JP2002191155A - Rotating electric machine - Google Patents

Abstract

(57) [Summary] [PROBLEMS] By efficiently conducting heat transfer between a coil end of a stator winding and a frame, the stator winding can be efficiently cooled, and the output can be improved and the size and weight can be reduced. And a method for manufacturing the same. A rotor provided with a permanent magnet, a stator core disposed around the rotor and fitted inside a frame, and a stator winding wound around the stator core. In the rotary electric machine G provided with the wire 3, ring-shaped or split ring-shaped heat conductors 11, 11 A are inserted between the coil end 3 e of the stator winding 3 and the frame 1, and the heat conductor 11 , 11A, the coil end 3e, and the frame 1
And the thermosetting resin 12 is filled and fixed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating electric machine such as a generator or a motor having a rotor having a permanent magnet attached to a rotating shaft, and to efficiently conduct heat generated in a stator winding to a frame. The present invention relates to a rotating electric machine having good cooling performance.

[0002]

2. Description of the Related Art Conventionally, a rotating electric machine such as a generator or an electric motor having a rotor with a permanent magnet attached to a rotating shaft can obtain a high output with a simple structure, and is therefore often used for an engine or industrial equipment. In order to cope with restrictions such as control performance and mounting space, higher output, smaller size and lighter weight, and hermetically sealed structure have been advanced.

[0003] However, when such a high output, a small size and light weight, and a hermetically sealed structure are performed, the amount of heat generated per unit volume increases, and the temperature rise increases.

That is, when the power generation output and the output torque increase, the amount of heat generated in the stator winding increases, and the stator (stator) temperature increases, even if the efficiency is the same. Then, heat moves from the stator side to the rotor (rotor) side by radiation or the like, and the temperature of the rotor increases. Since the magnetic force of the permanent magnet on the rotor side decreases due to the temperature increase, the output also decreases accordingly.

The magnetic force of the permanent magnet, which causes a decrease in output, is reduced by as much as 1% at a temperature rise of 10 ° C., for example, and therefore, when the temperature of the rotor rises to about 120 ° C., the room temperature (20 ° C.) It will be 10% lower than the time.

Therefore, it is necessary to efficiently transfer the heat generated in the stator windings to the frame for cooling. The frame is provided with cooling fins or a liquid cooling jacket through which cooling water or cooling oil flows. Or

In a conventional rotating electric machine shown in FIG. 5, a stator core 2 is fitted and fixed to a frame 1, and a stator winding 3 is wound around a slot portion of the stator core 2. A rotor 7 is provided around the rotating shaft 6, and the rotating shaft 6 is rotatably supported by bearings 5 provided on brackets 4 at both ends of the frame 1. A resin 10 having high thermal conductivity is filled and fixed between the coil end 3 e of the stator winding 3 and the inner peripheral surface of the frame 1.

A pulley P is mounted on one end of the rotating shaft 6 and is connected to an engine or the like via a belt V so as to be capable of transmitting power.

In this configuration, part of the heat generated in the stator winding 3 is transmitted from the coil end 3e to the resin 1 having high thermal conductivity.
0, the heat is transferred to the frame 1 and radiated from the cooling fins 9 of the frame 1, and the rest is transferred to the frame 1 via the stator core 2 and cooled in the slots provided in the stator core 2. Heat is radiated from the fins 9.

Since the rotating electric machine shown in FIG. 5 is an air-cooled type, heat is radiated from the cooling fins 9.
A liquid cooling jacket is provided in the frame 1 and is cooled by water or oil flowing in the liquid cooling jacket.

[0011]

However, when a resin having high thermal conductivity is provided between the frame and the coil end as in the rotating electric machine shown in FIG. Epoxy resin of thermosetting resin is used for simplicity. However, although it is a resin with high thermal conductivity, the thermal conductivity of epoxy resin itself is not so high, so heat transfer efficiency is poor and heat conduction is insufficient, cooling is not enough. There is a problem of inefficiency.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to efficiently transfer heat between a coil end of a stator winding and a frame. An object of the present invention is to provide a rotating electric machine such as a generator or an electric motor capable of efficiently cooling a stator winding and improving output and reducing size and weight.

[0013]

A rotating electric machine such as a generator or an electric motor for achieving the above object is provided with a rotor having a permanent magnet, a rotor disposed around the rotor, and an inner side of a frame. In a rotating electric machine including a fitted stator core and a stator winding wound around the stator core, a ring-shaped or split ring-shaped or coil is provided between a coil end of the stator winding and the frame. A heat conductor in a shape of is inserted, and a fixing agent is filled between the heat conductor, the coil end, and the frame to be fixed.

By inserting a high thermal conductor between the coil end and the frame (housing), a high thermal conductivity can be obtained, so that the heat generated in the stator winding is transferred from the coil end to the coil end. Heat can be transferred to the frame via the heat conductor, and cooling can be performed efficiently. Thus, the temperature of the permanent magnet of the rotor can be prevented from rising, and the magnetic force of the permanent magnet can be maintained.

In the above rotating electric machine, the heat conductor is formed by laminating thin metal plates.

[0016] With the configuration in which the heat conductor is formed of a metal having a remarkably high heat conductivity such as aluminum or copper, heat can be efficiently transferred from the coil end to the frame. In addition, by using a metal thin plate that can be easily formed by pressing or the like, a ring shape, a split ring shape, or a coil shape can be easily formed, and this heat conductor can be formed at low cost.

Further, by forming this metal by lamination of thin plates, eddy current induced by current flowing through the coil end can be suppressed, and eddy current loss generated by this metal can be reduced.

Alternatively, in the above rotating electric machine, the heat conductor is formed of ceramic.

In addition to aluminum oxide (alumina: Al ₂ O ₃ ), beryllium oxide (BeO), magnesium oxide (magnesia: Mg)
O), titanium dioxide (TiO ₂ ), aluminum nitride (AlN), silicon dioxide (silica: SiO ₂ ), trisilicon tetranitride (Si ₃ N ₄ ), boron nitride (BN), and the like.

By forming the thermal conductor from a material having high thermal conductivity of a ceramic such as aluminum oxide (alumina) and a high insulating property, a high insulating property can be secured between the coil end and the frame.

Further, in the rotating electric machine, a silicone resin is employed as the fixing agent. Alternatively, a thermosetting resin such as an epoxy resin (EP), a phenol resin (PF), a polyimide (PI), an unsaturated polyester (UP), and a vinyl ester resin (VE) can be employed. It is preferable to employ epoxy resin (EP), phenol resin (PF), or polyimide (PI).

In other words, by selecting these generally available materials, it is possible to easily secure good heat conduction characteristics, electrical insulation characteristics, and easiness of molding, and at the same time, to firmly bond with silicone resin or epoxy resin. Power can be obtained, and a cooling structure or the like for the coil end portion of the rotating electric machine can be configured by a simple operation at a low cost.

[0023]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a rotating electric machine according to an embodiment of the present invention. Here, a permanent magnet type generator will be described as an example.

FIG. 1 is a side sectional view showing a configuration of a permanent magnet generator according to an embodiment of the present invention, FIG. 2 is a perspective view of a heat conductor, and FIG. FIG. 4 is a cross-sectional view showing the configuration of the stator, and FIG. 4 is an enlarged cross-sectional view of a stator winding portion.

As shown in FIGS. 1 to 4, the generator G includes a bearing 5 provided on a bracket 4 fixed to a frame (housing) 1 and a rotating shaft 6 on which a rotor 7 is disposed is rotatable. The stator 7 is wound around the outer periphery of the rotor 7 through the stator core 2 fixed to the frame 1 side and the slot 23 between the teeth 22 of the stator core 2. The secondary winding 3 is provided.

A pulley P is attached to one end of the rotating shaft 6 in the same manner as the conventional one, and is connected to an engine or the like via a belt V so as to be able to transmit.

As shown in FIG. 3, the rotor 7 has a permanent magnet 71 fixed to the rotating shaft 6, and a permanent magnet 7 is provided on the outer periphery of a back yoke 72 provided integrally with the rotating shaft 6.
1 are arranged and formed. The permanent magnet 71 is formed by laminating magnet pieces that have been magnetized for each single pole and assembling them into multiple poles in order to secure the required output. The lamination length is the same as that of the back yoke 72. , Both ends of which are sandwiched by a pair of plates having a disc spring effect and fixed to the back yoke 72.

Further, in order to prevent the permanent magnet 71 from being destroyed by centrifugal force during rotation, SUS or CFRP (carbon fiber reinforced plastic) is used over the entire outer periphery of the permanent magnet 71.
A sleeve 73 made of a non-magnetic material is provided.

On the other hand, as shown in FIGS. 1, 3 and 4, the fixed iron core 2 has a ring portion 21 fixed to the frame 1 and a radially inwardly spaced apart circumferential direction of the ring portion 21. , And a slot portion 23 is formed between the tooth portions 22.

The stator winding 3 is wound through the slot 23, and the stator winding 3 is, as shown in FIGS. 3 and 4, a copper wire (wire material) through which electricity flows. ) 31 is fixed with an insulating varnish 32 and the periphery thereof is wrapped with insulating paper 33 to form a bundle.

Then, in this coil end 3e,
As shown in FIGS. 1 to 4, a ring-shaped heat conductor 11 is inserted between the coil end 3 e and the frame 1 for fixedly supporting the outer periphery of the stator core 2, and is filled and fixed with a silicone resin (fixing agent) 12. I do.

This filling and fixing is performed by filling a syrup-like silicon resin 12 between the coil end 3e and the frame 1 and inserting a ring-shaped heat conductor 11 therein. The silicon resin 12 around the heat conductor 11 is cured by ordinary temperature curing or heating while being held between the end 3e and the frame 1.

This ring-shaped heat conductor 11 is shown in FIG.
As shown in FIG. 2A, a ring shape may be formed to form a complete circumference. As shown in FIG. 2B, divided ring bodies 11Aa each having a shape obtained by dividing a ring in the circumferential direction are gathered together.
A ring-shaped heat conductor 11A may be formed as a whole. At this time, the space between the adjacent split ring bodies 11Aa may be in contact with each other, or some gap may be provided.

As shown in FIG. 2C, the ring-shaped heat conductor is a coil-shaped heat conductor, that is, a coil-shaped molded body 11
B can be used.

As shown in FIG. 2A, the heat conductor 11 is formed by laminating thin plates 11a of a metal such as aluminum or copper. By forming the metal heat conductor 11 by laminating the thin plates 11a, the eddy current induced by the current flowing through the coil end 3e is suppressed, and the eddy current loss of the metal laminate 11 is reduced.

Further, by using the metal thin plate 11a which can be easily formed by the press or the like, a ring-shaped or split ring-shaped shape can be easily formed, and the heat conductor 11 can be formed at low cost.

As shown in FIG. 2B, the heat conductor 11A can be made of a highly insulating ceramic. Aluminum oxide (alumina) can be used for this ceramic. If this ceramic having excellent insulating properties is used, eddy current loss hardly occurs, and the insulation between the coil end 3e and the frame 1 is reduced. Properties can be significantly increased.

Further, as shown in FIG. 2 (c), the heat conductor 11B is made of a metal wire 11B such as aluminum or copper.
a can also be formed in a coil shape. This coil-shaped formed body can be formed very easily simply by winding the wire 11Ba in a spiral shape, so that the cost is reduced.

As the fixing agent 12, a thermosetting resin such as an epoxy resin, a phenol resin or a polyimide resin can be used in addition to the silicone resin.

According to the above configuration, since the heat conductors 11, 11A, 11B having high heat conductivity are provided, the heat generated in the stator winding 3 is transferred to the heat conductors 11, 11A, 11B.
Heat can be transferred to the frame 1 via the base 11B, and the stator windings 3 can be efficiently cooled.

This cooling is performed by radiating heat from the cooling fins 9 provided on the frame 1 in the case of air cooling, and is performed by transferring heat to the cooling liquid circulating in the frame 1 in the case of liquid cooling. .

[0042]

As described above, according to the rotating electric machine according to the present invention, the following effects can be obtained.

By inserting a high heat transfer material between the coil end and the frame (housing), a high heat transfer property can be obtained in this portion. Heat can be transferred from the end to the frame via the heat conductor, cooling can be efficiently performed, the temperature of the permanent magnet of the rotor can be prevented from rising, and the magnetic force of the permanent magnet can be maintained.

By forming this heat conductor by laminating thin metal sheets having a remarkably high heat conductivity such as aluminum or copper and easily formed by pressing or the like, a ring-shaped or split ring-shaped shape can be easily formed. Thus, a thermal conductor having high thermal conductivity can be formed at low cost. In addition, due to the laminated structure of the thin plates, the eddy current induced by the current flowing through the coil end can be suppressed, and the eddy current loss generated by the metal can be reduced.

The heat conductor is made of a material having high heat conductivity such as aluminum oxide (alumina) or copper and having a high insulating property, so that a high heat conductivity is provided between the coil end and the frame. Insulation can be ensured.

By using a silicone resin, an epoxy resin, a phenol resin or a polyimide resin as a fixing agent, a strong adhesive force can be obtained. The cooling structure of the coil end part can be configured.

Therefore, a remarkable effect of reducing the temperature of the stator winding can be obtained even in the case of a closed structure, so that a rotating electric machine which can exhibit high output can be obtained.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a configuration of a rotating electric machine according to an embodiment of the present invention.

FIGS. 2A and 2B are views showing a heat conductor according to an embodiment of the present invention, wherein FIG. 2A is a perspective view of a ring-shaped heat conductor formed by laminating thin metal plates, and FIG. FIG. 4 is a perspective view of a heat conductor in a shape of a coil, and FIG.

FIG. 3 is a sectional view taken along the line AA of FIG. 1, showing a configuration of a rotor and a stator.

FIG. 4 is an enlarged view showing a portion of a stator winding in a section taken along line BB of FIG. 1;

FIG. 5 is a configuration diagram of a conventional rotating electric machine.

[Explanation of symbols]

 G Rotating electric machine 1 Frame 2 Stator 3 Stator winding 3e Coil end 7 Rotor 11, 11A, 11B Heat conductor 12 Adhesive 21 Stator core 71 Permanent magnet

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) H02K 21/14 H02K 21/14 G MF Term (Reference) 5H002 AB04 AB06 AC06 5H604 AA03 BB01 BB05 BB14 CC01 CC05 CC15 DA15 DA21 DA25 DB02 PB03 QA04 QA08 5H605 AA01 BB01 BB05 CC01 DD11 FF06 GG04 5H609 PP02 PP05 PP06 PP07 PP08 PP09 QQ23 RR58 RR69 RR73 RR74 5H621 HH01 JK07 JK11

Claims (6)

[Claims] 1. A rotor having a permanent magnet, a stator core disposed around the rotor and fitted inside a frame, and a rotor having a stator winding wound around the stator core. In the electric machine, a ring-shaped or split ring-shaped heat conductor is inserted between the coil end of the stator winding and the frame, and a bonding agent is provided between the heat conductor and the coil end and the frame. A rotating electric machine characterized by being filled and fixed. 2. The rotating electric machine according to claim 1, wherein the heat conductor is formed by laminating metal thin plates. 3. The rotating electric machine according to claim 1, wherein the heat conductor is formed of a metal coil-shaped formed body. 4. The rotating electric machine according to claim 1, wherein the heat conductor is formed of ceramic. 5. The rotating electric machine according to claim 1, wherein the fixing agent is formed of a silicone resin. 6. The rotating electric machine according to claim 1, wherein the fixing agent is formed of an epoxy resin or a polyimide resin.