Rotary electric machine

Abstract

This rotary electric machine includes: a stator having an annular stator core having a slot into which a coil is inserted and a flow path through which a cooling fluid for cooling a coil end of the coil flows; and a rotor. The flow path is composed of a coil end cover covering the coil end and a connection plate part constituting a part of a radially outer side surface of the flow path. The connection plate part has a conductor exposure part electrically connected to the coil and provided so as to protrude outward in the radial direction. A temperature sensor is attached to the conductor exposure part.

Description

Rotating electrical machine

[0001] The present invention relates to a rotating electrical machine.

[0002] For example, Patent Document 1 below discloses a configuration of a rotating electrical machine having a cover covering an axial end face of a stator core and a terminal block disposed through the cover.

[0003] Japanese Patent Application Laid-Open No. 2010-226841

[0004] Regarding a thermistor for detecting the temperature of a rotating electrical machine, when the installation location is in the motor chamber, since the air in the motor chamber has a greater thermal resistance than the outside air, the influence on the thermistor is minor. However, if the thermistor comes into contact with the cooling oil circulating in the motor chamber, there is a possibility of measurement error in the thermistor. Also, there is a possibility that the thermistor itself may obstruct the cooling oil flowing near the coil end, or that the thermistor may fall off the mounting part depending on the routing of the lead wires of the thermistor and the flow of the oil. In view of this, an object of the present invention is to provide a rotating electrical machine that achieves both ensuring the detection accuracy of the coil temperature and cooling by oil cooling.

[0005] A rotating electrical machine comprising a stator having an annular stator core with slots through which coils are inserted and a flow path through which a cooling fluid for cooling the coil ends of the coils flows, and a rotor, wherein the flow path is constituted by a coil end cover covering the coil ends and a connection plate portion constituting a part of the radially outer surface of the flow path, the connection plate portion has a conductor exposed portion that is electrically connected to the coil and protrudes outward in the radial direction, and the temperature sensor is attached to the conductor exposed portion.

[0006] It is possible to provide a rotating electrical machine that achieves both ensuring the detection accuracy of the coil temperature and cooling by oil cooling.

[0007] An overall view of the cooling structure for the coil end of the stator core according to one embodiment of the present invention. An exploded view of the components related to the cooling structure for the coil end of Figure 1. A diagram illustrating the relationship between the stator core and the cuff according to one embodiment of the present invention. A cross-sectional view illustrating the relationship between the stator core, the cuff and the coil according to one embodiment of the present invention. A view of the stator core from above, excluding the coil end cover, according to one embodiment of the present invention. A cross-sectional view along A-A in Figure 5. A diagram illustrating the oil outlet of the coil end cover according to one embodiment of the present invention. A diagram illustrating the oil outlet of the coil end cover according to one embodiment of the present invention. A first modified example. A second modified example, a third modified example. A fourth modified example, a fifth modified example.

[0008] Embodiments of the present invention will be described below with reference to the drawings. The following description and drawings are illustrative for illustrating the present invention, and have been omitted and simplified as appropriate for clarity of explanation. The present invention can also be carried out in various other forms. Unless otherwise specified, each component may be singular or plural.

[0009] The positions, sizes, shapes, and ranges of the components shown in the drawings may not represent their actual positions, sizes, shapes, and ranges in order to facilitate understanding of the invention. Therefore, the present invention is not necessarily limited to the positions, sizes, shapes, and ranges disclosed in the drawings.

[0010] (One Embodiment and Overall Configuration) (Figures 1 to 3) The rotating electric machine 1 is composed of a stator and a rotor (not shown). The stator comprises an annular stator core 2 and a plurality of coils inserted into the stator core 2. The stator core 2 has slots through which the coils are inserted. The coils are, for example, U-shaped coils and have a straight portion 3a (Figure 4) that penetrates the slots of the stator core 2 and coil ends 3 that are exposed to the outside of the stator core 2. The coil ends 3 shown are, for example, the coil ends that are visible from the side of the stator core 2 into which the coils are inserted when a plurality of U-shaped coils are passed through the stator core 2.

[0011] A cuff 7 is provided between the coil end 3 and the stator core 2, filling the gap formed between the stator core 2 and the coil end 3, thereby preventing the coil end 3 from being positioned in a floating state relative to the stator core 2. The cuff 7 also constitutes part of the cooling fluid flow path 10, which will be described later. The coil end 3 is electrically connected to a connection plate portion 6, which forms part of the radially outer surface of the flow path 10. The connection plate portion 6 comprises a conductor electrically connected to the coil (coil end 3) and an insulator covering the conductor. The connection plate portion 6 also has a conductor exposure portion 5 that protrudes radially outward from the rotating electric machine 1. The connection plate portion 6 also constitutes part of the radially outer surface of the flow path 10.

[0012] A temperature sensor (not shown) is attached to the exposed conductor portion 5. The connection plate portion 6 has a cylindrical portion 6a along the circumferential direction of the side surface in the rotation axis direction of the stator core 2. The cylindrical portion 6a is integral with the portion of the connection plate portion 6 that is made of an insulator. The cylindrical portion 6a is also integral with a fluid pipe 9 that flows cooling fluid into the coil end 3. Thus, the fluid pipe 9 functions as an inlet or outlet for the cooling fluid that flows into the flow path 10. The exposed conductor portion 5 is provided radially outward from the cylindrical portion 6a.

[0013] The coil end 3 is necessary to improve the cooling performance of the rotating electric machine 1 by circulating a cooling fluid, such as cooling oil, to the area where the coil end 3 is located. Therefore, a coil end cover 4 is provided in the stator core 2 so as to cover the coil end 3, forming a flow path 10 for the cooling fluid to circulate. The coil end cover 4 is made of resin, for example. The flow path 10 for the cooling fluid circulating to the coil end 3 is composed of a connection plate 6, a coil end cover 4, and a cuff 7. The flow path 10 is filled with the cooling fluid circulating inside.

[0014] Thus, because the stator has the structure of the flow path 10, the coil end 3 can be immersed in the cooling fluid, ensuring that the coil is cooled reliably. Furthermore, by providing the structure of the connection plate section 6 on the rotating electric machine 1, the assembly of the coil end cover 4 that forms the flow path 10 becomes easier, and the accuracy of the assembly is also improved. In addition, the positioning of the fluid pipe 9 can be completed before the assembly of the coil end cover 4, improving work efficiency.

[0015] With the above configuration, the temperature sensor attached to the exposed conductor portion 5 is isolated from the cooling fluid flowing through the channel 10 and therefore does not come into contact with the cooling fluid. This suppresses the possibility of the temperature sensor coming into contact with the cooling fluid and causing fluctuations in the temperature sensor's measurement signal, and stabilizes the controllability of the temperature sensor. As a result, it is possible to improve the detection accuracy of the coil temperature detected by the temperature sensor while also achieving an oil-cooled structure.

[0016] (Figure 4) Figure 4 is an enlarged cross-sectional view of a portion of the circumferential direction of the stator core 2, in order to explain the relationship between the stator core 2 and the coil that penetrates the stator core 2.

[0017] The straight section 3a of the coil passes through the stator core 2. An insulator 8 is provided between the straight section 3a and the stator core 2, thereby ensuring insulation between the coil and the stator core 2. The insulator 8 has a protrusion 8a that engages with the through-hole of the coil in the stator core 2. The cuff 7 is provided between the coil end 3 and the stator core 2. The insulator 8 is also provided with its protrusion 8a sandwiched between the cuff 7 and the stator core 2.

[0018] Since the coil end 3 has a curved portion 3b in the U-shaped coil, when the coil is passed through the slot of the stator core 2, this curved portion 3b applies stress (load) to the cuff 7. The part of the cuff 7 that receives the load from the curved portion 3b of the coil end 3 is designated as the coil support portion 7c. As the coil support portion 7c receives the load, stress is also applied to the protruding portion 8a of the insulator 8 located below it, thus preventing damage to the protruding portion 8a and stably holding the cuff 7 and insulator 8. Furthermore, with this configuration, the coil end 3 does not float away from the cuff 7, so it is reliably immersed in the cooling fluid in the flow path 10, and the coil can be reliably cooled.

[0019] (Figures 5 and 6) The cuff 7 is connected to the cylindrical portion 6a of the connection plate portion 6 and to the coil end cover 4, respectively. Specifically, the cuff connection portion 6b, which is a protrusion on the cylindrical portion 6a facing the cuff 7, and the first connection portion 7a, which is a recess on the cuff 7 relative to the cylindrical portion 6a, are connected to each other. In addition, the cuff connection portion 4a, which is a protrusion on the coil end cover 4 facing the cuff 7, and the second connection portion 7b, which is a recess on the cuff 7 relative to the coil end cover 4, are connected to each other.

[0020] Thus, the cuff 7 has a recess relative to the connection surface with the coil end cover 4 and the cylindrical portion 6a, and the coil end cover 4 and the cylindrical portion 6a have a protrusion relative to this recess, forming a labyrinth structure with concave and convex parts to fit the members together. This suppresses the destruction of the connection structure due to shear, tension, or splitting in the up, down, left, and right directions, while strengthening the adhesion through compression. Furthermore, it is possible to improve the adhesive strength of the seal and adhesive material. The bonding area can be made larger, and the direction of pressure application can be compression rather than shear or tension.

[0021] (Figures 7 and 8) Figure 7 is a view of the coil end cover 4 from the stator core 2 side in Figure 1. Figure 8(a) is a cross-sectional view illustrating the oil outlet in the coil end cover 4, and Figure 8(b) is a view of Figure 8(a) from the radial direction.

[0022] The cooling fluid 14 flowing inside the coil end cover 4 cools the coil end 3 and then flows out to the outside of the coil end cover 4 through an oil outlet 11 on the coil end cover 4. Figure 8(a) illustrates the cooling fluid 14 flowing out to the outside of the coil end cover 4 from the oil outlet 11. In the coil end cover 4, the oil outlet 11 is located in a position where the cooling fluid is released into the rotating electric machine 1 without being connected to a fluid pipe 9. Specifically, as shown in Figure 8(b), the oil outlet 11 is located in the coil end cover 4 at or near the upper vertical position.

[0023] As a result, air bubbles are less likely to accumulate in the cooling fluid 14 flowing through the flow path 10, and even when the operation of the electric oil pump (not shown) that circulates the cooling fluid is stopped, the filling state of the cooling fluid 14 in the coil end cover 4 is maintained. Therefore, for example, the operation of the electric oil pump can be stopped when the output of the rotating electric machine 1 is low.

[0024] (First Modified Example) (Figure 9) Figure 9(a) is a cross-sectional view of the stator core 2 showing the structure of the gap protection wall according to the first modified example, Figure 9(b) is a diagram showing the flow direction of the cooling fluid when the gap protection wall structure shown in Figure 9(a) is provided, and Figure 9(c) is a diagram showing the flow direction of the cooling fluid when the gap protection wall structure shown in Figure 9(a) is not provided.

[0025] As shown in Figure 9(a), in the rotation axis direction of the rotating electric machine 1, the coil end cover 4 is provided with a gap protection wall 4b located outside the position where the oil outlet 11 is provided. The gap protection wall 4b is a structure that prevents the cooling fluid circulating inside the coil end cover 4 from flowing out of the coil end cover 4 from the oil outlet 11 beyond the gap protection wall 4b in the axial direction of the rotation axis. The gap protection wall 4b is formed by extending radially outward from the coil end cover 4.

[0026] This allows the flow of the cooling fluid to be restricted, as shown in the flow direction 16 of the cooling fluid that has leaked out of the coil end cover 4 as shown in Figure 9(b). With this configuration, cases will not occur where the cooling fluid that has axially escaped from the oil outlet 11 travels along the surface of the coil end cover 4 and heads towards the gap, which is the gap between the stator core 2 and the rotor provided inside it, as shown in the flow direction 16a of the cooling fluid when there is no gap protection wall 4b as shown in Figure 9(c).

[0027] (Second and third modified examples) (Figure 10) Figure 10(a) shows the relationship between the gap protection wall and the base with the exposed conductor portion according to the second modified example, and Figure 10(b) is a cross-sectional view of a rotating electric machine illustrating the thermistor protection wall that protects the exposed conductor portion and a temperature sensor (not shown) according to the third modified example.

[0028] As shown in Figure 10(a), the coil end cover 4 is equipped with a gap protection wall 4b formed radially outward. This is expected to have the effect of preventing the cooling fluid 14 that flows out from the inside of the coil end cover 4 to the outside from flowing into the gap between the stator core 2 and the rotor, as described above. Here, the cooling fluid 14 that flows out from the inside of the coil end cover 4 to the outside flows in the region between the gap protection wall 4b and the housing 12, with the gap protection wall 4b and the housing 12 acting as side walls, but it flows in the vicinity of the exposed conductor portion 5 for mounting the temperature sensor. Therefore, it is necessary to prevent the cooling fluid 14 from coming into contact with the exposed conductor portion 5 and the temperature sensor. To this end, a base 13 is provided which is integrally formed with the insulator of the connection plate portion 6 in order to protect the exposed conductor portion 5 provided on the outside of the coil end cover 4 from the cooling fluid 14. The exposed conductor portion 5 is exposed at the top of the base 13.

[0029] The base 13 is formed by extending a predetermined length radially outward from the coil end cover 4. Furthermore, in the radial direction of the rotation axis, the length of the base 13 from the coil end cover 4 is longer than the length of the gap protection wall 4b from the coil end cover 4. Figure 10(a) illustrates the difference in length H between the base 13 and the gap protection wall 4b. In this way, because the base 13 is formed to extend outward beyond the gap protection wall 4b in the radial direction of the rotation axis, the exposed conductor portion 5 and the temperature sensor are positioned above the oil level of the cooling fluid 14, thus reducing the possibility of the exposed conductor portion 5 and the temperature sensor coming into contact with the cooling fluid 14. Therefore, the base 13 can protect the exposed conductor portion 5 and the temperature sensor.

[0030] As shown in Figure 10(b), a thermistor protection wall 15 is formed between the exposed conductor portion 5 and the base 13 and the oil outlet 11 formed in the coil end cover 4. The thermistor protection wall 15 is part of the connection plate portion 6 and is a resin wall formed integrally with the insulating portion of the connection plate portion 6. With this configuration, the thermistor protection wall 15 can protect the exposed conductor portion 5 and the temperature sensor so that the cooling fluid 14 that flows out from the inside to the outside of the coil end cover 4 through the oil outlet 11 does not come into contact with the exposed conductor portion 5 and the temperature sensor. In addition, this protects the exposed conductor portion 5 and the temperature sensor from oil splashes of the cooling fluid 14 that are generated when the rotating electric machine 1 vibrates.

[0031] (Fourth modified example, fifth modified example) (Figure 11) Figure 11(a) is a diagram illustrating the structure of the coil end cover 4 according to the fourth modified example, and Figure 11(b) is a diagram illustrating the structure of the coil end cover 4 according to the fifth modified example.

[0032] As shown in Figure 11(a), the connection plate portion 6 includes a circumferential connection plate portion 6c in which the aforementioned cylindrical portion 6a (Figure 2) is formed around the entire circumference. This shape of the connection plate portion 6 eliminates the need for axial bonding structures to the coil end cover 4 and stator core 2, thus creating component boundaries that facilitate bonding between components and simplifying assembly. Furthermore, it improves the cooling performance in the area of ​​the coil end 3 where the three-phase terminals tend to heat up.

[0033] As shown in Figure 11(b), the rotor 17 may emit oil spray 14a (splashes of cooling fluid 14) from the cooling fluid that cools the rotor 17 outward in the axial direction, and it is necessary to protect the exposed conductor portion 5 and the temperature sensor from this oil spray 14a. For this reason, the coil end cover 4 may be formed to extend outward beyond the positions of the exposed conductor portion 5 and the temperature sensor in the axial direction of the rotating shaft 1a of the rotating electric machine.

[0034] As a result, in the axial direction of the rotating shaft 1a, the coil end cover 4 can protect the exposed conductor portion 5 and the temperature sensor from the oil spray 14a ejected from the rotor 17. Furthermore, by positioning the exposed conductor portion 5 inward from the connection plate portion 6 in the axial direction of the rotating shaft 1a, the likelihood of further protection from the oil spray 14a ejected from the rotor 17 is increased.

[0035] According to the embodiments of the present invention described above, the following effects and advantages are achieved.

[0036] (1) A rotating electric machine 1 comprising a rotor and a stator having an annular stator core 2 having slots through which coils are inserted and a flow path 10 through which a cooling fluid 14 for cooling the coil ends 3 of the coils flows, wherein the flow path 10 is composed of a coil end cover 4 that covers the coil ends 3 and a connection plate portion 6 that forms part of the radially outer surface of the flow path 10, and the connection plate portion 6 has a conductor exposed portion 5 that is electrically connected to the coil and protrudes radially outward, and a temperature sensor is attached to the conductor exposed portion 5. In this way, a rotating electric machine 1 can be provided that achieves both accurate detection of coil temperature and cooling by oil cooling.

[0037] (2) The connection plate portion 6 has a conductor electrically connected to the coil and an insulator covering the conductor, the insulator having a cylindrical portion 6a, and the conductor exposed portion 5 is provided on the outside of the cylindrical portion 6a in the radial direction. This protects the temperature sensor from the cooling fluid 14.

[0038] (3) A cuff 7 is provided between the coil end 3 and the stator core 2, and the flow path 10 is composed of the connecting plate portion 6, the coil end cover 4 and the cuff 7, and the flow path 10 is filled with cooling fluid 14, and the cuff 7 has a coil receiving portion 3c that receives the load from the curved portion 3b of the coil, and the coil is placed in the cooling fluid 14. In this way, each component related to the cuff 7 can be held stably.

[0039] (4) The insulator of the connection plate portion 6 and the fluid pipe 9 that allows the cooling fluid 14 to flow into the coil end 3 are formed as a single unit. This improves the assembly accuracy of the coil end cover 4.

[0040] (5) The cuff 7 has recesses on the connection surface with the wiring plate portion 6 and the connection surface with the coil end cover 4, and the wiring plate portion 6 and the coil end cover 4 each have protrusions that connect to the recesses. This improves the adhesive strength between the members.

[0041] (6) The coil end cover 4 has an oil outlet 11 that allows the cooling fluid 14 flowing through the passage 10 to flow out of the coil end cover 4. The oil outlet 11 is not connected to the fluid pipe 9 that allows the cooling fluid 14 to flow through the passage 10, and is positioned to allow the cooling fluid 14 to flow into the inside of the rotating electric machine 1. This configuration prevents air bubbles from accumulating in the cooling fluid 14 and maintains cooling even when the electric oil pump is stopped.

[0042] (7) The oil outlet 11 is located on the upper side in the vertical direction or nearby, and the coil end cover 4 has a gap protection wall 4b that is located on the outside of the coil end cover 4 in the axial direction of the rotating shaft and extends radially outward. This prevents the cooling fluid 14 from entering the gap.

[0043] (8) The exposed conductor portion 5 is exposed on a base 13 which is integrally formed with the insulator of the connection plate portion 6, and the base 13 is formed to extend outward from the gap protection wall 4b in the radial direction of the rotation axis. This reduces the possibility of the exposed conductor portion 5 and the temperature sensor coming into contact with the cooling fluid 14.

[0044] A resin wall 15 integral with the insulator of the connection plate portion 6 is provided between the pedestal 13 and the oil outlet 11. By doing so, it is possible to prevent the conductor exposed portion 5 and the temperature sensor from coming into contact with the cooling fluid 14.

[0045] A rotating electrical machine includes a stator having an annular stator core 2 having a coil and a slot through which the coil is inserted and a flow path 10 through which a cooling fluid 14 for cooling the coil ends 3 of the coil flows, and a rotor. The flow path 10 is constituted by a coil end cover 4 covering the coil end 3 and a connection plate portion 6c formed in a circumferential direction on the radially outer surface of the flow path 10. The connection plate portion 6 has a conductor exposed portion 5 that is electrically connected to the coil and protrudes outward in the radial direction. The temperature sensor is attached to the conductor exposed portion 5. The flow path 10 is filled with the cooling fluid 14, and the coil is disposed in the cooling fluid 14. By doing so, the adhesiveness between the coil end cover 4 and the connection plate portion 6c is improved.

[0046] A rotating electrical machine includes a stator having an annular stator core 2 having a coil and a slot through which the coil is inserted and a flow path 10 through which a cooling fluid 14 for cooling the coil ends 3 of the coil flows, and a rotor. The flow path 10 is constituted by a coil end cover 4 covering the coil end 3 and a connection plate portion 6 constituting a part of the radially outer surface of the flow path 10. The connection plate portion 6 has a conductor exposed portion 5 that is electrically connected to the coil and protrudes outward in the radial direction. The temperature sensor is attached to the conductor exposed portion 5. The coil end cover 4 is formed to extend outward in the axial direction of the rotating shaft beyond the positions of the conductor exposed portion 5 and the temperature sensor. By doing so, it is possible to prevent the oil spray 14a of the cooling fluid 14 from coming into contact with the conductor exposed portion 5 and the temperature sensor.

[0047] Note that the present invention is not limited to the above-described embodiments, and various modifications and other configurations can be combined without departing from the gist thereof. Further, the present invention is not limited to those having all the configurations described in the above embodiments, and also includes those in which a part of the configuration is deleted.

[0048] 1 Rotating electric machine 1a Rotating shaft 2 Stator core 3 Coil end 3a Straight section 3b Curved section 3c Coil support section 4 Coil end cover 4a Cuff connection section (protrusion) 4b Gap protection wall 5 Conductor exposed section 6 Connection plate section 6a Cylindrical section 6b Cuff connection section (protrusion) 6c Circular connection plate section 7 Cuff 7a First connection section (first recess) 7b Second connection section (second recess) 7c Coil support section 8 Insulator 8a Protrusion 9 Fluid tube 10 Flow path 11 Oil outlet 12 Housing 13 Base 14 Cooling fluid 14a Oil spray 15 Thermistor protection wall 16 Direction of cooling fluid flow 16a Direction of cooling fluid flow without protection wall 17 Rotor

Claims

1. A rotating electric machine comprising a rotor and a stator having an annular stator core having slots through which coils are inserted and a flow path through which a cooling fluid flows to cool the coil ends of the coils, wherein the flow path is composed of a coil end cover that covers the coil ends and a connection plate portion that constitutes a part of the radially outer surface of the flow path, the connection plate portion has a conductor exposure portion that is electrically connected to the coils and protrudes radially outward, and a temperature sensor is attached to the conductor exposure portion.

2. The rotating electric machine according to claim 1, wherein the connection plate portion comprises a conductor electrically connected to the coil and an insulator covering the conductor, the insulator having a cylindrical portion, and the conductor exposure portion being provided radially outside the cylindrical portion.

3. A cuff is provided between the coil end and the stator core, the flow path is composed of the connection plate portion, the coil end cover and the cuff, and the flow path is filled with the cooling fluid, the cuff has a coil support portion that receives the load from the curved portion of the coil, and the coil is disposed in the cooling fluid, as described in claim 2.

4. The rotating electric machine according to claim 3, wherein the insulator of the connection plate portion and the fluid pipe for supplying the cooling fluid to the coil end are integrally formed.

5. The rotating electric machine according to claim 3, wherein the cuff has recesses on the connection surface with the wiring plate portion and the connection surface with the coil end cover, and the wiring plate portion and the coil end cover each have protrusions that connect to the recesses.

6. The rotating electric machine according to claim 2, wherein the coil end cover has an oil outlet that causes the cooling fluid flowing through the passage to flow out to the outside of the coil end cover, the oil outlet is not connected to a fluid pipe that causes the cooling fluid to flow through the passage, and is provided in a position that causes the cooling fluid to flow into the inside of the rotating electric machine.

7. The rotating electric machine according to claim 6, wherein the oil outlet is provided on the upper side in the vertical direction or in its vicinity, and the coil end cover has a gap protection wall provided on the outside of the coil end cover in the axial direction of the rotating shaft and extending radially outward from the rotating shaft.

8. The rotating electric machine according to claim 7, wherein the exposed conductor portion is exposed on a base formed integrally with the insulator, and the base is formed to extend outward from the gap protection wall in the radial direction of the rotation shaft.

9. The rotating electric machine according to claim 8, wherein a resin wall integral with the insulator is provided between the base and the oil outlet.

10. A rotating electric machine comprising a rotor and a stator having an annular stator core having a coil and a slot through which the coil is inserted, and a passage through which a cooling fluid flows to cool the coil ends of the coil, wherein the passage is composed of a coil end cover that covers the coil ends and a connection plate portion formed circumferentially for a full circumference on the radially outer surface of the passage, the connection plate portion has a conductor exposure portion that is electrically connected to the coil and protrudes radially outward, a temperature sensor is attached to the conductor exposure portion, the passage is filled with the cooling fluid, and the coil is disposed in the cooling fluid.

11. A rotating electric machine comprising a rotor and a stator having an annular stator core having a coil and a slot through which the coil is inserted, and a flow path through which a cooling fluid flows to cool the coil end of the coil, wherein the flow path is composed of a coil end cover covering the coil end and a connection plate portion forming a part of the radially outer surface of the flow path, the connection plate portion having a conductor exposure portion that is electrically connected to the coil and protrudes radially outward, a temperature sensor is attached to the conductor exposure portion, and the coil end cover is formed to extend outward in the axial direction of the rotating shaft beyond the positions of the conductor exposure portion and the temperature sensor.

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