Permanent magnet synchronous motor

Abstract

The purpose of the present invention is to provide a permanent magnet motor having improved cooling efficiency while having a small volume so as to be easy to install in a railcar bogie space. A permanent magnet synchronous motor comprises: a stator (100); a coil winding part (200) wound on the inside of the stator (100); a rotor (300) formed to rotate inside the stator (100); a front cover (400) installed in front of the stator (100); and a rear cover (500) installed behind the stator (100).　The present invention has the following effects.　First, a cooling water flow path is formed in an iron core piece of the stator itself rather than in a housing, and thus cooling efficiency is improved compared to prior art in which cooling is performed through a housing.　Second, since the housing is unnecessary, the motor is reduced in volume and can be easily installed in a railcar bogie having a small installation space.　Third, since the housing is unnecessary, the motor is lighter in weight.

Description

permanent magnet synchronous motor

[0001] The present invention relates to a permanent magnet synchronous motor used for traction of a high-speed railway vehicle, and more specifically, to a permanent magnet synchronous motor having a small volume and light weight while improving the cooling efficiency of heat generated inside the motor.

[0002] In general, a permanent magnet synchronous motor is an electric device that utilizes the rotational force of a rotating shaft by rotating the rotor through the interaction between the magnetic flux generated by the power applied to the coils wound on the stator and the magnetic flux by the permanent magnets of the rotor, and has a stator on which coils are wound and a rotor on which permanent magnets are arranged.

[0003] Permanent magnet synchronous motors have reduced rotor loss and increased efficiency compared to induction motors in which the rotor rotates by electromagnetic induction of the rotor, and therefore their application is being considered to improve the efficiency of high-speed railway vehicle drive systems.

[0004] Existing traction motors for railway vehicles are mainly open-type air-cooled induction motors. However, unlike induction motors, permanent magnet synchronous motors are prone to attracting foreign substances containing iron due to the magnetic force of the permanent magnets mounted on the rotor, which can lead to motor accidents. Therefore, the motor protection type must be a completely enclosed type (IP Grade 54) that prevents external cooling air from entering the motor.

[0005] In general, since high heat is generated in the stator and rotor during operation, open-air-cooled induction motors directly cool the heat of the windings with cooling air, while closed-air motors cool the motor by transferring the heat generated in the stator windings to the motor housing via the stator core and using cooling air to cool the motor housing.

[0006] Accordingly, the closed type has the disadvantage of lower cooling efficiency compared to the open type that allows external cooling air to enter the inside of the motor.

[0007] When applying a permanent magnet synchronous motor, the decrease in cooling efficiency due to the adoption of a completely enclosed type must be resolved.

[0008] To compensate for the decline in cooling efficiency of electric motors, general electric motors are designed to increase thermal capacity by increasing volume. However, in the case of railway vehicles, the bogie space for installing electric motors is limited, so there is a limit to increasing volume.

[0009] To improve cooling efficiency while maintaining the motor protection type as a fully enclosed type, water cooling is applied as the motor cooling method.

[0010] However, in the conventional water-cooled motor, the cooling function is performed by using a water jacket method in which a cooling water path is installed in the housing.

[0011] Therefore, there is a problem that the thickness of the housing increases to form a cooling water passage inside the housing, making it unsuitable for installation in a narrow railway vehicle bogie space.

[0012] Additionally, there is a disadvantage in terms of cooling efficiency due to the gap between the housing and the stator.

[0013] [Prior art literature

[0014] Korean Patent No. 10-1257439 (registration date: April 17, 2013)

[0015] The present invention aims to provide a permanent magnet motor having improved cooling efficiency and a small volume for easy installation in a railway vehicle bogie space.

[0016] In order to solve the above-mentioned problem, the present invention is a permanent magnet synchronous motor comprising a stator (100), a coil winding (200) wound inside the stator (100), a rotor (300) formed to rotate inside the stator (100), a front cover (400) installed in front of the stator (100), and a rear cover (500) installed in the rear of the stator (100).

[0017] In the permanent magnet synchronous motor of the present invention, the stator (100) comprises a core portion (110),

[0018] It is composed of a pressure support part (120) installed at both ends of the core part (110), a fixing part (130) installed at the end of the pressure support part (120), and a cover part (140) installed on the outside of the core part (111).

[0019] In the permanent magnet synchronous motor of the present invention, the core portion (110) is formed by stacking a plurality of stator core pieces (111), and each stator core piece (111) has an annular portion (111a) formed therein so that a rotor (200) is installed, and a plurality of open grooves (111b) having open ends are formed in a circumferential direction to form a winding portion (300) on the outside of the annular portion (111a), and a plurality of cooling water channels (111c) for cooling water to flow are formed in a circumferential direction on the outside of the open grooves (111b).

[0020] In the permanent magnet synchronous motor of the present invention, a protrusion (111d) is formed upward from the inside of the cooling water passage (111c) at the lower portion of the cooling water passage (111c).

[0021] In the permanent magnet synchronous motor of the present invention, the pressurizing support member (120) has an annular portion (121) formed so that a rotor (200) is installed therein, a first open groove (122) having a plurality of openings formed in a circumferential direction and having an open end for pressing a winding portion (300) to the outside of the annular portion (121), and a second open groove (123) having a plurality of openings formed in a circumferential direction for pressing the cooling water passage (111c) to the outside of the first open groove (122).

[0022] In the permanent magnet synchronous motor of the present invention, the fixed part (130) is provided with an annular part (131) in which a rotor (200) is installed, a plurality of cooling water flow parts (132) formed in an arc shape so as to be formed in a circumferential direction on the outside of the annular part (131) and communicate with the cooling water passages (111c) of each core piece (111), and a support part (133) formed on the outside of the annular part (131) for fixing to a railway vehicle bogie.

[0023] In the permanent magnet synchronous motor of the present invention, the cover part (140) is formed to partially cover the laminated stator core pieces (111).

[0024] In the permanent magnet synchronous motor of the present invention, the front cover (400) is fixed to the fixed part (130), and has a cooling water inlet chamber (410) formed in an annular shape on the inner circumference, and a cooling water inlet port (420) formed as a through hole for cooling water to be introduced from the outside of the cooling water inlet chamber (410), and the cooling water inlet port (420) is formed to communicate with the cooling water flow portion (132) of the pressurizing portion (130), the first open groove (122) of the pressurizing support portion (120), and the cooling water path (111c) of the stator core piece (111) so that the cooling water can be introduced and flow.

[0025] In the permanent magnet synchronous motor of the present invention, the rear cover (500) is fixed to the fixed part (130), and has a cooling water discharge chamber (510) formed in an annular shape on the inner circumference, and a cooling water discharge port (520) formed by forming a through hole so that cooling water flows out from the outside of the cooling water discharge chamber (510), and the cooling water discharge port (520) is formed to communicate with the cooling water flow part (132) of the pressurizing part (130), the first open groove (122) of the pressurizing support part (120), and the cooling water path (111c) of the stator core piece (111) so that the cooling water can flow out.

[0026] In the present invention, a cooling water passage (111c) is formed in the stator core (111) itself, which provides the following advantages.

[0027] First, since the cooling water path is formed in the core of the stator itself rather than in the housing, it has the advantage of improving the cooling efficiency of the motor compared to the conventional technology of cooling through the housing.

[0028] Secondly, since the housing is unnecessary, the volume is reduced, making it easy to install on a railway vehicle bogie with a narrow installation space.

[0029] Thirdly, since the housing is unnecessary, the weight of the motor itself becomes lighter, which has the advantage of reducing weight.

[0030] Figure 1 is a perspective view showing an electric motor of one embodiment of the present invention.

[0031] Figure 2 is an exploded perspective view of an electric motor of one embodiment of the present invention.

[0032] Figure 3 is an exploded perspective view of a fixing part in one embodiment of the present invention.

[0033] Figure 4 is a front view of a stator core piece in one embodiment of the present invention.

[0034] Figure 5 is a front view of a pressurized fixing part in one embodiment of the present invention.

[0035] Fig. 6 is a cross-sectional view of a motor according to one embodiment of the present invention.

[0036] The present invention is susceptible to various modifications and embodiments. Specific embodiments are illustrated in the drawings and detailed descriptions of specific embodiments for carrying out the invention are provided. However, this is not intended to limit the present invention to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention. Throughout the description of each drawing, similar reference numerals have been used to designate similar components.

[0037] Terms such as first, second, A, and B may be used to describe various components, but these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component. The term "and / or" includes a combination of multiple related items described herein or any of multiple related items described herein.

[0038] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0039] The terminology used in this application is only used to describe specific embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, it should be understood that the terms "comprise" or "have" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0040] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0041] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0042] Fig. 1 is a perspective view illustrating an electric motor according to one embodiment of the present invention. Fig. 2 is an exploded perspective view of an electric motor according to one embodiment of the present invention. Fig. 3 is an exploded perspective view of a fixing part according to one embodiment of the present invention.

[0043] A permanent magnet synchronous motor of one embodiment of the present invention is composed of a stator (100), a coil winding (200) wound inside the stator (100), a rotor (300) formed to rotate inside the stator (100), a front cover (400) installed in front of the stator (100), and a rear cover (500) installed in the rear of the stator (100).

[0044]

[0045] The stator (100) is composed of a core part (110), a pressure support part (120) installed at both ends of the core part (110), a fixing part (130) installed at the end of the pressure support part (120), and a cover part (140) installed on the outside of the core part (111).

[0046]

[0047] Figure 4 is a front view of a stator core piece in one embodiment of the present invention.

[0048] The core portion (110) is formed by stacking a plurality of stator core pieces (111).

[0049] Each stator core (111) is formed with an annular portion (111a) so that a rotor (200) is installed inside, and a plurality of open grooves (111b) are formed in the circumferential direction with the ends open to form a winding portion (300) on the outside of the annular portion (111a).

[0050] Meanwhile, a plurality of cooling water passages (111c) are formed in the circumferential direction on the outside of the open groove (111b) in the stator core (111) for cooling water to flow.

[0051] A protrusion (111d) is formed upward from the inside of the coolant channel (111c) at the lower part of the coolant channel (111c) so as to increase the surface area in contact with the coolant.

[0052]

[0053] Figure 5 is a front view of a pressurized fixing part in one embodiment of the present invention.

[0054] The pressurized support member (120) is formed in a shape similar to the core piece (111) to pressurize a plurality of stator core pieces.

[0055] That is, each pressurized support member (120) is formed with an annular portion (121) so that a rotor (200) is installed inside, and a plurality of first open grooves (122) are formed in the circumferential direction, the ends of which are open to pressurize the winding member (300) to the outside of the annular portion (121).

[0056] Meanwhile, in each pressurized support member (120), a plurality of second open grooves (123) are formed in the circumferential direction on the outside of the first open groove (122) to pressurize the cooling water passage (111c).

[0057]

[0058]

[0059] The fixed part (130) has an annular part (131) in which a rotor (200) is installed, and a plurality of cooling water flow parts (132) are formed in an arc shape on the outer side of the annular part (131) in a circumferential direction and communicate with the cooling water passages (111c) of each iron core piece (111).

[0060] A support member (133) for fixing to a railway vehicle bogie is formed on the outside of the fixed member (130).

[0061]

[0062] Meanwhile, on the outside of the core section (110), a cover (140) is fixed to a plurality of stator core pieces (111) laminated by welding or the like, thereby fixing the laminated stator core pieces (111).

[0063]

[0064] In the present invention, the cover part (140) is formed not to completely cover the laminated stator core pieces (111), but to partially cover them, thereby minimizing volume and weight.

[0065]

[0066] The rotor (300) is composed of a rotation axis (310) and a magnet portion (320) formed on the outer periphery of the rotation axis (310).

[0067] The present invention relates to a permanent magnet synchronous motor, in which permanent magnets are installed instead of coils around a rotating shaft.

[0068]

[0069]

[0070] The front cover (400) is fixed to the fixed part (130), and a cooling water inlet chamber (410) is formed in an annular shape.

[0071] In the cooling water inlet chamber (410), a cooling water inlet port (420) is formed by forming a through hole around the periphery to allow cooling water to flow in.

[0072] The cooling water inlet (420) is formed to allow the cooling water to flow in through the cooling water flow portion (132) of the pressurized portion (130), the first open groove (122) of the pressurized support portion (120), and the cooling water path (111c) of the stator core piece (111).

[0073]

[0074] The rear cover (500) is fixed to the fixed part (130), and a cooling water discharge chamber (510) is formed in an annular shape.

[0075] In the cooling water discharge chamber (510), a cooling water discharge port (520) is formed by forming a through hole around the periphery to allow cooling water to discharge.

[0076] The coolant outlet (520) is formed to allow the coolant to flow out through the coolant flow portion (132) of the pressurized portion (130), the first open groove (122) of the pressurized support portion (120), and the coolant passage (111c) of the stator core piece (111).

[0077] Fig. 6 is a cross-sectional view of a motor according to one embodiment of the present invention.

[0078] Next, the operation of the present invention will be described.

[0079] In the present invention, the coolant introduced through the coolant inlet (410) formed in the front cover (400) flows through the coolant inlet chamber (410) to the coolant flow portion (132) of the pressurized portion (130), the first open groove (122) of the pressurized support portion (120), and the coolant passage (111c) of the stator core piece (111).

[0080] When the coolant flows through the coolant path (111c) of the stator core (111) formed by stacking multiple pieces, it cools the stator (100) and thus cools the entire motor.

[0081] In the present invention, a cooling water passage (111c) is formed in the stator core (111) itself, which provides the following advantages.

[0082] First, since the cooling water path is formed in the core of the stator itself rather than in the housing, it has the advantage of improving the cooling efficiency of cooling the motor compared to the conventional technology of cooling through the housing.

[0083] Secondly, since the housing is unnecessary, the volume is reduced, making it easy to install on a railway vehicle bogie with a narrow installation space.

[0084] Thirdly, since the housing is unnecessary, the weight of the motor itself becomes lighter, which has the advantage of reducing weight.

[0085] Meanwhile, the cooling water that has performed a cooling action by flowing through the cooling water path (111c) of the stator core (111) flows to the first open groove (122) of the pressurized support (120), the cooling water flow portion (132) of the pressurized portion (130), and the cooling water outlet chamber (510) of the rear cover (500) and is discharged through the cooling water outlet (520).

[0086] Although a preferred embodiment of the present invention has been described above, it is obvious to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or scope thereof, in addition to the described embodiments.

[0087] The present invention provides a permanent magnet motor having improved cooling efficiency and a small volume for easy installation in a railway vehicle bogie space, thereby enabling high-efficiency operation while taking up less space in a railway vehicle.

Claims

1. As a permanent magnet synchronous motor, a stator (100), a coil winding part (200) wound inside the stator (100), a rotor (300) formed to rotate inside the stator (100), a front cover (400) installed in front of the stator (100), a rear cover (500) installed behind the stator (100), a permanent magnet synchronous motor composed of these.

2. According to claim 1, the stator (100) is, a core part (110), a pressing support part (120) installed at both ends of the core part (110), a fixing part (130) installed at the end of the pressing support part (120), a cover part (140) installed outside the core part (111), a permanent magnet synchronous motor composed of these.

3. According to claim 2, the core part (110) is formed by laminating a plurality of stator core pieces (111), each of the stator core pieces (111) is, an annular part (111a) is formed so that a rotor (200) is installed inside, a plurality of open grooves (111b) with open ends are formed in the circumferential direction to form a winding part (300) outside the annular part (111a), a plurality of cooling water channels (111c) for the cooling water to flow are formed in the circumferential direction outside the open grooves (111b), a permanent magnet synchronous motor.

4. According to claim 3, a protruding part (111d) protruding upward is formed inside the cooling water channel (111c) at the lower part of the cooling water channel (111c), a permanent magnet synchronous motor..

5. According to claim 4, the pressing support part (120) is, an annular part (121) formed so that a rotor (200) is installed inside, a first open groove (122) with an open end and a plurality of them formed in the circumferential direction to press the winding part (300) outside the annular part (121), a second open groove (123) with a plurality of them formed in the circumferential direction to press the cooling water channel (111c) is provided outside the first open groove (122), a permanent magnet synchronous motor.

6. According to claim 5, the fixing part (130) is, an annular part (131) in which a rotor (200) is installed inside, A plurality of cooling water flow portions (132) formed in a circumferential direction on the outside of the annular portion (131) and formed in an arc shape so as to communicate with the cooling water flow paths (111c) of the respective core pieces (111), A permanent magnet synchronous motor having a support portion (133) formed on the outside of the annular portion (131) for fixing to a railroad vehicle bogie.

7. The permanent magnet synchronous motor according to claim 6, The cover portion (140) is formed to partially cover the laminated stator core pieces (111) and is fixed.

8. The permanent magnet synchronous motor according to claim 7, The front cover (400) is fixed to the fixing portion (130), A cooling water inlet chamber (410) formed in an annular shape on the inner circumference, A cooling water inlet (420) formed by forming a through hole for cooling water to flow in from the outside of the cooling water inlet chamber (410), The cooling water inlet (420) communicates with the cooling water flow portion (132) of the pressurizing portion (130), the first opening groove (122) of the pressurizing support portion (120), and the cooling water flow path (111c) of the stator core piece (111), and is formed so that cooling water can flow in.

9. The permanent magnet synchronous motor according to claim 8, The rear cover (500) is fixed to the fixing portion (130), A cooling water outlet chamber (510) formed in an annular shape on the inner circumference, A cooling water outlet (520) formed by forming a through hole for cooling water to flow out from the outside of the cooling water outlet chamber (510), The cooling water outlet (520) communicates with the cooling water flow portion (132) of the pressurizing portion (130), the first opening groove (122) of the pressurizing support portion (120), and the cooling water flow path (111c) of the stator core piece (111), and is formed so that cooling water can flow out.

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