KR20200093868A - Structure for cooling of a motor - Google Patents

Abstract

The present invention relates to a cooling structure of a motor in which a cooling path is formed in a stator core of the motor to efficiently cool heat generated from the stator core so as to prevent damage to the motor and contribute performance stabilization. To this end, the cooling structure of a motor comprises a plurality of cooling grooves and at least one cooling path.

Description

Structure for cooling of a motor

The present invention relates to a cooling structure of a motor that cools heat generated in the stator core of the motor.

A motor is an energy converter that converts electrical inputs into mechanical outputs, and the difference between inputs and outputs is called efficiency because some of the inputs are not output and are lost.

Loss occurs in the form of heat, and exists as a barrier that limits the output and uptime of motor drive. The method of increasing the torque of either side of two motors having the same shape and control method is a method of increasing the input of the motor to increase the output.

At this time, an increase in input means an increase in current, and an increase in current generally increases the copper loss, which occupies the largest loss of the motor, to the square (square). Due to this, the temperature is greatly increased, and the motor is damaged or the driving time is shortened.

1 is a front sectional view showing an example of a stator core cooling structure of a conventional motor, FIG. 2 is a side sectional view of a stator core cooling structure of a conventional motor, and FIG. 3 is a heat transfer barrier in a stator core cooling structure of a conventional motor It is a figure illustrating.

1 to 3, the conventional motor stator core cooling structure includes an outer housing 11 surrounding an outer housing 11 and a stator core 12 of the motor 10. The space between both sides of the inner housing 13 is utilized as a cooling path 14.

A copper source installed in a slot 12a of the stator core 12 (not shown in the drawing) is a heat source that generates the greatest heat (Copper loss), which is a cooling path (Cooling path) (14) Heat is transferred from the heat source to the coolant due to the temperature deviation from the coolant in the system, thereby maintaining the temperature of the system.

At this time, the heat generated from the rotor (not shown in the drawing) spaced apart with an air-gap at the inner edge of the stator core 12 slot 12a is an air-gap. It is assumed that the stator core 12 is not transferred by the high density air layer.

As heat is transferred from the heat source to the coolant, a gap due to a tolerance for an assembly process between the inner housing 13 made of aluminum and the stator core 12 made of iron, and the effect of different materials contributing to heat transfer Since the thermal transfer coefficient, which is a prescribed physical property value, is different, a thermal transfer barrier that prevents heat transfer exists as shown in FIG. 3.

At this time, since the thickness of the inner housing 13 must be designed to be strong in order to strengthen the durability for maintaining the empty space that becomes the cooling passage 14, this is a cause of increasing the thermal resistance in the heat transfer path, and the amount of heat transfer It acts as a factor to reduce.

On the other hand, in the Korean Patent Registration No. 10-0665048 (December 28, 2006), a rapid cooling structure of a motor using a heat pipe to increase heat dissipation effect by attaching a heat pipe to the motor surface to cool the heat generated when the motor rotates Are proposing.

This technology transfers heat generated by the motor to the outside by installing a heat pipe on the surface of the motor, and the heat transferred to the heat pipe is discharged through a heat dissipation fin installed at the rear of the motor. In addition, a blower is attached to the motor end to help cool the heat sink fins and motor.

The present inventor has studied the cooling structure of a motor that can cool the heat generated in the stator core more efficiently by forming a cooling path in the stator core itself of the motor.

Republic of Korea Registered Patent No. 10-0665048 (December 28, 2006)

An object of the present invention is to provide a cooling structure of a motor capable of more efficiently cooling heat generated in the stator core by forming a cooling path in the stator core itself of the motor.

According to an aspect of the present invention for achieving the above object, the cooling structure of the motor and a plurality of cooling grooves that are radially through the outer periphery of the stator core (Stator core); It is embedded along a plurality of cooling grooves, and includes at least one cooling path that discharges heat generated in the stator core through the cooling water to the outside of the motor.

According to an additional aspect of the present invention, the cooling passage may be a cooling pipe.

According to an additional aspect of the present invention, the cooling passage may be a cooling tube.

According to an additional aspect of the present invention, the cooling passage may have an inlet through which cooling water is introduced and an outlet through which cooling water is discharged.

According to an additional aspect of the present invention, the cooling passage may have an inlet through which cooling water is introduced and an outlet through which cooling water is discharged.

The present invention can cool the heat generated in the stator core more efficiently by forming a cooling path in the stator core itself of the motor, thereby preventing damage to the motor and stabilizing performance. have.

1 is a front sectional view showing an example of a stator core cooling structure of a conventional motor.
2 is a side cross-sectional view of a stator core cooling structure of a conventional motor.
3 is a view illustrating a heat transfer barrier in the stator core cooling structure of a conventional motor.
4 is a front sectional view of a cooling structure of a motor according to the present invention.
5 is a side cross-sectional view of a cooling structure of a motor according to the present invention.
6 is a view illustrating an inlet and an outlet forming direction of a cooling passage of a cooling structure of a motor according to the present invention.
7 is a view illustrating an increase in the stator core thickness of the cooling structure of the motor according to the present invention.

Hereinafter, the present invention will be described in detail so that those skilled in the art can easily understand and reproduce it through preferred embodiments described with reference to the accompanying drawings. Although specific embodiments are illustrated in the drawings and related detailed description is described, it is not intended to limit the various embodiments of the invention to specific forms.

In the description of the present invention, when it is determined that detailed descriptions of related known functions or configurations may unnecessarily obscure the subject matter of embodiments of the present invention, detailed descriptions thereof will be omitted.

When an element is said to be "connected" or "connected" to another component, it is understood that other components may be directly connected to or connected to the other component, but there may be other components in between. It should be.

On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that no other component exists in the middle.

4 is a front sectional view of a cooling structure of a motor according to the present invention, and FIG. 5 is a side sectional view of a cooling structure of a motor according to the present invention. 4 and 5, the motor 100 includes a stator core 110 in which a plurality of slots 111 and teeth 112 are formed at an inner edge. And a housing 120 including an upper housing 121 and a lower housing 122 that cover the outer edge of the stator core.

In addition, the motor 100 rotates around the center of the stator core in an axis, but a rotor (not shown in the drawing) to which a plurality of magnets (not shown) is attached to the outer edge and slots and teeth of the stator core It includes a coil to be installed (not shown in the drawing).

When current is applied to the coils installed in the slots and teeth of the stator core, a magnetic flux is generated in the air gap between the magnet of the inner edge of the stator core and the outer edge of the stator, and the rotor rotates by generating repulsive force in the magnet of the rotor. .

That is, the motor 100 converts electrical input through a coil installed in the stator core to a mechanical output called rotation of the rotor. However, the entire input cannot be converted to the output, and a part of the input cannot be output, resulting in loss. Loss occurs in the form of heat, and exists as a barrier that limits the output and uptime of motor drive.

Therefore, since the heat generated in the motor is a factor that damages the motor and degrades the motor performance, it is necessary to cool the heat generated in the motor to prevent the motor from being damaged and to stabilize the motor performance.

The heat generated in the motor 100 is mainly generated in the stator core 110, and the present invention efficiently cools the heat generated in the stator core 110 to prevent damage to the motor and stabilize the performance of the motor. We propose a motor cooling structure.

The cooling structure of the motor according to the present invention is embedded in a plurality of cooling grooves 130 and a plurality of cooling grooves radially passing along the outside of the stator core 110, and the stator core through cooling water movement It includes at least one cooling path (Cooling path) 140 for discharging the heat generated in the outside of the motor.

At this time, a plurality of cooling grooves 130 radially through the outer periphery of the stator core 110 may be formed through the upper and lower surfaces of the stator core 110, and the spacing of the cooling grooves 130 may be It may be regular or irregular, and the number of cooling grooves 130 may be an even number or an odd number.

Meanwhile, the cooling passage 140 may be a cooling pipe or a cooling tube. The material of the cooling passage 140 may be an aluminum material having excellent thermal conductivity, but is not limited thereto.

For example, when a thin aluminum cooling pipe or a cooling tube is used as the cooling passage 140, a thermal transfer barrier that hinders heat transfer in the heat transfer path can be minimized.

Copper loss due to a coil installed in the stator core 110 occurs in a heat form and is transmitted to the outside through the stator core 110. In this process, heat is transferred to the cooling passage 140 that is buried along a plurality of cooling grooves 130 radially through the stator core 110.

At this time, the cooling water is continuously flowing into the inlet of the cooling passage 140, and the cooling water is discharged through the outlet. The heat transferred to the cooling passage 140 is discharged to the outside of the motor 100 through cooling water moving the cooling passage 140, so that the motor 100 is cooled.

On the other hand, the problem of reducing the cooling efficiency at the outlet side caused by the relatively high cooling water temperature at the outlet side compared to the cooling water temperature at the inlet side of the cooling passage 140 is a thin aluminum material having a small inner diameter. The cooling pipe or the cooling tube may be somewhat improved through rapid circulation of the cooling water due to an increase in the cooling water flow rate by using the cooling passage 140.

By implementing in this way, the present invention can cool the heat generated in the stator core more efficiently by forming a cooling path in the stator core itself of the motor, thereby preventing damage to the motor and stabilizing performance. Can contribute.

6 is a view illustrating an inlet and an outlet forming direction of a cooling passage of a cooling structure of a motor according to the present invention. As shown in FIG. 6(a), the cooling passage 140 may be implemented such that an inlet through which cooling water is introduced and an outlet through which cooling water is discharged are formed in the same direction.

Alternatively, as illustrated in FIG. 6B, the cooling passage 140 may be implemented such that an inlet through which cooling water is introduced and an outlet through which cooling water is discharged are formed in opposite directions.

7 is a view illustrating an increase in the stator core thickness of the cooling structure of the motor according to the present invention. The stator core 110 of the cooling structure of the motor according to the present invention is formed with a plurality of cooling grooves 130 that are radially through the outer periphery, and the cooling passages 140 are buried along the plurality of cooling grooves. As shown in Fig. 7(b), the thickness of the stator core is increased as compared to the thickness A of the conventional stator core as shown in 7(a).

A motor having a cooling structure of a motor according to the present invention having an increased stator core thickness can improve core saturation occurring at high current due to an increase in the stator core thickness.

When current flows through the coil wound around the stator core, magnetic flux flows through the iron core. Iron core saturation increases the magnetic flux when the current increases, but when it exceeds a certain limit, the magnetic flux cannot increase even when the current increases.

In the case of an annular stator core, since the magnetic flux is proportional to the current and inversely proportional to the radius of the stator core, when the thickness of the stator core increases, the time to reach the iron core saturation increases, so the iron core generated at high current due to the increase in the stator core thickness Core saturation can be improved.

When the iron core saturation is improved, when the current is applied to the coil installed in the stator core, the torque ripple, which is the amplitude of the torque, which is the torsional moment that rotates the rotor, is reduced. It can also contribute to securing stability and quietness.

As described above, the present invention can cool the heat generated in the stator core more efficiently by forming a cooling path on the stator core itself of the motor, thereby preventing damage to the motor and stabilizing performance Can contribute to

The various embodiments disclosed in the specification and drawings are merely presented as specific examples for ease of understanding, and are not intended to limit the scope of various embodiments of the present invention.

Accordingly, the scope of various embodiments of the present invention includes, in addition to the embodiments described herein, all modified or modified forms derived based on the technical spirit of the various embodiments of the present invention are included in the scope of various embodiments of the present invention Should be interpreted as

The present invention can be used industrially in the field of motor cooling technology and its application technology.

100: motor
110: stator core
111: slot
112: Chi
120: housing
121: upper housing
122: lower housing
130: cooling groove
140: cooling passage

Claims (5)

A plurality of cooling grooves radially through the outer periphery of the stator core;
At least one cooling path which is buried along the plurality of cooling grooves and discharges heat generated in the stator core through the cooling water to the outside of the motor;
The cooling structure of the motor that contains. According to claim 1,
Cooling passage:
Cooling structure of the motor, which is a cooling pipe. According to claim 1,
Cooling passage:
Cooling structure of the motor, which is a cooling tube. The method according to any one of claims 1 to 3,
Cooling passage:
The cooling structure of the motor in which the inlet through which coolant is introduced and the outlet through which coolant is discharged are formed in the same direction. The method according to any one of claims 1 to 3,
Cooling passage:
Cooling structure of the motor in which the inlet (inlet) to which the cooling water is introduced and the outlet (outlet) through which the cooling water is discharged are formed in opposite directions.

Images