CN211508745U - Rotor, motor and compressor - Google Patents

Abstract

The utility model discloses a rotor, a motor and a compressor, wherein the rotor comprises a rotor core, the edge of the rotor core is provided with a magnetic steel slot for inserting magnetic steel, and the cylindrical surface of the rotor core is provided with a plurality of sections of arc surfaces concentrically arranged, including a first arc surface intersected with a q axis and a second arc surface intersected with a d axis; first arc surface radius L1 and second arc surface radius L2 to and the maximum distance H of magnet steel groove apart from the rotor core centre of a circle satisfy L2 > H > L1, thereby rotor core is formed with first magnetic isolation bridge respectively at magnet steel groove along length direction's both ends. The rotor, effectively reduce motor noise vibration and improve the motor performance.

Description

Rotor, motor and compressor

Technical Field

The utility model belongs to the refrigeration field especially relates to a rotor, motor and compressor.

Background

At present, the country advocates a green development road, encourages enterprises to improve the motor efficiency, and the motor develops gradually to high energy efficiency, low noise direction, and the too big and motor torque fluctuation of tooth's socket torque leads to the motor vibration easily, and the magnetic leakage of magnetic isolation bridge and near d axle gather magnetic capacity and lead to the decline of performance.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a rotor, motor and compressor to effectively reduce motor noise vibration and improve the motor performance.

In order to achieve the above object, the utility model discloses a rotor, motor and compressor's concrete technical scheme as follows:

a rotor comprises a rotor core, wherein a magnetic steel slot for inserting magnetic steel is formed in the edge of the rotor core, and a plurality of sections of concentrically arranged arc surfaces are formed on the cylindrical surface of the rotor core and comprise a first arc surface intersected with a q axis and a second arc surface intersected with a d axis; first arc surface radius L1 and second arc surface radius L2 to and the maximum distance H of magnet steel groove apart from the rotor core centre of a circle satisfy L2 > H > L1, thereby rotor core is formed with first magnetic isolation bridge respectively at magnet steel groove along length direction's both ends.

Furthermore, a second magnetism isolating bridge is formed on the outer sides of the two ends of the magnetic steel groove along the width direction of the rotor core, and the second magnetism isolating bridge is connected with the first magnetism isolating bridge.

Furthermore, the two magnetic isolation bridges form an included angle of 90 degrees.

Further, from the first arc surface to the second arc surface, the distance from the outer wall of the rotor core to the center of the circle along the direction of the d axis gradually increases.

Furthermore, the center distance L of one end, close to the second arc surface, of the second magnetism isolating bridge and the radius L2 of the second arc surface meet the requirement that L/L2 is more than or equal to 0.96 and less than or equal to 0.98.

Furthermore, from one end of the second magnetism isolating bridge close to the second arc surface, the center distance of each point of the outer trimming edge of the rotor in the theta angle range is less than or equal to L, and theta is less than or equal to 8 degrees and more than or equal to 1 degree.

Further, the radius L1 of the first arc surface and the radius L2 of the second arc surface meet the requirement that L2-L1 are less than or equal to 0.75 mm.

An electric machine comprising the rotor.

A compressor comprises the rotor.

The utility model discloses a rotor, motor and compressor have following advantage:

1. the q-axis magnetic resistance is increased, the direction of a magnetic circuit is modified, excessive magnetic resistance torque is weakened, cogging torque and torque fluctuation are reduced, smaller cogging torque and torque fluctuation are beneficial to reducing noise vibration of the motor, the stability of the output torque of the motor is beneficial to improving, unbalanced force caused to a bearing is reduced, and therefore the effect of reducing noise vibration of the motor is achieved.

2. The magnetic leakage is reduced, a good magnetic gathering effect is facilitated to be formed, and the counter electromotive force of the motor is improved, so that the copper loss of the motor is reduced, and the effect of improving the efficiency of the motor is achieved.

Drawings

Fig. 1 is a schematic view of a rotor core structure of embodiment 2;

fig. 2 is a schematic view of a rotor core structure of comparative example 1;

FIG. 3 is a graph of back EMF of example 2;

FIG. 4 is a graph of back electromotive force of comparative example 1;

FIG. 5 is a cogging torque profile of example 2;

FIG. 6 is a cogging torque graph of comparative example 1;

FIG. 7 is a torque graph of embodiment 2;

fig. 8 is a torque graph of comparative example 1.

The notation in the figure is:

1. a rotor core; 2. a magnetic steel groove; 3. a first magnetic isolation bridge; 4. and a second magnetic isolation bridge.

Detailed Description

In order to better understand the purpose, structure and function of the present invention, the following description of the rotor, the motor and the compressor according to the present invention is made in detail with reference to the accompanying drawings.

Compressor, including motor and cylinder. The motor drives the roller in the cylinder to rotate through the crankshaft, compresses gas in the cylinder and applies work. The motor comprises a stator and a rotor, and the rotor is driven to rotate through electromagnetic induction. The rotor comprises a rotor core and magnetic steel, and a magnetic steel slot for inserting the magnetic steel is formed in the edge of the rotor core, so that the magnetic steel is distributed on the rotor core along the circumferential direction.

Example 1

As shown in fig. 1, the cylindrical surface of the rotor core is formed with a plurality of concentrically arranged arc surfaces, including a first arc surface intersecting the q-axis and a second arc surface intersecting the d-axis. First arc surface radius L1 and second arc surface radius L2 to and the maximum distance H of magnet steel groove apart from the rotor core centre of a circle satisfy L2 > H > L1, thereby rotor core is formed with first magnetic isolation bridge respectively at magnet steel groove along length direction's both ends.

Except the first magnetic isolation bridge, the rotor core is respectively provided with a second magnetic isolation bridge at the outer sides of the two ends of the magnetic steel groove along the width direction. The second magnetic isolation bridge is connected with the first magnetic isolation bridge, and the two magnetic isolation bridges form an included angle of 90 degrees.

The design of two sections magnetic isolation bridges increases the length of the magnetic isolation bridge, reduces magnetic leakage, simultaneously enables the iron core to be in closer contact with the magnetic steel, has smooth magnetic circuit, is favorable for magnetic gathering, and improves the counter electromotive force of the motor.

From the first arc surface to the second arc surface, the distance from the outer wall of the rotor core to the circle center along the direction of the d axis is gradually increased. In addition, the difference between the first circular arc surface radius L1 and the second circular arc surface radius L2 is 0.75mm at most. The first arc surface, the first magnetism isolating bridge and the second magnetism isolating bridge are connected in sequence, and the second magnetism isolating bridge and the second arc surface are connected through a plurality of sections of planes or arc surfaces.

Example 2

The rotor core in embodiment 2 is different from that in embodiment 1 in that a center distance L of one end of the second magnetic isolation bridge close to the second arc surface and a radius L2 of the second arc surface satisfy L/L2 of 0.96 or more and 0.98 or less. Meanwhile, from the end of the second magnetism isolating bridge close to the second arc surface, the center distance of each point of the outer trimming edge of the rotor in the theta angle range is less than or equal to L, and theta is less than or equal to 8 degrees and more than or equal to 1 degree.

Comparative example 1

As shown in fig. 2, the rotor core according to comparative example 1 is different from example 2 in that only the first magnetic isolation bridge is provided, and the second magnetic isolation bridge is not provided.

Test data for example 2 and comparative example 1

Fig. 3 is a graph of back electromotive force of example 2, and fig. 4 is a graph of back electromotive force of comparative example 1, and comparative analysis shows that: the back electromotive force is reduced due to the disappearance of the second magnetic isolation bridge, and is reduced from 47.5V to 47.3V.

Combining the following table, the back electromotive force 5 th harmonic increases, and the total distortion rate increases from 5.52% to 6.07%.

FIG. 5 is a cogging torque curve of example 2, FIG. 6 is a cogging torque curve of comparative example 1,

FIG. 7 is a torque curve of example 2, and FIG. 8 is a comparative analysis of the torque curve of comparative example 1, showing that: the cogging torque rises from 0.077 to 0.098, and the torque fluctuation rises from 6.5% to 7.7%, so that the control of L can reduce the back electromotive force distortion rate, improve the magnetic gathering capacity of the motor, and simultaneously reduce the torque fluctuation and the cogging torque.

Test data for example 2 and the remaining comparative examples

When theta is 2 degrees, different values of L/L2 are compared, and the test results are as follows:

L/L2	0.95	0.97	0.99
				rate of back emf distortion	7.44％	5.52％	5.40％
Torque ripple	6.38％	6.50％	8.90％

L/L2 being lower than 0.96 easily causes a significant increase in the rate of back EMF distortion, while L/L2 being higher than 0.98 causes a significant increase in torque ripple, while 0.96L 2L 0.98 torque ripple and back EMF distortion are overall optimal with the lowest noise vibration.

The variation of theta is easily influenced by the outer diameter of the rotor and the magnetic strength of the magnetic steel, the theta needs to be relatively increased when the rotor is larger or the Br value of the magnetic steel is higher, but the theta is not suitable for exceeding 8 degrees, the efficiency is easily lower, and the theta is too small to be lower than 1 degree, so that the processing is not facilitated.

It is to be understood that the present invention has been described with reference to certain embodiments, and that various changes or equivalents may be substituted for elements thereof by those skilled in the art without departing from the spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of the present application are intended to be covered by the present invention.

Claims (9)

1. A rotor comprises a rotor core, wherein the edge of the rotor core is provided with a magnetic steel groove for inserting magnetic steel, and the rotor is characterized in that a plurality of sections of arc surfaces which are concentrically arranged are formed on the cylindrical surface of the rotor core and comprise a first arc surface intersected with a q axis and a second arc surface intersected with a d axis; first arc surface radius L1 and second arc surface radius L2 to and the maximum distance H of magnet steel groove apart from the rotor core centre of a circle satisfy L2 > H > L1, thereby rotor core is formed with first magnetic isolation bridge respectively at magnet steel groove along length direction's both ends.

2. The rotor of claim 1, wherein the rotor core is formed with a second magnetic isolation bridge at the outer side of the two ends of the magnetic steel slot along the width direction, and the second magnetic isolation bridge is connected with the first magnetic isolation bridge.

3. A rotor according to claim 2, wherein the two segments of the magnetic-isolation bridge enclose an angle of 90 °.

4. The rotor of claim 2, wherein the distance from the outer wall of the rotor core to the center of the circle along the d-axis direction gradually increases from the first arc surface to the second arc surface.

5. The rotor as claimed in claim 2, wherein the center distance L of the second magnetism isolating bridge near one end of the second arc surface and the radius L2 of the second arc surface satisfy 0.96L/L2 0.98.

6. The rotor as claimed in claim 5, wherein from one end of the second magnetism isolating bridge close to the second arc surface, the center distance of each point of the outer trimming edge of the rotor within the theta angle range is less than or equal to L, and theta is greater than or equal to 1 degree and less than or equal to 8 degrees.

7. The rotor as claimed in claim 2, wherein the first circular arc radius L1 and the second circular arc radius L2 satisfy L2-L1 ≤ 0.75 mm.

8. An electrical machine comprising a rotor according to any one of claims 1 to 7.

9. A compressor, characterized by comprising a rotor according to any one of claims 1-7.

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