JP2005143268A - Rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary electric machine in which a size reduction and a high performance are realized by improving a cooling method. <P>SOLUTION: In the rotary electric machine, assuring of a magnetic path by the deflection of a magnetic flux line 35 and enlarging of a region 36 which can be cooled, are realized by forming a stator core 33 of a dust core material and adding a collar-like additional region 33a to this stator core 33. The reason why such a constitution is formed is because since a loss heat is generated in response to a magnetic flux in the stator core 33 and simultaneously the heat is added as the current loss of the stator coil 34 itself at the place where the magnetic flux in the stator core 33 is generated around a stator coil 34 from the stator to the magnet of a rotor, it is desired to set a refrigerant channel 36 in the region which surrounds the magnetic flux in the stator core 33. In other words, the stator core 33 is suitable to have the refrigerant channel 36 in the interior or the front surface of the stator core of the region which is not interfered with the dense part the magnetic flux line 35 generated with the stator coil 34, and passing through the interior of the stator core 33. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a rotating electrical machine, and more particularly to an improvement of a rotating electrical machine characterized in that a stator is directly cooled by a liquid refrigerant.

  In order to reduce the size and increase the performance of a rotating electrical machine, technology that can cope with an increase in thermal load is required. In particular, as electric vehicles and hybrid vehicles are being put into practical use, further downsizing and higher performance of rotating electric machines are required.

  Heat generated by the rotating electrical machine is generated in the magnetic flux generation region of the constituent elements such as the iron core and coil (or magnet) in the stator and the magnet (or iron core and coil) in the rotor. The iron core around which the coil is wound in the stator (or the rotor) generates a large amount of heat, and its rotation speed dependency is larger than that of the coil. Furthermore, since coil heating is also applied to the iron core, the iron core in the vicinity of the coil is highly required to be cooled.

For example, the heat generation density of a rotating electrical machine is (1) 0.1 W / cm ³ or less for a general-purpose motor, (2) increases from 0.2 to 0.6 W / cm ³ from a small and high load motor, (3 ) Motors with high rotation speeds also change to 1-10 W / cm ³ . For the general-purpose motor shown in (1), the air-cooling method currently in practical use is appropriate, but in order to reach (2) and (3), a cooling method using liquid is unavoidable.

  Conventionally, several techniques have been disclosed for stator cooling by a liquid refrigerant of a rotating electrical machine represented by a motor. These motors are intended for coaxial cylindrical radial motors, and a refrigerant flow path is provided in the stator. In the motor described in Patent Document 1 below, the refrigerant flow path along the axis is set in the yoke portion of the stator. However, it is assumed that a laminated steel plate is used for the iron core in order to ensure effective magnetic flux. In such a structure using a laminated steel plate, it is difficult to set an arbitrary flow path, and only a flow path parallel to the axis can be set as a refrigerant flow path. In order to construct a closed cooling circuit including a pump and a heat exchanger, a joint for joining a large number of laminated steel plates that form a refrigerant flow path is required. It is difficult to adopt a screw structure. Moreover, in the structure using laminated steel plates, the occurrence of refrigerant leakage is unavoidable and is not practical. In order to improve the leakage of the refrigerant, it is possible to insert a separate channel pipe in the refrigerant channel of the stator. In this case, however, there is a contact thermal resistance between the inner surface of the refrigerant channel and the outer surface of the channel tube. Therefore, the effect of direct liquid cooling is greatly reduced. Therefore, the direct cooling of the stator by the liquid refrigerant in the prior art such as the invention described in the following Patent Document 1 is less feasible.

  Further, Patent Document 2 below discloses an invention in which a groove is formed on the outer peripheral surface of a yoke portion of a radial motor, and a liquid refrigerant channel is formed between the outer casing and the outer casing. In the case of the present invention, the refrigerant flow path is circumferential, and a complicated mechanism is required for the liquid seal installed between the case and the case. Furthermore, in order to avoid interference with the magnetic flux, it is necessary to set a flow path in a region away from the coil, and the effect of direct cooling is reduced (as another similar technique, for example, Patent Document 3 below) reference).

JP 2002-165410 A Japanese Patent Laid-Open No. 08-322170 JP 05-236705 A

  With the conventional technologies listed in the background art, it is difficult to achieve further downsizing and higher performance of rotating electrical machines that are required in current electric vehicles and hybrid vehicles.

  In particular, in an axial motor used in an electric vehicle or a hybrid vehicle, the iron core in the stator is assumed to generate magnetic flux in the axial direction, so that the difficulty of miniaturization and high performance becomes remarkable. If the steel sheet used in a conventional radial type motor is to be used in an axial type motor, the iron core must be shaped in the radial direction of the steel sheet, that is, in the form of a stack of thin cylindrical plates. It is. It is practically difficult to make an iron core of an axial motor by laminating steel plates in close contact with each other while applying electrical insulation. In addition, there is a problem that an arbitrary cooling channel cannot be set for direct cooling to the laminated steel sheet. Therefore, the present situation is that an axial type motor using a laminated steel plate that inevitably has a large amount of heat loss and requires strong cooling has not been realized.

  The present invention has been made in view of the above problems, and provides a new iron core cooling structure for reducing the size and performance of a rotating electrical machine.

  A rotating electrical machine according to the present invention is a stationary electric machine in which a rotor that is a field magnetic flux generation source and a plurality of stator coils that generate a rotating magnetic field that rotates the rotor are wound around a plurality of sets of stator cores. The stator core includes a plurality of teeth around which the stator coil is wound, and a stator coil formed in a bowl shape in a radial direction at least on one end side of the teeth. The teeth and the back yoke are integrally formed of a dust core material, and are generated by the stator coil and do not interfere with the dense portions of the magnetic flux lines passing through the stator core. A refrigerant flow path is provided in or on the surface of the stator iron core.

  Another rotating electrical machine according to the present invention includes a rotor that is a field magnetic flux generation source and a plurality of stator coils that generate a rotating magnetic field that rotates the rotor wound around a plurality of sets of stator cores. In the axial type rotating electrical machine including the stator, the stator iron core is formed in a bowl shape in a radial direction at least on one end side of the teeth, and a plurality of teeth around which the stator coil is wound. A back yoke that supports the coil, and at least the back yoke is formed of a powder magnetic core material and is generated by the stator coil and does not interfere with a dense portion of magnetic flux lines that pass through the stator core A refrigerant flow path is provided in or on the surface of the stator iron core.

  In the rotating electrical machine according to the present invention, the stator core is an aggregate of divided cores around which stator coils are wound, and the refrigerant flow path is formed for each of the divided cores. .

  In the rotating electrical machine according to the present invention, the stator iron core is integrally formed, and the refrigerant flow path is formed over the entire stator core integrally formed.

  Furthermore, in the rotating electrical machine according to the present invention, the inlet / outlet portion of the refrigerant flow path is provided on a surface other than the coil installation surface of the stator core or a surface other than the rotor side of the stator core. It is characterized by.

  Furthermore, in the rotating electrical machine according to the present invention, a corrosion-resistant film is formed on the wall surface of the refrigerant flow path.

  Furthermore, in the rotating electrical machine according to the present invention, the refrigerant flow path is formed in a fin shape.

  Another rotating electrical machine according to the present invention includes a rotor that is a field flux generation source and a plurality of stator coils that generate a rotating magnetic field that rotates the rotor wound around a plurality of sets of stator cores. The rotor includes a stator core around which the stator coil is wound, and has an open end on the stator coil installation side of the stator core. A case portion having an opening end portion of the case portion, and a cover portion forming a housing case for sealing the stator core in cooperation with the case portion, the housing case and the fixing A space formed between the stator core around which the child coil is wound is used as a refrigerant flow path for liquid refrigerant.

  Further, in another rotating electrical machine according to the present invention, the cover portion of the housing case is formed in cooperation with a stator core.

  Furthermore, in another rotating electrical machine according to the present invention, the case portion and the cover portion forming the housing case are formed of a nonmagnetic insulating material.

  Still further, in another rotating electrical machine according to the present invention, the surface of the stator coil is wrapped with insulating paper, and the periphery thereof is removed by being immersed in a liquid refrigerant introduced into the refrigerant flow path. It is characterized by.

  Furthermore, in another rotating electrical machine according to the present invention, the case portion includes an inflow guide for introducing the liquid refrigerant into the refrigerant flow path, and an outflow guide for deriving the liquid refrigerant from the refrigerant flow path. .

  In another rotating electrical machine according to the present invention, the liquid refrigerant is circulated through a refrigerant flow path by a fluid pump capable of controlling a flow rate.

  Furthermore, another rotating electrical machine according to the present invention is characterized by further comprising a cooling means for cooling the liquid refrigerant.

  Another rotating electrical machine according to the present invention comprises a rotor that is a field flux generation source and a plurality of stator coils that generate a rotating magnetic field that rotates the rotor wound around a plurality of sets of stator cores. The stator core includes a plurality of teeth around which a stator coil is wound, and a hook-like shape in a radial direction at least on one end side of the teeth. A back yoke that supports the stator coil, and the teeth and the back yoke are integrally formed of a dust core material, and further, a dense portion of magnetic flux lines generated by the stator coil and passing through the stator core A first refrigerant flow path is provided inside or on the surface of the stator core, which is a region that does not interfere, and the rotor accommodates the stator core around which the stator coil is wound, and the stator core of the stator core A case portion having an open end on the installation side, and a cover portion that is installed at the open end of the case portion and forms a housing case for sealing the stator core in cooperation with the case portion; A space formed between the housing case and a stator core around which the stator coil is wound is used as a second refrigerant flow path.

  Still another rotating electrical machine according to the present invention comprises a rotor that is a field magnetic flux generation source and a plurality of stator coils that generate a rotating magnetic field that rotates the rotor wound around a plurality of sets of stator cores. The stator iron core is formed in a plurality of teeth around which the stator coil is wound and a bowl shape in a radial direction at least on one end side of the teeth. A back yoke supporting the stator coil, and at least the back yoke is formed of a powder magnetic core material, and further, a dense portion of magnetic flux lines generated by the stator coil and passing through the stator core; A first refrigerant flow path is provided inside or on the surface of the stator core, which is a non-interfering area, and the rotor houses the stator core around which the stator coil is wound, and the stator core stator. A case portion having an open end on the side where the coil is installed, and a cover portion which is installed at the open end of the case portion and forms a housing case for sealing the stator core in cooperation with the case portion. And a space formed between the housing case and a stator core around which the stator coil is wound is defined as a second refrigerant flow path.

  According to the present invention, the “stator core only” or “stator core and stator coil” having a high heat generation amount and high heat density without affecting the performance characteristics of the rotating electric machine and having a high cooling effect as a refrigerant. Can be cooled directly. By increasing the cooling effect in this way, it is possible to provide a rotating electrical machine that is reduced in size and performance.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Preferred embodiments for carrying out the invention will be described with reference to the drawings. In the present embodiment, a case where the present invention is applied to an axial motor will be described as an example. However, the technical scope of the present invention is not limited to the scope described in the following embodiment, and various modifications or improvements can be added to the following embodiment. It is apparent from the description of the scope of claims that embodiments with such changes or improvements can be included in the technical scope of the present invention.

Embodiment 1
First, the structure of an axial motor to which this embodiment is applied will be described. FIG. 1 is a schematic cross-sectional view of an axial type motor. 2 shows the rotor of the axial type motor exemplified in FIG. 1, and FIG. 3 shows the stator of the axial type motor exemplified in FIG.

  The axial type motor includes a disk-shaped rotor 10 having a plurality of permanent magnets 11 and stators 12 arranged on both sides thereof. The rotor 10 becomes a field magnetic flux generation source by the permanent magnet 11, and can be rotated in accordance with a rotating magnetic field generated from the stator 12. On the other hand, the stator 12 has a plurality of poles around which the stator coil 14 is wound around the teeth 13a of the stator core 13. In the case of the axial type motor illustrated in FIG. The stator 12 is arranged coaxially. In addition, as shown in FIG. 3B, the stator 12 needs to have a large number of stator coils 14 and stator cores 13 for forming magnetic poles arranged concentrically. Therefore, the stator core 13 includes a plurality of teeth 13a, and one end side of the teeth 13a is disposed on the ring-shaped back yoke 13b so that the plurality of stator coils 14 can be fitted therein. . That is, the stator 12 is configured by winding a plurality of pairs of stator coils 14 that generate a rotating magnetic field for rotating the rotor 10 around a plurality of sets of stator cores 13. The stator core 13 may be configured as a single stator core 13 as illustrated in FIG. 4 as a whole, or the core 15 divided for each pole as illustrated in FIG. It is good also as comprising and forming the stator core 13 as an aggregate | assembly of this iron core 15. FIG.

  Here, a stator core formed of a conventional laminated steel plate will be described. FIG. 6 is a view showing the structure of a conventional stator core composed of laminated steel sheets. FIG. 7 shows the direction of the magnetic flux lines passing through the stator core composed of laminated steel plates and the area where the refrigerant flow path can be installed by avoiding the magnetic flux lines.

  In the conventional stator core 23 described above, since the laminated steel plates are laminated in the radial direction, the magnetic flux lines 25 that are generated in the central axis direction of the coil 24 and pass through the stator core 23 are bypassed in the radial direction. It was difficult. This is because the radial magnetic flux path must pass through the laminated surface, and the magnetic resistance increases. This means that the installation area 26 of the refrigerant flow path provided in the area avoiding the magnetic flux path has to be reduced due to the restriction of the passage direction of the magnetic flux lines 25 of the laminated steel iron stator core 23. It is shown that. That is, in the stator core 23 made of laminated steel plate, the magnetic flux line is deflected by expanding the magnetic path by setting the additional region 23a of the laminated steel plate as shown by the hatched portion in FIG. This means that it is impossible to take measures to increase the number of people.

  On the other hand, FIG. 8 shows the direction of the magnetic flux lines passing through the stator core and the refrigerant flow path that can be provided by avoiding the magnetic flux lines when the present invention is applied to the stator core of an axial motor. Indicates the area. A feature of the present invention resides in that a stator core that has been conventionally constituted by laminated steel sheets is constituted by a dust core material.

  Here, the powder magnetic core material is an object that is pressure-molded after an electrically insulating film is applied to a fine iron powder material, and is desirable as a block like a bulk material because the insulating materials are pressure-bonded to each other. A product in the form of can be obtained. Since the molded product of the dust core material is an aggregate of fine iron powder as a whole, an arbitrary three-dimensional shape can be formed alone. When viewed macroscopically, there is no electrical or thermal anisotropy, so there is no limitation on the direction of the internal magnetic flux lines, and it has the great feature of enabling three-dimensional deflection of the magnetic flux lines.

  By forming the stator core 33 with the dust core material having such characteristics, the magnetic flux lines 35 are allowed to have three-dimensionality. Therefore, the magnetic flux lines 35 extending from the core are not only in the circumferential direction but also in the radial direction. Will be added. Furthermore, it is possible to increase the magnetic path by adding the additional region 33a provided in a bowl shape in the radial direction, which is meaningless in the laminated steel sheet. Accordingly, since all the magnetic flux lines 35 are distributed to all the side surfaces of the iron core, the coolable region 36 on the back surface of the iron core is expanded. 8 (b) and 8 (c), the refrigerant flow path installable region 36 is shown by comparing the conventional case with the case of the present embodiment, but the refrigerant flow path placement in the present embodiment is shown. It is shown that the possible region 36 extends in the radial direction as well as the circumferential direction when viewed from the back, and can be set deep inside the iron core.

  As described above, in the present embodiment, the stator core 33 is formed of a dust core material, and the hook-shaped additional region 33 a is added to the stator core 33, thereby securing a magnetic path by deflection of the magnetic flux lines 35. The enlargement of the coolable region 36 can be realized. Note that the magnetic flux in the stator core 33 is generated from the stator to the rotor magnet around the stator coil 34, and heat loss is generated in the stator core 33 according to the magnetic flux and at the same time the stator coil 34 itself. Since heat generation as a current loss is also applied, it is desirable to set the refrigerant flow path 36 in a region surrounding the magnetic flux in the stator core 33. That is, it is necessary to provide the refrigerant flow path 36 inside or on the surface of the stator core, which is an area that is generated by the stator coil 34 and does not interfere with the dense portion of the magnetic flux lines 35 that pass through the stator core 33.

  Next, a specific configuration of the refrigerant flow path will be described. FIG. 9 is a side view of the flow path setting region 36 of the stator core 33 shown in FIG. FIG. 9 is a cross-sectional view showing the case viewed from the radial direction. In FIG. 9, a single pole is illustrated, and a refrigerant flow path 36 a that secures a necessary heat removal amount is installed inside the stator core 33. Compared to the conventional stator core 23, a very wide area can be used as the refrigerant flow path 36a. In addition, in this embodiment demonstrated below, the refrigerant | coolant entrance / exit part 37 is made into the surface opposite to the coil 34 installation side, It is characterized by the above-mentioned. This is because a single pole assembly can be taken out between the poles, but convenience is higher on the opposite side of the coil. However, the refrigerant inlet / outlet portion 37 of the refrigerant flow path can be provided on a surface other than the coil installation surface of the stator core or a surface other than the rotor side of the stator core.

  FIG. 10 is an example in which the refrigerant flow path 36a is set in a wide area on the back surface, and can be realized by application of a casting technique using a feature of pressure molding such as lost wax. The refrigerant inlet / outlet portion 37 is taken out from the back to the case side having a degree of freedom so that it has a good sealing property with the powder magnetic core material and can have a practical flow path configuration without leakage.

  In FIG. 11, in order to correspond to the heat generation point of the stator coil 34, a refrigerant flow path 36 a is set inside the iron core and in the vicinity of the coil 34. The connection of the refrigerant flow path 36a and the like are the same as in FIG.

  FIG. 12 is a diagram illustrating a case where the surface of the iron core is a refrigerant flow path 26a in a stator iron core using a conventional laminated steel plate. In the conventional stator core illustrated in FIG. 12, the coolant flow path 26a is formed by machining such as cutting, but the same method can be applied to the present invention. FIG. 13 shows the embodiment, in which a coolant channel 36a is formed by machining in a region corresponding to the channel settable region 36 shown in FIG. From the three-dimensional nature of the magnetic flux, the refrigerant flow path 36a can be set deep from the wall surface. Moreover, it is also possible to increase a heat-transfer area by taking a fin shape and to increase a cooling effect. The fin-like refrigerant flow path 36a illustrated in FIG. 13 is characterized in that the refrigerant flow path can be easily realized as compared with the iron core internal flow path. Since a refrigerant flow path is formed between the motor cases 28 and 38, it is necessary to add a liquid refrigerant leakage prevention mechanism such as an O-ring. Therefore, the realization is easy.

  FIG. 14 shows an example of forming a refrigerant flow path on the surface of the iron core utilizing the characteristics of the dust core material. The flow path length (area) corresponding to the heat load is set on the coil opposite surface. It is preferable that the refrigerant inlet / outlet portion 37 is also set on the opposite side of the coil.

  The present invention can be applied regardless of how the stator coil is wound. That is, the refrigerant flow path 36a can be set regardless of the difference between concentrated winding and distributed winding as exemplified in FIG. Further, the present invention can be applied to either a single pole or a multipole assembly regardless of the pole splitting method of the iron core.

  As described above, the refrigerant flow path configuration when the iron core is formed of a dust core material is any three-dimensionally possible magnetic flux direction in the iron core. The flow path can be formed there by expanding the iron core part. (2) By changing the direction of the magnetic flux to another direction even in the region where the flow path is difficult to form in the conventional laminated steel plate, the influence of the magnetic flux is strong. The refrigerant flow path can be set for areas where the influence of magnetic flux is weak, and (3) the iron core is expanded to an area where the influence of magnetic flux is small, and the stator yoke thickness is reduced by guiding the magnetic flux there. And the effect which is not in the prior art that a motor can be reduced in size can be acquired.

  In the present embodiment, the case where the stator core 13 including the teeth 13a and the back yoke 13b is integrally formed of a dust core material has been described as an example. However, the present invention is not limited to such an embodiment. For example, the stator core 13 may be configured by using the teeth 13a as an electromagnetic steel plate such as a silicon steel plate and the back yoke 13b as a dust core material. Is preferred. In this case, the magnetic flux lines 35 coming out of the iron core have the same directionality in the teeth 13a portion and are allowed to have three-dimensionality in the back yoke 13b portion. Thus, the coolable region 36 on the back surface of the iron core is expanded.

  In addition, according to the present embodiment, a sufficient magnetic path of the magnetic flux lines 35 can be secured, so that not only the coolable region 36 on the back surface of the iron core is enlarged, but also the stator core 13 is reduced in size and weight. It is also possible. Therefore, according to the present invention, it is possible to reduce the size and increase the performance of the rotating electrical machine without affecting the performance characteristics of the rotating electrical machine.

Any liquid refrigerant introduced into the refrigerant flow path may be used as long as it can be a cooling working fluid such as oil, water, freon, fluorinate, and CO ₂ . Furthermore, it is preferable to form an organic or inorganic corrosion-resistant film on the surface of the refrigerant flow path in order to extend the life of the dust core material constituting the refrigerant flow path.

  FIG. 16 compares the effect of direct cooling of the iron core when oil is used. When the stator is not cooled at a motor rotational speed of 3,000 rpm (the motor is in an ambient atmosphere), the temperature rise of the member is remarkable and far exceeds its heat resistance limit. The conventional technology for cooling the motor case with water still has a cooling effect but still exceeds the heat resistance limit. This is due to the contact thermal resistance between the iron core and the motor case. Although it is expected to have a large improvement effect, its feasibility is poor. On the other hand, it can be seen that the heat resistance limit can be easily overcome in the case of direct oil cooling of the iron core using the present invention.

Embodiment 2
In the first embodiment described above, a rotating electrical machine has been described in which a coolant channel is formed in the stator core, and the stator core is directly cooled by the liquid refrigerant introduced into the coolant channel. On the other hand, this embodiment demonstrates the rotary electric machine which can cool not only a stator core but a stator coil directly with a liquid refrigerant.

  First, the structure of an axial motor to which this embodiment is applied will be described. FIG. 17 is a schematic cross-sectional view of a conventional axial type motor.

  A conventional axial motor is composed of a disk-shaped rotor 110 having a plurality of permanent magnets and stators 112 arranged on both sides thereof. The rotor 110 becomes a field magnetic flux generation source by a permanent magnet, and can be rotated in accordance with a rotating magnetic field generated from the stator 112. On the other hand, the stator 112 has a structure in which a plurality of poles around which a stator coil 114 is wound are provided on a tooth portion of the stator core 113. That is, the stator 112 is configured by winding a plurality of phases of stator coils 114 that generate a rotating magnetic field for rotating the rotor 110 around a plurality of sets of stator cores 113. In the case of the axial type motor illustrated in FIG. 17, the two stators 112 are arranged on the same shaft 111. In addition, a predetermined space gap 115 exists between the rotor 110 and the stator 112, and this space gap 115 needs to be set to an appropriate value for driving the motor. Further, the rotor 110 and the stator 112 are housed in a motor case 116 to constitute an axial type motor.

  Next, the axial type motor according to the present embodiment will be described with reference to the drawings. FIG. 18 is a schematic cross-sectional view of the axial type motor according to the present embodiment. What is characteristic of this embodiment is that the stator 112 is sealed with a housing case called a motor case 120, and a space formed between the motor case 120 and the stator 112 is defined as a refrigerant flow path 123 for liquid refrigerant. It is that. Needless to say, the spatial gap 115 existing between the rotor 110 and the stator 112 is maintained at a predetermined value in this embodiment in order to maintain the performance of the axial motor.

  The motor case 120 is formed by two members, a case part 122 and a cover part 121. The case portion 122 can accommodate the stator core 113 around which the stator coil 114 is wound, and has a shape having an open end 122 a on the stator coil 114 installation side of the stator core 113. On the other hand, the cover part 121 is installed at the opening end part 122 a of the case part 122, thereby forming a motor case 120 which is a housing case for sealing the stator 112 in cooperation with the case part 122. become.

  Then, in order to explain the axial type motor according to the present embodiment more clearly, it will be described with reference to FIG. FIG. 19 is a perspective view of a main part for explaining the structure of the axial type motor according to the present embodiment. FIG. 19A shows a state in which the cover 121 is attached, and FIG. Indicates a state in which the cover 121 is removed.

  First, the stator core 113 around which the stator coil 114 is wound is stored in the case portion 122 leaving a predetermined space (see FIG. 19B). Next, the stator 120 is hermetically sealed by installing the cover 121 on the open end 122a of the case 122 (see FIG. 19A). In the axial type motor illustrated in FIG. 19, the cover 121 has an opening 121 a, and the opening 121 a is formed so that the teeth 113 a of the stator core 113 are fitted. Accordingly, in the embodiment shown in FIG. 19, the case portion 122, the cover portion 121, and the stator core 113 cooperate to form a motor case 120 that is a housing case. A predetermined space exists between the motor case 120 and the stator 112 formed in this way, and this space is used as the refrigerant flow path 123 of the liquid refrigerant.

  The case portion 122 and the cover portion 121 that form the motor case 120 are preferably formed of a nonmagnetic insulating material. Further, since the stator coil 114 is in direct contact with the cooling medium, the surface is wrapped with insulating paper. Then, the periphery of the stator coil 114 is immersed in the liquid refrigerant introduced into the refrigerant flow path, and heat is removed.

  FIG. 20 is a view showing a state in which oil as a cooling medium is introduced into the axial type motor according to the present embodiment formed as described above. The hatched portion in the figure indicates the oil 130 introduced into the refrigerant flow path 123. As is clear from FIG. 20, since the stator core 113, the stator coil 114, and the motor case 120 all come into contact with the oil 130, a very large cooling effect is exhibited according to the present invention. .

  Next, a method for introducing the liquid refrigerant (oil 130) into the refrigerant flow path 123 will be described with reference to FIGS. FIG. 21 is a view for explaining the liquid refrigerant introducing means provided in the case portion 122, FIG. 22 is a view showing the flow direction of the liquid refrigerant, and FIG. 23 is a view for explaining the flow control mechanism of the liquid refrigerant. FIG.

  As shown in FIGS. 21 and 22, on the bottom surface of the case portion 122, an inflow guide 131 for introducing the liquid refrigerant into the refrigerant channel 123 and an outflow guide 132 for deriving the liquid refrigerant from the refrigerant channel 123. Is provided. As shown in FIG. 21B, the inflow guide 131 and the outflow guide 132 are preferably installed at positions along the inner peripheral surface and the outer peripheral surface of the stator core 113, respectively. By making it smooth, the cooling effect can be further enhanced. In addition, since the inflow guide 131 and the outflow guide 132 can exhibit the same effect even if installed on the opposite side, the present embodiment is not limited to the flow direction shown in FIG. . A pump 133 for circulating the liquid refrigerant is installed in the pipe connecting the inflow guide 131 and the outflow guide 132 (see FIG. 23). The pump 133 can control the flow rate of the liquid refrigerant. By performing the flow rate control, the circulation flow rate of the liquid refrigerant can be managed, and optimal temperature management of the axial motor can be performed.

  As a means for cooling the liquid refrigerant that has absorbed heat from the stator core 113, the stator coil 114, and the motor case 120, for example, as shown in FIG. It is possible to remove the heat of the oil 130 as the cooling medium. Further, the heat of the oil 130 may be removed using an oil cooler.

  Note that the structures of the case portion 122 and the cover portion 121 constituting the motor case 120 are not limited to the shapes described above, and various modifications as shown in, for example, (a) to (d) of FIG. An example can be applied. That is, it is only necessary that the stator 112 can be hermetically sealed and a space that can serve as the refrigerant flow path 123 is provided between the stator 112 and the stator 112.

  In order to confirm the effect of the second embodiment described above, the heat conduction analysis of the stator core, the stator coil, and the motor case was performed, and the internal cooling effect was examined. 26, 27, and 28 are diagrams showing the results.

  In this heat conduction analysis, the periodicity of the phenomenon and the heat generation distribution were considered, and 1/12 of the axial type motor was the analysis target. The analysis is performed with the insulating paper 141 wound around the stator coil 140. FIG. 26 shows boundary conditions for heat conduction analysis. FIG. 27 shows the results for (a) when cooled according to the present invention, (b) when a flow path is installed in the iron core 142 and cooled, and (c) when the motor case 143 is cooled.

  As analysis conditions, (c) when the motor case 143 was cooled, water cooling was performed, and the entire case was cooled. It has been found that when the motor case 143 is cooled, the coil temperature does not decrease due to the influence of the contact thermal resistance between the insulating paper 141 wound around the stator coil 140 and the stator core 142.

  In addition, (b) the case where the iron core portion 142 is cooled and (a) the cooling according to the present invention are oil-cooled, and the heat transfer coefficient is the same. In the case of (b) direct cooling of the stator core 142, unlike the case of (c) motor case 143 cooling, it was found that the stator core 142 is effectively cooled and has a certain effect. However, the coil temperature did not decrease due to the influence of the contact thermal resistance between the insulating paper 141 wound around the stator coil 140 and the stator core 142.

  On the other hand, (a) in the case of cooling according to the present invention, oil is immersed between the insulating paper 141 wound around the stator coil 142 and the stator core 142, so that the influence of the contact thermal resistance is reduced, and the temperature difference in the entire motor. It was confirmed that almost disappeared. Moreover, since the stator coil 140 and the stator core 142 were directly cooled, it was confirmed that the cooling effect was great.

  Next, the temperature results in the radial direction are shown in FIG. As can be seen from the result of FIG. 28B, when the cooling is performed according to the present invention, there is almost no temperature difference between the stator coil 140 and the stator core 142. It was also confirmed that the temperature difference from the motor case temperature was small compared to other cooling. From the above analysis results, the cooling effect according to the present invention was clarified.

Embodiment 3
By combining the two embodiments 1 and 2 described above, it is possible to realize a rotating electrical machine that exhibits a further cooling effect. These combinations can be arbitrarily selected depending on the required performance of the rotating electrical machine to be obtained. By adopting an optimal cooling method, it is possible to realize a rotating electrical machine that exhibits the maximum capability.

It is a cross-sectional schematic diagram of an axial type motor. It is a figure which shows the rotor of the axial type motor illustrated by FIG. It is a figure which shows the stator of the axial type motor illustrated by FIG. It is a figure which shows the stator core of an axial type motor in case the whole pole is comprised as a single stator core. It is a figure which illustrates one of the division | segmentation iron cores in case the stator iron core of an axial type motor is the aggregate | assembly of the iron core divided | segmented for every pole. It is a figure which shows the structure of the conventional stator iron core comprised with the laminated steel plate. It is a figure which shows the installation possible area | region of the refrigerant | coolant flow path which can be provided by avoiding a magnetic flux line direction and the direction of the magnetic flux line which passes through the stator iron core comprised with the laminated steel plate. It is a figure which shows the installation possible area | region of the refrigerant | coolant flow path which can be provided by avoiding a direction of the magnetic flux line which passes a stator core at the time of applying this invention to the stator iron core of an axial type motor, and a magnetic flux line. . It is the figure which looked at the flow-path setting possible area | region of the stator core shown in FIG. 8 from the side surface. It is a figure which shows the example of a setting of the refrigerant flow path in this invention. It is a figure which shows the example of a setting of the refrigerant flow path in this invention. It is a figure which illustrates the case where the iron core surface is used as a refrigerant channel in the conventional stator iron core using laminated steel plates. It is a figure which illustrates the case where the conventional refrigerant flow path shown in FIG. 12 is applied to this invention. It is a figure which shows the example of refrigerant | coolant flow path formation to the iron core surface using the characteristic of a powder magnetic core material. It is a figure for demonstrating that this invention is applicable irrespective of how to wind a stator coil. It is the figure which compared the effect of iron core direct cooling about the case where oil is used. It is a figure which shows the schematic cross section of the conventional axial type motor. It is a figure which shows the schematic cross section of the axial type motor which concerns on this invention. It is a principal part perspective view for demonstrating the structure of the axial type motor which concerns on this invention, (a) has shown the state in which the case part was mounted | worn, (b) has shown the state which removed the case part Yes. It is a figure which shows the state which introduced the oil as a cooling medium to the axial type motor which concerns on this invention. It is a figure for demonstrating the introduction means of the liquid refrigerant with which the case part of the axial type motor which concerns on this invention is provided. It is a figure which shows the flow direction of the liquid refrigerant in the axial type motor which concerns on this invention. It is a figure for demonstrating the flow control mechanism of the liquid refrigerant in the axial type motor which concerns on this invention. It is a figure which illustrates the cooling means of the liquid refrigerant in the axial type motor which concerns on this invention. It is a figure which shows the various modifications of the motor case in the axial type motor which concerns on this invention. It is a figure which shows the boundary conditions of heat conduction analysis. It is a figure which shows the analysis result of a heat conduction analysis. It is a figure which shows the temperature result of the radial direction of the axial type motor in a heat conduction analysis.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Rotor, 11 Permanent magnet, 12 Stator, 13, 23, 33 Stator iron core, 13a Teeth, 13b Back yoke, 14, 24, 34 Stator coil, 15 (Split) iron core, 23a, 33a Additional area, 25 , 35 Magnetic flux lines, 26, 36 Refrigerant flow path installable area, 26a, 36a Refrigerant flow path, 28, 38 Motor case, 37 Refrigerant inlet / outlet part, 110 rotor, 111 shaft, 112 stator, 113, 142 Stator core , 113a Teeth section, 114, 140 Stator coil, 115 Spatial gap, 116, 120, 143 Motor case, 121 Cover section, 121a opening section, 122 case section, 122a Open end section, 123 Refrigerant flow path, 130 Oil, 131 Inflow guide, 132 Outflow guide, 133 Pump, 134 Fin, 141 Insulating paper.

Claims (16)

A rotor which is a field magnetic flux generation source;
A stator configured by winding a plurality of sets of stator coils around a stator core to generate a rotating magnetic field for rotating the rotor;
In the axial type rotating electrical machine including
The stator core is
A plurality of teeth around which a stator coil is wound;
A back yoke that is formed in a bowl shape in a radial direction at least on one end side of the teeth and supports the stator coil;
And the teeth and the back yoke are integrally formed of a powder magnetic core material,
A rotating electrical machine comprising a refrigerant flow path in or on a stator core, which is an area that is generated by a stator coil and does not interfere with a dense portion of magnetic flux lines that pass through the stator core. A rotor which is a field magnetic flux generation source;
A stator configured by winding a plurality of sets of stator coils around a stator core to generate a rotating magnetic field for rotating the rotor;
In the axial type rotating electrical machine including
The stator core is
A plurality of teeth around which a stator coil is wound;
A back yoke that is formed in a bowl shape in a radial direction at least on one end side of the teeth and supports the stator coil;
And at least the back yoke is formed of a powder magnetic core material, and
A rotating electrical machine comprising a refrigerant flow path in or on a stator core, which is an area that is generated by a stator coil and does not interfere with a dense portion of magnetic flux lines that pass through the stator core. In the rotating electrical machine according to claim 1 or 2,
The stator iron core is an assembly of split iron cores around which stator coils are wound, and the refrigerant flow path is formed for each of the split iron cores. In the rotating electrical machine according to claim 1 or 2,
The rotating electric machine according to claim 1, wherein the stator core is integrally formed, and the refrigerant flow path is formed over the integrally formed stator core. In the rotating electrical machine according to any one of claims 1 to 4,
The rotating electrical machine characterized in that the inlet / outlet portion of the refrigerant flow path is provided on a surface other than the coil installation surface of the stator core or a surface other than the rotor side of the stator core. In the rotary electric machine according to any one of claims 1 to 5,
A rotating electrical machine, wherein a corrosion-resistant film is formed on a wall surface of the refrigerant flow path. In the rotary electric machine according to any one of claims 1 to 6,
The rotating electrical machine, wherein the refrigerant flow path is formed in a fin shape. A rotor which is a field magnetic flux generation source;
A stator configured by winding a plurality of sets of stator coils around a stator core to generate a rotating magnetic field for rotating the rotor;
In the axial type rotating electrical machine including
The rotor is
A case portion having an open end on the stator coil installation side of the stator core, while storing the stator core around which the stator coil is wound,
A cover part that is installed at an opening end of the case part and forms a housing case for sealing the stator core in cooperation with the case part;
With
A rotating electrical machine characterized in that a space formed between the housing case and a stator core around which the stator coil is wound serves as a refrigerant flow path for liquid refrigerant. The rotating electrical machine according to claim 8,
The rotating electric machine according to claim 1, wherein the cover portion of the housing case is formed in cooperation with a stator core. In the rotating electrical machine according to claim 8 or 9,
A rotating electric machine characterized in that a case portion and a cover portion forming the housing case are formed of a nonmagnetic insulating material. The rotating electrical machine according to any one of claims 8 to 10,
The rotating electric machine is characterized in that the surface of the stator coil is wrapped with insulating paper, and the periphery thereof is removed by being immersed in a liquid refrigerant introduced into the refrigerant flow path. The rotating electrical machine according to any one of claims 8 to 11,
The case portion is
An inflow guide for introducing liquid refrigerant into the refrigerant flow path;
An outflow guide for leading the liquid refrigerant from the refrigerant flow path;
A rotating electric machine comprising: The rotating electrical machine according to any one of claims 8 to 12,
The rotary electric machine is characterized in that the liquid refrigerant circulates in the refrigerant flow path by a fluid pump capable of controlling the flow rate. The rotating electrical machine according to any one of claims 8 to 13,
A rotating electrical machine comprising cooling means for cooling the liquid refrigerant. A rotor which is a field magnetic flux generation source;
A stator configured by winding a plurality of sets of stator coils around a stator core to generate a rotating magnetic field for rotating the rotor;
In the axial type rotating electrical machine including
The stator core is
A plurality of teeth around which a stator coil is wound;
A back yoke that is formed in a bowl shape in a radial direction at least on one end side of the teeth and supports the stator coil;
And the teeth and the back yoke are integrally formed of a powder magnetic core material,
A first refrigerant flow path is provided inside or on the surface of the stator core that is generated by the stator coil and does not interfere with the dense portion of the magnetic flux lines passing through the stator core,
The rotor is
A case portion having an open end on the stator coil installation side of the stator core, while storing the stator core around which the stator coil is wound,
A cover part that is installed at an opening end of the case part and forms a housing case for sealing the stator core in cooperation with the case part;
With
A rotary electric machine characterized in that a space formed between the housing case and a stator core around which the stator coil is wound is a second refrigerant flow path. A rotor which is a field magnetic flux generation source;
A stator configured by winding a plurality of sets of stator coils around a stator core to generate a rotating magnetic field for rotating the rotor;
In the axial type rotating electrical machine including
The stator core is
A plurality of teeth around which a stator coil is wound;
A back yoke that is formed in a bowl shape in a radial direction at least on one end side of the teeth and supports the stator coil;
And at least the back yoke is formed of a powder magnetic core material, and
A first refrigerant flow path is provided inside or on the surface of the stator core that is generated by the stator coil and does not interfere with the dense portion of the magnetic flux lines passing through the stator core,
The rotor is
A case portion having an open end on the stator coil installation side of the stator core, while storing the stator core around which the stator coil is wound,
A cover part that is installed at an opening end of the case part and forms a housing case for sealing the stator core in cooperation with the case part;
With
A rotary electric machine characterized in that a space formed between the housing case and a stator core around which the stator coil is wound is a second refrigerant flow path.

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