(19)
(11)EP 3 764 524 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
27.07.2022 Bulletin 2022/30

(21)Application number: 19764130.1

(22)Date of filing:  26.02.2019
(51)International Patent Classification (IPC): 
H02K 9/02(2006.01)
H02K 5/20(2006.01)
H02K 9/19(2006.01)
(52)Cooperative Patent Classification (CPC):
H02K 9/19; H02K 9/02; H02K 5/203; H02K 5/207
(86)International application number:
PCT/JP2019/007163
(87)International publication number:
WO 2019/172007 (12.09.2019 Gazette  2019/37)

(54)

DYNAMO-ELECTRIC MACHINE

DYNAMO-ELEKTRISCHE MASCHINE

MACHINE DYNAMOÉLECTRIQUE


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 09.03.2018 JP 2018042614

(43)Date of publication of application:
13.01.2021 Bulletin 2021/02

(73)Proprietor: Meidensha Corporation
Tokyo 141-6029 (JP)

(72)Inventor:
  • KAWANISHI, Kota
    Tokyo 141-6029 (JP)

(74)Representative: Manitz Finsterwald Patent- und Rechtsanwaltspartnerschaft mbB 
Martin-Greif-Strasse 1
80336 München
80336 München (DE)


(56)References cited: : 
CN-A- 107 147 260
DE-A1- 19 949 137
JP-A- 2001 045 713
JP-A- 2013 207 944
JP-U- S6 370 260
DE-A1- 10 122 425
JP-A- H08 322 188
JP-A- 2002 186 221
JP-U- H0 644 378
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    TECHNICAL FIELD



    [0001] The present invention relates to a dynamo-electric machine such as a generator and an electric motor.

    BACKGROUND ART



    [0002] In a dynamo-electric machine such as a large-sized generator and a large-sized electric motor for which high output (high power) and high speed rotation are required, since a thick high-voltage insulating paper is used at an inside of a stator and a winding portion such as a coil end in response to the high output and also a magnet of a rotor is fixed to a rotation shaft with the magnet being surrounded with a ring in response to the high speed rotation, there is a tendency for the winding portion of the stator and a magnet portion of the rotor not to easily radiate or release heat, then this causes an increase in temperature.

    [0003] For this problem, for instance, the following Patent Document 1 has proposed that the stator and the rotor should be cooled by providing a water-cooling jacket between a frame and the stator, forming a ventilation path between the water-cooling jacket and the frame, making cooling water flow in the water-cooling jacket and making air inside the frame circulate through the ventilation path.

    CITATION LIST


    PATENT DOCUMENT



    [0004] 

    Patent Document 1: Japanese Unexamined Patent Application Publication No. 2011-211816

    Patent Document 2: Japanese Unexamined Patent Application Publication No. 2008-301646



    [0005] CN 107 147 260 A discloses a high-speed reluctance motor comprising two stators and two rotors, and a circumferential circuit air duct which is a different member from these stators and rotors is provided in a cooling cavity formed between the stators and the rotors . DE 199 49 137 A1 teaches an AC generator which provides cooling sections to cool the generator during operation. In particular, cooling chambers and air vents are used to carry cooling fluid or air. DE 101 22 425 A1 relates to an electric machine which uses a water cooled stator and an air cooled rotor. JP 2001 045713 A discloses an electric machine which comprises a stator core comprising laminated stator iron plates, which is divided axially into a plurality of divided stator cores, wherein the divided stator cores are inserted into a cylindrical housing.

    SUMMARY OF THE INVENTION


    TECHNICAL PROBLEM



    [0006] According to demands for an even higher output and an even higher speed rotation, further improvement in cooling performance has been strongly required for such large-sized dynamo-electric machine described above.

    [0007] Hence, an object of the present invention is to provide a large-sized dynamo-electric machine having an improved cooling performance.

    SOLUTION TO PROBLEM



    [0008] This object is satisfied by the subject-matter of claim 1.

    [0009] In order to meet the above demands, a dynamo-electric machine of the present invention comprises: a cylindrical frame; a cylindrical stator fixed to an inside of the frame; a cylindrical rotor provided inside the stator such that a gap is formed between the rotor and the stator; a rotation shaft fixed to the rotor so as to penetrate an inside of the rotor; and a bracket fixed to the frame and rotatably supporting the rotation shaft, wherein ducts are radially formed at the stator at a middle portion in an axial direction of the stator so as to directly communicate with the gap, and the frame has first supply openings through which cooling air flow is supplied in the frame at axial direction both end sides of the frame, exhaust openings through which cooling air flow in the frame is exhausted to an outside of the frame at axial direction both end sides of the frame and the cooling air flow (1) through said second supply openings (17) is supplied to the ducts of the stator, wherein the second supply openings are arranged at opposite each other on the peripheral surface of the frame.

    [0010] The dynamo-electric machine of the present invention further comprises: cooling-water pipes provided as a pair at one end side and the other end side of a middle in the axial direction of the frame, wherein the cooling-water pipes have, at the middle in the axial direction of the frame, inlets through which cooling water is supplied to the cooling-water pipes and have, at the axial direction both end sides of the frame, outlets through which the cooling water is exhausted from the cooling-water pipes, the second supply openings are located between the inlets of the both cooling-water pipes, whereby cooling air flow being supplied from the second supply openings, flows in the ducts of the stator while cooling the stator from the middle portion and reaches the gap .

    [0011] In the dynamo-electric machine of the present invention, the frame is an aluminum metal-made frame having the cooling-water pipes between an outer peripheral surface and an inner peripheral surface of the frame by casting.

    EFFECTS OF INVENTION



    [0012] When supplying the cooling air flow into the first and second supply openings of the dynamo-electric machine of the present invention, the cooling air flow supplied from the first supply opening flows to the both end sides in the axial direction in the frame while cooling coil ends etc., and is exhausted to the outside of the frame from the exhaust opening. The cooling air flow supplied from the second supply opening flows in the duct of the stator while cooling the stator from the middle portion in the axial direction of the stator, and reaches the gap. This cooling air flow branches off from the axial direction middle portion, further flows in the gap toward the both end sides of the frame while cooling an inner peripheral surface of the stator and an outer peripheral surface of the rotor, flows out from the gap, and is exhausted to the outside of the frame from the exhaust opening.

    [0013] Therefore, according to the dynamo-electric machine of the present invention, not only the coil ends can be cooled, but also an inside of the axial direction middle portion of the stator, which is highest in temperature at the stator, can be air-cooled from a radial direction outer side to a radial direction inner side, and further the inner peripheral surface of the stator and an outer peripheral surface of the rotor can be air-cooled from the axial direction middle portion to the both end sides. Hence, even in a case where a thick high-voltage insulating paper is used at the inside of the stator and winding portions such as the coil ends in response to the high output and also the rotor is fixed to the rotation shaft with a permanent magnet being surrounded with a ring in response to the high speed rotation, the inside of the stator, the winding portions such as the coil ends and the permanent magnet of the rotor are effectively cooled, and the temperature increase can be greatly suppressed.

    [0014] Accordingly, according to the dynamo-electric machine of the present invention, the cooling performance is further improved, and even higher output and even higher speed rotation can be achieved.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0015] 

    Fig. 1 is an external view of a main part of a dynamo-electric machine according to a main embodiment of the present invention.

    Fig. 2 is a schematic sectional view of the dynamo-electric machine shown in Fig. 1.

    Fig. 3 is a drawing showing structures of cooling-water pipes of the dynamo-electric machine shown in Figs. 1 and 2.

    Fig. 4 is a drawing for explaining supply and exhaust directions of cooling water and cooling air flow of the dynamo-electric machine shown in Fig. 1.

    Fig. 5 is a drawing for explaining flow directions of the cooling air flow of the dynamo-electric machine shown in Fig. 2.


    EMBODIMENTS FOR CARRYING OUT THE INVENTION



    [0016] An embodiment of a dynamo-electric machine according to the present invention will be explained below with reference to the drawings. However, the present invention is not limited to the following embodiment explained using the drawings.

    <Main embodiment>



    [0017] Amain embodiment of the dynamo-electric machine according to the present invention will be explained with reference to Figs. 1 to 5.

    [0018] As shown in Figs. 1 and 2, an outer peripheral surface of a cylindrical stator 12 is fixed to an inner peripheral surface at a middle in an axial direction of a cylindrical hollow-shaped frame 11 made of aluminum metal, which is high heat transfer material, so that the stator 12 is coaxial with the frame 11. Further, a rotation shaft 14 is provided so as to penetrate an inside of the stator 12 and be coaxial with the stator 12. The rotation shaft 14 is rotatably supported, at both end sides thereof, by a pair of annular brackets 15 that are fixed to both end sides of the frame 11.

    [0019] A permanent magnet 13a is provided on an outer peripheral surface at a middle in the axial direction of the rotation shaft 14 throughout an entire circumference of the rotation shaft 14 so as to face an inner peripheral surface of the stator 12. Further, a cylindrical ring 13b that is made of iron or the like having magnetism is fitted so as to fix the permanent magnet 13a on the outer peripheral surface of the rotation shaft 14. The permanent magnet 13a and the ring 13b etc. form a rotor 13. In other words, the rotation shaft 14 is fixed to the rotor 13 so as to penetrate an inside of the rotor 13. The rotor 13 is provided inside the stator 12 such that a gap G having a specified distance is formed between the inner peripheral surface of the stator 12 and an outer peripheral surface of the ring 13b.

    [0020] At both end sides in the axial direction on a peripheral surface of the frame 11, first supply openings 16 and exhaust openings 18 through which an inside and an outside of the frame 11 communicate with each other are formed so as to face each other. At a middle in the axial direction on the peripheral surface of the frame 11, a plurality of second supply openings (in the present embodiment, two second supply openings) 17 through which ducts 12a that are radially formed at a middle portion in the axial direction of the stator 12 and that communicate with the gap G and the outside of the frame 11 communicate with each other are formed at regular intervals along a circumferential direction of the frame 11.

    [0021] Further, at a middle in the axial direction between an outer peripheral surface and an inner peripheral surface of the frame 11, helical stainless (SUS) cooling-water pipes 21A and 21B (see Fig. 3) are formed by casting such that these cooling-water pipes 21A and 21B are arranged as a pair at one end side and the other end side of the middle of the frame 11. The cooling-water pipes 21A and 21B have inlets 21Aa and 21Ba respectively that are exposed to the outside of the frame 11 at lower positions at the middle in the axial direction of the frame 11. The cooling-water pipes 21A and 21B also have outlets 21Ab and 21Bb respectively that are exposed to the outside of the frame 11 at upper positions at the both end sides in the axial direction of the frame 11.

    [0022] In the drawing, reference signs 19 denote coil ends.

    [0023] In such dynamo-electric machine 10 of the present embodiment, as depicted in Fig. 4, cooling air flows 1 are supplied into the frame 11 from the first and second supply openings 16 and 17, and cooling waters 2 are supplied to the cooling-water pipes 21A and 21B from the inlets 21Aa and 21Ba.

    [0024] Then, as depicted in Fig. 5, the cooling air flows 1 supplied from the first supply openings 16 flow to the both end sides in the axial direction in the frame 11 while cooling the coil ends 19 etc., and are exhausted to the outside of the frame 11 from the exhaust openings 18. The cooling air flows 1 supplied from the second supply openings 17 flow in the ducts 12a of the stator 12 while cooling the stator 12 from the middle portion in the axial direction of the stator 12, and reach the gap G. These cooling air flows 1 branch off from the axial direction middle portion, and further flow in the gap G toward the both end sides of the frame 11 while cooling the inner peripheral surface of the stator 12 and an outer peripheral surface of the rotor 13. The cooling air flows 1 flowing out from the gap G join or meet the cooling air flows 1 supplied from the first supply openings 16, and are exhausted to the outside of the frame 11 from the exhaust openings 18.

    [0025] On the other hand, the cooling waters 2 supplied from the inlets 21Aa and 21Ba flow in the cooling-water pipes 21A and 21B. That is, the cooling waters 2 cool almost all the stator 12 from an outer peripheral surface of the stator 12 through the frame 11 while helically flowing on the outer peripheral surface of the stator 12 from the axial direction middle to the both end sides of the stator 12, and are exhausted from the outlets 21Ab and 21Bb.

    [0026] That is to say, in the dynamo-electric machine 10 according to the present embodiment, not only the coil ends 19 are cooled by the cooling air flows 1 supplied from the first supply openings 16, but also an inside of the axial direction middle portion of the stator 12, which is highest in temperature at the stator 12, is air-cooled from a radial direction outer side to a radial direction inner side by the cooling air flows 1 supplied from the second supply openings 17, and further the inner peripheral surface of the stator 12 and an outer peripheral surface of the rotor 13 are air-cooled from the axial direction middle portion to the both end sides by the cooling air flows 1 supplied from the second supply openings 17. Moreover, by the cooling waters 2 supplied from the inlets 21Aa and 21Ba, the outer peripheral surface of the stator 12 is water-cooled from the axial direction middle portion of the stator 12, which is highest in temperature at the stator 12, to the both end sides of the stator 12.

    [0027] Hence, in the dynamo-electric machine 10 of the present embodiment, even in a case where a thick high-voltage insulating paper is used at the inside of the stator 12 and winding portions such as the coil ends 19 in response to the high output and also the rotor 13 is fixed to the rotation shaft 14 with the permanent magnet 13a being surrounded with the ring 13b in response to the high speed rotation, the inside of the stator 12, the winding portions such as the coil ends 19 and the permanent magnet 13a of the rotor 13 are effectively cooled, and the temperature increase can be greatly suppressed.

    [0028] Accordingly, according to the dynamo-electric machine 10 of the present embodiment, since cooling performance can be greatly improved, even higher output and even higher speed rotation can be achieved.

    [0029] Further, since the stator 12 is cooled by the cooling waters 2 flowing parallel in the two cooling-water pipes 21A and 21B, a quantity of flow (or a flow rate) per unit time of the cooling water 2 can be increased without increasing pressure loss in the cooling-water pipes 21A and 21B. Therefore, cooling performance by the cooling water 2 can be greatly improved.

    [Industrial applicability]



    [0030] The dynamo-electric machine according to the present invention is capable of achieving even higher output and even higher speed rotation by greatly improving the cooling performance. Therefore, the dynamo-electric machine of the present invention can be effectively utilized in industry.

    EXPLANATION OF REFERENCE



    [0031] 1 ··· cooling air flow, 2 ··· cooling water, 10 ··· dynamo-electric machine, 11 ··· frame, 12 ··· stator, 12a ··· duct, 13 ··· rotor, 13a ··· permanent magnet, 13b ··· ring, 14 ··· rotation shaft, 15 ··· bracket, 16 ··· first supply opening, 17 ··· second supply opening, 18 ··· exhaust opening, 19 ··· coil end, 21A, 21B ··· cooling-water pipe, 21Aa, 21Ba ··· inlet, 21Ab, 21Bb ··· outlet, G ··· gap


    Claims

    1. A dynamo-electric machine (10) comprising:

    a cylindrical frame (11);

    a cylindrical stator (12) fixed to an inside of the frame (11) ;

    a cylindrical rotor (13) provided inside the stator (12) such that a gap (G) is formed between the rotor (13) and the stator (12) ;

    a rotation shaft (14) fixed to the rotor (13) so as to penetrate an inside of the rotor (13); and

    a bracket (15) fixed to the frame (11) and rotatably supporting the rotation shaft (14),

    wherein ducts (12a) are radially formed at the stator (12) at a middle portion in axial direction of the stator (12) so as to directly communicate with the gap (G),

    the frame (11) has first supply openings (16) through which cooling air flow (1) is supplied in the frame (11) at both end sides in axial direction of the frame (11), exhaust openings (18) through which cooling air flow (1) in the frame (11) is exhausted to an outside of the frame (11) at both end sides in axial direction of the frame (11) and the cooling air flow (1) through said second supply openings (17) is supplied to the ducts (12a) of the stator (12), wherein the second supply openings (17) are arranged opposite each other on the peripheral surface of the frame (11),

    the dynamo-electric machine (10) further comprises cooling-water pipes (21A, 21B) provided as a pair at one end side and the other end side of the middle in the axial direction of the frame (11),

    wherein the cooling-water pipes (21A, 21B) have, at the middle in the axial direction of the frame (11), inlets (21Aa, 21Ba) through which cooling water (2) is supplied to the cooling-water pipes (21A, 21B) and have, at the axial direction both end sides of the frame (11), outlets (21Ab, 21Bb) through which the cooling water (2) is exhausted from the cooling-water pipes (21A, 21B),

    the second supply openings (17) are located between the inlets (21Aa, 21Ba) of the both cooling-water pipes (21A, 21B) , whereby cooling air flow (1) being supplied from the second supply openings (17), flows in the ducts (12a) of the stator (12) while cooling the stator (12) from the middle portion and reaches the gap (G).


     
    2. The dynamo-electric machine (10) as claimed in claim 1, wherein:
    the frame (11) is an aluminum metal-made frame (11) having the cooling-water pipes (21A, 21B) between an outer peripheral surface and an inner peripheral surface of the frame (11) by casting.
     


    Ansprüche

    1. Dynamoelektrische Maschine (10) umfassend:

    einen zylinderförmigen Rahmen (11);

    einen zylinderförmigen Stator (12), der an ein Inneres des Rahmens (11) befestigt ist;

    einen zylinderförmigen Rotor (13), der innerhalb des Stators (12) angebracht ist, so dass ein Spalt (G) zwischen dem Rotor (13) und dem Stator (12) gebildet ist;

    eine Drehwelle (14), die an dem Rotor (13) so befestigt ist, dass die Drehwelle ein Inneres des Rotors durchdringt; und

    einen Träger (15), der an den Rahmen (11) befestigt ist und die Drehwelle (14) drehbar trägt,

    wobei Kanäle (12a) radial an dem Stator (12) an einem mittleren Abschnitt in axialer Richtung des Stators (12) ausgebildet sind, um direkt mit dem Spalt (G) zu kommunizieren,

    wobei der Rahmen (11) erste Zuführöffnungen (16) aufweist, durch die ein Kühlluftstrom (1) in den Rahmen (11) an Seiten beider Enden in axialer Richtung des Rahmens (11) zugeführt wird, Abluftöffnungen (18) aufweist, durch die Kühlluftstrom (1) im Rahmen (11) an Seiten beider Enden in axialer Richtung des Rahmens (11) nach außen abgeführt wird, und der Kühlluftstrom (1) durch die zweiten Zuführöffnungen (17) den Kanälen (12a) des Stators (12) zugeführt wird, wobei die zweiten Zuführöffnungen (17) einander gegenüberliegend an der Umfangsfläche des Rahmens (11) angeordnet sind,

    wobei die dynamoelektrische Maschine (10) ferner Kühlwasserrohre (21A, 21B) umfasst, die als ein Paar an der Seite des einen Endes und der Seite des anderen Endes von der Mitte in der axialen Richtung des Rahmens (11) aus angebracht sind,

    wobei die Kühlwasserrohre (21A, 21B) an der Mitte in der axialen Richtung des Rahmens (11) Einlässe (21Aa, 21Ba) aufweisen, durch die den Kühlwasserrohren (21A, 21B) Kühlwasser (2) zugeführt wird, und an den Seiten beider Enden des Rahmens (11) in der axialen Richtung Auslässe (21Ab, 21Bb) aufweisen, durch die das Kühlwasser (2) aus den Kühlwasserrohren (21A, 21B) abgeführt wird,

    wobei die zweiten Zufuhröffnungen (17) zwischen den Einlässen (21Aa, 21Ba) der beiden Kühlwasserrohre (21A, 21B) angeordnet sind, wodurch Kühlluftstrom (1), der von den zweiten Zuführöffnungen (17) zugeführt wird, in die Kanäle (12a) des Stators (12) strömt, während der Stator (12) von dem mittleren Abschnitt gekühlt wird, und den Spalt (G) erreicht.


     
    2. Dynamoelektrische Maschine (10) nach Anspruch 1, wobei:
    der Rahmen (11) ein aus Aluminiummetall hergestellter Rahmen (11) ist, dessen Kühlwasserrohre (21A, 21B) zwischen einer Außenumfangsfläche und einer Innenumfangsfläche des Rahmens (11) durch Guss ausgebildet sind.
     


    Revendications

    1. Machine dynamo-électrique (10) comprenant :

    un châssis cylindrique (11) ;

    un stator cylindrique (12) fixé sur une partie intérieure du châssis (11) ;

    un rotor cylindrique (13) prévu à l'intérieur du stator (12) de telle sorte qu'un intervalle (G) est formé entre le rotor (13) et le stator (12) ;

    un arbre rotatif (14) fixé sur le rotor (13) de manière à pénétrer dans une partie inférieure du rotor (13) ; et

    un support (15) fixé sur le châssis (11) et supportant en rotation l'arbre rotatif (14),

    dans lequel des conduits (12a) sont formés radialement au niveau du stator (12) à une portion médiane dans une direction axiale du stator (12) de manière à être en communication directe avec l'intervalle (G),

    le châssis (11) a des premières ouvertures d'alimentation (16) à travers lesquelles un flux d'air de refroidissement (1) est alimenté dans le châssis (11) au niveau des deux côtés d'extrémité dans une direction axiale du châssis (11), des ouvertures d'évacuation (18) à travers lesquelles un flux d'air de refroidissement (1) dans le châssis (11) est évacué vers une partie extérieure du châssis (11) au niveau des deux côtés d'extrémité dans une direction axiale du châssis (11) et le flux d'air de refroidissement à travers lesdites secondes ouvertures d'alimentation (17) est alimenté aux conduits (12a) du stator (12), les secondes ouvertures d'alimentation (17) étant agencées en opposition les unes aux autres sur la surface périphérique du châssis (11),

    la machine dynamo-électrique (10) comprend en outre des tubes à eau de refroidissement (21A, 21B) prévus sous forme d'une paire au niveau d'un côté d'extrémité et de l'autre côté d'extrémité de la partie médiane dans la direction axiale du châssis (11),

    dans lequel les tubes à eau de refroidissement (21A, 21B) ont, au niveau de la partie médiane dans la direction axiale du châssis (11), des entrées (21Aa, 21Ba) à travers lesquelles de l'eau de refroidissement (2) est alimentée aux tubes à eau de refroidissement (21A, 21B) et ont, au niveau des deux côtés d'extrémité de direction axiale du châssis (11), des sorties (21Ab, 21Bb) à travers lesquelles l'eau de refroidissement (2) est évacuée hors des tuyaux à eau de refroidissement (21A, 21B),

    les secondes ouvertures d'alimentation (17) sont situées entre les entrées (21Aa, 21Ba) des deux tubes à eau de refroidissement (21A, 21B), grâce à quoi un flux d'air de refroidissement (1) qui est alimenté depuis les secondes ouvertures d'alimentation (17) s'écoule dans les conduits (12a) du stator (12) tout en refroidissant le stator (12) depuis la portion médiane et atteint l'intervalle (G).


     
    2. Machine dynamo-électrique (10) selon la revendication 1, dans laquelle :
    le châssis (11) est un châssis fait en métal d'aluminium (11), ayant les tubes à eau de refroidissement (21A, 21B) entre une surface périphérique extérieure et une surface périphérique intérieure du châssis (11), par moulage par coulée.
     




    Drawing




















    Cited references

    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description