JP2016054644A - Embedded permanent magnet type rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an embedded permanent magnet type rotary electric machine in which cooling effects of permanent magnets can be enhanced by cooling directly the permanent magnets with a cooling medium.SOLUTION: The embedded permanent magnet type rotary electric machine comprises: a stator 10 having an armature winding 15; a rotator 20 that has rotor iron cores 21, which is constituted by laminating magnetic material plates cylindrically and provided rotatably inside the stator 10, and has a plurality of magnet storage holes 25 penetrating through in a laminating direction of the magnetic material plates of the rotor iron core 21 formed at predetermined positions in a circumferential direction; and a plurality of permanent magnets 23 stored in the plurality of magnet storage holes 25 respectively. In each permanent magnet 23, a part corresponding to outside in a radial direction of the rotor iron core 21 is fixed to the rotor iron core 21 in the magnet storage hole 25. A refrigerant passage 27 is formed in a shaft direction of the rotor iron core 21, between the rotor iron core 21 and the magnet, in a part corresponding to the inside in the radial direction of the rotor iron core 21. At an exposed part 21a of the rotor iron core 21 in the refrigerant passage 27, a plurality of protruding parts 28 are arranged, which are caused by shear droop 29 generated during press processing of the magnetic material plates, in a direction orthogonal to a flowing direction of a cooling medium.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a permanent magnet embedded type rotating electric machine in which a permanent magnet is embedded in a rotor.

Conventionally, there is known a permanent magnet embedded type rotating electric machine including a rotor in which a permanent magnet is embedded in a rotor core made of laminated magnetic steel sheets and a stator having an armature winding around the rotor. It has been.
In such a permanent magnet embedded type rotating electrical machine, as a method of cooling the permanent magnet, in addition to a method of dissipating heat by applying cooling oil to the rotor surface from the outside, a rotation in which magnetic material plates are laminated as in Patent Document 1 There is a method of providing a coolant channel in the core.

JP 2011-223717

  However, the conventional permanent magnet embedded type rotating electric machine has a problem that the cooling effect is low because the cooling medium is not directly applied to the permanent magnet, and it is difficult to increase the output of the electric motor used in the electric power steering apparatus or the like.

An object of the present invention is to provide an embedded permanent magnet type rotating electrical machine that can improve the cooling effect of a permanent magnet by directly cooling the permanent magnet with a cooling medium. To do.

  The permanent magnet motor of the present invention is configured by laminating a stator having an armature winding and a magnetic material plate in a cylindrical shape, and has a rotor core provided rotatably inside the stator, A rotor in which a plurality of magnet housing holes penetrating in the stacking direction of the magnetic material plates of the rotor core are formed at predetermined positions in the circumferential direction, and a plurality of permanent magnets respectively housed in the plurality of magnet housing holes Each permanent magnet is fixed to the rotor core at a portion corresponding to the radially outer side of the rotor core in the magnet housing hole, and the rotation at a portion corresponding to the radially inner side of the rotor core. The refrigerant core is arranged so as to form a refrigerant passage through which the refrigerant passes in the axial direction of the rotor core, and the exposed portion of the rotor core in the refrigerant passage is orthogonal to the flow direction of the refrigerant. Direction of the magnetic material plate Installing a plurality of convex portions by punching sag during the scan process.

  According to the permanent magnet motor of the present invention, the refrigerant passage is formed under the permanent magnet, and the refrigerant is caused to collide with the convex portion of the refrigerant passage, thereby transferring the refrigerant flow from laminar flow to turbulent flow and in the vicinity of the permanent magnet. Since the temperature boundary layer can be effectively prevented, the cooling effect of the permanent magnet can be enhanced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side cross-sectional view of a permanent magnet embedded rotary electric machine showing Embodiment 1 of the present invention. FIG. 3 is a plan view showing the rotor in the first embodiment. It is a principal part enlarged view which shows the permanent magnet periphery part of FIG. FIG. 4 is a sectional view taken along line IV-IV in FIG. 3. FIG. 5 is a sectional view taken along line VV in FIG. 3. It is principal part sectional drawing which shows Embodiment 2 of this invention. It is principal part sectional drawing which shows Embodiment 3 of this invention.

Embodiment 1 FIG.
FIG. 1 is a side sectional view showing a permanent magnet embedded electric motor according to Embodiment 1 of the present invention, and shows an example in which a plate-like permanent magnet is used and is configured with 16 poles and 48 slots.
The stator 10 includes U1, U2, W1, W2, V1, V2, U1, U2, W1, W2, V1, and V2 as armature windings of distributed windings accommodated in the core core 12, stator teeth 13 and slots 14, and slots 14. An armature winding 15 is accommodated.
U1, U2, W1, W2, V1, and V2 indicate that there are two sets of three-phase armature windings 15; the first U-phase winding is U1, the second U-phase winding is U2, The first V-phase winding is V1, the second V-phase winding is V2, the first W-phase winding is W1, and the second W-phase winding is W2.
U1, V1, and W1 constitute the first armature winding and are connected to the first inverter, and U2, V2, and W2 constitute the second armature winding and are connected to the second inverter. .

  On the other hand, the rotor 20 has a rotor core 21 rotatably provided inside the stator 10, a rotating shaft 22 inserted in the center of the rotor core 21, and a flat plate shape embedded in the rotor core 21. The permanent magnet 23 is provided.

FIG. 2 is a plan view showing the rotor 20 in FIG. 1, which has a rotor core 21 in which magnetic material plates are laminated in a cylindrical shape, and a shaft insertion hole 24 into which the rotation shaft 22 is inserted at the center thereof. There are provided 16 magnet housing holes 25 at equal intervals in the radially peripheral portion for housing the plate-like permanent magnets 23, and the coolant is provided around the shaft insertion hole 24 on the inner peripheral side of the permanent magnets 23. Eight through holes 26 through which the cooling oil passes are provided at equal intervals.
Note that N and S in FIG. 2 represent the polarity of the permanent magnet 23. That is, in FIG. 1, magnets having different polarities are arranged alternately.
Moreover, the magnetic material plate used for the rotor core 21 is a functional material that improves the characteristics (magnetism) of the iron that reaches the magnet and efficiently exchanges the energy of magnetism.

FIG. 3 is an enlarged view of a portion A in FIG. 2, showing the structure of the peripheral portion of the permanent magnet accommodated in the magnet accommodation hole 25, and a coolant that passes cooling oil between the magnet accommodation hole 25 and the permanent magnet 23. A passage 27 is formed.
The refrigerant passage 27 is formed around the permanent magnet 23 so as to function as a gap through which cooling oil passes in the axial direction of the rotor core 21, and in a portion corresponding to the radially inner side of the rotor core 21 of the permanent magnet 23. The rotor core 21 is formed in a gap with the magnet housing hole 25.
That is, the permanent magnet 23 is fixed to the rotor core 21 by a fixing resin layer at a portion corresponding to the radially outer long side portion of the rotor core 21 in the magnet housing hole 25, and the radial direction of the rotor core 21 is fixed. The portion corresponding to the inner long side portion is arranged so as to form a gap that becomes the refrigerant passage 27 without providing the fixing resin layer.

As shown in FIGS. 4 and 5, in the refrigerant passage 27 below the permanent magnet, a plurality of convex portions 28 are adjacent to the exposed portion 21 a of the rotor core 21 in a direction perpendicular to the direction in which the cooling oil flows. It is arranged in a zigzag so as not to overlap the part.
By arranging the plurality of convex portions 28 in the refrigerant passage 27 below the permanent magnet in this way, the transition from laminar flow to turbulent flow when the cooling oil collides with the convex portion 28, the temperature boundary layer near the permanent magnet is reduced. It can be effectively prevented.

In FIG. 4, a plurality of convex portions 28 are installed at equal intervals in the axial direction on the exposed portion 21 a of the rotor core 21 that forms the refrigerant passage 27 below the permanent magnet, and adjacent convex portions do not overlap each other. Due to the arrangement, the cooling oil easily collides with the convex portion 28, and when the cooling oil collides with the convex portion 28, the transition from laminar flow to turbulent flow effectively prevents the temperature boundary layer near the permanent magnet. It is possible to increase the cooling effect of the permanent magnet.

  Although not shown, the cooling oil is supplied to the refrigerant passage 27 from a hollow hole provided at the center of the rotating shaft 22 by a scattering prevention plate provided at one end of the rotor 20. This is done via the refrigerant passage.

  As described above, the embedded permanent magnet rotating electric machine of the present invention is configured by laminating the stator 10 having the armature winding 15 and the magnetic material plate in a cylindrical shape, and is rotatable inside the stator 10. A rotor core 21 provided on the rotor, and a plurality of magnet housing holes 25 penetrating in the laminating direction of the magnetic material plates of the rotor core 21 at a predetermined position in the circumferential direction; A plurality of permanent magnets 23 respectively housed in the magnet housing holes 25 are provided, and each permanent magnet 23 is fixed to the rotor core 21 at a portion corresponding to the outer side in the radial direction of the rotor core 21 in the magnet housing hole 25. A refrigerant passage 27 through which cooling oil passes in the axial direction of the rotor core 21 is formed between the rotor core 21 and the rotor core 21 at a portion corresponding to the radially inner side of the core iron 21. Exposed portion 21 of rotor core 21 A plurality of projections 28 are installed in a direction orthogonal to the flow direction of the cooling oil, and the permanent magnet 23 can be directly cooled by the cooling oil, and the rotor core is provided in the refrigerant passage 27 below the permanent magnet. Since the plurality of convex portions 28 are installed in the exposed portion 21a of the 21 in a direction orthogonal to the direction in which the cooling oil flows, the flow of the cooling oil passing through the refrigerant passage 27 is disturbed from the laminar flow when colliding with the convex portion 28. By making the transition to the flow, the temperature boundary layer near the permanent magnet can be effectively prevented, and the cooling effect of the permanent magnet 23 can be further enhanced.

Embodiment 2. FIG.
In the first embodiment, the case where the plurality of convex portions 28 are installed in the direction orthogonal to the direction in which the cooling oil flows in the exposed portion 21a of the rotor core 21 in the refrigerant passage 27 below the permanent magnet has been described. In the exposed portion 21a of the rotor core 21 forming the refrigerant passage 27, the shape of the end of the magnetic material plate constituting the rotor core 21 is shaped into a mountain shape, and the rotor core itself has a convex portion. 28 is formed.
In this way, the rotor core itself can form the convex portion 28 in the refrigerant passage 27, and the flow of the cooling oil passing through the refrigerant passage 27 collides with the convex portion 28 as in the first embodiment. In this case, transition from laminar flow to turbulent flow can prevent the temperature boundary layer in the vicinity of the permanent magnet, and the cooling effect of the permanent magnet 23 can be further enhanced.

Embodiment 3 FIG.
In the second embodiment, the end portion of the magnetic material plate constituting the rotor core 21 is shaped to form the convex portion 28. However, as shown in FIG. The part sag 29 is disposed on the exposed portion 21 a of the rotor core 21 that forms the refrigerant passage 27 and is used as a convex portion.
In this way, the convex portion 28 can be formed in the refrigerant passage 27 using the pressed magnetic material plate as it is, and the flow of the cooling oil passing through the refrigerant passage 27 as in the first and second embodiments. Can be made to transition from laminar flow to turbulent flow when colliding with the sag 29, thereby preventing the temperature boundary layer near the permanent magnet and further enhancing the cooling effect of the permanent magnet 23.

It should be noted that within the scope of the present invention, the embodiments can be freely combined, or the embodiments can be appropriately modified or omitted.

10 stator, 11 stator core, 12 core back, 13 teeth, 14 slots,
15 armature winding,
20 Rotor, 21 Rotor core, 21a Exposed portion, 22 Rotating shaft, 23 Permanent magnet, 24 Shaft insertion hole, 25 Magnet housing hole, 26 Through hole, 27 Refrigerant passage, 28 Protruding portion, 29 Pull-out

Claims (3)

A stator having armature windings;
A magnet housing hole configured by laminating magnetic material plates in a cylindrical shape, having a rotor core rotatably provided inside the stator, and penetrating in the stacking direction of the magnetic material plates of the rotor core A plurality of rotors formed at predetermined positions in the circumferential direction;
A plurality of permanent magnets respectively housed in the plurality of magnet housing holes,
Each of the permanent magnets is fixed to the rotor core at a portion corresponding to the radially outer side of the rotor core in the magnet housing hole, and the rotor core at a portion corresponding to the radially inner side of the rotor core. And is arranged so as to form a refrigerant passage through which the refrigerant passes in the axial direction of the rotor core,
A plurality of convex portions are installed in the exposed portion of the rotor core in the refrigerant passage in a direction perpendicular to the flow direction of the refrigerant by punching when the magnetic material plate is pressed. Built-in rotary electric machine. 2. The embedded permanent magnet rotating electric machine according to claim 1, wherein the plurality of convex portions are installed so that the refrigerant flows from a burring side of the punching sagging. The permanent magnet has a flat plate shape, and a portion corresponding to the radially outer long side portion of the rotor core in the magnet housing hole is fixed to the rotor core by a fixing resin layer, and the diameter of the rotor core is The embedded permanent magnet type rotating electrical machine according to claim 1 or 2, wherein a portion corresponding to the inner side long side portion is disposed so as to form a gap serving as the refrigerant passage.

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