KR20010064011A - Structure for cooling motor in turbo compressor - Google Patents

Abstract

PURPOSE: A motor cooling structure of a turbo compressor is provided to improve the cooling efficiency of a motor by cooling heat generated at a stator, a rotor, and winding coils, thereby increasing the efficiency and the reliability of the motor. CONSTITUTION: In a motor cooling structure of a turbo compressor, a motor includes a stator(210) fixedly coupled with a motor chamber and a rotor(220) rotatably connected to the inside of the stator, wherein the stator is formed by coupling a plurality of winding coils(230) with a cylindrical stator core(212) having a rotor insertion hole(211), the rotor formed in a cylindrical type is inserted into the rotor insertion hole, an air gap is formed between the outer peripheral surfaces of the stator and the rotor, and a passage groove is formed at the air gap by rotation of the rotor for flowing fluid passing through the air gap.

Description

Motor cooling structure of turbo compressor {STRUCTURE FOR COOLING MOTOR IN TURBO COMPRESSOR}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor of a turbo compressor, and more particularly, to a motor cooling structure of a turbo compressor capable of effectively cooling heat generated when a motor is driven.

Generally, a turbo compressor is a machine that compresses a gas by rotating a vane. FIG. 1 shows a turbocompressor filed by the present applicant with the patent application P97-64567. As shown therein, the turbocompressor includes a first compression chamber 10 having a suction port 1 and a discharge port 21. The second compression chamber 20 is formed on both sides and the motor chamber 30 is formed in the center and the first compression chamber 10 and the second compression chamber 20 in communication with the motor chamber ( The airtight container 100 including the gas flow passage 40 formed to communicate with the 30, the motor 200 mounted on the motor chamber 30 to generate a driving force, and one end of the first compression chamber ( A driving shaft 300 inserted into the second compression chamber 20 and coupled to the second compression chamber 20 and coupled to the motor 200 to transmit a driving force of the motor 200, and the first compression chamber 10. The gas flow path 40 is coupled to the end of the drive shaft 300 so as to be rotatable by compressing the gas flowing into the inlet 1. The first impeller 400 to flow to the second compression chamber 20 and the second compression chamber 20 is coupled to the end of the drive shaft 300 so as to be rotatable in the second compression chamber 20 to be compressed in one stage. And a second impeller 500 which compresses the gas introduced into the second stage and discharges the gas into the discharge port 21.

A thrust bearing 700 for supporting the drive shaft 300 in the axial direction is coupled to both sides of the drive shaft 300, and a radial bearing for radially supporting the drive shaft 300 in the center of the drive shaft 300 is provided. 800 are respectively coupled to be located at both sides of the motor 200.

Reference numeral 600 denotes an accumulator.

Referring to the operation of the turbo compressor as described above is as follows.

First, when power is applied, the driving force of the motor 200 and the driving force of the motor 200 are transmitted to the driving shaft 300 to rotate the driving shaft 300. The first impeller 400 and the second impeller 500 coupled to both ends of the drive shaft 300 are rotated by the rotation of the drive shaft 300, respectively. The low temperature low pressure refrigerant gas, which has passed through the accumulator 600 by the rotational force of the first impeller 400 and the second impeller 500, is introduced into the first compression chamber 10 through the inlet 1 and is provided in the first stage. The compressed first compressed refrigerant gas is introduced into the second compression chamber 20 through the gas flow path 40, and the first compressed refrigerant gas introduced into the second compression chamber 20 is the second compression chamber ( 20 is compressed in two stages and is discharged through the discharge port 21. The refrigerant gas discharged through the discharge port 21 flows into a condenser (not shown) constituting a refrigeration / air conditioning cycle.

On the other hand, the motor 200 for rotating the first and second impeller 400, 500 is 50000 ~ 60000 RPM to generate a compression force corresponding to the size change of the first and second impeller 400, 500 Motors capable of high speeds of rotation should be applied. As an example of such a turbo compressor motor, as shown in FIG. 2, a stator 210 fixedly coupled to the motor chamber 30 and a rotor rotatably coupled to the inside of the stator 210. Rotor 220). The stator 210 has a predetermined length and a plurality of winding coils 230 are coupled to a cylindrical stator core 212 having a rotor insertion hole 211 into which a rotor 220 is inserted. Is done. In addition, the stator core 212 is formed by stacking a plurality of core pieces in the form of a sheet.

The rotor 220 is formed in a cylindrical shape having a predetermined length and inserted into the rotor insertion hole 211 of the stator. The rotor 220 usually has a core piece having a plurality of through holes stacked therein to form a rotor core 221, and a core piece having aluminum and the like inserted into the through hole formed by the through holes of the stacked core pieces. It consists of a fixing member 222 for fixing them, the fixing member 222 is a material such as aluminum is inserted by a processing method such as die casting.

When the rotor 220 is inserted into the rotor insertion hole 211 of the stator 210 and assembled, a gap is formed between the stator 210 and the rotor 220, and the gap is called an air gap. gap) (G).

When the motor of the turbo compressor as described above is sequentially applied power to the winding coil 230, the rotor 220 is rotated by the electromagnetic interaction force and the rotor (by the rotation of the rotor 220) The drive shaft 300 coupled to 220 is rotated.

However, when the motor of the turbo compressor as described above rotates at a high speed, heat is generated in the rotor 220 and the stator 210, and the heat is mostly the winding coil 230, the stator 210, and the rotor 220. Induced by Eddy Current Loss (Eddy Current Loss) occurring in the) and as the amount of heat generated such as not only lowers the efficiency of the motor but also has a problem of lowering the reliability.

SUMMARY OF THE INVENTION An object of the present invention devised in view of the above problems is to provide a motor cooling structure of a turbo compressor that can effectively cool heat generated in a motor that generates a driving force during operation of the compressor.

1 is a cross-sectional view showing an example of a general turbo compressor,

2 is a front sectional view showing a motor of a conventional turbo compressor;

3 is a cross-sectional view of a motor provided with a turbo compressor motor cooling structure of the present invention;

4 is a perspective view showing another modification of the turbo compressor motor cooling structure of the present invention;

5 is a plan view showing a method of forming a flow path groove constituting the turbo compressor motor cooling structure of the present invention;

6 is a cross-sectional view showing another embodiment of the turbo compressor motor cooling structure of the present invention;

7 is a cross-sectional view showing an operating state of the turbo compressor motor cooling structure of the present invention.

(Explanation of symbols on the main parts of drawing

210; Stator 211; Rotor insertion hole of stator

220; Rotor G; Air gap

F; Eurohome

In order to achieve the object of the present invention as described above, the rotor is inserted into the rotor insertion hole of the stator, and fluid is formed by the rotation of the rotor in an air gap formed by the inner peripheral surface of the rotor insertion hole of the stator and the outer peripheral surface of the rotor. There is provided a motor cooling structure of a turbo compressor, wherein a flow path groove is formed to flow therethrough.

Hereinafter, the turbo compressor motor cooling structure of the present invention will be described according to the embodiment shown in the accompanying drawings.

3 illustrates an example of the turbo compressor motor cooling structure of the present invention. Referring to this, first, the motor of the turbo compressor is stator 210 and the stator fixedly coupled to the motor chamber 300. The rotor 210 is rotatably coupled to the inside, and the stator 210 has a predetermined length and the rotor insertion hole 211 into which the rotor 220 is inserted. Is formed by coupling a plurality of winding coils 230 to a stator core 212 having a cylindrical shape, and the rotor 220 is formed in a cylindrical shape having a predetermined length to rotate the rotor of the stator 210. It is inserted into the insertion hole 211. An interval between the stator 210 and the rotor 220, that is, the outer circumferential surface of the rotor insertion hole 211 of the stator 210 and the outer circumferential surface of the rotor 220 forms an air gap G. In addition, a flow path groove F through which the fluid flows through the air gap G is formed by the rotation of the rotor 220 in the air gap G. The flow path groove F is preferably formed on the inner circumferential surface of the rotor insertion hole 211 of the stator 210 into which the rotor 220 is inserted. The flow path groove F may be formed as a spiral shaped groove, and as shown in FIG. 4, may be formed as a spiral groove.

The stator core 212 constituting the stator 210 is formed by stacking a plurality of core pieces in the form of a sheet, and in this case, a method of forming the flow path groove F is illustrated in FIG. 5, as shown in FIG. 5. In the groove a) and stacking the core pieces S on which the grooves a are formed, and then rotating each of the stacked core pieces S slightly into the grooves a of the respective core pieces S. The flow path groove F is connected by the formation.

In addition, as another modification of the present invention, as shown in FIG. 6, the flow path groove F is formed on the outer circumferential surface of the rotor 220 constituting the air gap G. The flow path groove F may be formed as a spiral groove or a spiral groove on the outer circumferential surface of the rotor 220. When the rotor core 221 of the rotor 220 is laminated with a plurality of core pieces, grooves are formed in the core pieces in the same manner as the stator, and the core pieces in which the grooves are formed are rotated slightly in the stacked state, and the flow path The groove F is formed.

In addition, as another modification of the present invention, the flow path grooves F are formed on the inner circumferential surface of the rotor insertion hole 211 of the stator 210 and the outer circumferential surface of the rotor 220, respectively.

The drive shaft 300 is fixedly coupled to the rotor 220, and the impeller is coupled to both ends of the drive shaft, respectively.

Hereinafter, the operational effects of the turbo compressor motor cooling structure of the present invention will be described.

First, when power is applied, when a current flows in the winding coil 230 sequentially, the rotor 220 rotates at high speed by the interaction force, and is coupled to the rotor 220 by the high speed rotation of the rotor 220. The driven shaft 300 is rotated. As the first and second impellers 400 and 500 rotate as the drive shaft 300 rotates, the refrigerant gas sucked in the first compression chamber 10 is first compressed, and then, in the second compression chamber 20. Two-stage compression is to be discharged through the discharge port 21. As described above, a part of the refrigerant gas flows into the motor chamber 30 and the refrigerant gas flows into the motor chamber 30 in the process of compressing the refrigerant gas in the first and second stages, as shown in FIG. 7. As the 220 rotates, the flow path grooves F pass by the suction force of the flow path grooves F formed between the stator 210 and the air gap G of the rotor 220. As the refrigerant gas passes through the flow path groove F, the coolant gas cools heat generated in the stator 210, the rotor 220, and the winding coil 230.

As described above, the motor cooling structure of the turbo compressor according to the present invention cools heat generated in the stator and the rotor and the winding coil while the refrigerant gas flows through the flow path groove formed in the air gap between the stator and the rotor. By doing so, the cooling performance of the motor is increased, thereby increasing the efficiency and reliability of the motor.

Claims (3)

The rotor is inserted into the rotor insertion hole of the stator to form a flow path groove through which the fluid flows through the rotation of the rotor in the air gap formed by the inner peripheral surface of the rotor insertion hole of the stator and the outer peripheral surface of the rotor. Motor cooling structure of turbo compressor made. The motor cooling structure of the turbocompressor according to claim 1, wherein the flow path grooves are formed on the outer circumferential surface of the rotor insertion hole of the stator, the outer circumferential surface of the rotor or the inner circumferential surface of the rotor insertion hole of the stator, and the outer circumferential surface of the rotor, respectively. The motor cooling structure of a turbo compressor of claim 1, wherein the flow path grooves are formed in a spiral shape.