WO2019120312A1

WO2019120312A1 - Heat dissipation structure for electric motor

Info

Publication number: WO2019120312A1
Application number: PCT/CN2019/072223
Authority: WO
Inventors: 林中尉
Original assignee: 苏州阿福机器人有限公司
Priority date: 2017-12-24
Filing date: 2019-01-17
Publication date: 2019-06-27
Also published as: CN207625388U

Abstract

Provided in the present invention is a heat dissipation structure for an electric motor. The heat dissipation structure allows for direct cooling of the winding conductors, shortens the heat transfer path, increases heat dissipation effectiveness, and increases the power density and reliability of the motor. The heat dissipation structure includes a space in which a fluid heat-dissipation medium may be provided such that said medium may come into contact with the conductors that form the windings of the motor. Because the heat dissipation medium is provided in said space, said medium may directly or, via material having excellent heat conductivity, indirectly come into contact with the conductors, thus shortening the heat dissipation path and thereby avoiding heat dissipation of the conductors via insulating material, which has relatively poor heat conductivity. The rated power of motors using the present structure is considerably higher than that of conventional motors; and the power density and reliability of the motor are higher, particularly in scenarios in which the motors have high power density requirements, such as with vehicle-mounted power motors.

Description

Motor heat dissipation structure

Technical field

The invention relates to a heat dissipation structure of a motor, in particular to a heat dissipation structure of a motor for directly dissipating heat or rapidly indirectly dissipating a conductor of a motor.

Background technique

The heat dissipation of the motor is the key factor that restricts the power of the motor. When the motor is working, the coil, silicon steel sheet, rotor, etc. will heat up, especially the coil wire of the motor. Due to the existence of the resistor and the inductance, heat will be generated during the work. When the heat is greater than the heat dissipation, the motor temperature will rise continuously, causing the motor to burn out. Therefore, the motor can be prevented from overheating by reducing the rated power of the motor or shortening the working time of the motor, which greatly limits the motor capacity. Play.

For the outer stator motor coil of the conventional structure, the heat dissipation path of the external water-cooled motor is: wire->insulation paper->silicon steel sheet->motor shell->heat sink (water cooling), and the heat dissipation path of the internal oil-cooled motor is: wire-> Insulation paper -> silicon steel sheet -> cooling fluid, it can be seen that, at present, no matter which kind of motor, the heat dissipation route of the conductor is longer.

The heat dissipation of the conventional motor is indirect conduction heat dissipation. Referring to FIG. 1, the coil 1 is wrapped by the insulating paper 2 in the wire slot 4 on the core 3. In the heat transfer process, the thermal conductivity of the insulating paper is very poor, which greatly hinders the conduction of heat from the wire to the silicon steel sheet. In addition, the thermal conductivity of the silicon steel sheet is also limited, which is far less than the thermal conductivity of copper and aluminum. Therefore, conventional There are serious deficiencies in the heat dissipation capability of the motor.

Summary of the invention

SUMMARY OF THE INVENTION An object of the present invention is to provide a motor heat dissipation structure capable of directly cooling a coil conductor, shortening a heat transfer line, improving heat dissipation efficiency, and improving power density and reliability of the motor.

The motor heat dissipation structure of the present patent has a space in contact with a conductor constituting a motor coil having a flowing heat dissipation medium.

The invention has the beneficial effects that since the heat dissipating medium is in contact with the conductor directly or through a material with good thermal conductivity in the space, the heat dissipation path is shortened, and the heat dissipation of the conductor through the insulator with poor thermal conductivity is avoided, thereby enhancing the heat dissipation effect. This type of cooling can be referred to as direct cooling. The motor with this structure can greatly improve the rated power than the rated power of the conventional motor, and improve the power density and reliability of the motor. It is especially suitable for applications where the power density of the motor is high, such as a vehicle power motor.

The heat sink media can be recycled or not recycled. When recycled, the heat dissipating medium absorbs heat of a conductor or the like while passing through the space, and then flows to an external flow path communicating with the space to cool down, and then flows back into the space to form a circulating flow of the heat dissipating medium.

When the heat dissipating medium is not recycled, such as air as a heat dissipating medium, the heat dissipating medium absorbs heat of a conductor or the like while passing through the space, and then flows to the outside of the space to directly discharge.

As a further improvement to the heat dissipation structure of the motor, the space is any one or more of a space between the conductor and the conductor, a space between the conductor and the iron core, and a space between the conductor and the insulator. That is, the space is the space between the conductor and the conductor, and/or the space between the conductor and the core, and/or the space between the conductor and the insulator. If the heat dissipating medium is in direct contact with the conductor in the space, the heat dissipating medium may be any fluid that can dissipate heat and does not cause a short circuit of the motor under certain conditions, such as liquid, gas, and the like. If the heat dissipating medium is indirectly in contact with the conductor in the space, if a hollow tube is disposed in the space, the heat dissipating medium flows in the hollow tube, and the insulation performance of the heat dissipating medium may be reduced according to the situation.

As a further improvement to the heat dissipation structure of the motor, a hollow tube in direct contact with the conductor is disposed in the space, and the heat dissipation medium flows in the hollow tube. The advantage of providing a hollow tube is that, for a circulating medium, the hollow tube is conveniently connected to the external line to form a passage for the circulating flow of the heat dissipating medium, and the hollow tube may have any shape that is favorable for heat conduction.

As a further improvement to the heat dissipation structure of the motor, a heat pipe in direct contact with the conductor is disposed in the space. A heat pipe is an existing heat exchange device. It uses the gas-liquid conversion of the refrigerant in the heat pipe to transfer heat out.

As a further improvement to the motor heat dissipation structure, the conductor is a conductor having a surface having protrusions and/or depressions to increase the heat dissipation area. Of course, the conductor cross section may be any shape, such as a circular cross-section conductor, a rectangular cross-section conductor, a flat-section conductor, a surface having projections and/or depressions, and the like, which are advantageous for heat dissipation, and the like.

As a further improvement of the heat dissipation structure of the motor, an unsealed insulator is disposed between the coil and the iron core, and the insulator, the iron core, and the conductor constitute the space, or the insulator and the adjacent conductor constitute the space. In other words, the space is formed between the insulator, the iron core, and the conductor in common or in part.

The space is any one or more of a space between a part or all of the conductors, a space between the partial or all conductors and the slot walls on the core. That is, the space is the space between the partial or all conductors and/or the space between the partial or all conductors and the slot walls on the core.

As a further improvement to the heat dissipation structure of the motor, a closed insulator is disposed between the coil and the iron core, and the insulator and the adjacent conductor jointly or partially constitute the space.

DRAWINGS

1 is a schematic view of a conventional heat dissipation structure of a motor.

2 is a schematic view showing the heat dissipation structure of the motor of Embodiment 1.

Figure 3 is a schematic view of a conductor having protrusions or depressions on its surface.

4 is a schematic view showing the heat dissipation structure of the motor of Embodiment 2.

In the figure, the coil 1, the insulating paper 2, the iron core 3, the wire groove 4, the conductor 5, the space 6, the space 7, the heat dissipating medium 8, and the heat pipe 9.

Detailed ways

Example 1:

Referring to the heat dissipation structure of the motor shown in FIG. 2, the coil 1 is wrapped in the wire slot 4 of the iron core 3 by the unsealed insulator 2. The inner and outer sides of the wire groove respectively have a space surrounded by an insulator, a core and a conductor 6. A plurality of spaces 7 are enclosed between the insulator and the adjacent conductors. The heat dissipating medium 8 flows from the head end of the

space

6 and 7 at one end of the iron core, flows out from the tail end located at the other end of the iron core, and the heat dissipating medium directly contacts the wire. During operation, the heat-dissipating medium flows under the action of pressure to cool the conductor, and the heat-dissipating medium flows under pressure to the external heat sink that communicates with the end of the

space

6, 7 to dissipate the heat, and the heat-dissipating medium is again The head ends of the

spaces

6, 7 enter the motor to form a cooling cycle. The heat dissipating medium 8 can be any fluid that can dissipate heat and does not cause a short circuit of the motor under certain conditions. In this way, the heat transfer path is short, the cooling capacity is greatly improved, and the cooling medium for cooling, in addition to providing direct cooling to the coil, can also provide cooling for silicon steel sheets, magnetic steel, other conductors, and the like. The motor with this structure can greatly improve the rated power than the rated power of the conventional motor, and improve the power density and reliability of the motor, especially suitable for the occasion where the power density of the motor is high.

The space for the heat dissipation medium to flow may be a space between the conductors, a space between the conductor and the iron core, or a combination of the two. The conductor 5 may also be a conductor having a convex or concave surface to increase the heat dissipation area (see Fig. 3).

The space between the conductors may directly flow through the heat dissipating medium, or may indirectly flow the heat dissipating medium. For example, a hollow tube is disposed between the conductors of the winding, and the heat dissipating medium is circulated in the hollow tube.

Example 2:

Referring to the heat dissipation structure of the motor shown in FIG. 4, the coil 1 is wrapped in a closed slot 4 of the insulating paper 2, and a plurality of spaces 7 are defined between the insulator and the adjacent conductors. The evaporation end of the heat pipe 9 projects into the space 7, and the condensation end of the heat pipe 9 is outside the core. The refrigerant is enclosed in the heat pipe and flows by pressure, and heat is conducted to the refrigerant through the pipe wall. The heat of the conductor is transmitted by the gas-liquid conversion of the refrigerant in the heat pipe.

Claims

A motor heat dissipating structure characterized in that it has a space in contact with a conductor constituting a motor coil having a flowing heat dissipating medium.
A heat dissipation structure for a motor according to claim 1, wherein said space is any one or more of a space between the conductor and the conductor, a space between the conductor and the iron core, and a space between the conductor and the insulator. Kind.
The heat dissipation structure for a motor according to claim 1, wherein a hollow tube in direct contact with the conductor is disposed in the space, and the heat dissipation medium flows in the hollow tube.
A heat dissipation structure for a motor according to claim 1, wherein said space is provided with a heat pipe in direct contact with the conductor.
A heat dissipation structure for a motor according to claim 1, wherein said conductor is a conductor having a surface having depressions and/or projections to increase a heat dissipation area.
The heat dissipation structure for a motor according to claim 1, wherein an insulator that is not closed is disposed between the coil and the iron core, and the insulator, the iron core, and the conductor constitute the space, or the insulator and the adjacent conductor constitute the space.
A heat dissipating structure for a motor according to claim 1, wherein said space is any one of a space between a part or all of a conductor, a space between a part or all of a conductor and a groove wall of a core. Kind or several.