Interpolated low power consumption hybrid excitation magnetic bearing

Abstract

This invention discloses an intercalated low-power hybrid excitation magnetic bearing, comprising a stator and a rotor core. The stator includes a stator core, permanent magnets, and excitation windings. The stator core has large and small teeth distributed circumferentially. Axially slotted sections are formed in the middle of the large and small teeth, embedding radially magnetized permanent magnets. The magnetization directions of the permanent magnets in adjacent large and small teeth are opposite. Each core tooth is equipped with an excitation coil, with adjacent excitation coils having opposite currents. All excitation coils are connected in series to form a unified excitation circuit. The rotor core is coaxially mounted with the stator, and a uniform air gap is maintained between the stator and rotor core. This invention has the advantages of reduced energy consumption and temperature rise, reduced size and cost, improved control performance, protection of permanent magnets, and high structural strength.

Description

Technical Field

[0001] This invention belongs to the field of magnetic levitation bearing technology, and particularly relates to an intercalation-type low-power hybrid excitation magnetic bearing. Background Technology

[0002] Magnetic bearings enable non-contact support between the motor rotor and stator, offering advantages such as frictionless operation, wear-free operation, no lubrication required, and long service life. They are widely used in high-speed motors, flywheel energy storage, aerospace, and other fields.

[0003] Traditional electrically excited magnetic bearings rely entirely on winding current to generate bias and control magnetic fields, requiring a continuous supply of large currents. This results in drawbacks such as high energy consumption, severe heat generation, low efficiency, and difficulty in heat dissipation.

[0004] Existing permanent magnet bias bearings typically arrange the permanent magnets axially. This results in a large quantity of permanent magnets, high cost, and an increased winding end length, leading to a large axial dimension, bulky overall size, and high difficulty in manufacturing and assembly. Furthermore, the traditional armature magnetic circuit exhibits high magnetic reluctance, resulting in relatively high control current losses. Additionally, the permanent magnets are susceptible to demagnetization due to the armature demagnetizing field, reducing bearing operational stability and service life. Summary of the Invention

[0005] This invention aims to solve the technical problems of high energy consumption and high temperature rise of traditional electrically excited magnetic bearings, as well as the large size, high cost, large control loss, and easy demagnetization of permanent magnet bias magnetic bearings. It provides a hybrid excitation magnetic bearing with low energy consumption, small size, high efficiency, and high stability.

[0006] The present invention discloses an intercalated low-power hybrid excitation magnetic bearing, comprising a stator and a rotor core. The stator includes a stator core, permanent magnets, and excitation windings. The stator core has large and small teeth distributed circumferentially. The large and small teeth have axial slots in their middle portions and radially magnetized permanent magnets are embedded therein. The permanent magnets in adjacent large and small teeth are magnetized in opposite directions. Each core tooth is provided with an excitation coil. The currents of adjacent excitation coils are opposite, and all excitation coils are connected in series to form a unified excitation circuit. The rotor core is coaxially mounted with the stator, and a uniform air gap is maintained between the stator and the rotor core.

[0007] Furthermore, the stator core is made of silicon steel sheets stacked axially, and the rotor core is also made of silicon steel sheets stacked axially.

[0008] Furthermore, the large and small teeth of the stator core are evenly distributed along the circumference, with the small teeth distributed on both sides of the large teeth and arranged alternately.

[0009] Furthermore, modulation tooth ribs are provided next to the permanent magnets of both the large and small teeth, with the large teeth corresponding to the large tooth ribs and the small teeth corresponding to the small tooth ribs, forming an integrated modulation tooth structure.

[0010] Furthermore, the excitation coil includes a large-tooth excitation coil and a small-tooth excitation coil, with the large-tooth excitation coil wound around the large teeth and the small-tooth excitation coil wound around the small teeth.

[0011] Furthermore, the permanent magnet establishes a stable bias magnetic field in the air gap, and the magnetic force generated on the rotor core is circumferentially symmetrical, with a resultant force of zero. The excitation winding is supplied with control current to generate a controllable and adjustable magnetic field, which is superimposed on the bias magnetic field to adjust the magnitude and distribution of the air gap magnetic field in real time, thereby precisely controlling the electromagnetic resultant force on the rotor core and realizing stable suspension and high-precision radial support of the rotor core.

[0012] The beneficial technical effects of this invention are as follows:

[0013] 1. Reduced energy consumption and temperature rise: Permanent magnets provide the main bias magnetic field, and the windings only require a small current to achieve control, which significantly reduces copper loss and iron loss, resulting in lower temperature rise and higher efficiency.

[0014] 2. Reduced size and cost: The permanent magnet is radially embedded inside the iron core teeth, eliminating the need for axial arrangement, reducing the amount of permanent magnet used, shortening the winding ends, and reducing the overall size of the bearing.

[0015] 3. Improve control performance: Modulation of the ribs optimizes the armature magnetic circuit, reduces magnetic resistance, decreases control current, and improves magnetic field response speed and control accuracy.

[0016] 4. Protect permanent magnets: The modulated tooth ribs provide a bypass magnetic flux circuit for the permanent magnets, weakening the armature demagnetization effect, preventing permanent magnet demagnetization, and improving reliability and lifespan.

[0017] 5. High structural strength: The modulated tooth ribs connect each core tooth, enhancing the overall mechanical strength of the stator and preventing the core teeth from breaking under stress. Attached Figure Description

[0018] Figure 1 This is a cross-sectional view of the intercalation-type low-power hybrid excitation magnetic bearing structure of the present invention.

[0019] Figure 2 This invention relates to the stator core modulation tooth rib structure of the intercalated low-power hybrid excitation magnetic bearing.

[0020] Figure 3 This is an exploded view of the intercalation-type low-power hybrid excitation magnetic bearing structure of the present invention.

[0021] In the diagram: 1-Stator core, 11-Large tooth, 12-Small tooth, 2-Permanent magnet, 3-Excitation winding, 31-Large tooth excitation coil, 32-Small tooth excitation coil, 4-Rotor core, 13-Modulation tooth rib, 111-Large tooth rib, 121-Small tooth rib, 5-Air gap, 51-Large tooth air gap, 52-Small tooth air gap.

[0022] Figure 4The magnetic field distribution of a magnetic bearing for individually excitation of permanent magnets.

[0023] Figure 5 The magnetic field distribution of the permanent magnet electromagnetic hybrid excitation magnetic bearing. Detailed Implementation

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0025] An intercalation-type low-power hybrid excitation magnetic bearing of the present invention, such as Figure 3 As shown, it includes a stator and a rotor core 4. The stator includes a stator core 1, a permanent magnet 2, and an excitation winding 3. Figure 1 As shown, the stator core 1 has large teeth 11 and small teeth 12 distributed along the circumference; the large teeth 11 and small teeth 12 have axial slots in the middle (the slot width is smaller than the core tooth width) and radially magnetized permanent magnets 2 are embedded in them, and the magnetization direction of the permanent magnets 2 in adjacent large teeth 11 and small teeth 12 is opposite; each core tooth is provided with an excitation coil 3, the current of adjacent excitation coils 3 is opposite, and all excitation coils 3 are connected in series to form a unified excitation circuit; the rotor core 4 is installed coaxially with the stator, and a uniform air gap 5 is maintained between the stator and the rotor core 4.

[0026] Furthermore, the stator core 1 is made of silicon steel sheets stacked axially, and the rotor core 4 is made of silicon steel sheets stacked axially, which effectively reduces eddy current loss and hysteresis loss.

[0027] Furthermore, the large teeth 11 and small teeth 12 of the stator core 1 are evenly distributed along the circumference, with the small teeth 12 distributed on both sides of the large teeth 11 and arranged alternately.

[0028] Furthermore, such as Figure 2 As shown, modulation tooth ribs 13 are provided next to the permanent magnets 2 of both large tooth 11 and small tooth 12. Large tooth 11 corresponds to large tooth rib 111, and small tooth 12 corresponds to small tooth rib 121, forming an integrated modulation tooth structure.

[0029] Furthermore, such as Figure 1 As shown, the excitation coil 3 includes a large-tooth excitation coil 31 and a small-tooth excitation coil 32. The large-tooth excitation coil 31 is wound with a large tooth 11, and the small-tooth excitation coil 32 is wound with a small tooth 12.

[0030] Furthermore, the permanent magnet 2 establishes a stable bias magnetic field in the air gap 5, and the magnetic force generated on the rotor core 4 is circumferentially symmetrical, with a resultant force of zero; the excitation winding 3 is supplied with control current to generate a controllable and adjustable magnetic field, which is superimposed on the bias magnetic field to adjust the magnitude and distribution of the magnetic field in the air gap 5 in real time, thereby precisely controlling the electromagnetic resultant force on the rotor core 4 and realizing stable suspension and high-precision radial support of the rotor core 4.

[0031] Furthermore, such as Figure 4As shown, no current flows through the excitation coil 3. When the permanent magnet 2 is energized alone, the magnetic lines of force in the magnetic bearing are evenly and symmetrically distributed along the circumference of the rotor core 4, and the resultant electromagnetic force on the rotor core 4 is zero.

[0032] Furthermore, such as Figure 5 As shown, current flows through the excitation coil 3. The magnetic field in the air gap 5 is the superposition of the magnetic field generated by the excitation coil 3 and the magnetic field generated by the permanent magnet 2. The magnetic fields are enhanced at the upper and right sides of the rotor core 4, and weakened by cancellation at the lower and left sides of the rotor core 4. The rotor core 4 is subjected to a resultant force upward and to the right. The magnitude and direction of the force on the rotor core 4 can be changed by adjusting the current.

Claims

1. An intercalation-type low-power hybrid excitation magnetic bearing, characterized in that, The stator includes a stator and a rotor core (4). The stator includes a stator core (1), a permanent magnet (2), and an excitation winding (3). The stator core (1) has large teeth (11) and small teeth (12) distributed along the circumference. The large teeth (11) and small teeth (12) have axial slots in the middle and radially magnetized permanent magnets (2) are embedded. The permanent magnets (2) in adjacent large teeth (11) and small teeth (12) have opposite magnetization directions. Each core tooth is provided with an excitation coil (3). The currents of adjacent excitation coils (3) are opposite. All excitation coils (3) are connected in series to form a unified excitation circuit. The rotor core (4) is installed coaxially with the stator. A uniform air gap (5) is maintained between the stator and the rotor core (4).

2. The intercalation-type low-power hybrid excitation magnetic bearing according to claim 1, characterized in that, The stator core (1) is made of silicon steel sheets stacked axially, and the rotor core (4) is made of silicon steel sheets stacked axially.

3. The intercalation-type low-power hybrid excitation magnetic bearing according to claim 1, characterized in that, The large teeth (11) and small teeth (12) of the stator core (1) are evenly distributed along the circumference, with the small teeth (12) distributed on both sides of the large teeth (11) and arranged alternately.

4. The intercalation-type low-power hybrid excitation magnetic bearing according to claim 1, characterized in that, Modulation ribs (13) are provided next to the permanent magnets (2) of both the large tooth (11) and the small tooth (12), with the large tooth (11) corresponding to the large tooth rib (111) and the small tooth (12) corresponding to the small tooth rib (121), forming an integrated modulation tooth structure.

5. The intercalation-type low-power hybrid excitation magnetic bearing according to claim 1, characterized in that, The excitation coil (3) includes a large tooth excitation coil (31) and a small tooth excitation coil (32). The large tooth excitation coil (31) is wound around the large tooth (11), and the small tooth excitation coil (32) is wound around the small tooth (12).

6. The intercalation-type low-power hybrid excitation magnetic bearing according to claim 1, characterized in that, The permanent magnet (2) establishes a stable bias magnetic field in the air gap (5), and the magnetic force generated on the rotor core (4) is circumferentially symmetrical, with a resultant force of zero. The excitation winding (3) is supplied with control current to generate a controllable and adjustable magnetic field, which is superimposed on the bias magnetic field to adjust the magnitude and distribution of the magnetic field in the air gap (5) in real time, thereby accurately controlling the electromagnetic resultant force on the rotor core (4) and realizing stable suspension and high-precision radial support of the rotor core (4).

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