CN107659103B - An asynchronous starting permanent magnet synchronous motor - Google Patents

Abstract

The invention relates to an asynchronous starting permanent magnet synchronous motor, which includes a stator winding. The stator winding is arranged in a slot of a stator core. It is characterized in that a rotor one is provided in the stator core, and a rotor two is provided in the rotor one, wherein: There is a flat-bottomed squirrel cage slot on the outer circle of the rotor one, and there are cast aluminum or cast copper squirrel cage guide bars in the squirrel cage slot; the second rotor is composed of two sections of rotor and two iron cores, and the two sections of rotor and two iron cores twist one stator and two slots. Spacing angle, there are magnetic steel grooves on the two cores of the rotor, and magnetic steel is installed in the magnetic steel grooves. Non-magnetic steel structural parts are placed on the outer circle of the central axis of the two poles of the two cores of the rotor. The bottom of the squirrel cage groove to the rotor The distance between the inner holes of rotor one and the steel structure of rotor two jointly play the role of magnetic isolation. The invention solves the production efficiency problem of the stator off-line and suppresses the influence of stator tooth harmonics on the operation of the motor. At the same time, the inter-pole magnetic leakage problem caused by the segmented torsion angle of rotor 2 is solved by adding steel structural parts.

Description

An asynchronous starting permanent magnet synchronous motor

Technical field

The invention relates to an asynchronous starting permanent magnet synchronous motor and belongs to the field of electric motors.

Background technique

The permanent magnet synchronous motor currently used in industry cannot complete the starting process by itself if it is connected to the power grid without a frequency converter or controller. Asynchronous starting permanent magnet synchronous motors use the squirrel cage widely used in asynchronous motors to complete the starting process, which solves this problem well. After the motor is running normally, the squirrel cage stops functioning. In fact, it is the operation of an ordinary permanent magnet synchronous motor. During the operation of the permanent magnet synchronous motor, the stator and rotor tooth harmonics often affect the torque output of the motor. , causing problems such as increased motor losses and excessive vibration and noise. Generally speaking, in order to eliminate stator tooth harmonics, methods such as stator inclined slots or rotor inclined poles can be used. Stator inclined poles will have a great impact on the automation and efficiency of the stator off-line, and at the same time increase the stator resistance and loss. , and the rotor tilt pole is difficult to implement due to the placement of the rotor squirrel cage and magnets.

In response to the above problems, some patents have been applied for in this field. In terms of rotor oblique poles, the patent number ZL200520046139.6, named Asynchronous Start Permanent Magnet Synchronous Motor Rotor Structure, proposes a method of segmented oblique poles of the rotor, but the size of its torsion angle is subject to the need to ensure the conduction of the squirrel cage conductor. Process constraints. Moreover, the magnets are arranged in an arc shape, and are arranged in an arc-like shape along the bottom of the rotor squirrel cage slot. The angle at which the magnets are placed at each pole is only two-thirds of the angle occupied by each pole. In terms of rotor segmentation, the patent number ZL201110250809.6, titled Self-Starting Permanent Magnet Synchronous Motor Rotor, proposes to separate the squirrel cage rotor and the synchronous rotor, but it only skews the squirrel cage rotor and does not tilt the rotor. The magnets are also arranged in a circular arc along the bottom of the rotor squirrel cage slot. The above-mentioned patent does not protect the placement of "V" and "U" shaped magnets. At the same time, due to its own limitations, it does not eliminate stator tooth harmonics and cannot achieve good technical results.

Contents of the invention

The technical problems to be solved by this invention are: the production efficiency problem of stator off-line and suppressing the influence of stator tooth harmonics on motor operation.

In order to solve the above technical problems, the technical solution of the present invention is to provide an asynchronous starting permanent magnet synchronous motor, which includes a stator winding. The stator winding is arranged in the slot of the stator core. It is characterized in that a rotor is provided in the stator core. There is a rotor two inside the rotor one, in which: there is a flat-bottomed squirrel cage groove on the outer circle of the rotor one, and there are cast aluminum or cast copper squirrel cage guide bars in the squirrel cage groove; the rotor two is composed of two sections of the rotor core. , the two sections of the rotor and the two cores are rotated by an angle between the two slots of the stator. There are magnetic steel slots on the second core of the rotor. There are magnets in the magnetic steel slots. A non-magnetic magnet is placed on the outer circle of the central axis of the two poles of the two cores of the rotor. The steel structural parts, the distance from the bottom of the squirrel cage groove to the inner hole of the rotor core of rotor one and the steel structural parts of rotor two jointly play the role of magnetic isolation.

Preferably, the steel structural component is a T-shaped steel structural component or a one-shaped steel structural component.

Preferably, the lower end of the T-shaped steel structural member has two triangular protrusions.

Preferably, the outer circumferential span of the steel structure member is the angle between the two squirrel cage slots of the rotor one plus the angle spanned by the bottom of the squirrel cage slot of the rotor one.

Preferably, a non-magnetic magnetic isolation sheet is provided between the two sections of the rotor cores.

The invention solves the production efficiency problem of the stator off-line and suppresses the influence of stator tooth harmonics on the operation of the motor. At the same time, the inter-pole magnetic leakage problem caused by the segmented torsion angle of rotor 2 is solved by adding steel structural parts.

Description of the drawings

Figure 1 is a schematic diagram of the final assembly structure of the motor. In the figure:

1-Stator core, 2-Stator winding, 3-Rotor one, 4-Rotor two, 11-Magnetic isolation sheet;

Figure 2(a) is a schematic structural diagram of rotor one;

Figure 2(b) is a cross-sectional view of the rotor core. In the figure:

5-rotor and an iron core, 6-squirrel cage;

Figure 3(a) and Figure 3(b) are schematic structural diagrams of the two magnets of the rotor being in a "V" shape;

Figure 3(c) is a partial enlarged view of part B in Figure 3(a);

Figure 3(d) is a partial enlarged view of part C in Figure 3(b). In the figure:

7-two iron cores of the rotor, 8-magnetic steel, 9-magnetic isolation groove, 10-non-magnetic T-shaped or one-shaped steel structural parts;

Figure 4(a) and Figure 4(b) are schematic structural diagrams of the rotor with two magnets in a "U" shape.

Detailed ways

In order to make the present invention more obvious and understandable, preferred embodiments are described in detail below along with the accompanying drawings.

The invention will be further described below with reference to specific examples, taking a 6-pole motor with a "V" shaped magnet arrangement on the rotor and a stator slot/rotor slot number of 54/48 as an example.

In order to ensure the smooth operation of the motor torque, the vibration generated by the motor is suppressed. In the present invention, when the stator core has a straight slot structure, the stator winding adopts concentric winding, and the rotor is divided into two parts: rotor one and rotor two, and the rotor two adopts the oblique pole method. The present invention mainly arranges the rotor magnets with "V"-shaped and "U"-shaped inclined poles.

As shown in Figure 1, a schematic diagram of the final assembly structure of the motor, the stator winding 2 is placed in the slot of the circular stator core 1. Inside the stator core 1 is the rotor 1 3, and inside the rotor 1 3 is the rotor 2 4. There is a flat-bottomed squirrel cage groove on the outer circle of the rotor 13, and there are guide bars of the cast aluminum or cast copper squirrel cage 6 in the squirrel cage groove. The second rotor 4 is composed of two sections of the second rotor core 7. The two sections of the second rotor core 7 are rotated by an angle between the two slots of the stator. The second rotor core 7 is provided with a magnetic steel slot, and the magnetic steel slot is provided with a magnetic steel 8. At "V There is a magnetic isolation groove 9 at the bottom of the "shape for magnetic isolation to reduce magnetic leakage. A non-magnetic T-shaped or I-shaped steel structure member 10 is placed at the outer circle of the central axis of the two poles of the second core 7 of the rotor. The non-magnetic steel structural member 10 forms a magnetic isolation structure together with the slot bottom part of the rotor 3 after the second core 7 of the rotor is twisted, thereby reducing the inter-pole magnetic leakage of the second core 7 of the rotor itself. The outer span of the steel structure member 10 is the angle between the two squirrel cage slots of the rotor 1 plus the angle spanned by the bottom of the squirrel cage slot of the rotor 1 3 . The distance from the bottom of the squirrel cage groove to the inner hole of the rotor core 5 and the non-magnetic T-shaped or I-shaped steel structure member 10 of the rotor 24 work together to play a magnetic isolation role. A non-magnetic magnetic isolation sheet 11 is placed in the middle of the two rotor cores 7 of the two rotor sections to reduce the mutual magnetic leakage between the two rotor cores 7 of the two rotor sections.

Claims (4)

1. An asynchronous starting permanent magnet synchronous motor, comprising a stator winding (2), wherein the stator winding (2) is arranged in a groove of a stator core (1), and is characterized in that a first rotor (3) is arranged in the stator core (1), and a second rotor (4) is arranged in the first rotor (3), wherein: the outer circle of the rotor I (3) is provided with a flat-bottomed squirrel cage groove, and the squirrel cage groove is internally provided with a guide bar of a squirrel cage (6) of cast aluminum or cast copper; the rotor II (4) is composed of two sections of rotor II iron cores (7), the two sections of rotor II iron cores (7) twist a distance angle between two slots of a stator, a magnetic steel slot is formed in the rotor II iron cores (7), magnetic steel (8) is arranged in the magnetic steel slot, a non-magnetic steel structural member (10) is arranged at the outer circle of the central axis of two poles of the rotor II iron cores (7), the distance from the bottom of the squirrel cage slot to the inner hole of a rotor I iron core (5) of the rotor I (3) and the steel structural member (10) of the rotor II (4) jointly play a magnetic isolation role, wherein the non-magnetic steel structural member (10) and the slot bottom part of the rotor I (3) jointly form a magnetic isolation structure after the rotor II iron cores (7) twist, so that interelectrode magnetic leakage of the rotor II iron cores (7) is reduced, and the outer circle span of the steel structural member (10) is the distance angle between two squirrel cage slots of the rotor I (3) plus the angle spanned by the squirrel cage slot bottom of the rotor I (3).

2. An asynchronous starting permanent magnet synchronous motor according to claim 1, characterized in that the steel structural member (10) is a T-shaped steel structural member or a steel structural member.

3. An asynchronous start permanent magnet synchronous motor according to claim 2 wherein the lower end of the T-section steel structure has two triangular projections.

4. An asynchronous starting permanent magnet synchronous motor according to claim 1, characterized in that a non-magnetically conductive magnetic barrier sheet (11) is provided between the two rotor cores (7).