JP2005168204A - Rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary electric machine having small temperature gradient for a stator coil, in which rise in the temperature of the stator coil on Lee side is reduced with the same amount of cooling air as in the conventional cases. <P>SOLUTION: The rotary electric machine comprises a stator core 1 provided inside a tubular stator frame 9, a stator coil 2 attached to the stator core 1, and a rotor 7 which is supported via a bracket 13 attached to the end of the stator frame 9 and rotates with a prescribed gap 11 from the inner peripheral surface of the stator core 1. It comprises an air taking-in window 10 which is opened at one end of the stator frame 9 and supplies a cooling air in the machine, and an air discharging opening 14 which is formed at the bracket 13 and discharges the cooling air out of the machine. A ventilation path 16 is provided outside the stator frame 9 and guides the cooling air from an air window 5, opened at the air taken-in window 10; and then supplies the cooling air into the machine from a guiding-in window 17 opened at the other end of the stator frame 9. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a rotating electrical machine used mainly as a main motor of a railway vehicle, and more particularly to a rotating electrical machine having an improved cooling structure.

  In recent years, the demand for mass transportation and high-speed traveling has been increasing for railway vehicles, and many configurations have been adopted to increase the output of the main motor that drives the railway vehicles. The size of the main motor is limited because it is installed in a narrow space in the carriage, and in order to increase the output while maintaining the size of the main motor to be the same as the conventional size, the speed of the main motor must be increased. The cooling performance needs to be improved. Here, the speedup of the main motor is limited by the strength limit due to the centrifugal force of the rotor and the lubrication limit of the bearing, and there is a limit to the dramatic speedup.

  In order to improve the cooling performance of the main motor, the self-ventilated main motor with a fan installed in the rotor has a limitation in the amount of cooling air due to the space problem in the main motor, and requires a particularly large output for locomotives. In the main motor, a dedicated cooling fan is provided outside the main motor so that strong cooling air is passed through the main motor to improve the cooling performance.

  However, since the air gap between the stator core and the rotor core is narrow in the cage main motor, it is necessary to provide a blower that can send high-pressure cooling air, which increases the size of the blower. There is. Further, since the fan noise increases in proportion to the increase in the blower performance of the blower and the air blowing capacity is limited due to noise problems, it is difficult to increase the output of the main motor by improving the cooling performance of the main motor.

  In addition, the cooling air of the forced air-cooled high-power main motor is large in both wind speed and air volume, and is particularly large in the locomotive main motor. In such a large output main motor with a large air volume, the temperature difference between the windward side and the leeward side in the main motor is large.

  As for the limit value of the coil temperature rise of the main motor for railway vehicles, H type defined by JIS is generally used and is 180K. This limit value 180K is determined at the highest temperature part, and when a temperature gradient occurs between the leeward side and the leeward side, the part where the maximum temperature is locally reached is the limit, so that the output increases. It is disadvantageous.

  In the locomotive high-power main motor, when the temperature limit value is 180K on the leeward side, the windward side is about 130K, and even if the average temperature rise is 155K, the temperature difference is as high as 50K, resulting in a gradient of about 38%. Thus, the limit value is determined on the leeward side where the temperature of the main motor becomes locally high, and it is difficult to increase the output.

  FIG. 10 shows an upper half longitudinal sectional view of a conventional locomotive main motor, and FIG. 11 shows a transverse sectional view. In these drawings, the main motor is a squirrel-cage induction motor, a stator coil 2 is wound around a stator core 1, and a rotating private iron core 3 constituting a rotor 7 is formed on a shaft 4 on the inner diameter side of the stator core 1. The rotor bar 5 is inserted into a slot of the rotor core 3 and the both ends of the rotor bar 5 are connected by a short-circuit ring 6. Both ends of the shaft 4 are supported by brackets 13 attached to the stator frame 9 by bearings 8.

  A wind intake window 10 is formed on a part of the stator frame 9 on the side opposite to the driving side, and cooling air from a blower provided outside the motor is passed through the window 10. The cooling air passes from the wind intake window 10 through the gap 11 between the inner periphery of the stator core 1 and the outer periphery of the rotor core 3 and the air hole 12 provided in the rotor core 3, and is supplied to the drive side. The discharged air outlet 14 is discharged outside the machine.

In order to obtain an output of 600 kW, for example, in a high-power main motor for a locomotive, a large cooling air volume of 50 m ³ / min is blown from the blower outside the machine, and as described above, the gap 11 and rotation from the wind intake window 10 on the non-drive side. The air hole 12 of the core 3 is ventilated and discharged from the air outlet 14 of the drive side bracket 13. The temperature rise of the stator coil is 180K, which is the insulation type H class specified by the JIS railcar main motor. The temperature distribution of the stator coil of this main motor is that the part where the temperature rise is highest is on the leeward side. The temperature becomes 180 K at the stator coil 2 portion, and the temperature decreases to 130 K as it becomes the windward side. Although the average temperature rise is 155K, the temperature gradient of the stator coil is large.

The temperature rise of the main motor directly affects the insulation life of the stator coil of the main motor, and the insulation life is affected by the temperature of the highest part, not the average temperature of each part of the stator coil, so the temperature gradient is large The main motor is disadvantageous in terms of output.
SUMMARY OF THE INVENTION An object of the present invention is to provide a rotating electrical machine that reduces the temperature rise of the stator coil on the leeward side with the same amount of cooling air as in the prior art and has a small temperature gradient of the stator coil.

  The invention of claim 1 includes a stator iron core provided inside a cylindrical stator frame, a stator coil attached to the stator iron core, and a bracket attached to an end of the stator frame. And a rotor that rotates with a predetermined gap between the stator core and the inner peripheral surface of the stator core, and opens at one end of the stator frame to supply cooling air into the machine In a rotating electrical machine having a wind intake window that is formed on the bracket and an exhaust port that discharges cooling air to the outside of the machine, the cooling air is guided from a wind window that is provided outside the stator frame and opens to the wind intake window. And a ventilation path for supplying cooling air into the machine from the introduction window opened at the other end of the stator frame.

According to a second aspect of the present invention, the wind window is formed by a partition plate provided in the wind intake window.
The invention of claim 3 includes a ring-shaped partition plate attached to the inside of the other end of the stator frame, and the distance between the inner periphery of the ring-shaped partition plate and the end of the stator coil is It is set as the structure formed smaller than the distance of the outer peripheral side edge of the said exhaust port, and the edge part of the said stator coil.

According to a fourth aspect of the present invention, the outer peripheral side edge of the air exhaust port is formed on the inner peripheral side from the bending center of the end portion of the stator coil.
According to a fifth aspect of the present invention, there is provided an arcuate rectifying plate that is attached to a side surface of the stator core and that divides the cooling air supplied from the introduction window into the machine in the circumferential direction.
According to a sixth aspect of the present invention, the current plate has a mountain shape with a long center and a short end.

  ADVANTAGE OF THE INVENTION According to this invention, the temperature increase of the stator coil of a leeward side can be reduced with the same cooling air volume as before, and the rotary electric machine with a small temperature gradient of a stator coil can be provided.

  Hereinafter, first to sixth embodiments will be described with reference to the drawings.

  As shown in the upper half longitudinal sectional view of FIG. 1 and the transverse sectional view of FIG. 2, the rotating electrical machine of this embodiment is a squirrel-cage induction motor, and a stator coil 2 is wound around a stator core 1. A rotor core 3 constituting a rotor 7 is laminated on a shaft 4 on the inner diameter side of the iron core 1, a rotor bar 5 is inserted into a slot of the rotor core 3, and both ends of the rotor bar 5 are connected by a short-circuit ring 6. ing. Both ends of the shaft 4 are supported by the stator frame 9 by bearings 8. A wind intake window 10 is provided on a part of the stator frame 9 on the side opposite to the driving side.

  Although the above configuration is the same as that of a conventional rotating electric machine, in this embodiment, a wind window 15 is further provided inside the wind intake window 10 of the stator frame 9, and the wind window 15 extends from the wind window 15 to the outer peripheral surface of the stator frame 9. A ventilation path 16 is formed along the driving frame 16 and an introduction window 17 is provided in a part of the driving side stator frame 9. The ventilation path 16 communicates the inside of the wind intake window 10 with the space inside the driving side stator frame 9. ing.

  With the configuration described above, the air from the cooling fan provided outside the rotating electrical machine is blown into the rotating electrical machine from the wind intake window 10 of the stator frame 9 through the air guide. The cooling air passes from the non-driving side in the rotating electrical machine through the windward stator coil 2 and the gap 11 and the rotor hole 3 of the rotor core 3 that are the heat generating portions, and the temperature rising wind flows to the driving side and the air outlet of the bracket 13. 14 is discharged out of the machine.

  On the other hand, a part of the cooling air blown from the blower passes from the wind window 15 provided inside the wind intake window 10 through the ventilation path 16 and directly from the introduction window 17 to the leeward side without directly passing through the heat generating portion having a high temperature. Ventilated into the aircraft. The cooling air passed through the leeward machine directly cools the stator coil 2 having a high temperature, and the heated wind is discharged from the air outlet 14 of the bracket 9 to the outside of the machine.

  By setting the air volume introduced into the ventilation path 16 so that the temperature gradient between the stator coil on the windward side and the stator coil on the leeward side is minimized, the temperature rise distribution of the stator coil 2 is shown in FIG. It becomes as shown in. The average temperature rise is 155K as in the case of the conventional rotating electric machine shown in FIG. 3B, but when the leeward side of the higher temperature is 165K, the leeward side is 145K, the temperature difference is 20K, and the temperature gradient is about It is greatly reduced to 14%. The output of the rotating electrical machine can be increased by the amount that the temperature on the leeward side has decreased.

  In the present embodiment, a wind window 15 is further provided in the wind intake window 10 of the stator frame 9, and the wind window 15 communicates with the machine in which the stator coil 2 in the stator frame 9 on the leeward side is disposed. A ventilation path 16 is provided outside the frame 9, and the cooling air flowing through the ventilation path 16 has an area that allows a part of the entire rotating electrical machine cooling air to flow.

  With the above configuration, the cooling air from the blower provided outside the rotating electrical machine is introduced from the wind intake window 10 of the stator frame 9 on the windward side, and a part of the cooling air is further provided in the window 10. 15 is introduced into the ventilation path 16 outside the stator frame 9 and directly introduced into the leeward machine, the cooling wind of the stator coil 2 on the leeward side is reduced correspondingly and the temperature is increased. The temperature of the stator coil 2 on the leeward side, which is directly introduced to the side and thus the air volume increases and the humidity is high, can be lowered. That is, the effect of greatly improving the temperature gradient with respect to the direction of ventilation of the cooling air of the rotating electrical machine can be obtained.

  Next, a second embodiment of the present invention will be described with reference to FIG. That is, in the squirrel-cage induction motor that is the rotating electrical machine of the present embodiment, the stator core 1, the stator coil 2, the rotor core 3, the bearing 8, the ventilation path 16, and the introduction window 17 are described in the first embodiment. However, the partition plate 18 is provided in the wind intake window 10 of the stator frame 9, and the air from the cooling fan outside the machine is forcibly counteracted by the partition plate 18. It is set as the structure isolate | separated into the ventilation to the inside of a machine by the side of a drive (windward side), and the ventilation from the ventilation path 16 to the machine by the side of a drive side leeward. According to this embodiment, the effect of improving cooling and improving output can be obtained.

  Next, a third embodiment of the present invention will be described with reference to FIG. That is, the squirrel-cage induction motor, which is the rotating electrical machine of the present embodiment, has the stator iron core 1, the stator coil 2, the rotor iron core 3, the bearing 8, the partition plate 18, the ventilation path 16, and the introduction window 17 as the second. Although it is the same as the structure (FIG. 4) demonstrated in the Example, it is set as the structure which provided the partition plate 19 of the perimeter ring shape inside the leeward side machine of the stator frame 9. FIG. A gap L between the inner peripheral surface of the ring-shaped partition plate 19 and the end surface of the stator coil 2 is configured to be narrower than a distance L ′ between the end surface of the stator coil 2 and the air exhaust port 14 of the bracket 13. The airflow resistance of the cooling air introduced directly from the air passage 16 through the narrow gap portion and exhausted from the air outlet 14 of the bracket is increased, the air velocity on the surface of the stator coil 2 is increased, and the stator coil 2 is increased. An excellent cooling effect can be obtained by increasing the amount of cooling air flowing through the gap.

  Next, a fourth embodiment of the present invention will be described with reference to FIG. The squirrel-cage induction motor, which is a rotating electrical machine of the present embodiment, includes a stator core 1, a stator coil 2, a rotor core 3, a bearing 8, a partition plate 18, a ventilation path 16, and an introduction window 17 in the second embodiment. The wall surface on the outer peripheral side of the air exhaust port 14 of the bracket 13 is configured on the inner peripheral side of the electric motor from the center of the end curved surface of the stator coil 2. The gap Q between the end 2 and the end face of the bracket 13 is narrowed to be the same as the gap L shown in FIG. According to this embodiment, the resistance to ventilation in the gap Q is increased, the wind speed on the surface of the stator coil 2 is increased, and the amount of cooling air flowing through the gap in the stator coil 2 is increased, thereby achieving excellent cooling. An effect is obtained.

  Next, a fifth embodiment of the present invention will be described with reference to FIGS. 8 is a cross-sectional view taken along the line VIII-VIII in FIG. In the squirrel-cage induction motor of the present embodiment, the stator core 1, the stator coil 2, the rotor core 3, the bearing 8, the wind intake window 10, and the ventilation path 16 are the configurations described in the first embodiment (FIG. 1). In this embodiment, the stator core 1 in the leeward machine is provided with an arc-shaped wind regulating plate 20 when viewed from the axial direction of the motor. The air conditioning plate 20 diverts the cooling air that has been ventilated from the introduction window 17 of the ventilation path 16 of the stator frame 9 into the leeward side machine to the left and right. The diverted cooling air passes through the gap between the inner diameter surface of the stator frame 9 and the outer diameter surface of the air conditioning plate 20 and is guided to the lower part of the machine opposite to the introduction window 17. Due to this action, it is possible to suppress the temperature rise of the stator coil in the part farthest from the introduction window 17 where the cooling air with low temperature is difficult to hit and the temperature rise is large, and the temperature gradient of the leeward stator coil 2 is improved. be able to.

  Next, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 9 is a plan view seen from the direction of arrows IX-IX in FIG. 7 described in the fifth embodiment. The air conditioning plate 20 is configured such that the length “a” at the center is the longest and the length “a ′” at the end is shorter than “a”. The a portion having a large length dimension faces the position near the center of the introduction window 17, and the length dimension becomes shorter as the distance from the introduction window 17 increases. By configuring the air conditioning plate 20 in this way, the dimension b between the air conditioning plate 20 and the bracket 13 becomes wider as the length of the air conditioning plate 20 becomes shorter. The portion where the gap is narrow has a high resistance to cooling air, but the gap becomes wider toward the opposite side (lower side) of the introduction window 17 where the temperature of the stator coil 2 is higher on the leeward side. The temperature gradient of the leeward stator coil 2 can be improved.

The upper half longitudinal cross-sectional view of the rotary electric machine of 1st Example of this invention. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1. The temperature rise of the stator coil of a rotary electric machine is shown, (a) is a 1st Example of this invention, (b) is a graph which shows a conventional one. The upper half longitudinal cross-sectional view of the rotary electric machine of the 2nd Example of this invention. The upper half longitudinal cross-sectional view of the rotary electric machine of the 3rd Example of this invention. The upper half longitudinal cross-sectional view of the rotary electric machine of the 4th Example of this invention. The upper half longitudinal cross-sectional view of the rotary electric machine of the 5th Example of this invention. The cross-sectional view which follows the VIII-VIII line of FIG. The top view which shows the principal part of the rotary electric machine of the 6th Example of this invention, and follows the IX-IX line of FIG. The upper half longitudinal cross-sectional view of the conventional rotary electric machine. FIG. 11 is a cross-sectional view taken along line XI-XI in FIG. 10.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Stator iron core, 2 ... Stator coil, 3 ... Rotor iron core, 4 ... Shaft, 5 ... Rotor bar, 6 ... Short-circuit ring, 7 ... Rotor, 8 ... Bearing, 9 ... Stator frame, 10 ... Wind intake Window, 11 ... Gap, 12 ... Air hole, 13 ... Bracket, 14 ... Air outlet, 15 ... Air window, 16 ... Ventilation path, 17 ... Introducing window, 18 ... Partition plate, 19 ... Ring-shaped partition plate, 20 ... Air conditioning plate.

Claims (6)

  A stator core provided inside a stator frame having a cylindrical shape, a stator coil mounted on the stator core, and a bracket supported on an end of the stator frame and supported by the fixing A rotor that rotates with a predetermined gap between the inner peripheral surface of the core and a wind intake window that opens at one end of the stator frame and supplies cooling air into the machine; In the rotating electrical machine having a ventilation outlet formed on the bracket and for discharging cooling air to the outside of the machine, the other side of the stator frame is guided by cooling air from an air window provided outside the stator frame and opening to the wind intake window. A rotating electrical machine comprising a ventilation path for supplying cooling air into the machine from an introduction window opened at an end of the rotating machine.   The rotating electrical machine according to claim 1, wherein the wind window is formed by a partition plate provided in the wind intake window.   A ring-shaped partition plate attached to the inside of the other end of the stator frame, and the distance between the inner periphery of the ring-shaped partition plate and the end of the stator coil is the outer peripheral side of the exhaust port The rotating electrical machine according to claim 1, wherein the rotating electrical machine is formed to be smaller than a distance between an edge and an end of the stator coil.   The rotating electrical machine according to claim 1, wherein an outer peripheral side edge of the air exhaust port is formed on an inner peripheral side from a bending center of an end portion of the stator coil.   The rotating electrical machine according to claim 1, further comprising an arc-shaped rectifying plate that is attached to a side surface of the stator core and divides cooling air supplied from the introduction window into the machine in the circumferential direction. 6. The rotating electrical machine according to claim 5, wherein the current plate has a mountain shape with a long center and a short end.

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