CN101299560A - Flux switching type axial magnetic field permanent magnet brushless motor - Google Patents

Abstract

A magnetic flux switch type axial magnetic field permanent magnet brushless machine relates to a double air gap permanent magnet machine composed of two stators (1) and a rotor (2), wherein the stators (1) and a rotor (2) are arranged axially; the rotor (2) is clamped between two stators (1); the air gap with certain thickness is arranged between the stator (1) and the rotor (2); each stator (1) is composed of 12 U-shaped stator cores (3), 12 sector permanent magnets (4) and 12 coil2 (5); the U-shaped stator cores (3) and the sector permanent magnets (4) are put alternately to constitute the disc; the U-shaped stator core (3) and the permanent magnet (4) are respectively corresponding on the two stators (1), but the magnetizing directions of the two corresponding permanent magnets are opposite. The simple structure advances the operation reliability and the dynamic performance of the motor, meanwhile the axial size is smaller, which is suitable for the place requiring the thin mount, such as the robot, the computer peripherals, the electric automobiles and the wind electric power generation and the like.

Description

Flux Switching Axial Field Permanent Magnet Brushless Motor

technical field

The invention relates to a magnetic flux switching type axial magnetic field permanent magnet brushless motor, which is an improvement to the traditional axial magnetic field permanent magnet brushless motor and belongs to the technical field of permanent magnet motors.

Background technique

The traditional axial magnetic field permanent magnet brushless motor adopts a slotless structure with a small magnetic load, while a slotted structure has a higher power density but is difficult to manufacture and requires special equipment. Regardless of whether it is a single air gap or double air gap axial field permanent magnet brushless motor, the rotor is composed of high performance permanent magnet materials bonded to solid steel or silicon steel sheets. Since this kind of motor places permanent magnets on the rotor, in order to overcome the centrifugal force during high-speed operation, it is necessary to take special auxiliary measures for the rotor, such as installing fixtures made of stainless steel or non-metallic fiber materials, etc., which undoubtedly increases the speed of the rotor. The complexity of the structure also increases the manufacturing cost of the motor. At the same time, the permanent magnet is located in the rotor, the cooling condition is poor, and heat dissipation is difficult, and the high temperature rise may eventually lead to irreversible demagnetization of the permanent magnet, limit the output of the motor, reduce the power density of the motor, etc., restricting the further improvement of the performance of the motor .

The flux-switching permanent magnet motor proposed by the French scholar E.Hoang, the motor places the permanent magnet on the stator, so that the structure of the rotor is simple, and there is neither winding nor permanent magnet on the rotor, which avoids the above problems, but This kind of motor is a radial field motor, which is not suitable for occasions that strictly require thin installation. The single air gap structure makes the power density of the motor low.

Contents of the invention

Technical problem: In view of the problems existing in the traditional axial magnetic field permanent magnet brushless motor and the flux switching permanent magnet motor, in order to improve the performance of the axial magnetic field permanent magnet motor, the present invention proposes a flux switching type axial magnetic permanent magnet motor Magnetic brushless motor.

Technical solution: The flux-switching axial field permanent magnet motor proposed by the present invention is a double-air-gap permanent magnet motor composed of two stators and a rotor. The stator and the rotor are installed coaxially, and the rotor is sandwiched between the two stators. , there is an air gap between the rotor and the stator. The motor is obtained by multiplying the "basic motor" composed of 6 U-shaped stator cores and 6 permanent magnets with a stator unit/5 rotor poles. If the basic motor is expanded by integer multiples, 6a/ 5a structure of the motor, where a is a positive integer.

The structures of the two stators are exactly the same, and they are symmetrical about the rotor; the typical structure is that each stator includes 12 U-shaped stator cores, 12 sector-shaped permanent magnets and concentrated windings composed of 12 coils, U-shaped stator cores and sector-shaped The permanent magnets are alternately placed to form a disc, and the two symmetrical permanent magnets of the two stators have opposite excitation directions; 12 coils are divided into three phases, and every four coils are connected in series to form a phase winding, and each coil is wound on two U-shaped stator irons. On the teeth of the core, permanent magnets are embedded in the middle, and the permanent magnets are alternately magnetized along the circumferential direction. The rotor has a total of 10 teeth, called 10 rotor poles, which are evenly arranged on the outer circumference of the non-magnetic ring of the rotor. The teeth of the U-shaped stator core and the rotor poles are all parallel teeth, or sector teeth.

Beneficial effects: the magnetic flux switching axial magnetic field permanent magnet motor proposed by the present invention combines the advantages of the traditional axial magnetic field permanent magnet brushless motor and the magnetic flux switching permanent magnet motor. High power density, simple rotor structure and short axial size overcome a series of problems caused by permanent magnets placed on the rotor. As mentioned in the background art, the reliability of the stable operation of the motor is improved. The stator adopts a "U"-shaped unit core, which is convenient to manufacture compared with the traditional axial magnetic field permanent magnet motor; due to the simple structure of the rotor, there is neither permanent magnet nor winding, the moment of inertia is small, and it has excellent fast response performance, which improves the motor's performance. Dynamic performance; at the same time, the axial dimension is small, which is very suitable for occasions that strictly require thin installation.

Description of drawings

Fig. 1 is a schematic diagram of the axially expanded structure of the flux switching type axial field permanent magnet motor,

Fig. 2 is a plane expanded view of the flux switching type axial field permanent magnet motor,

The above figure has: stator 1, rotor 2, rotor pole 17, non-magnetic ring 18, stator core 3, permanent magnet 4, concentrated winding 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16.

Detailed ways

The motor consists of 6 U-shaped stator cores 3 and 6 permanent magnets 4. The stator 1 and 5 rotor poles 17 are combined into a basic motor with a 6/5 structure. The stator 1 and rotor poles 17 of the basic motor are integer multiples. By extension, a motor with a structure of 6a/5a can be obtained, where a is a positive integer.

As shown in Figure 1, the flux-switching axial field permanent magnet brushless motor is a double air gap permanent magnet motor composed of two stators 1 and a rotor 2. The stator 1 and the rotor 2 are coaxially installed, and the rotor 2 is sandwiched Between the two stators 1, there is an air gap of a certain thickness between the rotor 2 and the stator 1. The structures of the two stators 1 are exactly the same, and they are symmetrical about the rotor 2; each stator 1 is composed of 12 U-shaped stator cores 3, 12 sector-shaped permanent magnets 4 and 12 concentrated windings 5, and the U-shaped stator core 3 and sector-shaped permanent magnets 4 are alternately placed to form a disk, and the U-shaped stator cores 3 and permanent magnets 4 in the two stators 1 are respectively corresponding, but the excitation directions of the corresponding two permanent magnets 4 are opposite; 12 The concentrated coil 5 is divided into three phases, and every four coils are connected in series to form a phase winding. Each coil is wound on the teeth of two U-shaped stator cores 3, and a permanent magnet 4 is embedded in the middle, and the permanent magnet 4 is alternately magnetized along the circumferential direction. . The rotor 2 has 10 teeth in total, which are called 10 rotor poles 17 , which are evenly arranged on the outer circumference of the non-conductive ring 18 of the rotor 2 .

Each coil straddles the teeth of the two U-shaped stator cores 3, and the permanent magnets 4 are embedded in the middle of the teeth of the two U-shaped stator cores 3, and the permanent magnets 4 are alternately magnetized along the circumferential direction. The U-shaped stator core 3 is punched from a silicon steel sheet. The rotor 2 has a simple structure, neither permanent magnets nor coils, and the rotor has 10 teeth in total, called 10 poles. The rotor pole 2 is also formed by stamping silicon steel sheets with high magnetic permeability.

As shown in Figure 2, a certain pole of the rotor is facing the stator teeth. Let the current direction of the left conductor of the coil on the upper stator facing the rotor pole be perpendicular to the inside of the paper, and the current direction of the other conductor (right conductor) of this coil is Perpendicular to the outside of the paper, the direction of current in the left and right conductors of the coil of the lower stator opposite to this coil is opposite, that is, the current direction of the left conductor is perpendicular to the inside of the paper, and the current direction of the right conductor is perpendicular to the outside of the paper. According to Ampere's law, the current-carrying conductors of the two stators are subjected to the horizontal ampere force to the left. Because the coil is fixed on the stator, it will not rotate. According to the relationship between the action force and the reaction force, the rotor will be subjected to a horizontal rightward ampere force, so the rotor will move to the right, thus realizing the electric operation of the motor.

The permanent magnet machine of the invention can also be operated as a generator. When the external prime mover drives the rotor to rotate continuously, the change of the permanent magnet flux linkage in the armature winding will generate a sinusoidal three-phase induced electromotive force in the winding, which is connected with the load to output AC current, which realizes the power generation of the motor run.

Claims (5)

1. A magnetic flux switching type axial field permanent magnet brushless motor is characterized in that the motor is a double air gap permanent magnet motor consisting of two stators (1) and a rotor (2), and the stator (1) and rotor (2) Coaxial installation, the rotor (2) is sandwiched between two stators (1), and an air gap is left between the rotor (2) and the stator (1). 2. The magnetic flux switching type axial field permanent magnet brushless motor according to claim 1, characterized in that the motor is composed of 6 U-shaped stator cores (3) and 6 permanent magnets (4). 1) Combining with 5 rotor poles (17) to form a basic motor with a 6/5 structure, the stator (1) and rotor poles (17) of the basic motor are expanded by integer multiples to obtain a motor with a 6a/5a structure, where a is a positive integer. 3. The magnetic flux switching type axial field permanent magnet brushless motor according to claim 1, characterized in that the structures of the two stators (1) are exactly the same, and are symmetrical about the rotor (2); each stator (1) Concentrated winding (5) consisting of 12 U-shaped stator cores (3), 12 sector-shaped permanent magnets (4) and 12 coils, U-shaped stator cores (3) and sector-shaped permanent magnets (4) are alternately placed to form a Disc, two stators (1) and two symmetrical permanent magnets (4) have opposite excitation directions; 12 coils are divided into three phases, and every four coils are connected in series to form a phase winding, and each coil is wound on two U-shaped stators On the teeth of the iron core (3), permanent magnets (4) are embedded in the middle, and the permanent magnets (4) are alternately magnetized along the circumferential direction. 4. The magnetic flux switching type axial field permanent magnet brushless motor according to claim 1, characterized in that the rotor (2) has 10 teeth in total, called 10 rotor poles (17), which are evenly arranged on the rotor (2 ) on the outer circumference of the non-magnetic conduction ring (18). 5. The magnetic flux switching axial field permanent magnet brushless motor according to claim 1, characterized in that the teeth of the U-shaped stator core (3) and the rotor poles (17) are all parallel teeth, or sector teeth .

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