JPH09285046A - Dynamo-electric machine and its stator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the length of a stator core in its axial direction by a method wherein ventilation paths by which the stator core and the rotor of a dynamo-electric machine are cooled are so provided in the stator core as to penetrate the stator core from its inner side teeth part to its outer part. SOLUTION: A rotor is inserted into the inside of the cylindrical stator core 21 of the dynamo-electric machine so as to rotate freely. A large number of ventilation holes 3 which are ventilation paths necessary for cooling the stator core 21 and rotor of the dynamo-electric machine are so provided in the stator core 21 as to penetrate the stator core 21 from its inner side teeth part to its outer part. Slots 22 which are trenches whose depth directions are the radial directions of the stator core 21 and whose longitudinal directions are the rotary shaft direction of the rotor are provided in the cylindrical inside surface of the stator core 21. A plurality of the slots 22 are provided in the rotating direction of the rotor and stator coils 2 are provided in the respective slots 22. With this constitution, the stator core 21 is not divided by the ventilation holes and necessary flux can be obtained efficiently and the axial direction length of the dynamo-electric machine is shortened.

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 and a stator thereof, and more particularly to a rotary electric machine and a stator thereof improved in a cooling system of a turbine generator or a stator coil fixing system.

[0002]

2. Description of the Related Art Rotating electric machines are used in electric motors, generators, etc. In particular, large rotating electric machines used in turbine generators, etc. The temperature of the stator core, rotor, etc. rises.

Further, in the stator, the temperature rise at the end of the iron core is particularly 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 method for a rotary electric machine will be described below with reference to FIGS. 2 and 3.

FIG. 3 is a sectional view of a rotary electric machine showing an embodiment of a conventional cooling system for a rotary electric machine. FIG. 4 is a cross-sectional perspective view of a stator showing an embodiment of a cooling system for a conventional rotary electric machine. FIG.
As shown in, the cooling gas inside the machine is cooled by the gas cooler 11 and then sent under pressure by the fan 13 to the end portion of the stator. The pressure-fed cooling gas is supplied to the back of the stator core, that is, to the outer side of the stator core, gas g1, to the end of the stator core, g2, to the end of the rotor, g3, and to the rotor. The gas g4 is sent to the gas gap between the stator and the stator.

Of these, the gas g1 sent to the back of the stator core, that is, the outer side of the stator core 1, is sent from the back of the core of the stator intake section to the gas gap 7 through the ventilation holes 4.

Thereafter, in the case where the rotor cooling system is of a type in which gas is taken from the rotor surface into the rotor, it is further sent to the inside of the rotor to cool the rotor and sent to the gas gap 7 again. Through the ventilation duct 4 to the back of the iron core of the stator exhaust section and then back to the gas cooler 11 through the air guide 12.

As described above, the ventilation duct 4 plays an important role in forming a cooling ventilation path in the central portion of the stator core 1 of the rotating electric machine and in the core portion of the rotor 5. Conventionally,
As a method of forming the ventilation duct 4, for example, as disclosed in Japanese Examined Patent Publication No. 61-11064, a laminated iron core is axially divided as shown in FIG. 4, and a spacing piece 14 is sandwiched between them. Was going by.

[0008]

Such ventilation ducts 4 are required at predetermined intervals in consideration of cooling of the entire rotary electric machine. However, in the conventional cooling system for a rotary electric machine as shown in FIG. 4, magnetic flux does not pass through the ventilation duct 4 of the stator core 1.

Therefore, from the viewpoint of securing the magnetic flux necessary for the rotating electric machine, the ventilation duct 4 is a useless space, and since there is the ventilation duct 4, it is necessary to increase the axial length of the entire stator. there were. Further, since the temperature rise of the end portion is the largest as described above, it cannot be said that the cooling method is necessarily efficient from the viewpoint of cooling only the stator core 1.

On the other hand, when fixing the stator coil 2 to the stator core 1, in order to fix the stator coil 2 and to secure sufficient heat transfer between the stator coil 2 and the stator core 1, the two are fixed. There is a demand for close contact and sufficient fixation.

Therefore, for example, a liquid substance such as a resin is injected between the stator coil 2 and the stator core 1 and then solidified by heat or the like to fix the stator coil 2 to the stator core 1. It is possible.

However, in the conventional rotating electric machine, since the liquid substance flows out from the ventilation duct 4 of the stator core 1, it is impossible to use such a substance. Therefore, as a method of housing the stator coil 2 in the stator iron core 1 and fixing it, a method as shown in FIG. 5 has been generally used in the case of a rotating electric machine, particularly a large-sized turbine generator.

FIG. 5 is a sectional view of a stator showing a conventional embodiment. In FIG. 1, the stator coil 2 has a structure in which a conductive material such as copper is covered with an insulating material, and the stator coil 2 is housed in the slot of the stator core 1.

With respect to the electromagnetic vibration of the stator coil 2, the ripple spring 1 with respect to the vibration in the width direction of the slot.
5, the vibration in the depth direction of the slot is suppressed by the stator wedge 17.

However, even in the case of this structure, the electromagnetic vibration suppressing effect is insufficient as compared with the case, and between the stator coil 2 and the stator core 1 where the ripple spring 15 is inserted. However, there was a problem that the heat conduction of the product deteriorated.

The present invention has been made in consideration of such circumstances, and a first object thereof is to efficiently obtain a magnetic flux while ensuring the cooling required for a rotating electric machine, and thus the entire stator. An object of the present invention is to provide a rotating electric machine and a stator thereof that can reduce the axial length.

A second object is to improve the vibration suppressing effect of the stator coil and to improve the thermal conductivity for cooling the stator coil while ensuring the cooling required for the rotating electric machine. To provide a rotating electric machine.

[0018]

The gist of the present invention is to propose a rotating electric machine having the following stator cooling air passages. That is, as shown in FIG. 1, the ventilation path of the stator core 1 required for cooling the stator core 1 and the rotor 5 of the rotating electric machine is provided from the teeth portion on the inner diameter side of the stator core 1 to the stator core 1. It is configured by providing a ventilation hole 3 penetrating to the back part of the. With such a configuration, it is not necessary to provide a ventilation duct as in the conventional case, so that the occupation ratio of the stator core 1 in the stator is increased and the axial length of the stator core 1 is shortened. You can

Further, as a method for housing and fixing the stator coil 2 in the stator core 1 by configuring the ventilation path as described above, the stator core 1 without using the ripple spring 15 as shown in FIG. It is possible to adopt a configuration in which a resin or the like is injected into the slot. With such a configuration, the vibration suppressing effect of the stator coil 2 and the thermal conductivity for cooling can be improved.

Further, the solution of the above problems is technically realized by the following solution means. First, the invention corresponding to claim 1 is a rotary electric machine in which a stator assembly including a stator core is arranged in an airtight casing in which a cooling gas is sealed, and a plurality of stator cores are provided in the axial direction, and The rotary electric machine is provided with a cooling passage for circulating the cooling gas in a radial direction and an axial groove for accommodating a conductor on an inner diameter side thereof, and the cooling passage is arranged without being connected to the groove. A stator assembly including a stator iron core is arranged in an airtight casing in which a cooling gas is sealed, a plurality of stator iron cores are provided in the axial direction, and cooling passages for circulating the cooling gas in the radial direction, respectively. In the rotating electric machine having an axial groove for accommodating the conductor on the inner diameter side thereof, the cooling passage is arranged without being connected to the groove.

The invention according to claim 2 is the rotating electric machine according to the invention according to claim 1, wherein a liquid which hardens the conductor housed in the groove by heat is solidified and fixed.

Further, the invention according to claim 3 is the rotary electric machine according to the invention according to claim 2, wherein the liquid which is hardened by heat is a resin. Furthermore, the invention according to claim 4 is the rotating electric machine according to the invention according to claim 1, in which a liquid that cures the conductor housed in the groove by drying is solidified and fixed.

On the other hand, the invention according to claim 5 is the invention according to claim 1, in which a solidifiable liquid is injected into the groove in which the conductor is accommodated, and the liquid is solidified to form the conductor. It is a rotating electric machine that is fixed.

According to a sixth aspect of the present invention, in a stator of a rotating electric machine in which a stator core is arranged in an airtight casing containing a cooling gas, a plurality of stator cores are provided in the axial direction, and A stator of a rotating electric machine, each of which is provided with a cooling passage for circulating cooling gas in a radial direction and an axial groove for accommodating a conductor on an inner diameter side thereof, the cooling passage being arranged without being connected to the groove.

Further, the invention according to claim 7 includes an airtight casing enclosing a cooling gas, and a stator core arranged in the casing and having therein a plurality of radial cooling passages provided in the axial direction. A stator assembly, a rotor rotatably supported by an inner peripheral portion of the stator core via a gas gap therebetween, and a gas cooler arranged in a casing. A rotary electric machine in which an axial groove for accommodating a conductor is provided on the inner diameter side of an iron core, and the radial cooling passage does not interfere with the inner diameter side axial groove.

Furthermore, the invention corresponding to claim 8 is
In a rotary electric machine in which a stator assembly including a stator iron core is arranged in an airtight casing in which a cooling gas is sealed, a plurality of stator iron cores are provided in the axial direction, and each of the stator iron cores has a predetermined size for circulating the cooling gas in the radial direction. The rotating electric machine includes a cooling passage having an opening of a size. (Operation) First, in the rotating electric machine and the rotor of the invention according to claims 1, 6, 7 and 8, the cooling passage for circulating the cooling gas in the radial direction has an axial direction in which the conductor is housed on the inner diameter side. It is arranged without connecting to the groove.

Therefore, since it is not necessary to provide a ventilation duct as in the prior art, the occupation ratio of the stator core in the stator is increased and the axial length of the stator core can be shortened.

Next, in the rotating electric machine of the invention according to claims 2 to 5, the same operation as that of the invention according to claim 1 is achieved, and a solidifiable liquid is injected into the groove containing the conductor. Then, the liquid is solidified and the conductor is fixed.

This is possible because the cooling passage is not connected to the groove. That is, when the cooling passage is connected to the groove, the liquid flows out through the cooling passage to the outside as described in the related art.

In the present invention, since the cooling passage and the groove are not connected to each other, the liquid can be prevented from flowing out and the conductor can be solidified by the solidifiable liquid.
Therefore, the effect of suppressing the vibration of the conductor such as the stator coil,
And the thermal conductivity for cooling can be improved.

In the inventions corresponding to claims 2 and 3, a liquid such as a resin which is hardened by heat is used. Further, in the invention corresponding to claim 4, a liquid which is cured by drying is used.

[0032]

Embodiments of the present invention will be described below in detail with reference to the drawings. (First Embodiment of the Invention) FIG. 1 is a sectional perspective view showing an example of a stator in a rotary electric machine according to a first embodiment of the present invention.

The stator according to the present embodiment shown in the figure is applied to the conventional rotary electric machine shown in FIG. Here, the same parts as those of the conventional apparatus shown in FIG. Further, the entire ventilation path inside the rotary electric machine is the same as that in FIG. 3, and therefore detailed description thereof will be omitted.

In this rotating electric machine, the stator iron core 21 is formed in a cylindrical shape, and the rotor 5 shown in FIG. 3 is inserted into the space inside the cylindrical portion. In addition, as a ventilation path for the stator core 21 of the rotating electric machine and the stator core 21 required for cooling the rotor 5, the stator core 21
A plurality of ventilation holes 3 are provided as a plurality of cooling passages penetrating from the teeth portion on the inner diameter side of the stator core 21 to the back portion of the stator core 21.

Furthermore, inside the cylindrical portion of the stator core 21,
A slot 22 is provided as a groove whose outer direction is the depth direction and whose rotational axis direction is the length direction. A plurality of slots 22 are provided in the rotating direction of the stator core 21, and the stator coil 2 is provided in each slot 22.

The shape of the vent holes 3 is a polygon such as a circle, an ellipse, or a quadrangle, and the size of the holes is smaller than the interval of the slots 22 in the rotational direction. . The ventilation holes 3 are arranged so as not to be connected to the slots 22.

As for the area and the number of the ventilation holes 3, a number that can sufficiently cool the rotary electric machine is secured.
Next, in the rotary electric machine according to the embodiment of the present invention configured as described above, cooling is performed by flowing the cooling gas through the ventilation path described in FIG.

Here, the radial ventilation passages of the stator core 21 are formed by the ventilation holes 3 shown in FIG. 1 instead of the ventilation ducts 4 shown in FIG. Further, the ventilation holes 3 are
It is not necessary to provide a ventilation duct that divides the stator core 21, and the required magnetic flux can be efficiently obtained.

As described above, according to the rotary electric machine of the embodiment of the present invention, the stator core 21 is divided because the ventilation holes 3 are provided in the stator core 21 to secure the ventilation passage of the cooling gas. Since it is not necessary to provide the ventilation duct 4, therefore, the occupation ratio of the stator core in the stator is increased, the magnetic flux required for the rotating electric machine is efficiently secured, and the axial length of the stator core 21 is shortened. You can

This makes it possible to reduce the axial length of the entire stator. Further, when the ventilation passage is formed as the ventilation hole 3, it is considered that the total ventilation area is reduced, the cooling gas flow rate is reduced, and the cooling performance is reduced as compared with the case of the conventional ventilation duct 4. In the above-mentioned stator, the largest loss occurs at the end of the stator core, so that it is only necessary to secure an appropriate area and number of ventilation holes 3 in the central part of the stator. Therefore, the stator core 21 is sufficiently cooled. The stator core end is cooled by the gas g2 sent to the stator core end and the gas g3 sent to the rotor end, as in the prior art shown in FIG.

In a rotating electric machine such as a large-sized turbine generator, a cooling medium such as water is supplied to cool the stator coil 2 to cool the stator coil 2. Since the cooling loss is small, the area and the number of the ventilation holes 3 can be reduced as compared with the rotating electric machine in which the cooling medium does not flow inside the stator coil 2.

Further, in the case of a rotary electric machine such as a large-sized turbine generator as described above, the number of the stator coils 2 can be designed to be small, so that the slot 2 on the inner diameter side of the stator core 21 is formed.
Since the distance between the slot 2 and the slot 2 can be made large, it becomes dimensionally easy to provide the ventilation hole 3.

That is, when considering the cooling of the entire rotary electric machine, it is necessary to provide an appropriate number of such ventilation holes 3 at appropriate positions. However, the set position, opening diameter and number of the ventilation holes 3 are set at the design stage. Since it can be freely adjusted, it is possible to minimize the occupancy shown in the stator core of the cooling passage while ensuring necessary cooling for each part of the rotating electric machine and the stator core 21.
It is possible to more reliably and effectively achieve the effects of the present embodiment described above. (Second Embodiment of the Invention) FIG. 2 is a sectional view of a stator core for explaining an example of a coil fixing method applied to a rotating electric machine according to a second embodiment of the present invention. The same portions will be denoted by the same reference numerals and the description thereof will be omitted, and only different portions will be described here. Further, the same parts as those of the conventional device shown in FIG.

The stator core 21 having the same ventilation holes 3 as in the case of the first embodiment is used in the stator of this embodiment. Further, in this stator, the stator coil 2 housed in the slot 22 is fixed by the solidified resin 16.

The resin 16 in a liquid state is injected into the slots 22 of the stator core 21, and is solidified by being heated after the injection, so that the stator coil 2 and the stator core 21 are fixed.

Vibration of the stator coil 2 in the depth direction of the slot 22 is suppressed by the stator wedge 17. In the rotary electric machine according to the embodiment of the present invention configured as described above, the stator coil in the stator is sufficiently fixed by the solidified resin 16, and the vibration due to the electromagnetic force is sufficiently suppressed.

Further, the resin 16 is in close contact with the stator coil 2 and the stator core 21, so that sufficient heat transfer between the stator coil 2 and the stator core 21 is ensured. As described above, according to the rotating electric machine according to the embodiment of the present invention, the stator core 21 is arranged so that the ventilation holes 3 and the slots 22 are not connected to each other, and the resin 16 that is a liquid is injected to solidify the resin 16. Since the stator coil 2 is fixed by the above, the same effects as those of the rotating electric machine according to the embodiment of the present invention can be obtained, and the vibration of the stator coil can be suppressed while sufficiently cooling the stator core. And the thermal conductivity for cooling the stator coil can be improved.

Therefore, compared to the case where the ripple spring 15 is inserted and the stator coil 2 is fixed as in the conventional case, the effect of suppressing electromagnetic vibration is increased because the stator coil 2 is sufficiently fixed. In addition, ripple spring 1
Since the gas layer between the stator coil 2 and the stator core due to the insertion of 5 is not generated, the thermal conductivity is improved and the cooling performance of the rotating electric machine is improved.

In the above embodiment, the resin is used as the substance fixed to the rotor coil 2 and injected between the iron cores 21. However, the present invention is not limited to this, and a thermosetting resin other than the resin is used. It is possible to use various liquids that can be solidified by any method such as heat resistance, dry-curability, and the like. Furthermore, the present invention is not limited to the above-mentioned respective embodiments, and can be variously modified without departing from the gist thereof.

[0050]

As described above, according to the present invention,
It is possible to provide a rotating electric machine and a stator thereof that can reduce the axial length of the entire stator by efficiently obtaining magnetic flux while ensuring the cooling required for the rotating electric machine.

Further, according to the present invention, it is possible to improve the vibration suppressing effect of the stator coil and to improve the thermal conductivity for cooling the stator coil while ensuring the cooling required for the rotating electric machine. A rotating electric machine can be provided.

[Brief description of drawings]

FIG. 1 is a sectional perspective view showing an example of a stator in a rotary electric machine according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a stator core illustrating an example of a coil fixing method applied to a rotating electric machine according to a second embodiment of the present invention.

FIG. 3 is a sectional view of a rotary electric machine showing an example of a conventional cooling system for a rotary electric machine.

FIG. 4 is a cross-sectional perspective view of a stator showing an example of a conventional cooling system for a rotating electric machine.

FIG. 5 is a cross-sectional view of a stator showing a conventional example.

[Explanation of symbols]

 2 ... Stator coil 3 ... Ventilation hole 5 ... Rotor 6 ... Rotor ventilation hole 7 ... Gas gap 8 ... Casing 9 ... Windproof plate 10 ... Bearing bracket 11 ... Gas cooler 12 ... Wind guide 13 ... Fan 16 ... Resin 17 … Stator wedge 21… Stator core 22… Slot

Claims (8)

[Claims] 1. A rotary electric machine in which a stator assembly including a stator core is arranged in an airtight casing containing cooling gas, wherein a plurality of stator cores are provided in the axial direction, and each of the cooling gas A rotating electrical machine comprising: a cooling passage that circulates in a radial direction; and an axial groove that accommodates a conductor on an inner diameter side thereof, wherein the cooling passage is arranged without being connected to the groove. 2. The rotating electric machine according to claim 1, wherein a liquid that hardens the conductor contained in the groove by heat is solidified and fixed. 3. The rotating electric machine according to claim 2, wherein the liquid that is cured by heat is a resin. 4. The rotating electric machine according to claim 1, wherein a liquid which cures the conductor contained in the groove by drying is solidified and fixed. 5. The rotating electric machine according to claim 1, wherein a solidifiable liquid is injected into the groove in which the conductor is housed, and the liquid is solidified to fix the conductor. 6. A stator of a rotating electric machine in which a stator core is arranged in an airtight casing containing cooling gas, wherein a plurality of the stator cores are provided in an axial direction, and each of the cooling gas is radially provided. A stator for a rotating electric machine, comprising: a cooling passage for circulation; and an axial groove for accommodating a conductor on an inner diameter side thereof, wherein the cooling passage is arranged without being connected to the groove. 7. An airtight casing enclosing a cooling gas,
A stator assembly including a stator core in which a plurality of radial cooling passages arranged in the axial direction are provided, which is arranged in the casing, and a stator core, which rotates in an inner peripheral portion of the stator core through a gas gap. A rotating electric machine having a rotatably supported rotor and a gas cooler arranged in the casing, and an axial groove for accommodating a conductor is provided on the inner diameter side of the stator core. In the rotary electric machine, the radial cooling passage does not interfere with the axial groove on the inner diameter side. 8. A rotary electric machine in which a stator assembly including a stator core is arranged in an airtight casing containing cooling gas, wherein a plurality of the stator cores are provided in the axial direction, and each of the cooling gas contains the cooling gas. A rotating electrical machine comprising: a cooling passage having an opening of a predetermined size, which is circulated in a radial direction.