourth ventilation passage forming means for guiding the cooling gas that has cooled the stator core to the fan are provided. Rotating electric machine.